Figure 1. Production of artemisinic acid or β-farnesene by engineered yeast. The sesquiterpene alkenes β-farnesene and amorphadiene are both derived from FPP (farnesyl diphosphate) by the action of specific enzymes introduced from plants: amorphadiene synthase (ADS) generates amorphadiene and β-farnesene synthase (FS) generates β-farnesene. Production strains express either ADS or FS, not both. Oxidation of amorphadiene to artemisinic acid is accomplished by the action of five plant enzymes expressed in the engineered yeast.17 Conversion of purified artemisinic acid to artemisinin is accomplished by in vitro organic chemistry. Isoprenoid production strains make little ethanol.

The antimalarial drug artemisinin and the specialty chemical β-farnesene are examples of natural product isoprenoids that can help solve global challenges, but whose usage has previously been limited by supply and cost impediments. This review describes the path to commercial production of these compounds utilizing fermentation of engineered yeast. Development of commercially viable yeast strains was a substantial challenge that was addressed by creation and implementation of an industrial synthetic biology pipeline. Using the engineered strains, production of β-farnesene from Brazilian sugarcane offers several environmental advantages. Among the many commercial applications of β-farnesene, its use as a feedstock for making biodegradable lubricants is highlighted. This example, along with others, highlight a powerful new suite of technologies that will become increasingly important for production of chemicals, spanning from pharmaceuticals through commodity chemicals.

Figure 2. Sanofi industrial semi-synthesis of artemisinin. The process starts with a moderate pressure catalytic diastereoselective hydrogenation of artemisinic acid to produce a high (95:5) ratio of the desired (R)-isomer. To avoid formation of a lactone byproduct, dihydro-epi-deoxyarteannuin B, during the photooxidation, the carboxylic acid is protected as a mixed anhydride. The final step combines formation of the intermediate hydroperoxide via photoxidation using a Hg vapor lamp and commercially available tetraphenylporphyin (TPP) as sensitizer with a Hock cleavage and rearrangement catalyzed by trifluoroacetic acid to give, after workup, the best yield reported to date of pure isolated artemisinin (55%).

Synthetic Biology and the Development of Commercial β-Farnesene Production Strains Semi-synthetic artemisinin is a pharmaceutical with a price point comparable to plant-derived artemisinin,20 namely above $150 per kg. β-Farnesene, however, is a specialty chemical with multiple uses (more details below); most specialty and commodity chemicals have significantly lower price points, often below $10 per kg. For these product categories, it is of paramount importance that fermentative production be as efficient as possible, with high yields (namely, grams of product made per gram of feed substrate), productivities (grams of product/liter of culture/hour) and concentration (also known as titer; grams of product per liter of culture). Developing yeast strains capable of the yield, productivity and titer required for chemical production requires extensive development, and has been enabled over the last decade by the new discipline of synthetic biology. Synthetic biology seeks to extend approaches and concepts from engineering and computation to redesign biology for a chosen function;21recent advances in the application of design automation, i.e., the use of software, hardware and robotics22 have enabled the creation and screening of hundreds of thousands of strain variants (created by both design and random mutagenesis) for the properties required for commercial production of β-farnesene. Notable enabling technologies developed for routine usage include rapid and reliable assembly of large (i.e., multiple kilobase) deoxyribonucleic acid (DNA) constructs;23-25 high throughput, cost effective, verification of structural DNA assemblies by both initial restriction digest26 and by low-cost DNA sequencing;27 and whole genome sequencing of yeast strains.28 In addition, there is a need to effectively identify the best new strains (akin to panning for gold!) through high throughput, rapid, and accurate methods to screen thousands of strains. Further, the results of small-scale (< 1 milliliter) tests must correspond to the results of large-scale (> 50,000 liter) production. Development and implementation of these technologies required considerable investment by Amyris. The outcome is a robust pipeline for efficient, cost-effective strain generation allied with screening for the properties required for commercial production of β-farnesene by fermentation (i.e., at a price point required for its use as a specialty chemical).

As the world’s population and economies grow, the demand for a wide variety of specialty, commodity, and pharmaceutical chemicals will outpace the supply available from current sources. There is an urgent need to develop alternative, sustainable sources of many existing chemicals and to develop abundant sources of currently scarce chemicals with novel beneficial properties. Synthetic biology and industrial fermentation, combined with synthetic chemistry, will be an increasingly important source of chemicals in the decades ahead; artemisinin and β-farnesene provide good examples of this relatively new approach to chemical production. Brazil’s plentiful sugar cane feedstock and fermentation expertise make it an excellent location for this type of manufacturing, which can expand and diversify the nation’s industrial base and international importance.

J. Braz. Chem. Soc. 2016, 27(8), 1339-1345

Developing Commercial Production of Semi-Synthetic Artemisinin, and of β-Farnesene, an Isoprenoid Produced by Fermentation of Brazilian Sugar

Kirsten R. Benjamin; Iris R. Silva; João P. Cherubim; Derek McPhee; Chris J. Paddon

How to cite this article

Genes encoding the biosynthetic pathway for production of a valuable product (e.g., farnesene) in a native organism are expressed in a heterologous microbial host (e.g., yeast). The engineered yeast produces farnesene by commercial fermentation. Copyright © 2016 Amyris, inc. All rights reserved.

http://dx.doi.org/10.5935/0103-5053.20160119

http://jbcs.sbq.org.br/imagebank/pdf/v27n8a04.pdf

Benjamin KR, Silva IR, Cherubim JP, Mcphee D, Paddon CJ. Developing Commercial Production of Semi-Synthetic Artemisinin, and of β-Farnesene, an Isoprenoid Produced by Fermentation of Brazilian Sugar. J. Braz. Chem. Soc. 2016;27(8):1339-1345

Kirsten R. Benjamin,a Iris R. Silva,b João P. Cherubim,c Derek McPheea and Chris J. Paddon*,a a Amyris, Inc., 5885 Hollis Street, Suite 100, CA 94608 Emeryville, USA b Amyris Brasil Ltda, Rua John Dalton 301-Bloco B-Edificio 3, Condominio Techno Plaza, 13069-330 Campinas-SP, Brazil c Amyris Brasil Ltda, Rodovia Brotas/Torrinha-km 7.5, 17380-000 Brotas-SP, Brazil

*e-mail: paddon@amyris.com

Chris Paddon, PhD

Dr. Paddon has a PhD in Biochemistry from Imperial College, London, but now considers himself a synthetic biologist. After postdoctoral work at the National Institutes of Health in Bethesda, MD, he worked in the pharmaceutical industry (GlaxoSmithKline), and then for two Bay Area biopharmaceutical companies (Affymax and Xenoport) before joining Amyris, Inc. in 2005 as its sixth employee and first scientist. He was project leader for the semi-synthetic artemisinin project at Amyris, Inc. and has subsequently led a number of other projects and programs there.

Chris Paddon is a Principal Scientist at Amyris, Inc. in Emeryville, CA. He was project leader for the Semi-Synthetic Artemisinin project, and subsequently led a number of projects at Amyris using synthetic biology for the production of natural products. He received his Bachelor’s degree in Microbiology from The University of Surrey (UK), and doctorate in Biochemistry from Imperial College (London, UK). Following postdoctoral work at The National Institutes for Health (Bethesda, MD) he joined the pharmaceutical industry, working for GSK (London, UK). He subsequently worked for Affymax (Palo Alto, CA) and Xenoport (Santa Clara, CA) before joining Amyris.

//////////// Commercial Production, Semi-Synthetic , Artemisinin,  farnesene, fermentation, natural product, lubricant

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DESCRIPTION

//////////

Nacubactam

RG-6080,  FPI-1459,  OP-0595, WK ?, WK-?, WK?

(2S,5R)-N-(2-amino ethoxy)-6-(sulfooxy)-7-oxo-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

Beta lactamase inhibitor

Roche, under license from Meiji Seika Pharma and Fedora Pharmaceuticals is developing nacubactam hydrate

Meiji Seika Pharma Co., Ltd., Ｍｅｉｊｉ Ｓｅｉｋａファルマ株式会社

A diazabicyclooctane beta-lactamase inhibitor, for treating bacterial infection. In July 2016, nacubactam was reported to be in phase 1 clinical development

PATENTS , IN2015MU287, WO2016116878, WO 2016120752, INDICATE INTEREST FROM WOCKHARDT

• Originator Fedora Pharmaceuticals
• Developer Meiji Seika Pharma
• Class Antibacterials; Azabicyclo compounds
• Mechanism of Action Beta lactamase inhibitors

• Phase I Bacterial infections

Most Recent Events

• 13 Jan 2015  OP 0595 licensed to Roche worldwide, except Japan ,
• 30 Nov 2014 Meiji Seika Pharma completes a phase I trial in Healthy volunteers in Australia (NCT02134834)
• 01 May 2014 Phase-I clinical trials in Bacterial infections (in volunteers) in Australia (IV)

SYNTHESIS

PATENT

IN2015MU287

PATENT

WO2013180197

Example 59
(2S, 5R) -N- (2- aminoethoxy) -7-oxo-6- (sulfooxy) 1,6-diazabicyclo [3.2.1] octane-2-carboxamide (II-059)

Step 1
tert- butyl {2 – [({[(2S, 5R) -6- Benzyloxy-7-oxo-1,6-diazabicyclo [3.2.1] oct-2-yl] carbonyl} amino) oxy] ethyl } carbamate

Acid of Example 9 or 16 (6b, 1.34g, 4.87mmol) in methylene chloride (35mL) solution of triethylamine (2.71mL), N- ethyl -N ‘- (3- dimethylaminopropyl) carbodiimide hydrochloride (1.41g), 1- hydroxybenzotriazole monohydrate (1.15g), were added tert- butyl of Reference Example 9, wherein 2- (amino-oxy) ethyl carbamate (1.12g), room temperature It was stirred overnight Te.Water was added to the reaction solution to a residue obtained by concentration under reduced pressure, and extracted with ethyl acetate. The resulting organic layer with 0.1M hydrochloric acid, saturated aqueous sodium bicarbonate solution, washed with saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, filtered and concentrated.The resulting residue was purified by silica gel column and purified by chromatography (hexane / ethyl acetate = 8 / 2-0 / 10) to give the title compound 1.77g (84% yield).
[Α] _D ²⁰ -0.08 ° (c 0.29, CHCl _3); ¹ H NMR (400 MHz, CDCl _3), δ: 1.44 (s, 9H), 1.56-1.70 (m, 1H), 1.90-2.09 (m , 2H), 2.25-2.38 (m, 1H), 2.76 (d, J = 11.6 Hz, 1H), 3.03 (br d, J = 11.6 Hz, 1H), 3.24-3.47 (m, 3H), 3.84-4.01 (m, 3H), 4.90 (d, J = 11.6 Hz, 1H), 5.05 (d, J = 11.6 Hz, 1H), 5.44 (br s, 1H), 7.34-7.48 (m, 5H), 9.37 (br s, 1H); MS m / z 435 [M ⁺ H] +; enantiomeric excess of 99.9% or higher ee (CHIRALPAK AD-H, 4.6x150mm, hexane / ethanol = 2/1, UV210nm, flow rate 1mL / min, retention time 4.95min (2R, 5S), 6.70min (2S, 5R).

Step 2
tert- butyl {2 – [({[(2S, 5R) -1,6- -6- hydroxy-7-oxo-diazabicyclo [3.2.1] oct-2-yl] carbonyl} amino) oxy] ethyl} carbamate

Compound of the above Step 1 (3.91g, 9.01mmol) in methanol (80mL), 10% palladium on carbon catalyst (50% water, 803mg) was added, under hydrogen atmosphere and stirred for 45 minutes. The reaction mixture was filtered through Celite, then concentrated under reduced pressure, to give 3.11g of the title compound (quantitative).
¹ H NMR (400 MHz, CD ₃ OD), ^δ: 1.44 (s, 9H), 1.73-1.83 (m, 1H), 1.86-1.99 (m, 1H), 2.01-2.12 (m, 1H), 2.22 ( br dd, J = 15.0, 7.0 Hz, 1H), 3.03 (d, J = 12.0 Hz, 1H), 3.12 (br d, J = 12.0 Hz, 1H), 3.25-3.35 (m, 2H), 3.68-3.71 (m, 1H), 3.82-3.91 (m, 3H); MS m / z 345 [M ⁺ H] +.

Step 3
(2S, 5R) -N- (2- aminoethoxy) -7-oxo-6- (sulfooxy) 1,6-diazabicyclo [3.2.1] octane-2-carboxamide The above step 2 compound (3. 09g, in methylene chloride (80mL) solution of 8.97mmol), 2,6- lutidine (3.20mL), sulfur trioxide – was added pyridine complex (3.58g), and stirred at room temperature overnight. The reaction mixture was poured into half-saturated aqueous sodium bicarbonate solution, and washed the aqueous layer with chloroform, and tetrabutylammonium hydrogen sulfate (3.47g) and chloroform (30mL) was added to the aqueous layer and stirred for 10 minutes. After extracting the aqueous layer with chloroform, drying the resulting organic layer over anhydrous sodium sulfate, filtered, concentrated under reduced pressure tetrabutylammonium tert- butyl {2 – [({[(2S, 5R) -7- oxo – 6- (sulfooxy) 1,6-diazabicyclo [3.2.1] oct-2-yl] carbonyl} amino) oxy] ethyl} carbamate was obtained 5.46g (91% yield).
¹ H NMR (400 MHz, CDCl _3), ^δ: 1.01 (t, J = 7.4 Hz, 12H), 1.37-1.54 (m, 8H), 1.45 (s, 9H), 1.57-1.80 (m, 9H), 1.85-1.98 (m, 1H), 2.14-2.24 (m, 1H), 2.30-2.39 (m, 1H), 2.83 (d, J = 11.6 Hz, 1H), 3.20-3.50 (m, 11H), 3.85- 3.99 (m, 3H), 4.33-4.38 (m, 1H), 5.51 (br s, 1H), 9.44 (br s, 1H); MS m / z 425 [M-Bu ₄ N ⁺ 2H] +.

The tetrabutyl ammonium salt (5.20g, 7.82mmol) in methylene chloride (25mL) solution of under ice-cooling trifluoroacetic acid (25mL), and the mixture was stirred for 1 hour at 0 ℃. The reaction mixture was concentrated under reduced pressure, washed resulting residue with diethyl ether, at aqueous sodium bicarbonate was adjusted to pH7, it performs an octadecyl silica gel column chromatography (water), after freeze-drying, 1.44g of the title compound The obtained (57% yield).
[Α] _D ²⁴ -63.5 ° (c 0.83, H ₂ O); ¹ H NMR (400 MHz, _{D 2} O), δ: 1.66-1.76 (m, 1H), 1.76-1.88 (m, 1H), 1.91 -2.00 (m, 1H), 2.00-2.08 (m, 1H), 3.02 (d, J = 12.0 Hz, 1H), 3.15 (t, J = 5.0 Hz, 2H), 3.18 (br d, J = 12.0 Hz , 1H), 3.95 (dd, J = 7.8, 2.2 Hz, 1H), 4.04 (t, J = 5.0 Hz, 2H), 4.07 (dd, J = 6.4, 3.2 Hz, 1H); MS m / z 325 [ M ⁺ H] +.

PATENT

WO2016116878

ANTIBACTERIAL COMPOSITIONS OF A BETA-LACTAMASE INHIBITOR WITH A CEPHALOSPORINAbstract:

PATENT

WO 2016120752, WOCKHARDT, NEW PATENT, Nacubactam

Formula (I), chemically known as (25, 5i?)-N-(2-aminoethoxy)-6-(sulfooxy)-7-oxo-l ,6-diazabicyclo[3.2.1 ]octane-2-carboxamide has antibacterial properties and is disclosed in PCT International Patent Application No. PCT/IB2013/053092, PCT/JP2013/064971 and PCT/IB2012/002675. The present invention discloses a process for preparation of a compound of Formula (I).

Formula (I)

(VII) (VIII) (IX)

Scheme 2

Example 1

Synthesis of fert-butyl-r2-(aminooxy) ethyllcarbamate (III)

Preparation of fert-butyl-2-hydroxy ethylcarbamate (VIII):

Formula (VIII)

To a stirred solution of ethanolamine (50.0 g, 0.8186 mol) in dichloromethane (1000 ml), was added triethylamine (124 g, 1.228 mol) at 0°C. After 10 minutes, di-teri-butyl dicarbonate (VII, 214.15 g, 0.9823 mol) was added drop wise at 0°C under continuous stirring. Then reaction mass was allowed to warm to 25°C and stirred further for 3 hours. After completion of reaction, the resulting reaction mixture was poured into water (250 ml) and the organic layer was separated and dried over anhydrous sodium sulfate. The dried organic layer was concentrated under reduced pressure to obtain 130 g of the titled product as colorless oil in 98% yield.

Analysis:

Mass: 162 (M+l); for Molecular Weight of 161.2 and Molecular Formula of C7H15NO3.

1H NMR (400MHz, CDC1₃): δ 4.92(br s,lH), 3.72-3.68(q,2H), 3.30-3.26(q,2H), 2.33(br s,lH), 1.44(s,9H).

Preparation of A⁷-Boc-2-(2-aminoethoxy)isoindoline-l,3-dione (IX):

To a stirred solution of teri;butyl-2-hydroxy-ethylcarbamate (VIII, 50 g, 0.3106 mol) in tetrahydrofuran (500 ml), was added triphenylphosphine (89.5 g, 0.3416 mol) at 25°C. After stirring for 10 minutes, a solution of N-hydroxyphthalimide (50.66 g, 0.3106 mol) in dichloromethane (250 ml) was added to the reaction mass at 25 °C over a period of 10 minutes. After stirring for further 10 minutes, diisopropyl azodicarboxylate (69.1 g, 0.3416 mol) was added to the reaction mass in small portions (exothermic reaction was observed up to 34°C). The resulting reaction mass was stirred further at 25°C. After 16 hours, the reaction mass was concentrated under reduced pressure to obtain colorless oily material. The oily residue was diluted with diisopropyl ether (200 ml) and stirred for 30 minutes. The separated solid was filtered under suction. The filtrate was evaporated under reduced pressure and the residue subjected to di-isopropyl ether treatment (200 ml). This procedure was repeated once again. The filtrate was concentrated to obtain a solid product. The obtained solid was washed with diisopropyl ether (50 ml) and dried under reduced pressure. This solid contains small amount of triphenylphosphine oxide, along with the product. This was used as such for the next reaction without further purification.

Analysis:

Mass: 307.2 (M+l); for Molecular Weight of 306.3 and Molecular Formula of Ci₅Hi₈N₂0₅; 1H NMR of purified material (400MHz, CDC1₃): 7.85-7.25 (m,4H), 5.62(br s,lH), 4.26-4.23(t,2H), 3.46-3.42(q,2H), 1.46(s,9H).

Step 3: Preparation of fert-butyl-[ -(aminooxy) ethyl]carbamate (III):

Formula (III)

To a stirred solution of N-Boc-2-(2-aminoethoxy)isoindoline-l ,3-dione (IX, 97 g, 0.3167 mol) in dichloromethane (970 ml) was added hydrazine hydrate (31.7 g, 0.6334 mol) , at 0°C, drop wise, over a period of 45 minutes and the stirring continued further. After 2 hours, the reaction mass was filtered under suction. Filtrate was washed with water (485 ml), and the organic layer was diluted with an aq. solution of 10% potassium hydrogen sulfate (485 ml) and stirred for 15 minutes. The aqueous layer was separated, neutralized with solid sodium hydrogen carbonate and extracted with dichloromethane (2 x 485 ml). The organic layer was separated, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to obtain colorless oil, this was used as such for further reaction immediately (28g, overall yield of step II and step III was 60%)

Analysis:

Mass: 177.2 (M+l) for Molecular Weight of 176.2 and Molecular Formula of C7H16N2O₃.

Example 2

Synthesis of (25,5R)-jV-(2-aminoethoxy)-6-(sulfooxy)-7-oxo-l,6-diaza-bicvclor3.2.11octane-2- carboxamide (I)

Step 1: Preparation of (25,5R)-iV-(2-Boc-aminoethoxy)-6-(benzyloxy)-7-oxo-l,6-diaza-bicyclo[3.2.1]octane-2-carboxamide (IV):

To a clear solution of sodium (25,5i?)-6-(benzyloxy)-7-oxo-l,6-diazabicyclo[3.2.1]octane-2-carboxylate (II, 42.67 g, 0.143 mol; prepared according to the procedure disclosed in Indian Patent Application No. 699/MUM/2013) in water (426 ml) was added EDC.HC1 (67.1 g, 0.349 mol) at 15°C

under stirring. After 10 minutes, a solution of teri-butyl-[2-(aminooxy) ethyl]carbamate (III, 28.0g, 0.159 mol; prepared as per the literature procedure depicted in Scheme 2) in dimethylformamide (56 ml) was added drop wise at 10°C under continuous stirring. The temperature of the reaction mass was allowed to warm to 25°C and then HOBt (21.5g, 0.159 mol) was added in small portions over a period of 15 minutes and the resulting mixture was further stirred at room temperature for 16 hours. The reaction was continuously monitored using thin layer chromatography using mixture of acetone and hexane (35 :65) as solvent system. After completion of reaction, the resulting mixture was filtered and the residue was washed with water (130 ml). The obtained white residue was suspended in water (130 ml) and the mixture stirred at 50°C for 3 hours. The resulting suspension was filtered, the residue dried under reduced pressure to obtain 51 g of (2S,5R)-N-(2-Boc-aminoethoxy)-6-(benzyloxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1]octane-2-carboxamide (IV) as off white solid in 73% yield.

Analysis:

Mass: 433.4 (M-l ); for Molecular Weight of 434.5 and Molecular Formula of C21H₃0N4O6;

1H-NMR (400MHz, CDC1₃): δ 9.32 (br s, 1H), 7.41 -7.26(m,5H), 5.41(br s, 1H), 5.06-4.88(dd, 2H), 3.98-3.96(d,lH), 3.91-3.90(m,2H), 3.39(m, 1H), 3.31-3.26(m, 2H), 3.04-3.01(d,lH), 2.77-2.74(d, 1H), 2.33-2.28(m, 1H), 2.03-1.93(m, 2H), 1.67-1.64(m, 1H), 1.44(s, 9H);

Purity as determined by HPLC: 99.4%.

Step 2: Preparation of (2S,5R)-iV-(2-Boc-aminoethoxy)-6-(hydroxy)-7-oxo-l,6-diaza-bicyclo[3.2.1]octane-2-carboxamide (V):

A solution of (25,5i?)-N-(2-Boc-aminoethoxy)-6-(benzyloxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1] octane-2-carboxamide (IV, 38 g, 0.0875 mol) in a mixture of dimethylformamide and dichloromethane (2: 8, 76 ml: 304 ml), containing 10% Pd/C (7.6 g, 50% wet) was hydrogenated at 50 psi hydrogen atmosphere at 25°C for 3 hours. The resulting mixture was filtered through a celite pad. The residue was washed with dichloromethane (75 ml). The solvent from the combined filtrate was evaporated

under reduced pressure to obtain 30 g (25,5i?)-N-(2-Boc-aminoethoxy)-6-(hydroxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide (V) as an oil, which was used as such for the next reaction without further purification.

Analysis:

Mass: 343.3 (M-l ) for Molecular Weight of 344.3 and Molecular Formula of C14H24N4O6.

Step 3: Preparation of (25,5R)-iV-(2-Boc-aminoethoxy)-6-(sulfooxy)-7-oxo-l,6-diaza-bicyclo[3.2.1]octane-2-carboxamide,tetrabutyl ammonium salt (VI):

To a stirred solution of (25,5i?)-N-(2-Boc-aminoethoxy)-6-(hydroxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide (V, 30.0 g, 0.0875 mol) in dimethylformamide (150 ml) was added sulphur trioxide dimethylformamide complex (16.06 g, 0.105 mol) in one portion, at 10°C. The reaction mass was stirred at the same temperature for 30 minutes and then allowed to warm to room temperature. After 2 hours, a solution of tetrabutylammonium acetate (31.6 g, 0.105 mol) in water (95 ml) was slowly added to the reaction mixture and stirred for another 2 hours. The solvent from the reaction mixture was evaporated under reduced pressure to obtain an oily residue. The oily mass was co-evaporated with xylene (2 x 60 ml) to obtain thick mass. This mass was partitioned between 1 : 1 mixture of dichloromethane (300 ml) and water (300 ml). The organic layer was separated and the aqueous layer re-extracted with dichloromethane (150 ml). The combined organic extracts were washed with water (3 x 150 ml) and dried over anhydrous sodium sulphate. The solvent was evaporated under reduced pressure and the resulting oily mass was triturated with ether (3 x 60 ml). Each time the ether layer was decanted and the residue was finally concentrated under reduced pressure to obtain the sticky mass. The so obtained material was purified by column chromatography over silica gel using mixture of methanol and dichloromethane as elution solvent. The solvent from the combined fractions was evaporated to obtain 47.5 g of (25,5i?)-N-(2-Boc-aminoethoxy)-6-(sulfooxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide,tetrabutyl ammonium salt as white foam in 70% yield.

Analysis:

Mass: 423.4 (M-l) as free sulphonic acid; for Molecular Weight of 665.9 and Molecular Formula of C₃0H59N5O9 S;

1H- NMR (400MHz, CDC1₃): δ 9.52(br s, 1H), 5.53(br s, 1H), 4.33(s, 1H), 3.95-3.92(m,3H), 3.37-3.27(m, 1 1H), 2.87-2.84(d, 1H), 2.35-2.30(m, 1H), 2.17(m, 1H), 1.96-1.88(m, 2H), 1.74-1.60(m,8 H), 1.47-1.40(m, 17H), 1.02-0.98(m, 12H).

Step 4: Preparation of (2S R)-iV-(2-aminoethoxy)-6-(sulfooxy)-7-oxo-l,6-diaza-bicyclo[3.2.1]octane-2-carboxamide (I):

Formula (I)

To a stirred solution of (2S,5i?)-N-(2-Boc-aminoethoxy)-6-(sulfooxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide, tetrabutyl ammonium salt (VI, 17 g, 0.0225 mol) in dichloromethane (85 ml) was added trifluoroacetic acid (85 ml) drop wise at -10°C over a period of 45 minutes. The resulting mass was further stirred at same temperature for 1 hour. The resulting reaction mixture was poured into cyclohexane (850 ml), stirred well for 30 minutes and the separated oily layer was collected. This procedure was repeated one more time and finally the separated oily layer was added to tert-butyl methyl ether (170 ml) under vigorous stirring at 25°C. The ether layer was removed by decantation from the precipitated solid. This procedure was repeated twice again with tert-butyl methyl ether (2 x 170 ml). The solid thus obtained was stirred with fresh dichloromethane (170 ml) for 30 minutes and filtered. The residual solid was dried at 45°C under reduced pressure to yield 7.3g of the titled compound in crude form. The obtained solid was further dissolved in water, (7.3 ml) and to this solution was added basic resin (Amberlyst A-26 -OH ion exchange resin, 4.4 g) under stirring. After 0.5 hour, the resin was filtered and to the filtrate isopropanol (51 ml) was added slowly at 25°C. The solution was further stirred for 12 hours. The separated solid was filtered and washed with additional isopropanol (7.5 ml) and dried under reduced pressure to obtain 4.3 g of (2S ,5R)-N-(2-aminoethoxy)-6-(sulfooxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide as off-white solid in 52 % yield.

Analysis:

Mass: 323.1 (M-l); for Molecular Weight of 324.31 and Molecular Formula of C₉H16N4O7S; 1H-NMR (400MHz, D₂0): δ 4.07-4.06(d, 1H), 4.05-4.03(t, 2H), 3.96-3.94(d, 1H), 3.20(br s, 1H), 3.16-3.13(t, 2H), 3.02-2.99(d, 1H), 2.04-1.68(m, 4H);

Purity as determined by HPLC: 94.88%.

REF

http://www.pewtrusts.org/~/media/assets/2015/02/antibioticsinnovationproject_datatable_201502_v3.pdf?la=en

/////////////IN2015MU287, WO-2016120752, nacubactam, WOCKHARDT, NEW PATENT, WK ?, WK-?, WK?,  CAS 1452458-86-4, C₉ H₁₆ N₄ O₇ S, 324.31, Beta lactamase inhibitor, Roche, Meiji Seika Pharma,  Fedora Pharmaceuticals, nacubactam hydrate , PHASE 1, A diazabicyclooctane beta-lactamase inhibitor, bacterial infection, July 2016,  phase 1 clinical development, RG-6080, 1452458-86-4, FPI-1459,  OP-0595, Phase I ,  β-lactamase inhibitor, bacterial infections, Fedora parmaceuticals, Meiji Seika Pharma

NCCONC(=O)[C@@H]2CC[C@@H]1C[N@]2C(=O)N1OS(=O)(=O)O

Dolutegravir

• Soltegravir

2H-Pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxamide, N-[(2,4-difluorophenyl)methyl]-3,4,6,8,12,12a-hexahydro-7-hydroxy-4-methyl-6,8-dioxo-, (4R,12aS)

(3R,11aS)—N-[(2,4-Difluorophenyl)methyl]-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide

(4R,12aS)-N-(2,4-difluorobenzyl)-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxamide
Trade Name:Tivicay
Synonym:GSK1349572, S-349572, GSK572
Date of Approval: August 12, 2013 (US)
Indication:HIV infection
Drug class: Integrase strand transfer inhibitor
Company: ViiV Healthcare,GlaxoSmithKline

INNOVATOR …ViiV Healthcare 
CAS number: 1051375-16-6

1051375-19-9 (Dolutegravir Sodium)

MF:C20H19F2N3O5
MW:419.4

Chemical Name: (4R,12aS)-N-[(2,4-difluorophenyl)methyl]-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a- hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxamide
Patent: US8129385
Patent expiration date: Oct 5, 2027
PCT patent application: W02006116764

ドルテグラビルナトリウム
Dolutegravir Sodium

C₂₀H₁₈F₂N₃NaO₅ : 441.36
[1051375-19-9]

Dolutegravir (DTG, GSK1349572) is an integrase inhibitor being developed for the treatment of human immunodeficiency virus (HIV)-1 infection by GlaxoSmithKline (GSK) on behalf of Shionogi-ViiV Healthcare LLC. DTG is metabolized primarily by uridine diphosphate glucuronyltransferase (UGT)1A1, with a minor role of cytochrome P450 (CYP)3A, and with renal elimination of unchanged drug being extremely low (< 1% of the dose).

Dolutegravir sodium was approved by the U.S. Food and Drug Administration (FDA) on Aug 12, 2013, then approved by European Medicine Agency (EMA) on Jan 16, 2014, and approved by Pharmaceuticals and Medical Devices Agency of Japan (PMDA) on Mar 24, 2014, then approved by Center For Drug Evaluation (CFDA) on Dec 30, 2015. It was co-developed by GlaxoSmithKline & ViiV Healthcare Corporation, then marketed as Tivicay^® by ViiV Healthcare in the US and EU and by GlaxoSmithKline & ViiV Healthcare Corporation in JP.

Dolutegravir sodium is an integrase inhibitor which blocks HIV replication by preventing the viral DNA from integrating into the genetic material of human immune cells (T-cells). This step is essential in the HIV replication cycle and is also responsible for establishing chronic infection. It is in combination with other antiretroviral agents for the treatment of HIV-1 infection in adults and children aged 12 years and older and weighing at least 40 kg.

Tivicay^® is available as film-coated tablet for oral use, containing 50 mg of free Dolutegravir. The recommended dose is 50 mg Dolutegravir once daily without regards to meals.

APPROVALS

CLIP

The European Commission has on 21 January 2014 Dolutegravir (Tivicay, ViiV) permit as part of combination therapy for the treatment of HIV-infected persons over the age of 12 years.Dolutegravir (Tivicay, ViiV) is an integrase inhibitor, in combination with other antiretroviral drugs in adults and adolescents can be used from 12 years for the treatment of HIV infection.

Source: Communication from the European Commission

Dolutegravir^[1] is a FDA-approved drug^[2] for the treatment of HIV infection. Dolutegravir is an integrase inhibitor. Known as S/GSK1349572 or just “572” the drug is marketed as Tivicay^[3] by GlaxoSmithKline (GSK). In February, 2013 the Food and Drug Administration announced that it would fast track dolutegravir’s approval process.^[4] On August 13, 2013, dolutegravir was approved by the FDA. On November 4, 2013, dolutegravir was approved by Health Canada.^[5]

The oral HIV integrase inhibitor S-349572 was originated by Shionogi-GlaxoSmithKline and Shionogi-ViiV Healthcare. In 2013, the product was approved and launched in the U.S. for the treatment of HIV-1 in adults and children aged 12 years and older, in combination with other antiretroviral agents. A positive opinion was received in the E.U for this indication and, in 2014, approval was attained in Europe for this indication. Registration is pending in Japan.

In 2013, orphan drug designation in Japan was assigned to the compound.

Dolutegravir is approved for use in a broad population of HIV-infected patients. It can be used to treat HIV-infected adults who have never taken HIV therapy (treatment-naïve) and HIV-infected adults who have previously taken HIV therapy (treatment-experienced), including those who have been treated with other integrase strand transfer inhibitors. Tivicay is also approved for children ages 12 years and older weighing at least 40 kilograms (kg) who are treatment-naïve or treatment-experienced but have not previously taken other integrase strand transfer inhibitors.^[6]

Dolutegravir has also been compared head-to-head with a preferred regimen from the DHHS guidelines in each of the three classes (i.e. 1.) nuc + non-nuc, 2.) nuc + boosted PI, and 3.) nuc + integrase inhibitor).

SPRING-2 compared dolutegravir to another integrase inhibitor, raltegravir, with both coformulated with a choice of TDF/FTC orABC/3TC. After 48 weeks of treatment 88% of those on dolutegravir had less than 50 copies of HIV per mL compared to 85% in the raltegravir group, thus demonstrating non-inferiority.^[9]

The FLAMINGO study has been presented at scientific meetings but as of early 2014 has not yet been published. It is an open-label trial of dolutegravir versus darunavir boosted with ritonavir. In this trial 90% of those on dolutegravir based regimens had viral loads < 50 at 48 weeks compared to 83% in the darunavir/r.^[10] This 7% difference was statistically significant for superiority of the dolutegravir based regimens.

Another trial comparing dolutegravir to efavirenz, SINGLE, was the first trial to show statistical superiority to an efavirenz/FTC/TDF coformulated regimen for treatment naive patients.^[11] After 48 weeks of treatment, 88% of the dolutegravir group had HIV RNA levels < 50 copies / mL versus 81% of the efavirenz group. This has led one commentator to predict that it may replace efavirenz as the first line choice for initial therapy as it can also be formulated in one pill, once-a-day regimens.^[12]

Doultegravir has also been studied in patients who have been on previous antiretroviral medications. The VIKING trial looked at patients who had known resistance to the first generation integrase inhibitor raltegravir. After 24 weeks 41% of patients on 50mg dolutegravir once daily and 75% of patients on 50mg twice daily (both along with an optimized background regimen) achieved an HIV RNA viral load of < 50 copies per mL. This demonstrated that there was little clinical cross-resistance between the two integrase inhibitors. ^[13]

Dolutegravir (also known as S/GSK1349572), a second-generation integrase inhibitor under development by GlaxoSmithKline and its Japanese partner Shionogi for the treatment of HIV infection, was given priority review status from the US Food and Drug Administration (FDA) in February, 2013.

GlaxoSmithKline  marketed the first HIV drug Retrovir in 1987 before losing out to Gilead Sciences Inc. (GILD) as the world’s biggest maker of AIDS medicines. The virus became resistant to Retrovir when given on its own, leading to the development of therapeutic cocktails.

The new once-daily drug Dolutegravir, which belongs to a novel class known as integrase inhibitors that block the virus causing AIDS from entering cells, is owned by ViiV Healthcare, a joint venture focused on HIV in which GSK is the largest shareholder.

Raltegravir (brand name Isentress) received approval by the U.S. Food and Drug Administration (FDA) on 12 October 2007, the first of a new class of HIV drugs, the integrase inhibitors, to receive such approval. it is a potent and well tolerated antiviral agent.  However, it has the limitations of twice-daily dosing and a relatively modest genetic barrier to the development of resistance, prompting the search for agents with once-daily dosing.

Elvitegravir, approved by the FDA on August 27, 2012 as part of theelvitegravir/cobicistat/tenofovir disoproxil fumarate/emtricitabine fixed-dose combination pill (Quad pill, brand name Stribild) has the benefit of being part of a one-pill, once-daily regimen, but suffers from extensive cross-resistance with raltegravir.

DOLUTEGRAVIR

Gilead’s Atripla (Emtricitabine/Tenofovir/efavirenz), approved in 2006 with loss of patent protection in 20121, is the top-selling HIV treatment. The $3.2 billion medicine combines three drugs in one pill, two compounds that make up Gilead’s Truvada (Emtricitabine/Tenofovir) and Bristol- Myers Squibb Co.’s Sustiva (Efavirenz).

A three-drug combination containing dolutegravir and ViiV’s older two-in-one treatment Epzicom(Abacavir/Lamivudine, marketed outside US as Kivexa) proved better than Gilead’s market-leading Atripla  in a clinical trial released in July, 2012 (See the Full Conference Report Here), suggesting it may supplant the world’s best-selling AIDS medicine as the preferred front-line therapy. In the latest Phase III study, after 48 weeks of treatment, 88% of patients taking the dolutegravir-based regimen had reduced viral levels to the goal compared with 81% of patients taking Atripla. More patients taking Atripla dropped out of the study because of adverse events compared with those taking dolutegravir — 10% versus just 2% — which was the main driver of the difference in efficacy. The result was the second positive final-stage clinical read-out for dolutegravir, following encouraging results against U.S. company Merck & Co’s rival Isentress in April, 2012 (See the Conference Abstract Here)..

Dolutegravir is viewed by analysts as a potential multibillion-dollar-a-year seller, as its once-daily dosing is likely to be attractive to patients. The FDA is scheduled to issue a decision on the drug’s approval by August 17。

TIVICAY contains dolutegravir, as dolutegravir sodium, an HIV INSTI. The chemical name of dolutegravir sodium is sodium (4R,12aS)-9-{[(2,4-difluorophenyl)methyl]carbamoyl}-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazin-7-olate. The empirical formula is C₂₀H₁₈F₂N₃NaO₅ and the molecular weight is 441.36 g/mol. It has the following structural formula:

Dolutegravir sodium is a white to light yellow powder and is slightly soluble in water.

Each film-coated tablet of TIVICAY for oral administration contains 52.6 mg of dolutegravir sodium, which is equivalent to 50 mg dolutegravir free acid, and the following inactive ingredients: D-mannitol, microcrystalline cellulose, povidone K29/32, sodium starch glycolate, and sodium stearyl fumarate. The tablet film-coating contains the inactive ingredients iron oxide yellow, macrogol/PEG, polyvinyl alcohol-part hydrolyzed, talc, and titanium dioxide.

DOLUTEGRAVIR

http://blog.sina.com.cn/s/blog_de171b9b0101a1ah.html  BELOW

1H NMR (Estimated) for Dolutegravir

INTRODUCTION

Among viruses, human immunodeficiency virus (HIV), a kind of retrovirus, is known to cause acquired immunodeficiency syndrome (AIDS). The therapeutic agent for AIDS is mainly selected from a group of reverse transcriptase inhibitors (e.g., AZT, 3TC) and protease inhibitors (e.g., Indinavir), but they are proved to be accompanied by side effects such as nephropathy and the emergence of resistant viruses. Thus, the development of anti-HIV agents having the other mechanism of action has been desired.

On the other hand, a combination therapy is reported to be efficient in treatment for AIDS because of the frequent emergence of the resistant mutant. Reverse transcriptase inhibitors and protease inhibitors are clinically used as an anti-HIV agent, however agents having the same mechanism of action often exhibit cross-resistance or only an additional activity. Therefore, anti-HIV agents having the other mechanism of action are desired.

Under the circumstances above, an HIV integrase inhibitor has been focused on as an anti-HIV agent having a novel mechanism of action (Ref: Patent Documents 1 and 2). As an anti-HIV agent having such a mechanism of action, known are carbamoyl-substituted hydroxypyrimidinone derivative (Ref: Patent Documents 3 and 4) and carbamoyl-substituted hydroxypyrrolidione derivative (Ref: Patent Document 5). Further, a patent application concerning carbamoyl-substituted hydroxypyridone derivative has been filed (Ref: Patent Document 6, Example 8).

Other known carbamoylpyridone derivatives include 5-alkoxypyridine-3-carboxamide derivatives and γ-pyrone-3-carboxamide derivatives, which are a plant growth inhibitor or herbicide (Ref: Patent Documents 7-9).

Other HIV integrase inhibitors include N-containing condensed cyclic compounds (Ref: Patent Document 10).

