New Drug Approvals

Home » Uncategorized (Page 94)

Category Archives: Uncategorized

DRUG APPROVALS BY DR ANTHONY MELVIN CRASTO .....FOR BLOG HOME CLICK HERE

Blog Stats

  • 4,896,904 hits

Flag and hits

Flag Counter

Enter your email address to follow this blog and receive notifications of new posts by email.

Join 37.8K other subscribers
Follow New Drug Approvals on WordPress.com

Archives

Categories

Recent Posts

Flag Counter

ORGANIC SPECTROSCOPY

Read all about Organic Spectroscopy on ORGANIC SPECTROSCOPY INTERNATIONAL 

Enter your email address to follow this blog and receive notifications of new posts by email.

Join 37.8K other subscribers
DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO, Born in Mumbai in 1964 and graduated from Mumbai University, Completed his Ph.D from ICT, 1991,Matunga, Mumbai, India, in Organic Chemistry, The thesis topic was Synthesis of Novel Pyrethroid Analogues, Currently he is working with AFRICURE PHARMA, ROW2TECH, NIPER-G, Department of Pharmaceuticals, Ministry of Chemicals and Fertilizers, Govt. of India as ADVISOR, earlier assignment was with GLENMARK LIFE SCIENCES LTD, as CONSUlTANT, Retired from GLENMARK in Jan2022 Research Centre as Principal Scientist, Process Research (bulk actives) at Mahape, Navi Mumbai, India. Total Industry exp 32 plus yrs, Prior to joining Glenmark, he has worked with major multinationals like Hoechst Marion Roussel, now Sanofi, Searle India Ltd, now RPG lifesciences, etc. He has worked with notable scientists like Dr K Nagarajan, Dr Ralph Stapel, Prof S Seshadri, etc, He did custom synthesis for major multinationals in his career like BASF, Novartis, Sanofi, etc., He has worked in Discovery, Natural products, Bulk drugs, Generics, Intermediates, Fine chemicals, Neutraceuticals, GMP, Scaleups, etc, he is now helping millions, has 9 million plus hits on Google on all Organic chemistry websites. His friends call him Open superstar worlddrugtracker. His New Drug Approvals, Green Chemistry International, All about drugs, Eurekamoments, Organic spectroscopy international, etc in organic chemistry are some most read blogs He has hands on experience in initiation and developing novel routes for drug molecules and implementation them on commercial scale over a 32 PLUS year tenure till date Feb 2023, Around 35 plus products in his career. He has good knowledge of IPM, GMP, Regulatory aspects, he has several International patents published worldwide . He has good proficiency in Technology transfer, Spectroscopy, Stereochemistry, Synthesis, Polymorphism etc., He suffered a paralytic stroke/ Acute Transverse mylitis in Dec 2007 and is 90 %Paralysed, He is bound to a wheelchair, this seems to have injected feul in him to help chemists all around the world, he is more active than before and is pushing boundaries, He has 100 million plus hits on Google, 2.5 lakh plus connections on all networking sites, 100 Lakh plus views on dozen plus blogs, 227 countries, 7 continents, He makes himself available to all, contact him on +91 9323115463, email amcrasto@gmail.com, Twitter, @amcrasto , He lives and will die for his family, 90% paralysis cannot kill his soul., Notably he has 38 lakh plus views on New Drug Approvals Blog in 227 countries......https://newdrugapprovals.wordpress.com/ , He appreciates the help he gets from one and all, Friends, Family, Glenmark, Readers, Wellwishers, Doctors, Drug authorities, His Contacts, Physiotherapist, etc He has total of 32 International and Indian awards

Verified Services

View Full Profile →

Archives

Categories

Flag Counter

Continuous Manufacturing of Solid Oral Drug Products: It’s Time for Change


CS 3150, angiotensin II receptor antagonist, for the treatment or prevention of such hypertension and heart disease


 

CS-3150,  (XL550)

CS 3150, angiotensin II receptor antagonist,  for the treatment or prevention of such hypertension and heart disease similar to olmesartan , losartan, candesartan , valsartan,  irbesartan,  telmisartan, eprosartan,

 Cas name 1H-​Pyrrole-​3-​carboxamide, 1-​(2-​hydroxyethyl)​-​4-​methyl-​N-​[4-​(methylsulfonyl)​phenyl]​-​5-​[2-​(trifluoromethyl)​phenyl]​-​, (5S)​-

CAS 1632006-28-0 for S conf

MF C22 H21 F3 N2 O4 S

MW 466.47

(S)-1-(2-hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide

CAS 1632006-28-0 for S configuration

1- (2-hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxamide

(S) -1- (2- hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxamide

(+/-)-1-(2-hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide, CAS 880780-76-7

(+)-1-(2-hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide..1072195-82-4

(-)-1-(2-hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide..1072195-83-5

WO 2014168103

WO 2008126831

WO2008 / 126831 (US Publication US2010-0093826)http://www.google.co.in/patents/EP2133330A1?cl=en

WO 2015012205

WO 2006012642..compound A;..http://www.google.com/patents/WO2006012642A2?cl=en

WO2006 / 012642 (US Publication US2008-0234270)

WO 2015030010…http://www.google.com/patents/WO2015030010A1?cl=en

 

 

JAPAN PHASE 2……….Phase 2 Study to Evaluate Efficacy and Safety of CS-3150 in Patients with Essential Hypertension

http://www.clinicaltrials.jp/user/showCteDetailE.jsp?japicId=JapicCTI-121921

Phase II Diabetic nephropathies; Hypertension

  • 01 Jan 2015 Daiichi Sankyo initiates a phase IIb trial for Diabetic nephropathies in Japan (NCT02345057)
  • 01 Jan 2015 Daiichi Sankyo initiates a phase IIb trial for Hypertension in Japan (NCT02345044)
  • 01 May 2013 Phase-II clinical trials in Diabetic nephropathies in Japan (PO)
  •  Currently, angiotensin II receptor antagonists and calcium antagonists are widely used as a medicament for the treatment or prevention of such hypertension or heart disease.
     Mineralocorticoid receptor (MR) (aldosterone receptor) has been known to play an important role in the control of body electrolyte balance and blood pressure, spironolactone having a steroid structure, MR antagonists such as eplerenone, are known to be useful in the treatment of hypertension-heart failure.
     Renin – angiotensin II receptor antagonists are inhibitors of angiotensin system is particularly effective in renin-dependent hypertension, and show a protective effect against cardiovascular and renal failure. Also, the calcium antagonists, and by the function of the calcium channel antagonizes (inhibits), since it has a natriuretic action in addition to the vasodilating action, is effective for hypertension fluid retention properties (renin-independent) .
     Therefore, the MR antagonist, when combined angiotensin II receptor antagonists or calcium antagonists, it is possible to suppress the genesis of multiple hypertension simultaneously, therapeutic or prophylactic effect of the stable and sufficient hypertension irrespective of the etiology is expected to exhibit.
     Also, diuretics are widely used as a medicament for the treatment or prevention of such hypertension or heart disease. Diuretic agent is effective in the treatment of hypertension from its diuretic effect. Therefore, if used in combination MR antagonists and diuretics, the diuretic effect of diuretics, it is possible to suppress the genesis of multiple blood pressure at the same time, shows a therapeutic or prophylactic effect of the stable and sufficient hypertension irrespective of the etiology it is expected.
     1- (2-hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxamide (hereinafter, compound ( I)) is, it is disclosed in Patent Documents 1 and 2, hypertension, for the treatment of such diabetic nephropathy are known to be useful.

CS-3150 (XL550) is a small-molecule antagonist of the mineralocorticoid receptor (MR), a nuclear hormone receptor implicated in a variety of cardiovascular and metabolic diseases. MR antagonists can be used to treat hypertension and congestive heart failure due to their vascular protective effects. Recent studies have also shown beneficial effects of adding MR antagonists to the treatment regimen for Type II diabetic patients with nephropathy. CS-3150 is a non-steroidal, selective MR antagonist that has the potential for the treatment of hypertension, congestive heart failure, or end organ protection due to vascular damage.

Useful as a mineralocorticoid receptor (MR) antagonist, for treating hypertension, cardiac failure and diabetic nephropathy. It is likely to be CS-3150, a non-steroidal MR antagonist, being developed by Daiichi Sankyo (formerly Sankyo), under license from Exelixis, for treating hypertension and diabetic nephropathy (phase 2 clinical, as of March 2015). In January 2015, a phase II trial for type 2 diabetes mellitus and microalbuminuria was planned to be initiated later that month (NCT02345057).

Exelixis discovered CS-3150 and out-licensed the compound to Daiichi-Sankyo. Two phase 2a clinical trials, one in hypertensive patients and the other in type 2 diabetes with albuminuria, are currently being conducted in Japan by Daiichi-Sankyo.

 

Mineralocorticoid receptor (MR) (aldosterone receptor) has been known to play an important role in the control of body electrolyte balance and blood pressure, spironolactone having a steroid structure, MR antagonists such as eplerenone, are known to be useful in the treatment of hypertension-heart failure.

CS-3150 (XL550) is a small-molecule antagonist of the mineralocorticoid receptor (MR), a nuclear hormone receptor implicated in a variety of cardiovascular and metabolic diseases. MR antagonists can be used to treat hypertension and congestive heart failure due to their vascular protective effects. Recent studies have also shown beneficial effects of adding MR antagonists to the treatment regimen for Type II diabetic patients with nephropathy. CS-3150 is a non-steroidal, selective MR antagonist that has the potential for the treatment of hypertension, congestive heart failure, or end organ protection due to vascular damage.

Exelixis discovered CS-3150 and out-licensed the compound to Daiichi-Sankyo. Two phase 2a clinical trials, one in hypertensive patients and the other in type 2 diabetes with albuminuria, are currently being conducted in Japan by Daiichi-Sankyo.

Daiichi Sankyo (formerly Sankyo), under license from Exelixis, is developing CS-3150 (XL-550), a non-steroidal mineralocorticoid receptor (MR) antagonist, for the potential oral treatment of hypertension and diabetic nephropathy, microalbuminuria ,  By October 2012, phase II development had begun ; in May 2014, the drug was listed as being in phase IIb development . In January 2015, a phase II trial for type 2 diabetes mellitus and microalbuminuria was planned to be initiated later that month. At that time, the trial was expected to complete in March 2017 .

Exelixis, following its acquisition of X-Ceptor Therapeutics in October 2004 , was investigating the agent for the potential treatment of metabolic disorders and cardiovascular diseases, such as hypertension and congestive heart failure . In September 2004, Exelixis expected to file an IND in 2006. However, it appears that the company had fully outlicensed the agent to Sankyo since March 2006 .

Description Small molecule antagonist of the mineralocorticoid receptor (MR)
Molecular Target Mineralocorticoid receptor
Mechanism of Action Mineralocorticoid receptor antagonist
Therapeutic Modality Small molecule

In January 2015, a multi-center, placebo-controlled, randomized, 5-parallel group, double-blind, phase II trial (JapicCTI-152774;  NCT02345057; CS3150-B-J204) was planned to be initiated later that month in Japan, in patients with type 2 diabetes mellitus and microalbuminuria, to assess the efficacy and safety of different doses of CS-3150 compared to placebo. At that time, the trial was expected to complete in March 2017; later that month, the trial was initiated in the Japan

By October 2012, phase II development had begun in patients with essential hypertension

By January 2011, phase I trials had commenced in Japan

Several patents WO-2014168103,

WO-2015012205 and WO-2015030010

XL-550, claimed in WO-2006012642,

………………………………………………………………….

http://www.google.co.in/patents/EP2133330A1?cl=en

(Example 3)(+/-)-1-(2-hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide

  • After methyl 4-methyl-5-[2-(trifluoromethyl) phenyl]-1H-pyrrole-3-carboxylate was obtained by the method described in Example 16 of WO 2006/012642 , the following reaction was performed using this compound as a raw material.
  • Methyl 4-methyl-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxylate (1.4 g, 4.9 mmol) was dissolved in methanol (12 mL), and a 5 M aqueous sodium hydroxide solution (10 mL) was added thereto, and the resulting mixture was heated under reflux for 3 hours. After the mixture was cooled to room temperature, formic acid (5 mL) was added thereto to stop the reaction. After the mixture was concentrated under reduced pressure, water (10 mL) was added thereto to suspend the resulting residue. The precipitated solid was collected by filtration and washed 3 times with water. The obtained solid was dried under reduced pressure, whereby 4-methyl-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxylic acid (1.1 g, 83%) was obtained as a solid. The thus obtained solid was suspended in dichloromethane (10 mL), oxalyl chloride (0.86 mL, 10 mmol) was added thereto, and the resulting mixture was stirred at room temperature for 2 hours. After the mixture was concentrated under reduced pressure, the residue was dissolved in tetrahydrofuran (10 mL), and 4-(methylsulfonyl)aniline hydrochloride (1.0 g, 4.9 mmol) and N,N-diisopropylethylamine (2.8 mL, 16 mmol) were sequentially added to the solution, and the resulting mixture was heated under reflux for 18 hours. After the mixture was cooled to room temperature, the solvent was distilled off under reduced pressure, and acetonitrile (10 mL) and 3 M hydrochloric acid (100 mL) were added to the residue. A precipitated solid was triturated, collected by filtration and washed with water, and then, dried under reduced pressure, whereby 4-methyl-N-[4-(methylsulfonyl) phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide (1.4 g, 89%) was obtained as a solid.
    1H-NMR (400 MHz, DMSO-d6) δ11.34 (1H, brs,), 9.89 (1H, s), 7.97 (2H, d, J = 6.6 Hz), 7.87-7.81 (3H, m), 7.73 (1H, t, J = 7.4 Hz), 7.65-7.61 (2H, m), 7.44 (1H, d, J = 7.8 Hz), 3.15 (3H, s), 2.01 (3H, s).
  • Sodium hydride (0.12 g, 3 mmol, 60% dispersion in mineral oil) was dissolved in N,N-dimethylformamide (1.5 mL), and 4-methyl -N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide (0.47 g, 1.1 mmol) was added thereto, and then, the resulting mixture was stirred at room temperature for 30 minutes. Then, 1,3,2-dioxathiolane-2,2-dioxide (0.14 g, 1.2 mmol) was added thereto, and the resulting mixture was stirred at room temperature. After 1 hour, sodium hydride (40 mg, 1.0 mmol, oily, 60%) was added thereto again, and the resulting mixture was stirred for 30 minutes. Then, 1,3,2-dioxathiolane-2,2-dioxide (12 mg, 0.11 mmol) was added thereto, and the resulting mixture was stirred at room temperature for 1 hour. After the mixture was concentrated under reduced pressure, methanol (5 mL) was added to the residue and insoluble substances were removed by filtration, and the filtrate was concentrated again. To the residue, tetrahydrofuran (2 mL) and 6 M hydrochloric acid (2 mL) were added, and the resulting mixture was stirred at 60°C for 16 hours. The reaction was cooled to room temperature, and then dissolved in ethyl acetate, and washed with water and saturated saline. The organic layer was dried over anhydrous sodium sulfate and filtered. Then, the filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (ethyl acetate), whereby the objective compound (0.25 g, 48%) was obtained.
    1H-NMR (400 MHz, CDCl3) δ: 7.89-7.79 (m, 6H), 7.66-7.58 (m, 2H), 7.49 (s, 1H), 7.36 (d, 1H, J = 7.4Hz), 3.81-3.63 (m, 4H), 3.05 (s, 3H), 2.08 (s, 3H).
    HR-MS (ESI) calcd for C22H22F3N2O4S [M+H]+, required m/z: 467.1252, found: 467.1246.
    Anal. calcd for C22H21F3N2O4S: C, 56.65; H, 4.54; N, 6.01; F, 12.22; S, 6.87. found: C, 56.39; H, 4.58; N, 5.99; F, 12.72; S, 6.92.

(Example 4)

Optical Resolution of Compound of Example 3

  • Resolution was performed 4 times in the same manner as in Example 2, whereby 74 mg of Isomer C was obtained as a solid from a fraction containing Isomer C (tR = 10 min), and 71 mg of Isomer D was obtained as a solid from a fraction containing Isomer D (tR = 11 min).
  • Isomer C: (+)-1-(2-hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide
    [α]D 21: +7.1° (c = 1.0, EtOH) .
    1H-NMR (400 MHz, CDCl3) δ: 7.91 (s, 1H), 7.87-7.79 (m, 5H), 7.67-7.58 (m, 2H), 7.51 (s, 1H), 7.35 (d, 1H, J = 7.0 Hz), 3.78-3.65 (m, 4H), 3.05 (s, 3H), 2.07 (s, 3H).
    HR-MS (ESI) calcd for C22H22F3N2O4S [M+H]+, required m/z: 467.1252, found: 467.1260.
    Retention time: 4.0 min.
  • Isomer D: (-)-1-(2-hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide
    [α]D 21: -7.2° (c = 1.1, EtOH) .
    1H-NMR (400 MHz, CDCl3) δ: 7.88-7.79 (m, 6H), 7.67-7.58 (m, 2H), 7.50 (s, 1H), 7.36 (d, 1H, J = 7.5 Hz), 3.79-3.65 (m, 4H), 3.05 (s, 3H), 2.08 (s, 3H).
    HR-MS (ESI) calcd for C22H22F3N2O4S [M+H]+, required m/z: 467.1252, found: 467.1257.
    Retention time: 4.5 min.

……………………………………………….