• [Patent Document 1] WO03/0166275
• [Patent Document 2] WO2004/024693
• [Patent Document 3] WO03/035076
• [Patent Document 4] WO03/035076
• [Patent Document 5] WO2004/004657
• [Patent Document 6] JP Patent Application 2003-32772
• [Patent Document 7] JP Patent Publication 1990-108668
• [Patent Document 8] JP Patent Publication 1990-108683
• [Patent Document 9] JP Patent Publication 1990-96506
• [Patent Document 10] WO2005/016927
• Patent Document 1 describes compounds (I) and (II), which are useful as anti-HIV drugs and shown by formulae:
  This document describes the following reaction formula as a method of producing compound (I).
  Furthermore, Patent Documents 2 to 6 describe the following reaction formula as an improved method of producing compound (I).
  [PATENT DOCUMENTS]
  • • [Patent Document 1] International publication No.2006/116764 pamphlet
    • [Patent Document 2] International publication No.2010/011812 pamphlet
    • [Patent Document 3] International publication No.2010/011819 pamphlet
    • [Patent Document 4] International publication No.2010/068262 pamphlet
    • [Patent Document 5] International publication No.2010/067176 pamphlet
    • [Patent Document 6] International publication No.2010/068253 pamphlet
    • [Patent Document 7] US Patent 4769380A
    • [Patent Document 8] International applicationPCT/JP2010/055316

  [NON-PATENT DOCUMENTS]

  • • [Non-Patent Document 1] Journal of Organic Chemistry, 1991, 56(16), 4963-4967
    • [Non-Patent Document 2] Science of Synthesis, 2005, 15, 285-387
    • [Non-Patent Document 3] Journal of Chemical Society Parkin Transaction. 1, 1997, Issue. 2, 163-169

A clip and its own references

Dolutegravir sodium (Tivicay®), developed and marketed by GlaxoSmithKline,45 was approved by the FDA in August 2013 as a novel integrase inhibitor for the treatment of HIV infection.46 Dolutegravir was fast-tracked by the FDA in February 2012,47 and joins an important class of drugs known as Integrase Strand Transfer inhibitors (INSTi’s).48 INSTi’s are characterized by their two-metal-chelating scaffolds, which are known to chelate Mg2+ cofactors in the enzyme active site,49, 50 interrupting function of HIV-1 integrase, which is essential for replication of viral DNA into host chromatin.49-51,52 Other drugs in this class, raltegravir and elvitegravir, are known to require either high dosages53 or PK boosting agents,54 respectively, with raltegravir also exhibiting substantial loss of potency in several major HIV-1 integrase mutation pathways.55 Dolutegravir was pursued with the goal of developing a INSTi with a once-daily, low-dosage treatment with improved resistance profile and without the
need for the use of a PK boosting agent.51, 56 Dolutegravir sodium has been approved for treating a broad
population of HIV-infected patients, including adults undergoing their first treatment as well as those
who have been treated with other integrase transfer strand inhibiting agents.46 The most likely process-scale synthesis of dolutegravir sodium, as described in Scheme 8, began with benzyl protection and alkylation of pyrone 46 with benzaldehyde, yielding alcohol 47 in 74% over 2 steps (Scheme 8).57, 58 Alcohol mesylation and in-situ elimination provided the styrenyl olefin 48 in 94% yield, which further underwent an oxidative cleavage of the olefin to generate 49 by sequential addition of RuCl3/NaIO4 and NaClO2 (56% overall yield). Treatment of pyranone 49 with 3-amino-propane-2-diol (50) in ethanol at elevated temperatures delivered the corresponding pyridinone in 83% yield, and this was followed by esterification and sodium periodate-mediated diol cleavage to furnish intermediate 51 in 71% overall yield across the two-step sequence.57, 58 Next, the key ring-forming step in the
synthesis of dolutegravir sodium consisted of cyclization of 51 with (R)-3-amino-butan-1-ol, a process which relies on substrate control to provide the desired tricyclic carbamoylpyridone system 52 in high stereoselectivity (20/1 in favor of the desired isomer).51 Previously, cyclization of systems such as 51 with unsubstituted amino alcohols were found to yield a mixture of diastereomeric products, therefore indicating the pivotal role of the chiral amino alcohol in influencing stereochemical bias during the overall cyclization step.51, 56 In practice, reaction of 51 with (R)-3-amino-butan-1-ol at 90 °C led to isolation of a single cyclization product 52, after recrystallization from EtOAc.57, 58 From 52, Nbromosuccinimide (NBS) bromination and subsequent treatment with amine 53 under palladiumcatalyzed
amidocarbonylative conditions led to amide 54 in 75% yield over 2 steps. Finally, removal of the benzyl group and subsequent crystallization using sodium hydroxide in water and ethanol provided dolutegravir sodium (VII) in 99% yield.57, 58

 

45 Johns, B. A.; Kawasuji, T.; Taishi, T.; Taoda, Y. WO Patent 2006116764A1, 2006.
46. http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm364744.htm.
47. https://newdrugapprovals.org/2013/07/16/dolutegravir-biggest-rival-to-worlds-best-selling-hivdrug-atripla-may-get-fda-approval-by-august-2013/.
48. Pendri, A.; Meanwell, N. A.; Peese, K. M.; Walker, M. A. Expert Opin. Ther. Pat. 2011, 21,1173.
49. Johns, B. A.; Svolto, A. C. Expert Opin. Ther. Pat. 2008, 18, 1225.60
50. Johns, B. A.; Weatherhead, J. G.; Allen, S. H.; Thompson, J. B.; Garvey, E. P.; Foster, S. A.;
Jeffrey, J. L.; Miller, W. H. Bioorg. Med. Chem. Lett. 2009, 19, 1802.
51. Johns, B. A.; Kawasuji, T.; Weatherhead, J. G.; Taishi, T.; Temelkoff, D. P.; Yoshida, H.;Akiyama, T.; Taoda, Y.; Murai, H.; Kiyama, R.; Fuji, M.; Tanimoto, N.; Jeffrey, J.; Foster, S.A.; Yoshinaga, T.; Seki, T.; Kobayashi, M.; Sato, A.; Johnson, M. N.; Garvey, E. P.; Fujiwara,
T. J. Med. Chem. 2013, 56, 5901.
52. Kawasuji, T.; Johns, B. A.; Yoshida, H.; Taishi, T.; Taoda, Y.; Murai, H.; Kiyama, R.; Fuji, M.;Yoshinaga, T.; Seki, T.; Kobayashi, M.; Sato, A.; Fujiwara, T. J. Med. Chem. 2012, 55, 8735.
53. Lennox, J. L.; De Jesus, E.; Lazzarin, A.; Pollard, R. B.; Valdez Ramalho Madruga, J.; Berger,D. S.; Zhao, J.; Xu, X.; Williams-Diaz, A.; Rodgers, A. J.; Barnard, R. J. O.; Miller, M. D.; DiNubile, M. J.; Nguyen, B.-Y.; Leavitt, R.; Sklar, P. Lancet 2009, 374, 796.
54. Ramanathan, S.; Mathias, A. A.; German, P.; Kearney, B. P. Clin. Pharmacokinet. 2011, 50,229.
55. Ceccherini-Silberstein, F.; Malet, I.; D’Arrigo, R.; Antinori, A.; Marcelin, A.-G.; Perno, C.-F.AIDS Rev. 2009, 11, 17.
56. Kawasuji, T.; Johns, B. A.; Yoshida, H.; Weatherhead, J. G.; Akiyama, T.; Taishi, T.; Taoda, Y.;Mikamiyama-Iwata, M.; Murai, H.; Kiyama, R.; Fuji, M.; Tanimoto, N.; Yoshinaga, T.; Seki, T.;Kobayashi, M.; Sato, A.; Garvey, E. P.; Fujiwara, T. J. Med. Chem. 2013, 56, 1124.
57. Johns, B. A.; Duan, M.; Hakogi, T. WO Patent 2010068262A1, 2010.
58. Yoshida, H.; Taoda, Y.; Johns, B. A. WO Patent 2010068253A1, 2010.

CLIPS

Dolutegravir synthesis (EP2602260, 2013). LiHMDS as the non-nucleophilic strong base pulling compound 1 carbonyl group proton alpha position with an acid chloride after 2 and ring closure reaction to obtain 3 , 3 via primary amine 4 ring opening ring closure to obtain 5 , NBS the bromine under acidic conditions to obtain aldehyde acetal becomes 6 , 6 of the aldehyde and amino alcohols 7 and turn off the condensation reaction obtained by the ring 8 , alkaline hydrolysis 8 of bromine into a hydroxyl group and hydrolyzable ester obtained 9 after the 10 occurred acid condensation Dolutegravir.

CLIPS

Synthesis of Dolutegravir (S/GSK1349572, GSK1349572)

SYNTHESIS

2H-Pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxamide, N-[(2,4-difluorophenyl)methyl]-3,4,6,8,12,12a-hexahydro-7-hydroxy-4-methyl-6,8-dioxo-, (4R,12aS) ………..dolutegravir

PATENT

US8129385

Desired isomer

Example Z-1

(3R,11aS)—N-[(2,4-Difluorophenyl)methyl]-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide sodium salt

a)

(3R,11aS)—N-[(2,4-Difluorophenyl)methyl]-3-methyl-5,7-dioxo-6-[(phenylmethyl)oxy]-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide. To a solution of 16a (409 mg, 0.87 mmol) in dichloroethane (20 mL) was added (2R)-2-amino-1-propanol (0.14 mL, 1.74 mmol) and 10 drops of glacial acetic acid. The resultant solution was heated at reflux for 2 h. Upon cooling, Celite was added to the mixture and the solvents removed in vacuo and the material was purified via silica gel chromatography (2% CH₃OH/CH₂Cl₂ gradient elution) to give (3R,11aS)—N-[(2,4-difluorophenyl)methyl]-3-methyl-5,7-dioxo-6-[(phenylmethyl)oxy]-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide (396 mg, 92%) as a glass. ¹H NMR (CDCl₃) δ 10.38 (m, 1H), 8.42 (s, 1H), 7.54-7.53 (m, 2H), 7.37-7.24 (m, 4H), 6.83-6.76 (m, 2H), 5.40 (d, J=10.0 Hz, 1H), 5.22 (d, J=10.0 Hz, 1H), 5.16 (dd, J=9.6, 6.0 Hz, 1H), 4.62 (m, 2H), 4.41 (m, 1H), 4.33-4.30 (m, 2H), 3.84 (dd, J=12.0, 10.0 Hz, 1H), 3.63 (dd, J=8.4, 7.2 Hz, 1H), 1.37 (d, J=6.0 Hz, 3H); ES⁺MS: 496 (M+1).

b)

(3R,11aS)—N-[(2,4-Difluorophenyl)methyl]-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide sodium salt. To a solution of (3R,11aS)—N-[(2,4-difluorophenyl)methyl]-3-methyl-5,7-dioxo-6-[(phenylmethyl)oxy]-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide (396 mg, 0.80 mmol) in methanol (30 mL) was added 10% Pd/C (25 mg). Hydrogen was bubbled through the reaction mixture via a balloon for 2 h. The resultant mixture was filtered through Celite with methanol and dichloromethane.

The filtrate was concentrated in vacuo to give (3R,11aS)—N-[(2,4-difluorophenyl)methyl]-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide , DOLUTEGRAVIR   as a pink tinted white solid (278 mg, 86%).

¹H NMR (CDCl₃) δ 11.47 (m, 1H), 10.29 (m, 1H), 8.32 (s, 1H), 7.36 (m, 1H), 6.82 (m, 2H), 5.31 (dd, J=9.6, 3.6 Hz, 1H), 4.65 (m, 2H), 4.47-4.38 (m, 3H), 3.93 (dd, J=12.0, 10.0 Hz, 1H), 3.75 (m, 1H), 1.49 (d, J=5.6 Hz, 3H); ES⁺ MS: 406 (M+1).

DOLUTEGRAVIR NA SALT

The above material (278 mg, 0.66 mmol) was taken up in ethanol (10 mL) and treated with 1 N sodium hydroxide (aq) (0.66 ml, 0.66 mmol). The resulting suspension was stirred at room temperature for 30 min. Ether was added and the liquids were collected to provide the sodium salt of the title compound as a white powder (291 mg, 99%). ¹H NMR (DMSO-d₆) δ 10.68 (m, 1H), 7.90 (s, 1H), 7.35 (m, 1H), 7.20 (m, 1H), 7.01 (m, 1H), 5.20 (m, 1H), 4.58 (m, 1H), 4.49 (m, 2H), 4.22 (m, 2H), 3.74 (dd, J=11.2, 10.4 Hz, 1H), 3.58 (m, 1H), 1.25 (d, J=4.4 Hz, 3H).

UNDESIRED ISOMER

Example Z-9

(3S,11aR)—N-[(2,4-Difluorophenyl)methyl]-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide sodium salt

The title compound was made in two steps using a similar process to that described in example Z-1. 16a (510 mg, 1.08 mmol) and (25)-2-amino-1-propanol (0.17 mL, 2.17 mmol) were reacted in 1,2-dichloroethane (20 mL) with acetic acid to give (3S,11aR)—N-[(2,4-difluorophenyl)methyl]-3-methyl-5,7-dioxo-6-[(phenylmethyl)oxy]-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide (500 mg, 93%). This material was hydrogenated in a second step as described in example Z-1 to give (3S,11aR)—N-[(2,4-Difluorophenyl)methyl]-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide (386 mg, 94%) as a tinted white solid. ¹H NMR (CDCl₃) δ 11.46 (m, 1H), 10.28 (m, 1H), 8.32 (s, 1H), 7.35 (m, 1H), 6.80 (m, 2H), 5.30 (dd, J=10.0, 4.0 Hz, 1H), 4.63 (m, 2H), 4.48-4.37 (m, 3H), 3.91 (dd, J=12.0, 10.0 Hz, 1H), 3.73 (m, 1H), 1.48 (d, J=6.0 Hz, 3H); ES⁺ MS: 406 (M+1). This material (385 mg, 0.95 mmol) was treated with sodium hydroxide (0.95 mL, 1.0 M, 0.95 mmol) in ethanol (15 mL) as described in example Z-1 to provide its corresponding sodium salt (381 mg, 94%) as a white solid. ¹H NMR (DMSO-d₆) δ 10.66 (m, 1H), 7.93 (s, 1H), 7.33 (m, 1H), 7.20 (m, 1H), 7.01 (m, 1H), 5.19 (m, 1H), 4.59 (m, 1H), 4.48 (m, 2H), 4.22 (m, 2H), 3.75 (m, 1 H), 3.57 (m, 1H), 1.24 (d, J=5.6 Hz, 3H).

SYNTHESIS OF INTERMEDIATES

IN ABOVE SCHEME SYNTHESIS UPTO COMPD 9 MAY BE USEFUL IN SYNTHESIS BUT READERS DISCRETION IS SOUGHT IN THIS ?????????????????

1) Maltol 1 (189 g, 1.5 mol) was dissolved in dimethylformamide (1890 ml), and benzyl bromide (184 ml, 1.5 mol) was added. After the solution was stirred at 80° C. for 15 minutes, potassium carbonate (228 g, 1.65 mol) was added, and the mixture was stirred for 1 hour. After the reaction solution was cooled to room temperature, an inorganic salt was filtered, and the filtrate was distilled off under reduced pressure. To the again precipitated inorganic salt was added tetrahydrofuran (1000 ml), this was filtered, and the filtrate was distilled off under reduced pressure to obtain the crude product (329 g, >100%) of 3-benzyloxy-2-methyl-pyran-4-one 2 as a brown oil.

NMR (CDCl₃) δ: 2.09 (3H, s), 5.15 (2H, s), 6.36 (1H, d, J=5.6 Hz), 7.29-7.41 (5H, m), 7.60 (1H, d, J=5.6 Hz).

2) The compound 2 (162.2 g, 750 mmol) was dissolved in ethanol (487 ml), and aqueous ammonia (28%, 974 ml) and a 6N aqueous sodium hydroxide solution (150 ml, 900 mmol) were added. After the reaction solution was stirred at 90° C. for 1 hour, this was cooled to under ice-cooling, and ammonium chloride (58 g, 1080 mmol) was added. To the reaction solution was added chloroform, this was extracted, and the organic layer was washed with an aqueous saturated sodium bicarbonate solution, and dried with anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, isopropyl alcohol and diethyl ether were added to the residue, and precipitated crystals were filtered to obtain 3-benzyloxy-2-methyl-1H-pyridine-4-one 3 (69.1 g, 43%) as a pale yellow crystal.

NMR (DMSO-d₆) δ: 2.05 (3H, s), 5.04 (2H, s), 6.14 (1H, d, J=7.0 Hz), 7.31-7.42 (5H, m), 7.46 (1H, d, J=7.2 Hz), 11.29 (1H, brs).

3) The above compound 3 (129 g, 699 mmol) was suspended in acetonitrile (1300 ml), and N-bromosuccinic acid imide (117 g, 659 mmol) was added, followed by stirring at room temperature for 90 minutes. Precipitated crystals were filtered, and washed with acetonitrile and diethyl ether to obtain 3-benzyloxy-5-bromo-2-methyl-pyridine-4-ol 4 (154 g, 88%) as a colorless crystal.

NMR (DMSO-d₆) δ: 2.06 (3H, s), 5.04 (2H, s), 7.32-7.42 (5H, m), 8.03 (1H, d, J=5.5 Hz), 11.82 (1H, brs).

4) To a solution of the compound 4 (88 g, 300 mmol), palladium acetate (13.4 g, 60 mmol) and 1,3-bis(diphenylphosphino)propane (30.8 g, 516 mmol) in dimethylformamide (660 ml) were added methanol (264 ml) and triethylamine (210 ml, 1.5 mol) at room temperature. The interior of a reaction vessel was replaced with carbon monoxide, and the material was stirred at room temperature for 30 minutes, and stirred at 80 degree for 18 hours. A vessel to which ethyl acetate (1500 ml), an aqueous saturated ammonium chloride solution (1500 ml) and water (1500 ml) had been added was stirred under ice-cooling, and the reaction solution was added thereto. Precipitates were filtered, and washed with water (300 ml), ethyl acetate (300 ml) and diethyl ether (300 ml) to obtain 5-benzyloxy-4-hydroxy-6-methyl-nicotinic acid methyl ester 5 (44.9 g, 55%) as a colorless crystal.

NMR (DMSO-d₆) δ: 2.06 (3H, s), 3.72 (3H, s), 5.02 (2H, s), 7.33-7.42 (5H, m), 8.07 (1H, s).

5) After a solution of the compound 5 (19.1 g, 70 mmol) in acetic anhydride (134 ml) was stirred at 130° C. for 40 minutes, the solvent was distilled off under reduced pressure to obtain 4-acetoxy-5-benzyloxy-6-methyl-nicotinic acid methyl ester 6 (19.9 g, 90%) as a flesh colored crystal.

NMR (CDCl₃) δ: 2.29 (3H, s), 2.52 (3H, s), 3.89 (3H, s), 4.98 (2H, s), 7.36-7.41 (5H, m), 8.85 (1H, s).

6) To a solution of the compound 6 (46.2 g, 147 mmol) in chloroform (370 ml) was added metachloroperbenzoic acid (65%) (42.8 g, 161 mmol) in portions under ice-cooling, and this was stirred at room temperature for 90 minutes. To the reaction solution was added a 10% aqueous potassium carbonate solution, and this was stirred for 10 minutes, followed by extraction with chloroform. The organic layer was washed with successively with a 10% aqueous potassium carbonate solution, an aqueous saturated ammonium chloride solution, and an aqueous saturated sodium chloride solution, and dried with anhydrous sodium sulfate. The solvent was distilled off under induced pressure, and the residue was washed with diisopropyl ether to obtain 4-acetoxy-5-benzyloxy-6-methyl-1-oxy-nicotinic acid methyl ester 7 (42.6 g, 87%) as a colorless crystal.

NMR (CDCl₃) δ: 2.30 (3H, s), 2.41 (3H, s), 3.90 (3H, s), 5.02 (2H, s), 7.37-7.39 (5H, m), 8.70 (1H, s).

7) To acetic anhydride (500 ml) which had been heated to stir at 130° C. was added the compound 7 (42.6 g, 129 mmol) over 2 minutes, and this was stirred for 20 minutes. The solvent was distilled off under reduced pressure to obtain 4-acetoxy-6-acetoxymethyl-5-benzyloxy-nicotinic acid methyl ester 8 (49.6 g, >100%) as a black oil.

NMR (CDCl₃) δ: 2.10 (3H, s), 2.28 (3H, s), 3.91 (3H, s), 5.07 (2H, s), 5.20 (2H, s), 7.35-7.41 (5H, m), 8.94 (1H, s).

8) To a solution of the compound 8 (46.8 g, 125 mmol) in methanol (140 ml) was added a 2N aqueous sodium hydroxide solution (376 ml) under ice-cooling, and this was stirred at 50° C. for 40 minutes. To the reaction solution were added diethyl ether and 2N hydrochloric acid under ice-cooling, and precipitated crystals were filtered. Resulting crystals were washed with water and diethyl ether to obtain 5-benzyloxy-4-hydroxy-6-hydroxymethyl-nicotinic acid 9 (23.3 g, 68%) as a colorless crystal.

NMR (DMSO-d₆) δ: 4.49 (2H, s), 5.19 (2H, s), 5.85 (1H, brs), 7.14-7.20 (2H, m), 7.33-7.43 (7H, m), 8.30 (1H, s), 10.73 (1H, t, J=5.8 Hz), 11.96 (1H, brs).

9) To a solution of the compound 9 (131 g, 475 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (219 g, 1140 mmol) and 1-hydroxybenzotriazole (128 g, 950 mmol) in dimethylformamide (1300 ml) was added 4-fluorobenzylamine (109 ml, 950 mmol), and this was stirred at 80° C. for 1.5 hours. After the reaction solution was cooled to room temperature, hydrochloric acid was added, followed by extraction with ethyl acetate. The extract was washed with a 5% aqueous potassium carbonate solution, an aqueous saturated ammonium chloride solution, and an aqueous saturated sodium chloride solution, and dried with anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain a mixture (175 g) of 10 and 11. the resulting mixture was dissolved in acetic acid (1050 ml) and water (1050 ml), and zinc (31.1 g, 475 mmol) was added, followed by heating to reflux for 1 hour. After the reaction solution was cooled to room temperature, a 10% aqueous potassium carbonate solution was added, followed by extraction with ethyl acetate. The extract was washed with an aqueous saturated ammonium chloride solution, and an aqueous saturated sodium chloride solution, and dried with anhydrous sodium sulfate. After the solvent was distilled off under reduced pressure, this was washed with diethyl ether to obtain 5-benzyloxy-N-(4-fluoro-benzyl)-4-hydroxy-6-hydroxymethyl-nicotinic acid amide 10 (107 g, 59%) as a colorless crystal.

NMR (DMSO-d₆) δ: 4.45 (2H, d, J=4.3 Hz), 4.52 (2H, d, J=5.8 Hz), 5.09 (2H, s), 6.01 (1H, brs), 7.36-7.43 (5H, m), 8.31 (1H, s), 12.63 (1H, brs).

PATENT

SYNTHESIS

EP2602260A1

Example 3

3H IS DOLUTEGRAVIR

Step 1

N,N-dimethylformamide dimethyl acetal (4.9 ml, 36.5 mmol) was added dropwise to compound 3A (5.0 g, 30.4 mmol) under cooling at 0°C. After stirring at 0°C for 1 hour, 100 ml of ethyl acetate was added to the reaction solution, and the organic layer was washed with a 0.5 N aqueous hydrochloric acid solution (50 ml). The aqueous layer was separated, followed by extraction with ethyl acetate (50 ml). The organic layers were combined, washed with a saturated aqueous solution of sodium bicarbonate and saturated saline in this order, and then dried over anhydrous sodium sulfate. The solvent was distilled off, and the obtained residue was purified by silica gel column chromatography (n-hexane-ethyl acetate: 1:1 (v/v) → ethyl acetate) to obtain 4.49 g (yield: 67%) of compound 3B as an oil.

¹H-NMR (CDCl₃)δ:1.32 (3H, t, J = 7.1 Hz), 2.90 (3H, br s), 3.29 (3H, br s), 4.23 (2H, q, J = 7.1 Hz), 4.54 (2H, s), 7.81 (1H, s).

Step 2

Lithium hexamethyldisilazide (1.0 M solution in toluene, 49 ml, 49.0 mmol) was diluted with tetrahydrofuran (44 ml). A tetrahydrofuran (10 ml) solution of compound 3B (4.49 g, 20.4 mmol) was added dropwise thereto under cooling at -78°C, and a tetrahydrofuran (10 ml) solution of ethyl oxalyl chloride (3.35 g, 24.5 mmol) was then added dropwise to the mixture. The mixture was stirred at -78°C for 2 hours and then heated to 0°C. 2 N hydrochloric acid was added to the reaction solution, and the mixture was stirred for 20 minutes, followed by extraction with ethyl acetate (200 ml x 2). The organic layer was washed with a saturated aqueous solution of sodium bicarbonate and saturated saline and then dried over anhydrous sodium sulfate. The solvent was distilled off, and the obtained residue was purified by silica gel column chromatography (n-hexane-ethyl acetate: 7:3 → 5:5 → 0:10 (v/v)) to obtain 1.77 g (yield: 31%) of compound 3C as a white solid.

¹H-NMR (CDCl₃)δ:1.36-1.46 (6H, m), 4.35-4.52 (8H, m), 8.53 (1H, s).

Step 3

Aminoacetaldehyde dimethyl acetal (0.13 ml, 1.20 mmol) was added to an ethanol (6 ml) solution of compound 3C (300 mg, 1.09 mmol) at 0°C, and the mixture was stirred at 0°C for 1.5 hours, then at room temperature for 18 hours, and at 60°C for 4 hours. The solvent in the reaction solution was distilled off under reduced pressure, and the obtained residue was then purified by silica gel column chromatography (n-hexane-ethyl acetate: 5:5 → 0:10 (v/v)) to obtain 252 mg (yield: 64%) of compound 3D as an oil.

¹H-NMR (CDCl₃)δ:1.36-1.47 (6H, m), 3.42 (6H, s), 3.90 (2H, d, J = 5.2 Hz), 4.37 (3H, q, J = 7.2 Hz), 4.50 (2H, q, J = 7.2 Hz), 8.16 (1H, s).

Step 4

62% H₂SO₄ (892 mg, 5.64 mmol) was added to a formic acid (10 ml) solution of compound 3D (1.02 g, 2.82 mmol), and the mixture was stirred at room temperature for 16 hours. The formic acid was distilled off under reduced pressure. To the residue, methylene chloride was added, and the mixture was pH-adjusted to 6.6 by the addition of a saturated aqueous solution of sodium bicarbonate. The methylene chloride layer was separated, while the aqueous layer was subjected to extraction with methylene chloride. The methylene chloride layers were combined and dried over anhydrous sodium sulfate. The solvent was distilled off to obtain 531.8 mg of compound 3E as a yellow oil.

1H-NMR (CDCl3) δ: 1.28-1.49 (6H, m), 4.27-4.56 (4H, m), 4.84 (2H, s), 8.10 (1H, s), 9.72 (1H, s).

Step 5

Methanol (0.20 ml, 5.0 mmol), (R)-3-amino-butan-1-ol (179 mg, 2.0 mmol), and acetic acid (0.096 ml, 1.70 mmol) were added to a toluene (5 ml) solution of compound 3E (531 mg, 1.68 mmol), and the mixture was heated to reflux for 4 hours. The reaction solution was cooled to room temperature, then diluted with chloroform, and then washed with a saturated aqueous solution of sodium bicarbonate. The aqueous layer was subjected to extraction with chloroform. The chloroform layers were combined, washed with saturated saline, and then dried over anhydrous sodium sulfate. The solvent was distilled off, and the obtained residue was purified by silica gel column chromatography (chloroform-methanol: 100:0 → 90:10) to obtain 309.4 mg of compound 3F as a brown oil.

1H-NMR (CDCl3) δ: 1.40 (3H, t, J = 7.1 Hz), 1.40 (3H, d, J = 7.1 Hz), 1.55-1.61 (1H, m), 2.19-2.27 (1H, m), 4.00 (1H, d, J = 1.5 Hz), 4.03 (1H, d, J = 2.5 Hz), 4.10 (1H, dd, J = 13.2, 6.3 Hz), 4.26 (1H, dd, J = 13.2, 3.8 Hz), 4.38 (2H, q, J = 7.1 Hz), 5.00-5.05 (1H, m), 5.31 (1H, dd, J = 6.4, 3.9 Hz), 8.10 (1H, s).

Step 6

Potassium trimethylsilanolate (333 mg, 2.34 mmol) was added to a 1,2-dimethoxyethane (2 ml) solution of compound 3F (159 mg, 0.47 mmol), and the mixture was stirred at room temperature for 7 hours. 1 N hydrochloric acid and saturated saline were added to the reaction solution, followed by extraction with chloroform. The chloroform layers were combined and dried over anhydrous sodium sulfate. The solvent was distilled off to obtain 34.4 mg (yield: 25%) of compound 3G as an orange powder.

1H-NMR (CDCl3) δ: 1.46 (3H, d, J = 3.5 Hz), 1.58-1.65 (1H, m), 2.26-2.30 (1H,m), 4.06-4.10 (2H, m), 4.31 (1H, dd, J = 13.8, 5.6 Hz), 4.48 (1H, dd, J = 13.6, 3.9 Hz), 5.03 (1H, t, J = 6.4 Hz), 5.36 (1H, dd, J = 5.5, 4.0 Hz), 8.44 (1H, s), 12.80 (1H, s), 14.90 (1H, s).

Step 7

Compound 3G (16 mg, 0.054 mmol) and 2,4-difluorobenzylamine (17 mg, 0.12 mmol) were dissolved in N,N-dimethylformamide (1 ml). To the solution, N,N,N’,N’-tetramethyl-O-(7-aza-benzotriazol-1-yl)uronium hexafluorophosphate (HATU) (53 mg, 0.14 mmol) and N-methylmorpholine (0.031 ml, 0.28 mmol) were added, and the mixture was stirred at room temperature for 16 hours. 2,4-difluorobenzylamine (17 mg, 0.12 mmol), HATU (64 mg, 0.17 mmol), and N-methylmorpholine (0.037 ml, 0.34 mmol) were further added thereto, and the mixture was stirred at room temperature for additional 16 hours. 0.5 N hydrochloric acid was added to the reaction solution, followed by extraction with ethyl acetate. The ethyl acetate layers were combined, washed with 0.5 N hydrochloric acid and then with saturated saline, and then dried over anhydrous sodium sulfate. The solvent was distilled off, and the obtained residue was purified by preparative high-performance liquid chromatography to obtain 12.5 mg (yield: 55%) of compound 3H as an orange solid.

DOLUTEGRAVIR

1H-NMR (DMSO-d6) δ: 1.36 (3H, d, J = 6.9 Hz), 1.55-1.60 (1H, m), 2.01-2.05 (1H, m), 3.92-3.94 (1H, m), 4.04 (1H, t, J = 12.6 Hz), 4.38-4.41 (1H, m), 4.57-4.60 (1H, m), 4.81-4.83 (1H, m), 5.46-5.49 (1H, m), 7.08-7.11 (1H, m), 7.25-7.30 (1H, m), 7.41 (1H, dd, J = 15.3, 8.7 Hz), 8.53 (1H, s), 10.38 (1H, s), 12.53 (1H, s).

ISOMERS OF DOLUTEGRAVIR

Reference Example 1

Step 1

Acetic acid (180 mg, 3.00 mmol) was added to a toluene (90 ml) solution of compound A-1 (4.39 g, 9.33 mmol) and (R)-3-aminobutan-1-ol (998 mg, 11.2 mmol), and the mixture was stirred at 50°C for 90 minutes. The reaction solution was allowed to cool to room temperature and then poured to a saturated aqueous solution of sodium bicarbonate. The organic layer was separated, while the aqueous layer was subjected to extraction three times with ethyl acetate. The combined extracts were washed with saturated saline and then dried over sodium sulfate. The solvent was distilled off to obtain 4.29 g of crude product A-2.

Step 2

The crude product A-2 obtained in the preceding step was dissolved in ethanol (40 ml). To the solution, a 2 N aqueous sodium hydroxide solution (20 ml) was added at room temperature, and the mixture was stirred at the same temperature for 2 hours. The reaction solution was neutralized to pH 7 using a 2 N aqueous hydrochloric acid solution. The solvent was directly distilled off. The obtained crude product A-3 was subjected to azeotropy with toluene (100 ml) and used in the next step without being purified.

Step 3

HOBt (1.65 g, 12.2 mmol) and WSC HCl (2.34 g, 12.2 mmol) were added at room temperature to a DMF (100 ml) solution of the crude product A-3 obtained in the preceding step, and the mixture was stirred at the same temperature for 15 hours. Water was added to the reaction solution, followed by extraction three times with ethyl acetate. The combined extracts were washed with water three times and then dried over sodium sulfate. The solvent was distilled off, and the obtained oil was subjected to silica gel column chromatography for purification. Elution was performed first with n-hexane-ethyl acetate (3:7, v/v) and then with only ethyl acetate. The fraction of interest was concentrated, and the obtained oil was then dissolved in ethyl acetate. The solution was crystallized with diisopropyl ether as a poor solvent. The obtained crystals were collected by filtration and dissolved again in ethyl acetate. The solution was recrystallized to obtain 1.84 g of compound A-4.

¹HNMR (CDCl₃) δ: 1.49 (3H, d, J = 6.6 Hz), 1.88-1.96 (1H, m), 2.13-2.26 (1H, m), 3.90-4.17 (4H, m), 4.42-4.47 (1H, m), 4.63 (2H, d, J = 6.0 Hz), 5.12-5.17 (1H, m), 5.17 (1H, d, J = 9.9 Hz), 5.33 (1H, d, J = 9.9 Hz), 6.77-6.87 (2H, m), 7.27-7.42 (4H, m), 7.59-7.62 (2H, m), 8.35 (1H, s), 10.41 (1H, t, J = 5.7 Hz).

Step 4

The compound A-4 was subjected to the hydroxy deprotection reaction described in Step F of the paragraph [0088] to obtain compound A-5.

¹HNMR (DMSO-d₆) δ:1.41 (3H, d, J = 6.3 Hz), 1.85-1.92 (1H, m), 1.50-1.75 (1H, m), 4.02-4.09 (3H, m), 4.28-4.34 (1H, m), 4.53 (2H, d, J = 5.7 Hz), 4.64 (1H, dd, J = 3.9 Hz, 12.6 Hz), 5.45 (1H, dd, J = 3.6 Hz, 9.3 Hz), 7.06 (1H, ddd, J = 2.7 Hz, 8.4 Hz, 8.4 Hz), 7.20-7.28 (1H, m), 7.35-7.42 (1H, m), 8.43 (1H, s),10.37 (1H, t, J = 6.0 Hz),12.37 (1H, brs).

Reference Example 2

Compound A-1 was reacted with (S)-3-aminobutan-1-ol in Step 1. Compound B-5 was obtained in the same way as in Reference Example 1.

• ¹HNMR (DMSO-d₆) δ:1.41 (3H, d, J = 6.3 Hz), 1.85-1.92 (1H, m), 1.50-1.75 (1H, m), 4.02-4.09 (3H, m), 4.28-4.34 (1H, m), 4.53 (2H, d, J = 5.7 Hz), 4.64 (1H, dd, J = 3.9 Hz, 12.6 Hz), 5.45 (1H, dd, J = 3.6 Hz, 9.3 Hz), 7.06 (1H, ddd, J = 2.7 Hz, 8.4 Hz, 8.4 Hz), 7.20-7.28 (1H, m), 7.35-7.42 (1H, m), 8.43 (1H, s),10.37 (1H, t, J = 6.0 Hz),12.37 (1H, brs).

PATENT

W02006116764

ENTRY 68

PATENT

WO 2010068262

PATENT

WO 2010068253

PATENT

WO 2011119566

PATENT

Synthesis

WO 2012018065

Example 3

I was under cooling added dropwise at 0 ℃ (4.9 ml, 36.5 mmol) and N, N-dimethylformamide dimethyl acetal (5.0 g, 30.4 mmol) in the first step compound 3A. After stirring for 1 hour at 0 ℃, ethyl acetate was added to 100ml, the reaction mixture was washed with 0.5N aqueous hydrochloric acid (50 ml). Was extracted with ethyl acetate (50ml) and solution was separated and the aqueous layer. The organic layers were combined, washed successively with saturated aqueous sodium bicarbonate solution and saturated brine, and then dried over anhydrous sodium sulfate. After the solvent was distilled off, silica gel column chromatography and the residue obtained was – and purified by (n-hexane (v / v) → ethyl acetate 1:1) to an oil (67% yield) of Compound 3B 4.49 g I got a thing.
¹ H-NMR (CDCl ₃₎^δ: 1.32 (3H, t, J = 7.1 Hz), 2.90 (3H, br s), 3.29 (3H, br s), 4.23 (2H, q, J = 7.1 Hz), 4.54 (2H, s), 7.81 (1H, s).
Diluted with tetrahydrofuran (44 ml) (1.0M toluene solution, 49 ml, 49.0 mmol) the second step lithium hexamethyldisilazide, under cooling at -78 ℃, compound 3B (4.49 g, 20.4 mmol) in this After dropwise tetrahydrofuran (10 ml) was added dropwise tetrahydrofuran (3.35 g, 24.5 mmol) of ethyl oxalyl chloride and (10 ml) solution. After stirring for 2 hours at -78 ℃, I was warmed to 0 ℃. After washing (200 ml x 2), saturated aqueous sodium bicarbonate solution and the organic layer with saturated brine After stirring for 20 minutes, extracted with ethyl acetate by adding 2N hydrochloric acid, the reaction solution was dried over anhydrous sodium sulfate. After removal of the solvent, silica gel column chromatography and the residue obtained – was purified (n-hexane (v / v) ethyl acetate 7:3 → 5:5 → 0:10), compound 3C 1.77 g (yield I as a white solid 31%).
¹ H-NMR (CDCl ₃₎^{δ :1.36-1} .46 (6H, m), 4.35-4.52 (8H, m), 8.53 (1H, s).
Was added at 0 ℃ (0.13 ml, 1.20 mmol) the aminoacetaldehyde dimethyl acetal ethanol (300 mg, 1.09 mmol) of the third step compound 3C to (6 ml) solution, 1 hour and 30 minutes at 0 ℃, 18 hours at room temperature , then I was stirred for 4 hours at 60 ℃. After the solvent was evaporated under reduced pressure and the reaction mixture by silica gel column chromatography and the residue obtained was – and purified by (n-hexane (v / v) ethyl acetate 5:5 → 0:10), compound 3D 252 mg (yield: I got as an oil 64%) rate.
¹ H-NMR (CDCl ₃₎^{δ :1.36-1} .47 (6H, m), 3.42 (6H, s), 3.90 (2H, d, J = 5.2 Hz), 4.37 (3H, q, J = 7.2 Hz), 4.50 (2H, q, J = 7.2 Hz), 8.16 (1H, s).
Was added (892 mg, 5.64 mmol) and ₂ SO ₄ 62-H% formic acid (1.02 g, 2.82 mmol) in a fourth step the compound for 3D (10 ml) solution was stirred at room temperature for 16 hours. Methylene chloride was added to the residue Shi distilled off under reduced pressure and formic acid was adjusted to pH = 6.6 by addition of saturated aqueous sodium bicarbonate. The solution was separated methylene chloride layer was extracted with methylene chloride and the aqueous layer. I was dried over anhydrous sodium sulfate combined methylene chloride layers. The solvent was then distilled off and was obtained as a yellow oil 531.8 mg compound 3E.
1H-NMR (CDCl3) δ: 1.28-1.49 (6H, m), 4.27-4.56 (4H, m), 4.84 (2H, s), 8.10 (1H, s), 9.72 (1H, s).
Amino – – butane – 1 – ol (179 mg, 2.0 mmol), methanol (0.20 ml, 5.0 mmol), (R) -3 toluene (531 mg, 1.68 mmol) in the fifth step to compound 3E (5 ml) solution was added (0.096 ml, 1.70 mmol) acetic acid was heated under reflux for 4 hours. After dilution with chloroform, cooled to room temperature, the reaction mixture was washed with a saturated aqueous sodium bicarbonate solution, and the aqueous layer was extracted with chloroform. After washing with saturated brine combined chloroform layer was dried over anhydrous sodium sulfate. The solvent was then distilled off, silica gel column chromatography and the residue obtained – and (chloroform methanol 100:0 → 90:10), was obtained as a brown oil 309.4 mg compound 3F.
1H-NMR (CDCl3) δ: 1.40 (3H, t, J = 7.1 Hz), 1.40 (3H, d, J = 7.1 Hz), 1.55-1.61 (1H, m), 2.19-2.27 (1H, m), 4.00 (1H, d, J = 1.5 Hz), 4.03 (1H, d, J = 2.5 Hz), 4.10 (1H, dd, J = 13.2, 6.3 Hz), 4.26 (1H, dd, J = 13.2, 3.8 Hz ), 4.38 (2H, q, J = 7.1 Hz), 5.00-5.05 (1H, m), 5.31 (1H, dd, J = 6.4, 3.9 Hz), 8.10 (1H, s).
1,2 (159 mg, 0.47 mmol) in the sixth step compound 3F – was added (333 mg, 2.34 mmol) and potassium trimethylsilanolate dimethoxyethane (2 ml) solution was stirred for 7 hours at room temperature. Brine was added to the 1N-hydrochloric acid to the reaction mixture, followed by extraction with chloroform. The combined chloroform layer was dried over anhydrous sodium sulfate. The solvent was removed by distillation, and I as an orange powder (25% yield) of compound 3G 34.4 mg.
1H-NMR (CDCl3) δ: 1.46 (3H, d, J = 3.5 Hz), 1.58-1.65 (1H, m), 2.26-2.30 (1H, m), 4.06-4.10 (2H, m), 4.31 (1H , dd, J = 13.8, 5.6 Hz), 4.48 (1H, dd, J = 13.6, 3.9 Hz), 5.03 (1H, t, J = 6.4 Hz), 5.36 (1H, dd, J = 5.5, 4.0 Hz) , 8.44 (1H, s), 12.80 (1H, s), 14.90 (1H, s).
2,4 (16 mg, 0.054 mmol) and the seventh step compound 3G – was dissolved in N, N-dimethylformamide (1 ml) (17 mg, 0.12 mmol) difluorobenzyl amine, N, N, N ‘, N was added (0.031 ml, 0.28 mmol) and N-methylmorpholine uronium hexafluorophosphate (HATU) (53 mg, 0.14 mmol), and ‘- tetramethyl-O-(yl 7 – aza – – benzo triazolopyrimidine -1) I was stirred at room temperature for 16 h. 2,4 – was added (0.037 ml, 0.34 mmol) and N-methylmorpholine (64 mg, 0.17 mmol) and (17 mg, 0.12 mmol), HATU difluorobenzylamine, and the mixture was stirred for 16 hours at room temperature. I was extracted with ethyl acetate addition of 0.5N-hydrochloric acid to the reaction mixture. 0.5N-hydrochloric acid and then was washed with saturated brine, and dried over anhydrous sodium sulfate and combined ethyl acetate layer. The solvent was then distilled off, and purified by preparative high performance liquid chromatography residue was obtained as an orange solid (55% yield) of compound 3H 12.5 mg.
1H-NMR (DMSO-d6) δ: 1.36 (3H, d, J = 6.9 Hz), 1.55-1.60 (1H, m), 2.01-2.05 (1H, m), 3.92-3.94 (1H, m), 4.04 (1H, t, J = 12.6 Hz), 4.38-4.41 (1H, m), 4.57-4.60 (1H, m), 4.81-4.83 (1H, m), 5.46-5.49 (1H, m), 7.08-7.11 (1H, m), 7.25-7.30 (1H, m), 7.41 (1H, dd, J = 15.3, 8.7 Hz), 8.53 (1H, s), 10.38 (1H, s), 12.53 (1H, s)

PAPER

http://pubs.acs.org/doi/abs/10.1021/jm400645w

Carbamoyl Pyridone HIV-1 Integrase Inhibitors 3. A Diastereomeric Approach to Chiral Nonracemic Tricyclic Ring Systems and the Discovery of Dolutegravir (S/GSK1349572) and (S/GSK1265744)

Brian A. Johns*†, Takashi Kawasuji‡, Jason G. Weatherhead†, Teruhiko Taishi‡, David P. Temelkoff†, Hiroshi Yoshida‡, Toshiyuki Akiyama‡, Yoshiyuki Taoda‡, Hitoshi Murai‡, Ryuichi Kiyama‡, Masahiro Fuji‡, Norihiko Tanimoto‡, Jerry Jeffrey†, Scott A. Foster†, Tomokazu Yoshinaga‡, Takahiro Seki‡, Masanori Kobayashi‡, Akihiko Sato‡, Matthew N. Johnson†, Edward P. Garvey†, and Tamio Fujiwara‡

^† GlaxoSmithKline Research & Development, Infectious Diseases Therapeutic Area Unit, Five Moore Drive, Research Triangle Park, North Carolina 27709, United States

^‡ Shionogi Pharmaceutical Research Center, Shionogi & Co., Ltd., 3-1-1 Futaba-cho, Toyonaka-shi, Osaka 561-0825, Japan

J. Med. Chem., 2013, 56 (14), pp 5901–5916

DOI: 10.1021/jm400645w

J. Med. Chem. 2013, 56, 5901-5916.

We report herein the discovery of the human immunodeficiency virus type-1 (HIV-1) integrase inhibitors dolutegravir (S/GSK1349572) (3) and S/GSK1265744 (4). These drugs stem from a series of carbamoyl pyridone analogues designed using a two-metal chelation model of the integrase catalytic active site. Structure–activity studies evolved a tricyclic series of carbamoyl pyridines that demonstrated properties indicative of once-daily dosing and superior potency against resistant viral strains. An inherent hemiaminal ring fusion stereocenter within the tricyclic carbamoyl pyridone scaffold led to a critical substrate controlled diastereoselective synthetic strategy whereby chiral information from small readily available amino alcohols was employed to control relative and absolute stereochemistry of the final drug candidates. Modest to extremely high levels of stereochemical control were observed depending on ring size and position of the stereocenter. This approach resulted in the discovery of 3 and 4, which are currently in clinical development.