WO 2014168103

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2014168103

 

 Step B: pyrrole derivative compounds (A ‘)
[Of 16]
(Example 1) 2-bromo-1- [2- (trifluoromethyl) phenyl] propan-1-one
[Of 19]
 1- [2- (trifluoromethyl) phenyl] propan-1-one 75 g (370 mmol) in t- butyl methyl ether (750 mL), and I was added bromine 1.18 g (7.4 mmol). After confirming that the stirred bromine color about 30 minutes at 15 ~ 30 ℃ disappears, cooled to 0 ~ 5 ℃, was stirred with bromine 59.13 g (370 mmol) while keeping the 0 ~ 10 ℃. After stirring for about 2.5 hours, was added while maintaining 10 w / v% aqueous potassium carbonate solution (300 mL) to 0 ~ 25 ℃, was further added sodium sulfite (7.5 g), was heated to 20 ~ 30 ℃. The solution was separated, washed in the resulting organic layer was added water (225 mL), to give t- butyl methyl ether solution of the title compound and the organic layer was concentrated under reduced pressure (225 mL).
 1 H NMR (400 MHz, CDCl 3 ) delta: 1.91 (3H, D, J = 4.0 Hz), 4.97 (1H, Q, J = 6.7 Hz), 7.60 ~ 7.74 (4H, M).
(Example 2) 2-cyano-3-methyl-4-oxo-4- [2- (trifluoromethyl) phenyl] butanoate
[Of 20]
 2-bromo-1- [2- (trifluoromethyl) phenyl] propan-1 / t- butyl methyl ether solution (220 mL) in dimethylacetamide (367 mL), ethyl cyanoacetate obtained in Example 1 53.39 g (472 mmol), potassium carbonate 60.26 g (436 mmol) were sequentially added, and the mixture was stirred and heated to 45 ~ 55 ℃. After stirring for about 2 hours, 20 is cooled to ~ 30 ℃, water (734 mL) and then extracted by addition of toluene (367 mL), washed by adding water (513 mL) was carried out in the organic layer (2 times implementation). The resulting organic layer was concentrated under reduced pressure to obtain a toluene solution of the title compound (220 mL).
 1 H NMR (400 MHz, CDCl 3 ) delta: 1.33 ~ 1.38 (6H, M), 3.80 ~ 3.93 (2H, M), 4.28 ~ 4.33 (2H, M), 7.58 ~ 7.79 (4H, M).
(Example 3) 2-chloro-4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid ethyl
[Of 21]
 The 20 ~ 30 ℃ 2-cyano-3-methyl-4-oxo-4 was obtained [2- (trifluoromethyl) phenyl] butanoate in toluene (217 mL) by the method of Example 2 ethyl acetate (362 mL) Te, after the addition of thionyl chloride 42.59 g (358 mmol), cooled to -10 ~ 5 ℃, was blown hydrochloric acid gas 52.21 g (1432 mmol), further concentrated sulfuric acid 17.83 g (179 mmol) was added, and the mixture was stirred with hot 15 ~ 30 ℃. After stirring for about 20 hours, added ethyl acetate (1086 mL), warmed to 30 ~ 40 ℃, after the addition of water (362 mL), and the layers were separated. after it separated organic layer water (362 mL) was added for liquid separation, and further 5w / v% was added for liquid separation aqueous sodium hydrogen carbonate solution (362 mL).
 Subsequently the organic layer was concentrated under reduced pressure, the mixture was concentrated under reduced pressure further added toluene (579 mL), was added toluene (72 mL), and cooled to 0 ~ 5 ℃. After stirring for about 2 hours, the precipitated crystals were filtered, and washed the crystals with toluene which was cooled to 0 ~ 5 ℃ (217 mL). The resulting wet goods crystals were dried under reduced pressure at 40 ℃, the title compound was obtained (97.55 g, 82.1% yield).
 1 H NMR (400 MHz, CDCl 3 ) delta: 1.38 (3H, t, J = 7.1 Hz), 2.11 (3H, s), 4.32 (2H, Q, J = 7.1 Hz), 7.39 (1H, D, J = 7.3 Hz), 7.50 ~ 7.62 (2H, m), 7.77 (1H, d, J = 8.0 Hz), 8.31 (1H, br).
(Example 4) 4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid ethyl
[Of 22]
 Example obtained by the production method of the three 2-chloro-4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylate 97.32 g (293 mmol) in ethanol (662 mL), tetrahydrofuran (117 mL), water (49 mL), sodium formate 25.91 g (381 mmol) and 5% palladium – carbon catalyst (water content 52.1%, 10.16 g) was added at room temperature, heated to 55 ~ 65 ℃ the mixture was stirred. After stirring for about 1 hour, cooled to 40 ℃ less, tetrahydrofuran (97 mL) and filter aid (KC- flock, Nippon Paper Industries) 4.87 g was added, the catalyst was filtered and the residue using ethanol (389 mL) was washed. The combined ethanol solution was used for washing the filtrate after concentration under reduced pressure, and with the addition of water (778 mL) was stirred for 0.5 hours at 20 ~ 30 ℃. The precipitated crystals were filtered, and washed the crystals with ethanol / water = 7/8 solution was mixed with (292 mL). The resulting wet goods crystals were dried under reduced pressure at 40 ℃, the title compound was obtained (86.23 g, 98.9% yield).
 1 H NMR (400 MHz, CDCl 3 ) delta: 1.35 (3H, t, J = 7.1 Hz), 2.18 (3H, s), 4.29 (2H, M), 7.40 ~ 7.61 (4H, M), 7.77 (1H, d, J = 7.9 Hz), 8.39 (1H, br).
(Example 5) (RS) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid ethyl
[Of 23]
 N to the fourth embodiment of the manufacturing method by the resulting 4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylate 65.15 g (219 mmol), N- dimethylacetamide ( 261 mL), ethylene carbonate 28.95 g (328.7 mmol), 4- dimethylaminopyridine 2.68 g (21.9 mmol) were sequentially added at room temperature, and heated to 105 ~ 120 ℃, and the mixture was stirred. After stirring for about 10 hours, toluene was cooled to 20 ~ 30 ℃ (1303 mL), and the organic layer was extracted by adding water (326 mL). Subsequently, was washed by adding water (326 mL) to the organic layer (three times). The resulting organic layer was concentrated under reduced pressure, ethanol (652 mL) was added, and was further concentrated under reduced pressure, ethanol (130 mL) was added to obtain an ethanol solution of the title compound (326 mL).
 1 H NMR (400 MHz, CDCl 3 ) delta: 1.35 (3H, t, J = 7.1 Hz), 1.84 (1H, Broad singlet), 2.00 (3H, s), 3.63 ~ 3.77 (4H, M), 4.27 (2H , m), 7.35 ~ 7.79 (5H, m).
(Example 6) (RS) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid
[Of 24]
 Obtained by the method of Example 5 (RS) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid ethyl / ethanol (321 mL) solution in water (128.6 mL), was added at room temperature sodium hydroxide 21.4 g (519 mmol), and stirred with heating to 65 ~ 78 ℃. After stirring for about 6 hours, cooled to 20 ~ 30 ℃, after the addition of water (193 mL), and was adjusted to pH 5.5 ~ 6.5, while maintaining the 20 ~ 30 ℃ using 6 N hydrochloric acid. was added as seed crystals to the pH adjustment by a liquid (RS) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid 6.4 mg , even I was added to water (193mL). Then cooled to 0 ~ 5 ℃, again, adjusted to pH 3 ~ 4 with concentrated hydrochloric acid and stirred for about 1 hour. Then, filtered crystals are precipitated, and washed the crystals with 20% ethanol water is cooled to 0 ~ 5 ℃ (93 mL). The resulting wet product crystals were dried under reduced pressure at 40 ℃, to give the title compound (64.32 g, 95.0% yield). 1 H NMR (400 MHz, DMSO-D 6 ) delta: 1.87 (3H, s), 3.38 ~ 3.68 (4H, M), 7.43 ~ 7.89 (5H, M).
(Example 7)
(S) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid quinine salt 
(7-1) (S) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid quinine salt 
obtained by the method of Example 6 the (RS) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid 50.00 g (160 mmol), N, N- dimethylacetamide (25 mL), ethyl acetate (85 mL) was added and dissolved at room temperature (solution 1).
 Quinine 31.05 g (96 mmol) in N, N- dimethylacetamide (25 mL), ethyl acetate (350 mL), was heated in water (15 mL) 65 ~ 70 ℃ was added, was added dropwise a solution 1. After about 1 hour stirring the mixture at 65 ~ 70 ℃, and slowly cooled to 0 ~ 5 ℃ (cooling rate standard: about 0.3 ℃ / min), and stirred at that temperature for about 0.5 hours. The crystals were filtered, 5 ℃ using ethyl acetate (100 mL) which was cooled to below are washed crystals, the resulting wet product crystals was obtained and dried under reduced pressure to give the title compound 43.66 g at 40 ℃ (Yield 42.9%). Furthermore, the diastereomeric excess of the obtained salt was 98.3% de. 1 H NMR (400 MHz, DMSO-D 6 ) delta: 1.30 ~ 2.20 (10H, M), 2.41 ~ 2.49 (2H, M), 2.85 ~ 3.49 (6H, M), 3.65 ~ 3.66 (1H, M), 3.88 (3H, s), 4.82 (1H, broad singlet), 4.92 ~ 5.00 (2H, m), 5.23 ~ 5.25 (1H, m), 5.60 (1H, br), 5.80 ~ 6.00 (1H, m), 7.36 ~ 7.92 (9H, M), 8.67 (1H, D, J = 4.6 Hz) (7-2) (S)-1-(2-hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3 diastereomeric excess of the carboxylic acid quinine salt HPLC measurements (% de)  that the title compound of about 10 mg was collected, and the 10 mL was diluted with 50v / v% aqueous acetonitrile me was used as a sample solution.

 Column: DAICEL CHIRALPAK IC-3 (4.6 mmI.D. × 250 mm, 3 μm) 
mobile phase A: 0.02mol / L phosphorus vinegar buffer solution (pH 3) 
mobile phase B: acetonitrile 
solution sending of mobile phase: mobile phase A and I indicates the mixing ratio of mobile phase B in Table 1 below.
[Table 1]
  Detection: UV 237 nm 
flow rate: about 0.8 mL / min 
column temperature: 30 ℃ constant temperature in the vicinity of 
measuring time: about 20 min 
Injection volume: 5 μL 
diastereomeric excess (% de), the title compound (retention time about 12 min), was calculated by the following equation using a peak area ratio of R-isomer (retention time of about 13 min). 
% De = {[(the title compound (S body) peak area ratio) – (R body peak area ratio)] ÷ [(the title compound (S body) peak area ratio) + (R body peak area ratio)]} × 100
(Example 8)
(S) -1- (2- hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole 3-carboxamide (Compound (A)) 
(8-1) (S)-1-(2-hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole -3 – carboxylic acid 
obtained by the method of Example 7 (S) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxylic acid (8α, 9R) -6′- methoxycinnamate Conan-9-ol 40.00 g (63 mmol) in ethyl acetate (400 mL), was added 2N aqueous hydrochloric acid (100 mL) was stirred at room temperature and separated . The resulting organic layer was concentrated under reduced pressure (120 mL), and added ethyl acetate (200 mL), and further concentrated under reduced pressure to obtain a solution containing the title compound (120 mL).
(8-2) N – {[4- (methylsulfonyl) phenyl] amino} oxamic acid 2 – ((S) -3- methyl-4 – {[4- (methylsulfonyl) phenyl] carbamoyl} -2- [ 2- (trifluoromethyl) phenyl] -1H- pyrrol-1-yl) ethyl 
ethyl acetate (240 mL), was mixed tetrahydrofuran (80 mL) and oxalyl chloride 20.72 g (163 mmol), and cooled to 10 ~ 15 ℃ was. Then the resulting solution was added while keeping the 10 ~ 15 ℃ Example (8-1) and stirred for about 1 hour by heating to 15 ~ 20 ℃. After stirring, acetonitrile (120 mL) and pyridine 2.46 g (31 mmol) was added and the reaction mixture was concentrated under reduced pressure (120 mL), acetonitrile (200 mL) was added and further concentrated under reduced pressure (120 mL).
 After completion concentration under reduced pressure, acetonitrile (200 mL) was added and cooled to 10 ~ 15 ℃ (reaction 1).
 Acetonitrile (240mL), pyridine 12.39 g (157 mmol), 4- were successively added (methylsulfonyl) aniline 26.85 g (157 mmol), the reaction solution 1 was added while maintaining the 10 ~ 15 ℃, the 20 ~ 25 ℃ and the mixture was stirred and heated to about 1 hour.
 The resulting reaction solution in acetonitrile (40 mL), 2 N hydrochloric acid water (120 mL), was added sodium chloride (10.0 g) was stirred, and the layers were separated. Again, 2N aqueous hydrochloric acid to the organic layer (120 mL), was added sodium chloride (10.0 g) was stirred, and the layers were separated. After filtering the resulting organic layer was concentrated under reduced pressure (400 mL). Water (360 mL) was added to the concentrated liquid, after about 1 hour stirring, the crystals were filtered, washed with 50v / v% aqueous acetonitrile (120 mL), wet product of the title compound (undried product, 62.02 g) and obtained. 1 H NMR (500 MHz, DMSO-D 6 ) delta: 1.94 (s, 3H), 3.19 (s, 3H), 3.20 (s, 3H), 3.81 (t, 1H), 4.12 (t, 1H), 4.45 ( t, 2H, J = 5.81 Hz), 7.62 (t, 1H, J = 4.39 Hz), 7.74 (t, 2H, J = 3.68 Hz), 7.86 (dd, 3H), 7.92 (dd, 3H, J = 6.94 , 2.13 Hz), 7.97 (DD, 2H, J = 6.80, 1.98 Hz), 8.02 (DD, 2H), 10.03 (s, 1H), 11.19 (s, 1H) 
(8-3) (S)-1- (2-hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxamide (Compound (A))  ( the resulting wet product crystals 8-2), t- butyl methyl ether (200 mL), acetonitrile (40 mL), 48w / w potassium hydroxide aqueous solution (16 g) and water (200 mL) was added, I was stirred for about 2 hours at 25 ~ 35 ℃. After stirring, and the mixture is separated, the resulting organic layer was concentrated under reduced pressure (120 mL), ethanol (240 mL) was added and further concentrated under reduced pressure (120 mL). After completion concentration under reduced pressure, ethanol (36 mL), and heated in water (12 mL) was added 35 ~ 45 ℃, while maintaining the 35 ~ 45 ℃ was added dropwise water (280 mL), and was crystallized crystals. After cooling the crystal exudates to room temperature, I was filtered crystal. Then washed with crystals 30v / v% aqueous ethanol solution (80 mL), where it was dried under reduced pressure at 40 ℃, the title compound was obtained in crystalline (26.26 g, 89.7% yield). Moreover, the enantiomers of the resulting crystals was 0.3%. 
1 H NMR (400 MHz, CDCl 3 ) delta: 1.74 (1H, Broad singlet), 2.08 (3H, s), 3.04 (3H, s), 3.63 ~ 3.80 (4H, M), 7.36 (1H, D, J = 7.2 Hz), 7.48 (1H, s), 7.58 ~ 7.67 (2H, M), 7.77 ~ 7.90 (6H, M). 
(8-4) (S)-1-(2-hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole -3- HPLC method for measuring the amount enantiomer carboxamide (%)  and collected the title compound of about 10 mg is, what was the 10 mL was diluted with 50v / v% aqueous acetonitrile to obtain a sample solution.
see
(Example 12) (S) -1- (2- hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole 3-carboxamide (Compound (A)) Preparation of 2 
(12-1) (S)-1-(2-hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H – pyrrole-3-carboxylic acid 
obtained by the method of Example 7 (S) -1- (2- hydroxyethyl) -4-methyl-5- [2- (trifluoromethyl) phenyl] -1H- pyrrole 3-carboxylic acid (8α, 9R) -6′- methoxycinnamate Conan-9-ol 10.00 g (16 mmol) in t- butyl methyl ether (90 mL), water (10 mL) 36w / w% aqueous hydrochloric acid ( 5 mL) was added and stirring at room temperature and separated. The resulting organic layer was concentrated under reduced pressure (30 mL), was added ethyl acetate (50 mL), and further concentrated under reduced pressure to obtain a solution containing the title compound (30 mL). 
(12-2) N – {[4- (methylsulfonyl) phenyl] amino} oxamic acid 2 – ((S) -3- methyl-4 – {[4- (methylsulfonyl) phenyl] carbamoyl} -2- [ 2- (trifluoromethyl) phenyl] -1H- pyrrol-1-yl) ethyl 
ethyl acetate (50 mL), was mixed with tetrahydrofuran (20 mL) and oxalyl chloride 5.18 g (41 mmol), and cooled to 0 ~ 5 ℃ was.Then the resulting solution was added in Examples while maintaining the 0 ~ 5 ℃ (12-1), and the mixture was stirred for 6 hours at 0 ~ 10 ℃. After stirring, acetonitrile (30 mL) and pyridine 0.62 g (8 mmol) was added and the reaction mixture was concentrated under reduced pressure (30 mL), acetonitrile (50 mL) was added, and further concentrated under reduced pressure (30 mL).
 After concentration under reduced pressure end, is added acetonitrile (10 mL) and oxalyl chloride 0.10 g (1 mmol), and cooled to 0 ~ 5 ℃ (reaction 1).
 Acetonitrile (30mL), pyridine 3.15 g (40 mmol), 4- were successively added (methylsulfonyl) aniline 6.71 g (39 mmol), the reaction solution 1 was added while maintaining the 10 ~ 15 ℃, the 20 ~ 25 ℃ and the mixture was stirred and heated to about 1 hour.
 Insolubles from the resulting reaction solution was filtered, washed with acetonitrile (10 mL), and stirred for about 2 hours the addition of water (15 mL), followed by dropwise addition of water (75 mL) over about 1 hour . After about 1 hour stirring the suspension was filtered crystals were washed with 50v / v% aqueous acetonitrile (20 mL), wet product of the title compound (undried product, 15.78 g) to give a. 1 H NMR (500 MHz, DMSO-D 6 ) delta: 1.94 (s, 3H), 3.19 (s, 3H), 3.20 (s, 3H), 3.81 (t, 1H), 4.12 (t, 1H), 4.45 ( t, 2H, J = 5.81 Hz), 7.62 (t, 1H, J = 4.39 Hz), 7.74 (t, 2H, J = 3.68 Hz), 7.86 (dd, 3H), 7.92 (dd, 3H, J = 6.94 , 2.13 Hz), 7.97 (DD, 2H, J = 6.80, 1.98 Hz), 8.02 (DD, 2H), 10.03 (s, 1H), 11.19 (s, 1H) 
(12-3) (S)-1- (2-hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxamide (Compound (A))  ( the resulting wet product crystals 12-2), t- butyl methyl ether (50 mL), acetonitrile (10 mL), 48w / w potassium hydroxide aqueous solution (4 g) and water (50 mL) was added, 15 I was about 2 hours of stirring at ~ 25 ℃. After stirring, and the mixture is separated, the resulting organic layer was concentrated under reduced pressure (30 mL), was added ethanol (60 mL), was further concentrated under reduced pressure (30 mL). After completion concentration under reduced pressure, ethanol (14 mL), after addition of water (20 mL), was added a seed crystal, and was crystallized crystals. After dropwise over about 1 hour water (50 mL), and about 1 hour stirring, and crystals were filtered off. Then washed with crystals 30v / v% aqueous ethanol solution (10 mL), where it was dried under reduced pressure at 40 ℃, the title compound was obtained in crystal (6.36 g, 87.0% yield). Moreover, the enantiomers of the resulting crystals was 0.05%. Enantiomers amount, I was measured by the method of (Example 8-4). 1 H NMR (400 MHz, CDCl 3 ) delta: 1.74 (1H, Broad singlet), 2.08 (3H, s), 3.04 (3H, s), 3.63 ~ 3.80 (4H, M), 7.36 (1H, D, J = 7.2 Hz), 7.48 (1H, s), 7.58 ~ 7.67 (2H, m), 7.77 ~ 7.90 (6H, m).

………………………………………………

 

Patent literature

Patent Document 1: International Publication WO2006 / 012642 (US Publication US2008-0234270) 
Patent Document 2: International Publication WO2008 / 056907 (US Publication US2010-0093826) 
Patent Document 3: Pat. No. 2,082,519 JP (US Patent No. 5,616,599 JP) 
Patent Document 4: Pat. No. 1,401,088 JP (US Pat. No. 4,572,909) 
Patent Document 5: US Pat. No. 3,025,292

Angiotensin II receptor 桔抗 agent

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015012205&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=FullText

Angiotensin II receptor 桔抗 agent used as the component (A), olmesartan medoxomil, olmesartan cilexetil, losartan, candesartan cilexetil, valsartan, biphenyl tetrazole compounds such as irbesartan, biphenyl carboxylic acid compounds such as telmisartan, eprosartan, agile Sultan, and the like, preferably, a biphenyl tetrazole compound, more preferably, olmesartan medoxomil, is losartan, candesartan cilexetil, valsartan or irbesartan, particularly preferred are olmesartan medoxomil, losartan or candesartan cilexetil, Most preferably, it is olmesartan medoxomil.
 Olmesartan medoxomil, JP-A-5-78328, US Patent No. 5,616,599 
is described in Japanese or the like, its chemical name is (5-methyl-2-oxo-1,3-dioxolen-4-yl ) methyl 4- (1-hydroxy-1-methylethyl) -2-propyl-1 – in [2 ‘(1H- tetrazol-5-yl) biphenyl-4-ylmethyl] imidazole-5-carboxylate, Yes, olmesartan medoxomil of the present application includes its pharmacologically acceptable salt.
Olmesartan.pngOLMESARTAN
 Losartan (DUP-753) is, JP 63-23868, is described in US Patent No. 5,138,069 JP like, and its chemical name is 2-butyl-4-chloro-1- [2 ‘ – The (1H- tetrazol-5-yl) biphenyl-4-ylmethyl] -1H- is imidazol-5-methanol, application of losartan includes its pharmacologically acceptable salt (losartan potassium salt, etc.).
Skeletal formula
 LOSARTAN
 Candesartan cilexetil, JP-A-4-364171, EP-459136 JP, is described in US Patent No. 5,354,766 JP like, and its chemical name is 1- (cyclohexyloxycarbonyloxy) ethyl-2 ethoxy-1- [2 ‘one (1H- tetrazol-5-yl) -4-Bife~eniru ylmethyl] -1H- benzimidazole-7-carboxylate is a salt application of candesartan cilexetil, which is a pharmacologically acceptable encompasses.
 Valsartan (CGP-48933), the JP-A-4-159718, are described in EP-433983 JP-like, and its chemical name, (S) -N- valeryl -N- [2 ‘- (1H- tetrazol – It is a 5-yl) biphenyl-4-ylmethyl) valine, valsartan of the present application includes its pharmacologically acceptable ester or a pharmacologically acceptable salt thereof.
 Irbesartan (SR-47436), the Japanese Patent Publication No. Hei 4-506222, is described in JP WO91-14679 publication, etc., its chemical name, 2-N–butyl-4-spiro cyclopentane-1- [2′ The (tetrazol-5-yl) biphenyl-4-ylmethyl] -2-imidazoline-5-one, irbesartan of the present application includes its pharmacologically acceptable salts.
 Eprosartan (SKB-108566) is described in US Patent No. 5,185,351 JP etc., the chemical name, 3- [1- (4-carboxyphenyl-methyl) -2-n- butyl – imidazol-5-yl] The 2-thienyl – methyl-2-propenoic acid, present in eprosartan, the carboxylic acid derivatives, pharmacologically acceptable ester or a pharmacologically acceptable salt of a carboxylic acid derivative (eprosartan mesylate, encompasses etc.).
 Telmisartan (BIBR-277) is described in US Patent No. 5,591,762 JP like, and its chemical name is 4 ‘- [[4 Mechiru 6- (1-methyl-2-benzimidazolyl) -2 – is a propyl-1-benzimidazolyl] methyl] -2-biphenylcarboxylic acid, telmisartan of the present application includes its carboxylic acid derivative, a pharmacologically acceptable ester or a pharmacologically acceptable salt thereof of carboxylic acid derivatives .
 Agile Sultan, is described in Patent Publication No. 05-271228 flat JP, US Patent No. 5,243,054 JP like, and its chemical name is 2-ethoxy-1 {[2 ‘- (5-oxo-4,5-dihydro 1,2,4-oxadiazole-3-yl) biphenyl-4-yl] methyl} -1H- benzo [d] imidazole-7-carboxylic acid (2-Ethoxy-1 {[2 ‘- (5- oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl) biphenyl-4-yl] is a methyl} -1H-benzo [d] imidazole-7-carboxylic acid).

AMG 925


AMG 925

AMG 925

1401033-86-0

2-Hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone

2-Hydroxy-l-(2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido [4′,3 ‘ :4,5] pyrrolo [2,3-d] pyrimidin-2-yl)amino)-7,8-dihydro-l ,6- naphthyridin-6(5H)-yl)ethanone

2-Hydroxy-1-(2-((9-((1R,4R)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone (AMG 925)

FLT3/CDK4 inhibitor,potent and selective

AMG 925 is a dual kinase inhibitor of FLT3 and CDK4 with IC50 value of 1 nM and 3 nM, respectively

C26H29N7O2., 471.55

Amgen Inc.   Innovator

 

BY
SECTION 1
STEP A
STEP B
STEP C
STEP D
9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-amine

COUPLER 1

tert-butyl 2-chloro-7,8-dihydro-l,6-naphthyridine-6(5H)-carboxylate
STEP E
tert-butyl 2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido [4′,3 ‘ :4,5] pyrrolo [2,3-d] pyrimidin-2-yl)amino)-7,8-dihydro-l ,6- naphthyridine-6(5H)-carboxylate
STEP F
Figure imgf000129_0001 COMPD 1
9-((l r,4r)-4-methylcyclohexyl)-N-(5,6,7,8-tetrahydro- l,6-naphthyridin-2-yl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-amine (1)
SECTION B
COUPLER2
2,5-dioxopyrrolidin-l-yl 2-acetoxyacetate
STEP G
2-(2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido [4′,3 ‘ :4,5] pyrrolo [2,3-d] pyrimidin-2-yl)amino)-7,8-dihydro-l ,6- naphthyridin-6(5H)-yl)-2-oxoethyl acetate
STEP H
Figure imgf000135_0001 AMG 925
 STEP I

AMG 925 is a potent, selective, and orally available FLT3/CDK4 dual inhibitor. It also inhibits CDK6 potently in kinase assay. In acute myeloid leukemia (AML) cell lines MOLM13 and Mv4-11, AMG 925 inhibits cell growth (IC50 values of 19nM and 18nM, respectively) through inhibiting P-FLT3 and P-STAT5 and inducing apoptosis. FLT3 mutants cause resistance to the current FLT3 inhibitors. AMG 925 is reported to inhibit cell growth in AML cells with FLT3 mutants FLT3-D835Y and FLT3-D835V. In AML tumor –bearing mice, administration of AMG 925 shows inhibition of P-STAT5 and P-RB as well as cell growth both in subcutaneous MOLM13 xenograft tumor model and systemic MOLM13-Luc xenograft tumor model. AMG 925 is also reported to have antitumor activity in a dose-dependent manner in theRB-positive Colo205 colon adenocarcinoma xenograft model

 

AMGEN

cute myeloid leukemia (AML) represents a significant unmet medical need. It is a hematological malignancy characterized by a block in differentiation and aberrant proliferation of the myeloid lineage of hematopoietic progenitor cells. There are approximately 13,000 new cases and 9,000 deaths per year in the United States. The survival rate is 25-70% in patients younger than 60 years and 5-15% in older patients, with worse outcomes in patients with poor risk cytogenetics. Current standard of care treatment is daunorubicin and cytarabine chemotherapy with induction and consolidation phases. Bone marrow stem cell transplant is also used for treating AML in younger patients.

Cyclin-dependent kinases (CDKs) are a family of serine/ threonine protein kinases playing important cellular functions. The cyclins are the regulatory subunits that activate the catalytic CDKs. CDKl/Cyclin B 1 , CDK2/Cyclin A, CDK2/Cyclin E, CDK4/Cyclin D, CDK6/Cyclin D are critical regulators of cell cycle progression. CDKs also regulate transcription, DNA repair, differentiation, senescence and apoptosis (Morgan, D. O., Annu. Rev. Cell. Dev. Biol., 13:261-291 (1997)).

Small molecule inhibitors of CDKs have been developed to treat cancer

(de Career, G. et al., Curr. Med. Chem., 14:969-85 (2007)). A large amount of genetic evidence supports that CDKs, their substrates or regulators have been shown to be associated with many human cancers (Malumbres, M. et al, Nature Rev. Cancer, 1 :222- 231 (2001)). Endogenous protein inhibitors of CDKs including p 16, p21 and p27 inhibit CDK activity and their overexpression results in cell cycle arrest and inhibition of tumor growth in preclinical models (Kamb, A., Curr. Top. Microbiolo. Immunol., 227: 139- 148 (1998)).

Small molecule inhibitors of CDKs may also be used to treat variety of other diseases that result from aberrant cell proliferation, including cardiovascular disorders, renal diseases, certain infectious diseases and autoimmune diseases. Cell proliferation pathways including genes involved in the cell cycle Gl and S phase checkpoint (p53, pRb, pi 5, pi 6, and Cyclins A, D, E, CDK 2 and CDK4) have been associated with plaque progression, stenosis and restenosis after angioplasty. Over- expression of the CDK inhibitor protein p21 has been shown to inhibit vascular smooth muscle proliferation and intimal hyperplasia following angioplasty (Chang, M. W. et al., J. Clin. Invest, 96:2260 (1995); Yang, Z-Y. et al., Proc. Natl. Acad. Sci. (USA) 93:9905 (1996)). A small molecule CDK2 inhibitor CVT-313 (Ki = 95 nM) was shown to cause significant inhibition of neointima formation in animal models (Brooks, E. E. et al., J. Biol. Chem., 272:29207-2921 1 (1997)). Disregulation of cell cycle has been associated with polycystic kidney diseases, which are characterized by the growth of fluid-filled cysts in renal tubules. Treatment with small molecule inhibitors of CDKs yielded effective arrest of cystic disease in mouse models (Bukanov, N. O., et al., Nature, 4444:949-952 (2006)).

Infection by a variety of infectious agents, including fungi, protozoan parasites such as Plasmodium falciparum, and DNA and RNA viruses may be treated with CDK inhibitors. CDKs have been shown to be required for replication of herpes simplex virus (HSV) (Schang, L. M. et al., J. Virol., 72:5626 (1998)). Synovial tissue hyperplasia plays important roles in the development of rheumatoid arthritis; inhibition of synovial tissue proliferation may suppress inflammation and prevent joint destruction. It has been shown that over-expression of CDK inhibitor protein pl6 inhibited synovial fibroblast growth (Taniguchi, K. et al., Nat. Med., 5:760-767 (1999)) and joint swelling was substantially inhibited in animal arthritis models.

Selective inhibitors of some CDKs may also be used to protect normal untransformed cells by inhibiting specific phases of cell cycle progression (Chen, et al., J. Natl. Cancer Institute, 92: 1999-2008 (2000)). Pre-treatment with a selective CDK inhibitor prior to the use of a cytotoxic agent that inhibits a different phase of the cell cycle may reduce the side effects associated with the cytotoxic chemotherapy and possibly increase the therapeutic widow. It has been shown that induction of cellular protein inhibitors of CDKs (pi 6, p27 and p21) conferred strong resistance to paclitaxel- or cisplatin-mediated cytotoxicity on the inhibitor-responsive cells but not on the inhibitor-unresponsive cells (Schmidt, M, Oncogene, 2001 20:6164-71).

CDK4 and CDK6 are two functionally indistinguishable cyclin D dependent kinases. They are widely expressed with high levels of expression observed in cells of hematopoeitic lineage (CDK4/6 will be used throughout this document to reference both CDK4 and CDK6). CDK4/6 promotes Gl-S transition of the cell cycle by phosphorylating the retinoblastoma protein (Rb). CDK4 and CDK6 single knockout mice are viable and double knockout mice die around birth with defective

hematopoiesis (Satyanarayana, A. et al., Oncogene, 28:2925-39 (2009); Malumbres, M. et al., Cell, 1 18:493-504 (2004)). Strong evidence supports a significant involvement of the cyclin D-CDK4-pl6INK4A-Rb pathway in cancer development (Malumbres, M. et al., Nature Rev. Cancer, 1 :222-31 (2001)). Rb negatively regulates the cell cycle at Gl by sequestering E2F proteins that are required for initiation of S phase, p 1 is a key member of the ΓΝΚ4 family of CDK4/6 cellular inhibitors. The genes for Rb and pl6INK4A are tumor suppressors that are often deleted or silenced in cancer cells.

Additionally CDK4, CDK6 and cyclin D are reported to be amplified in hematologic malignancies and solid tumors. The importance of this pathway in oncogenesis is further supported by the finding that depletion or inactivation of CDK4 inhibits tumor growth in mouse tumor models (Yu, Q. et al., Cancer Cell, 9:23-32 (2006); Puyol, M. Cancer Cell, 18:63-73 (2010)). Rb and p 16^^ are rarely deleted in AML. However, the plS1^^ gene, another member of the ΓΝΚ4 family, has been reported to be down regulated by hypermethylation in up to 60% of AML (Naofumi, M. et al., Leukemia Res., 29:557-64 (2005); Drexler, H. G. Leukemia, 12:845-59 (1998); Herman, J. G. et al., Cancer Res., 57:837-41 (1997)), suggesting a possible critical role for CDK4/6 in AML cells.

FLT3 (Fms-like tyrosine kinase 3, FLK2) is a class III receptor tyrosine kinase. It is activated by the FLT3 ligand (FL) and signals through the PI3K, RAS, and JAK/STAT pathways (Scholl C. et al., Semin. Oncol., 35:336-45 (2008); Meshinchi S. et al., Clin. Cancer Res., 15:4263-9 (2009)). FLT3 plays a role in early hematopoiesis and FLT3 deficient mice have reduced numbers of progenitors of multiple lymphoid lineages (Mackarehtschian K, et al., Immunity, 3: 147-61 (1995). Activating mutations in FLT3 are found in approximately 30% of AML patients, representing the most frequent genetic alteration in the disease. About 75% of the activating mutations are internal tandem duplications (ITD) and 25% are point mutations in the activation loop of the kinase domain.

The most frequently identified activating point mutation is D835Y (Yamamoto et al., Blood, 97(8): 2434-2439 (2001)). However, mutations have also been found at N841I (Jiang, J. et al., Blood, 104(6): 1855-1858 (2004)) and Y842C (Kindler et al., Blood, 105(1): 335-340 (2005)). Additional point mutations have been identified in the juxtamembrane domain and kinase domain, although these have been shown to result in lower transforming potential (Reindel et al., Blood 107(9): 3700- 3707 (2006)).

Murine bone marrow transplanted with a retrovirus expressing the

FLT3-ITD has been shown to result in the production of a lethal myeloproliferative disease in mice (Kelly et al., Blood 99: 310-318 (2002)) characterized by leukocytosis consisting of mature neutrophils. This disease did not show a block in differentiation as seen in human AML suggesting that FLT3 mutations confer a proliferative or survival advantage to the cells. Additional oncogene mutation producing a block in

differentiation such as AML1/ETO is hypothesized to be required to produce disease that is more similar to human AML.

A number of FLT3 inhibitors have been tested in clinical trials.

Although they have shown initial clinical responses in AML, the responses observed were transient and resistance can develop rapidly (Weisberg, E. et al., Oncogene, 29:5120-34 (2010)). The major resistance mechanism appears to be through the acquisition of secondary mutations in FLT3, which may interfere with the binding of FLT3 inhibitors to the FLT3 receptor (Weisberg, E. et al., Oncogene, 29:5120-34 (2010); Chu, S. H. et al., Drug Resist. Update, 12:8-16 (2009)). One such resistance mutation (N676K) was identified in a patient at the time of clinical relapse while on multi-kinase FLT3 inhibitor midostaurin (PKC412) monotherapy (Heidel, F. et al., Blood, 107:293-300 (2006)). Combinations of FLT3 inhibitors with chemotherapy are being tested in clinical trials despite the recognition that chemotherapy is poorly tolerated. Additional possible mechanisms for lack of durable responses include inadequate target coverage (Pratz, K. W., et al., Blood, 139:3938-46 (2009)) and protection of AML cells in the bone marrow where stromal growth factors may provide proliferative signals in addition to FLT3 activation (Tarn, W. F. et al., Best Pract. Res. Clin. Haematol., 21 : 13-20 (2008)). Inhibitors with combined FLT3 and CDK4/6 inhibitory activities are novel and may prove beneficial in treating various cancers including, but not limited to, AML.

Fused tricyclic pyridine, pyrimidine, and triazine compounds useful for treating diseases mediated by CDK4 are disclosed in WO 2009/085185, published on July 9, 2009, which is hereby incorporated by reference in its entirety and for all purposes as if fully set forth herein. Various gem-disubstituted and spirocyclic compounds useful for treating diseases mediated by CDK4 are disclosed in WO 2009/0126584, published on October 15, 2009, which is hereby incorporated by reference in its entirety and for all purposes as if fully set forth herein.

A continued need exists for new compounds that can be used to modulate CDK4, CDK6, and/or FLT3 and can be used to treat various disease conditions associated with these kinases. The compounds of the present invention provide significant improvements in inhibition in one or more of these kinases and have properties making them excellent therapeutic candidates.

………………………

PATENT WO2012129344

http://www.google.com/patents/WO2012129344A1?cl=en

[01 16] In some embo f Formula I, the compound is

SCHEME 3

 

R1′-CI

3G …………………………………………………………..3H

 

Example 1. 9-((lr,4r)-4-Methylcyclohexyl)-N-(5,6,7,8-tetrahydro-1 ,6-naphthyridin-2-yl)-9H-py 3-d] pyrimidin-2-amine

Figure imgf000125_0001 KEY INTERMEDIATE 1
……………………………………..SECTION 1 BELOW
STEP A

4-Chloropyrimidine-2-amine (commercially available from Sigma-Aldrich, St. Louis, MO) (1000 g, 7.72 mol, 1.0 eq), trans- 4-methylcyclohexylamine hydrochloride (commercially available from TCI America, M1780) (1500 g, 10.03 mol, 1.3 eq) and TEA (3.23 L, 23.2 mol, 3.0 eq) were mixed together in n-butanol (8 L). The reaction mixture was heated at reflux for 36 hours and monitored using LCMS. Upon completion, the reaction mixture was cooled to room temperature, diluted with water (8 L) and extracted with EtOAc (2 x 10 L). The organic layers were combined, dried over Na2S04, and concentrated under reduced pressure to give the title compound (1770 g) which was us

STEP B

Synthesis of 5-iodo-A^-((lr,4r)-4-methylcyclohexyl)pyridine-2,4- diamine. N4-((lr,4r)-4-Methylcyclohexyl)pyridine-2,4-diamine (1770 g, 8.58 mol, 1.0 eq) was dissolved in anhydrous DMF (8 L). To this solution under N2 atmosphere at 10 °C was added NIS (1.93 kg, 8.58 mol, 1.0 eq) in portions over 10 minutes. Upon completion of the addition, the reaction mixture was stirred at room temperature for 2 hours. The reaction was monitored using LCMS. Upon completion, the reaction mixture was cooled using an ice bath, quenched with saturated aqueous sodium carbonate (5 L) and extracted with EtOAc (2 x 15 L). The combined organic extracts were washed with saturated aqueous sodium carbonate (2 x 5 L), water (3 x 2 L), dried over Na2S04, and concentrated under reduced pressure. The residue was purified using column chromatography eluting with 25% to 40% EtOAc in hexanes to provide the title compound (1.47 kg, 57% over two steps). ^-NMR (300 MHz, DMSO-d6) δ ppm 0.85 (3H, d, J= 7.2 Hz), 0.98 (1H, dd, J= 12.9, 2.7 Hz), 1.41 – 1.27 (3H, m), 1.66 (2H, d, J = 12.3 Hz), 1.78 (2H, d, J= 12.3 Hz), 3.85 (1H, m), 5.48 (1H, d, J= 8.1 Hz), 6.16 (2H, br s), 7.86

STEPC

Synthesis of 5-(3-fluoropyridin-4-yl)-N -((lr,4r)-4- methylcyclohexyl)pyrimidine-2,4-diamine. To a solution of 2,2,6,6- tetramethylpiperidine (commercially available from Sigma-Aldrich, St. Louis, MO) (997 mL, 5.87 mol, 3 eq) in anhydrous THF (6 L) under N2 atmosphere at 0 °C, was added n-BuLi (2.5 M in hexanes, 2.35 L, 5.87 mol, 3 eq) via an addition funnel over 30 minutes. Upon completion of the addition, the reaction mixture was stirred at 0 °C for 1 hour. The reaction mixture was cooled to -74 °C (acetone/ dry ice bath) and a solution of 3-fluoropyridine (commercially available from Sigma-Aldrich, St. Louis, MO) (561 g, 5.773 mol, 2.95 eq) in anhydrous THF (500 mL) was added over 15 minutes keeping the temperature below -63 °C. Upon completion of the addition, the reaction mixture was stirred at -74 °C for an additional 2 hours. A solution of ZnBr2 (1422 g, 6.32 mol, 3.22 eq) in anhydrous THF (3 L) was then added dropwise over 35 minutes keeping the temperature below -60 °C. Upon completion of the addition, the cold bath was removed and the reaction mixture was allowed to warm to room temperature. Then 5- iodo-N4-((lr,4r)-4-methylcyclohexyl)pyridine-2,4-diamine (650 g, 1.95 mol, 1.0 eq) was added in one portion followed by Pd(PPh3)4 (113 g, 97.8 mmol, 0.05 eq). The reaction mixture was heated at reflux overnight and monitored using LCMS. Upon completion, the reaction mixture was cooled to room temperature, quenched with saturated aqueous NaHC03 (6 L) and extracted with EtOAc (10 L x 2). The organic extracts were washed with saturated NaHC03 (2.5 L x 2) and brine (2.5 L), and were then concentrated under vacuum. The residue was dissolved in 2N HC1 (2.5 L) and washed with DCM (1.25 L x 3). The aqueous phase was adjusted to pH 10-12 by addition of aqueous 4N NaOH and extracted with DCM (1.5 L x 3). The organic extracts were washed with water (1.25 L x 2), dried and concentrated to give the title compound (540 g, 92%). ^-NMR (300 MHz, DMSO-d6) δ ppm 0.85 (3H, d, J= 7.2 Hz), 0.98 (1H, dd, J= 12.9, 2.7 Hz), 1.30 – 1.18 (3H, m), 1.64 (2H, d, J= 12.3 Hz), 1.74 (2H, d, J= 1 1.7 Hz), 3.96 (1H, m), 5.00 (1H, d, J= 8.4 Hz), 6.24 (2H, br s), 7.35 (1H, dd, J= 6.6, 4.4 Hz), 7.58 (1H, s), 8.37 (1H, d, J= 4.8 Hz), 8.50 (1H, d, J= 6.6 Hz) ppm.