(4R,12aS)-N-(2,4-Difluorobenzyl)-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino-
[2,1-b][1,3]oxazine-9-carboxamide (3). 1H NMR (CDCl3) δ 12.45 (s, 1H),10.38 (br s, 1H), 8.30 (s, 1H), 7.40−7.30 (m, 1H), 6.85−6.75 (m, 2H),5.26 (d, J = 5.8, 4.1 Hz, 2H), 5.05−4.95 (m, 1H), 4.64 (d, J = 5.9 Hz,2H), 4.27 (dd, J = 13.4, 4.2 Hz, 1H), 4.12 (dd, J = 13.6, 6.0 Hz, 1H), 4.05(t, J = 2.3 Hz, 1H), 4.02 (d, J = 2.2 Hz, 1H), 2.30−2.19 (m, 1H), 1.56(dd, J = 14.0, 2.0 Hz, 1H), 1.42 (d, J = 7.0 Hz, 3H). ES+ LC/MS: m/zcalcd 419.13; found 420.13 (M + 1)+.
(4R,12aS)-N-(2,4-Difluorobenzyl)-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino-
[2,1-b][1,3]oxazine-9-carboxamide (3) sodium salt.

1H NMR(DMSO-d6) δ 10.70 (t, J = 6.0 Hz, 1H), 7.89 (s, 1 H), 7.40−7.30 (m, 1H), 7.25−7.16 (m, 1H), 7.06−6.98 (m, 1H), 5.22−5.12 (m, 1H), 4.87−4.74 (m, 1H), 4.51 (d, J = 5.4 Hz, 2H), 4.35−4.25 (m, 1 H), 4.16 (dd, J =1.8, 14.1 Hz, 1 H), 4.05−3.90 (m, 1H), 3.86−3.74 (m, 1 H), 2.00−1.72(m, 1 H), 1.44−1.32 (m, 1 H), 1.24 (d, J = 6.9 Hz, 3H).

MORE UPDATES……………………………

Process for preparing integrase inhibitors such as dolutegravir and cabotegravir and their analogs, useful for treating viral infections eg HIV infection. Also claims a process for preparing intermediates of dolutegravir and cabotegravir.

(4R, 12aS)-N-[(2,4-Difluorophenyl)methyl]-3 ,4,6,8, 12, 12a-hexahydro-7-hydroxy-4-methyl-6,8-dioxo-2H-pyrido[1 ‘,2’:4,5]pyrazino[2, 1-b][1 ,3]oxazine-9-carboxamide (Formula A):

Formula A

known by the INN name dolutegravir, is a new efficient antiviral agent from the group of HIV integrase inhibitors which is used in combination with some other antiviral agents for treatment of HIV infections, such as AIDS. The compound, which belongs to condensed polycyclic pyridines and was first disclosed in WO2006/1 16764, is marketed.

Another compound disclosed in WO2006/1 16764 is (3S, 1 1 aR)-N-[(2,4-difluorophenyl)methyl]-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7, 1 1 ,1 1 a-hexahydro[1 ,3]oxazolo[3,2-a]pyrido[1 ,2-d]pyrazine-8-carboxamide (Formula

Formula C

known by the INN name cabotegravir.

The complex structures of dolutegravir and cabotegravir present a synthetic challenge. The first description of the synthesis in WO2006/1 16764 shows a 16-steps synthesis (see Scheme A), which is industrially impractical due to its length and low overall yield.

Scheme A

WO 2010/068253 and WO 2006/1 16764 describe an alternative synthesis. The 1 1 -step synthesis, shown in Scheme B1 and Scheme B2, is based on bromination of the 9-position for further introduction of the carboxylic group. The synthesis relies on the use of expensive palladium catalysts and toxic selenium compounds. Furthermore, some variations of these approaches involve pyrone intermediates in several steps. In some cases pyrones are liquids which can complicate purification, while further reactions form complex mixtures.

doiutegravir

Scheme B2

In further alternative syntheses, acetoacetates were used as starting materials. Such an approach is challenging in terms of introducing the hydroxy group in the 7-position. The variation in Scheme C1 , described in WO2012/018065, starts from 4-benzyloxyacetoacetate. The procedure requires 9 steps, but use expensive reagents like palladium catalysts. Moreover, there is described a possibility of formation a co-crystal between an intermediate and hydroquinone, wherein however the additional step may diminish yields and make the process longer and time consuming.

Scheme C1

The variation in Scheme C2, described in WO2012/018065, starts from 4-chloroacetoacetate. The process is not optimal because of problems in steps which include pyrones and because of problems with conversion of 7-chloro to 7-hydroxy group which includes a disadvantageous use of silanolates with low yield (25%).

Scheme C2

The variation in Scheme C3, described in WO201 1/1 19566, starts from unsubstituted acetoacetate. For the introduction of the 7-hydroxy group, bromination is used and substitution of bromo with hydroxy is performed by a use of silanolates. The substitution of the bromine is achieved in a 43% yield.

Scheme C3

The variation in Scheme C4, described in WO201 1/1 19566, starts from 4-methoxyacetoacetate aiming at preparing dolutegravir or cabotegravir. The process uses lithium bases to affect a difficult to control selective monohydrolysis of a diester.

PATENT

WO 2016113372

Carbotegravir, New Patent, WO 2016113372, Lek Pharmaceutical and Chemical Co DD

LEK PHARMACEUTICALS D.D. [SI/SI]; Verovskova 57 1526 Ljubljana (SI)

MARAS, Nenad; (SI).
SELIC, Lovro; (SI).
CUSAK, Anja; (SI)

ViiV Healthcare is developing cabotegravir (first disclosed in WO2006088173), which in July 2016, was reported to be in phase 2 clinical development.

WO-2016113372

The object of the present invention is to provide short, simple, cost-effective, environmentally friendly and industrially suitable processes for beneficially providing dolutegravir and analogues thereof and cabotegravir and analogues thereof, in particular dolutegravir.

Scheme 1

According to an embodiment of the process of the invention the building block 3-aminobutanol can suitably be substituted with other aminoalcohols to give dolutegravir analogues. For example, using (S)-alaninol gives cabotegravir as the final product. Similarly, using amines other than 2,4-difluorobenzylamine in the amidation step results in the synthesis of other dolutegravir analogues.

According to the another preferred embodiment cabotegravir or a pharmaceutically acceptable salt thereof is prepared by the analogue process, which comprises providing a compound of formula (5c)

5c

converting the compound of formula (5c) to a compound of formula (6c)

6c

by carrying out a chlorination reaction, and converting the compound of formula (6c) to cabotegravir and/or a pharmaceutically acceptable salt thereof.

The compound of formula (5c) can preferably be provided by converting a compound of formula (3) to a compound of formula (4c)

Scheme 2

1. ) EtOCOCI, Et₃N / Me₂CO

2. ) 2,4-difiuorobenzylamine

Scheme 3

Analogous compound of formula 7c is a useful intermediate in the synthesis of cabotegravir. Scheme 3a

Scheme 4

Examples

The following examples are merely illustrative of the present invention and they should not be considered as limiting the scope of the invention in any way. The examples and modifications or other equivalents thereof will become apparent to those versed in the art in the light of the present entire disclosure. Particularly, all Examples related to the preparation of dolutegravir and intermediates thereof can be used by the analogy for the preparation of cabotegravir and intermediates thereof.

Example 1 :

Methyl acetoacetate (1 , 25.22 g) and dimethylformamide dimethyl acetal (DMFDMA, 35 mL) was heated at 50-55°C for 2 h, then methanol (60 mL), aminoacetaldehyde dimethyl acetal (24 mL) and acetic acid (4 mL) was added an the mixture was heated under reflux for one hour, then concentrated. MTBE (100 mL) was added and the mixture was kept at 5 °C overnight to crystallize. Upon filtration 46 g (92%) of product 2 was recovered.

¹H NMR (DMSO-d₆): δ 2.31 (s, 3H), 3.30 (s, 6H), 3.49 (m, 2H), 3.61 (s, 3H), 4.43 (m, 1 H), 8.02 (d, 1 H), 10.8 (bs, 1 H). ¹³C NMR (DMSO-d₆): δ 30.52, 35.48, 50.53, 54.23, 98.99, 102.47, 160.70, 166.92, 197.21 .

Example 2:

Compound 2 (5.00 g) was dissolved in 2-propanol, dimethyl oxalate (7.02 g) was added and heated to 40 °C. Sodium methylate (25% in methanol; 20 mL) was slowly (10 min) added, the mixture was then heated to 50-55 °C and stirred at that temperature for 2-2.5 h. The mixture was cooled to ambient temperature, then sodium hydroxide solution (1 M, 65 mL) was added to the mixture and stirred for another 2 h, followed by addition of concentrated hydrochloric acid (1 1 mL) and stirred for another 2 h. The precipitate was filtered and dried to give 8.08 g (NMR assay 47%; 65% yield) of compound 3.

¹H NMR (DMSO-d₆): δ 2.50 (m, 2H), 3.30 (s. 6H), 4.49 (m, 1 H), 7.06 (s, 1 H); 8.70 (s, 1 H). ¹³C NMR (DMSO-d₆): δ 55.23, 55.37, 102.34, 1 15.47, 120.24, 145.17, 162.71 , 165.22, 178.55.

Example 3:

Compound 2 (158.37 g) was dissolved in methanol (548 mL), followed by the addition of dimethyl oxalate (202.2 g). While keeping the temperature below 30°C, potassium ferf-butoxide (192.1 g) was added and reaction mixture was heated at 50 °C overnight. The suspension was then filtered and the filter cake washed with methanol. The filtrate was concentrated (approximately to 680 mL), then water (680 mL) was added, followed by addition of lithium hydroxide hydrate (143.7 g) while keeping the temperature below 40 °C. The suspension was then stirred at ambient temperature overnight and filtered. To the obtained filtrate, concentrated hydrochloric acid (339 mL) was added while keeping the temperature below 30 °C. The suspension was aged for 2 h and filtered to give 4 as a white powder (95.6 g, NMR assay 100%; 52% yield).

Example 4:

Compound 2 (5.00 g) was dissolved in 2-propanol, dimethyl oxalate (7.02 g) was added and heated to 40 °C. Sodium methylate (25% in methanol; 15 mL) was slowly (10 min) added then the mixture was heated to 50-55 °C and stirred at that temperature for 72 h. The mixture was concentrated and components were separated by flash column chromatography (ethyl acetate/methanol 9:1 to 6:4). Early fractions gave compound 22 upon concentration, late fractions gave compound 23.

Compound 22: ¹H NMR (DMSO-d₆): δ 2.49 (m, 2H), 3.28 (s, 6H), 3.73 (s, 3H), 3.85 (s, 3H), 4.41 (m, 1 H), 4.50 (m, 1 H), 6.65 (s, 1 H), 8.36 (s, 1 H). ¹³C NMR (DMSO-d₆): δ 51.63, 53.36, 54.25, 55.47, 102.71 , 1 18.24, 123.60, 140.81 , 150.21 , 162.44, 164.49, 173.43.

Compound 23: ¹H NMR (DMSO-d₆): δ 2.49 (m, 2H), 3.26 (s, 6H); 3.70 (s, 3H); 4.33 (d, 1 H); 4.60 (m, 1 H), 6.19 (s, 1 H), 8.12 (s, 1 H). ¹³C NMR (DMSO-d₆): δ 50.03, 51.34, 54.59, 54.85, 102.91 , 1 16.04, 1 18.19, 148.32, 152.12, 163.46, 165.24, 174.99

Example 5:

Compound 3 (5.5 g; assay 53%) was suspended in acetonitrile, acetic acid (6 mL) and methanesulfonic acid (2.5 mL) were added followed by the heating of mixture to 70 °C for 4 h. The suspension was filtered and filtrate cooled to ambient temperature. Triethylamine (6.6 mL) and (R)-3-amino-butan-1 -ol (1.24 mL) was added followed by heating the mixture at reflux temperature for 20-24 h. The mixture was filtered, filtrate concentrated and 1 M HCI (100 mL) was added, followed by extraction with dichloromethane (3 x 50 mL). Combined organic fractions were concentrated, 2-propanol was added (10 mL) and suspension was stirred at 70-80 °C for 10 min, left to cool to ambient temperature then filtered to give 2.19 g of compound 4 (73%).

¹H NMR (DMSO-de): δ 1.31 (d, 3H), 1.52 (m, 1 H), 1 .97 (m, 1 H), 3.89 (m, 1 H), 4.01 (m, 1 H), 4.46 (m, 1 H), 4.64 (m, 1 H), 4.78 (m, 1 H), 5.50 (m, 1 H), 7.29 (s, 1 H), 8.88 (s, 1 H), 15.83 (s, 1 H). ¹³C NMR (DMSO-d₆): δ 15.22, 29.14, 45.26, 51.13, 62.09, 76.03, 1 16.31 , 1 18.79, 140.53, 146.79, 155.36, 165.24, 178.75.

Example 6:

Compound 3 (14.55 g; assay 49%) was suspended in acetonitrile (125 mL), acetic acid (15 mL) and methanesulfonic acid (6.25 mL) were added followed by the heating of mixture to 70 °C for 4 h. The suspension was filtered and filtrate cooled to ambient temperature. Triethylamine (16.5 mL) and (S)-2-aminopropanol (2.45 mL) was added followed by heating the mixture at reflux temperature for 24 h. The insoluble product was filtered, washed with 2-propanol (20 mL) and dried to give (3S, 1 1 aR)-3-methyl-5,7-dioxo-2,3,5,7, 1 1 ,1 1 a-hexahydrooxazolo[3,2-a]pyrido[1 ,2-d]pyrazine-8-carboxylic acid (5.2 g, 75%).

¹H NMR (DMSO-d₆): δ 1.31 (d, J = 6.3 Hz, 3H), 3.65 (dd, J = 8.6, 6.8 Hz, 1 H), 4.13 (dd, J = 1 1.7, 10.3 Hz, 1 H), 4.28 (m, 1 H), 4.39 (dd, J = 8.6, 6.8 Hz, 1 H), 4.92 (dd, J = 12.3, 4.2 Hz, 1 H), 5.45 (dd, J = 10.2, 4.1 Hz, 1 H), 7.16 (s, 1 H), 8.84 (s, 1 H), 15.74 (s, 1 H).

Example 7:

Compound 4 (0.63 g) was dissolved in dichloromethane (15 mL), cooled to 5°C, then triethylamine (0.31 mL) was added, followed by ethyl chloroformate (0.26 mL), followed by slow (30 min) addition of 2,4-difluorobenzylamine. The mixture was then stirred at ambient temperature for 24 h. Water (10 mL) was added, organic phase was separated and washed with 1 M HCI (15 mL) and water (15 mL), concentrated and treated with 2-propanol to give the product 5 in a quantitative yield.

¹H NMR (CDCI₃): δ 1.39 (d, 3H), 1.52 (s, 1 H), 2.19 (m, 1 H), 4.00 (m, 2H), 4.16 (m, 1 H), 4.31 (m, 1 H), 4.62 (d, 2H), 5.00 (m, 1 H), 5.27 (m, 1 H), 6.80 (m 2H), 7.33 (m, 2H), 8.49 (s, 1 H), 10.48 (s, 1 H). ¹³C NMR (CDCI₃): 15.50, 29.22, 36.43, 45.19, 51.83, 62.79, 103.71 , 103.91 , 1 1 1 .0, 1 1 1 .18, 120.59, 123.04, 130.40, 137.41 , 144.58, 156.27, 163. 87, 177.83.

Example 8:

To a suspension of 4 (2.84 g, 10 mmol) in a mixture of triethylamine (2.24 mL, 16 mmol) and acetone (50 mL) stirring on an ice bath was added ethyl chloroformate (1 .20 mL, 12 mmol). After stirring for 10 min, 2,4-difluorobenzylamine (1.21 mL, 10 mmol) was added and the mixture left stirring at room temperature for 1 h. The product was isolated by slowly diluting the reaction mixture with water (50 mL), partial concentration, filtration, washing with water (2 50 mL) and drying. There was obtained 5 as a white powder (3.48 g, 86%): mp 181.0-184.7 °C.¹H NMR (DMSO-d₆): δ 1.29 (d, J = 7.0 Hz, 3H), 1 .56 (dd, J = 13.9, 2.0 Hz, 1 H), 1 .93-2.06 (m, 1 H), 3.90 (ddd, J = 1 1.6, 5.0, 2.1 Hz, 1 H), 3.98 (td, J = 12.0, 2.2 Hz, 1 H), 4.45 (dd, J = 13.6, 6.6 Hz, 1 H), 4.72 (dd, J = 13.6, 3.8 Hz, 1 H), 4.74-4.81 (m, 1 H), 5.44 (dd, J = 6.6, 3.8 Hz, 1 H), 8.93 (s, 1 H), 15.14 (s, 1 H). ¹³C NMR (DMSO-d₆): δ 15.78, 29.13, 44.89, 52.88, 61 .63, 75.61 , 1 13.54, 128.49, 136.42, 145.64, 154.62, 164.58, 174.58

Example 9:

To a suspension of 4 (1 1.36 g, 40 mmol) in acetonitrile (80 mL) stirring at room temperature was added TCCA (9.29 g, 38 mmol) and DABCO (0.23 g, 5 mol%). After stirring at room temperature for 1 h, the reaction was quenched with a mixture of DMSO (5.26 mL) and water (1.33 mL). The insoluble cyanuric acid was removed by filtration and the filtrate evaporated under reduced pressure to give viscous oil. This was triturated in methanol (20 mL) to induce crystallization. The product was filtered, washed with cold methanol (10 mL) and dried to give 7 as a yellowish powder (5.13 g, 41 %): mp 191 .3-198.7 °C.

Example 10:

Attempted chlorination of 23: Compound 23 (0.54g) was suspended in acetonitrile (10 mL) and trichlorocyanuric acid (0.44 g) was added and the solution was stirred at ambient temperature overnight. Precipitate was filtered. Only traces of a product corresponding to the compound 26 could be detected in the reaction mixture by LC-MS analysis. Conversion did not improve with time.

Example 11 :

Attempted chlorination of 3: Compound 3 (0.30 g) was suspended in acetonitrile (5 mL) and trichlorocyanuric acid (0.13 g) was added. The suspension was stirred at ambient temperature overnight. Only traces of a product corresponding to the compound 24 could be detected in the reaction mixture by LC-MS analysis.

Example 12:

9 10

Trichloroisocyanuric acid (0.23 g) was added in a single portion to a stirred solution of the diethyl 1 -(2,2-dimethoxyethyl)-4-oxo-1 ,4-dihydropyridine-2,5-dicarboxylate (9, 0.66 g) in dry acetonitrile (4 mL) at room temperature. The resulting suspension was stirred at room temperature for ca. 24 h. The reaction mixture was diluted with dichloromethane and filtrated. The filtrate was then concentrated in vacuo to afford crude oil (0.86 g). Purification by flash chromatography (eluting ethyl acetate/cyclohexane) furnished diethyl 3-chloro-1 -(2,2-dimethoxyethyl)-4-oxo-1 ,4-dihydropyridine-2,5-dicarboxylate, 10 as a yellow semi-solid (0.38 g). ¹H NMR (CDCI₃): δ 1.28 (t, J=7A Hz, 3H), 1 .37 (t, J=7.2 Hz, 3H), 3.35 (s, 6H), 3.89 (d, J=5.0 Hz, 2H), 4.27 (q, J=l A Hz, 2H), 4.43 (q, J=l A Hz, 2H), 4.48 (t, J=4.9 Hz, 1 H), 8.15 (s, 1 H). ¹³C NMR (CDCI₃): δ 13.83, 14.13, 55.82, 57.09, 61.41 , 63.72, 102.52, 1 17.35, 126.90, 140.22, 146.92, 160.67, 164.13, 168.95.

Example 13:

Diethyl 1 -(2,2-dimethoxyethyl)-4-oxo-1 ,4-dihydropyridine-2,5-dicarboxylate (9, 0.64 g) was dissolved in anhydrous acetonitrile (6 mL) and treated sequentially with acetic acid (560 μί) and methanesulfonic acid (40 μί). The resulting mixture was heated to 62 °C and stirred for 4 h and more methanesulfonic acid (40 μΙ_) was added. After additional 2 h, more methanesulfonic acid (80 μΙ_) was added. This was repeated after additional 2 h, when more methanesulfonic acid (80 μΙ_) was added. The reaction mixture was stirred additional 17 h at 62 °C then was treated with a mixture of (R)-3-aminobutanol (0.22 g), triethylamine (0.5 mL) and acetonitrile (0.7 mL). The reaction mixture was stirred additional 22 h at 62 °C and then concentrated in vacuo. The crude material was partitioned between dichloromethane and 1 M HCI solution (15 mL). The combined organic phases were dried (Na₂S0₄), filtered and concentrated in vacuo to afford the crude (4R, 12aS)-ethyl 4-methyl-6,8-dioxo-3,4,6,8, 12,12a-hexahydro-2H-pyrido[1 ‘,2’:4,5]pyrazino[2, 1 -b][1 ,3]oxazine-9-carboxylate (11 ) as a brownish oil (0.61 g).

¹H NMR (CD₃OD): δ 8.44 (s, 1 H), 7.16 (m, 1 H), 5.48 (t, J=4.8 Hz, 1 H), 4.86 (m, 1 H), 4.49 (dd, J=13.6, 4.0 Hz, 1 H), 4.30-4.25 (m, 3H), 4.09 (dt, J=12.1 , 2.3 Hz, 1 H), 3.96 (ddd, J=1 1.7, 5.0, 2.1 Hz, 1 H), 2.18-2.10 (m, 1 H), 1.60-1 .56 (m, 1 H) 1 .39 (d, J=7A Hz, 3H), 1.33 (t, J=7A Hz, 3H). ¹³C NMR (CDCI₃): δ 8.45, 14.08, 15.39, 29.17, 45.04, 45.72, 51 .56, 60.86, 62.61 , 76.33, 1 19.54, 123.72, 136.96, 145.67, 156.26, 163.68, 175.43

Example 14:

¹⁰

Diethyl 3-chloro-1 -(2,2-dimethoxyethyl)-4-oxo-1 ,4-dihydropyridine-2,5-dicarboxylate (10, 1.23 g) was dissolved in 85% formic acid (25 mL) at room temperature. The mixture was warmed to 40 °C and stirred for 23 h. The reaction mixture was concentrated in vacuo, and then partitioned between dichloromethane and aqueous NaHC0₃ solution. The combined organic phases were dried (Na₂S0₄), filtered and concentrated in vacuo to afford brownish oil (0.49 g). The crude oil was dissolved in anhydrous toluene (5 mL) and treated sequentially with (R)-3-aminobutanol (0.19 g), methanol (0.2 mL) and acetic acid (96 μί). The resulting mixture was heated to 90 °C and stirred for 20 h. The reaction mixture was cooled to room temperature and then partitioned between dichloromethane and aqueous NaHC0₃ solution. The combined organic phases were dried (Na₂S0₄), filtered and concentrated in vacuo to afford the crude (4R,12aS)-Ethyl 7-chloro-4-methyl-6,8-dioxo-3,4,6,8,12, 12a-hexahydro-2H-pyrido[1 ‘,2’:4,5] pyrazino [2, 1-b][1 ,3]oxazine-9-carboxylate (12) as a brownish oil (0.24 g).

Example 15:

To a solution of 4 (5.68 g, 20 mmol) in dichloromethane (50 mL) stirring in an ice bath was added triethylamine (5.6 mL, 40 mmol), followed by ethyl chloroformate (2.61 mL, 26 mmol). After 20 min, ethanol (50 mL) was added. The mixture was then left stirring 24 h at room temperature and concentrated under reduced pressure. The residue was triturated in acetone (80 mL). The insoluble salt (triethylamine hydrochloride) was removed by filtration. The filtrate was evaporated under reduced pressure to give 11 as an amorphous solid in a quantitative yield (6.1 g).

Example 16:

To a stirring solution of 11 (0.94 g, 3.0 mmol) in acetonitrile (8 mL) heated at 40 °C was added TCCA in portions during 1 h (0.44 g, 1 .8 mmol). After an additional 1 h, the reaction mixture was diluted with a solution of NaHS0₃ (0.60 g) in water (60 mL), extracted with dichloromethane (50 mL) and the extract evaporated under reduced pressure to give a crude product which was purified by flash chromatography (CH₂CI₂ : MeOH, from 98 : 2 to 80 : 20) to give 12 (0.45 g, 44%).

¹H NMR (CDCI₃): δ 1.37 (t, J = 7.1 Hz, 3H), 1.38 (d, J = 7.0 Hz, 3H), 1 .56 (dq, J = 13.9, 2.2 Hz, 1 H), 2.21 (m, 1 H), 3.99 (d, J = 2.3 Hz, 1 H), 4.00 (t, J = 1.8 Hz, 1 H), 4.10 (dd, J = 13.2, 6.6 Hz, 1 H), 4.37-4.27 (m, 3H), 4.98 (m, 1 H), 5.35 (dd, J = 6.6, 3.8 Hz, 1 H), 8.07 (s, 1 H).

¹³C NMR (CDCI₃): δ 14.20, 16.09, 29.34, 44.87, 53.73, 61.49, 62.29, 76.01 , 1 16.22, 133.1 1 , 134.18, 144.52, 155.48, 163.88, 169.98.

Example 17:

To a mixture of 7 (3.89 g, 12.2 mmol) in methanol (12 mL) was added sodium methylate (22.3 mL, 97.6 mmol). The reaction mixture was stirred for 24 h at 30 °C and then quenched with a slow addition of 3M hydrochloric acid (35 mL) while stirring in an ice bath. The mixture was concentrated under reduced pressure to remove most of the methanol, then extracted with dichloromethane (2 30 mL), the combined extracts washed with water (30 mL) and evaporated under reduced pressure. Methanol (20 mL) was added to the obtained amorphous residue and removed under reduced pressure to yield the solid 8 (3.69 g, 98%).

¹H NMR (CDCI₃): δ 15.04 (s, 1 H), 8.42 (s, 1 H), 5.29 (dd, J=5.6, 3.9 Hz, 1 H), 5.01 -4.96 (m, 1 H), 4.42 (dd, J=13.6, 3.6 Hz, 1 H), 4.25 (dd, J=13.6, 6.0 Hz, 1 H), 4.05 (s, 3H), 4.00-3.97 (m, 2H), 2.21 -2-14 (m, 1 H), 1.53 (dd, J=14.1 , 1.9 Hz, 1 H), 1.36 (d, J=7 Hz, 3H). ¹³C NMR (CDCI₃): δ 176.35, 165.94, 155.03, 153.70, 143.08, 130.90, 1 15.94, 76.05, 62.65, 61.45, 53.86, 44.96, 29.43, 16.06.

Example 18:

To a suspension of 7 (2.55 g, 8.0 mmol) in a mixture of triethylamine (1 .46 mL, 10.4 mmol) and acetone (32 mL) stirring on an ice bath was added ethyl chloroformate (0.88 mL, 8.8 mmol). After stirring for 10 min, 2,4-difluorobenzylamine (1.07 mL, 8.8 mmol) was added and the mixture left stirring at room temperature for 1 h. The product was isolated by slowly diluting the reaction mixture with water (40 mL), filtration, washing with water (2 30 mL) and drying. There was obtained 2.91 g of 6 as a white powder (83%).

¹H NMR (CDCI₃): δ 1.30 (d, J = 7.0 Hz, 3H), 1 .49 (dd, J = 14.0, 2.2 Hz, 1 H), 2.14 (ddd, J = 14.6, 1 1.1 , 6.4 Hz, 1 H), 3.89-3.95 (m, 2H), 4.09-4.15 (m, 1 H), 4.26 (dd, J = 13.4, 3.8 Hz, 1 H), 4.55 (d, J = 5.8 Hz, 2H), 4.89-4.98 (m, 1 H), 5.18 (dd, J = 6.2, 3.8 Hz, 1 H), 6.68-6.79 (m, 2H), 7.23-7.31 (m, 1 H), 8.41 (s, 1 H), 10.24 (t, J = 5.8 Hz, 1 H). ¹³C NMR (CDCI₃): δ 16.09, 26.95, 29.30, 36.79, 45.1 1 , 45.28, 53.86, 62.47, 75.93, 103.87 (t, J = 25.4 Hz), 1 1 1 .21 (dd, J = 21 .0, 3.4 Hz), 1 17.32, 130.58 (dd, J = 9.3, 5.8 Hz), 133.40, 143.54, 155.34, 163.16, 163.25, 163.35, 172.88.

Example 19:

To a suspension of 5 (1 .67 g, 4 mmol) in acetonitrile (20 mL) was added DABCO (23 mg, 5 mol%) and TCCA (0.62 g, 2.52 mmol). The mixture was stirred 18 h at 40 °C protected from light and then quenched with a mixture of DMSO (0.48 mL) and water (0.12 mL). The insoluble cyanuric acid was removed by filtration and washed with acetonitrile (5 mL). The filtrate was evaporated under reduced pressure to give viscous oil that was crystallized from a mixture of methanol (6 mL) and water (3 mL), by slowly cooling the solution from 60 °C to room

temperature. The product 6 was filtered, washed with cold methanol (5 mL) and dried to give an off-white powder (1.07 g, 61 %).

¹H NMR (CDCI₃): δ 1.30 (d, J = 7.0 Hz, 3H), 1 .49 (dd, J = 14.0, 2.2 Hz, 1 H), 2.14 (ddd, J = 14.6, 1 1.1 , 6.4 Hz, 1 H), 3.89-3.95 (m, 2H), 4.09-4.15 (m, 1 H), 4.26 (dd, J = 13.4, 3.8 Hz, 1 H), 4.55 (d, J = 5.8 Hz, 2H), 4.89-4.98 (m, 1 H), 5.18 (dd, J = 6.2, 3.8 Hz, 1 H), 6.68-6.79 (m, 2H), 7.23-7.31 (m, 1 H), 8.41 (s, 1 H), 10.24 (t, J = 5.8 Hz, 1 H). ¹³C NMR (CDCI₃): δ 16.09, 26.95, 29.30, 36.79, 45.1 1 , 45.28, 53.86, 62.47, 75.93, 103.87 (t, J = 25.4 Hz), 1 1 1 .21 (dd, J = 21.0, 3.4 Hz), 1 17.32, 130.58 (dd, J = 9.3, 5.8 Hz), 133.40, 143.54, 155.34, 163.16, 163.25, 163.35, 172.88.

Example 20:

To a suspension of 6 (0.44 g) in anhydrous methanol (1 mL) was added a 25% methanolic solution of sodium methylate (1 .14 mL) and the mixture stirred for 4 h at 40 °C. The reaction was quenched with acetic acid (0.4 mL), diluted with water (8 mL), extracted with 2-methyltetrahydrofuran (12 mL), the extract washed with 1 M NaOH(aq) (8 mL), water (8 mL) and evaporated under reduced pressure. To the oily residue was added methanol (8 mL) and evaporated under reduced pressure to give 27 as a white solid (0.38 g, 88%).

Example 21 :

The suspension of (4R, 12aS)-7-chloro-N-(2,4-difluorobenzyl)-4-methyl-6,8-dioxo-3,4,6,8,12, 12a-hexahydro-2H-pyrido[1 ‘,2’:4,5]pyrazino[2, 1 -b][1 ,3]oxazine-9-carboxamide (6, 0.44 g) and solid sodium hydroxide (0.20 g) in absolute ethanol (2 mL) was stirred at room temperature for 24 h. The reaction was quenched with 2M H₂S0₄ (1 .18 mL) and left stirring for 2 h at room temperature. The reaction mixture was filtered through fitted funnel rinsing with water (2 x 2 mL). The obtained white precipitate (0.38 g) was suspended in THF-water (1 :1 , 4.5 mL) and stirred at room temperature for ca. 2 h. The reaction mixture was filtered through fitted funnel rinsing with water (2 ^χ 1 mL) and dried in vacuo at 40°C to afford pure dolutegravir as a white solid (0.33 g, HPLC purity: 99.38%).

¹H NMR (DMSO-d₆): δ 12.51 (s, 1 H), 10.36 (t, J=5.9 Hz, 1 H), 8.50 (s, 1 H), 7.41-7.36 (m, 1 H), 7.26-7.21 (m, 1 H), 7.07-7.03 (m, 1 H), 5.45 (dd, J=5.4, 4.3 Hz, 1 H), 4.81 -4.76 (m, 1 H), 4.59-4.53 (m, 3H), 4.36 (dd, J=13.8, 5.8 Hz, 1 H), 4.05-4.00 (m, 1 H), 3.91-3.88 (m, 1 H), 2.05-1 .97 (m, 1 H), 1.55-1.52 (m, 1 H), 1 .33 (d, J=7.1 Hz, 3H). ¹³C NMR (DMSO-d₆): δ 170.27, 163.68, 162.29, 161 .78 (dd), 159.82 (dd), 154.61 , 140.64, 130.74 (d), 130.67 (d), 122.37 (d), 1 16.73, 1 15.38, 1 1 1 .33 (d), 103.80 (t), 62.01 , 51 .16, 44.69, 35.74, 29.13, 15.21.

Example 22:

A suspension of dolutegravir (0.31 g) in methanol (4 mL) was cooled to 0 °C.25% Solution of sodium methoxide in methanol was added to the mixture and the resulting suspension was stirred at 0 °C for 2 h, then at room temperature for 23 h. The reaction mixture was then filtered through fitted funnel rinsing with methanol (3 x 10 mL). The white precipitate was dried overnight at room temperature to afford pure dolutegravir sodium as a white solid (0.26 g, HPLC purity: 99.84%).

¹H NMR (DMSO-d₆): δ 10.70 (t, J=5.8, 1H), 7.89 (s, 1H), 7.37-7.30 (m, 1H), 7.23-7.19 (m, 1H), 7.04-7.01 (m, 1H), 5.17 (m, 1H), 4.81 (t, J=6.4Hz, 1H), 4.51 (d, J=5.5Hz, 2H), 4.32-4.29 (m, 1H), 4.16 (dd, J=14.1, 4.8 Hz, 1H), 3.99-3.94 (m, 1H), 3.82-3.80 (m, 1H), 1.89-1.84 (m, 1H), 1.38 (d, J=12.9 Hz, 1H), 1.24 (d, J=7.0Hz, 3H).¹³C NMR (DMSO-d₆): δ 177.93, 167.12, 166.08, 161.59 (dd), 161.13, 159.63 (dd), 134.26, 130.44 (d), 130.38 (d), 122.90 (d), 114.95, 111.23 (d), 108.78, 103.64 (t), 75.59, 61.95, 53.11, 43.01, 35.32, 29.22, 15.30.

Example 23:

The suspension of 6 (0.44 g) and solid sodium hydroxide (0.20 g) in absolute ethanol (2 mL) was stirred at room temperature for 24 h. The reaction was diluted with absolute ethanol (10 mL) and left stirring for ca. 30 min at room temperature. The reaction mixture was filtered through fitted funnel rinsing with absolute ethanol (3 x 10 mL) and dried in vacuo at room temperature to afford dolutegravir sodium as a pale yellow solid (0.43 g, HPLC purity: 98.80%). ¹H NMR (DMSO-d₆): δ 10.70 (t, J = 5.8 Hz, 1H), 7.89 (s, 1H), 7.37-7.30 (m, 1H), 7.23-7.19 (m, 1H), 7.04-7.01 (m, 1H), 5.17 (m, 1H), 4.81 (t, J = 6.4 Hz, 1H), 4.51 (d, J = 5.5 Hz, 2H), 4.32-4.29 (m, 1H), 4.16 (dd, J= 14.1, 4.8 Hz, 1H), 3.99-3.94 (m, 1H), 3.82-3.80 (m, 1H), 1.89-1.84 (m, 1H), 1.38 (d, J = 12.9 Hz, 1H), 1.24 (d, J = 7.0 Hz, 3H).¹³C NMR (DMSO-d₆): δ 177.93, 167.12, 166.08, 161.59 (dd), 161.13, 159.63 (dd), 134.26, 130.44 (d), 130.38 (d), 122.90 (d), 114.95, 111.23 (d), 108.78, 103.64 (t), 75.59, 61.95, 53.11, 43.01, 35.32, 29.22, 15.30.

Example 24:

The suspension of (4R,12aS)-N-(2,4-difluorobenzyl)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12, 12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-6][1,3]oxazine-9-carboxamide (27, 0.43 g) and solid sodium hydroxide (0.20 g) in absolute ethanol (2.5 mL) was stirred at room temperature for ca.24 h. The reaction was diluted with mixture of water/ethanol (5 mL, 1:1) and left stirring for ca. 1.5 h at room temperature. The reaction mixture was filtered through fitted funnel rinsing with mixture of water/ethanol (3 x 5 mL, 1:1) and dried in vacuo at room temperature to afford 15 as a pale yellow solid (0.41 g, HPLC purity: 98.87%).

¹H NMR (DMSO-de): δ 10.70 (t, J = 5.8 Hz, 1H), 7.89 (s, 1H), 7.37-7.30 (m, 1H), 7.23-7.19 (m, 1H), 7.04-7.01 (m, 1H), 5.17 (m, 1H), 4.81 (t, J = 6.4 Hz, 1H), 4.51 (d, J = 5.5 Hz, 2H), 4.32-4.29 (m, 1H), 4.16 (dd, J = 14.1, 4.8 Hz, 1H), 3.99-3.94 (m, 1H), 3.82-3.80 (m, 1H), 1.89-1.84 (m, 1H), 1.38 (d, J = 12.9 Hz, 1H), 1.24 (d, J = 7.0 Hz, 3H).¹³C NMR (DMSO-d₆): δ 177.93, 167.12, 166.08, 161.59 (dd), 161.13, 159.63 (dd), 134.26, 130.44 (d), 130.38 (d), 122.90 (d), 114.95, 111.23 (d), 108.78, 103.64 (t), 75.59, 61.95, 53.11, 43.01, 35.32, 29.22, 15.30.

Example 25:

The suspension of {4R, 12aS)-7-chloro-4-methyl-6,8-dioxo-3,4, 6,8, 12,12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-6][1,3]oxazine-9-carboxylic acid (7, 0.31 g) and solid sodium hydroxide (0.20 g) in absolute ethanol (2.5 mL) was stirred at 50 °C for 3 days. The reaction was quenched with 2M H₂S0₄ (1.2 mL) and left stirring for 7 h at room temperature. The reaction mixture was filtered through fitted funnel rinsing with water (3×5 mL) and ethanol (5 mL) dried in vacuo at 40°C to afford 28 as a pale yellow solid (0.17 g).