 

STEPD

Synthesis of 9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-amine. To a solution of 5-(3- fluoropyridin-4-yl)-N4-((lr,4r)-4-methylcyclohexyl)pyrimidine-2,4-diamine (854 g, 2.84 mol, 1.0 eq) in anhydrous 1 -methyl-2-pyrrolidinone (8 L) under N2 atmosphere at room temperature, was added LiHMDS (1.0 M in toluene, 8.5 L, 8.5 mol, 3.0 eq) over 30 minutes. Upon completion of the addition, the reaction mixture was heated at 90 °C overnight and monitored using LCMS. Upon completion, the reaction mixture was cooled to room temperature, quenched with ice cold water (10 L) and extracted with EtOAc (12 L). The organic phase was washed with saturated aqueous NaHC03 (4 L x 2), and water (2 L x 3). The aqueous layers were combined and back extracted with EtOAc (15 L x 2). The organic layers were combined, dried over Na2SO/t, and concentrated under reduced pressure. The solid thus obtained was suspended in DCM (2.5 L) and agitated using a rotary evaporator for 30minutes. The solid was collected by filtration, washed with DCM and dried to afford the title compound (400 g). The mother liquor was purified by column chromatography (eluting with DCM/MeOH = 50: 1) to afford, after triturating with DCM (750 mL), additional title compound (277 g, total: 677 g, yield: 84%). ¾ NMR (300 MHz, CD3OD) δ ppm 1.02 (d, J= 6.3 Hz, 3H), 1.33-1.20 (m, 2H), 1.67-1.60 (m, 2H), 1.95-1.84 (m, 4H), 1.58-1.45 (m, 2H), 4.87-4.77 (m, 1H), 7.94 (d, J= 5.1 Hz, 1H), 8.31 (d, J= 5.1 Hz, 1H), 8.87 (s, 1H), 8.96 (s, 1H) ppm; MS m/z: 28

……………………………………

COUPLER 1

Synthesis of tert-butyl 2-chloro-7,8-dihydro-l,6-naphthyridine-6(5H)-carboxylate. To a slurry of 2-chloro-5,6,7,8-tetrahydro-l,6-naphthyridine hydrochloride (106.1 g, 517 mmol, commercially available from D-L Chiral Chemicals, ST-0143) and N,N-diisopropylethylamine (80 g, 108 mL, 621 mmol, 1.2 eq) in DCM (1 L) was added a solution of di-tert-butyl dicarbonate (119 g, 543 mmol, 1.05 eq) in

DCM (100 mL) via an addition funnel within 1 hr. The reaction mixture became a clean solution and the solution thus obtained was stirred at room temperature for an additional hour and monitored using LCMS. Upon completion, the reaction mixture was concentrated. The residue was dissolved in EtOAc (1 L) and washed with water (3 x 300 mL), washed with brine (300 mL) and dried over MgSOzt. The solvent was evaporated under vacuum to give the title compound as an off- white solid (139 g, yield: 100%). lH NMR (400MHz ,CDC13) δ ppm 1.49 (9H, s), 2.97 (2H, t, J= 5.9 Hz), 3.73 (2H, t, J= 6.0 Hz), 4.57 (2H, s), 7.17 (1H, d, J= 8.0 Hz), 7.38 (1H, d, J= 8.0 Hz) ppm;

……………………………

STEP E

Synthesis of tert-butyl 2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido [4′,3 ‘ :4,5] pyrrolo [2,3-d] pyrimidin-2-yl)amino)-7,8-dihydro-l ,6- naphthyridine-6(5H)-carboxylate. To a solution of 9-((lr,4r)-4-methylcyclohexyl)- 9H-pyrido[4′,3’:4,5]pyrrolo[2,3-d]pyrimidin-2-amine (2.81 g, lO mmol) in 1,4-dioxane (45 mL) were added tert-butyl 2-chloro-7,8-dihydro-l,6-naphthyridine-6(5H)- carboxylate (2.57 g, 9.55 mmol), 4,5-bis(diphenylphosphino)-9,9-dimethylxanene (231 mg, 0.40 mmol), and sodium t-butoxide (1.44 g, 15 mmol). Argon was bubbled through the mixture for 10 minutes. Tris(dibenzylideneacetone)dipalladium (0)(183 mg, 0.20 mmol) was added, and argon was again bubbled through the mixture for 5 minutes. The reaction mixture thus obtained was stirred at 100 °C for 3 hours whereupon HPLC-MS analysis indicated that the reaction was complete. The reaction mixture was cooled to 40 °C and diluted with DCM (90 mL) and treated with Si- triamine (functionalized silica gel, from Silicycle, FR31017TR130B) (2.8 g) overnight at room temperature. Celite® brand filter aid 545 (6 g) was added, and the mixture was filtered with a sintered glass funnel and the solid phase was rinsed with DCM (100 mL). The filtrate was concentrated to 25 mL on a rotary evaporator and diluted with a mixture of EtOAc and hexane (20 mL, 4: 1). The resulting slurry was stirred at room temperature for 5 hours. The solid was collected by filtration, washed with a mixture of EtOAc and hexane (20 mL, 1 : 1) and air dried for a few hours to provide the title compound as an off-white solid (4.90 g, 100% yield). lH NMR (500 MHz, CD2C12) δ ppm 1.06 (3H, d, J= 6.4 Hz), 1.34 – 1.22 (2H, m), 1.48 (9H, s), 1.67 (1H, br. s), 2.02 – 1.93 (4H, m), 2.63 (2H, dq, J= 3.1, 12.8 Hz), 2.88 (2H, t, J= 5.7 Hz), 3.74 (2H, t, J= 6.0 Hz), 4.57 (2H, s), 7.51 (1H, d, J= 8.6 Hz), 7.85 (1H, d, J= 5.1 Hz), 8.10 (1H, br. s), 8.42 (1H, d, J= 8.3 Hz), 8.46 (1H, d, J= 4.9 Hz), 8.97 (1H, s), 9.10 (1H, s) ppm;

…………………………

STEP F

 

1

Synthesis of 9-((l r,4r)-4-methylcyclohexyl)-N-(5,6,7,8-tetrahydro- l,6-naphthyridin-2-yl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-amine (1).

To a suspension of tert-butyl 2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amm^

6(5H)-carboxylate: 9-((lr,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3- d]pyrimidin-2-amine (4.65 g, 9.05 mmol) in MeOH (30 mL) were added concentrated HC1 (6.74 mL) and water (14 mL). The mixture thus obtained was stirred at room temperature overnight. 50% NaOH in water (4.8 mL) was added at 0 °C to the reaction mixture to adjust the pH value to 9. The precipitated yellow solid was collected by filtration, rinsed with water (25 mL) and air dried for 3 days to give the title compound (3.75 g, 100%). lH NMR (400 MHz, CDC13) δ ppm 1.07 (3H, d, J= 6.5 Hz), 1.29 – 1.25 (3H, m), 2.00 – 1.95 (3H, m), 2.02 (2H, s), 2.69 – 2.53 (2H, m), 2.89 (2H, t, J= 6.0 Hz), 3.26 (2H, t, J= 6.0 Hz), 4.04 (2H, s), 4.71 (1H, m, J= 12.8, 12.8 Hz), 7.41 (1H, d, J= 8.4 Hz), 7.84 (1H, d, J= 6.1 Hz), 7.84 (1H, d, J= 6.1 Hz), 8.03 (1H, s), 8.34 (1H, d, J= 8.4 Hz), 8.50 (1H, d, J= 5.3 Hz), 8.96 (1H, s), 9.08 (1H, s) ppm; LCMS m/z: 414 (M+l).

http://www.google.com/patents/WO2012129344A1?cl=en

SECTION 2 BELOW

SYNTHESIS OF LABEL 5 FROM 1

 

Example 5. 2-Hydroxy-l-(2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido [4′,3 ‘ :4,5] pyrrolo [2,3-d] pyrimidin-2-yl)amino)-7,8-dihydro-l ,6- naphthyridin-6(5H)-yl)ethanone

Figure imgf000134_0001 LABEL 5
…………………………
COUPLER 2

Synthesis of 2,5-dioxopyrrolidin-l-yl 2-acetoxyacetate.

A 3-neck round-bottom flask equipped with a mechanical stirrer, thermocouple and addition funnel with nitrogen inlet was charged with N-hydroxysuccinimide (commercially available from Sigma- Aldrich, St. Louis, MO) (21 1 g, 1.83 mol) and DCM (2.25 L) at room temperature, resulting in a suspension. Pyridine (178 mL, 2.2 mol) was added in one portion with no change in the internal temperature. A solution of acetoxyacetyl chloride (commercially available from Sigma-Aldrich, St. Louis, MO) (197 mL, 1.83 mol) in DCM (225 mL) was added dropwise over 60 minutes and the temperature rose to 35 °C. Stirring was continued at room temperature for 2.5 hours. The reaction mixture was washed with water (IxlL), IN HCl (2xlL) and brine (IxlL). The organic layer was concentrated under vacuum and azeotroped with toluene (IxlL) to obtain the product as a white solid (367 g, 93%). lH NMR (400MHz, CDC13) δ 4.96 (2H, s), 2.86 (4H s), 2.19 (3H, s) ppm; LCMS m/z: 238 (M+Na).

…………………………………

STEP G

Synthesis of 2-(2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido [4′,3 ‘ :4,5] pyrrolo [2,3-d] pyrimidin-2-yl)amino)-7,8-dihydro-l ,6- naphthyridin-6(5H)-yl)-2-oxoethyl acetate.

To a suspension of 9-((lr,4r)-4- methylcyclohexyl)-N-(5,6,7,8-tetrahydro-l,6-naphthyridin-2-yl)-9H- pyrido[4′,3’:4,5]pyrrolo[2,3-d]pyrimidin-2-amine (1) (827 mg, 2.0 mmol) in chloroform (10 mL) were added diisopropylethylamine (258 mg, 348 uL, 2.0 mmol) and 2,5- dioxopyrrolidin- l-yl 2-acetoxyacetate (560 mg, 2.6 mmol). The reaction mixture thus obtained was stirred at room temperature for 30 minutes whereupon the mixture became a yellow solution. HPLC-MS analysis indicated that the reaction was complete. The reaction mixture was concentrated. MeOH (5 mL) and water (6 mL) were added to form a slurry which was stirred at room temperature for 1 hour. The solid was collected by filtration to give the title compound as a light yellow solid (1.04 g, 98% yield). lH NMR (400 MHz, CDC13, rotamers) δ ppm 1.08 (3H, d, J= 6.5 Hz), 1.37 – 1.20 (2H, m), 2.03 – 1.97 (4H, m), 2.22 (3H, s), 2.69 – 2.52 (2H, m, J= 2.9, 12.8, 12.8, 12.8 Hz), 3.08 – 2.93 (2H, m), 3.75 (1H, t, J= 5.9 Hz), 3.97 (1H, t, J= 5.6 Hz), 4.59 (1H, s), ), 4.80 – 4.65 (2H, m), ), 4.90 – 4.82 (2H, m), 7.57 – 7.45 (1H, m), 7.86 (1H, d, J= 5.7 Hz), 8.21 – 8.10 (1H, m), 8.49 – 8.40 (1H, m), 8.52 (1H, d, J= 5.3 Hz), 8.

…………………………………..

STEPH

LABEL 5

Synthesis of 2-hydroxy-l-(2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido [4′,3 ‘ :4,5] pyrrolo [2,3-d] pyrimidin-2-yl)amino)-7,8-dihydro-l ,6- naphthyridin-6(5H)-yl)ethanone (5).

To a solution of 2-(2-((9-((lr,4r)-4- methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8- dihydro-l,6-naphthyridin-6(5H)-yl)-2-oxoethyl acetate (514 mg, 1.0 mmol) in DCM (7.5 mL) and MeOH (2.5 mL) was added 0.5 M sodium methoxide solution in MeOH (0.30 mL, 0.15 mmol), and the reaction mixture was stirred at room temperature for 1 hour and monitored using LCMS. Upon completion, the reaction mixture was concentrated. The residue was treated with EtOH (5 mL) and water (10 mL) to provide a solid which was collected by filtration, washed with water, and dried in a vacuum oven at 55 °C overnight to give the title compound (5) as a white solid (468 mg, 99% yield).

lH NMR (500 MHz, acetic acid-d4, 373 K) δ ppm 1.09 (3H, d, J= 6.5 Hz), 1.31-1.43 (2H, m), 1.70-1.80 (1H, m), 1.99-2.03 (2H, m), 2.06-2.13 (2H, m), 2.68 (2H, dq, J= 3.3, 12.7 Hz), 3.10 (2H, t, J= 5.4 Hz), 3.88 (2H, br. s.), 4.46 (2H, br. s.), 4.77 (2H, br. s), 4.90 (1H, tt, J= 3.9, 12.4 Hz), 7.76 (1H, d, J= 8.5 Hz), 8.33 (1H, d, J= 8.5 Hz), 8.40 (1H, d, J= 6.0 Hz), 8.63 (1H, d, J= 6.0 Hz), 9.35 (1H, s), 9.43 (1H, s) ppm; L

………………………………………………

STEP I

5                                                                                          LABEL HCI Dihydrate

[0222] Synthesis of 2-hydroxy-l-(2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido [4′,3 ‘ :4,5] pyrrolo [2,3-d] pyrimidin-2-yl)amino)-7,8-dihydro-l ,6- naphthyridin-6(5H)-yl)ethanone monohydrochloride dihydrate. To a suspension of 2-hydroxy-l-(2-((9-((lr,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3- d]pyrimidin-2-yl)amino)-7,8-dihydro-l,6-naphthyridin-6(5H)-yl)ethanone (472 mg, 1.0 mmol) in water (2 mL) was added 2 N HCI (2 mL). The mixture became a clear solution. The pH value of the solution was adjusted to 4 by addition of 2 N NaOH at 0 °C and the precipitated light yellow solid was collected by filtration. The collected solid was washed with cold water three times. The solid was dried under vacuum to give the title compound as a light yellow solid (469 mg, 92% yield).

¾ NMR (500 MHz, DMSO-d6) δ 1.02 (3H, d, J= 5.0 Hz), 1.20- 1.30 (2H, m), 1.64 (1H, m), 1.88-1.90 (4H, m), 2.59-2.66 (2H, m), 2.85-2.95 (2H, m), 3.71(1H, m), 3.83 (1H, m), 4.19-4.22 (2H, m), 4.60-4.67 (2H, m), 4.85 (1H, m), 7.75 (1H, d, J= 8.5 Hz), 8.19 (1H, d, J= 8.5 Hz), 8.55 (1H, d, J= 5.0 Hz), 8.63 (1H, d, J= 5.0 Hz), 9.47 (1H, s), 9.58 (1H, s), 10.59 (1H, br.s) ppm; LCMS m/z: 472 (M+l). Anal.

Calc: C = 57.40, H = 6.30, N = 18.02; Found: C = 57.06, H = 6.31, N = 17.92. [0223] Alternative Synthesis of Hydrochloride Salt of 2-Hydroxy-l-(2-((9-

((lr,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2- yl)amino)-7,8-dihydro-l,6-naphthyridin-6(5H)-yl)ethanone. To a suspension of 2- hydroxy- 1 -(2-((9-(( 1 r,4r)-4-methylcyclohexyl)-9H-pyrido [4′,3 ‘ :4,5]pyrrolo [2,3 – d]pyrimidin-2-yl)amino)-7,8-dihydro-l,6-naphthyridin-6(5H)-yl)ethanone (2.385 g, 5.0 mmol) in water (10 mL) was added 2N HC1 (10 mL) at 20°C. The mixture became a clear light yellow solution. The pH value of the solution was adjusted to 4 by addition of 2N NaOH through addition funnel at 0° C, and the precipitated yellow solid was collected by filtration. The resulting solid was washed with cold water three times. The solid was dried under vacuum at 50° C for two days to provide 2.49 g of the hydrochloride salt of 2-hydroxy-l-(2-((9-((lr,4r)-4-methylcyclohexyl)-9H- pyrido[4′,3’:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-l,6-naphthyridin- 6(5H)-yl)ethanone as a solid. This salt was also obtained as a hydrate.

………………

US20140163052

http://www.google.com/patents/US20140163052

Example 5

2-Hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone

Synthesis of 2,5-dioxopyrrolidin-1-yl 2-acetoxyacetate

A 3-neck round-bottom flask equipped with a mechanical stirrer, thermocouple and addition funnel with nitrogen inlet was charged with N-hydroxysuccinimide (commercially available from Sigma-Aldrich, St. Louis, Mo.) (211 g, 1.83 mol) and DCM (2.25 L) at room temperature, resulting in a suspension. Pyridine (178 mL, 2.2 mol) was added in one portion with no change in the internal temperature. A solution of acetoxyacetyl chloride (commercially available from Sigma-Aldrich, St. Louis, Mo.) (197 mL, 1.83 mol) in DCM (225 mL) was added dropwise over 60 minutes and the temperature rose to 35° C. Stirring was continued at room temperature for 2.5 hours. The reaction mixture was washed with water (1×1 L), 1N HCl (2×1 L) and brine (1×1 L). The organic layer was concentrated under vacuum and azeotroped with toluene (1×1 L) to obtain the product as a white solid (367 g, 93%). 1H NMR (400 MHz, CDCl3) δ 4.96 (2H, s), 2.86 (4H, s), 2.19 (3H, s) ppm; LCMS m/z: 238 (M+Na).

Synthesis of 2-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)-2-oxoethyl acetate

To a suspension of 9-((1r,4r)-4-methylcyclohexyl)-N-(5,6,7,8-tetrahydro-1,6-naphthyridin-2-yl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-amine (1) (827 mg, 2.0 mmol) in chloroform (10 mL) were added diisopropylethylamine (258 mg, 348 uL, 2.0 mmol) and 2,5-dioxopyrrolidin-1-yl 2-acetoxyacetate (560 mg, 2.6 mmol). The reaction mixture thus obtained was stirred at room temperature for 30 minutes whereupon the mixture became a yellow solution. HPLC-MS analysis indicated that the reaction was complete. The reaction mixture was concentrated. MeOH (5 mL) and water (6 mL) were added to form a slurry which was stirred at room temperature for 1 hour. The solid was collected by filtration to give the title compound as a light yellow solid (1.04 g, 98% yield). 1H NMR (400 MHz, CDCl3, rotamers) δ ppm 1.08 (3H, d, J=6.5 Hz), 1.37-1.20 (2H, m), 2.03-1.97 (4H, m), 2.22 (3H, s), 2.69-2.52 (2H, m, J=2.9, 12.8, 12.8, 12.8 Hz), 3.08-2.93 (2H, m), 3.75 (1H, t, J=5.9 Hz), 3.97 (1H, t, J=5.6 Hz), 4.59 (1H, s),), 4.80-4.65 (2H, m),), 4.90-4.82 (2H, m), 7.57-7.45 (1H, m), 7.86 (1H, d, J=5.7 Hz), 8.21-8.10 (1H, m), 8.49-8.40 (1H, m), 8.52 (1H, d, J=5.3 Hz), 8.98 (1H, s), 9.11 (1H, s) ppm; LCMS m/z: 514 (M+1).

Synthesis of 2-hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone (5)

To a solution of 2-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)-2-oxoethyl acetate (514 mg, 1.0 mmol) in DCM (7.5 mL) and MeOH (2.5 mL) was added 0.5 M sodium methoxide solution in MeOH (0.30 mL, 0.15 mmol), and the reaction mixture was stirred at room temperature for 1 hour and monitored using LCMS. Upon completion, the reaction mixture was concentrated. The residue was treated with EtOH (5 mL) and water (10 mL) to provide a solid which was collected by filtration, washed with water, and dried in a vacuum oven at 55° C. overnight to give the title compound (5) as a white solid (468 mg, 99% yield). 1H NMR (500 MHz, acetic acid-d4, 373 K) δ ppm 1.09 (3H, d, J=6.5 Hz), 1.31-1.43 (2H, m), 1.70-1.80 (1H, m), 1.99-2.03 (2H, m), 2.06-2.13 (2H, m), 2.68 (2H, dq, J=3.3, 12.7 Hz), 3.10 (2H, t, J=5.4 Hz), 3.88 (2H, br. s.), 4.46 (2H, br. s.), 4.77 (2H, br. s), 4.90 (1H, tt, J=3.9, 12.4 Hz), 7.76 (1H, d, J=8.5 Hz), 8.33 (1H, d, J=8.5 Hz), 8.40 (1H, d, J=6.0 Hz), 8.63 (1H, d, J=6.0 Hz), 9.35 (1H, s), 9.43 (1H, s) ppm; LCMS m/z: 472 (M+1).