¹H NMR (DMSO-d₆): δ 15.37 (s, 1H), 12.76 (s, 1H), 8.66 (s, 1H), 5.51-5.49 (m, 1H), 4.80-4.78 (m, 1H), 4.65 (dd, J=13.8, 3.7 Hz, 1H), 4.43 (dd, J=13.8, 5.9 Hz, 1H), 4.05 (t, J^^.b Hz, 1H), 3.91 (dd, J=11.4, 3.1 Hz, 1H), 2.07-2.00 (m, 1H), 1.56 (d, J=13.8 Hz, 1H), 1.34 (d, J=7.0 Hz, 3H).¹³C NMR (DMSO-de): δ 172.21, 165.39, 161.73, 153.61, 141.11, 118.66, 112.99, 75.95, 62.03, 51.50, 44.90, 29.08, 15.18.

Example 26:

The suspension of (4R,12aS)-N-(2,4-difluorobenzyl)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8, 12, 12a-hexahydro-2H-pyrido[1 ‘,2’:4,5]pyrazino[2, 1 ,3]oxazine-9-carboxamide (27, 0.88 g) and solid sodium hydroxide (0.24 g) in absolute ethanol (20 mL) was stirred at 30 °C for 1.5 h. The reaction was quenched with 2M H₂S0₄ (1 .5 mL) and left stirring for 3 hours at room temperature. The reaction mixture was filtered through fritted funnel and rinsed with water (3 x 2 mL) and ethanol (4 mL), and dried in vacuo at 40 °C to afford O-ethyl dolutegravir (29) as a pale yellow solid (0.25 g). The filtrate was extracted with ethyl acetate (3 x 5 mL). The combined organic layers were dried over MgS0₄, filtered and concentrated, then dried in vacuo at 40 °C to afford more 29 as a pale yellow solid (0.27 g).

¹H NMR (CDCI₃): δ 10.37 (t, J = 5.8 Hz, 1 H), 8.36 (s, 1 H), 7.37-7.32 (m, 1 H), 6.83-6.77 (m, 2H), 5.19 (dd, J = 5.9, 3.8 Hz, 1 H), 5.04-4.98 (m, 1 H), 4.61 (d, J = 6Hz, 2H), 4.26-4.22 (m, 3H), 4.1 1 (dd, J = 13.4, 5.9 Hz, 1 H), 3.97 (t, J = 2.4 Hz, 1 H), 3.96 (d, J = 2.4 Hz, 1 H), 2.21-2.14 (m, 1 H), 1.51 (dq, J = 14.0, 2.3 Hz, 1 H), 1 .47 (t, J = 7.0 Hz, 3H), 1 .35 (d, J = 7.1 Hz, 3H).

¹³C NMR (CDCI₃): δ 174.78, 164.17, 162.49 (dd), 160.51 (dd), 155.72, 154.08, 142.32, 130.60 (dd), 129.33, 121 .51 (dd), 1 18.67, 1 1 1 .23 (dd), 103.78 (t), 76.15, 69.74, 62.58, 53.42, 44.58, 36.50 (d), 29.44, 16.04, 15.64.

Example 27:

The suspension of (4R, 12aS)-7-(benzyloxy)-4-methyl-3,4, 12,12a-tetrahydro-2H-pyrido[1 ‘,2’:4,5]pyrazino[2, 1-b][1 ,3]oxazine-6,8-dione (30, 0.68 g, prepared according to prior art) and solid sodium hydroxide (0.40 g) in absolute ethanol (5 mL) was stirred at 50 °C for 14 h. The reaction was quenched with formic acid (0.35 mL), water (2 mL) was added and mixture was left stirring for additional 1 h at room temperature. The reaction mixture was extracted with ethyl acetate (3 x 5 mL) and the combined organic layers concentrated to afford a crude oil. Purification by flash chromatography (eluting with CH₂CI₂/methanol) afforded 32 as an orange solid (0.26 g, 52 %).

The above procedure if done at room temperature in same time period, affords 31 as orange oil (0.24 g, 43 %).

Compound 32: ¹H NMR (DMSO-d₆): δ 7.64 (d, J = 7.4 Hz, 1 H), 6.20 (d, J = 7.3 Hz, 1 H), 5.40 (dd, J = 5.1 , 4.2 Hz, 1 H), 4.83-4.78 (m, 1 H), 4.35 (dd, J = 13.6, 3.9 Hz, 1 H), 4.13 (dd, J = 13.6, 5.4 Hz, 1 H), 4.05-4.00 (m, 1 H), 3.90-3.85 (m, 1 H), 2.03-1.95 (m, 1 H), 1.52 (dd, J = 13.9, 1 .9 Hz, 1 H), 1.33 (d, J = 7.1 Hz, 3H). ¹³C NMR (DMSO-d₆): δ 170.96, 163.01 , 153.48, 137.96, 1 16.83, 1 13.52, 76.18, 62.05, 50.39, 44.53, 29.21 , 15.28.

Compound 31 : ¹H NMR (DMSO-d₆): δ 7.67 (d, J = 7.4 Hz, 1 H), 6.28 (d, J = 7.4 Hz, 1 H), 5.29 (dd, J = 5.4, 3.8 Hz, 1 H), 4.82-4.75 (m, 1 H), 4.32 (dd, J = 13.6, 3.6 Hz, 1 H), 4.10 (dd, J = 13.5, 5.6 Hz, 1 H), 4.03-3.93 (m, 3H), 3.85 (ddd, J = 1 1 .6, 5.0, 2.2 Hz, 1 H), 1.97-1 .89 (m, 1 H), 1 .48 (dd, J = 13.8, 2.1 Hz, 1 H), 1.27 (d, J = 7.1 Hz, 3H), 1.26 (d, J = 7.0 Hz, 3H). ¹³C NMR (DMSO-d₆): δ 174.38, 156.1 1 , 150.82, 139.48, 1 16.39, 1 13.52, 75.92, 67.31 , 61 .80, 51 .36, 44.22, 29.29, 15.76, 15.36.

Exa

The transformation of 6 to dolutegravir with sodium hydroxide in ethanol was monitored for the interconversion of intermediates. The suspension of 6 (0.44 g) and solid sodium hydroxide (0.20 g) in ethanol (3.33 ml.) was stirred at 22 °C. Samples of the reaction mixture were taken after 3, 8 and 24 h for UPLC analysis. After 24 h, the reaction mixture was quenched with 2 M H₂S0₄ (5 ml_), and left stirring at room temperature. The reaction mixture was filtered through fritted funnel, the product rinsed with water (30 ml.) and dried in vacuo at 50 °C overnight to afford dolutegravir as a white solid (0.27 g, 64 %).

The results of reaction monitoring:

Time UPLC analysis (area%)

Entry

(h) compound 6 compound 29 dolutegravir

1 3 h 37.50 20.63 39.99

2 8 h 0.78 15.46 80.32

3 24h 0.31 8.56 88.21

Example 29:

The effect of added water and reaction temperature was evaluated by monitoring 4 reactions in parallel. To the suspensions of 27 (0.86 g) in MeOH were added solid sodium hydroxide (0.40 g) or aqueous solution of NaOH (5 M, 2 ml.) (see Table below). The reactions were stirred in parallel at 50 °C or 22 °C. Samples were taken in timely intervals for UPLC analysis.

The results of reaction monitoring demethylation of 27 in MeOH:

Example 30:

The effect of added water and reaction temperature was evaluated by monitoring 4 reactions in parallel. To the suspensions of 6 (0.88 g) in EtOH were added solid sodium hydroxide (0.40 g) or aqueous solution of NaOH (5 M, 2 mL) (see Table below). The reactions were stirred in parallel at 50 °C or 22 °C. Samples were taken in timely intervals for UPLC analysis.

The results of reaction monitoring of the transformations of 6 in ethanol with NaOH:

dol. = dolutegravir

Exa

The effect of added water and reaction temperature was evaluated by monitoring 4 reactions in parallel. To the suspensions of 27 (0.88 g) in EtOH were added solid sodium hydroxide (0.40 g) or aqueous solution of NaOH (5 M, 2ml_) (see Table below). The reactions were stirred in parallel at 50 °C or 22 °C. Samples were taken in timely intervals for UPLC analysis.

The results of reaction monitoring of the transformations of 27 in ethanol with NaOH:

dol. = dolutegravir

Example 32:

Compound 3 (30 g, 1 10 mmol; assay 99%) was suspended in acetonitrile (450 mL), acetic acid (73 mL) and methanesulfonic acid (25 mL) were added. The reaction mixture was stirred 4 h at 70 °C. The clear red solution was cooled to 25 °C. Triethylamine (77 mL) and (S)-2-aminopropanol (17 mL) were added and the mixture was stirred at reflux temperature for 20 h. The reaction mixture was cooled to 25 °C and the insoluble product filtered, washed with 1 M HCI(aq) (60 mL), water (3 * 60 mL) and dried to give 4c (19.49 g, 67%): mp = 313-315 °C; ¹H NMR (DMSO-d₆): δ 1.31 (d, J = 6.3 Hz, 3H), 3.65 (dd, J = 8.6, 6.8 Hz, 1 H), 4.13 (dd, J = 1 1.7, 10.3 Hz, 1 H), 4.28 (m, 1 H), 4.39 (dd, J = 8.6, 6.8 Hz, 1 H), 4.92 (dd, J = 12.3, 4.2 Hz, 1 H), 5.45 (dd, J = 10.2, 4.1 Hz, 1 H), 7.16 (s, 1 H), 8.84 (s, 1 H), 15.74 (s, 1 H); ¹³C NMR (DMSO-d₆) 16.5, 51.6, 52.9, 72.4, 81.6, 1 15.8, 1 18.1 , 141.5, 147.6, 153.4, 165.3, 179.0.

PATENT

WO2016016279, NOVEL HYDRATES OF DOLUTEGRAVIR SODIUM

LEK PHARMACEUTICALS D.D. [SI/SI]; Verovskova 57 1526 Ljubljana (SI).
SANDOZ AG [CH/CH]; Lichtstrasse 35 CH-4056 Basel (CH)

HOTTER, Andreas; (AT).
THALER, Andrea; (AT).
LEBAR, Andrija; (SI).
JANKOVIC, Biljana; (SI).
NAVERSNIK, Klemen; (SI).
KLANCAR, Uros; (SI).
ABRAMOVIC, Zrinka; (SI)

The present invention relates to novel hydrates of sodium dolutegravir and their methods of preparation. In addition, the invention relates to a novel crystalline form of sodium dolutegravir, which is a useful intermediate for the preparation of one of the new hydrates. The invention also relates to the use of the new hydrates for the production of pharmaceutical compositions.

Finally, the invention relates to pharmaceutical compositions comprising an effective amount of the novel hydrates, oral dosage forms comprising these pharmaceutical compositions, a process for preparing said oral dosage forms, and the use of such pharmaceutical compositions or dosage forms in the treatment of retroviral infections such as HIV infections -1.

Dolutegravir, chemically designated (4f?, 12aS)-/V-(2,4-difluorobenzyl)-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8, 12, 12a-hexahydro-2H-pyrido[1 ‘,2’:4,5]pyrazino[2, 1- ?][1 ,3]oxazine-9-carboxamide, is a human immunodeficiency virus type 1 (HIV-1 ) integrase strand transfer inhibitor (INSTI) indicated in combination with other a nti retroviral agents for the treatment of HIV-1 infection. The marketed finished dosage form (TIVICAY™) contains dolutegravir as its sodium salt, chemically denominated sodium (4f?,12aS)-9-((2,4-difluorobenzyl)carbamoyl)-4-methyl-6,8-dioxo-3,4,6,8,12, 12a-hexahydro-2H-pyrido[1 ‘,2’:4,5]pyrazino[2, 1- ?][1 ,3]oxazin-7-olate, which is represented by the following general chemical formula (I):

(I)

WO 2010/068253 A1 discloses a monohydrate and an anhydrous form of dolutegravir sodium as well as a crystalline form of the free compound. Processes for the preparation of said forms are also provided in the application.

WO 2013/038407 A1 discloses amorphous dolutegravir sodium and processes for preparing the same.

Hydrates of pharmaceutical drug substances are of particular interest as they provide new opportunities for preparing novel pharmaceutical compositions with improved quality, activity and/or compliance. This is due to the fact that hydrates have different physicochemical properties compared to their anhydrous counterparts such as melting point, density, habitus, chemical and physical stability, hygroscopicity, dissolution rate, solubility, bioavailability etc., which influence the formulation process and also impact the final drug product.

If an anhydrous form is selected, phase changes during the formulation process induced by hydrate formation must be avoided. This can be particularly difficult if for example wet granulation is used with a substance that is able to form hydrates like dolutegravir sodium.

Hence, a stable hydrate of dolutegravir sodium would allow to easily formulate dolutegravir sodium in a controlled manner and subsequently also facilitate storage and packaging.

However, the so far known dolutegravir sodium monohydrate disclosed in WO 2010/068253 A1 shows excessive water uptake when exposed to moisture and on the other hand already dehydrates below 30% relative humidity.

Therefore, there is a need for hydrates of dolutegravir sodium with improved physicochemical properties, e.g. for hydrates which are stable over a broad humidity range, in particular for hydrates absorbing only low amounts of water at elevated humidity and on the other hand preserving their crystal structure also at dry conditions. In addition, there is a need for pharmaceutical compositions comprising these hydrates, and thus also for hydrates that allow for improved formulation of dolutegravir sodium in pharmaceutical compositions.

SUMMARY OF THE INVENTION

The present invention relates to novel hydrates of dolutegravir sodium and to processes for their preparation. Specifically, the present invention provides crystalline forms of dolutegravir sodium of formula (I) according to respective claims 1 , 5 and 6, with preferred embodiments being set forth in sub-claim 2. The present invention also provides processes for their preparation according to respective claims 3, 7 and 8, with preferred process embodiments being set forth in sub-claim 4. The present invention further provides the uses according to claims 9 and 16, and a pharmaceutical composition according to claim 10, and preferred embodiments thereof according to sub-claims 1 1 and 12. The present invention also provides a process for the preparation of the pharmaceutical composition according to claim

13, and preferred embodiments thereof according to sub-claim 14. The pharmaceutical composition for therapeutic use is set forth in claim 15.

The novel hydrates are physically and chemically stable over a broad humidity range, show only low water uptakes when exposed to moisture and are even stable at dry conditions. Therefore, the novel hydrates are especially suitable for the preparation of pharmaceutical compositions, e.g. in terms of time and costs.

In particular, it has been found that crystal Form HxA exhibits improved properties which allow for improved formulation of Form HxA in pharmaceutical compositions.

In addition, the present invention relates to a novel crystalline form of dolutegravir sodium, which, for the first time, allows the preparation of one of the novel hydrates and is therefore a valuable intermediate.

PATENT

1361/CHE/2013

Dolutegravir (I) is chemically known as (4/?,12aS)-N-[(2,4-difluorophenyl)methyl]-3,4,6,8,12,12a-hexahydro-7-hydroxy-4-methyl-6,8-dioxo-2//-pyrido[r,2′:4,5]pyrazino[2,l-b][l,3]oxazine-9-carboxamide. Dolutegravir is a human immunodeficiency virus type 1 (HIV-1) integrase strand transfer inhibitor (INSTI) indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection. Dolutegravir is being marketed under the trade name Tivicay®. US 8,129,385 disclosed Dolutegravir or its pharmaceutically acceptable salts thereof. US ‘385 also discloses a process for the preparation of Dolutegravir (I). The process involves the condensation of 5-benzyloxy-4-hydroxy-6-hydroxymethyl nicotinic acid (II) with 2,4-difluorobenzylamine (III) to produce 5-benzyloxy-N-(2,4-difluorobenzyl)-4-hydroxy-6-hydroxymethyl nicotinic acid amide (IV), which is further under goes oxidation using manganese dioxide (Mn02) to produce 5-benzyloxy-N-(2,4-difluorobenzyl)-6-formyl-4-hydroxy-nicotinic acid amide (V). This amide compound (V) is reacted with sodium chlorite (NaClCh) to produce 3-benzyloxy-5-(2,4-difluorobenzylcarbamoyl)-4- hydroxy-pyridine-2-carboxylic acid (VI), which is further treated with methanol (MeOH) to produce 3-benzyloxy-5-(2,4-difluorobenzyl)-4-hydroxy-pyridine-2-carboxylic acid methyl ester (VII).

The methyl ester compound (VII) is reacted with 3-bromopropene to produce l-allyl-3-benzyloxy-5-(2,4-difluorobenzyl)-4-oxo-l,4-dihydro-pyridine-2- carboxylic acid methyl ester (VIII), which is further reacted with potassium osmate dihydrate (K2OSO4.2H2O) to produce 3-benzyloxy-5-(2,4-difluorobenzylcarbamoyl)-4-oxo-l-(2-oxo-ethyl)-l,4-dihydropyridine-2-carboxylic acid methyl ester (IX). The compound (IX) is reacted with (R)-3-amino-l-butanol (X) to produce benzyloxy Dolutegravir (XI), which is deprotected by treating with TFA to produce Dolutegravir (I). The process is as shown in scheme-I below:

The major disadvantage with the above prior-art process is that it involves large no of steps and tedious work-up procedures to isolate the required product. This results a longer period of time cycle is required to produce Dolutegravir (I), which in turn renders the process more costly and less eco friendly. Further the above processes are low yielding and with less purity. US 8,217,034 discloses variant process for the preparation of Dolutegravir.

This process involves the reaction of methyl l-(2,2-dihydroxyethyl)-4-oxo-3-[(phenylmethyl)oxy]-l,4-dihydro-2-pyridine carboxylate (XII) with (R)-3-amino-l-butanol (X) to produce (4R, 12o5)-4-methyl-7-[(phenylmethyl)oxy]-3,4,12,12a-tetrahydro-2//-pyrido[ 1 \2′,4,5] pyrazino[2,l-b][l,3]oxazine-6,8-dione (XIII), which is further undergoes bromination using NBS to produce (4R,12aS)-9-bromo-4-methyl-7-[(phenylmethyl)oxy]-3,4,12,12a-tetrahydro-2H-pyrido[r,2′:4,5]pyrazino[2,l-b][l,3]oxazine-6,8-dione (XIV). The bromo Compound (XIV) is condensed with 2,4-difluorobenzylamine (III) in the presence of Tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) to produce benzyloxy Dolutegravir (XI), which is hydrogenated in the presence of Pd/C to produce Dolutegravir (I). The process is as shown in Scheme-II below:

The major disadvantage with the above prior art process of preparing Dolutegravir is the use of expensive reagent tetrakis(triphenylphosphine)palladium (Pd(PPh3)4> in coupling step. Use of this reagent on industrial scale is not preferred, which makes the process more expensive. WO 2011/119566 discloses another variant process for the preparation of Dolutegravir.

This process involves the reaction of l-(2,2-dimethoxyethyl)-5-methoxy-6-(methoxycarbonyl)-4-oxo-l,4-dihydropyridine-3-carboxylic acid (XV) with acetic acid in presence of methane sulfonic acid to produce 5-methoxy-6-(methoxycarbonyl)-4-oxo-l-(2-oxoethyl)-l,4-dihydropyridine-3-carboxylic acid (XVI), which is further condensed with (R)-3-amino-l-butanol (X) to produce (4R,12aS)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2//-pyrido[ 1 ‘,2’:4,5]pyrazino[2,1 -b] [ 1,3]-oxazine-9-carboxylic acid (XVII). This acid Compound XVII is acylated with 2,4-difluorobenzylamine (III) in the presence of carbonyldiimidazole (CDI) to produce methoxy Dolutegravir (XVIII), which is demethylated in the presence of lithium bromide (LiBr) to produce Dolutegravir (I).

The process is as shown in Scheme-3 below:

The major disadvantage of the above prior art process of preparing Dolutegravir is the use of expensive and highly moisture sensitive reagent, 1,1-carbonyldiimidazole (CDI), during acylation. Use of this reagent on industrial scale is not preferred due to anhydrous conditions required in the process. However, there is always a need for alternative preparative routes, which for example, involve fewer steps, use reagents that are less expensive and/or easier to handle, consume smaller amounts of reagents, provide a higher yield of product, have smaller and/or more eco-friendly waste products, and/or provide a product of higher purity. Hence, there is a need to develop cost effective and commercially viable process for the preparation of Dolutegravir of formula (I). The present invention is related to a process for the preparation of pure Dolutegravir of formula (I), wherein optically active acid addition salt of (R)-3-amino-l-butanol (X) is directly condensed with 5-methoxy-6-(methoxycarbonyl)-4-oxo-l-(2-oxoethyl)-l,4-dihydropyridine-3-carboxylic acid (XVI) instead of condensing with free base of (R)-3-amino-1-butanol (X). The present invention is also related to a process for the preparation of pure Dolutegravir of formula (I), wherein, inexpensive and easily handling condensing reagents in the condensation of (4R, 12aS)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2//-pyrido[l’,2′:4,5]pyrazino [2,l-b][l,3]oxazine-9-carboxylic acid (XVII) with 2,4-difluorobenzylamine (III).

In another embodiment, 5-methoxy-6-(methoxycarbonyl)-4-oxo-l-(2-oxoethyl)-l,4- dihydropyridine-3-carboxylic acid (XVI) used in the present invention is prepared by reacting 4-methoxyacetoacetate (XIX) with N,N-dimethyl-l,l- bis(methyloxy)methanamine (DMF-DMA) (XX) to produce methyl-2- (dimethylaminomethylene)-4-methoxy-3-oxo-butanoate(methyl-3-(dimethylamino)-2 [(methyloxy)acetyl]-2-propenoate) (XXI), which is reacted with aminoacetaldehyde dimethyl acetal (XXII) to produce methyl-2-(2,2-dimethoxyethylaminomethylene)-4-methoxy-3-oxo-butanoate(methyl-3-{[2,2-bis(methyloxy)ethyl]amino}-2-[(methyloxy) acetyl]-2-propenoate) (XXIII).

The compound (XXIII) is contacted with dimethyl ethanedioate in presence of alkali metal alkoxide to produce dimethyl-1-(2,2-dimethoxyethyl)-3-methoxy-4-oxo-l ,4-dihydropyridine-2,5-dicarboxylate (XXIV), which is selectively hydrolyzed with a base to produce l-[2,2-bis(methyloxy)ethyl]-5-(methyloxy)-6-[(methyloxy)carbonyl]-4-oxo-l ,4-dihydro-3-pyridinecarboxylic acid (XV). The compound (XV) is treated with a catalytic amount of a strong protic acid in the presence of acetic acid in an organic solvent to produce a reaction mixture containing 5- methoxy-6-(methoxycarbonyl)-4-oxo-l-(2-oxoethyl)-l,4-dihydropyridine-3-carboxylic acid (XVI), The process is as shown in Scheme-IV below:

The following examples illustrate the nature of the invention and are provided for illustrative purposes only and should not be construed to limit the scope of the invention.

Example-1:

EXAMPLES: Example-1: Process for the preparation of Dolutegravir

Step-i: Preparation of (/?)-3-amino-l-butanol tartarate salt: D-(+) Tartaric acid (12.7 g, 0.085 mol) was added in to a solution of (i?,5)-3-amino-l-butnaol (7.5 g, 0.084 mol) in methanol (100 ml) at 40 °C. The reaction mixture was stirred for about 1 hour at 35-40 °C and the reaction mass was cooled to 0-5°C and maintained for 30-40 minutes. The obtained solid was filtered and washed with chilled methanol (10 ml) at 0-5 °C. The solid was dried to get (i?)-3-amino-l-butanol tartarate salt (8.0 g, 40%).

Step-ii: Preparation of (4rt,12a£)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[l’,2′;4,5]pyrazino[2,l-b][l,3]oxazine-9-carboxylic acid (XVII): l-[2,2-Bis(methyloxy)ethyl]-5-(methyloxy)-6-[(methyloxy)carbonyl]-4-oxo-l,4-dihydro-3-pyridinecarboxylic acid (XV) (lOOg; 0.3175 moles) was suspended in acetonitrile (800 ml) and heated to 80-82°C. A mixture of acetic acid (95.25 g), methanesulfonic acid (9.14 g; 0.09525 moles) and acetonitrile (200 ml) were added to the slurry at 80-82°C. The reaction mass was continued at 80-82°C to complete the reaction. After completion of the reaction, anhydrous sodium acetate (65 g) and (/?)-3-amino-l-butanol tartrate salt (79.68g; 0.3334 moles) were added at 20-25°C and stirred at 60-65°C to complete the reaction. The reaction mass was concentrated and acidified with IN aqueous hydrochloric acid (750 ml) and extracted with methylene chloride (1500 ml) at ice cold temperature. The organic layer was separated, concentrated, treated with hot methanol (350 ml) for 2 h, filtered, washed with methanol and dried to yield (4R,12aS)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[ 1′ ,2′ :4,5]pyrazino[2,1 -b] [ 1,3]oxazine-9-carboxylic acid (XVII) (72 g; HPLC purity: 99.07%).

Step-iii: Process for the preparation of Dolutegravir (I). Method A: Triethylamine (3.61 g; 0.0357 moles) was added to the suspension of (4R,12aS)-7- methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[ 1′ ,2′ :4,5]pyrazino[2,1 – b][l,3]oxazine-9-carboxylic acid (XVII) (10 g; 0.0325 moles) in methylene chloride (50 ml), and cooled to 10-15°C. Pivaloyl chloride (4.3 g; 0.0357 moles) was added to the reaction mass, and stirred at 10-15°C for 1 h. Thereafter, 2,4-difiuorobenzylamine (5.58 g; 0.0389 moles) was added at 10-15°C and then warmed to 20-25°C to complete the reaction. After completion of the reaction, IN aqueous hydrochloric acid (20 ml) was added, organic layer was separated, washed with 5% w/w aqueous sodium bicarbonate solution (10 ml) followed by 15% w/w aqueous sodium chloride solution (10 ml) and concentrated. To the concentrated mass, acetonitrile (100 ml) and Lithium bromide (5.08 g; 0.0584 moles) were added and heated to 65-70°C for 3 h to complete the reaction. After completion of the reaction, the reaction mass was acidified with 5N aqueous hydrochloric acid (40 ml), concentrated to about 50 ml and DM water was added to crystallize the product at 20-25°C. The slurry was stirred for 2 h, filtered, washed with DM water and dried to yield (4R,12aS)-N-(2,4-difluorobenzyl)-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a,-hexahydro-2H-pyrido[ 1′ ,2′ :4,5]pyrazino[2,1 -b] [ 1,3]oxazine-9-carboxamide (I) (11.5 g, HPLC purity: 99.63%).

Method B: Isobutyl chloroformate (4.65 gm, 0.03404 moles) in methylene chloride (10 ml) was added to the solution of N-methylmorpholine (3.45 gm, 0.03410 moles) and (4R,12aS)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[ 1′ ,2′ :4,5]pyrazino-[2,1 -b][l,3]oxazine-9-carboxy!ic acid (XVII) (10.0 gm, 0.03245 moles) in methylene chloride (60 ml) at -10 to 0°C in about 1 h. 2,4-Difloro benzyl amine (4.88 gm, 0.03409 moles) in methylene chloride (10 ml) was added to the cold reaction mass, and stirred at 20-30°C for completion of reaction. After completion of reaction, the reaction mass was washed with 5%w/w aqueous sodium bicarbonate solution (20 ml), IN hydrochloric acid (20 ml), DM water (20 ml) and concentrated. Acetonitrile (120 ml) and lithium bromide (4.8 gm, 0.05516 moles) were added to the concentrated mass, and stirred at 70-80°C for 3 h to complete the reaction. After completion of reaction, the reaction mass was acidified with 5N aqueous hydrochloric acid (40 ml) and concentrated to about 50 ml. DM Water (100 ml) was added to the concentrated reaction mass and stirred for 2 h at 25-30°C to crystallize the product. The product was filtered, washed with DM Water (50 ml) and dried to yield Dolutegravir (I) (10.7 gm, HPLC purity: 99.60%).

Example-2: Process for the preparation of Dolutegravir (I) (4R, 12aS)-N-(2,4-difluorobenzyl)-7-methoxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a,-hexahydro-2H-pyrido[r,2′:4,5]pyrazino[2,l-b][l,3]oxazine-9-carboxamide (XVIII) (2 g, 0.0046 moles) was suspended in isopropyl alcohol (20 ml) and lithium bromide (0.8 g, 0.00924 moles) was added and stirred at 70-80°C for 15 h to complete the reaction. After completion of reaction the reaction mass was acidified with 5N aqueous hydrochloric acid (5 ml) and concentrated. DM Water (20 ml) was added to the concentrated mass and stirred at 25-30°C to crystallize the product. The product was filtered, washed with DM Water and dried to yield Dolutegravir (I) (1.5 g, HPLC purity: 97.93%).

Dolutegravir

 

 

 

Experimental:

¹H NMR (CDCl₃) δ  12.45 (s, 1H), 10.38 (br s, 1H), 8.30 (s, 1H), 7.40-7.30 (m, 1H), 6.85-6.75 (m, 2H), 5.26 (d, J = 5.8, 4.1 Hz, 2H), 5.05-4.95 (m, 1H), 4.64 (d, J = 5.9 Hz, 2H), 4.27 (dd, J = 13.4, 4.2 Hz, 1H), 4.12 (dd, J = 13.6, 6.0 Hz, 1H), 4.05 (t, J = 2.3 Hz, 1H), 4.02 (d, J = 2.2 Hz, 1H), 2.30-2.19 (m, 1H), 1.56 (dd, J = 14.0, 2.0 Hz, 1H), 1.42 (d, J = 7.0 Hz, 3H).////////////LINK

Dolutegravir sodium

DOLUTEGRAVIR SODIUM; UNII-1Q1V9V5WYQ; Dolutegravir (sodium);  GSK1349572A; GSK 1349572A;  1051375-19-9

Molecular Formula:	C20H18F2N3NaO5
Molecular Weight:	441.360596 g/mol

sodium;(4R,12aS)-9-[(2,4-difluorophenyl)methylcarbamoyl]-4-methyl-6,8-dioxo-3,4,12,12a-tetrahydro-2H-pyrido[5,6]pyrazino[2,6-b][1,3]oxazin-7-olate


Sodium(4R,12aS)-9-{[(2,4-Difluorophenyl)methyl]carbamoyl}-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazol-7-olate (1)

Characterization data of 1:

1H NMR (400 MHz, DMSO-d6) δ 10.6–10.7 (t, J = 6.0 Hz, 1H), 7.8 (s, 1H), 7.3 (dd, J = 8.4 and 7.2 Hz, 1H), 7.1–7.2 (m, 1H), 7.0 (t, J = 8.0 Hz, 1H), 5.1 (bs, 1H), 4.7–4.8 (m, 1H), 4.5 (d, J = 5.6 Hz, 2H), 4.2–4.3 (d, J = 11.2 Hz, 1H), 4.1 (m, 1H), 3.9 (m, 1H), 3.7–3.8 (m, 1H), 1.8 (m, 1H), 1.3 (d, J = 13.2 Hz, 1H), 1.2 (d, J = 6.8 Hz, 3H);

13C NMR (400 MHz, DMSO-d6) δ 177.9, 167.0, 166.0, 161.0, 159.9, 160.0, 162.4, 162.5, 158.6, 158.8, 161.1, 161.2, 134.2, 130.4, 130.5, 122–8, 123.0, 114.8, 111.0, 111.3, 108.6, 103.3, 103.8, 75.5, 61.8, 53.1, 42.9, 35.3, 29.1, 15.3;

 IR (KBr, cm–1): 3165, 3072, 2974, 2941, 2873, 1643, 1539, 1504, 1101;

ESI-MS m/z: 418.17.

//////LINK

References

1. [1] American Medical Association (AMA), STATEMENT ON A NONPROPRIETARY NAME ADOPTED BY THE USAN COUNCIL (Dolutegravir) Accessed 3 December 2011.
2.  FDA approves new drug to treat HIV infection http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm364744.htm Aug. 12, 2013
3. “U.S. FDA approves GlaxoSmithKline’s HIV drug Tivicay”. Reuters. 12 August 2013. Retrieved 13 February 2013.
4. “GSK wins priority status for new HIV drug in U.S”. Reuters. 16 February 2013. Retrieved 18 February 2013.
5. “ViiV Healthcare receives approval for Tivicay™ (dolutegravir) in Canada for the treatment of HIV”. Retrieved 11 November 2013.
6. FDA approves new drug to treat HIV infection http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm364744.htm Aug. 12, 2013
7.  U.S. FDA approves GlaxoSmithKline’s HIV drug Tivicay http://www.reuters.com/article/2013/08/12/us-glaxosmithkline-hivdrug-idUSBRE97B0WU20130812 Mon Aug 12, 2013 6:40pm EDT
8. “Dolutegravir Prescribing Information”. Retrieved 3 January 2014.
9.  Raffi, F; Jaeger, H; Quiros-Roldan, E; Albrecht, H; Belonosova, E; Gatell, JM; Baril, JG; Domingo, P; Brennan, C; Almond, S; Min, S; extended SPRING-2 Study, Group (Nov 2013). “Once-daily dolutegravir versus twice-daily raltegravir in antiretroviral-naive adults with HIV-1 infection (SPRING-2 study): 96 week results from a randomised, double-blind, non-inferiority trial.”. The Lancet infectious diseases13 (11): 927–35. PMID24074642.
10. http://www.natap.org/2013/ICAAC/ICAAC_24.htm
11.  Walmsley, Sharon L.; Antela, Antonio; Clumeck, Nathan; Duiculescu, Dan; Eberhard, Andrea; Gutiérrez, Felix; Hocqueloux, Laurent; Maggiolo, Franco; Sandkovsky, Uriel; Granier, Catherine; Pappa, Keith; Wynne, Brian; Min, Sherene; Nichols, Garrett (7 November 2013). “Dolutegravir plus Abacavir–Lamivudine for the Treatment of HIV-1 Infection”. New England Journal of Medicine369 (19): 1807–1818. doi:10.1056/NEJMoa1215541.
12.  Sax, Paul. “SINGLE Study Underscores Waning of the Efavirenz Era — But Probably Just in the USA – See more at:http://blogs.jwatch.org/hiv-id-observations/index.php/single-study-underscores-waning-of-the-efavirenz-era-but-probably-just-in-the-usa/2013/11/06/#sthash.A39SderN.dpuf”. Retrieved 19 December 2013.
13.  Eron, JJ; Clotet, B; Durant, J; Katlama, C; Kumar, P; Lazzarin, A; Poizot-Martin, I; Richmond, G; Soriano, V; Ait-Khaled, M; Fujiwara, T; Huang, J; Min, S; Vavro, C; Yeo, J; VIKING Study, Group (2013 Mar 1). “Safety and efficacy of dolutegravir in treatment-experienced subjects with raltegravir-resistant HIV type 1 infection: 24-week results of the VIKING Study.”. The Journal of infectious diseases207 (5): 740–8. PMID23225901.

14. WO2010011812A1 *	Jul 23, 2009	Jan 28, 2010	Smithkline Beecham Corporation	Chemical compounds
    WO2010011819A1 *	Jul 23, 2009	Jan 28, 2010	Smithkline Beecham Corporation	Chemical compounds

15. • • [Patent Document 1] International publication No.2006/116764 pamphlet
      • [Patent Document 2] International publication No.2010/011812 pamphlet
      • [Patent Document 3] International publication No.2010/011819 pamphlet
      • [Patent Document 4] International publication No.2010/068262 pamphlet
      • [Patent Document 5] International publication No.2010/067176 pamphlet
      • [Patent Document 6] International publication No.2010/068253 pamphlet
      • [Patent Document 7] US Patent 4769380A
      • [Patent Document 8] International applicationPCT/JP2010/055316

    [NON-PATENT DOCUMENTS]

    • • [Non-Patent Document 1] Journal of Organic Chemistry, 1991, 56(16), 4963-4967
      • [Non-Patent Document 2] Science of Synthesis, 2005, 15, 285-387
      • [Non-Patent Document 3] Journal of Chemical Society Parkin Transaction. 1, 1997, Issue. 2, 163-169

Drug@FDA, NDA204790 Pharmacology Review(s).

Antimicrob. Agents Chemother. 2008, 52, 901-908.

Antimicrob. Agents Chemother. 2011, 55, 4552-4559.

Drug@FDA, NDA204790 Microbiology Review(s).

. Drug@FDA, NDA204790 Pharmacology Review(s).

Japan PMDA.

Drug@FDA, NDA204790 Clinical Pharmacology Biopharmaceutics Review(s).

Dolutegravir

Systematic (IUPAC) name
(4R,12aS)-N-(2,4-difluorobenzyl)-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxamide
Clinical data
Trade names	Tivicay
AHFS/Drugs.com	Multum Consumer Information
MedlinePlus	a613043
License data	EU EMA: Dolutegravir US FDA: Dolutegravir
Pregnancy category	US: B (No risk in non-human studies)
Routes of administration	Oral
Legal status
Legal status	UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	n/a[1]
Protein binding	≥98.9%
Metabolism	UGT1A1 and CYP3A
Biological half-life	~14 hours
Excretion	Feces (53%) and urine (18.9%)
Identifiers
CAS Number	1051375-16-6
ATC code	J05AX12 (WHO)
PubChem	CID 54726191
IUPHAR/BPS	7365
ChemSpider	25051637
UNII	DKO1W9H7M1
ChEMBL	CHEMBL1229211
NIAID ChemDB	538122
Chemical data
Formula	C20H19F2N3O5
Molar mass	419.38 g/mol

///////////GSK 1349572, S-349572, GSK 1349572, GSK-1349572, GSK1349572, Tivicay®, GSK1349572, GSK-1349572, S/GSK 1349572, S/GSK1349572, S/GSK1349572 (GSK1349572), S/GSK1349572, UNII:DKO1W9H7M1, 1051375-16-6, DOLUTEGRAVIR, 1051375-19-9,  ドルテグラビルナトリウム , Soltegravir

C[C@@H]1CCO[C@@H]2N1C(=O)c3c(c(=O)c(cn3C2)C(=O)NCc4ccc(cc4F)F)O

CC1CCOC2N1C(=O)C3=C(C(=O)C(=CN3C2)C(=O)NCC4=C(C=C(C=C4)F)F)[O-].[Na+]

Convert a drowning ocean into your swimming pool

REF https://www.linkedin.com/pulse/convert-drowning-ocean-your-swimming-pool-anthony-melvin-crasto-ph-d?trk=pulse_spock-articles

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Olopatadine hydrochloride is an antihistamine (as well as anticholinergic and mast cell stabilizer), sold as a prescription eye dropmanufactured by Alcon in one of three strengths: 0.7% solution or Pazeo in the US, 0.2% solution or Pataday (also called Patanol Sin some countries), and 0.1% or Patanol (also called Opatanol in some countries). It is used to treat itching associated with allergicconjunctivitis (eye allergies). A decongestant nasal spray formulation is sold as Patanase, which was approved by the FDA on April 15, 2008.^[1] It is also available as an oral tablet in Japan under the tradename Allelock, manufactured by Kyowa Hakko Kogyo.^[2]

It should not be used to treat irritation caused by contact lenses. The usual dose for Patanol is 1 drop in each affected eye 2 times per day, with 6 to 8 hours between doses. Both Pazeo and Pataday are dosed 1 drop in each eye daily.

There is potential for Olopatadine as a treatment modality for steroid rebound (red skin syndrome).^[3]

Olopatadine was developed by Kyowa Hakko Kogyo.^[4]

Side Effects

Some known side effects include headache (7% of occurrence), eye burning and/or stinging (5%), blurred vision, dry eyes, foreign body sensation, hyperemia, keratitis, eyelid edema, pruritus, asthenia, sore throat (pharyngitis), rhinitis, sinusitis, and taste perversion.

Synthesis

Olopatadine synthesis:^[5]

References

External links

• Pataday website
• Patanase website
• Olopatadine Ophthalmic via MedlinePlus

Olopatadine

Systematic (IUPAC) name
{(11Z)-11-[3-(dimethylamino)propylidene]-6,11- dihydrodibenzo[b,e]oxepin-2-yl}acetic acid
Clinical data
Trade names	Patanol and others
AHFS/Drugs.com	Monograph
MedlinePlus	a602025
Pregnancy category	C
Routes of administration	Ophthalmic, intranasal, oral
Pharmacokinetic data
Biological half-life	3 hours
Identifiers
CAS Number	113806-05-6
ATC code	S01GX09 (WHO)R01AC08 (WHO)
PubChem	CID 5281071
DrugBank	DB00768
ChemSpider	4444528
UNII	D27V6190PM
KEGG	D08293
ChEMBL	CHEMBL1189432
Chemical data
Formula	C21H23NO3
Molar mass	337.412 g/mol

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Darolutamide

N-((S)-1-(3-(3-Chloro-4-cyanophenyl)-1H-pyrazol-1-yl)-propan-2-yl)-5-(1-hydroxyethyl)-1H-pyrazole-3-carboxamide

N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)-propan-2-yl)-5-(l-hydroxyethyl)-lH-pyrazole-3-carboxamide

• MF C₁₉H₁₉ClN₆O₂
• MW 398.846

BAY 1841788; ODM-201

• Originator Orion
• Developer Bayer HealthCare; Orion
• Class Antineoplastics
• Mechanism of Action Androgen receptor antagonists
• Phase III Prostate cancer

• Most Recent Events

  • 03 Jun 2016 Bayer and Orion plan the phase III ARASENS trial for Prostate cancer
  • 03 Jun 2016 Bayer and Orion expand the licensing agreement to include joint development of ODM 201 for Metastatic hormone-sensitive prostate cancer (mHSPC)
  • 06 May 2016 Long-term combined adverse events data from the the ARADES (phase I/II) and the ARAFOR (phase I) trials in Prostate cancer presented at the 111^th Annual Meeting of the American Urological Association (AUA -2016)

Darolutamide (INN) (developmental code names ODM-201, BAY-1841788) is a non-steroidal antiandrogen, specifically, a full and high-affinity antagonist of the androgen receptor (AR), that is under development by Orion and Bayer HealthCare[1] for the treatment of advanced, castration-resistant prostate cancer (CRPC).^[2][3]

Orion and licensee Bayer are co-developing darolutamide, an androgen receptor antagonist, for treating castration-resistant prostate cancer and metastatic hormone-sensitive prostate cancer. In August 2016, darolutamide was reported to be in phase 3 clinical development. The drug appears to be first disclosed in WO2011051540, claiming novel heterocyclic derivatives as tissue-selective androgen receptor modulators, useful for the treatment of prostate cancer.