Synthesis of 2-hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone monohydrochloride dihydrate

To a suspension of 2-hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone (472 mg, 1.0 mmol) in water (2 mL) was added 2 N HCl (2 mL). The mixture became a clear solution. The pH value of the solution was adjusted to 4 by addition of 2 N NaOH at 0° C. and the precipitated light yellow solid was collected by filtration. The collected solid was washed with cold water three times. The solid was dried under vacuum to give the title compound as a light yellow solid (469 mg, 92% yield). 1H NMR (500 MHz, DMSO-d6) δ 1.02 (3H, d, J=5.0 Hz), 1.20-1.30 (2H, m), 1.64 (1H, m), 1.88-1.90 (4H, m), 2.59-2.66 (2H, m), 2.85-2.95 (2H, m), 3.71 (1H, m), 3.83 (1H, m), 4.19-4.22 (2H, m), 4.60-4.67 (2H, m), 4.85 (1H, m), 7.75 (1H, d, J=8.5 Hz), 8.19 (1H, d, J=8.5 Hz), 8.55 (1H, d, J=5.0 Hz), 8.63 (1H, d, J=5.0 Hz), 9.47 (1H, s), 9.58 (1H, s), 10.59 (1H, br.s) ppm; LCMS m/z: 472 (M+1). Anal. (C26H29N7O2—HCl.2H2O) Calc: C=57.40, H=6.30, N=18.02. Found: C=57.06, H=6.31, N=17.92.

Alternative Synthesis of Hydrochloride Salt of 2-Hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl) amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl) ethanone

To a suspension of 2-hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone (2.385 g, 5.0 mmol) in water (10 mL) was added 2N HCl (10 mL) at 20° C. The mixture became a clear light yellow solution. The pH value of the solution was adjusted to 4 by addition of 2N NaOH through addition funnel at 0° C., and the precipitated yellow solid was collected by filtration. The resulting solid was washed with cold water three times. The solid was dried under vacuum at 50° C. for two days to provide 2.49 g of the hydrochloride salt of 2-hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone as a solid. This salt was also obtained as a hydrate.

………………………

J. Med. Chem., 2014, 57 (8), pp 3430–3449
DOI: 10.1021/jm500118j

2-Hydroxy-1-(2-((9-((1r,4r)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone (28)

 compound 28 as a white solid (468 mg, 99% yield).
1H NMR (500 MHz, acetic acid-d4, 373 K) δ ppm 9.43 (1 H, s), 9.35 (1 H, s), 8.63 (1H, d, J = 6.0 Hz), 8.40 (1 H, d, J = 6.0 Hz), 8.33 (1 H, d, J = 8.5 Hz), 7.76 (1 H, d, J = 8.5 Hz), 4.90 (1 H, m), 4.77 (2 H, br s), 4.46 (2 H, br s), 3.88 (2 H, br s), 3.10 (2 H, t, J = 5.4 Hz), 2.68 (2 H, dq, J = 12.7, 3.3 Hz), 2.06–2.13 (2 H, m), 1.99–2.03 (2 H, m), 1.70–1.80 (1 H, m), 1.31–1.43 (2 H, m), 1.09 (3H, d, J = 6.5 Hz).
HRMS (ESI) m/z: calculated for [M + H]+ 472.2455, found 472.2461.

 

 

…………………………

PAPER

OPRD

Chemical Process R&D, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320
Norchim S.A.S., 33 Quai d’Amont, Saint Leu d’Esserent, France 60340
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/op500367p
Abstract Image

The development of a synthetic route to manufacture the drug candidate AMG 925 on kilogram scale is reported herein. The hydrochloride salt of AMG 925 was prepared in 23% overall yield over eight steps from commercially available raw materials, and more than 8 kg of the target molecule were delivered. The synthetic route features a Buchwald–Hartwig amination using BrettPhos as ligand and conducted to afford 12 kg of product in a single batch. In addition, this work highlights the challenges associated with the use of poorly soluble process intermediates in the manufacture of active pharmaceutical ingredients. Creative solutions had to be devised to conduct seemingly routine activities such as salt removal, pH adjustment, and heavy metal scavenging due to the low solubility of the process intermediates. Finally, a slurry-to-slurry amidation protocol was optimized to allow for successful scale-up.

Manufacture of 2-Hydroxy-1-(2-((9-((1R,4R)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone (AMG 925)

AMG 925 was isolated in 91.5% yield (8.31 kg), 95.5% overall mass balance, 99.9 wt %, and 99.7 LCAP.

Mp 213–215 °C;

1H NMR (400 MHz, acetic acid-d4, mixture of two rotamers at 20 °C) 9.47–9.59 (m, 2H), 8.76 (d, 1H, J = 6 Hz), 8.55 (d, 1H, J = 6 Hz), 8.48 (d, 1H,J = 9 Hz), 7.79–7.92 (m, 1H), 4.95 (t, 1H, J = 12 Hz), 4.87 and 4.68 (2 singlets, 2H), 4.47–4.59 (m, 2H), 4.04 and 3.80 (2 triplets, 2H, J = 6 Hz), 3.03–3.17 (m, 2H), 2.65–2.82 (m, 2H), 1.96–2.15 (m, 4H), 1.77 (br s, 1H), 1.39 (q, 2H, J = 12 Hz), 1.09 (d, 3H, J = 7 Hz);

13C NMR (100 MHz, acetic acid-d4, mixture of two rotamers at 20 °C) 171.9, 171.8, 158.4, 157.8, 154.7, 149.0, 148.9, 141.6, 135.2, 132.9, 126.3, 124.1, 123.6, 117.7, 113.7, 113.6, 107.5, 107.4, 60.1, 59.9, 56.3, 43.7, 42.6, 40.5, 38.7, 34.0, 31.5, 29.8, 28.8, 28.1, 21.5.

Manufacture of 2-Hydroxy-1-(2-((9-((1R,4R)-4-methylcyclohexyl)-9H-pyrido[4′,3′:4,5]pyrrolo[2,3-d]pyrimidin-2-yl)amino)-7,8-dihydro-1,6-naphthyridin-6(5H)-yl)ethanone Hydrochloride (AMG 925 HCl)

AMG 925 HCl was isolated in 92.5% yield (7.96 kg), 99.1% overall mass balance, 83.8 wt % AMG 925, 99.75 LCAP AMG 925, 6.2 wt % Cl, 9.6 wt % water, 3800 ppm AcOH, d10 4.0 μm, d50 15.2 μm, d90 38.8 μ, Vm 18.7 μm, BET surface area 1.5 m2/g.

1H NMR (400 MHz, acetic acid-d4, mixture of two rotamers at 20 °C) 9.63 (s, 1H), 9.56 (s, 1H), 8.71–8.76 (m, 1H), 8.60–8.66 (m, 1H), 8.20–8.29 (m, 1H), 7.90–7.98 (m, 1H), 4.90–5.01 (m, 1H), 4.86 and 4.70 (2 singlets, 2H), 4.53 and 4.51 (2 singlets, 2H), 4.05 and 3.82 (2 triplets, 2H, J = 6 Hz), 3.11–3.26 (m, 2H), 2.68 (q, 2H, J = 12 Hz), 1.95–2.13 (m, 4H), 1.74 (br s, 1H), 1.36 (q, 2H, J = 12 Hz), 1.06 (d, 3H, J = 8 Hz);

13C NMR (100 MHz, acetic acid-d4, mixture of two rotamers at 20 °C) 174.9, 174.8, 161.3, 161.2, 160.5, 157.5, 151.6, 151.5, 149.3, 148.9, 145.5, 138.1, 136.0, 129.3, 129.2, 127.1, 126.6, 120.9, 116.7, 116.6, 110.8, 110.7, 63.0, 62.9, 59.3, 46.4, 45.3, 43.2, 41.3, 36.9, 34.3, 32.6, 31.3, 30.6, 24.4; exact mass [C26H29N7O2 + H]+: calculated = 472.2461, measured = 472.2451.

References:

1. K. Keegan et al, Preclinical evaluation of AMG 925, a FLT3/CDK4 dual kinase inhibitor for treating acute myeloid leukemia. Mol Cancer Ther. 2014 Apr;13(4):880-9.
2. ZH Li, et al, Discovery of AMG 925, a FLT3 and CDK4 Dual Kinase Inhibitor with Preferential Affinity for the Activated State of FLT3, J. Med Chem, March 18, 2014

OFLOXACIN


Ofloxacin.svg

OFLOXACIN

Molecular Formula: C18H20FN3O4; (Formula Weight: 361.37;

mp: 270-275°C;

Ofloxacin is one kind of white or almost powder or off-white solid.

The Systematic (IUPAC) name of this chemical is (RS)-7-fluoro-2-methyl-6-(4-methylpiperazin-1-yl)-10-oxo-4-oxa-1-azatricyclo[7.3.1.05,13]trideca-5(13),6,8,11-tetraene-11-carboxylic acid

82419-36-1

Apazix; Bactocin; Exocin; Flobacin; Floxal; Floxil; Floxin; Girasid; Monoflocet; Ocuflox; Oflocet; Oflocin; Oxaldin; Tarivid; Urosin; Visiren; Zanocin

DL-8280; HOE-280; Ofloxacinum

ofloxacin.png

OFLOXACIN was developed as a broader-spectrum analog of norfloxacin, the first fluoroquinolone antibiotic, Ofloxacin was first patented in 1982 (European Patent Daiichi) and received U.S. Food and Drug Administration (FDA) approval December 28, 1990. In the United States name branded ofloxacin is rarely used anymore, having been discontinued by the manufacturer (Ortho McNeil Janssen). Johnson and Johnson’s annual sales of Floxin in 2003 was approximately $30 million, where as their combined sales of Levaquin/Floxin exceeded $ 1.15 billion in the same year. During the 2008 Johnson & Johnson shareholder’s meetings, the safety of both ofloxacin and levafloxacin were called into question. During the 2009 meeting, yet another shareholder who alleges to have been crippled by these drugs, John Fratti, raised these same issues having seen no significant changes in the warnings (regarding the issues raised during the 2008 meeting). Once again a public request for stronger warnings for both ofloxacin and levofloxacin was made.

Ofloxacin is a synthetic antibiotic of the fluoroquinolone drug class considered to be a second-generation fluoroquinolone.[1][2]

Ofloxacin was first patented in 1982 (European Patent Daiichi) and received approval from the U.S. Food and Drug Administration (FDA) on December 28, 1990. Ofloxacin is sold under a wide variety of brand names as well as generic drug equivalents, for oral and intravenous administration. Ofloxacin is also available for topical use, as eye drops and ear drops (marketed as Ocuflox and Floxin Otic respectively in the United States and marketed as Optiflox, eylox respectively in Jordan and Saudi Arabia[3]).

Ofloxacin is a racemic mixture, which consists of 50% levofloxacin (the biologically active component) and 50% of its “mirror image” or enantiomer dextrofloxacin.[4]

Ofloxacin has been associated with adverse drug reactions, such as tendon damage (including spontaneous tendon ruptures) and peripheral neuropathy (which may be irreversible); tendon damange may manifest long after therapy had been completed, and, in severe cases, may result in lifelong disabilities.[5]

History

Ofloxacin was developed as a broader-spectrum analog of norfloxacin, the first fluoroquinolone antibiotic,[6] Ofloxacin was first patented in 1982 (European Patent Daiichi) and received U.S. Food and Drug Administration (FDA) approval December 28, 1990.

In the United States name branded ofloxacin is rarely used anymore, having been discontinued by the manufacturer, Ortho-McNeil-Janssen, a subsidiary of Johnson & Johnson.[7] Johnson and Johnson’s annual sales of Floxin in 2003 was approximately $30 million, whereas their combined sales of Levaquin/Floxin exceeded $1.15 billion in the same year.[8][9] However generic use continues. The FDA website lists Floxin (Ortho McNeil Jannsen) as being discontinued, with just a few generic equivalents still in use. The otic solution continues to be listed as being available both as an original drug as well as a generic equivalent.

Medical uses

In the in the U.S. ofloxacin is approved for the treatment of bacterial infections such as:

  • Uncomplicated skin and skin structure infections
  • Acute, uncomplicated urethral and cervical gonorrhea.

Ofloxacin has not been shown to be effective in the treatment of syphilis.[10] Floxin is no longer considered a first line treatment for gonnorrhea due to bacterial resistance.[11][12][13]

Available forms

Ofloxacin for systemic use is available as tablet (multiple strengths), oral solution (250 mg/mL), and injectable solution (multiple strengths). It is also used as eye drops and ear drops. It is also available in combination with ornidazole.

Mode of action

Ofloxacin is a broad-spectrum antibiotic that is active against both Gram-positive and Gram-negative bacteria. It functions by inhibiting DNA gyrase, a type II topoisomerase, and topoisomerase IV,[14] which is an enzyme necessary to separate (mostly in prokaryotes, in bacteria in particular) replicated DNA, thereby inhibiting bacterial cell division.

…………………………..

EP0047005

US4382892 Doi: 10.1248/cpb.34.4098

Doi: 10.1248/cpb.35.1896

………………………………

doi: 10.1248/cpb.34.4098

…………………………

http://www.google.com/patents/EP0271275A1?cl=en

Reference example

  • By using 2,4,4-trimethylcyclopentyl acid as a start­ing material, ethyl 9,l0-difluoro-3-methyl-7-oxo-2,3-di­hydro-7H-pyrido[l,2,3-de] [l,4]benzoxazine-6-carboxylate (IV) which is an important intermediate for synthesis of an antibacterial agent, ofloxacin (9-fluoro-3-methyl-l0-­(4-methyl-l-piperazinyl)-7-oxo-2,3-dihydro-7H-pyrido[l,2,­3-de][l,4]benzoxazine-6-carboxylic acid) was synthesized following the reaction schemes shown below.

[Step 1]

  • To l2.6 g (0.066 mole) of 2,4,4-trimethylcyclopentyl acid was added 40 ml of acetic anhydride, and the mixture was stirred for l5 hours under reflux. The reaction mixture was poured into ice-cold water, and then extracted with chloroform. The chloroform layer was washed with water, condensed under reduced pressure and the residue was washed with n-hexane to give 6.l0 g of 3-acetoxy-2,4,5-­trifluorobenzoic acid (V) as colorless powder.Mass (CI): m/e 235 (M⁺ + l), 2l7 (M⁺ – OH), l75 (M⁺ – CH₃COO)

[Steps 2, 3, 4, 5 and 6]

  • In 200 ml of benzene was dissolved 6.l0 g (0.026 mole) of 3-acetoxy-2,4,5-trifluorobenzoic acid (V), and to the solution was added l5 ml of thionyl chloride and stirred for 4 hours under reflux. After completion of the reac­tion, benzene and excess thionyl chloride were completely distilled off under reduced pressure to give 3-acetoxy-­2,4,5-trifluorobenzoyl chloride (VI).
  • On the other hand, to l00 ml of anhydrous diethyl ether were added 3.l7 g (0.028 mole) of magnesium ethoxide and 4.30 g (0.027 mole) of diethyl malonate and refluxed for 3 hours to give a suspension of ethoxymagnesium malonic diethyl ester in diethylether. To the suspension was added dropwise a solution of the above acid chloride dissolved in 50 ml of anhyrous diethyl ether, and after completion of the dropwise addition, the mixture was further stirred for an hour at room temperature. After completion of the reaction, l N hydrochloric acid was added to the mixture to made it acidic, and the mixture was extracted with ethyl acetate. The organic layer was washed with water and dried, and then the solvent was distilled under reduced pressure to give l0.39 g of di­ethyl 3-acetoxy-2,4,5-trifluorobenzoylmalonate (VII) as yellowish oily product.
  • Then, the yellowish oily product was dissolved in l20 ml of dioxane and 4.90 g (0.026 mole) of p-toluenesulfonic acid monohydrate was added to the mixture and refluxed for l5 hours. After completion of the reaction, dioxane was distilled under reduced pressure. To the residue were added l00 ml of water and 2.l5 g (0.026 mole) of sodium hydrogen carbonate and the mixture was extracted with chloroform. The chloroform layer was washed with water, dried and then distilled under reduced pressure to give 7.64 g of ethyl 3-acetoxy-2,4,5-trifluorobenzoylacetate (VIII) as reddish oily product.
  • To 7.64 g (0.025 mole) of the ethyl 3-acetoxy-2,4,5-tri­fluorobenzoylacetate (VIII) thus obtained were added 20 ml of acetic anhydride and 6 ml of ortho-ethyl formate and the mixture was refluxed for 2 hours and then condensed under reduced pressure. The residue was dissolved in 50 ml of dichloromethane, added l.9l g (0.026 mole) of DL-2-­aminopropanol and allowed to stand over night. Dichloro­methane was distilled under reduced pressure and the residue was applied to silica gel column chromatography (solvent: mixture of toluene : ethyl acetate = l : l) to give 4.37 g of ethyl-2-(3-acetoxy-2,4,5-trifluorobenzoyl)-­3-(2-hydroxy-l-methylethyl)aminoacrylate (X) as pale yellow oily product.Mass: m/e 389 (M⁺), 358 (M⁺ – CH₂OH), 43 (+

    CH₃)

[Step 7]

  • In 30 ml of dimethylformamide was dissolved 4.30 g of the ethyl-2-(3-acetoxy-2,4,5-trifluorobenzoyl)-3-(2-hydroxy-l-­methylethyl)aminoacrylate (X) thus obtained and l.92 g (0.033 mole) of potassium fluoride was added to the mix­ture and the mixture was stirred at l40 to l50 °C for 2 hours. After completion of the reaction, the solvent was distilled under reduced pressure. To the residue was added water and the mixture was extracted with dichloro­methane, and the organic layer was washed with water, dried and then condensed under reduced pressure. Then, the residue was washed with ethanol, and the residue was recrystallized from acetone to give l.40 g of ethyl-9,l0-­difluoro-3-methyl-7-oxo-2,3-dihydro-7H-pyrido[l,2,3-de]­[l,4]benzoxazine-6-carboxylate (IV) as pale brown fine needle crystals.M.p.: 255 to 256 °C
    Elemental analysis (%): as C₁₅H₁₃F₂NO₄

  • According to the present invention, a novel compound 2,4,4-trimethylcyclopentyl acid useful as the syn­thetic intermediate for quinolone carboxylic acid deriva­tives which is useful as antibacterial agents can be provided, and the preparation steps of said quinolone carboxylic acid derivatives can be shortened to a great extent by use of said compound.

ofloxacin.png

1H NMR PREDICT

logo

Ofloxacin NMR spectra analysis, Chemical CAS NO. 82419-36-1 NMR spectral analysis, Ofloxacin H-NMR spectrum

13 C NMR PREDICT

logo

Ofloxacin NMR spectra analysis, Chemical CAS NO. 82419-36-1 NMR spectral analysis, Ofloxacin C-NMR spectrum

 OFLOXACIN COSY NMR
Ofloxacin COSY
OFLOXACIN 13 C
Ofloxacin NMR 13
OFLOXACIN
Ofloxacin NMR
OFLOXACIN 1H NMR
Ofloxacin.pdf 1H NMR
 OFLOXACIN HSQC NMR
OFLOX HSQC
 OFLOXACIN MASS SPECTRUM
OFLOX MASS
 OFLOXACIN 13 C NMR
OFLOX13C
Production of Ofloxacin
The partial hydrolysis ot 2,3,4-trifluoronitrobenzene (I) with KOH in DMSO gives 2,3-difluoro-6-nitrophenol (II), which by condensation with chloroacetone (III) by means of K2CO3 – KI in refluxing acetone yields 2-acetonyloxy-3,4-difluoronitrobenzene (IV). The reductive cyclization of (IV) with H2 over Raney-Ni in ethanol affords 7,8-difluoro-2,3-dihydro-3-methyl-4H-benzoxazine (V), which is condensed with diethyl ethoxymethylenemalonate (VI) by heating at 145 C giving the malonic derivative (VII). The cyclization of (VII) by heating at 145 C with ethyl polyphosphate (PPE) yields ethyl 9,10-difluoro-3-methyl-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylate (VIII), which is hydrolyzed with HCl in refluxing acetic acid affording the corresponding free acid (IX). Finally, this compound is condensed with N-methylpiperazine (X) in DMSO at 110 C.