Mode of action

Relative to enzalutamide (MDV3100 or Xtandi) and apalutamide (ARN-509), two other recent non-steroidal antiandrogens, darolutamide shows some advantages.^[3] Darolutamide appears to negligibly cross the blood-brain-barrier.^[3] This is beneficial due to the reduced risk of seizures and other central side effects from off-target GABA_A receptor inhibition that tends to occur in non-steroidal antiandrogens that are structurally similar to enzalutamide.^[3] Moreover, in accordance with its lack of central penetration, darolutamide does not seem to increase testosterone levels in mice or humans, unlike other non-steroidal antiandrogens.^[3] Another advantage is that darolutamide has been found to block the activity of all tested/well-known mutant ARs in prostate cancer, including the recently-identified clinically-relevant F876L mutation that produces resistance to enzalutamide and apalutamide.^[3] Finally, darolutamide shows higher affinity and inhibitory efficacy at the AR (K_i = 11 nM relative to 86 nM for enzalutamide and 93 nM for apalutamide; IC₅₀ = 26 nM relative to 219 nM for enzalutamide and 200 nM for apalutamide) and greater potency/efficaciousness in non-clinical models of prostate cancer.^[3]

ORM-15341 is the main active metabolite of darolutamide.^[3] It, similarly, is a full antagonist of the AR, with an affinity (K_i) of 8 nM and an IC₅₀ of 38 nM.^[3]

Clinical trials

Darolutamide has been studied in phase I and phase II clinical trials and has thus far been found to be effective and well-tolerated,^[4] with the most commonly reported side effects including fatigue, nausea, and diarrhea.^[5][6] No seizures have been observed.^[6][7] As of July 2015, darolutamide is in phase III trials for CRPC.^[3]

WHIPPANY, N.J., Sept. 16, 2014 /PRNewswire/ — Bayer HealthCare and Orion Corporation, a pharmaceutical company based in Espoo, Finland, have begun to enroll patients in a Phase III trial with ODM-201, an investigational oral androgen receptor inhibitor in clinical development. The study, called ARAMIS, evaluates ODM-201 in men with castration-resistant prostate cancer who have rising Prostate Specific Antigen (PSA) levels and no detectable metastases. The trial is designed to determine the effects of the treatment on metastasis-free survival (MFS).

“The field of treatment options for prostate cancer patients is evolving rapidly.  However, once prostate cancer becomes resistant to conventional anti-hormonal therapy, many patients will eventually develop metastatic disease,” said Dr. Joerg Moeller, Member of the Bayer HealthCare Executive Committee and Head of Global Development. “The initiation of a Phase III clinical trial for ODM-201 marks the starting point for a potential new treatment option for patients whose cancer has not yet spread.  This is an important milestone for Bayer in our ongoing effort to meet the unmet needs of men affected by prostate cancer.”

Earlier this year, Bayer and Orion entered into a global agreement under which the companies will jointly develop ODM-201, with Bayer contributing a major share of the costs of future development. Bayer will commercialize ODM-201 globally, and Orion has the option to co-promote ODM-201 in Europe. Orion will be responsible for the manufacturing of the product.

About the ARAMIS Study
The ARAMIS trial is a randomized, Phase III, multicenter, double-blind, placebo-controlled trial evaluating the safety and efficacy of oral ODM-201 in patients with non-metastatic CRPC who are at high risk for developing metastatic disease. About 1,500 patients are planned to be randomized in a 2:1 ratio to receive 600 mg of ODM-201 twice a day or matching placebo. Randomisation will be stratified by PSA doubling time (PSADT less than or equal to 6 months vs. > 6 months) and use of osteoclast-targeted therapy (yes vs. no).

The primary endpoint of this study is metastasis-free survival (MFS), defined as time between randomization and evidence of metastasis or death from any cause. The secondary objectives of this study are overall survival (OS), time to first symptomatic skeletal event (SSE), time to initiation of first cytotoxic chemotherapy, time to pain progression, and characterization of the safety and tolerability of ODM-201.

About ODM-201
ODM-201 is an investigational androgen receptor (AR) inhibitor that is thought to block the growth of prostate cancer cells. ODM-201 binds to the AR and inhibits receptor function by blocking its cellular function.

About Oncology at Bayer
Bayer is committed to science for a better life by advancing a portfolio of innovative treatments. The oncology franchise at Bayer now includes three oncology products and several other compounds in various stages of clinical development. Together, these products reflect the company’s approach to research, which prioritizes targets and pathways with the potential to impact the way that cancer is treated.

About Bayer HealthCare Pharmaceuticals Inc.
Bayer HealthCare Pharmaceuticals Inc. is the U.S.-based pharmaceuticals business of Bayer HealthCare LLC, a subsidiary of Bayer AG. Bayer HealthCare is one of the world’s leading, innovative companies in the healthcare and medical products industry, and combines the activities of the Animal Health, Consumer Care, Medical Care, and Pharmaceuticals divisions. As a specialty pharmaceutical company, Bayer HealthCare provides products for General Medicine, Hematology, Neurology, Oncology and Women’s Healthcare. The company’s aim is to discover and manufacture products that will improve human health worldwide by diagnosing, preventing and treating diseases.

Bayer® and the Bayer Cross® are registered trademarks of Bayer.

SYNTHESIS

PATENT

US 2015203479

http://www.google.com/patents/WO2011051540A1?cl=en

PATENT

WO 2012143599

http://www.google.com/patents/US20140094474?cl=de

PATENTS

WO2011051540

https://www.google.com/patents/WO2011051540A1?cl=en

PATENT

IN 2011KO00570

PATENT

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2016120530&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCTDescription

WO-2016120530

Compound of (I) (5 g) was dissolved in an acetonitrile and distilled water. The reaction mixture was heated at 75 °C and then slowly cooled down at RT and stirred at RT for 3 days. The solid obtained was filtered, washed twice with the acetonitrile: water and dried under vacuum at 40 °C and 60 °C to yield crystalline form of (I) (4.42 g) with 88% of yield (example 1, page 10).

Compound (I) can be synthetized using the procedures described in WO

201 1/051540.

Pure diastereomers (la) and (lb) can be suitably synthetized, for example, using ketoreductase enzymes (KREDs) for both S- and R-selective reduction of compound 1 to compound 2 as shown in Scheme 1, wherein R is H or Ci_₆ alkyl.

Scheme 1.

For example, Codexis KRED-130 and KRED -NADH-110 enzymes are useful for obtaining excellent stereoselectivity, even stereospecificity. In Scheme 1 the starting material 1 is preferably an ester (R= Ci_6 alkyl), for example ethyl ester (R=ethyl), such as to facilitate extraction of the product into the organic phase as the compound where R=H has a tendency to remain in the water phase. Intermediate 2 can be protected, preferably with silyl derivatives such as tert-butyldiphenylsilyl, in order to avoid esterification in amidation step. In the case of R=Ci_6 alkyl, ester hydrolysis is typically performed before amidation step, preferably in the presence of LiOH, NaOH or KOH. Amidation from compound 3 to compound 5_is suitably carried out using EDCI HBTU, DIPEA system but using other typical amidation methods is also possible. Deprotection of 5 give pure diastereomers (la) and (lb).

Pyrazole ring without NH substitution is known tautomerizable functionality and is described here only as single tautomer but every intermediate and end product here can exist in both tautomeric forms at the same time.

The stereochemistry of the compounds can be confirmed by using optically pure starting materials with known absolute configuration as demonstrated in Scheme 2, wherein R=H or Ci_6 alkyl, preferably alkyl, for example ethyl. The end products of Scheme 2 are typically obtained as a mixture of tautomers at +300K 1H-NMR analyses in DMSO.

Scheme 2. Synthesis pathway to stereoisomers by using starting materials with known absolute configuration

The crystalline forms I, Γ and Γ ‘ of compounds (I), (la) and (lb), respectively, can be prepared, for example, by dissolving the compound in question in an

acetonitrile: water mixture having volume ratio from about 85: 15 to about 99: 1, such as from about 90: 10 to about 98:2, for example about 95:5, under heating and slowly cooling the solution until the crystalline form precipitates from the solution. The concentration of the compound in the acetonitrile: water solvent mixture is suitably about 1 kg of the compound in 5-25 liters of acetonitrile: water solvent mixture, for example 1 kg of the compound in 10-20 liters of acetonitrile: water solvent mixture. The compound is suitably dissolved in the acetonitrile: water solvent mixture by heating the solution, for example near to the reflux temperature, for example to about 60-80 °C, for example to about 75 °C, under stirring and filtering if necessary. The solution is suitably then cooled to about 0-50 °C, for example to about 5-35 °C, for example to about RT, over about 5 to about 24 hours, for example over about 6 to 12 hours, and stirred at this temperature for about 3 to 72 hours, for example for about 5 to 12 hours. The obtained crystalline product can then be filtered, washed, and dried. The drying is suitably carried out in vacuum at about 40 to 60 °C, for example at 55 °C, for about 1 to 24 hours, such as for about 2 to 12 hours, for example 2 to 6 hours.

The crystalline forms I, Γ and I” of compounds (I), (la) and (lb), respectively, are useful as medicaments and can be formulated into pharmaceutical dosage forms, such as tablets and capsules for oral administration, by mixing with pharmaceutical excipients known in the art.

The disclosure is further illustrated by the following examples.

Example 1. Crystallization of N-((S)- 1 -(3 -(3 -chloro-4-cyanophenyl)- 1 H-pyrazol- 1 -yl)-propan-2-yl)-5 -( 1 -hydroxyethyl)- 1 H-pyrazole-3 -carboxamide (I)

N-((iS)- 1 -(3 -(3 -chloro-4-cyanophenyl)- 1 H-pyrazol- 1 -yl)-propan-2-yl)-5 -( 1 -hydroxyethyl)-! H-pyrazole-3 -carboxamide (I) (5 g), 71.25 ml of acetonitrile, and 3.75 ml of distilled water were charged to a flask, and the mixture was heated up to 75 °C. The mixture was slowly cooled down to RT and stirred at RT for 3 days. The solid obtained was filtered and washed twice with acetonitrile: water (9.5 ml:0.5 ml). The product was dried under vacuum at 40 °C and finally at 60°C to obtain 4.42 g of crystalline title compound (yield of 88 %) which was used in X-ray diffraction study.

Example 3. Synthesis of N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)-propan-2-yl)-5-((S)- 1 -hy droxy ethyl)- lH-pyrazole-3-carboxamide (la)

a) Ethyl-5 -((S) 1 -hydroxy ethyl)- 1 H-pyrazole-3 -carboxylate

HO

MgS0₄ x7H₂0 (341 mg), NADP monosodium salt (596 mg), D(+)-glucose (9.26 g) and optimized enzyme CDX-901 lyophilized powder (142 mg) were added to 0.2 mM of KH₂P0₄ buffer (pH 7.0, 709 ml) to prepare solution I. To this solution I was added solution II which contained ethyl-5 -acetyl- 1 H-pyrazole-3 -carboxylate (8.509 g; 46.70 mmol), EtOH (28 ml) and K ED-130 (NADPH ketoreductase, 474 mg). The mixture was agitated at 30-32°C for 5.5 h (monitoring by HPLC) and allowed to cool to RT. The mixture was evaporated to smaller volume and the residue was agitated with diatomaceous earth and filtered. The mother liquid was extracted with 3×210 ml of EtOAc and dried. The solution was filtered through silica (83 g) and evaporated to dryness to give 7.40 g of the title compound. The optical purity was 100 % ee.

b) Ethyl 5-((S)-l -((tert-butyldiphenylsilyl)oxy)ethyl)- 1 H-pyrazole-3 -carboxylate

Diphenyl-tert-butyl chlorosilane (7.48 g, 27.21 mmol) was added in 26 ml of DMF to a mixture of compound of Example 3(a) (5.00 g, 27.15 mmol) and imidazole (2.81 g, 41.27 mmol) in DMF (50 ml) at RT. The mixture was stirred at RT for 24 h.

Saturated aqueous NaHC0₃ (56 ml) and water (56 ml) were added and the mixture was stirred at RT for 20 min. The mixture was extracted with 2×100 ml of EtOAc. Combined organic phases were washed with water (1×100 ml, 1×50 ml), dried (Na₂S0₄), filtered and concentrated to give 10.92 g of crude title compound.

c) 5-((S)-l -((tert-Butyldiphenylsilyl)oxy)ethyl)- 1 H-pyrazole-3 -carboxylic acid

2 M NaOH (aq) (38.8 ml; 77.5 mmol) was added to a solution of the compound of Example 3(b) (10.9 g, 25.8 mmol) in 66 ml of THF. The mixture was heated up to reflux temperature. Heating was continued for 2.5 h and THF was removed in vacuum. Water (40 ml) and EtOAc (110 ml) were added. Clear solution was obtained after addition of more water (10 ml). Layers were separated and aqueous phase was extracted with 100 ml of EtOAc. Combined organic phases were dried (Na₂S0₄), filtered and concentrated to give 9.8 g of the title compound.

d) 5-((S)- 1 -((tert-Butyldiphenylsilyl)oxy)ethyl)-N-((S)- 1 -(3-(3-chloro-4-cyano-phenyl)- 1 H-pyrazol- 1 -yl)propan-2-yl)- 1 H-pyrazole-3 -carboxamide

Under nitrogen atmosphere HBTU (0.84 g; 2.22 mmol), EDCIxHCl (3.26 g; 17.02 mmol) and (S)-4-(l-(2-aminopropyl)-lH-pyrazol-3-yl)-2-chlorobenzonitrile (3.86 g; 14.80 mmol) were added to a mixture of crude compound of Example 3(c) (8.68g; purity 77.4 area-%) and DIPEA (2.20 g; 17.02 mmol) in DCM (50 ml). The mixture was stirred at RT for 46 h (6 ml of DCM was added after 20 h). The mixture was washed with 3×20 ml of water, dried (Na₂S0₄), filtered and concentrated to give 13.7 g of crude title compound.

e) N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)propan-2-yl)-5-((S)- 1 -hydroxy ethyl)- 1 H-pyrazole-3 -carboxamide (la)

TBAF hydrate (Bu₄NF x 3H₂0; 2.34 g; 7.40 mmol) in 10 ml of THF was added to the solution of the compound of Example 3(d) (9.43 g; 14.79 mmol) in THF (94 ml) at 0 °C under nitrogen atmosphere. Stirring was continued at RT for 21.5 h and the mixture was concentrated. DCM (94 ml) was added to the residue and the solution was washed with 3×50 ml of water, dried (Na₂S0₄), filtered and concentrated. Crude product was purified by flash chromatography (EtOAc/n-heptane) to give 2.1 g of the title compound. 1H-NMR (400MHz; d6-DMSO; 300K): Major tautomer (-85 %): δ 1.11 (d, 3H), 1.39 (d, 3H), 4.24-4.40 (m, 2H), 4.40-4.50 (m, 1H), 6.41(s, 1H), 6.93 (d, 1H), 7.77-7.82 (m, 1H), 7.88-8.01 (m, 2H), 8.08 (s, 1H), 8.19 (d, 1H), 13.02 (broad s, 1H). Minor tautomer (-15 %) δ 1.07-1.19 (m, 3H), 1.32-1.41 (m, 3H), 4.24-4.40 (m, 2H), 4.40-4.50 (m, 1H), 6.80 (broad s, 1H), 6.91-6-94 (m, 1H), 7.77-7.82 (m, 1H), 7.88-8.01 (m, 2H), 8.05-8.09 (m, 1H), 8.31 (d, 1H), 13.10 (broad s, 1H).

Example 4. Crystallization of N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)propan-2-yl)-5-((S)- 1 -hy droxy ethyl)- lH-pyrazole-3-carboxamide (la)

N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)propan-2-yl)-5-((S)- 1 -hydroxyethyl)-lH-pyrazole-3-carboxamide (la) (5.00 g; 12.54 mmol) was mixed with 47.5 ml of ACN and 2.5 ml of water. The mixture was heated until compound (la) was fully dissolved. The solution was allowed to cool slowly to RT to form a precipitate. The mixture was then further cooled to 0 °C and kept in this temperature for 30 min. The mixture was filtered and the precipitate was dried under vacuum to obtain 4.50 g of crystalline title compound which was used in the X-ray diffraction study.

Example 6. Synthesis of N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)-propan-2-yl)-5-((R)- 1 -hy droxy ethyl)- lH-pyrazole-3-carboxamide (lb)

a) Ethyl-5 -((R)- 1 -hydroxy ethyl)- 1 H-pyrazole-3 -carboxylate

Potassium dihydrogen phosphate buffer (Solution I) was prepared by dissolving potassium dihydrogen phosphate (11.350 g, 54.89 mmol) to water (333 ml) and adjusting pH of the solution to 7.0 by addition of 5 M solution of NaOH. MgS0₄ x 7 H₂0 (1.650 g), NAD monosodium salt (0.500 g), D(+)-glucose (10.880 g) and optimised enzyme CDX-901 lyophilised powder (0.200 g) were added to Solution I. To this solution (Solution II) were added KRED-NADH- 110 (0.467 g), ethyl-5-acetyl-1 H-pyrazole-3 -carboxylate (10.00 g; 54.89 mmol) and 2-methyltetrahydro-furan (16 ml). The mixture was agitated at 30° C for 11 h and allowed to cool to RT overnight. The pH of the mixture was kept at 7 by addition of 5 M solution of NaOH. The mixture was evaporated to a smaller volume. The evaporation residue was agitated for 10 min with diatomaceous earth (40 g) and activated charcoal (0.54 g), and filtered. Material on the filter was washed with water (40 ml) and the washings were combined with the filtrate. Layers were separated and aqueous phase was extracted with EtOAc (450 ml and 2×270 ml). Combined organic phases were dried over Na₂S0₄, filtered and evaporated to dryness to give 9.85 g of the title compound (100 % ee).

b) Ethyl-5 -((R)- 1 -((tert-butyldiphenylsilyl)oxy)ethyl)- 1 H-pyrazole-3 -carboxylate

Imidazole (5.32 g; 78.08 mmol) was added to a DCM (67 ml) solution of the compound of Example 6(a) (9.85 g; 53.48). The mixture was stirred until all reagent was dissolved and tert-butyldiphenyl chlorosilane (13.21 ml; 50.80 mmol) was added to the mixture. The mixture was stirred for 1.5 h, 70 ml of water was added and stirring was continued for 15 min. Layers were separated and organic phase was washed with 2×70 ml of water and dried over Na₂S0₄, filtered and concentrated to give 22.07 g of crude title compound.

c) 5 -((R)- 1 -((tert-Butyldiphenylsilyl)oxy)ethyl)- 1 H-pyrazole-3 -carboxylic acid

Compound of Example 6(b) (11.3 g; 26.74 mmol; theoretical yield from the previous step) was dissolved in 34 ml of THF and 50 ml of 2 M NaOH (aq.) was added. The mixture was heated under reflux temperature for 70 min. The mixture was extracted with 2×55 ml of EtOAc and combined organic phases were washed with brine, dried over Na₂S0₄, filtered and concentrated. Evaporation residue was triturated in 250 ml of n-heptane, filtered and dried to give 17.58 g of crude title compound.

d) 5-((R)- 1 -((tert-Butyldiphenylsilyl)oxy)ethyl)-N-((S)- 1 -(3-(3-chloro-4-cyano-phenyl)- 1 H-pyrazol- 1 -yl)propan-2-yl)- 1 H-pyrazole-3 -carboxamide

A mixture of the compound of Example 6(c) (11.14 g; 26.75 mmol; theoretical yield from the previous step), 91 ml of DCM, HBTU (1.52 g; 4.01 mmol), EDCIxHCl

(5.90 g; 30.76 mmol), (S)-4-(l-(2-aminopropyl)-lH-pyrazol-3-yl)-2-chlorobenzo-nitrile (6.97 g; 26.75 mmol) and DIPEA (3.98 g; 30.76 mmol) was stirred at RT for 3 h and at 30° C for 22 h. The mixture was washed with 2×90 ml of 0.5 M HC1 and 4×90 ml of water, dried over Na₂S0₄, filtered and concentrated. Crude product was purified by flash column chromatography (n-heptane-EtOAc) to give 16.97 g of title compound.

e) N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)propan-2-yl)-5-((R)- 1 -hydroxy ethyl)- 1 H-pyrazole-3 -carboxamide (lb)

A mixture of the compound of Example 6(d) (6.09 g; 9.56 mmol), 61 ml of THF and TBAF was stirred at 40 °C for 6.5 h. The mixture was concentrated and 61 ml of EtOAc was added to the evaporation residue. Solution was washed with 2×50 ml of 0.5 M HC1 and 4×50 ml of water, dried over Na₂S0₄, filtered and concentrated. Crude product was purified by flash column chromatography (n-heptane-EtOAc) to give 1.71 g of the title compound. 1H-NMR (400MHz; d6-DMSO; 300K): Major tautomer (~85%): 5 1.10 (d, 3H), 1.38 (d, 3H), 4.14-4.57 (m, 2H), 5.42 (d, 1H),

6.39(s, 1H), 6.86-6.98 (m, 1H), 7.74-7.84 (m, 1H), 7.86-8.02 (m, 2H), 8.08 (s, 1H), 8.21 (d, 1H), 13.04 (broad s, 1H). Minor tautomer (-15%) δ 0.95-1.24 (m, 3H), 1.25-1.50 (m, 3H), 4.14-4.57 (m, 2H), 4.60-4.90 (m, 1H), 5.08 (d, 1H), 6.78 (broad s, 1H), 6.86-6.98 (m, 1H), 7.77-7.84 (m, 1H), 7.86-8.02 (m, 2H), 8.02-8.12 (m, 1H), 8.32 (d, 1H), 13.1 1 (broad s, 1H).

Example 7. Crystallization of N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)propan-2-yl)-5-((R)- 1 -hy droxy ethyl)- 1 H-pyrazole-3 -carboxamide (lb)

N-((S)- 1 -(3-(3-chloro-4-cyanophenyl)- lH-pyrazol- 1 -yl)propan-2-yl)-5-((R)- 1 -hydroxyethyl)-l H-pyrazole-3 -carboxamide (lb) (3.7 g; 9.28 mmol) was mixed with 70 ml of ACN and 3.5 ml of water. The mixture was heated to reflux temperature until compound (lb) was fully dissolved. The solution was allowed to cool slowly. The mixture was filtered at 50 °C to obtain 6.3 mg of the precipitate. Mother liquid was cooled to 41 °C and filtered again to obtain 20.7 mg of the precipitate. Obtained mother liquid was then cooled to 36 °C and filtered to obtain 173 mg of the precipitate. The final mother liquid was cooled to RT, stirred overnight, cooled to 0 °C, filtered, washed with cold ACN: water (1 : 1) and dried to obtain 2.71 g of the precipitate. The precipitates were checked for optical purity and the last precipitate of crystalline title compound (optical purity 100 %) was used in the X-ray diffraction study.

Example 9. Synthesis of Ethyl-5 -((S) 1 -hydroxy ethyl)- 1 H-pyrazole-3 -carboxylate

HO

Zinc trifluoromethanesulfonate (0.259 g; 0.713 mmol) and (S)-(-)-3-butyn-2-ol (0.25 g; 3.57 mmol) were added to 0.75 ml (5.35 mmol) of Et₃N under nitrogen

atmosphere. Ethyldiazoacetate (0.45 ml; 4.28 mmol) was added slowly and the

mixture was heated at 100 °C for 2 h. The mixture was cooled to RT and 5 ml of water was added. The mixture was washed with 15 ml of DCM, 5 ml of water was added and phases were separated. Water phase was washed twice with DCM, all organic layers were combined, dried with phase separator filtration and evaporated to dryness to give 0.523 g of crude material. The product was purified by normal phase column chromatography (0-5 % MeOH:DCM) to give 0.165 mg of the title compound. 1H-NMR (400MHz; d6-DMSO; temp +300 K): Tautomer 1 (major 77%): δ 1.28 (t, 3H), 1.39 (d, 3H), 4.20-4.28 (m, 2H), (d, 1H), 4.75-4.85 (m, 1H) 5.43 (broad d, 1H), 6.54 (broad s, 1H), 13.28 (broad s, 1H). Tautomer 2 (minor 23%): δ 1.28 (t, 3H), 1.39 (d, 3H), 4.20-4.28 (m, 2H), 4.66-4.85 (m, 1H), 5.04-5.15 (broad s, 1H), 6.71 (broad s, 1H), 13.60 (broad s, 1H).

Exam le 10. Ethyl-5 -((R)- 1 -hydroxy ethyl)- 1 H-pyrazole-3 -carboxylate

Zinc trifluoromethanesulfonate (1.037 g; 2.85 mmol) and (R)-(+)-3-butyn-2-ol (1.00 g; 14.27 mmol) were added to 2.98 ml (21.40 mmol) of Et₃N under nitrogen atmosphere. Ethyldiazoacetate (1.80 ml; 21.40 mmol) was added slowly and then refluxed for 3 h. The mixture was cooled to RT and 45 ml of water was added. The mixture was extracted with 3×50 ml of DCM, organic layers were combined, dried with phase separator filtration and evaporated to dryness to give 2.503 g of crude material which was purified by normal phase column chromatography (0-10 % MeOH:DCM) to give 0.67 lmg of the title compound. 1H-NMR (400MHz; d6-DMSO; temp +300 K): Tautomer 1 (major 78%): δ 1.28 (t, 3H), 1.39 (d, 3H), 4.18-4.35 (m, 2H), (d, 1H), 4.75-4.85 (m, 1H) 5.42 (broad d, 1H), 6.54 (s, 1H), 13.29 (broad s, 1H). Tautomer 2 (minor 22%): δ 1.28 (t, 3H), 1.39 (d, 3H), 4.18-4.35 (m, 2H), 4.66-4.85 (m, 1H), 5.09 (broad s, 1H), 6.71 (broad s, 1H), 13.61 (broad s, 1H).

References

External links

• Darolutamide (ODM-201) – AdisInsight

Fenner A. Prostate cancer: ODM-201 tablets complete phase I. Nat Rev Urol. 2015 Dec;12(12):654. doi: 10.1038/nrurol.2015.268. Epub 2015 Nov 3. PubMed PMID: 26526759.

2: Massard C, Penttinen HM, Vjaters E, Bono P, Lietuvietis V, Tammela TL, Vuorela A, Nykänen P, Pohjanjousi P, Snapir A, Fizazi K. Pharmacokinetics, Antitumor Activity, and Safety of ODM-201 in Patients with Chemotherapy-naive Metastatic Castration-resistant Prostate Cancer: An Open-label Phase 1 Study. Eur Urol. 2015 Oct 10. pii: S0302-2838(15)00964-1. doi: 10.1016/j.eururo.2015.09.046. [Epub ahead of print] PubMed PMID: 26463318.

3: Fizazi K, Albiges L, Loriot Y, Massard C. ODM-201: a new-generation androgen receptor inhibitor in castration-resistant prostate cancer. Expert Rev Anticancer Ther. 2015;15(9):1007-17. doi: 10.1586/14737140.2015.1081566. PubMed PMID: 26313416; PubMed Central PMCID: PMC4673554.

4: Bambury RM, Rathkopf DE. Novel and next-generation androgen receptor-directed therapies for prostate cancer: Beyond abiraterone and enzalutamide. Urol Oncol. 2015 Jul 7. pii: S1078-1439(15)00269-0. doi: 10.1016/j.urolonc.2015.05.025. [Epub ahead of print] Review. PubMed PMID: 26162486.

5: Moilanen AM, Riikonen R, Oksala R, Ravanti L, Aho E, Wohlfahrt G, Nykänen PS, Törmäkangas OP, Palvimo JJ, Kallio PJ. Discovery of ODM-201, a new-generation androgen receptor inhibitor targeting resistance mechanisms to androgen signaling-directed prostate cancer therapies. Sci Rep. 2015 Jul 3;5:12007. doi: 10.1038/srep12007. PubMed PMID: 26137992; PubMed Central PMCID: PMC4490394.

6: Thibault C, Massard C. [New therapies in metastatic castration resistant prostate cancer]. Bull Cancer. 2015 Jun;102(6):501-8. doi: 10.1016/j.bulcan.2015.04.016. Epub 2015 May 26. Review. French. PubMed PMID: 26022286.

7: Bjartell A. Re: activity and safety of ODM-201 in patients with progressive metastatic castration-resistant prostate cancer (ARADES): an open-label phase 1 dose-escalation and randomised phase 2 dose expansion trial. Eur Urol. 2015 Feb;67(2):348-9. doi: 10.1016/j.eururo.2014.11.019. PubMed PMID: 25760250.

8: De Maeseneer DJ, Van Praet C, Lumen N, Rottey S. Battling resistance mechanisms in antihormonal prostate cancer treatment: Novel agents and combinations. Urol Oncol. 2015 Jul;33(7):310-21. doi: 10.1016/j.urolonc.2015.01.008. Epub 2015 Feb 21. Review. PubMed PMID: 25708954.

9: Boegemann M, Schrader AJ, Krabbe LM, Herrmann E. Present, Emerging and Possible Future Biomarkers in Castration Resistant Prostate Cancer (CRPC). Curr Cancer Drug Targets. 2015;15(3):243-55. PubMed PMID: 25654638.

10: ODM-201 is safe and active in metastatic castration-resistant prostate cancer. Cancer Discov. 2014 Sep;4(9):OF10. doi: 10.1158/2159-8290.CD-RW2014-150. Epub 2014 Jul 9. PubMed PMID: 25185192.

11: Fizazi K, Massard C, Bono P, Jones R, Kataja V, James N, Garcia JA, Protheroe A, Tammela TL, Elliott T, Mattila L, Aspegren J, Vuorela A, Langmuir P, Mustonen M; ARADES study group. Activity and safety of ODM-201 in patients with progressive metastatic castration-resistant prostate cancer (ARADES): an open-label phase 1 dose-escalation and randomised phase 2 dose expansion trial. Lancet Oncol. 2014 Aug;15(9):975-85. doi: 10.1016/S1470-2045(14)70240-2. Epub 2014 Jun 25. PubMed PMID: 24974051.

12: Agarwal N, Di Lorenzo G, Sonpavde G, Bellmunt J. New agents for prostate cancer. Ann Oncol. 2014 Sep;25(9):1700-9. doi: 10.1093/annonc/mdu038. Epub 2014 Mar 20. Review. PubMed PMID: 24658665.

13: Pinto Á. Beyond abiraterone: new hormonal therapies for metastatic castration-resistant prostate cancer. Cancer Biol Ther. 2014 Feb;15(2):149-55. doi: 10.4161/cbt.26724. Epub 2013 Nov 1. Review. PubMed PMID: 24100689; PubMed Central PMCID: PMC3928129.

14: Yin L, Hu Q, Hartmann RW. Recent progress in pharmaceutical therapies for castration-resistant prostate cancer. Int J Mol Sci. 2013 Jul 4;14(7):13958-78. doi: 10.3390/ijms140713958. Review. PubMed PMID: 23880851; PubMed Central PMCID: PMC3742227.

15: Leibowitz-Amit R, Joshua AM. Targeting the androgen receptor in the management of castration-resistant prostate cancer: rationale, progress, and future directions. Curr Oncol. 2012 Dec;19(Suppl 3):S22-31. doi: 10.3747/co.19.1281. PubMed PMID: 23355790; PubMed Central PMCID: PMC3553559.

Darolutamide

Systematic (IUPAC) name
N-((S)-1-(3-(3-chloro-4-cyanophenyl)-1H-pyrazol-1-yl)propan-2-yl)-5-(1-hydroxyethyl)-1H-pyrazole-3-carboxamide[1]
Identifiers
ChemSpider	38772320
UNII	X05U0N2RCO
Chemical data
Formula	C19H19ClN6O2
Molar mass	398.85 g·mol−1

//////////// Bayer HealthCare,  Orion,  Antineoplastics,  Androgen receptor antagonists, Phase III, Prostate cancer, BAY 1841788,  ODM-201

O=C(N[C@@H](C)Cn1ccc(n1)c2ccc(C#N)c(Cl)c2)c3cc(nn3)C(O)C

OR

ULIXERTINIB

4-(5-chloro-2-isopropylaminopyridin-4-yl)-1H-pyrrole-2-carboxylic acid[1-(3-chlorophenyl)-2-hydroxyethyl]amide

BVD-523; BVD-ERK; BVD-ERK/HM; BVD-ERK/ST; VRT-0752271; VRT-752271; VX-271, V

Ulixertinib malonate

4-(5-chloro-2-isopropylaminopyridin-4-yl)-1H-pyrrole-2-carboxylic acid[1-(3-chlorophenyl)-2-hydroxyethyl]amide (referred to as ulixertinib malonate)

• Originator Vertex Pharmaceuticals
• Developer BioMed Valley Discoveries
• Class Aminopyridines; Antineoplastics; Pyrroles; Small molecules
• Mechanism of Action Mitogen activated protein kinase 3 inhibitors; Mitogen-activated protein kinase 1 inhibitor

Highest Development Phases

• Phase I/II Acute myeloid leukaemia; Cancer; Myelodysplastic syndromes
• Phase I Pancreatic cancer

Most Recent Events

• 01 Mar 2016 Phase-I clinical trials in Pancreatic cancer (Combination therapy, First-line therapy, Metastatic disease) in USA (PO) (NCT02608229)
• 23 Nov 2015 BioMed Valley Discoveries and Washington University School of Medicine plan a phase Ib trial for Pancreatic cancer (First-line therapy, Metastatic disease, Combination therapy) (PO) (NCT02608229)
• 01 Nov 2014 Phase-I/II clinical trials in Acute myeloid leukaemia (Second-line therapy or greater) and Myelodysplastic syndromes (Second-line therapy or greater) in USA (NCT02296242) (PO)

INTRODUCTION

Ulixertinib is in phase I/II clinical trials for the treatment of acute myelogenous leukemia (AML), myelodysplasia and advanced solid tumors.

Members of the family of B-cell CLL/lymphoma 2 proteins (BCL-2) are apoptosis regulators. These proteins control mitochondrial outer

membrane permeabilization (MOMP). Expression of BCL-2 protein blocks cell death in response to various cellular injuries. A number of cancers, including melanoma, breast, prostate, chronic lymphocytic leukemia, and lung cancer, may be caused by damage to the BCL-2 gene. Mutations in BCL-2 may also be a cause of resistance to cancer treatments. Unfortunately, resistance can quickly develop using conventional BCL-2 inhibitor therapies to treat cancer.

Extracellular-signal-regulated kinases (ERKs) are protein kinases that are involved in cell cycle regulation, including the regulation of meiosis, mitosis, and postmitotic functions in differentiated cells. Disruption of the ERK pathway is common in cancers. However, to date, little progress has been made developing effective ERK inhibitors for the treatment of cancer.

As the understanding of the molecular basis of cancer grows, there is an increased emphasis on developing drugs that specifically target particular nodes in pathways that lead to cancer. In view of the deficiencies noted above, there is, inter alia, a need for effective molecularly targeted cancer treatments, including combination therapies. The present invention is directed to meeting these and other needs.

Mitogen-activated protein kinase (MAPK) pathways mediate signals which control diverse cellular processes including growth, differentiation, migration, proliferation and apoptosis. One MAPK pathway, the extracellular signal-regulated kinase (ERK) signaling pathway, is often found to be up-regulated in tumors. Pathway members, therefore, represent attractive blockade targets in the development of cancer therapies (Kohno and Pouyssegur, 2006). For example, U.S. Patent No. 7,354,939 B2 discloses, inter alia, compounds effective as inhibitors of ERK protein kinase. One of these compounds, 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide, is a compound according to formula (I):

Pharmaceutical compositions are often formulated with a crystalline solid of the active pharmaceutical ingredient (API). The specific crystalline form of the API can have significant effects on properties such as stability and solubility / bioavailability. Instability and solubility characteristics can limit the ability to formulate a composition with an adequate shelf life or to effectively deliver a desired amount of a drug over a given time frame (Peterson et al., 2006).

Synergistic combination comprising an ERK1/2 inhibitor (such as ulixertinib) and a BCL-2 family inhibitor (such as navitoclax), assigned to BioMed Valley Discoveries (BVD), naming Decrescenzo and Welsch. BVD, presumably under license from Vertex, is developing ulixertinib (phase 2 trial), a small-molecule ERK 1/2 inhibitor for treating cancers including acute myelogenous leukemia and myelodysplastic syndrome. In June 2015, clinical data were presented at the 51st ASCO meeting in Chicago, IL.

BIOMED VALLEY DISCOVERIES

PATENT

WO2005113541 PDT PATENT

I-9 COMPD

SEE BELOW

PATENT

WO-2016123574

Novel crystalline forms of 4-(5-chloro-2-isopropylaminopyridin-4-yl)-1H-pyrrole-2-carboxylic acid[1-(3-chlorophenyl)-2-hydroxyethyl]amide (referred to as ulixertinib) can be prepared which exhibit improved properties, eg surprisingly improved stability and solubility characteristics. Also claimed is their use for treating cancer.

EXAMPLE 2

Preparation of Crystaline Free Base 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide

4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide free base was prepared according to the following synthesis scheme.

Stepl

C₅H₂CIFIN

257.43 C₈H₁₀CIIN₂

ASYM-11 1606 296.54

ASYM-1 12060

ASYM-111938 ASYM-112393

ASYM-1 11935

In Step 1 , a clean and dry 200 L glass-lined reactor was evacuated to <-0.08 MPa, and then filled with nitrogen to normal pressure three times. Anhydrous ethanol (49.90 kg) was charged into the 200 L glass-lined reactor. ASYM-1 1 1606 (Asymchem) (12.70 kg) and isopropylamine (29.00 kg) were added into the mixture in turn. The mixture was heated to 65-75°C for refluxing. The mixture reacted at 65-75°C. After 20 h, the reaction was sampled and analyzed by HPLC every 4-6 h until the content of ASYM-1 1 1606 was <1 %. The mixture was cooled to 40-45°C and was concentrated at <45°C under reduced pressure (<-0.08 MPa) until 13-26 Lremained. The organic phase was washed with a sodium chloride solution and was stirred for 20-30 min and settled for 20-30 min before separation. The organic phase was concentrated at <30°C under reduced pressure (<-0.06 MPa) until 13-20 L remained. Petroleum ether (8.55 kg) was added into the concentrated mixture. The mixture was transferred into a 20 L rotary evaporator and continued concentrating at <30°C under reduced pressure (<-0.06 MPa) until 13-20 L remained. Then petroleum ether (8.55 kg) was added into the concentrated mixture. The mixture was cooled to 0-5°C and stirred for crystallization. After 1 h, the mixture was sampled and analyzed by wt% every 1 -2 h until the wt% of the mother liquor was <1 1 % or the change of the wt% between consecutive samples was <1 %. The mixture was filtered with a 10 L filter flask. The filter cake was sampled and analyzed for purity by HPLC. 10.50 kg of product was recovered as a brownish yellow solid at 99.39% purity.

In Step 2, a clean and dry 300 L glass-lined reactor was evacuated to <-0.08 MPa, and then filled with nitrogen to normal pressure three times. Glycol dimethyl ether (73.10 kg) was charged into the 300 L glass-lined reactor at 20-30°C. ASYM-1 12060 (Asymchem) (10.46 kg) and ASYM-1 1 1938 (Asymchem) (12.34 kg, 1 1 .64 kg after corrected) were added into the mixture in turn under the protection of nitrogen. Maintaining the temperature at 20-30°C, purified water (10.50 kg) and anhydrous sodium carbonate (5.67 kg) were added into the mixture. Palladium acetate (0.239 kg) and tricyclohexylphosphonium tetrafluoroborate (0.522 kg) were added into the mixture under the protection of nitrogen. After addition, the mixture was evacuated to <-0.06 MPa, and then filled with nitrogen to normal pressure. This was repeated for ten times until residual oxygen was <300 ppm. The mixture was heated to 75-85°C for refluxing. The mixture reacted at 75-85°C. After 4 h, the mixture was sampled and analyzed by HPLC every 2-3 h for content of ASYM-

1 12060. The content of AS YM-1 12060 was 6.18%, so additional ASYM-1 1 1938 (0.72 kg) was added and continued reaction until the content of ASYM-1 12060 was <3%. The mixture was cooled to 25-35°C and filtered with a 30 L stainless steel vacuum filter. The filter cake was soaked and washed twice with THF (14.10kg). The filtrate and washing liquor were combined and concentrated at <50°C under reduced pressure (<-0.08 MPa) until 10-15 L remained. The mixture was cooled to 15-25°C. Methanol (1 1 .05 kg) was added into the concentrated mixture. Then the mixture was stirred for crystallization. After 2 h, the mixture was sampled and analyzed by HPLC every 2-4 h until the wt% of the mother liquor was <2%. The mixture was filtered with a 30 L stainless steel vacuum filter. The filter cake was soaked and washed twice with methanol (8.30 kg). The filter cake was transferred into a 50 L plastic drum. Then ethyl acetate (7.10 kg) and petroleum ether (46.30 kg) were added into the drum. The mixture was stirred for 1.5-2 h and then filtered with a nutsche filter. The filter cake was soaked and washed with petroleum ether (20.50 kg). The filter cake was dried in the nutsche filter under nitrogen at 30-40°C. After 8 h, the solid was sampled and Karl Fischer (KF) analysis was performed in intervals of 4-8 h to monitor the drying process. Drying was completed when the KF result was <1 .0% water. During drying, the solid was turned over and mixed every 4-6 h. 12.15 kg of product was recovered as a brownish yellow solid at 98.32% purity.

In Step 3, a clean and dry 300 L glass-lined reactor was evacuated to <-0.08 MPa, and then filled with nitrogen to normal pressure three times. THF (62.58 kg) was charged into the 300 L glass-lined reactor at 15-30°C. Then the stirrer was started. ASYM-1 12393 (12.00 kg, 1 1 .70 kg after corrected) was added into the mixture. The mixture was stirred until the solid dissolved completely. Maintaining the temperature at 15-30°C, a lithium hydroxide solution which was

prepared with lithium hydroxide monohydrate (5.50 kg) in purified water (70.28 kg) was added into the mixture. Then diethylamine (3.86 kg) was added. The mixture was heated to 60-70°C for refluxing. The mixture reacted at 60-70°C. After 30 h, the reaction was sampled and analyzed by HPLC every 4-6 h until the content of intermediate at relative retention time (RRT)=1 .39-1 .44 was <1 % and the content of ASYM-1 12393 was <1 %. HPLC conditions for this analysis are set forth in Table 1 .

Table 1 : HPLC Parameters

The mixture was cooled to 25-35°C and MTBE (25.97 kg) was added into the mixture. The mixture was stirred for 20-30 min and filtered via an in-line fluid filter. The filtrate was transferred into a 300 L glass-lined reactor and settled for 20-30 min before separation. The pH of the obtained aqueous phase was adjusted with a 6 N hydrochloric acid solution which was prepared from concentrated hydrochloric acid (14.86 kg) in purified water (10.88 kg) at the rate of 5-8 kg/h at 15-25°C until the pH was 1 -2. The pH of the mixture was adjusted again with a saturated sodium carbonate solution which was prepared from sodium carbonate (5.03 kg) in purified water (23.56 kg) at the rate of 3-5 kg/h at 15-25°C until the pH was 6.4-6.7. Then the pH of the mixture was adjusted with a hydrochloric acid solution which was prepared from concentrated hydrochloric acid (1 .09 kg) in purified water (0.80 kg) until the pH was 6.2-6.4. The mixture was filtered with a nutsche filter. The filter cake was transferred into a 300 L glass-lined reactor and purified water (1 17.00 kg) was added. The mixture was stirred and sampled and analyzed by HPLC until the p-toluenesulfonic acid residue of the filter cake was <0.5%. Then the mixture was filtered. The filter cake was dried in the tray drier under nitrogen at 55-65°C until KF<10%. The solid and MTBE (8.81 kg) were charged into a 50 L stainless steel drum. The mixture was stirred for 1 -2 h. The mixture was filtered with a 30 L stainless steel vacuum filter. The filter cake was dried in the nutsche filter at 50-60°C. After 8 h, the solid was sampled and analyzed by KF every 4-8 h until KF<5%. During drying, the solid was turned over and mixed every 4-6 h. 6.3 kg of product was recovered as an off-white solid at 98.07% purity.

In Step 4, a dry and clean 50 L flask was purged with nitrogen for 20 min. DMF (30.20 kg) was charged into the 50 L flask reactor. Then the stirrer was started. Maintaining the temperature at 15-25°C, ASYM-1 12394 (3.22 kg, 2.76 kg after corrected) was added into the mixture. The mixture was stirred until the solid dissolved completely. The mixture was cooled to -10 to -20°C and 1 -hydroxybenzotriazole hydrate (2.10 kg) was added into the mixture at -10 to -20°C. Then EDCI (2.41 kg) was added into the mixture in five portions at an interval of about 5-10 min. The mixture was cooled to -20 to -30°C and ASYM-1 1 1888 (Asymchem) (1 .96 kg) was added into the mixture at -20 to -30°C. Then DIEA (1 .77 kg) was added into the mixture at the rate of 3-4 kg/h. The mixture was heated to 15-25°C at the rate of 5-10°C/h. The mixture was reacted at 15-25°C. After 6-8 h, the mixture was sampled and analyzed by HPLC every 2-4 h until the content of ASYM-1 12394 was <2%. The mixture was cooled to 0-10°C and the reaction mixture was quenched with a solution which was prepared from ethyl acetate (28.80 kg) in purified water (12.80 kg) at 0-10°C. The mixture was extracted three times with ethyl acetate (28.80 kg). For each extraction the mixture was stirred for 20-30 min and settled for 20-30 min before separation. The organic phases were combined and washed twice with purified water (12.80 kg). The mixture was stirred for 20-30 min and settled for 20-30 min before separation for each time. Then the obtained organic phase was filtered through an in-line fluid filter. The filtrate was transferred into a 300 L glass-lined reactor. The mixture was washed twice with a 5% acetic acid solution, which was prepared from acetic acid (2.24 kg) in purified water (42.50 kg). The solution was added at the rate of 10-20 kg/h. The organic phase was washed twice with a sodium carbonate solution, which was prepared from sodium carbonate (9.41 kg) in purified water (48.00 kg). The organic phase was washed twice with a sodium chloride solution, which was prepared from sodium chloride (16.00 kg) in purified water (44.80 kg). The organic phase was transferred into a 300 L glass-lined reactor. Anhydrous sodium sulfate (9.70 kg) was added into the mixture and the mixture was stirred for 2-4 h at 15-30°C. The mixture was filtered with a nutsche filter, which was pre-loaded with about 1 cm thick silica gel (7.50 kg). The filter cake was soaked and washed with ethyl acetate (14.40 kg) before filtration. The filtrates were combined and the combined filtrate was added into a 72 L flask through an in-line fluid filter. The mixture was concentrated at T≤40°C under reduced pressure (P<-0.08 MPa) until 3-4 L remained. Then MTBE (4.78 kg) was added into the mixture. The mixture was cooled to 0-10°C for crystallization with stirring. After 1 h, the mixture was sampled and analyzed by wt% every 1-2 h until the wt% of the mother liquor was <5% or the change of wt% between consecutive samples was <1%. The mixture was filtered with a vacuum filter flask and the filter cake was dried in the tray drier under nitrogen at 30-40°C until KF<0.5%. 3.55 kg of product was recovered as an off-white solid at 100% purity.

EXAMPLE 3A

Preparation of 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide Form C

4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide Form C was prepared from 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide free base as follows. ASYM-1 1 1935 (10.4 kg) was added to a stirred mixture of anhydrous ethanol (73.9 kg), methanol (4.1 kg) and isopropanol (4.1 kg). The mixture was heated to 70-75°C and stirred until all the solids dissolved. Anhydrous HCI (37 wt%, 1 .1 eq) in a mixture of ethanol/methanol/isopropanol (90:5:5) was added and the mixture maintained at 70-75°C for 2 hours after the addition was completed. The mixture was then cooled to 15-25°C at a rate of 5-15°C per hour and stirred at this temperature until the desired polymorphic purity was reached. The end point of the crystallization/polymorph conversion was

determined by the absence of an XRPD peak at about 10.5° 2Θ in three successive samples.

The mixture was then filtered and washed successively with a pre-prepared solution of anhydrous ethanol (14.8 kg), methanol (0.8 kg) and isopropanol (0.8 kg), followed by MTBE (2 x 21 kg). Avoidance of delay in the washing of the filter cake is preferable because the polymorph may be unstable in the wet filter cake in the presence of reagent alcohol and improved stability was observed after the MTBE wash has been performed. The wet filter cake was then dried in a heated filter funnel or a tray drier at 40-50°C until dry. Typical yields were about 85-90%.

EXAMPLE 3B

Alternative Preparation of 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide Form C

ASYM-1 15985

4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide Form C was also prepared from 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide free base as follows. A dry and clean 72 L flask was purged with nitrogen for 20 min. Anhydrous ethanol (21 .35 kg) methanol (1 .17 kg) and isopropanol (1 .19 kg) were charged into the 72 L flask at 15-25°C and the mixture was stirred for 20-30 min. ASYM-1 1 1935 (3.01 kg) was added into the mixture and heated to 70-75°C at the rate of 15-25°C/h and stirred until the solid dissolved completely.

An alcohol / HCI solution was prepared as follows. Anhydrous ethanol (1.500 kg) methanol (0.088 kg) and isopropanol (0.087 kg) were charged into a 5 L flask at 15-25°C and the mixture was stirred for 20-30 min. The mixture was bubbled with hydrogen chloride through a dip tube under stirring at 10-25°C. After 2 h, the mixture was sampled and analyzed every 2-4 h until the wt% of hydrogen chloride was > 35%.

The alcohol / HCI solution (0.519 kg) prepared above was added dropwise into the mixture at the rate of 0.5-1.0 kg/h at 70-75°C. Seed crystal (0.009 kg) was added into the mixture and the alcohol / HCI solution (0.173 kg) prepared above was added into the mixture at the rate of 0.5-1 .0 kg/h at 70-75°C. After addition, the mixture was stirred for 1 -2 h at 70-75°C. The mixture was cooled to 15-25°C at the rate of 5-15°C/h and stirred for 4-6 h. The mixture was heated to 70-75°C at the rate of 15-25°C/h and stirred for 8-10 h at 70-75°C. The mixture was cooled to 15-25°C at the rate of 5-15°C/h and stirred for 4-6 h. The mixture was filtered with a vacuum filter flask. The filter cake was soaked and rinsed with a solution which was prepared from anhydrous ethanol (4.25 kg) and methanol (0.24 kg) and isopropanol (0.24 kg) before filtration. The filter cake was dried in a drying room under nitrogen at 40-50°C until the ethanol residue was <0.5% and methanol residue was <0.3% and isopropanol residue was <0.3%. 2.89 kg of product was recovered as a white solid at 99.97% purity.

PATENT

WO-2016123581

Novel crystalline malonate salt forms of 4-(5-chloro-2-isopropylaminopyridin-4-yl)-1H-pyrrole-2-carboxylic acid[1-(3-chlorophenyl)-2-hydroxyethyl]amide (referred to as ulixertinib malonate) and composition comprising them. Also claimed is their use for treating cancer.

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2016123581&redirectedID=true

EXAMPLE 6

Aqueous Disolution of 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1-(3-chlorophenyl)-2-hydroxyethyl]amide Malonate Form A

Samples of 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide Form C and 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2 -carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide malonate Form A were each shaken at ambient temperature in fasting state simulated gastric fluid (FaSSGF) pH 1.6 for 30 minutes. Concentration of 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide was measured at 5, 15 and 30 minutes.

After 30 minutes, the samples were removed from FaSSGF, placed in fasting state simulated intestinal fluid (FaSSIF) pH 6.5, with shaking, for an additional 5 hours. Concentration of 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide was measured at 10, 30, 60 90, 120, 180, 270, and 300 minutes. Results are summarized in Table 13 and shown in FIG. 10A (FaSSGF) and FIG. 10B (FaSSIF).

Table 13: Solubility of 4-(5-Chloro-2-isopropylaminopyridin-4-yl)-1 H-pyrrole-2-carboxylic acid [1 -(3-chlorophenyl)-2-hydroxyethyl]amide Form C and Malonate Form A.

PATENT

WO2016123574

PATENT

WO2015095834

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015095834&redirectedID=true

PATENT

WO2005113541

Example 1 Compound 1-9 was prepared as follows:

1-9

2,2,2-TrichIoro-l-(4-iodo-lH-pyrrol-2-yl)ethanone: To a stirred solution of 50 g (235 mmol, 1.0 equiv.) of 2,2,2-trichloro-l-(lH-pyrrol-2-yl)-ethanone in dry dichloromethane (400 mL) under nitrogen, a solution of iodine monochloride (39 g, 240 mmol, 1.02 equivalents) in of dichloromethane (200 mL) was added dropwise. The resulting mixture was stirred at room temperature for 2 hours. The solution was washed with 10% potassium carbonate, water, 1.0 M sodium thiosulfate, saturated sodium chloride, dried over sodium sulfate, filtered, and concentrated under reduced pressure. The solid was recrystallized from hexanes/methyl acetate to afford the title compound (68.5g, 86%) as a colorless solid (86%). MS FIA: 335.8, 337.8 ES-.

4-Iodo-lH-pyrrole-2-carboxyIic acid methyl ester: To a stirred solution of 2,2,2- trichloro-l-(4-iodo-lH-pyrrol-2-yl)ethanone (68g, 201 mmol, 1.0 equivalent) in dry methanol (400 mL) under nitrogen, was added a solution of sodium methoxide in methanol (4.37 M, 54 mL, 235 mmol, 1.2 equivalents) over 10 minutes. The resulting mixture was stirred at room temperature for 1 hour. The volatiles were removed under reduced pressure and the crude was then partitioned between water and tert- butylmethyl ether. The organic phase was separated, washed two times with water, saturated sodium chloride, dried over sodium sulfate, filtered and concentrated under vacuum to afford the title compound (48g, 96%) as a colorless solid, that was used directly without further purification.

4-Iodo-l-(toluene-4-sulfonyl)-lH-pyrrole-2-carboxylic acid methyl ester: 4-Iodo- lH-pyrrole-2-carboxylic acid methyl ester (24.6 g, 98 mmol, 1.0 equivalent) was dissolved in dichloromethane (150 mL) and triethylamine (30 mL, 215.6 mmol, 2.2 equivalents). 4-(Dimethylamino)pyridine (1.2 g, 9.8 mmol, 0.1 equivalent) and p- toluenesulfonylchloride (20.6 g, 107.8 mmol, 1.1 equivalents) were added and the reaction mixture was stirred for 16 hours at room temperature. The reaction was quenched with 1 M ΗC1 and the organic layer was washed with aqueous sodium bicarbonate and brine. After drying over magnesium sulfate, the solvent was removed under reduced pressure and the residue was crystallized from tert-butylmethyl ether, yielding the title compound as a pale yellow solid (30 g, 75%). R_t(min) 8.259 minutes.

4-(4,4,5,5-Tetramethyl-[l,3,2]dioxaborolan-2-yI)-l-(toluene-4-sulfonyl)-lH- pyrrole-2-carboxylic acid methyl ester: To a degassed solution of 4-iodo-l- (toluene-4-sulfonyl)-lH-pyrrole-2-carboxylic acid methyl ester (20 g, 49.4 mmol, 1.0 equivalent) and bis(pinacolato)diborane (15 g, 65 mmol, 1.3 equivalents) in DMF (200 mL) under nitrogen, was added dichloro[l,l ‘- bis(diphenylphosphino)ferrocene]palladium (II) dichloromethane adduct (3.6 g, 4.9 mmol, 0.1 equivalent). The reaction mixture was then stirred at 80 °C for 18 hours. After removing the DMF under reduced pressure, the resulting thick oil residue was suspended in diethyl ether (500 mL) and a solid precipitated immediately. This solid was removed by filtration and the filtrate was washed with IM HCl, water, brine and dried over MgS0 . Concentration afforded the title compound as a white solid and used without further purification (10 g, 50%). LC/MS: R_t(min) 4.6; 406.4 ES+. MS FIA: 406.2 ES+. ‘pfNMR δ 1.2 (s, 12H), 2.35 (s, 3H), 3.8 (s, 3H), 7.2 (m, 3H), 7.8 (d, 2H), 8.0 (s, IH).

N,N’-2-(5-Chloro-4-iodo-pyridyI)-isopropyIarnine:

Method A. (Microwave)

In a 10 mL microwave tube, 5-chloro-2-fluoro-4-iodopyridine (1.0 g, 3.9 mmol, 1.0 equivalent) was dissolved in DMSO (4.0 mL) and then ispropylamine (0.99 mL, 11.7 mmol, 3.0 equivalents) was added. The tube was sealed and placed under microwave irradiation for 600 sec at 150 °C. This reaction was repeated six times. The reaction mixtures were combined, then diluted in ethyl acetate and washed with water. After drying over sodium sulfate, the solvent was evaporated to afford the title compound as a thick brown oil (5.6 g, 80% ) which was used directly without further purification. R_t(min) 4.614; MS FIA: 296.9 ES+. ‘pfNMRsssssss δ 1.25 (d, 6H), 3.65 (m, IH), 7.15 (s, IH), 7.75 (s, IH).

Method B: (Thennal)

5-Chloro-2-fluoro-4-iodopyridine (400 mg, 1.55 mmol, 1.0 equivalent) was dissolved in ethanol (5.0 mL) and then isopropylamine (0.66 mL, 7.8 mmol, 5.0 equivalents) was added. The resulting solution was stirred at 80 °C for 48 hours. The reaction mixture was then diluted in ethyl acetate and washed with water. After drying over sodium sulfate, the solvent was evaporated and a thick brown oil was obtained, which was then purified by flash chromatography on silica gel eluting with mixtures of hexanes/ethyl acetate (from 99:1 to 80:20) to afford the title compound as a pale yellow solid (96 mg, 21%).

4-(5-Chloro-2-isopropylaminopyridin-4-yl)-l-(toluene-4-suIfonyl)-lH-pyrrole-2- carboxylic acid methyl ester: To a solution of N,N’-2-(5-chloro-4-iodo-pyridyl)- isopropylamine (0.53 g, 1.8 mmol, 1.0 equivalent) and 4-(4,4,5,5-tetramethyl- [l,3,2]dioxaborolan-2-yl)-l-(toluene-4-sulfonyl)-lH-pyrrole-2-carboxylic acid methyl ester (0.78 g, 1.8 mmol, 1.0 equivalent) in DME (4.0 mL) was added a solution of aqueous 2 M sodium carbonate (1.0 mL) followed by Pd(PPh₃)₄ (0.21 mg, 0.18 mmol, 0.1 equivalent). The microwave tube was sealed and the reaction mixture was irradiated by microwave for 1800 sec. at 170 °C. The cmde of six reactions were combined and diluted in ethyl acetate and washed with water. After drying the organic layer with sodium sulfate, the solvent was removed and the resulting thick oil was adsorbed on silica gel. The crude was then purified by flash chromatography on silica, eluting with hexanes/ethyl acetate mixtures (from 99:1 to 70:30) to afford the title compound as a yellow solid (3.1 g, 61% over two steps). R_t(min) 6.556. MS FIA: 448.1 ES+. ‘HNMR δ 1.45 (d, 6H), 2.5 (s, 3H), 3.81 (s, 3H), 6.8 (s, IH), 7.35 (s, IH),

7.4 (d, 2H), 8.0 (m ,3H), 8.3 (s, IH).

4-(5-Chloro-2-isopropylaminopyridin-4-yl)-l-(2,4,6-trimethylbenzenesulfonyl)- lH-pyrrole-2-carboxylic acid methyl ester: To a solution of N,N’-2-(5-chloro-4- iodo-pyridyl)-isopropylamine (96 mg, 0.32 mmol, 1.0 equivalent) and 4-(4,4,5,5- tetramethyl-[ 1 ,3,2]dioxaborolan-2-yl)- 1 -(2,4,6-trimethylbenzenesulfonyl)- lH-pyrrole- 2-carboxylic acid methyl ester (152 mg, 0.35 mmol, 1.1 equivalents) in DME (2 mL), was added a solution of aqueous 2 M sodium carbonate (0.2 mL) followed by Pd(PPh ) (37 mg, 0.032 mmol, 0.1 equivalent). The reaction mixture was stirred at 80 °C for 16 hours. The crude was diluted in ethyl acetate and washed with water. After drying the organic layer with sodium sulfate, the solvent was removed and the resulting thick oil was adsorbed on silica gel. The cmde was then purified by flash chromatography on silica, eluting with hexanes/ethyl acetate mixtures (from 99:1 to 80:20) to afford the title compound as a yellow solid (65 mg, 43%). R_t(min) 7.290. MS FIA:476.1 ES+.

4-(5-Chloro-2-isopropylaminopyridin-4-yl)-lH-pyrrole-2-carboxyIic acid:

Method A. (Microwave)

A solution of 4-(5-chloro-2-isopropylaminopyridin-4-yl)-l-(toluene-4-sulfonyl)-lH- pyrrole-2-carboxylic acid methyl ester (3.1 g, 6.9 mmol, 1.0 equivalent) in TΗF (2.0 mL) was added to a solution of lithium hydroxide monohydrated (710 mg, 17.3 mmol,

2.5 equivalents) in water (3.0 mL). The microwave tube was sealed and the reaction mixture was irradiated by microwave for 1200 sec. at 150 °C. The cmde solution was acidified with aqueous 6Ν ΗC1. The solvent was evaporated off to afford the title compound which was used directly without further purification. R_t(min): 3.574. FIA MS: 279.9 ES+; 278.2 ES-.

Method B: (Thermal)

A solution of 4-(5-chloro-2-isopropylaminoρyridin-4-yl)-l-(2,4,6- trimethylbenzenesulfonyl)-lH-pyrrole-2-carboxylic acid methyl ester (0.69 g, 1.4 mmol, 1.0 equivalent) in TΗF (3.0 mL) was added to a solution of lithium hydroxide monohydrated (1.19 g, 29 mmol, 20.0 equivalents) in water (3.0 mL). The mixture was then refluxed for 8 hours. The cmde solution was acidified with aqueous 6N ΗC1 until cloudy, the organic solvent was partially removed and the product precipitated. The title compound was isolated by filtration and washed with water and diethyl ether, yielding a white solid (0.38 g, 96%).

4-(5-Chloro-2-isopropylaminopyridin-4-yl)-lH-pyrrole-2-carboxyIic acid [l-(3- ch!orophenyl)-2-hydroxyethyl] amide: To a suspension of 4-(5-chloro-2- isopropylaminopyridin-4-yl)-lH-pyrrole-2-carboxylic acid (1.93 g, 6.9 mmol, 1.0 equivalent) in DMF (5.0 mL) was added EDCI (1.45 g, 7.6 mmol, 1.1 equivalents), ΗOBt (0.94 g, 6.9 mmol, 1.0 equivalent) and (5)-3-chlorophenylglycynol (1.58 g, 7.6 mmol, 1.1 equivalents). Dusopropylethylamme (2.7 mL) was then added and the resulting mixture was stirred a room temperature overnight. The mixture was then poured into water and extracted with ethyl acetate. After drying over sodium sulfate, the solvent was removed and the crude was adsorbed on silica gel. Purification was effected by flash chromatography on silica, eluting with mixtures of hexanes/acetone (from 80:20 to 60:40) to afford the title compound as white solid (1.9 g, 64%). R_t(min) 4.981s. FIA MS: 433.1 ES+; 431.2 ES-. ¹ΗNMR (CD₃OD) δ 1.31 (d, 6H), 3.85 (m, 3H), 5.15 (t, IH), 7.01 (s, IH), 7.25 (m, 3H), 7.4 (s, IH), 7.45 (s, IH), 7.7 (s, IH), 7.95 (s, IH).

Example 2 Compound 1-9 was also prepared according to following alternate method:

2,5-DichIoro-4-nitropyridine N-oxide: To a suspension of 2-chloro-5-chloropyridine (10 g, 0.067 mol) in acetic anhydride (25 mL) was added hydrogen peroxide 30% (25 mL) in small portions. This mixture was stirred at room temperature for 24 hours and then heated at 60 °C for 30 hours. After removing the excess of acetic acid under reduced pressure, the residue was added in small portions to concentrated sulfuric acid (15 mL). The resulting solution was added to a mixture of concentrated sulfuric acid (15 mL) and fuming nitric acid (25 mL) and then heated at 100 °C for 90 minutes. The reaction mixture was poured on ice, neutralized with solid ammonium carbonate and finally with aqueous ammonia until a basic pH was obtained and. A precipitate formed. The precipitate was collected by filtration to afford the title compound as a pale yellow solid (3.1 g), R_t(min) 3.75. MS FIA shows no peak. ‘pfΝMR (DMSO-de) δ 8.78 (s, IH), 9.15 (s, IH).

4-Bromo-2-chloro-5-N-isopropylpyridin-2-amine N-oxide: To 2,5-dichloro-4- nitropyridine Ν-oxide (400 mg, 1.9 mmol) was added acetyl bromide (2 mL) very slowly. The reaction mixture was then heated at 80 °C for 10 minutes. The solvent was removed under a stream of nitrogen and the cmde product was dried under high vacuum. The cmde material (165 mg, 0.62 mmol) was dissolved in ethanol (2 mL), z^‘so-propylamine (0.53 mL) added and the resulting mixture was heated at 80 °C for 2 hours. The cmde solution was then purified by reversed phase HPLC (acetonitrile/water/TFA 1%) to afford the title compound as a pale yellow solid (60 mg, 36.6%). R_t(min) 5.275. MS FIA264.8, 266.9 ES+.

4-(5-chloro-2-isopropylaminopyridin-4-yl)-lH-pyrrole-2-carboxylic acid [l-(3- chlorophenyl)-2-hydroxyethyl] amide (1-9): 4-Bromo-2-chloro-5-N- isopropylpyridin-2-amine N-oxide (25 mg, 0.094 mmol, 1.0 equivalent) and 4- (4,4,5, 5-tetramethyl-[l,3,2]dioxaborolan-2-yl)-l-(2,4,6-trimethylbenzensulfonyl)-lH- pyrrole-2-carboxylic acid methyl ester (39 mg, 0.094 mmol, 1.0 equivalent) were dissolved in benzene (5 mL) then aqueous 2M Νa₂C0₃ (1 mL) and Pd(PPh₃)₄ (115.6 mg, 0.1 mmol, 0.2 equivalent) were added and the resulting suspension was heated at reflux at 80 °C for 16 hours. The reaction mixture was diluted in ethyl acetate, washed with water and dried over anhydrous sodium sulfate to afford 4-(5-chloro-2- isopropylamino-pyridin-4-yl)- 1 -(2,4,6-trimethyl-benzenesulfonyl)- lH-pyrrole-2- carboxylic acid methyl ester N-oxide (R (min) 6.859. MS FIA: 492.0 ES+) which was then treated with a 2 M solution of PC1₃ in dichloromethane (1 mL) at room temperature. After 10 minutes, the solvent was removed under a stream of nitrogen and the cmde oil was dissolved in methanol (1 mL) and aqueous 1 M ΝaOΗ (1 mL). The resulting mixture was heated at reflux for 16 hours then the cmde solution was acidified using aqueous 1 M ΗC1 and the solvent was removed. The resulting 4-(5- chloro-2-isopropylamino-pyridin-4-yl)-lΗ-pyrrole-2-carboxylic acid (R (min) 3.527. MS FIA: 279.4 ES+; 278.2 Es-) was suspended in DMF (3 mL) together with EDCI (36 mg, 0.19 mmol, 2 equivalents), HOBt (26 mg, 0.19 mmol, 2 equivalents), (S)-3- chlorophenylglycinol HCl salt (59 mg, 0.28 mmol, 3 equivalents) and DIEA (0.12 mL, 0.75 mmol, 8 equivalents). The resulting mixture was stirred at room temperature for 16 hours. The reaction mixture was diluted in ethyl acetate, washed with water and dried over sodium sulfate. After removing the solvent under reduced pressure, the cmde product was purified by reversed phase HPLC (acetonitrile/water/TFA 1%) to afford the title compound as a white solid (4.8 mg, 8.1%).

PATENT

US20150512092015-02-19COMPOUNDS AND COMPOSITIONS AS INHIBITORS OF MEK

US73549392008-04-08Pyrrole inhibitors of ERK protein kinase, synthesis thereof and intermediates thereto

Research scientist Tony Huang works in a laboratory at Vertex Pharmaceuticals Inc. in San Diego

REFERENCES

1 . Kohno M, Pouyssegur J (2006) Targeting the ERK signaling pathway in cancer therapy. Ann Med 38: 200-21 1 .

2. Kuby, J., Immunology, 3rd Ed., W.H. Freeman & Co., New York.

3. Lee DC, Webb ML(2003) Pharmaceutical Analysis. John Wiley & Sons, Inc., New York: 255-257.

4. Peterson ML, Hickey MB, Zaworotko MJ and Almarsson O (2006) Expanding the Scope of Crystal Form Evaluation in Pharmaceutical Science. J Pharm Pharmaceut Sci 9(3):317-326.

5. Pierce Catalog and Handbook, 1994-1995; Pierce Chemical Co., Rockford, III.

6. Remington, The Science and Practice of Pharmacy (21 st Edition, Lippincott Williams and Wilkins, Philadelphia, PA.

7. The United States Pharmacopeia-National Formulary, The United States Pharmacopeial Convention, Rockville, MD.

Gabriel Martinez-Botella

///////////ULIXERTINIB, BVD-523; BVD-ERK,  BVD-ERK/HM,  BVD-ERK/ST,  VRT-0752271,  VRT-752271,  VX-271, уликсертиниб ,أوليكسيرتينيب  ,优立替尼 , PHASE 2,  Vertex Pharmaceuticals, BioMed Valley Discoveries, UNII:16ZDH50O1U,  869886-67-9 , Gabriel Martinez-Botella

CC(C)NC1=NC=C(C(=C1)C2=CNC(=C2)C(=O)NC(CO)C3=CC(=CC=C3)Cl)Cl

Piramal Enterprises Limited announced that its wholly owned subsidiary in the U.S. has entered into an agreement to acquire 100 percent stake in Ash Stevens Inc., a U.S.-based contract development and manufacturing organization (CDMO), in an all cash deal for a consideration of USD $42.95 million plus an earn-out consideration capped at $10 million. This potential transaction is expected to be completed by the end of August.

Located in Riverview, Michigan, Ash Stevens has over 50 years of experience in contract manufacturing, and serves several biotech, mid-size pharma, and large pharmaceutical clients worldwide.

With over 60,000 sq. ft. of facilities, eight chemical drug development and production laboratories, and six full-scale production areas, Ash Stevens has built a stellar reputation, led by science, driven by operational excellence, and one that emphasizes quality as a culture. As one of the leaders in HPAPI manufacture, Ash Stevens has an impeccable safety record of working with high potency anti-cancer agents and other highly-potent therapeutics. The state-of-the-art manufacturing facility in Michigan features all necessary engineering and containment controls for the safe handling and cGMP manufacture of small and large-scale HPAPIs, with Occupational Exposure Limits (OELs) ≤ 0.1µg/m3. The facility has approvals from U.S., EU, Australia, Japan, Korea, and Mexico regulatory agencies.

“The acquisition of Ash Stevens fits well with our strategy to build an asset platform that offers value to our partners and collaborators. Currently, around 25 percent of the molecules in clinical development are potent. Our clients are looking for reliable partners that can assist them in advancing these programs forward,” said Vivek Sharma, CEO of Piramal Pharma Solutions. He further adds, “North America is a key market that we can now service with our three local facilities – the Coldstream Labs in Kentucky for fill finish needs, the Torcan facility in Toronto for complex high value APIs and now, Ash Stevens in Michigan for HPAPIs. Having facilities with a differentiated platform and geographical proximity to clients are keys towards building strategic partnerships. We expect this acquisition to also be synergistic with our Antibody Drug Conjugates (ADCs) and injectable business. We can now fulfill client requirements for a single source of supply for both high potent APIs and drug products.”

“With its rich history of scientific excellence, a track record of 12 product launches, Ash Stevens is well poised to become the partner of choice for clients looking to advance programs from early development through launch. In addition to the business benefits that the combined entity will bring to our clients, I am also pleased that the firms share common core values: both were founded by successful entrepreneurs, value integrity, and are committed to a customer-first approach,” said Dr. Mark Cassidy, President of the API Business at Piramal Pharma Solutions. “I am pleased to welcome the Ash Stevens team into the Piramal group. We expect them to be an integral part of our future growth plans.”

Added Dr. Stephen Munk, CEO of Ash Stevens, “We look forward to working with the Piramal leadership and management team, to develop API solutions that benefit customers and improve the lives of patients. The commitment that Piramal has shown towards growing its healthcare businesses, coupled with the complementary capabilities that our two firms have, makes this an exciting time for Ash Stevens and our employees. We have already identified areas where we can create significant value together, and will be moving forward rapidly to achieve those objectives.”

The transaction is not subject to any regulatory approvals. No related party of PEL has any interest in Ash Stevens.

Wells Fargo Securities, LLC served as exclusive financial advisor to Ash Stevens, with legal counsel provided by Morrison & Foerster LLP.

For further information on the financials, please visit our website: www.piramal.com.

Dr. Stephen A. Munk, President and CEO of Ash Stevens Inc.

Large scale reactor train with 2000, 3000, and 4000 L glass-lined reactors equipped with split butterfly valves.

Ash Stevens’ down draft kilo suite with low temperature capability.

Ajay Piramal

////////////CDMO,  Ash Stevens, Piramal Enterprises, Stephen A. Munk

Anders Eriksson, Matti Lepistö, Michael Lundkvist, af Rosenschöld Magnus Munck,Pavol Zlatoidsky,

Astrazeneca Ab INNOVATOR

• OriginatorAstraZeneca
• Class
• Mechanism of ActionMatrix metalloproteinase inhibitors
• Highest Development Phases

• DiscontinuedChronic obstructive pulmonary disease

Most Recent Events

• 29 Jul 2010Discontinued – Phase-II for Chronic obstructive pulmonary disease in Europe (PO)
• 29 Jul 2010Discontinued – Phase-I for Chronic obstructive pulmonary disease in Japan (PO)
• 29 Jul 2010Discontinued – Phase-I for Chronic obstructive pulmonary disease in Japan (PO)

AZD1236 is a selective MMP-9 and MMP-12 inhibitor (IC50 4.5 and 6.1nM) from Astrazeneca that, since it failed biomarker endpoints for COPD is included in the AZ Open Innovation 2014 set for repurposing. Pending any published link the structure identification is tenatative but seems likely to be the structure crystalised in WO2007106022.

Matrix metallopeptidase 9 and 12 (MMP9|MMP12) inhibitor http://www.ncbi.nlm.nih.gov/gene/4318; http://www.ncbi.nlm.nih.gov/gene/4321 Preclinical Pharmacology AZD1236 is a potent and reversible inhibitor of human MMP9 and MMP12 (IC50’s = 4.5 and 6.1nM, respectively), with 10 – 15-fold selectivity to MMP2 and MMP13 and >350-fold selectivity to other members of the enzyme family. Its activity is approximately 20- to 50-fold lower at the rat, mouse, and guinea pig orthologues. In acute models of lung injury, AZD1236 inhibited the hemorrhage and inflammation induced by instillation of human MMP12 into rat lungs by ~80% at 0.81 mg/kg, and also abolished macrophage infiltration into BAL fluid induced by tobacco smoke inhalation in the mouse. Safety and Tolerability In healthy human volunteers, AZD1236 was well tolerated in single doses from 2 to 1500 mg and in multiple doses of 15, 75 and 500 mg for periods of up to 13 days. AZD1236 was also well tolerated in COPD patients with moderate to severe disease when given at 75 mg BID for 6 weeks. Pre-clinical toxicology studies of up to 12 month duration have been performed. Toxicologically important findings mainly relate to chronic treatment and included: diffuse eye lens opacities after 6 months administration to rats and fibrodysplasia in the subcutis after 12 months to dogs. Clinical Pharmacology Target coverage data to date have been mixed. In healthy subjects, single dose of 30 or 75 mg inhibited ex vivo zymosanstimmulated whole blood MMP activity (the 75 mg dose yielding plasma compound levels at Cmax steady state of ~120 x IC50). In contrast, 75 mg BID for 6 wks in COPD patients compared to placebo did not identify any significant change in whole blood MMP activity.

PATENT

WO 2002074750 

WO 02/074767 further discloses a specific metalloproteinase inhibitor compound identified therein as (5S)-5-[4-(5-chloro-pyridin-2-yloxy)-piperidine-l-sulfonylmethyl]-5- methyl-imidazolidine-2,4-dione (page 65, lines 15 to 27; and page 120, lines 23 to 29). This compound is designated herein as compound (I).

(I)

WO 02/074767 further discloses processes for the preparation of compound (I). Thus, in one embodiment, compound (I) is prepared by a route analogous to that shown in the following Scheme (WO 02/074767; pages 87, 113 and 120) but substituting the appropriate amine in step (d):

Scheme 1

Reagents and conditions for Scheme 1: a) KCN, (NHLj)₂CO₃, EtOHTH₂O, +90⁰C, 3h;. b) Chiral separation, CHIRALPAK AD, methanol as eluent;. c) Cl₂ (g), AcOH/H₂O, <+15 ⁰C, 25min; d) Diisopropylethylamine, THF. -20 ⁰C, 30 min.

The obtained compound (I) is then purified either by precipitation and washing with ethanol/water or by preparative HPLC. In a second embodiment, the racemate of compound (I), (5RS)-5-[4-(5-chloro-pyridin-2- yloxy)-piperidine-l-sulfonylmethyl]-5-methyl-imidazolidine-2,4-dione, was prepared by reacting l-[4-(5-chloro-pyridin-2-yloxy)-piperidine-l-sulfonyl]-propan-2-one with an excess of potassium cyanide and ammonium carbonate in ethanol, and isolating the product by precipitation. Compound (I), the (5S)-enantiomer, was then obtained by chiral HPLC (WO 02/074767; pages 55 and 65).

No crystalline forms of compound (I) are disclosed in WO 02/074767.

Compound (I) is a potent metalloproteinase inhibitor, particularly a potent inhibitor of

MMP 12, and as such is useful in therapy. However, when made according to the processes described in WO 02/074767, compound (I) exhibits unpredictable solid state properties with respect to thermodynamic stability. To prepare pharmaceutical formulations containing compound (I) for administration to humans in accordance with the requirements of U.S. and other international health registration authorities, there is a need to produce compound (I) in a stable form, such as a stable crystalline form, having constant physical properties.

PATENT

WO  2007106022

WO 02/074767 further discloses a specific metalloproteinase inhibitor compound identified therein as (5S)-5-[4-(5-chloro-pyridin-2-yloxy)-piperidine-l-sulfonylmethyl]-5- methyl-imidazolidine-2,4-dione (page 65, lines 15 to 27; and page 120, lines 23 to 29). This compound is designated herein as compound (I).

(I)

WO 02/074767 further discloses processes for the preparation of compound (I). Thus, in one embodiment, compound (I) is prepared by a route analogous to that shown in the following Scheme (WO 02/074767; pages 87, 113 and 120) but substituting the appropriate amine in step (d):

Scheme 1

Reagents and conditions for Scheme 1: a) KCN, (NHLj)₂CO₃, EtOHTH₂O, +90⁰C, 3h;. b) Chiral separation, CHIRALPAK AD, methanol as eluent;. c) Cl₂ (g), AcOH/H₂O, <+15 ⁰C, 25min; d) Diisopropylethylamine, THF. -20 ⁰C, 30 min.

The obtained compound (I) is then purified either by precipitation and washing with ethanol/water or by preparative HPLC. In a second embodiment, the racemate of compound (I), (5RS)-5-[4-(5-chloro-pyridin-2- yloxy)-piperidine-l-sulfonylmethyl]-5-methyl-imidazolidine-2,4-dione, was prepared by reacting l-[4-(5-chloro-pyridin-2-yloxy)-piperidine-l-sulfonyl]-propan-2-one with an excess of potassium cyanide and ammonium carbonate in ethanol, and isolating the product by precipitation. Compound (I), the (5S)-enantiomer, was then obtained by chiral HPLC (WO 02/074767; pages 55 and 65).

No crystalline forms of compound (I) are disclosed in WO 02/074767.

Compound (I) is a potent metalloproteinase inhibitor, particularly a potent inhibitor of

MMP 12, and as such is useful in therapy. However, when made according to the processes described in WO 02/074767, compound (I) exhibits unpredictable solid state properties with respect to thermodynamic stability. To prepare pharmaceutical formulations containing compound (I) for administration to humans in accordance with the requirements of U.S. and other international health registration authorities, there is a need to produce compound (I) in a stable form, such as a stable crystalline form, having constant physical properties.

A preferred process for the synthesis of compound (I) is shown in Scheme 2.

Scheme 2

KCN, (NH₄)₂CO₃

(H) 2-propanol

Chromatography KOBu’

Cl₂

AcOH AcOH, H₂O

Compound (I)

Recrystallisation EtOH, H₂O

Compound (I) Form G

Example 5

(S)-5-[4-(5-ChIoro-pyridin-2-yloxy)-piperidine-l-suIfonylmethyl]-5-methyl- imidazoIidine-2,4-dione Process 1

I₅ a) 5-Chloro-2-(piperidin-4-yloxy)-pyridine

5-Chloro-2-(piperidin-4-yloxy)-pyridine acetate (40 g, 0.146 mol) was slurried in iso- PrOAc (664 mL) at 30⁰C. To this slurry was added Na₂CO₃ (1.5 mol per litre; 196 mL, 2 mol eq.). The slurry was then rapidly stirred at 30 ⁰C for 15 minutes. The biphasic mixture was allowed to settle, and the bottom aqueous phase was separated and discarded.

20 The above base washing procedure was repeated twice more. The organic phase was then washed once with water (200 mL). The resulting iso-VxOAc solution was reduced in volume to approximately 300 mL by distillation under reduced pressure. The solution was then diluted with zsø-PrOAc (400 mL) and again distilled down to approximately 300 mL. This procedure was repeated once more. A sample was removed for analysis of 5-chloro-

25 2-(piperidm-4-yloxy)-pyridine content and water content. The weight or the volume of the solution was measured in order to calculate the concentration of 5-chloro-2-(piperidin-4- yloxy)-pyridme in the Z-PrOAc solution.

fr) rSV5-r4-(5-Chloro-pyridin-2-yloxyVpiperidine-l-sulfonylmethvn-5-methyl- 30 imidazolidine-2 ,4-dione Diisopropylethylamine (24.3 mL, 0.139 mol, 1 mol eq.) was added to the iso-PrOAc solution prepared in part (a) [ca. 300 mL; equivalent to 31.2 g, 0.146 mol, 1.05 mol eq. of 5-chloro-2-(piperidin-4-yloxy)-pyridine] in one portion at RT. The solution was then cooled to -15 °C.