(1) 2,3,4-trifluoronitrobenzene as the starting material by selective alkaline hydrolysis, etherification, restore, and C2H5OCH=C(COOEt)2 or (CH3)2NCH=C (COOEt)2 condensation ringaggregate, after hydrolysis with acetic acid boron role, and then the introduction of N-methyl-piperazine-derived products.Production of Ofloxacin

(2) Phthalimide derivative as a raw material generated by fluorination tetrafluorophthalic phthalimide, hydrolysis, decarboxylation of 2,3,4,5-tetrafluoro-benzoic acid, and then chlorinated, acylatingdecarboxylated 2,3,4,5-tetrafluorobenzoyl ethyl acetate, and then the first and of triethyl orthoformate, and after 2-aminopropanol reaction, and then cyclization generated pyridine [1,2,3-de] [1,4] benzo Hey triazine derivatives, and finally reaction of ofloxacin and piperazine.

Production of Ofloxacin

……………….

Studies on NMR Behavior of Ofloxacin in Different pH Environment
QI Jian1, GAO Xiu-Xiang1, ZHAO Mei-Xian2, XIANG Jun-Feng3, LIN Chong-Xi1*, XU Yi-Zhuang1*, WU Jin-Guang1
  1. College of Chemical and Molecular Engineering, Peking University, Beijing 100871, China;
  2. Applied Chemistry Department, School of Science, Beijing University of Chemical Technology, Beijing 100029, China;
  3. Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China

http://www.cjcu.jlu.edu.cn/EN/Y2007/V28/I5/913#

Download: PDF (403 KB)

Systematic NMR spectroscopic investigation on ofloxacin in both acidic and alkaline solutions was carried out via 1H, 13C NMR, DEPT, COSY, HSQC spectra together with HMBC techniques. Complete assignment on 1H and 13C NMR of ofloxacin was obtained in different pH environments where the coupling constant between 13C and 19F was found to be very helpful for the assignment of aromatic 13C NMR signals. Additionally, the chemical shifts of 1H from the complex spin systems such as AA’BB’ were obtained using HSQC technique. Comparisons were made among the NMR spectra in acidic solution and those in alkaline solution, which demonstrate that: (1) deprivation of H+ from COOH in alkaline solution destroys the hydrogen bond between COOH and carbonyl group in ofloxacin. This brings about the redistribution of π elelctrons around the carboxyl and carbonyl groups so that significant variations of 13C NMR chemical shift and coupling constant JFC are observed. (2) In the alkaline solution, the removal of proton from N4 in piperazine ring induces considerable variation of chemical shift of methylene groups and causes remarkable changes of dynamic behavior of the piperazine ring.

QI Jian, GAO Xiu-Xiang1, ZHAO Mei-Xian2 et al. Studies on NMR Behavior of Ofloxacin in Different pH Environment[J]. Chemical Journal of Chinese Universities, 2007, 28(5): 913-917.
URL:
http://www.cjcu.jlu.edu.cn/EN/      OR     http://www.cjcu.jlu.edu.cn/EN/Y2007/V28/I5/913

OFLOX ASSIG

OFLOX CHINESE

References

External links

Package insert links
Ofloxacin
Title: Ofloxacin
CAS Registry Number: 82419-36-1
CAS Name: 9-Fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylic acid
Additional Names: ofloxacine
Manufacturers’ Codes: DL-8280; HOE-280
Trademarks: Exocin (Allergan); Flobacin (Sigma-Tau); Floxil (Janssen-Cilag); Floxin (Ortho-McNeil); Monoflocet (Aventis); Ocuflox (Allergan); Oflocet (Aventis); Oflocin (GSK); Tarivid (Aventis)
Molecular Formula: C18H20FN3O4
Molecular Weight: 361.37
Percent Composition: C 59.83%, H 5.58%, F 5.26%, N 11.63%, O 17.71%
Literature References: Broad spectrum, fluorinated quinolone antibacterial. Prepn: I. Hayakawa et al., EP 47005; eidem, US4382892 (1982, 1983 both to Daiichi). Total synthesis: H. Egawa et al., Chem. Pharm. Bull. 34, 4098 (1986). Synthesis and activity of optical isomers: S. Atarashi et al., ibid. 35, 1896 (1987). Antibacterial spectrum of racemate: K. Sato et al., Antimicrob. Agents Chemother. 22, 548 (1982). Mechanism of differential activity of enantiomers: I. Morrissey et al., ibid. 40, 1775 (1996). Toxicity data: H. Ohno et al., Chemotherapy (Tokyo) 32, Suppl. 1, 1084 (1984). Pharmacology and clinical efficacy: Infection 14,Suppl. 1, S1-S109 (1986). Symposium on pharmacokinetics and therapeutic use: Scand. J. Infect. Dis. Suppl. 68, 1-69 (1990). Review of antibacterial spectrum, pharmacology, and clinical efficacy: J. P. Monk, D. M. Campoli-Richards, Drugs 33, 346-391 (1987); of mechanism of action: K. Drlica, Curr. Opin. Microbiol. 2, 504-508 (1999).
Properties: Colorless needles from ethanol, mp 250-257° (dec). LD50 in male, female mice, male, female rats (mg/kg): 5450, 5290, 3590, 3750 orally; 208, 233, 273, 276 i.v.; >10000, >10000, 7070, 9000 s.c. (Ohno).
Melting point: mp 250-257° (dec)
Toxicity data: LD50 in male, female mice, male, female rats (mg/kg): 5450, 5290, 3590, 3750 orally; 208, 233, 273, 276 i.v.; >10000, >10000, 7070, 9000 s.c. (Ohno)
 .
.
.
.
Derivative Type: S-(-)-Form
CAS Registry Number: 100986-85-4; 138199-71-0 (hemihydrate)
Additional Names: Levofloxacin
Manufacturers’ Codes: DR-3355
Trademarks: Cravit (Daiichi); Levaquin (Ortho-McNeil); Tavanic (Aventis); Quixin (Santen)
Literature References: Toxicity study: M. Kato et al., Arzneim.-Forsch. 42, 365 (1992). Series of articles on pharmacology and toxicology: ibid., 368-418. Clinical study in bacterial conjunctivitis: D. G. Hwang et al., Br. J. Ophthalmol. 87, 1004 (2003).Review: D. S. North et al., Pharmacotherapy 18, 915-935 (1998).
Properties: Prepd as the hemihydrate; needles from ethanol + ethyl ether, mp 225-227° (dec). [a]D23 -76.9° (c = 0.385 in 0.5NNaOH). Freely sol in glacial acetic acid, chloroform; sparingly sol in water. LD50 in male, female mice, male, female rats (mg/kg): 1881, 1803, 1478, 1507 orally (Kato).
Melting point: mp 225-227° (dec)
Optical Rotation: [a]D23 -76.9° (c = 0.385 in 0.5N NaOH)
Toxicity data: Freely sol in glacial acetic acid, chloroform; sparingly sol in water. LD50 in male, female mice, male, female rats (mg/kg): 1881, 1803, 1478, 1507 orally (Kato)
Therap-Cat: Antibacterial.
Keywords: Antibacterial (Synthetic); Quinolones and Analogs.
Ofloxacin
Ofloxacin.svg
Ofloxacin ball-and-stick.png
Systematic (IUPAC) name
(RS)-7-fluoro-2-methyl-6-(4-methylpiperazin-1-yl)-10-oxo-4-oxa-1-azatricyclo[7.3.1.05,13]trideca-5(13),6,8,11-tetraene-11-carboxylic acid
Clinical data
Trade names Floxin, Ocuflox
AHFS/Drugs.com monograph
MedlinePlus a691005
Legal status
Routes Oral, IV, topical (eye drops and ear drops)
Pharmacokinetic data
Bioavailability 85% – 95%
Protein binding 32%
Half-life 8–9 hours
Identifiers
CAS number 82419-36-1 Yes
ATC code J01MA01 ,S01AE01, S02AA16
PubChem CID 4583
DrugBank DB01165
ChemSpider 4422 Yes
UNII A4P49JAZ9H Yes
KEGG D00453 Yes
ChEBI CHEBI:7731 Yes
ChEMBL CHEMBL4 Yes
Synonyms (±)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylic acid
Chemical data
Formula C18H20FN3O4 
Molecular mass 361.368 g/mol

New information about CEPs and inspections published by EDQM….see about Telangana, India


DR ANTHONY MELVIN CRASTO Ph.D's avatarDRUG REGULATORY AFFAIRS INTERNATIONAL

The European Directorate for the Quality of Medicines & Healthcare (EDQM) has published new information about the CEP procedure and its related inspections. Please read more about he latest updates from EDQM.

http://www.gmp-compliance.org/enews_4746_New-information-about-CEPs-and-inspections-published-by-EDQM_9196,S-WKS_n.html

The European Directorate for the Quality of Medicines & Healthcare (EDQM) has published new information about the CEP procedure and its related inspections.

1) Costs of inspections

The EDQM has published a new document which describes the inspection costs. The EDQM document PA/PH/CEP (12) 28 1R refers to a table of fees and inspection costs. The costs for the inspection as well as for the travel will be invoiced prior to the inspection. For a three day inspection, for example, the fee is 5000,- Euro. If the facility is located in Asia a flat rate of 6000,- Euro will be charged to cover the travel costs, food and accommodation for the inspector. The travel costs are less…

View original post 118 more words

CILNIDIPINE 西尼地平


 

 

Cilnidipine

西尼地平

CAS 132203-70-4

  • (E) – (±) 1 ,4 a dihydro-2 ,6 – dimethyl-4 – (3 – nitrophenyl) -3,5 – pyridinedicarboxylic acid, 2 – methoxy- ethyl butylester 3 – phenyl – 2 – propenyl ester FRC-8653 Cinalong
  • More FRC 8653 1,4-Dihydro-2 ,6-dimethyl-4-(3-nitrophenyl) 3 ,5-pyridinedicarboxylic acid 2-methoxyethyl (2E)-3-phenyl-2-propenyl ester
  • Molecular formula:27 H 28 N 2 O 7
  • Molecular Weight:492.52
CAS Name: 1,4-Dihydro-2,6-dimethyl-4-(3-nitrophenyl)-3,5-pyridinedicarboxylic acid 2-methoxyethyl (2E)-3-phenyl-2-propenyl ester
Additional Names: (±)-(E)-cinnamyl 2-methoxyethyl 1,4-dihydro-2,6-dimethyl-4-(m-nitrophenyl)-3,5-pyridinedicarboxylate
Cinnamyl 2-methoxyethyl 4-(3-nitrophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate
Manufacturers’ Codes: FRC-8653
Trademarks: Atelec (Morishita); Cinalong (Fujirebio); Siscard (Boehringer, Ing.)
Percent Composition: C 65.84%, H 5.73%, N 5.69%, O 22.74%
Properties: Crystals from methanol, mp 115.5-116.6°. LD50 in male, female mice, rats (mg/kg): ³5000, ³5000, ³5000, 4412 orally;³5000 all species s.c.; 1845, 2353, 441, 426 i.p. (Wada).
Melting point: mp 115.5-116.6°
Toxicity data: LD50 in male, female mice, rats (mg/kg): ³5000, ³5000, ³5000, 4412 orally; ³5000 all species s.c.; 1845, 2353, 441, 426 i.p. (Wada)
Ajinomoto (INNOVATOR)
 Antihypertensive; Dihydropyridine Derivatives; Calcium Channel Blocker; Dihydropyridine Derivatives.

 

Cilnidipine (INN) is a calcium channel blocker. It is sold as Atelec in Japan, asCilaheart, Cilacar in India, and under various other trade names in East Asian countries.

Cilnidipine is a dual blocker of L-type voltage-gated calcium channels in vascular smooth muscle and N-type calcium channels in sympathetic nerve terminals that supply blood vessels. However, the clinical benefits of cilnidipine and underlying mechanisms are incompletely understood.

Clinidipine is the novel calcium antagonist accompanied with L-type and N-type calcium channel blocking function. It was jointly developed by Fuji Viscera Pharmaceutical Company, Japan and Ajinomoto, Japan and approved to come into market for the first time and used for high blood pressure treatment in 1995. in india j b chemicals & pharmaceuticals ltd and ncube pharmaceutical develope a market of cilnidipine.

Hypertension is one of the most common cardiovascular disease states, which is defined as a blood pressure greater than or equal to 140/90 mm Hg. Recently, patients with adult disease such as hypertension have rapidly increased. Particularly, since damages due to hypertension may cause acute heart disease or myocardial infarction, etc., there is continued demand for the development of more effective antihypertensive agent.

Meanwhile, antihypertensive agents developed so far can be classified into Angiotensin II Receptor Blocker (ARB), Angiotensin-Converting Enzyme Inhibitor (ACEI) or Calcium Chanel Blocker (CCB) according to the mechanism of actions. Particularly, ARB or CCB drugs manifest more excellent blood pressure lowering effect, and thus they are more frequently used.

However, these drugs have a limit in blood pressure lowering effects, and if each of these drugs is administered in an amount greater than or equal to a specific amount, various side-effects may be caused. Therefore, there have been many attempts in recent years to obtain more excellent blood pressure lowering effect by combination therapy or combined preparation which combines or mixes two or more drugs.

Particularly, since side-effect due to each drug is directly related to the amount or dose of a single drug, there have been active attempts to combine or mix two or more drugs thereby obtaining more excellent blood pressure lowering effect through synergism of the two or more drugs while reducing the amount or dose of each single drug.

For example, US 20040198789 discloses a pharmaceutical composition for lowering blood pressure combining lercanidipine, one of CCB, and valsartan, irbesartan or olmesartan, one of ARB, etc. In addition, a combined preparation composition which combines or mixes various blood pressure lowering drugs or combination therapy thereof has been disclosed.

cilnidipine Compared with other calcium antagonists, clinidipine can act on the N-type calcium-channel that existing sympathetic nerve end besides acting on L-type calcium-channel that similar to most of the calcium antagonists. Due to its N-type calcium-channel blocking properties, it has more advantages compared to conventional calcium-channel blockers. It has lower incidence of Pedal edema, one of the major adverse effects of other calcium channel blockers. Cilnidipine has similar blood pressure lowering efficacy as compared to amlodipine. One of the distinct property of cilnidipine from amlodipine is that it does not cause reflex tachycardia.

In recent years, cardiovascular disease has become common, the incidence increased year by year, about a patient of hypertension in China. 3-1. 500 million, complications caused by hypertension gradually increased, and more and more young patients with hypertension technology. In recent years, antihypertensive drugs also have great development, the main first-line diuretic drug decompression 3 – blockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, ar blockers and vascular angiotensin II (Ang II) receptor antagonist.

In the anti-hypertensive drugs, calcium antagonists are following a – blockers after another rapidly developing cardiovascular drugs, has been widely used in clinical hypertension, angina and other diseases, in cardiovascular drugs in the world, ranked first.

Cilnidipine for the long duration of the calcium channel blockers, direct relaxation of vascular smooth muscle, dilation of peripheral arteries, the peripheral resistance decreased, with lower blood pressure, heart rate without causing a reflex effect.

Cilnidipine is a dihydropyridine CCB as well as an antihypertensive. Cilnidipinehas L- and N-calcium channel blocking actions. Though many of the dihydropyridine CCBs may cause an increase in heart rate while being effective for lowering blood pressure, it has been confirmed that cilnidipine does not increase the heart rate and has a stable hypotensive effect. (Takahiro Shiokoshi, “Medical Consultation & New Remedies” vol. 41, No. 6, p. 475-481)

  • http://www.mcyy.com.cn/e-product2.asp
  • Löhn M, Muzzulini U, Essin K, et al. (May 2002). “Cilnidipine is a novel slow-acting blocker of vascular L-type calcium channels that does not target protein kinase C”. J. Hypertens.20 (5): 885–93. PMID12011649.

read more on dipine series………http://organicsynthesisinternational.blogspot.in/p/dipine-series.html

Cilnidipine (CAS NO.: 132203-70-4), with its systematic name of (+-)-(E)-Cinnamyl 2-methoxyethyl 1,4-dihydro-2,6-dimethyl-4-(m-nitrophenyl)-3,5-pyridinedicarboxylate, could be produced through many synthetic methods.

Following is one of the synthesis routes: By cyclization of 2-(3-nitrobenzylidene)acetocetic acid cinnamyl ester (I) with 2-aminocrotonic acid 2-methoxyethyl ester (II) by heating at 120 °C.

………………..

http://www.google.com/patents/EP0161877A2?cl=en

AN EXAMPLE

Example 1

  • 3.51 g (10 mM) of 2-(3-nitrobenzylidene) acetoacetic acid cinnamyl ester were mixed with 1.38 g (12 mM) of 3-aminocrotonic acid methyl ester, and heated at 120°C for 3 hours. The reaction mixture was separated by silica gel column chromatography, and 3.00 g of cinnamyl methyl 4-(3-nitrophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate (trans) were obtained (yield 67%). This derivative was recrystallized once from methanol.
  • Elemental Analysis; C25H24N206

    • Calcd. (%) C: 66.95, H: 5.39, N: 6.25
    • Found (%) C: 67.03, H: 5.31, N: 6.20

(trans)

    • m.p.; 143.5-144.5°C
    • IR (cm-1); vNH 3370, νCO 1700, νNO2 1530, 1350
    • NMR δCDCl3; 2.34(s,6H), 3.60(s,3H), 4.69(d,2H), 5.13(s,lH), 6.14(tt,lH), 6.55(d,lH), 7.1-8.1(m,9H)

(cis)

    • m.p.; 136-137°C
    • IR (cm-1); vNH 3360, νCO 1700, 1650, νNO2 1530, 1350
    • NMR δCDCl3; 2.30(s,6H), 3,60(s,3H), 4.80(d,lH), 5.10(s,1H), 5.77(tt,lH), 6.56(d,1H), 6.64(bs,1H), 7.1-8.1(m,9H)

     

 EXAMPLE 13

 

  • Example 13 Cinnamyl 2-methoxyethyl 4-(3-nitrophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate
  • Elemental Analysis; C27H28N2O7

    • Calcd. (%) C: 65.84, H: 5.73, N: 5.69
    • Found (%) C: 65.88, H: 5.70, N: 5.66
    • m.p.; 115.5-116.5°C
    • IR (cm-1); vNH 3380, νCO 1710, 1680, νNO2 1530, 1350
    • NMR δCDCl3; 2.34(s,6H), 3.25(s,3H), 3.50(t,2H), 4.15(t,2H), 4.68(d,2H), 5.15(s,lH), 5.9-6.9(m,3H), 7.1-8.2(m,9H)

 

<br /><br /><br /> Cilnidipine<br /><br /><br /> pk_prod_list.xml_prod_list_card_pr?p_tsearch=A&p_id=131335<br /><br /><br />

cyclization of 2-(3-nitrobenzylidene)acetocetic acid cinnamyl ester (I) with 2-aminocrotonic acid 2-methoxyethyl ester (II) by heating at 120 C.

read more on dipine series………http://organicsynthesisinternational.blogspot.in/p/dipine-series.html

MORE

 

NMR

CARBOHYDRATE POLYMERS 90 PG 1719-1724 , YR2012

Numerous peaks were found in the spectrum of cilnidipine: 2.3555 (3H, s, CH3), 2.3886(3H, s, CH3), 3.2843(CD3OD), 3.3292(3H, s, OCH3), 3.5255–3.5623(2H, m, CH3OCH2CH2 ), 4.1224–4.1597(2H, m, CH3OCH2CH2 ), 4.6695–4.7293(2H, m, CH2 CH CH ), 4.8844(D2O), 5.1576(1H, s, CH), 6.2609(1H, dt, CH2 CH CH ), 6.5518(1H, d, CH2 CH CH ), 7.2488–7.3657(6H, m, ArH), 7.7002(1H, dd, ArH), 7.9805(1H, dd, ArH), 8.1548(1H, s, ArH)

CILNIDIPINE FT IR

 

CILNIDIPINE NMR

 

References: 

Dihydropyridine calcium channel blocker. Prepn: T. Kutsuma et al., EP 161877; eidem, US 4672068(1985, 1987 both to Fujirebio).

Pharmacology: K. Ikeda et al., Oyo Yakuri 44, 433 (1992).

 

Mechanism of action study: M. Hosonoet al., J. Pharmacobio-Dyn. 15, 547 (1992).

LC-MS determn in plasma: K. Hatada et al., J. Chromatogr. 583, 116 (1992). Clinical study: M. Ishii, Jpn. Pharmacol. Ther. 21, 59 (1993).