((S)-4-Methyl-2,5-dioxo-imidazolidin-4-yl)-methanesulfonyl chloride (31.65 g, 0.139 mol, 1 mol eq.) was dissolved in dry THF (285 mL) at RT with stirring. The resulting solution was then added to the iso-PrOAc solution of 5-chloro-2-(piperidin-4-yloxy)- pyridine dropwise at -15 ⁰C over about 1.5 h. A precipitate was seen on addition of the ((S)-4-methyl-2,5-dioxo-imidazolidin-4-yl)-methanesulfonyl chloride. At the end of the addition, dry THF (32 mL) was added to the reaction mixture to wash the line and the mixture was stirred for 1 h at — 15 ⁰C. It was then warmed to 20 °C over 1 h and stirred at 20 °C for 1 h further. The reaction was quenched with 10 wt% NaHSO₄ (157 mL) with rapid stirring. After about 15 minutes, the biphasic mixture was allowed to settle, and the bottom aqueous phase was separated and discarded. This acid wash procedure was repeated once more. The organic phase was then washed with water (157 mL) using rapid stirring and allowing complete phase separation before partitioning. The reaction solution was then warmed to 40 °C and washed again with water (157 mL). THF (95 mL) was added to the organic layer that was then warmed to 40 ⁰C and filtered at 40⁰C to remove any particulate matter. The solvent volume was then reduced to about 157 mL by reduced pressure distillation with the jacket temperature at 55 °C. zso-PrOAc (317 mL) was then added and the volume was again reduced to about 157 mL. Two more put-and-takes of zsø-PrOAc (317 mL) were carried out. Solids began to precipitate out during the distillations and a suspension resulted. The volume was reduced to about 157 mL each time and after the final distillation a small sample of solvent was then removed from the reaction mixture for residual THF analysis. The ¹H NMR showed no THF peaks. The contents of the reaction were then cooled to 0 °C and the product was collected by filtration. The reaction vessel was washed with zsø-PrOAc (63 mL) and this rinse was used to wash the product on the filter. The product was dried overnight in a vacuum oven at 40 °C. The required (S)-5-[4- (5-chloro-pyridin-2-yloxy)-piperidine-l-sulfonyhnethyl]-5-methyl-imidazolidine-2,4-dione was isolated as a white solid in 71% yield (41.8 g).

¹H NMR (300MHz, d6-DMSO) δ 10.74 (IH, s), 8.20 (IH, d), 8.01 (IH, s), 7.81 (IH, dd), 6.87 (IH, d), 5.09 (IH, m), 3.52-3.35 (4H, m), 3.13 (2H, m), 2.02 (2H, m), 1.72 (2H, m), 1.33 (3H, s).

Example 6

(S)-5-[4-(5-Chloro-pyridin-2-yloxy)-piperidine-l-sulfonylmethyl]-5-methyl- imidazolidine-2,4-dione Process 2 a) 5-Chloro-2-(piperidm-4-yloxy)-pyridine

5-Chloro-2-(piperidm-4-yloxy)-pyridine acetate (70 g, 257 mmol) was slurried in toluene

(560 mL) at RT. IM NaOH (420 mL) was added and the slurry was then rapidly stirred at RT for 15 min. The biphasic mixture was allowed to settle, and the bottom aqueous phase was separated and discarded. The organic phase was then washed with water (2 x 420 mL). A sample was removed from the organic phase and assayed for 5-chloro-2-(piperidin-

4-yloxy)-pyridine.

The resulting toluene solution was then reduced in volume by distillation at reduced pressure, down to approximately 168 mL (2.4 vol eq. with respect to 5-chloro-2-(piperidin-

4-yloxy)-pyridine acetate charge). The solution was then diluted with toluene (420 mL) and again distilled down to approx 168 mL (2.4 vol eq.). A sample was removed for analysis of water content.

b^*) (S)-5-r4-r5-Chloro-pyridm-2-yloxy)-piperidine-l-sulfonylmethvH-5-methyl- imidazolidine-2 ,4-dione

Diisopropylethylamine (38.4 mL, 220 mmol) was added to the toluene solution of 5-chloro-2-(piperidin-4-yloxy)-pyridine obtained in step (a) (containing 236 mmol) in one portion followed by dry THF (151 mL) as a line wash. ((S)-4-Methyl-2,5-dioxo- imidazolidin-4-yl)-methanesulfonyl chloride (48.7 g, 215 mmol) was dissolved in dry THF (352 mL) at RT with stirring. The resulting solution of the sulfonyl chloride was then added dropwise to the toluene/THF solution of 5-chloro-2-(piperidin-4-yloxy)-pyridine and diisopropylethylamine at RT over 1 to 2 h. A precipitate was seen on addition of the sulfonyl chloride. At the end of the addition, dry THF (50 mL) was added to the reaction 5 mixture as a line wash. After the addition was complete, the reaction was stirred for about 30 min at RT.

The reaction was quenched with 10 wt% NaHSO₄ (251 mL) with rapid stirring for approx 15 min. The biphasic mixture was allowed to settle, when the bottom aqueous phase was io separated and discarded. This acid wash procedure was repeated once more. The solvent volume was then reduced to about 220 mL by reduced pressure distillation. Toluene (300 mL) was then added and the volume was reduced to about 245 mL Solids begin to precipitate during the distillations and a suspension resulted. After the final distillation, a small sample of solvent was then removed from the reaction mixture for residual THF i₅ analysis.

The contents of the reaction mixture were then cooled to 0 °C, stirred for about 30 minutes at this temperature and the product was collected by filtration. The reaction vessel was washed with toluene (100 mL) and this rinse was used to wash the product on the filter. 20 The product was dried in a vacuum oven at 40 ⁰C to constant weight. (S)-5-[4-(5-Chloro- pyridin-2-yloxy)-piperidine-l-sulfonylmethyl]-5-methyl-imidazolidine-2,4-dione was isolated as a white solid in typically 85 to 88% yield over the two steps.

Aerial view of Mölndal

Patent

WO 2003106689

Paul Hudson, President, AstraZeneca U.S. and Executive Vice President, North America, joined by AstraZeneca volunteers to celebrate the AstraZeneca Hope Lodge’s fifth birthday.

CLIPS

Astra boss Pascal Soriot

Massachusetts Economic Development Secretary Jay Ash (left) congratulates Kumar Srinivasan, Head of AstraZeneca R&D Boston (right), at a ceremony to launch AstraZeneca’s Gatehouse Park BioHub.

https://ncats.nih.gov/files/AZD1236.pdf

///////AZD1236,  AZD-1236, AZD 1236,

O=S(=O)(C[C@@]1(C)NC(=O)NC1=O)N3CCC(Oc2ccc(Cl)cn2)CC3

Osanetant (SR-142,801)

160492-56-8 CAS

(R)-(+)-N-[[3-[1-benzoyl-3-(3,4-dichlorophenyl)piperidin-3-yl]prop-1-yl]-4-phenylpiperidin-4-yl]-N-methylacetamide

Osanetant (SR-142,801) was a neurokinin 3 receptor antagonist developed by Sanofi-Synthélabo, which was being researched for the treatment of schizophrenia, but was discontinued.^[1][2] It was the first non-peptide NK₃ antagonist developed in the mid-1990s,^[3][4] Other potential applications for osanetant is in the treatment of drug addiction, as it has been found to block the effects ofcocaine in animal models.^[5][6]

Developed by Sanofi-Aventis (formerly Sanofi-Synthelabo), osanetant (SR-142801) is an NK3 receptor antagonist which was under development for the treatment of schizophrenia and other Central Nervous System (CNS) disorders. In a review of its R&D portfolio, the company announced in August 2005 that it would cease any further development ofosanetant. This follows an earlier decision to discontinue development of eplivanserin for schizophrenia

References

1.  “osanetant Sanofi-Aventis discontinued, France.”. Highbeam.
2. Kamali, F (July 2001). “Osanetant Sanofi-Synthélabo”. Current opinion in investigational drugs (London, England : 2000). 2 (7): 950–6.PMID 11757797.
3.  Emonds-Alt, X; Bichon, D; Ducoux, JP; Heaulme, M; Miloux, B; Poncelet, M; Proietto, V; Van Broeck, D; et al. (1995). “SR 142801, the first potent non-peptide antagonist of the tachykinin NK3 receptor”. Life Sciences. 56 (1): PL27–32. doi:10.1016/0024-3205(94)00413-M.PMID 7830490.
4.  Quartara L, Altamura M (August 2006). “Tachykinin receptors antagonists: from research to clinic”. Current Drug Targets. 7 (8): 975–92.doi:10.2174/138945006778019381. PMID 16918326. Retrieved 2011-04-14.
5.  Desouzasilva, M; Mellojr, E; Muller, C; Jocham, G; Maior, R; Huston, J; Tomaz, C; Barros, M (May 2006). “The tachykinin NK3 receptor antagonist SR142801 blocks the behavioral effects of cocaine in marmoset monkeys”. European Journal of Pharmacology. 536 (3): 269–78.doi:10.1016/j.ejphar.2006.03.010. PMID 16603151.
6.  Jocham, Gerhard; Lezoch, Katharina; Müller, Christian P.; Kart-Teke, Emriye; Huston, Joseph P.; De Souza Silva, M. AngéLica (September 2006). “Neurokinin receptor antagonism attenuates cocaine’s behavioural activating effects yet potentiates its dopamine-enhancing action in the nucleus accumbens core”. European Journal of Neuroscience. 24 (6): 1721–32. doi:10.1111/j.1460-9568.2006.05041.x.PMID 17004936.

Osanetant

Systematic (IUPAC) name
N-(1-{3-[(3R)-1-benzoyl-3-(3,4-dichlorophenyl)piperidin-3-yl]propyl}-4-phenylpiperidin-4-yl]-N-methylacetamide
Identifiers
CAS Number	160492-56-8
ATC code	none
PubChem	CID 219077
IUPHAR/BPS	2110
ChemSpider	189901
UNII	K7G81N94DT
ChEMBL	CHEMBL346178
Chemical data
Formula	C35H41Cl2N3O2
Molar mass	606.625 g/mol

///////Osanetant , SR-142,801, 

CC(=O)N(C)C1(CCN(CC1)CCC[C@@]2(CCCN(C2)C(=O)C3=CC=CC=C3)C4=CC(=C(C=C4)Cl)Cl)C5=CC=CC=C5

LINK

http://drugapprovalsint.com/

http://drugapprovalsint.com/

http://drugapprovalsint.com/

http://drugapprovalsint.com/

/////////////

ACT-334441

Cenerimod

UNII-Y333RS1786; Y333RS1786

S1P receptor 1 agonist

CAS 1262414-04-9
Chemical Formula: C25H31N3O5
Exact Mass: 453.22637

Actelion Pharmaceuticals Ltd.

Martin Bolli, Cyrille Lescop, Boris Mathys,Keith Morrison, Claus Mueller, Oliver Nayler,Beat Steiner,

(S)-3-(4-(5-(2-cyclopentyl-6-methoxypyridin-4-yl)-1,2,4-oxadiazol-3-yl)-2-ethyl-6-methylphenoxy)propane-1,2-diol

(2S)-3-[4-[5-(2-cyclopentyl-6-methoxypyridin-4-yl)-1,2,4-oxadiazol-3-yl]-2-ethyl-6-methylphenoxy]propane-1,2-diol

(S)-3-{4-[5-(2-Cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol

Cenerimod is a potent and orally active immunomodulator, exhibited EC50 value of 2.7 nM. Cenerimod is an agonist for the G protein-coupled receptor S1 P1/EDG1 and has a powerful and long-lasting immunomodulating effect which is achieved by reducing the number of circulating and infiltrating T- and B-lymphocytes, without affecting their maturation, memory, or expansion. Cenerimod may be useful for prevention or treatment of diseases associated with an activated immune system

CENERIMOD

ACT-334441; lysosphingolipid receptor agonist – Actelion; S1P₁ receptor modulator – Actelion; Second selective S1P1 receptor agonist – Actelion; Sphingosine 1 phosphate receptor modulators – Actelion; Sphingosine 1-phosphate receptor 1 agonists – Actelion

• Mechanism of Action Lysosphingolipid receptor agonists

• Highest Development Phases

• Phase I/II Systemic lupus erythematosus

Most Recent Events

• 09 Jun 2016 Actelion terminates a phase I drug interaction trial for Systemic lupus erythematosus (In volunteers) in France (NCT02479204)
• 22 Dec 2015 Phase-I/II clinical trials in Systemic lupus erythematosus in Ukraine, Belarus (PO) (NCT02472795)
• 24 Sep 2015 Phase-I/II clinical trials in Systemic lupus erythematosus in USA (PO) (NCT02472795)

The human immune system is designed to defend the body against foreign micro-organisms and substances that cause infection or disease. Complex regulatory mechanisms ensure that the immune response is targeted against the intruding substance or organism and not against the host. In some cases, these control mechanisms are unregulated and autoimmune responses can develop. A consequence of the uncontrolled inflammatory response is severe organ, cell, tissue or joint damage. With current treatment, the whole immune system is usually suppressed and the body’s ability to react to infections is also severely compromised. Typical drugs in this class include azathioprine, chlorambucil, cyclophosphamide, cyclosporin, or methotrexate. Corticosteroids which reduce inflammation and suppress the immune response, may cause side effects when used in long term treatment. Nonsteroidal anti-inflammatory drugs (NSAIDs) can reduce pain and inflammation, however, they exhibit considerable side effects. Alternative treatments include agents that activate or block cytokine signaling.

Orally active compounds with immunomodulating properties, without compromising immune responses and with reduced side effects would significantly improve current treatments of uncontrolled inflammatory diseases.

In the field of organ transplantation the host immune response must be suppressed to prevent organ rejection. Organ transplant recipients can experience some rejection even when they are taking immunosuppressive drugs. Rejection occurs most frequently in the first few weeks after transplantation, but rejection episodes can also happen months or even years after transplantation. Combinations of up to three or four medications are commonly used to give maximum protection against rejection while minimizing side effects. Current standard drugs used to treat the rejection of transplanted organs interfere with discrete intracellular pathways in the activation of T-type or B-type white blood cells. Examples of such drugs are cyclosporin, daclizumab, basiliximab, everolimus, or FK506, which interfere with cytokine release or signaling; azathioprine or leflunomide, which inhibit nucleotide synthesis; or 15-deoxyspergualin, an inhibitor of leukocyte differentiation.

The beneficial effects of broad immunosuppressive therapies relate to their effects; however, the generalized immunosuppression which these drugs produce diminishes the immune system’s defense against infection and malignancies. Furthermore, standard immunosuppressive drugs are often used at high dosages and can cause or accelerate organ damage.

SYNTHESIS

PATENT

https://www.google.com/patents/WO2011007324A1?cl=zh

The human immune system is designed to defend the body against foreign microorganisms and substances that cause infection or disease. Complex regulatory mechanisms ensure that the immune response is targeted against the intruding substance or organism and not against the host. In some cases, these control mechanisms are unregulated and autoimmune responses can develop. A consequence of the uncontrolled inflammatory response is severe organ, cell, tissue or joint damage. With current treatment, the whole immune system is usually suppressed and the body’s ability to react to infections is also severely compromised. Typical drugs in this class include azathioprine, chlorambucil, cyclophosphamide, cyclosporin, or methotrexate. Corticosteroids which reduce inflammation and suppress the immune response, may cause side effects when used in long term treatment. Nonsteroidal anti-inflammatory drugs (NSAIDs) can reduce pain and inflammation, however, they exhibit considerable side effects. Alternative treatments include agents that activate or block cytokine signaling.

Orally active compounds with immunomodulating properties, without compromising immune responses and with reduced side effects would significantly improve current treatments of uncontrolled inflammatory diseases.

In the field of organ transplantation the host immune response must be suppressed to prevent organ rejection. Organ transplant recipients can experience some rejection even when they are taking immunosuppressive drugs. Rejection occurs most frequently in the first few weeks after transplantation, but rejection episodes can also happen months or even years after transplantation. Combinations of up to three or four medications are commonly used to give maximum protection against rejection while minimizing side effects. Current standard drugs used to treat the rejection of transplanted organs interfere with discrete intracellular pathways in the activation of T-type or B-type white blood cells. Examples of such drugs are cyclosporin, daclizumab, basiliximab, everolimus, or FK506, which interfere with cytokine release or signaling; azathioprine or leflunomide, which inhibit nucleotide synthesis; or 15-deoxyspergualin, an inhibitor of leukocyte differentiation.

The beneficial effects of broad immunosuppressive therapies relate to their effects; however, the generalized immunosuppression which these drugs produce diminishes the immune system’s defense against infection and malignancies. Furthermore, standard immunosuppressive drugs are often used at high dosages and can cause or accelerate organ damage.

Description of the invention

The present invention provides novel compounds of Formula (I) that are agonists for the G protein-coupled receptor S1 P1/EDG1 and have a powerful and long-lasting immunomodulating effect which is achieved by reducing the number of circulating and infiltrating T- and B-lymphocytes, without affecting their maturation, memory, or expansion. The reduction of circulating T- / B-lymphocytes as a result of S1 P1/EDG1 agonism, possibly in combination with the observed improvement of endothelial cell layer function associated with S1 P1/EDG1 activation, makes such compounds useful to treat uncontrolled inflammatory diseases and to improve vascular functionality. Prior art document WO 2008/029371 discloses compounds that act as S1 P1/EDG1 receptor agonists and show an immunomodulating effect as described above. Unexpectedly, it has been found that the compounds of the present invention have a reduced potential to constrict airway tissue/vessels when compared to compounds of the prior art document WO 2008/029371. The compounds of the present invention therefore demonstrate superiority with respect to their safety profile, e.g. a lower risk of bronchoconstriction.

Examples of WO 2008/029371 , which are considered closest prior art analogues are shown in Figure 1.

Figure 1 : Structure of Examples of prior art document WO 2008/029371 , which are considered closest analogues to the compounds of the present invention.

The data on the constriction of rat trachea rings compiled in Table 1 illustrate the superiority of the compounds of the present invention as compared to compounds of prior art document WO 2008/029371.

For instance, the compounds of Example 1 and 6 of the present invention show a significantly reduced potential to constrict rat trachea rings when compared to the compounds of prior art Examples 222 and 226 of WO 2008/029371 , respectively. Furthermore, the compounds of Example 1 and 6 of the present invention also show a reduced potential to constrict rat trachea rings when compared to the compounds of prior art Examples 196 and 204 of WO 2008/029371 , respectively. These data demonstrate that compounds wherein R¹ represents 3-pentyl and R² represents methoxy are superior compared to the closest prior art compounds of WO 2008/029371 , i.e. the compounds wherein R¹ represents an isobutyl and R² represents methoxy or wherein R¹represents methyl and R² represents 3-pentyl. Moreover, also the compound of Example 16 of the present invention, wherein R¹ is 3-methyl-but-1-yl and R² is methoxy, exhibits a markedly reduced potential to constrict rat trachea rings when compared to its closest analogue prior art Example 226 of WO 2008/029371 wherein R¹ is isobutyl and R² is methoxy.

The unexpected superiority of the compounds of the present invention is also evident from the observation that the compounds of Example 2 and 7 of the present invention show a markedly reduced potential to constrict rat trachea rings when compared to the compounds of prior art Examples 229 and 233 of WO 2008/029371 , respectively. This proves that compounds wherein R¹represents cyclopentyl and R² represents methoxy are superior compared to the closest prior art compounds of WO 2008/029371 , i.e. the compounds wherein R¹ represents methyl and R² represents cyclopentyl.

Also, the compound of Example 3 of the present invention exhibits the same low potential to constrict rat trachea rings as its S-enantiomer, i.e. the compound of Example 2 of the present invention, indicating that the configuration at this position has no significant effect on trachea constriction. Furthermore, also Example 21 of the present invention exhibits the same low potential to constrict rat trachea rings as present Example 2, which differs from Example 21 only by the linker A (forming a 5-pyridin-4-yl-[1 ,2,4]oxadiazole instead of a 3- pyridin-4-yl-[1 ,2,4]oxadiazole). This indicates that also the nature of the oxadiazole is not critical regarding trachea constriction.

Table 1 : Rat trachea constriction in % of the constriction induced by 50 mM KCI. n.d. = not determined. For experimental details and further data see Example 33.

result obtained at a compound concentration of 300 nM.

The compounds of the present invention can be utilized alone or in combination with standard drugs inhibiting T-cell activation, to provide a new immunomodulating therapy with a reduced propensity for infections when compared to standard immunosuppressive therapy. Furthermore, the compounds of the present invention can be used in combination with reduced dosages of traditional immunosuppressant therapies, to provide on the one hand effective immunomodulating activity, while on the other hand reducing end organ damage associated with higher doses of standard immunosuppressive drugs. The observation of improved endothelial cell layer function associated with S1 P1/EDG1 activation provides additional benefits of compounds to improve vascular function.

The nucleotide sequence and the amino acid sequence for the human S1 P1/EDG1 receptor are known in the art and are published in e.g.: HIa, T., and Maciag, T., J. Biol

Chem. 265 (1990), 9308-9313; WO 91/15583 published 17 October 1991 ; WO 99/46277 published 16 September 1999. The potency and efficacy of the compounds of Formula (I) are assessed using a GTPγS assay to determine EC₅O values and by measuring the circulating lymphocytes in the rat after oral administration, respectively (see in experimental part). i) In a first embodiment, the invention relates to pyridine compounds of the Formula (I),

Formula (I)

PATENT

WO 2013175397

https://www.google.com/patents/WO2013175397A1?cl=en

Pyridine-4-yl derivatives of formula (PD),

Formula (PD) A represents

(the asterisks indicate the bond that is linked to the pyridine group of Formula (PD));

R^a represents 3-pentyl, 3-methyl-but-1-yl, cyclopentyl, or cyclohexyl;

R^b represents methoxy;

R^c represents 2,3-dihydroxypropoxy, -OCH₂-CH(OH)-CH₂-NHCO-CH₂OH,

-OCH₂-CH(OH)-CH₂N(CH₃)-CO-CH₂OH, -NHS0₂CH₃, or -NHS0₂CH₂CH₃; and

R^d represents ethyl or chloro.)

disclosed in WO201 1007324, have immunomodulating activity through their S1 P1/EDG1 receptor agonistic activity. Therefore, those pyridine-4-yl derivatives are useful for prevention and / or treatment of diseases or disorders associated with an activated immune system, including rejection of transplanted organs such as kidney, liver, heart, lung, pancreas, cornea, and skin; graft-versus-host diseases brought about by stem cell transplantation; autoimmune syndromes including rheumatoid arthritis, multiple sclerosis, inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis, psoriasis, psoriatic arthritis, thyroiditis such as Hashimoto’s thyroiditis, uveo-retinitis; atopic diseases such as rhinitis, conjunctivitis, dermatitis; asthma; type I diabetes; post-infectious autoimmune diseases including rheumatic fever and post-infectious glomerulonephritis; solid cancers and tumor metastasis. 2-Cyclopentyl-6-methoxy-isonicotinic acid, which is also disclosed in WO201 1007324, is a useful intermediate for the synthesis of the pyridine-4-yl derivatives of formula (PD), wherein R^a is a cyclopentyl group.

In the process described in WO201 1007324, 2-cyclopentyl-6-methoxy-isonicotinic acid was prepared according to the following reaction scheme 1 :

Compound D Compound E

Rieke Zinc: cyclopentylzinc bromide;

PdCI₂(dppf)dcm: 1 ,1 ‘-Bis(diphenylphosphino)ferrocene-palladium(ll)dichloride

dichloromethane complex

However, the abovementioned process has drawbacks for larger scale, i.e. industrial scale synthesis of 2-cyclopentyl-6-methoxy-isonicotinic acid, for the following reasons:

a) The commercially available starting material, 2,6-dichloro-isonicotinic acid (Compound A) is expensive.

b) The conversion of Compound C to Compound D is cost-intensive. The reaction has to be performed under protective atmosphere with expensive palladium catalysts and highly reactive and expensive Rieke zinc complex. Such synthesis steps are expensive to scale up and it was therefore highly desired to find alternative synthesis methods.

Even though Goldsworthy, J. Chem. Soc. 1934, 377-378 discloses the preparation of 1 -cyclopentylethanone, which is a key building block in the new process of the present invention, by using ethyl 1 -acetoacetate as a starting material, this synthesis was far from being suitable in an industrial process. The reported yield was low (see also under “Referential Examples” below). Scheme 2

ethyl 1 -acetylcyclo- 1-cyclopentyl- pentanecarboxylate ethanone

Besides the early work by Goldsworthy there are several recent examples for the preparation of 1 -cyclopentylethanone described in the literature. Such examples include:

1 ) Addition of methyl lithium to a N-cyclopentanecarbonyl-N,0-dimethylhydroxylamine at -78°C in a yield of 77%. US2006/199853 A1 , 2006 and US2006/223884 A1 , 2006.

2) Addition of methyl lithium to a cyclopentyl carboxylic acid in diethylether at -78°C in a yield of 81 %. J. Am. Chem. Soc, 1983, 105, 4008-4017.

3) Addition of methylmagnesiumbromide to cyclopentanecarbonitrile.

Bull. Soc. Chim. Fr., 1967, 3722-3729.

4) Oxidation of 1 -cyclopentylethanol with chromtrioxide. US5001 140 A1 , 1991.

WO2009/71707 A1 , 2009.

5) Addition of cyclopentylmagnesium bromide to acetic anhydride at -78 °C with a yield of 54%. WO2004/74270 A2, 2004.

6) Synthesis of 1-cyclopentylethanone in 5 steps from cyclopentanone. Zhang, Pang; Li, Lian-chu, Synth. Commun., 1986, 16, 957-966.

However, the processes described in the above-listed publications are not efficient for scale-up since they require cryogenic temperatures, expensive starting materials, toxic reagents or many steps. The lack of an efficient process to manufacture 1 -cyclopentylethanone is further also mirrored by the difficulty in sourcing this compound on kilogram scale for a reasonable price and delivery time. Therefore, the purpose of the present invention is to provide a new, efficient and cost effective process for the preparation of 2-cyclopentyl-6-methoxy-isonicotinic acid, which is suitable for industrial scale synthesis.

Patent

https://patentscope.wipo.int/search/en/detail.jsf?docId=US133347630&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCTDescription

Disclosed in WO2011007324, have immunomodulating activity through their S1P1/EDG1 receptor agonistic activity. Therefore, those pyridine-4-yl derivatives are useful for prevention and/or treatment of diseases or disorders associated with an activated immune system, including rejection of transplanted organs such as kidney, liver, heart, lung, pancreas, cornea, and skin; graft-versus-host diseases brought about by stem cell transplantation; autoimmune syndromes including rheumatoid arthritis, multiple sclerosis, inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis, psoriasis, psoriatic arthritis, thyroiditis such as Hashimoto’s thyroiditis, uveo-retinitis; atopic diseases such as rhinitis, conjunctivitis, dermatitis; asthma; type I diabetes; post-infectious autoimmune diseases including rheumatic fever and post-infectious glomerulonephritis; solid cancers and tumor metastasis. 2-Cyclopentyl-6-methoxy-isonicotinic acid, which is also disclosed in WO2011007324, is a useful intermediate for the synthesis of the pyridine-4-yl derivatives of formula (PD), wherein R^a is a cyclopentyl group.

Rieke Zinc: cyclopentylzinc bromide;
PdCl₂(dppf)dcm: 1,1′-Bis(diphenylphosphino)ferrocene-palladium(II)dichloride dichloromethane complex

EXAMPLES

Example 1a

1-Cyclopentylethanone

Example 1 b

1-Cyclopentylethanone

Example 1c

1-Cyclopentylethanone

Example 1d

1-Cyclopentylethanone

Example 1e

1-Cyclopentylethanone

Example 1f

Tert-butyl 1-acetylcyclopentanecarboxylate

Example 1 g

Tert-butyl 1-acetylcyclopentanecarboxylate

Example 2

2-Cyclopentyl-6-hydroxyisonicotinic acid

Example 3

Methyl 2-cyclopentyl-6-hydroxyisonicotinate

Example 4a

Methyl 2-chloro-6-cyclopentylisonicotinate

Example 4b

Methyl 2-chloro-6-cyclopentylisonicotinate

Example 5

2-Cyclopentyl-6-methoxyisonicotinic acid

Example 6

Ethyl 4-cyclopentyl-2,4-dioxobutanoate

Example 7

Ethyl 3-cyano-6-cyclopentyl-2-hydroxyisonicotinate

REFERENTIAL EXAMPLES

Referential Example 1

Referential Example 2

PATENT

US8658675

https://www.google.com/patents/US8658675

Martin Bolli, Cyrille Lescop, Boris Mathys,Keith Morrison, Claus Mueller, Oliver Nayler,Beat Steiner,

novel compounds of Formula (I) that are agonists for the G protein-coupled receptor S1P1/EDG1 and have a powerful and long-lasting immunomodulating effect which is achieved by reducing the number of circulating and infiltrating T- and B-lymphocytes, without affecting their maturation, memory, or expansion. The reduction of circulating T-/B-lymphocytes as a result of S1P1/EDG1 agonism, possibly in combination with the observed improvement of endothelial cell layer function associated with S1P1/EDG1 activation, makes such compounds useful to treat uncontrolled inflammatory diseases and to improve vascular functionality. Prior art document WO 2008/029371 discloses compounds that act as S1P1/EDG1 receptor agonists and show an immunomodulating effect as described above. Unexpectedly, it has been found that the compounds of the present invention have a reduced potential to constrict airway tissue/vessels when compared to compounds of the prior art document WO 2008/029371. The compounds of the present invention therefore demonstrate superiority with respect to their safety profile, e.g. a lower risk of bronchoconstriction.

Examples of WO 2008/029371, which are considered closest prior art analogues are shown in FIG. 1.

The data on the constriction of rat trachea rings compiled in Table 1 illustrate the superiority of the compounds of the present invention as compared to compounds of prior art document WO 2008/029371.

For instance, the compounds of Example 1 and 6 of the present invention show a significantly reduced potential to constrict rat trachea rings when compared to the compounds of prior art Examples 222 and 226 of WO 2008/029371, respectively. Furthermore, the compounds of Example 1 and 6 of the present invention also show a reduced potential to constrict rat trachea rings when compared to the compounds of prior art Examples 196 and 204 of WO 2008/029371, respectively. These data demonstrate that compounds wherein R¹ represents 3-pentyl and R²represents methoxy are superior compared to the closest prior art compounds of WO 2008/029371, i.e. the compounds wherein R¹ represents an isobutyl and R²represents methoxy or wherein R¹ represents methyl and R² represents 3-pentyl. Moreover, also the compound of Example 16 of the present invention, wherein R¹is 3-methyl-but-1-yl and R² is methoxy, exhibits a markedly reduced potential to constrict rat trachea rings when compared to its closest analogue prior art Example 226 of WO 2008/029371 wherein R¹ is isobutyl and R² is methoxy.

The unexpected superiority of the compounds of the present invention is also evident from the observation that the compounds of Example 2 and 7 of the present invention show a markedly reduced potential to constrict rat trachea rings when compared to the compounds of prior art Examples 229 and 233 of WO 2008/029371, respectively. This proves that compounds wherein R¹ represents cyclopentyl and R² represents methoxy are superior compared to the closest prior art compounds of WO 2008/029371, i.e. the compounds wherein R¹represents methyl and R² represents cyclopentyl.

Preparation of Intermediates2-Chloro-6-methyl-isonicotinic acid

The title compound and its ethyl ester are commercially available.

2-(1-Ethyl-propyl)-6-methoxy-isonicotinic acid

a) To a solution of 2,6-dichloroisonicotinic acid (200 g, 1.04 mol) in methanol (3 L), 32% aq. NaOH (770 mL) is added. The stirred mixture becomes warm (34° C.) and is then heated to 70° C. for 4 h before it is cooled to rt. The mixture is neutralised by adding 32% aq. HCl (100 mL) and 25% aq. HCl (700 mL). The mixture is stirred at rt overnight. The white precipitate that forms is collected, washed with methanol and dried. The filtrate is evaporated and the residue is suspended in water (200 mL). The resulting mixture is heated to 60° C. Solid material is collected, washed with water and dried. The combined crops give 2-chloro-6-methoxy-isonicotinic acid (183 g) as a white solid; LC-MS: t_R=0.80 min, [M+1]⁺=187.93.

b) To a suspension of 2-chloro-6-methoxy-isonicotinic acid (244 g, 1.30 mol) in methanol (2.5 L), H₂SO₄ (20 mL) is added. The mixture is stirred at reflux for 24 h before it is cooled to 0° C. The solid material is collected, washed with methanol (200 mL) and water (500 mL) and dried under HV to give 2-chloro-6-methoxy-isonicotinic acid methyl ester (165 g) as a white solid; LC-MS: t_R=0.94 min, [M+1]⁺=201.89.

c) Under argon, Pd(dppf) (3.04 g, 4 mmol) is added to a solution of 2-chloro-6-methoxy-isonicotinic acid methyl ester (50 g, 0.248 mol) in THF (100 mL). A 0.5 M solution of 3-pentylzincbromide in THF (550 mL) is added via dropping funnel. Upon complete addition, the mixture is heated to 85° C. for 18 h before it is cooled to rt. Water (5 mL) is added and the mixture is concentrated. The crude product is purified by filtration over silica gel (350 g) using heptane:EA 7:3 to give 2-(1-ethyl-propyl)-6-methoxy-isonicotinic acid methyl ester (53 g) as a pale yellow oil; ¹H NMR (CDCl₃): δ0.79 (t, J=7.5 Hz, 6H), 1.63-1.81 (m, 4H), 2.47-2.56 (m, 1H), 3.94 (s, 3H), 3.96 (s, 3H), 7.12 (d, J=1.0 Hz, 1H), 7.23 (d, J=1.0 Hz, 1H).

d) A solution of 2-(1-ethyl-propyl)-6-methoxy-isonicotinic acid methyl ester (50 g, 0.211 mol) in ethanol (250 mL), water (50 mL) and 32% aq. NaOH (50 mL) is stirred at 80° C. for 1 h. The mixture is concentrated and the residue is dissolved in water (200 mL) and extracted with TBME. The org. phase is separated and washed once with water (200 mL). The TBME phase is discarded. The combined aq. phases are acidified by adding 25% aq. HCl and then extracted with EA (400+200 mL). The combined org. extracts are concentrated. Water (550 mL) is added to the remaining residue. The mixture is heated to 70° C., cooled to rt and the precipitate that forms is collected and dried to give the title compound (40.2 g) as a white solid; LC-MS: t_R=0.95 min, [M+1]⁺=224.04; ¹H NMR (D₆-DMSO): δ 0.73 (t, J=7.3 Hz, 6H), 1.59-1.72 (m, 4H), 2.52-2.58 (m, 1H), 3.88 (s, 3H), 7.00 (d, J=1.0 Hz, 1H), 7.20 (d, J=1.0 Hz, 1H).

2-Methoxy-6-(3-methyl-butyl)-isonicotinic acid

The title compound is prepared in analogy to 2-(1-ethyl-propyl)-6-methoxy-isonicotinic acid; LC-MS: t_R=0.94 min, [M+1]⁺=224.05; ¹H NMR (D₆-DMSO): δ 0.92 (d, J=5.8 Hz, 6H), 1.54-1.62 (m, 3H), 2.70-2.76 (m, 2H), 3.88 (s, 3H), 6.99 (s, 1H), 7.25 (s, 1H), 13.52 (s).

2-Cyclopentyl-6-methoxy-isonicotinic acid

The title compound is prepared in analogy to 2-(1-ethyl-propyl)-6-methoxy-isonicotinic acid; LC-MS: t_R=0.93 min, [M+1]⁺=222.02; ¹H NMR (CDCl₃): δ 1.68-1.77 (m, 2H), 1.81-1.90 (m, 4H), 2.03-2.12 (m, 2H), 3.15-3.25 (m, 1H), 3.99 (s, 3H), 7.18 (d, J=1.0 Hz, 1H), 7.35 (d, J=0.8 Hz, 1H).

2-Cyclohexyl-6-methoxy-isonicotinic acid

The title compound is prepared in analogy to 2-(1-ethyl-propyl)-6-methoxy-isonicotinic acid; LC-MS: t_R=0.98 min, [M+1]⁺=236.01; ¹H NMR (D₆-DMSO): δ 1.17-1.29 (m, 1H), 1.31-1.43 (m, 2H), 1.44-1.55 (m, 2H), 1.67-1.73 (m, 1H), 1.76-1.83 (m, 2H), 1.84-1.92 (m, 2H), 2.66 (tt, J=11.3, 3.3 Hz, 1H), 3.88 (s, 3H), 7.00 (d, J=1.0 Hz, 1H), 7.23 (d, J=1.0 Hz, 1H).

2-Cyclopentyl-N-hydroxy-6-methoxy-isonicotinamidine

a) A solution of 2-cyclopentyl-6-methoxy-isonicotinic acid methyl ester (3.19 g, 13.6 mmol) in 7 N NH₃ in methanol (50 mL) is stirred at 60° C. for 18 h. The solvent is removed in vacuo and the residue is dried under HV to give crude 2-cyclopentyl-6-methoxy-isonicotinamide (3.35 g) as a pale yellow solid; LC-MS**: t_R=0.57 min, [M+1]⁺=221.38.

b) Pyridine (8.86 g, 91.3 mmol) is added to a solution of 2-cyclopentyl-6-methoxy-isonicotinamide (3.35 g, 15.2 mmol) in DCM (100 mL). The mixture is cooled to 0° C. before trifluoroacetic acid anhydride (9.58 g, 45.6 mmol) is added portionwise. The mixture is stirred at 0° C. for 1 h before it is diluted with DCM (100 mL) and washed with sat. aq. NaHCO₃ solution (100 mL) and brine (100 mL). The separated org. phase is dried over MgSO₄, filtered and concentrated. The crude product is purified by CC on silica gel eluting with heptane:EA 9:1 to give 2-cyclopentyl-6-methoxy-isonicotinonitrile (2.09 g) as pale yellow oil; LC-MS**: t_R=0.80 min, [M+1]⁺=not detectable; ¹H NMR (D₆-DMSO): δ 1.61-1.82 (m, 6H), 1.94-2.03 (m, 2H), 3.16 (quint, J=7.8 Hz, 1H), 3.89 (s, 3H), 7.15 (s, 1H), 7.28 (s, 1H).

c) To a solution of 2-cyclopentyl-6-methoxy-isonicotinonitrile (2.09 g, 10.3 mmol) in methanol (100 mL), hydroxylamine hydrochloride (2.15 g, 31.0 mmol) and NaHCO₃ (3.04 g, 36.2 mmol) are added. The mixture is stirred at 60° C. for 18 h before it is filtered and the filtrate is concentrated. The residue is dissolved in EA (300 mL) and washed with water (30 mL). The washings are extracted back with EA (4×100 mL) and DCM (4×100 mL). The combined org. extracts are dried over MgSO₄, filtered, concentrated and dried under HV to give the title compound (2.74 g) as a white solid; LC-MS**: t_R=0.47 min, [M+1]⁺=236.24; ¹H NMR (D₆-DMSO): δ 1.61-1.82 (m, 6H), 1.92-2.01 (m, 2H), 3.04-3.13 (m, 1H), 3.84 (s, 3H), 5.90 (s, 2H), 6.86 (s, 1H), 7.13 (s, 1H), 9.91 (s, 1H).

2-Cyclopentyl-6-methoxy-isonicotinic acid hydrazide

a) To a solution of 2-cyclopentyl-6-methoxy-isonicotinic acid (2.00 g, 9.04 mmol), hydrazinecarboxylic acid benzyl ester (1.50 g, 9.04 mmol) and DIPEA (2.34 g, 18.1 mmol) in DCM (40 mL), TBTU (3.19 g, 9.94 mmol) is added. The mixture is stirred at rt for 2 h before it is diluted with EA (250 mL), washed twice with sat. aq. NaHCO₃ solution (150 mL) followed by brine (100 mL), dried over MgSO₄, filtered and concentrated. The crude product is purified by CC on silica gel eluting with heptane:EA 4:1 to give N′-(2-cyclopentyl-6-methoxy-pyridine-4-carbonyl)-hydrazinecarboxylic acid benzyl ester (2.74 g) as pale yellow oil; LC-MS**: t_R=0.74 min, [M+1]⁺=369.69; ¹H NMR (D₆-DMSO): δ 1.62-1.83 (m, 6H), 1.95-2.05 (m, 2H), 3.10-3.21 (m, 1H), 3.88 (s, 3H), 5.13 (s, 2H), 6.97 (s, 1H), 7.23 (s, 1H), 7.28-7.40 (m, 5H), 9.45 (s, 1H), 10.52 (s, 1H).

b) Pd/C (500 mg, 10% Pd) is added to a solution of N′-(2-cyclopentyl-6-methoxy-pyridine-4-carbonyl)-hydrazinecarboxylic acid benzyl ester (2.74 g, 7.42 mmol) in THF (50 mL) and methanol (50 mL). The mixture is stirred at rt under 1 bar of H₂ for 25 h. The catalyst is removed by filtration and the filtrate is concentrated and dried under HV to give the title compound (1.58 g) as an off-white solid; LC-MS**: t_R=0.51 min, [M+1]⁺=236.20; ¹H NMR (D₆-DMSO): δ 1.60-1.82 (m, 6H), 1.94-2.03 (m, 2H), 3.08-3.19 (m, 1H), 3.86 (s, 3H), 4.56 (s br, 2H), 6.93 (d, J=1.0 Hz, 1H), 7.20 (d, J=1.0 Hz, 1H), 9.94 (s, 1H).