Acute toxicity study: S. Wada et al., Yakuri to Chiryo 20, Suppl. 7, S1683 (1992), C.A. 118, 32711 (1992).

read more on dipine series………http://organicsynthesisinternational.blogspot.in/p/dipine-series.html

U.S Patent No. 4,572,909 discloses amlodipine;

U.S Patent No. 4,446,325 discloses aranidipine;

U.S Patent No. 4,772,596 discloses azelnidipine;

U.S Patent No. 4,220,649 discloses barnidipine;

U.S Patent No. 4,448,964 discloses benidipine;

U.S Patent No. 5,856,346 discloses clevidipine;

U.S Patent No. 4,466,972 discloses isradipine;

U.S Patent No. 4,885,284 discloses efonidipine; and

U.S Patent No. 4,264,61 1 discloses felodipine.
read more on dipine series………http://organicsynthesisinternational.blogspot.in/p/dipine-series.html

  • Planar chemical structures of these calcium blockers of formula (I) are shown below.

    Figure 00070001
    Figure 00070002
    Figure 00070003
    Figure 00070004
    Figure 00070005
    Figure 00080001
    Figure 00080002
    Figure 00080003
    Figure 00080004
  • Amlodipine is 2-(2-aminoethoxymethyl)-4-(2-chlorophenyl)-3-ethoxycarbonyl-5-methoxycarbonyl-6-methyl-1,4-dihydropyridine disclosed in USP 4,572,909, Japanese patent publication No. Sho 58-167569 and the like.
  • Aranidipine is 3-(2-oxopropoxycarbonyl)-2,6-dimethyl-5-methoxycarbonyl-4-(2-nitrophenyl)-1,4-dihydropyridine disclosed in USP 4,446,325 and the like.
  • Azelnidipine is 2-amino-3-(1-diphenylmethyl-3-azetidinyloxycarbonyl)-5-isopropoxycarbonyl-6-methyl-4-(3-nitrophenyl)-1,4-dihydropyridine disclosed in USP 4,772,596, Japanese patent publication No. Sho 63-253082 and the like.
  • Barnidipine is 3-(1-benzyl-3-pyrrolidinyloxycarbonyl)-2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine disclosed in USP 4,220,649, Japanese patent publication No. Sho 55-301 and the like.
  • Benidipine is 3-(1-benzyl-3-piperidinyloxycarbonyl)-2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine and is described in the specifications of U.S. Patent No. 4,501,748, Japanese patent publication No. Sho 59-70667 and the like.
  • Cilnidipine is 2,6-dimethyl-5-(2-methoxyethoxycarbonyl)-4-(3-nitrophenyl)-3-(3-phenyl-2-propenyloxycarbonyl)-1,4-dihydropyridine disclosed in USP 4,672,068, Japanese patent publication No. Sho 60-233058 and the like.
  • Efonidipine is 3-[2-(N-benzyl-N-phenylamino)ethoxycarbonyl]-2,6-dimethyl-5-(5,5-dimethyl-1,3,2-dioxa-2-phosphonyl)-4-(3-nitrophenyl)-1,4-dihydropyridine disclosed in USP 4,885,284, Japanese patent publication No. Sho 60-69089 and the like.
  • Elgodipine is 2,6-dimethyl-5-isopropoxycarbonyl-4-(2,3-methylenedioxyphenyl)-3-[2-[N-methyl-N-(4-fluorophenylmethyl)amino]ethoxycarbonyl]-1,4-dihydropyridine disclosed in USP 4,952,592, Japanese patent publication No. Hei 1-294675 and the like.
  • Felodipine is 3-ethoxycarbonyl-4-(2,3-dichlorophenyl)-2,6-dimethyl-5-methoxycarbonyl-1,4-dihydropyridine disclosed in USP 4,264,611, Japanese patent publication No. Sho 55-9083 and the like.
  • Falnidipine is 2,6-dimethyl-5-methoxycarbonyl-4-(2-nitrophenyl)-3-(2-tetrahydrofurylmethoxycarbonyl)-1,4-dihydropyridine disclosed in USP 4,656,181, Japanese patent publication (kohyo) No. Sho 60-500255 and the like.
  • Lemildipine is 2-carbamoyloxymethyl-4-(2,3-dichlorophenyl)-3-isopropoxycarbonyl-5-methoxycarbonyl-6-methyl-1,4-dihydropyridine disclosed in Japanese patent publication No. Sho 59-152373 and the like.
  • Manidipine is 2,6-dimethyl-3-[2-(4-diphenylmethyl-1-piperazinyl)ethoxycarbonyl]-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine disclosed in USP 4,892,875, Japanese patent publication No. Sho 58-201765 and the like.
  • Nicardipine is 2,6-dimethyl-3-[2-(N-benzyl-N-methylamino)ethoxycarbonyl]-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine disclosed in USP 3,985,758, Japanese patent publication No. Sho 49-108082 and the like.
  • Nifedipine is 2,6-dimethyl-3,5-dimethoxycarbonyl-4-(2-nitrophenyl)-1,4-dihydropyridine disclosed in USP 3,485,847 and the like.
  • Nilvadipine is 2-cyano-5-isopropoxycarbonyl-3-methoxycarbonyl-6-methyl-4-(3-nitrophenyl)-1,4-dihydropyridine disclosed in USP 4,338,322, Japanese patent publication No. Sho 52-5777 and the like.
  • Nisoldipine is 2,6-dimethyl-3-isobutoxycarbonyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine disclosed in USP 4,154,839, Japanese patent publication No. Sho 52-59161 and the like.
  • Nitrendipine is 3-ethoxycarbonyl-2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine disclosed in USP 3,799,934, Japanese patent publication (after examination) No. Sho 55-27054 and the like.
  • Pranidipine is 2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-3-(3-phenyl-2-propen-1 -yloxycarbonyl)-1,4-dihydropyridine disclosed in USP 5,034,395, Japanese patent publication No. Sho 60-120861 and the like.

read more on dipine series………http://organicsynthesisinternational.blogspot.in/p/dipine-series.html

 

MAHABALIPURAM, INDIA

Mahabalipuram – Wikipedia, the free encyclopedia

en.wikipedia.org/wiki/Mahabalipuram

Mahabalipuram, also known as Mamallapuram is a town in Kancheepuram district in the Indian state of Tamil Nadu. It is around 60 km south from the city of …Shore Temple – ‎Seven Pagodas – ‎Pancha Rathas – ‎

Map of mahabalipuram.

.

Krishna’s Butter Ball in Mahabalipuram, India. The surface below the rock is …


http://www.weather-forecast.com/locations/Mamallapuram


Come to Mahabalipuram (also known as Mammallapuram), an enchanting beach that is located on the east coast of India.
Moonraikers Restaurant, Mamallapuram
 

Hotel Mamalla Bhavan – Mahabalipuram Chennai – Food, drink and entertainment

.

A carving at the Varaha Temple, Mahabalipuram

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

FDA publishes List of Guidances planned for 2015


DR ANTHONY MELVIN CRASTO Ph.D's avatarDRUG REGULATORY AFFAIRS INTERNATIONAL

At the beginning of each year the FDA always publishes a list of the guidances it plans to publish during that year. It has done so again in 2015. The document is relatively comprehensive, containing five pages. Find out more about the Guidances the FDA plans on publishing in 2015.

http://www.gmp-compliance.org/enews_4660_FDA-publishes-List-of-Guidances-planned-for-2015_9293,9266,Z-QAMPP_n.html

At the beginning of each year the FDA always publishes a list of the guidances it plans to publish during that year. It has done so again in 2015. The document is relatively comprehensive, containing five pages. The list is subdivided into different categories. It contains for example also guidances planned in connection with the topics Clinical Pharmacology or Clinical/Statistical.

CGMP is a category of its own for which “only” three new guidances are planned for 2015:

  • A questions & answers (Q&A) paper on the topic data integrity
  • CGMP rules for outsourced facilities (pharmacy compounding)
  • Rules for the…

View original post 190 more words

GIVINOSTAT


Givinostat structure.svg

 

GIVINOSTAT, ITF2357, UNII-5P60F84FBH, ITF-2357, Gavinostat,
[6-(diethylaminomethyl)naphthalen-2-yl]methyl N-[4-(hydroxycarbamoyl)phenyl]carbamate,
diethyl-[6-(4-hydroxycarbamoyl-phenylcarbamoyloxymethyl)-naphthalen-2-yl-methyl]-amine
4-[6-(diethylaminomethyl)naphth-2-ylmethyloxycarbamoyl]benzohydroxamic acid
CAS 497833-27-9 FREE BASE
199657-29-9 HCL SALT
Molecular Formula: C24H27N3O4
Molecular Weight: 421.48888 g/mol
PHASE 2  Italfarmaco (INNOVATOR)
DESCRIBED IN U.S. Pat. No. 6,034,096 or in U.S. Pat. No. 7,329,689.

Givinostat.pngGIVINOSTAT

 

Givinostat (INN[1]) or gavinostat (originally ITF2357) is a histone deacetylase inhibitor with potential anti-inflammatory, anti-angiogenic, and antineoplastic activities.[2] It is a hydroxamate used in the form of its hydrochloride.

Givinostat is in numerous phase II clinical trials (including for relapsed leukemias and myelomas),[3] and has been granted orphan drug designation in the European Union for the treatment of systemic juvenile idiopathic arthritis[4] and polycythaemia vera.[5]

In 2010, orphan drug designation was assigned in the E.U. for the treatment of systemic-onset juvenile idiopathic arthritis and for the treatment of polycythemia vera. In 2013, this designation was assigned by the FDA for the treatment of Duchenne’s muscular dystrophy and for the treatment of Becker’s muscular dystrophy.

ITF2357 was discovered at Italfarmaco of Milan, Italy. It was patented in 1997 and first described in the scientific literature in 2005.[6][7]

Givinostat hydrochloride, an orally active, synthetic inhibitor of histone deacetylase, is being evaluated in several early clinical studies at Italfarmaco, including studies for the treatment of myeloproliferative diseases, polycythemia vera, Duchenne’s muscular dystrophy and periodic fever syndrome. The company was also conducting clinical trials for the treatment of Crohn’s disease and chronic lymphocytic leukemia; however, the trials were terminated.

No recent development has been reported for research into the treatment of juvenile rheumatoid arthritis, for the treatment of multiple myeloma and for the treatment of Hodgkin’s lymphoma.

Muscular dystrophies (MDs) include a heterogeneous group of genetic diseases invariably leading to muscle degeneration and impaired function. Mutation of nearly 30 genes gives rise to various forms of muscular dystrophy, which differ in age of onset, severity, and muscle groups affected (Dalkilic I, Kunkel LM. (2003) Muscular dystrophies: genes to pathogenesis. Curr. Opin. Genet. Dev. 13:231-238). The most common MD is the Duchenne muscular dystrophy (DMD), a severe recessive X-linked disease which affects one in 3,500 males, characterized by rapid progression of muscle degeneration, eventually leading to loss of ambulation and death within the second decade of life.

Attempts to replace or correct the mutated gene, by means of gene or cell therapy, might result in a definitive solution for muscular dystrophy, but this is not easy to achieve. Alternative strategies that prevent or delay muscle degeneration, reduce inflammation or promote muscle metabolism or regeneration might all benefit patients and, in the. future, synergize with gene or cell therapy. Steroids that reduce inflammation are currently the only therapeutic tool used in the majority of DMD patients (Cossu G, Sampaolesi M . (2007) New therapies for Duchenne muscular dystrophy: challenges, prospects and clinical trials. TRENDS Mol . Med. 13:520-526).

Diethyl- [ 6- ( 4-hydroxycarbamoyl-phenyl-carbamoyloxy- methyl ) -naphthalen-2-yl-methyl ] -ammonium chloride , which is described in WO 97/43251 (anhydrous form) and in WO 2004/065355 (monohydrate crystal form), herein both incorporated by reference, is an anti-inflammatory agent which is able to inhibit the synthesis of the majority of pro-inflammatory cytokines whilst sparing anti-inflammatory ones. Diethyl- [ 6- ( 4-hydroxycarbamoyl-phenyl-carbamoyloxy- methyl ) -naphthalen-2-yl-methyl ] -ammonium chloride is also known as ITF2357.

The monohydrate crystal form of diethyl- [ 6- ( 4- hydroxycarbamoyl-phenyl-carbamoyloxy-methy1 ) – naphthalen-2-yl-methyl ] -ammonium chloride is known as Givinostat .

Givinostat is being evaluated in several clinical studies, including studies for the treatment of myeloproliferative diseases, polycythemia vera, periodic fever syndrome, Crohn’s disease and systemic- onset juvenile idiopathic arthritis. Orphan drug designation was assigned in the E.U. for the treatment of systemic-onset juvenile idiopathic arthritis and for the treatment of polycythemia vera.

Givinostat has been recently found to act also as a Histone Deacetylase inhibitor (WO 2011/048514).

Histone deacetylases ( HDAC ) are a family of enzymes capable of removing the acetyl group bound to the lysine residues in the N-terminal portion of histones or in other proteins.

HDACs can be subdivided into four classes, on the basis of structural homologies. Class I HDACs (HDAC 1, 2, 3 and 8) are similar to the RPD3 yeast protein and are located in the cell nucleus. Class II HDACs (HDAC 4, 5, 6, 7, 9 and 10) are similar to the HDA1 yeast protein and are located both in the nucleus and in the cytoplasm. Class III HDACs are a structurally distinct form of NAD-dependent enzymes correlated with the SIR2 yeast protein. Class IV (HDAC 11) consists at the moment of a single enzyme having particular structural characteristics. The HDACs of classes I, II and IV are zinc enzymes and can be inhibited by various classes of molecule: hydroxamic acid derivatives, cyclic tetrapeptides , short-chain fatty acids, aminobenzamides , derivatives of electrophilic ketones, and the like. Class III HDACs are not inhibited by hydroxamic acids, and their inhibitors have structural characteristics different from those of the other classes .

The expression “histone deacetylase inhibitor” in relation to the present invention is to be understood as meaning any molecule of natural, recombinant or synthetic origin capable of inhibiting the activity of at least one of the enzymes classified as histone deacetylases of class I, class II or class IV.

Although HDAC inhibitors, as a class, are considered to be potentially useful as anti-tumor agents, it is worth to note that, till now, only two of them (Vorinostat and Romidepsin) have been approved as drugs for the cure of a single tumor form (Cutaneous T-cell lymphoma ) .

It is evident that the pharmaceutical properties of each HDAC inhibitor may be different and depend on the specific profile of inhibitory potency, relative to the diverse iso-enzymes as well as on the particular pharmacokinetic behaviour and tissue distribution.

Some HDAC inhibitors have been claimed to be potentially useful, in combination with other agents, for the treatment of DMD (WO 2003/033678, WO 2004/050076, Consalvi S. et al. Histone Deacetylase Inhibitors in the Treatment of Muscular Dystrophies: Epigenetic Drugs for Genetic Diseases. (2011) Mol. Med. 17 : 457-465 ) .

The potential therapeutic use of HDAC inhibitors in DMD may however be hampered by the possible harmful effects of these relatively toxic agents, especially when used for long-term therapies in paediatric patients .

Givinostat, as anti-inflammatory agent, has been already used in a phase II study in children with Systemic Onset Juvenile Idiopathic Arthritis; Givinostat administered at 1.5 mg/kg/day for twelve weeks achieved ACR Pedi 30, 50 and 70 improvement of approximately 70% (Vojinovic J, Nemanja D. (2011) HDAC Inhibition in Rheumatoid Arthritis and Juvenile Idiopathic Arthritis. Mol. Med 17:397-403) showing only a limited number of mild or moderate but short lasting, adverse effects.

To date more than 500 patients (including 29 children) have been treated with Givinostat. Repeated dose toxicity studies were carried out in dogs, rats and monkeys. Oral daily doses of the drug were administered up to nine consecutive months. The drug was well tolerated with no overt toxicity at high doses. The “no adverse effect levels” (NOAEL) ranged from 10 to 25 mg/kg/day depending on the animal species and the duration of treatment.

In juvenile animals Givinostat at 60 mg/kg/day did not affect the behavioural and physical development and reproductive performance of pups.

No genotoxic effect was detected for Givinostat in the mouse lymphoma assay and the chromosomal aberration assay in vitro and in the micronucleus test and UDS test in vivo.

Patent Submitted Granted
Monohydrate hydrochloride of the 4-hydroxycarbamoyl-phenyl)-carbamic acid (6-diethylaminomethyl-naphtalen-2-yl) ester [US7329689] 2005-11-03 2008-02-12

Adverse effects

In clinical trials of givinostat as a salvage therapy for advanced Hodgkin’s lymphoma, the most common adverse reactions were fatigue (seen in 50% of participants), mild diarrhea or abdominal pain (40% of participants), moderate thrombocytopenia (decreased platelet counts, seen in one third of patients), and mild leukopenia (a decrease in white blood cell levels, seen in 30% of patients). One-fifth of patients experienced prolongation of the QT interval, a measure of electrical conduction in the heart, severe enough to warrant temporary suspension of treatment.[8]

Mechanism of action

Givinostat inhibits class I and class II histone deacetylases (HDACs) and several pro-inflammatory cytokines. This reduces expression of tumour necrosis factor (TNF), interleukin 1α and β, and interleukin 6.[7]

It also has activity against cells expressing JAK2(V617F), a mutated form of the janus kinase 2 (JAK2) enzyme that is implicated in the pathophysiology of many myeloproliferative diseases, including polycythaemia vera.[9][10] In patients with polycythaemia, the reduction of mutant JAK2 concentrations by givinostat is believed to slow down the abnormal growth of erythrocytes and ameliorate the symptoms of the disease.[5]

………………….

PATENT

https://www.google.com/patents/WO2004065355A1?cl=en

Hydrochloride of (6-diethylaminomethyl-naphthalen-2-yl)- methyl ester of (4-hydroxycarbamoylphenyl)-carbamic acid (II)

has been described in US patent 6,034,096 as a derivative of hydroxamic acid having anti-inflammatory and immunosuppressive activity, probably owing to the ability thereof to inhibit the production of pro-inflammatory cyto ines. This compound is obtained according to

Example 12 of the above-mentioned patent as an anhydrous, amorphous, hygroscopic, deliquescent solid which is difficult to handle.

crystalline form of monohydrous hydrochloride of

(6-diethylaminomethyl-naphthalen-2-yl)-methyl ester of

(4~hydroxycarbamoylphenyl)-carbamic acid (I).

This form is particularly advantageous from the industrial perspective because it is stable and simpler to handle than the anhydrous and amorphous form described above.

………………

PATENT

http://www.google.co.in/patents/US7329689

Hydrochloride of (6-diethylaminomethyl-naphthalen-2-yl)-methyl ester of (4-hydroxycarbamoylphenyl)-carbamic acid (II)

has been described in U.S. Pat. No. 6,034,096 as a derivative of hydroxamic acid having anti-inflammatory and immunosuppressive activity, probably owing to the ability thereof to inhibit the production of pro-inflammatory cytokines. This compound is obtained according to Example 12 of the above-mentioned patent as an anhydrous, amorphous, hygroscopic, deliquescent solid which is difficult to handle.

The 4-(6-diethylaminomethyl-naphthalen-2-ylmethoxycarbonylamino)-benzoic acid can be prepared as described in Example 12, point C, of U.S. Pat. No. 6,034,096.

The acid (1.22 kg, 3 moles) was suspended in THF (19 l) and the mixture was agitated under nitrogen over night at ambient temperature. The mixture was then cooled to 0° C. and thionyl chloride (0.657 l, 9 moles) was added slowly, still under nitrogen, with the temperature being maintained below 10° C. The reaction mixture was heated under reflux for 60 minutes, DMF (26 ml) was added and the mixture was further heated under reflux for 60 minutes.

The solvent was evaporated under vacuum, toluene was added to the residue and was then evaporated. This operation was repeated twice, then the residue was suspended in THF (11.5 l) and the mixture was cooled to 0° C.

The mixture was then poured into a cold solution of hydroxylamine (50% aq., 1.6 l, 264 moles) in 5.7 l of water. The mixture was then cooled to ambient temperature and agitated for 30 minutes. 6M HCl was added until pH 2 was reached and the mixture was partially evaporated under vacuum in order to eliminate most of the THF. The solid was filtered, washed repeatedly with water and dissolved in a solution of sodium bicarbonate (2.5%, 12.2 l). The solution was extracted with 18.6 l of a mixture of THF and ethyl acetate (2:1 v/v). 37% HCl (130 ml) were added to the organic layer in order to precipitate the monohydrate of the (6-diethylaminomethyl-naphthalen-2-yl)-methyl ester hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid. If necessary, this operation can be repeated several times to remove any residues of the original acid.