3-Ethyl-4-hydroxy-5-methyl-benzonitrile

The title compound is prepared from 3-ethyl-4-hydroxy-5-methyl-benzaldehyde following literature procedures (A. K. Chakraborti, G. Kaur, Tetrahedron 55 (1999) 13265-13268); LC-MS: t_R=0.90 min; ¹H NMR (CDCl₃): δ1.24 (t, J=7.6 Hz, 3H), 2.26 (s, 3H), 2.63 (q, J=7.6 Hz, 2H), 5.19 (s, 1H), 7.30 (s, 2H).

3-Chloro-4-hydroxy-5-methyl-benzonitrile

The title compound is prepared from commercially available 2-chloro-6-methyl-phenol in analogy to literature procedures (see 3-ethyl-4-hydroxy-5-methyl-benzonitrile); LC-MS: t_R=0.85 min. ¹H NMR (CDCl₃): δ2.33 (s, 3H), 6.10 (s, 1H), 7.38 (s, 1H), 7.53 (d, J=1.8 Hz, 1H).

3-Ethyl-4,N-dihydroxy-5-methyl-benzamidine

The title compound is prepared from 3-ethyl-4-hydroxy-5-methyl-benzonitrile or from commercially available 2-ethyl-6-methyl-phenol following literature procedures (G. Trapani, A. Latrofa, M. Franco, C. Altomare, E. Sanna, M. Usala, G. Biggio, G. Liso, J. Med. Chem. 41 (1998) 1846-1854; A. K. Chakraborti, G. Kaur, Tetrahedron 55 (1999) 13265-13268; E. Meyer, A. C. Joussef, H. Gallardo, Synthesis 2003, 899-905); LC-MS: t_R=0.55 min; ¹H NMR (D₆-DMSO): δ 9.25 (s br, 1H), 7.21 (s, 2H), 5.56 (s, 2H), 2.55 (q, J=7.6 Hz, 2H), 2.15 (s, 3H), 1.10 (t, J=7.6 Hz, 3H).

3-Chloro-4,N-dihydroxy-5-methyl-benzamidine

The title compound is prepared from commercially available 2-chloro-6-methyl-phenol in analogy to literature procedures (e.g. B. Roth et al. J. Med. Chem. 31 (1988) 122-129; and literature cited for 3-ethyl-4,N-dihydroxy-5-methyl-benzamidine); 3-chloro-4-hydroxy-5-methyl-benzaldehyde: LC-MS: t_R=0.49 min, [M+1]⁺=201.00; ¹H NMR 82.24 (s, 2H), 2.35 (s, 4H), 5.98 (s br, 1H), 7.59 (d, J=1.8 Hz, 1H), 7.73 (d, J=1.8 Hz, 1H), 9.80 (s, 1H); 3-chloro-4,N-dihydroxy-5-methyl-benzamidine: ¹H NMR (D₆-DMSO): δ 2.21 (s, 3H), 5.72 (s br, 2H), 7.40 (s, 1H), 7.48 (s, 1H), 9.29 (s br, 1H), 9.48 (s br, 1H).

(R)-4-(2,2-Dimethyl-[1,3]dioxolan-4-ylmethoxy)-3-ethyl-N-hydroxy-5-methyl-benzamidine

a) To a solution of 3-ethyl-4-hydroxy-5-methyl-benzonitrile (2.89 g, 17.9 mmol) in THF (80 mL), (R)-(2,2-dimethyl-[1,3]dioxolan-4-yl)methanol (2.84 g, 21.5 mmol) followed by triphenylphosphine (5.81 g, 21.5 mmol) is added. The mixture is cooled with an ice-bath before DEAD (9.36 g, 21.5 mmol) is added dropwise. The mixture is stirred at rt for 1 h, the solvent is removed in vacuo and the residue is purified by CC on silica gel eluting with heptane:EA 85:15 to give (R)-4-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-3-ethyl-5-methyl-benzonitrile (4.45 g) as a pale yellow oil; LC-MS**: t_R=0.75 min, [M+1]⁺=not detected; ¹H NMR (CDCl₃): δ1.25 (t, J=7.5 Hz, 3H), 1.44 (s, 3H), 1.49 (s, 3H), 2.34 (s, 3H), 2.65-2.77 (m, 2H), 3.80-3.90 (m, 2H), 3.94-4.00 (m, 1H), 4.21 (t, J=7.3 Hz, 1H), 4.52 (quint, J=5.8 Hz, 1H), 7.35 (s, 1H), 7.38 (s, 1H).

b) To a mixture of (R)-4-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-3-ethyl-5-methyl-benzonitrile (4.45 g, 16.2 mmol) and NaHCO₃ (4.75 g, 56.6 mmol) in methanol (30 mL), hydroxylamine hydrochloride (3.37 g, 48.5 mmol) is added. The mixture is stirred at 60° C. for 18 h before it is filtered and the solvent of the filtrate is removed in vacuo. The residue is dissolved in EA and washed with a small amount of water and brine. The org. phase is separated, dried over MgSO₄, filtered, concentrated and dried to give the title compound (5.38 g) as a white solid; LC-MS**: t_R=0.46 min, [M+1]⁺=309.23; ¹H NMR (D₆-DMSO): δ 1.17 (t, J=7.5 Hz, 3H), 1.33 (s, 3H), 1.38 (s, 3H), 2.25 (s, 3H), 2.57-2.69 (m, 2H), 3.73-3.84 (m, 3H), 4.12 (t, J=7.0 Hz, 1H), 4.39-4.45 (m, 1H), 5.76 (s br, 2H), 7.34 (s, 1H), 7.36 (s, 1H), 9.47 (s, 1H).

(R)-3-Chloro-4-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-N-hydroxy-5-methyl-benzamidine

The title compound is obtained as a colorless oil (1.39 g) in analogy to (R)-4-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-3-ethyl-N-hydroxy-5-methyl-benzamidine starting from 3-chloro-4-hydroxy-5-methyl-benzonitrile and L-α,β-isopropyliden glycerol; LC-MS: t_R=0.66 min, [M+H]⁺=314.96.

(S)-4-(3-Amino-2-hydroxypropoxy)-3-ethyl-5-methylbenzonitrile

a) To a solution of 3-ethyl-4-hydroxy-5-methyl-benzonitrile (5.06 g, 31.4 mmol) in THF (80 mL), PPh₃ (9.06 g, 34.5 mmol) and (R)-glycidol (2.29 mL, 34.5 mmol) are added. The mixture is cooled to 0° C. before DEAD in toluene (15.8 mL, 34.5 mmol) is added. The mixture is stirred for 18 h while warming up to rt. The solvent is evaporated and the crude product is purified by CC on silica gel eluting with heptane:EA 7:3 to give 3-ethyl-5-methyl-4-oxiranylmethoxy-benzonitrile (5.85 g) as a yellow oil; LC-MS: t_R=0.96 min; [M+42]⁺=259.08.

b) The above epoxide is dissolved in 7 N NH₃ in methanol (250 mL) and the solution is stirred at 65° C. for 18 h. The solvent is evaporated to give crude (S)-4-(3-amino-2-hydroxypropoxy)-3-ethyl-5-methylbenzonitrile (6.23 g) as a yellow oil; LC-MS: t_R=0.66 min; [M+1]⁺=235.11.

N—((S)-3-[2-Ethyl-4-(N-hydroxycarbamimidoyl)-6-methyl-phenoxy]-2-hydroxy-propyl)-2-hydroxy-acetamide

a) To a solution of (S)-4-(3-amino-2-hydroxypropoxy)-3-ethyl-5-methylbenzonitrile (6.23 g, 26.59 mmol) in THF (150 mL), glycolic acid (2.43 g, 31.9 mmol), HOBt (4.31 g, 31.9 mmol), and EDC hydrochloride (6.12 g, 31.9 mmol) are added. The mixture is stirred at rt for 18 h before it is diluted with sat. aq. NaHCO₃ and extracted twice with EA. The combined org. extracts are dried over MgSO₄, filtered and concentrated. The crude product is purified by CC with DCM containing 8% of methanol to give (S)—N-[3-(4-cyano-2-ethyl-6-methyl-phenoxy)-2-hydroxy-propyl]-2-hydroxy-acetamide (7.03 g) as a yellow oil; LC-MS: t_R=0.74 min, [M+1]⁺=293.10; ¹H NMR (CDCl₃): δ 1.25 (t, J=7.5 Hz, 3H), 2.32 (s, 3H), 2.69 (q, J=7.5 Hz, 2H), 3.48-3.56 (m, 3H), 3.70-3.90 (m, 3H), 4.19 (s, br, 3H), 7.06 (m, 1H), 7.36 (s, 1H), 7.38 (s, 1H).

b) The above nitrile is converted to the N-hydroxy-benzamidine according to literature procedures (e.g. E. Meyer, A. C. Joussef, H. Gallardo, Synthesis 2003, 899-905); LC-MS: t_R=0.51 min, [M+1]⁺=326.13; ¹H NMR (D₆-DMSO): δ 1.17 (t, J=7.4 Hz, 3H), 2.24 (s, 3H), 2.62 (q, J=7.4 Hz, 2H), 3.23 (m, 1H), 3.43 (m, 1H), 3.67 (m, 2H), 3.83 (s, 2H), 3.93 (m, 1H), 5.27 (s br, 1H), 5.58 (s br, 1H), 5.70 (s, 2H), 7.34 (s, 1H), 7.36 (s, 1H), 7.67 (m, 1H), 9.46 (s br, 1H).

(S)—N-(3-[2-Chloro-4-(N-hydroxycarbamimidoyl)-6-methyl-phenoxy]-2-hydroxy-propyl)-2-hydroxy-acetamide

The title compound is obtained as a beige wax (1.1 g) in analogy to N—((S)-3-[2-ethyl-4-(N-hydroxycarbamimidoyl)-6-methyl-phenoxy]-2-hydroxy-propyl)-2-hydroxy-acetamide starting from 3-chloro-4-hydroxy-5-methyl-benzonitrile; LC-MS: t_R=0.48 min, [M+H]⁺=331.94.

3-Chloro-N-hydroxy-4-methanesulfonylamino-5-methyl-benzamidine

a) A mixture of 4-amino-3-chloro-5-methylbenzonitrile (155 mg, 930 μmol) and methanesulfonylchloride (2.13 g, 18.6 mmol, 1.44 mL) is heated under microwave conditions to 150° C. for 7 h. The mixture is cooled to rt, diluted with water and extracted with EA. The org. extract is dried over MgSO₄, filtered and concentrated. The crude product is purified on prep. TLC using heptane:EA 1:1 to give N-(2-chloro-4-cyano-6-methyl-phenyl)-methanesulfonamide (105 mg) as an orange solid; LC-MS**: t_R=0.48 min; ¹H NMR (CDCl₃): δ2.59 (s, 3H), 3.18 (s, 3H), 6.27 (s, 1H), 7.55 (d, J=1.3 Hz, 1H), 7.65 (d, J=1.5 Hz, 1H).

b) Hydroxylamine hydrochloride (60 mg, 858 μmol) and NaHCO₃ (72 mg, 858 μmol) is added to a solution of N-(2-chloro-4-cyano-6-methyl-phenyl)-methanesulfonamide (105 mg, 429 μmol) in methanol (10 mL). The mixture is stirred at 65° C. for 18 h. The solvent is removed in vacuo and the residue is dissolved in a small volume of water (2 mL) and extracted three times with EA (15 mL). The combined org. extracts are dried over MgSO₄, filtered, concentrated and dried to give the title compound (118 mg) as a white solid; LC-MS**: t_R=0.19 min, [M+1]⁺=277.94; ¹H NMR (CDCl₃): δ2.57 (s, 3H), 3.13 (s, 3H), 6.21 (s, 1H), 7.49 (d, J=1.5 Hz, 1H), 7.63 (d, J=1.5 Hz).

3-Ethyl-N-hydroxy-4-methanesulfonylamino-5-methyl-benzamidine

a) In a 2.5 L three-necked round-bottom flask 2-ethyl-6-methyl aniline (250 g, 1.85 mol) is dissolved in DCM (900 mL) and cooled to 5-10° C. Bromine (310.3 g, 1.94 mol) is added over a period of 105 min such as to keep the temperature at 5-15° C. An aq. 32% NaOH solution (275 mL) is added over a period of 10 min to the greenish-grey suspension while keeping the temperature of the reaction mixture below 25° C. DCM (70 mL) and water (100 mL) are added and the phases are separated. The aq. phase is extracted with DCM (250 mL). The combined org. phases are washed with water (300 mL) and concentrated at 50° C. to afford the 4-bromo-2-ethyl-6-methyl-aniline (389 g) as a brown oil; ¹H NMR (CDCl₃): δ 1.27 (t, J=7.3 Hz, 3H), 2.18 (s, 3H), 2.51 (q, J=7.3 Hz, 2H), 3.61 (s br, 1H), 7.09 (s, 2H).

b) A double-jacketed 4 L-flask is charged with 4-bromo-2-ethyl-6-methyl-aniline (324 g, 1.51 mol), sodium cyanide (100.3 g, 1.97 mol), potassium iodide (50.2 g, 0.302 mol) and copper(I)iodide (28.7 g, 0.151 mol). The flask is evacuated three times and refilled with nitrogen. A solution of N,N′-dimethylethylenediamine (191.5 mL, 1.51 mol) in toluene (750 mL) is added. The mixture is heated to 118° C. and stirred at this temperature for 21 h. The mixture is cooled to 93° C. and water (1250 mL) is added to obtain a solution. Ethyl acetate (1250 mL) is added at 22-45° C. and the layers are separated. The org. phase is washed with 10% aq. citric acid (2×500 mL) and water (500 mL). The separated org. phase is evaporated to dryness to afford 4-amino-3-ethyl-5-methyl-benzonitrile (240 g) as a metallic black solid; ¹H NMR (CDCl₃): δ1.29 (t, J=7.5 Hz, 3H), 2.19 (s, 3H), 2.52 (q, J=7.3 Hz, 2H), 4.10 (s br, 1H), 7.25 (s, 2H).

c) The title compound is then prepared from the above 4-amino-3-ethyl-5-methyl-benzonitrile in analogy to 3-chloro-N-hydroxy-4-methanesulfonylamino-5-methyl-benzamidine; LC-MS**: t_R=0.26 min, [M+1]⁺=272.32.

3-Chloro-4-ethanesulfonylamino N-hydroxy-5-methyl-benzamidine

The title compound is prepared in analogy to 3-chloro-N-hydroxy-4-methanesulfonylamino-5-methyl-benzamidine using ethanesulfonylchloride; LC-MS**: t_R=0.27 min, [M+1]⁺=292.13; ¹H NMR (D₆-DMSO): δ 1.36 (t, J=7.5 Hz, 3H), 2.40 (s, 3H), 3.22 (q, J=7.5 Hz), 5.88 (s, 2H), 7.57 (d, J=1.5 Hz, 1H), 7.63 (d, J=1.5 Hz, 1H), 9.18 (s, 1H), 9.78 (s, 1H).

4-Benzyloxy-3-ethyl-5-methyl-benzoic acid

a) To a solution of 3-ethyl-4-hydroxy-5-methyl-benzaldehyde (34.9 g, 0.213 mol, prepared from 2-ethyl-6-methyl-phenol according to the literature cited for 3-ethyl-4,N-dihydroxy-5-methyl-benzamidine) in MeCN (350 mL), K₂CO₃ (58.7 g, 0.425 mol) and benzylbromide (36.4 g, 0.213 mol) are added. The mixture is stirred at 60° C. for 2 h before it is cooled to rt, diluted with water and extracted twice with EA. The org. extracts are washed with water and concentrated to give crude 4-benzyloxy-3-ethyl-5-methyl-benzaldehyde (45 g) as an orange oil. ¹H NMR (CDCl₃): δ1.29 (t, J=7.5 Hz, 3H), 2.40 (s, 3H), 2.77 (q, J=7.8 Hz, 2H), 4.90 (s, 2H), 7.31-7.52 (m, 5H), 7.62 (d, J=1.5 Hz, 1H), 7.66 (d, J=1.8 Hz, 1H), 9.94 (s, 1H).
b) To a mixture of 4-benzyloxy-3-ethyl-5-methyl-benzaldehyde (132 g, 0.519 mol) and 2-methyl-2-butene (364 g, 5.19 mol) in tert.-butanol (1500 mL), a solution of NaH₂PO₄ dihydrate (249 g, 2.08 mol) in water (1500 mL) is added. To this mixture, NaClO₂ (187.8 g, 2.08 mol) is added in portions. The temperature of the reaction mixture is kept below 30° C., and evolution of gas is observed. Upon completion of the addition, the orange bi-phasic mixture is stirred well for 3 h before it is diluted with TBME (1500 mL). The org. layer is separated and washed with 20% aq. NaHS solution (1500 mL) and water (500 mL). The org. phase is then extracted three times with 0.5 N aq. NaOH (1000 mL), the aq. phase is acidified with 25% aq. HCl (500 mL) and extracted twice with TBME (1000 mL). These org. extracts are combined and evaporated to dryness to give the title compound; ¹H NMR (D₆-DMSO): δ 1.17 (t, J=7.5 Hz, 3H), 2.31 (s, 3H), 2.67 (q, J=7.5 Hz, 2H), 4.86 (s, 2H), 7.34-7.53 (m, 5H), 7.68 (s, 2H), 12.70 (s, 1H).

Example 1 (S)-3-(2-Ethyl-4-{5-[2-(1-ethyl-propyl)-6-methoxy-pyridin-4-yl]-[1,2,4]oxadiazol-3-yl}-6-methyl-phenoxy)-propane-1,2-diol

a) To a solution of 2-(1-ethyl-propyl)-6-methoxy-isonicotinic acid (190 mg, 732 μmol) in THF (10 mL) and DMF (2 mL), DIPEA (190 mg, 1.46 mmol) followed by TBTU (235 mg, 732 μmol) is added. The mixture is stirred at rt for 10 min before (R)-4-(2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-3-ethyl-N-hydroxy-5-methyl-benzamidine 226 mg, 732 μmol) is added. The mixture is stirred at rt for 1 h before it is diluted with EA and washed with water. The org. phase is separated and concentrated. The remaining residue is dissolved in dioxane (10 mL) and heated to 105° C. for 18 h. The mixture is cooled to rt, concentrated and the crude product is purified on prep. TLC plates using DCM containing 10% of methanol to give 4-{3-[4-((R)-2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-3-ethyl-5-methyl-phenyl]-[1,2,4]oxadiazol-5-yl}-2-(1-ethyl-propyl)-6-methoxy-pyridine (256 mg) as a yellow oil; LC-MS: t_R=1.28 min, [M+H]⁺=496.23.

b) A solution of 4-{3-[4-((R)-2,2-dimethyl-[1,3]dioxolan-4-ylmethoxy)-3-ethyl-5-methyl-phenyl]-[1,2,4]oxadiazol-5-yl}-2-(1-ethyl-propyl)-6-methoxy-pyridine (250 mg, 504 μmol) in 4 M HCl in dioxane (10 mL) is stirred at rt for 90 min before it is concentrated. The crude product is purified on prep. TLC plates using DCM containing 10% of methanol to give the title compound (76 mg) as a pale brownish solid; LC-MS: t_R=1.12 min, [M+H]⁺=456.12; ¹H NMR (CDCl₃): δ0.85 (t, J=7.0 Hz, 6H), 1.33 (t, J=7.0 Hz, 3H), 1.70-1.89 (m, 4H), 2.42 (s, 3H), 2.61-2.71 (m, 1H), 2.78 (q, J=7.3 Hz, 2H), 3.82-4.00 (m, 4H), 4.04 (s, 3H), 4.14-4.21 (m, 1H), 7.34 (s, 1H), 7.46 (s, 1H), 7.86-7.91 (m, 2H).

Example 2 (S)-3-{4-[5-(2-Cyclopentyl-6-methoxy-pyridin-4-yl)-[1,2,4]oxadiazol-3-yl]-2-ethyl-6-methyl-phenoxy}-propane-1,2-diol

The title compound is prepared in analogy to Example 1 starting from 2-cyclopentyl-6-methoxy-isonicotinic acid; LC-MS: t_R=1.14 min, [M+H]⁺=454.16; ¹H NMR (CDCl₃): δ1.33 (t, J=7.5 Hz, 3H), 1.72-1.78 (m, 2H), 1.85-1.94 (m, 4H), 2.03-2.15 (m, 2H), 2.41 (s, 3H), 2.72 (d, J=5.3 Hz, 1H), 2.77 (q, J=7.5 Hz, 2H), 3.19-3.28 (m, 1H), 3.81-3.94 (m, 2 H), 3.95-3.98 (m, 2H), 4.02 (s, 3H), 4.14-4.21 (m, 1H), 7.31 (d, J=1.3 Hz, 1H), 7.51 (d, J=1.0 Hz, 1H), 7.88 (d, J=1.8 Hz), 7.89 (d, J=2.0 Hz, 1H).

PAPER

A practical synthesis of S1P receptor 1 agonist ACT-334441 (1) through late-stage convergent coupling of two key intermediates is described. The first intermediate is 2-cyclopentyl-6-methoxyisonicotinic acid whose skeleton was built from 1-cyclopentylethanone, ethyl oxalate, and cyanoacetate in a Guareschi–Thorpe reaction in 42% yield over five steps. The second, chiral intermediate, is a phenol ether derived from enantiomerically pure (R)-isopropylidene glycerol ((R)-solketal) and 3-ethyl-4-hydroxy-5-methylbenzonitrile in 71% yield in a one-pot reaction. The overall sequence entails 18 chemical steps with 10 isolated intermediates. All raw materials are cheap and readily available in bulk quantities, the reaction conditions match with standard pilot plant equipment, and the route reproducibly afforded 3–20 kg of 1 in excellent purity and yield for clinical studies.

Practical Synthesis of a S1P Receptor 1 Agonist via a Guareschi–Thorpe Reaction

RPL-554

• Molecular FormulaC₂₆H₃₁N₅O₄
• Average mass477.555

CFTR stimulator; PDE 3 inhibitor; PDE 4 inhibitor

RPL-554 is a mixed phosphodiesterase (PDE) III/IV inhibitor in phase II clinical development at Verona Pharma for the treatment of asthma, allergic rhinitis, chronic obstructive pulmonary disease (COPD) and inflammation.

RPL-554 is expected to have long duration of action and will be administered nasally thereby preventing gastrointestinal problems often resulting from orally administered PDE4 antiinflammatory drugs.

The company is now seeking licensing agreements or partnerships for the further development and commercialization of the drug.

RPL-554 (LS-193,855) is a drug candidate for respiratory diseases. It is an analog of trequinsin, and like trequinsin, is a dual inhibitor of the phosphodiesterase enzymes PDE-3 and PDE-4.^[1] As of October 2015, inhaled RPL-554 delivered via a nebulizer was in development for COPD and had been studied in asthma.^[2]

PDE3 inhibitors act as bronchodilators, while PDE4 inhibitors have an anti-inflammatory effect.^[1][3]

RPL554 was part of a family of compounds invented by Sir David Jack, former head of R&D for GlaxoSmithKline, and Alexander Oxford, a medicinal chemist; the patents on their work were assigned to Vernalis plc.^[4][5]:19-20

In 2005, Rhinopharma Ltd, acquired the rights to the intellectual property from Vernalis.^[5]:19-20 Rhinopharma was a startup founded in Vancouver, Canada in 2004 by Michael Walker, Clive Page, and David Saint, to discover and develop drugs for chronic respiratory diseases,^[5]:16 and intended to develop RPL-554, delivered with an inhaler, first for allergic rhinitis, then asthma, then forCOPD.^[5]:16-17 RPL554 was synthesized at Tocris, a contract research organization, under the supervision of Oxford, and was studied in collaboration with Page’s lab at King’s College, London.^[1] In 2006 Rhinopharma recapitalized and was renamed Verona Pharma plc.^[5]

This was first seen in April 2015 when it was published as a France national. Verona Pharma (formerly Rhinopharma), under license from Kings College via Vernalis, is developing the long-acting bronchodilator, RPL-554 the lead in a series dual inhibitor of multidrug resistant protein-4 and PDE 3 and 4 inhibiting trequinsin analogs which included RPL-565, for treating inflammatory respiratory diseases, such as allergic rhinitis, asthma, and COPD.

RPL554

Verona Pharma’s lead drug, RPL554, is a “first-in-class” inhaled drug under development for chronic obstructive pulmonary disease (COPD), asthma and cystic fibrosis. The drug is an inhibitor of the phosphodiesterase 3 (PDE3) and phosphodiesterase 4 (PDE4) enzymes, two enzymes known to be of importance in the development and progression of immunological respiratory diseases. The drug has the potential to act as both a bronchodilator and an anti-inflammatory which would significantly differentiate it from existing drugs.

RPL554 was selected from a class of compounds co-invented by Sir David Jack, the former Director of Research at Glaxo who led the team that discovered many of the commercially successful drugs in the respiratory market.

Verona Pharma has successfully completed two double-blind placebo controlled randomised Phase 2b studies of RPL554: one in mild to moderate asthma and another in mild to moderate COPD. The drug was found to be well tolerated, free from drug-related adverse effects (especially cardiovascular and gastro-intestinal effects) and generated significant bronchodilation.  Additionally, double-blind placebo controlled exploratory studies in healthy volunteers challenged with an inhaled irritant also generated consistent, clinically meaningful anti-inflammatory effects.

Verona Pharma is also carrying out exploratory studies to investigate the potential of RPL554 as a novel treatement for cystic fibrosis. In November 2014, the Company received a Venture and Innovation Award from the UK Cystic Fibrosis Trust to further such studies.

For further information on the potential of RPL554 for the treatment of respiratory diseases, refer to the peer-reviewed paper available on-line in the highly-respected medication journal, The Lancet Respiratory Medicine, entitled “Efficacy and safety of RPL554, a dual PDE3 and PDE4 inhibitor, in healthy volunteers and in patients with asthma or chronic obstructive pulmonary disease: findings from four clinical trials”.

The competitive advantages of RPL554 include the following:

• combining bronchodilator (PDE 3) and anti-inflammatory actions (PDE 4) in a single drug, something that is currently only achieved with a combination LABA and glucocorticosteroid inhaler,
• unique in not using steroids or beta agonists, which have known side effects,
• planned to be administered by nasal inhalation, thereby reducing the unwanted gastrointestinal side effects of many orally administered drugs.

History of Clinical Trials

• Following completion in May 2008 of toxicological studies of RPL554, the Company commenced in February 2009 a Phase I/IIa clinical trial of the drug at the Centre for Human Drug Research (CHDR) at Leiden in the Netherlands. In September 2009, the Company announced that it had successfully completed the trial, demonstrating that RPL554 has a good safety profile and has beneficial effects in terms of bronchodilation and bronchoprotection in asthmatics and a reduction in the numbers of inflammatory cells in the nasal passages of allergic rhinitis patients.
• In November 2010, the Company successfully completed a further trial that examined the safety and bronchodilator effectiveness of the drug administered at higher doses.
• In August 2011, the Company demonstrated that bronchodilation is maintained over a period of 6 days with daily dosing of RPL554 in asthmatics.
• In November 2011, the Company successfully demonstrated safety and bronchodilation of RPL554 in patients with mild to moderate forms of COPD.
• In March 2013, the Company demonstrated positive airway anti-inflammatory activity with respect to COPD at a clinical trial carried out at the Medicines Evaluation Unit (MEU) in Manchester, UK.

Synthesis

WO 2000058308

Cyclization of 1-(3,4-dimethoxyphenethyl)barbituric acid  in refluxing POCl3 produces the pyrimidoisoquinolinone , which is further condensed with 2,4,6-trimethylaniline  in boiling isopropanol to afford the trimethylphenylimino derivative . Subsequent alkylation of with N-(2-bromoethyl)phthalimide in the presence of K2CO3 and KI, followed by hydrazinolysis of the resulting phthalimidoethyl compound  yields the primary amine . This is finally converted into the title urea RPL 554 by reaction with sodium cyanate in aqueous HCl.

Example 1 : 9 Λ 0-Dimethoxy-2-(2.4-6-trimethy-phen yliminoY-3-(N-carbamoyl-2- aminoethylV3.4.6.7-tetrahydro-2H-pyrimido[6.1-a]isoquinolin-4-one

Sodium cyanate (6.0g, 0.092 mol) in water (100 ml) was added dropwise to a stirred solution of 9,10-Dimethoxy-2-(2,4,6-trimethylphenylimino)-3-(2-aminoethyl)-3,4,6,7- tetrahydro-2H-pyrimido[6,l-a]isoquinolin-4-one, prepared according to Preparation 4 above (20.0g, 0.046 mol) in water (600 ml) and IN ΗC1 (92 ml) at 80°C. After stirring for 2h at 80°C the mixture was cooled in an ice-bath and basified with 2N NaOH. The mixture was extracted with dichloromethane (3 x 200 ml) and the combined extract was dried (MgSO- ) and evaporated in vacuo. The resulting yellow foam was purified by column chromatography on silica gel eluting with CH2CI2 / MeOH (97:3) and triturated with ether to obtain the title compound as a yellow solid, 11.9g, 54%.

M.p.: 234-236°C m/z: C26H31N5O4 requires M=477 found (M+l) = 478

HPLC: Area (%) 99.50 Column ODS (150 x 4.6 mm)

MP pH3 KH₂PO₄ / CH3CN (60/40)

FR (ml/min) 1.0 RT (min) 9.25 Detection 250 nm

^lK NMR (300 MHz, CDCI3): δ 1.92 (1H, br s, NH), 2.06 (6H, s, 2xCH₃), 2.29 (3H, s, CH₃), 2.92 (2H, t, CH₂), 3.53 (2H, m, CH₂), 3.77 (3H, s, OCH3), 3.91 (3H, s, OCH3), 4.05 (2H, t, CH₂), 4.40 (2H, t, CH₂), 5.35 (2H, br s, NH₂), 5.45 (1H, s, C=CH), 6.68 (1H, s, ArH), 6.70 (1H, s, ArH), 6.89 (2H, s, 2xArH).

Preparation 1 : Synthesis of 2-Chloro-6.7-d-hydro-9.10-Dimethoxy-4H-pyrimido- [6,l-a]isoquinoHn-4-one (shown as (1) in Figure 1

A mixture of l-(3,4-dimethoxyphenyl) barbituric acid (70g, 0.24mol), prepared according to the method described in B. Lai et al. J.Med.Chem. 27 1470-1480 (1984), and phosphorus oxychloride (300ml, 3.22mol) was refluxed for 2.5h. The excess phosphorous oxychloride was removed by distillation (20mmHg) on wa ming. After cooling the residue was slurried in dioxan (100ml) and cautiously added to a vigorously stirred ice/water solution (11). Chloroform (11) was added and the resulting mixture was basified with 30% sodium hydroxide solution. The organic layer was separated and the aqueous phase further extracted with chloroform (2x750ml). The combined organic extracts were washed with water (1.51), dried over magnesium sulphate and concentrated in vacuo to leave a gummy material (90g). This was stirred in methanol for a few minutes, filtered and washed with methanol (200ml), diethyl ether (2x200ml) and dried in vacuo at 40°C to yield the title compound as a yellow/orange solid. 47g, 62%

(300MHz, CDCI3) 2.96(2H, t, C(₇) H₂); 3.96(6H, s, 2xOCH₃; 4.20(2H, t, C(₆₎ H₂); 6.61(1H, s, C₍₁₎ H); 6.76(1H, s, Ar-H); 7.10(1H, s, Ar-H). Preparation 2: 9.10-Dimethoxy-2-(2.4.6-trimethylphenyliminoV3.4.6.7- tetrahydro-2H-pyrimido[6.1-a]isoquinolin-4-one (shown as (2) in Figure 1

2-Chloro-9,10-dimethoxy-6,7-dihydro-4H-pyrimido[6,l-a]isoquinolin-4-one, prepared according to Preparation 1, (38.5g, 0.13 mol) and 2,4,6-trimethylaniline (52.7g, 0.39 mol) in propan-2-ol (3 1) was stirred and heated at reflux, under nitrogen, for 24h. After cooling to room temperature, the solution was evaporated in vacuo and the residue was purified by column chromatography on silica gel, eluting with CΗ2CI2 /

MeOH, initially 98:2, changing to 96:4 once the product began to elute from the column. The title compound was obtained with a slight impurity, (just above the product on tic). Yield 34.6g, 67%.

Preparation 3: 9.10-Dimethoxy-2-(2.4.6-trimethylphenyliminoV3-(2-N- phthalimidoethyπ-3.4.6.7-tetrahydro-2H-pyrimido[6.1-a]isoquinolin-4-one

(shown as (3 in Figure 1)

A mixture of 9,10-Dimethoxy-2-(2,4,6-trimethylphenylimino)-3,4,6,7-tetrahydro-2H- pyrimido[6,l-a]isoquinolin-4-one (which was prepared according to Preparation 2) (60.0g, 0.153 mol), potassium carbonate (191g, 1.38 mol), sodium iodide (137g, 0.92 mol) and N-(2-bromoethyl)phthalimide (234g, 0.92 mol) in 2-butanone (1500 ml) was stirred and heated at reflux, under nitrogen, for 4 days. After cooling to room temperature the mixture was filtered and the filtrate was evaporated in vacuo. The residue was treated with methanol (1000 ml) and the solid filtered off, washed with methanol and recrystallised from ethyl acetate to obtain the title compound as a pale yellow solid in yield 40. Og, 46%. Evaporation of the mother liquor and column chromatography of the residue on silica gel (CΗ2C-2 / MeOH 95:5) provided further product 11.7g, 13.5%. Preparation 4: 9.10-Dimethoxy-2-(2A6-trimethylphenylimino)-3-(2-arninoethyO- 3.4.6.7-tetrahydro-2H-pyrimido[6.1-a]isoquino-in-4-one (shown as (4) in Figure 1)

A mixture of 9,10-Dimethoxy-2-(2,4,6-trimethylphenylimino)-3-(2-N- phthalimidoethyl)-3,4,6,7-tetrahydro-2H-pyrimido[6,l-a]isoquinolin-4-one (22. Og, 0.039 mol), prepared according to Preparation 3, and hydrazine hydrate (11.3g, 0.195 mol) in chloroform (300 ml) and ethanol (460 ml) was stined at room temperature, under nitrogen, for 18h. Further hydrazine hydrate (2.9g, 0.05 mol) was added and the mixture was stirred a further 4h. After cooling in ice / water, the solid was removed by filtration and the filtrate evaporated in vacuo. The residue was dissolved in dichloromethane and the insoluble material was removed by filtration. The fitrate was dried (MgSO-i) and evaporated in vacuo to afford the title compound as a yellow foam in yield 16.2g, 96%.

PATENT

WO-2016128742

Novel crystalline acid addition salts forms of RPL-554 are claimed, wherein the salts, such as ethane- 1,2-disulfonic acid, ethanesulfonic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, hydrochloric acid, hydrobromic acid, phosphoric acid or sulfuric acid. .

RPL554 (9, 10-dimethoxy-2-(2,4,6-trimethylphenylimino)-3-(/V-carbamoyl-2-aminoethyl)-3,4,6,7-tetrahydro-2H-pyrimido[6, l-a]isoquinolin-4-one) is a dual PDE3/PDE4 inhibitor and is described in WO 00/58308. As a combined PDE3/PDE4 inhibitor, RPL554 has both antiinflammatory and bronchodilatory activity and is useful in the treatment of respiratory disorders such as asthma and chronic obstructive pulmonary disease (COPD). The structure of RPL554 is shown below.

Owing to its applicability in the treatment of respiratory disorders, it is often preferable to administer RPL554 by inhalation. Franciosi et al. disclose a solution of RPL554 in a citrate-phosphate buffer at pH 3.2 (The Lancet: Respiratory Medicine 11/2013; l(9):714-27. DOI: 10.1016/S2213-2600(13)70187-5). The preparation of salts of RPL554 has not been described.

PATENT

http://www.google.ch/patents/WO2000058308A1?cl=en&hl=de

PATENT

http://www.google.ch/patents/WO2012020016A1?cl=en

U.S. Pat. No. 6,794,391, 7,378,424, and 7,105,663, which are each incorporated herein by reference, discloses compound RPL-554 (N-{2-[(2iT)-2-(mesityiimino)-9,10- dimethoxy-4-oxo-6,7-dihydro-2H-pyrimido[6,l-a]-isoquinolin-3 4H)-yl]ethyl}urea).

It would be beneficial to provide a composition of a stable polymorph of RPL-554, that has advanrtages over less stable polymorphs or amorphous forms, including

stability, compressibility, density, dissolution rates, increased potency or. lack toxicity.

References

1. Boswell-Smith V et al. The pharmacology of two novel long-acting phosphodiesterase 3/4 inhibitors, RPL554 [9,10-dimethoxy-2(2,4,6-trimethylphenylimino)-3-(n-carbamoyl-2-aminoethyl)-3,4,6,7-tetrahydro-2H-pyrimido[6,1-a]isoquinolin-4-one] and RPL565 [6,7-dihydro-2-(2,6-diisopropylphenoxy)-9,10-dimethoxy-4H-pyrimido[6,1-a]isoquinolin-4-one]. J Pharmacol Exp Ther. 2006 Aug;318(2):840-8. PMID 16682455
2.  Nick Paul Taylor for FierceBiotech. October 1, 2015 Verona sets sights on PhIIb after COPD drug comes through early trial
3.  Turner MJ et al. The dual phosphodiesterase 3 and 4 inhibitor RPL554 stimulates CFTR and ciliary beating in primary cultures of bronchial epithelia. Am J Physiol Lung Cell Mol Physiol. 2016 Jan 1;310(1):L59-70. PMID 26545902
4. Jump up^ see US20040171828, identified in the citations of PMID 16682455
5. ISIS Resources, PLC. August 23, 2006 Proposed Acquisition of Rhinopharma

REFERENCES

1: Calzetta L, Cazzola M, Page CP, Rogliani P, Facciolo F, Matera MG. Pharmacological characterization of the interaction between the dual phosphodiesterase (PDE) 3/4 inhibitor RPL554 and glycopyrronium on human isolated bronchi and small airways. Pulm Pharmacol Ther. 2015 Jun;32:15-23. doi: 10.1016/j.pupt.2015.03.007. Epub 2015 Apr 18. PubMed PMID: 25899618.

2: Franciosi LG, Diamant Z, Banner KH, Zuiker R, Morelli N, Kamerling IM, de Kam ML, Burggraaf J, Cohen AF, Cazzola M, Calzetta L, Singh D, Spina D, Walker MJ, Page CP. Efficacy and safety of RPL554, a dual PDE3 and PDE4 inhibitor, in healthy volunteers and in patients with asthma or chronic obstructive pulmonary disease: findings from four clinical trials. Lancet Respir Med. 2013 Nov;1(9):714-27. doi: 10.1016/S2213-2600(13)70187-5. Epub 2013 Oct 25. PubMed PMID: 24429275.

3: Wedzicha JA. Dual PDE 3/4 inhibition: a novel approach to airway disease? Lancet Respir Med. 2013 Nov;1(9):669-70. doi: 10.1016/S2213-2600(13)70211-X. Epub 2013 Oct 25. PubMed PMID: 24429260.

4: Calzetta L, Page CP, Spina D, Cazzola M, Rogliani P, Facciolo F, Matera MG. Effect of the mixed phosphodiesterase 3/4 inhibitor RPL554 on human isolated bronchial smooth muscle tone. J Pharmacol Exp Ther. 2013 Sep;346(3):414-23. doi: 10.1124/jpet.113.204644. Epub 2013 Jun 13. PubMed PMID: 23766543.

5: Gross N. The COPD pipeline XX. COPD. 2013 Feb;10(1):104-6. doi: 10.3109/15412555.2013.766103. PubMed PMID: 23413896.

6: Gross NJ. The COPD Pipeline XIV. COPD. 2012 Feb;9(1):81-3. doi: 10.3109/15412555.2012.646587. PubMed PMID: 22292600.

7: Boswell-Smith V, Spina D, Oxford AW, Comer MB, Seeds EA, Page CP. The pharmacology of two novel long-acting phosphodiesterase 3/4 inhibitors, RPL554 [9,10-dimethoxy-2(2,4,6-trimethylphenylimino)-3-(n-carbamoyl-2-aminoethyl)-3,4,6, 7-tetrahydro-2H-pyrimido[6,1-a]isoquinolin-4-one] and RPL565 [6,7-dihydro-2-(2,6-diisopropylphenoxy)-9,10-dimethoxy-4H-pyrimido[6,1-a]isoquino lin-4-one]. J Pharmacol Exp Ther. 2006 Aug;318(2):840-8. Epub 2006 May 8. PubMed PMID: 16682455.

RPL-554

Systematic (IUPAC) name
N-{2-[(2E)-2-(mesitylimino)-9,10-dimethoxy-4-oxo-6,7-dihydro-2H-pyrimido[6,1-a]-isoquinolin-3(4H)-yl]ethyl}urea
Identifiers
PubChem	CID 9934746
ChemSpider	8110374
Synonyms	9,10-Dimethoxy-2-(2,4,6-trimethylphenylimino)-3-(N-carbamoyl-2-aminoethyl)-3,4,6,7-tetrahydro-2H-pyrimido[6,1-a]isoquinolin-4-one
Chemical data
Formula	C26H31N5O4
Molar mass	477.554 g/mol

///////////RPL-554, LS-193,855, 298680-25-8, UNII:3E3D8T1GIX, RPL554, RPL 554, phase 2, Chronic Obstructive Pulmonary Diseases , COPD, Allergic Rhinitis, Asthma Therapy, Cystic Fibrosis, Inflammation, Bronchodilators

Cc3cc(C)cc(C)c3N=c2cc1-c(cc4OC)c(cc4OC)CCn1c(=O)n2CCNC(N)=O