Finally, the solid was dried under vacuum (approximately 30 mbar, 50° C.), producing 0.85 kg (60%) of compound (I).

HPLC purity: 99.5%; water content (Karl Fischer method): 3.8%; (argentometric) assay: 99.8%.

Elemental analysis
C % H % Cl % N %
Calculated for 60.56 6.35 7.45 8.83
C24H30ClN3O5
Found 61.06 6.48 7.48 8.90

 

…..

PATENT

http://www.google.co.in/patents/US20120302633

The hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid (6-dimethylamino methyl-2-naphtalenyl) ester, also known as ITF 2357 and having the International Non Proprietary Name (INN) of Givinostat® is an organic compound with immunosuppressive and anti-inflammatory activity,

…………………..

http://www.google.com/patents/US6034096

EXAMPLE 12

4-[6-(Diethylaminomethyl)naphth-2-ylmethyloxycarbamoyl]-benzohydroxamic acid hydrochloride

A. 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) (22.2 g, 115 mmol) was added to a solution of 2,6-naphthalenedicarboxylic acid (25 g, 115 mmol) and hydroxybenzotriazole (15.6 g, 115 mmol) in dimethylformamide (1800 ml) and the mixture was stirred at room temperature for 2 hours. Diethyl amine (34.3 ml, 345 mmol) was added and the solution was stirred overnight at room temperature. The solvent was then evaporated under reduced pressure and the crude was treated with 1N HCl (500 ml) and ethyl acetate (500 ml), insoluble compounds were filtered off and the phases were separated. The organic phase was extracted with 5% sodium carbonate (3×200 ml) and the combined aqueous solutions were acidified with concentrated HCl and extracted with ethyl acetate (3×200 ml). The organic solution was then washed with 1N HCl (6×100 ml), dried over anhydrous sodium sulphate and the solvent was removed under reduced pressure yielding 18.5 g (Yield 60%) of pure 6-(diethylaminocarbonyl)-2-naphthalenecarboxylic acid; m.p.=122-124° C.

1 H-NMR d 8.67 (s, 1H), 8.25-8.00 (m, 4H), 7.56 (d, 1H), 3.60-3.20 (m, 4H), 1.30-1.00 (m, 6H).

B. A solution of 6-(diethylaminocarbonyl)-2- naphthalenecarboxylic acid (18 g, 66 mmol) in THF (200 ml) was slowly added to a refluxing suspension of lithium aluminium hydride (7.5 g, 199 mmol) in THF (500 ml). The mixture was refluxed for an hour, then cooled at room temperature and treated with a mixture of THF (25 ml) and water (3.5 ml), with 20% sodium hydroxide (8.5 ml) and finally with water (33 ml). The white solid was filtered off and the solvent was removed under reduced pressure. Crude was dissolved in diethyl ether (200 ml) and extracted with 1N HCl (3×100 ml). The aqueous solution was treated with 32% sodium hydroxide and extracted with diethyl ether (3×100 ml). The organic solution was dried over anhydrous sodium sulphate and the solvent was removed under reduced pressure yielding 12.7 g (79% yield) of pure 6-(diethylaminomethyl)-2-naphthalenemethanol as thick oil.

1 H-NMR d 7.90-7.74 (m, 4H), 7.49 (m, 2H), 5.32 (t, 1H, exchange with D2 O), 4.68 (d, 2H), 3.69 (s, 2H), 2.52 (q, 4H), 1.01 (t, 6H).

C. A solution of 6-(diethylaminomethyl)-2-naphthalene-methanol (12.5 g, 51 mmol) and N,N’-disuccinimidyl carbonate (13.2 g, 51 mmol) in acetonitrile (250 ml) was stirred at room temperature for 3 hours, then the solvent was removed and the crude was dissolved in THF (110 ml). This solution was added to a solution of 4-amino benzoic acid (7.1 g, 51 mmol) and sodium carbonate (5.5 g, 51 mmol) in water (200 ml) and THF (100 ml). The mixture was stirred overnight at room temperature, then THF was removed under reduced pressure and the solution was treated with 1N HCl (102 ml, 102 mmol). The precipitate was filtered, dried under reduced pressure, tritured in diethyl ether and filtered yielding 13.2 g (yield 64%) of pure 4-[6-(diethylaminomethyl)naphth-2-ylmethyloxycarbamoyl]-benzoic acid; m.p.=201-205° C. (dec.)

1 H-NMR d 10.26 (s, 1H), 8.13 (s, 1H), 8.05-7.75 (m, 6H), 7.63 (m, 3H), 5.40 (s, 2H), 4.32 (s, 2H), 2.98 (q, 4H), 1.24 (t, 6H).

D. A solution of 4-[6-(diethylaminomethyl)naphth-2-ylmethyloxycarbamoyl]benzoic acid (13.1 g, 32 mmol) and thionyl chloride (7 ml, 96 mmol) in chloroform (300 ml) was refluxed for 4 hours, then the solvent and thionyl chloride were evaporated. Crude was dissolved in chloroform (100 ml) and evaporated to dryness three times. Crude was added as solid to a solution of hydroxylamine hydrochloride (2.7 g, 39 mmol) and sodium bicarbonate (5.4 g, 64 mmol) and 1N sodium hydroxide (39 ml, 39 mmol) in water (150 ml) and THF (50 ml). The mixture was stirred overnight at room temperature, then THF was removed under reduced pressure and the aqueous phase was extracted with ethyl acetate (3×100 ml). The combined organic phases were dried over anhydrous sodium sulphate and the solvent was removed under reduced pressure. Crude was dissolved in THF and treated with a 1.5 N etheric solution of HCl. The solid product was filtered and dried yielding 6 g (yield 41%) of pure 4-[6-(diethylaminomethyl)naphth-2-ylmethyloxycarbamoyl]benzohydroxamic acid hydrochloride as white solid; m.p.=162-165° C., (dec.)

1 H-NMR d 11.24 (s, 1H, exchange with D2 O), 10.88 (s, 1H, exchange with D2 O), 10.16 (s, 1H), 8.98 (bs, 1H, exchange with D2 O), 8.21 (s, 1H), 8.10-7.97 (m, 3H), 7.89 (d, 1H), 7.80-7.55 (m, 5H), 5.39 (s, 2H), 4.48 (d, 2H), 3.09 (m, 4H), 1.30 (t, 6H).

http://www.molbase.com/

Some nmr predictions

CAS NO. 497833-27-9, [6-(diethylaminomethyl)naphthalen-2-yl]methyl N-[4-(hydroxycarbamoyl)phenyl]carbamate H-NMR spectral analysis

[6-(diethylaminomethyl)naphthalen-2-yl]methyl N-[4-(hydroxycarbamoyl)phenyl]carbamate NMR spectra analysis, Chemical CAS NO. 497833-27-9 NMR spectral analysis, [6-(diethylaminomethyl)naphthalen-2-yl]methyl N-[4-(hydroxycarbamoyl)phenyl]carbamate H-NMR spectrum

13 C NMR PREDICTIONS

 

 

[6-(diethylaminomethyl)naphthalen-2-yl]methyl N-[4-(hydroxycarbamoyl)phenyl]carbamate NMR spectra analysis, Chemical CAS NO. 497833-27-9 NMR spectral analysis, [6-(diethylaminomethyl)naphthalen-2-yl]methyl N-[4-(hydroxycarbamoyl)phenyl]carbamate C-NMR spectrum

 

COSY NMR…..http://www.nmrdb.org/

COSY NMR prediction (3)

HMBC /HSQC

HMBC, HSQC NMR prediction

References

 1

 

 

  1. Guerini V, Barbui V, Spinelli O, et al. (April 2008). “The histone deacetylase inhibitor ITF2357 selectively targets cells bearing mutated JAK2(V617F)”. Leukemia 22 (4): 740–7. doi:10.1038/sj.leu.2405049. PMID 18079739.

Further reading

US6034096 12 May 1997 7 Mar 2000 Italfarmaco S.P.A. Compounds with anti-inflammatory and immunosuppressive activities

 

WO1997043251A1 May 12, 1997 Nov 20, 1997 Italfarmaco Spa Compounds with anti-inflammatory and immunosuppressive activities
WO2004063146A1 Jan 7, 2004 Jul 29, 2004 Italfarmaco Spa Hydroxamic acid derivatives having anti-inflammatory action
WO2004065355A1 Jan 8, 2004 Aug 5, 2004 Italfarmaco Spa Monohydrate hydrochloride of the 4-hydroxycarbamoyl-phenyl)-carbamic acid (6-diethylaminomethyl-naphtalen-2-yl) ester
WO2006003068A2 Jun 7, 2005 Jan 12, 2006 Italfarmaco Spa Alpha-amino acid derivatives with antiinflammatory activity
WO2008097654A1 Feb 8, 2008 Aug 14, 2008 Nancie M Archin Methods of using saha for treating hiv infection
Citing Patent Filing date Publication date Applicant Title
US8518988 * 3 Dec 2010 27 Aug 2013 Chemi Spa Polymorph of the hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid (6-dimethylamino methyl-2-naphthalenyl) ester
US20120302633 * 3 Dec 2010 29 Nov 2012 Chemi Spa Novel polymorph of the hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid (6-dimethylamino methyl-2-naphthalenyl) ester
WO2011092556A1 3 Dec 2010 4 Aug 2011 Chemi Spa Novel polymorph of the hydrochloride of the (4-hydroxycarbamoyl-phenyl)-carbamic acid (6-dimethylamino methyl-2-naphtalenyl) ester
Givinostat
Givinostat structure.svg
Systematic (IUPAC) name
{6-[(diethylamino)methyl]naphthalen-2-yl}methyl [4-(hydroxycarbamoyl)phenyl]carbamate
Clinical data
Legal status
Routes Oral
Identifiers
CAS number 497833-27-9 Yes
ATC code None
PubChem CID 9804992
ChemSpider 7980752 
UNII 5P60F84FBH Yes
Chemical data
Formula C24H27N3O4 
Molecular mass 421.489 g/mol
 
Italfarmaco S.p.A.
Logo
Stato Italia Italia
Tipo Società per azioni
Fondazione 1938 a Milano
Fondata da Gastone De Santis
Sede principale Milano
Filiali Spagna SpagnaPortogallo Portogallo
Grecia GreciaRussia Russia
Cile CileBrasile Brasile
Turchia Turchia
Persone chiave Francesco De Santis, [Presidente Holding]
Settore sanità
Prodotti Farmaci
Fatturato >500 milioni di Euro (gruppo) (2011)
Dipendenti >1900 (gruppo) (2011)
Sito web www.italfarmaco.com

MILAN ITALY

FAVIPIRAVIR, ファビピラビル


 

FAVIPIRAVIR
Toyama (Originator)
RNA-Directed RNA Polymerase (NS5B) Inhibitors
Chemical Formula:   C5H4FN3O2
CAS #:   259793-96-9
Molecular Weight:   157.1
   

ANTI-INFLUENZA COMPOUND

clinical trials    http://clinicaltrials.gov/search/intervention=Favipiravir
Chemical Name:   6-fluoro-3-hydroxy-2-pyrazinecarboxamide
     
Synonyms:   T-705, T705, Favipiravir

ChemSpider 2D Image | favipiravir | C5H4FN3O2

  • Molecular FormulaC5H4FN3O2
  • Average mass157.103 Da
259793-96-9 [RN]
2-Pyrazinecarboxamide, 6-fluoro-3,4-dihydro-3-oxo-
 
6-Fluoro-3-hydroxypyrazine-2-carboxamide
6-Fluoro-3-oxo-3,4-dihydro-2-pyrazinecarboxamide
 
8916
Avigan

ファビピラビル
Favipiravir

6-Fluoro-3-hydroxypyrazine-2-carboxamide

C5H4FN3O2 : 157.1
[259793-96-9]

https://www.pmda.go.jp/files/000210319.pdf

 

The drug substance is a white to light yellow powder. It is sparingly soluble in acetonitrile and in methanol, and slightly soluble in water and in ethanol (99.5). It is slightly soluble at pH 2.0 to 5.5 and sparingly soluble at pH 5.5 to 6.1. The drug substance is not hygroscopic at 25°C/51% to 93%RH. The melting point is 187°C to 193°C, and the dissociation constant (pKa) is 5.1 due to the hydroxyl group of favipiravir. Measurement results on the partition ratio of favipiravir in water/octanol at 25°C indicate that favipiravir tends to be distributed in the 1-octanol phase at pH 2 to 4 and in the water phase at pH 5 to 13.

Any batch manufactured by the current manufacturing process is in Form A. The stability study does not show any change in crystal form over time; and a change from Form A to Form B is unlikely.

Experimental Properties

PROPERTY VALUE SOURCE
melting point (°C) 187℃ to 193℃ https://www.pmda.go.jp/files/000210319.pdf
water solubility slightly soluble in water https://www.pmda.go.jp/files/000210319.pdf
pKa 5.1 https://www.pmda.go.jp/files/000210319.pdf
 
T-705 is an RNA-directed RNA polymerase (NS5B) inhibitor which has been filed for approval in Japan for the oral treatment of influenza A (including avian and H1N1 infections) and for the treatment of influenza B infection.
The compound is a unique viral RNA polymerase inhibitor, acting on viral genetic copying to prevent its reproduction, discovered by Toyama Chemical. In 2005, Utah State University carried out various studies under its contract with the National Institute of Allergy and Infectious Diseases (NIAID) and demonstrated that T-705 has exceptionally potent activity in mouse infection models of H5N1 avian influenza.
T-705 (Favipiravir) is an antiviral pyrazinecarboxamide-based, inhibitor of of the influenza virus with an EC90 of 1.3 to 7.7 uM (influenza A, H5N1). EC90 ranges for other influenza A subtypes are 0.19-1.3 uM, 0.063-1.9 uM, and 0.5-3.1 uM for H1N1, H2N2, and H3N2, respectively. T-705 also exhibits activity against type B and C viruses, with EC90s of 0.25-0.57 uM and 0.19-0.36 uM, respectively. (1) Additionally, T-705 has broad activity against arenavirus, bunyavirus, foot-and-mouth disease virus, and West Nile virus with EC50s ranging from 5 to 300 uM.
Studies show that T-705 ribofuranosyl triphosphate is the active form of T-705 and acts like purines or purine nucleosides in cells and does not inhibit DNA synthesis
In 2012, MediVector was awarded a contract from the U.S. Department of Defense’s (DOD) Joint Project Manager Transformational Medical Technologies (JPM-TMT) to further develop T-705 (favipiravir), a broad-spectrum therapeutic against multiple influenza viruses.
Several novel anti-influenza compounds are in various phases of clinical development. One of these, T-705 (favipiravir), has a mechanism of action that is not fully understood but is suggested to target influenza virus RNA-dependent RNA polymerase. We investigated the mechanism of T-705 activity against influenza A (H1N1) viruses by applying selective drug pressure over multiple sequential passages in MDCK cells. We found that T-705 treatment did not select specific mutations in potential target proteins, including PB1, PB2, PA, and NP. Phenotypic assays based on cell viability confirmed that no T-705-resistant variants were selected. In the presence of T-705, titers of infectious virus decreased significantly (P < 0.0001) during serial passage in MDCK cells inoculated with seasonal influenza A (H1N1) viruses at a low multiplicity of infection (MOI; 0.0001 PFU/cell) or with 2009 pandemic H1N1 viruses at a high MOI (10 PFU/cell). There was no corresponding decrease in the number of viral RNA copies; therefore, specific virus infectivity (the ratio of infectious virus yield to viral RNA copy number) was reduced. Sequence analysis showed enrichment of G→A and C→T transversion mutations, increased mutation frequency, and a shift of the nucleotide profiles of individual NP gene clones under drug selection pressure. Our results demonstrate that T-705 induces a high rate of mutation that generates a nonviable viral phenotype and that lethal mutagenesis is a key antiviral mechanism of T-705. Our findings also explain the broad spectrum of activity of T-705 against viruses of multiple families.

Favipiravir, also known as T-705Avigan, or favilavir is an antiviral drug being developed by Toyama Chemical (Fujifilm group) of Japan with activity against many RNA viruses. Like certain other experimental antiviral drugs (T-1105 and T-1106), it is a pyrazinecarboxamide derivative. In experiments conducted in animals Favipiravir has shown activity against influenza virusesWest Nile virusyellow fever virusfoot-and-mouth disease virus as well as other flavivirusesarenavirusesbunyaviruses and alphaviruses.[1]Activity against enteroviruses[2] and Rift Valley fever virus has also been demonstrated.[3] Favipiravir has showed limited efficacy against Zika virus in animal studies, but was less effective than other antivirals such as MK-608.[4] The agent has also shown some efficacy against rabies,[5] and has been used experimentally in some humans infected with the virus.[6]

In February 2020 Favipiravir was being studied in China for experimental treatment of the emergent COVID-19 (novel coronavirus)disease.[7][8] On March 17 Chinese officials suggested the drug had been effective in treating COVID in Wuhan and Shenzhen.[9][10]

Discovered by Toyama Chemical Co., Ltd. in Japan, favipiravir is a modified pyrazine analog that was initially approved for therapeutic use in resistant cases of influenza.7,9 The antiviral targets RNA-dependent RNA polymerase (RdRp) enzymes, which are necessary for the transcription and replication of viral genomes.7,12,13

Not only does favipiravir inhibit replication of influenza A and B, but the drug shows promise in the treatment of influenza strains that are resistant to neuramidase inhibitors, as well as avian influenza.9,19 Favipiravir has been investigated for the treatment of life-threatening pathogens such as Ebola virus, Lassa virus, and now COVID-19.10,14,15

Mechanism of action

The mechanism of its actions is thought to be related to the selective inhibition of viral RNA-dependent RNA polymerase.[11] Other research suggests that favipiravir induces lethal RNA transversion mutations, producing a nonviable viral phenotype.[12] Favipiravir is a prodrug that is metabolized to its active form, favipiravir-ribofuranosyl-5′-triphosphate (favipiravir-RTP), available in both oral and intravenous formulations.[13][14] Human hypoxanthine guanine phosphoribosyltransferase (HGPRT) is believed to play a key role in this activation process.[15] Favipiravir does not inhibit RNA or DNA synthesis in mammalian cells and is not toxic to them.[1] In 2014, favipiravir was approved in Japan for stockpiling against influenza pandemics.[16] However, favipiravir has not been shown to be effective in primary human airway cells, casting doubt on its efficacy in influenza treatment.[17]

Approval status

In 2014, Japan approved Favipiravir for treating viral strains unresponsive to current antivirals.[18]

In March 2015, the US Food and Drug Administration completed a Phase III clinical trial studying the safety and efficacy of Favipiravir in the treatment of influenza.[19]

Ebola virus trials

Some research has been done suggesting that in mouse models Favipiravir may have efficacy against Ebola. Its efficacy against Ebola in humans is unproven.[20][21][22] During the 2014 West Africa Ebola virus outbreak, it was reported that a French nurse who contracted Ebola while volunteering for MSF in Liberia recovered after receiving a course of favipiravir.[23] A clinical trial investigating the use of favipiravir against Ebola virus disease was started in Guéckédou, Guinea, during December 2014.[24] Preliminary results showed a decrease in mortality rate in patients with low-to-moderate levels of Ebola virus in the blood, but no effect on patients with high levels of the virus, a group at a higher risk of death.[25] The trial design has been criticised by Scott Hammer and others for using only historical controls.[26] The results of this clinical trial were presented in February 2016 at the annual Conference on Retroviruses and Opportunistic Infections (CROI) by Daouda Sissoko[27] and published on March 1, 2016 in PLOS Medicine.[28]

SARS-CoV-2 virus disease

In March 2020, Chinese officials suggested Favipiravir may be effective in treating COVID-19.[29]

SYN

https://link.springer.com/article/10.1007/s11696-018-0654-9

Image result for FAVIPIRAVIR SYNTHESIS

Image result for FAVIPIRAVIR SYNTHESIS

Electronic supplementary material

 

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOCX 1315 kb)

Ref

https://pdfs.semanticscholar.org/be8e/cb882b99204983d2f60077c7ab8b53f4d62c.pdf

Drug Discoveries & Therapeutics. 2014; 8(3):117-120.

As a RNA polymerase inhibitor, 6-fluoro-3-hydroxypyrazine-2-carboxamide commercially named favipiravir has been proved to have potent inhibitory activity against RNA viruses in vitro and in vivo. A four-step synthesis of the compound is described in this article, amidation, nitrification, reduction and fluorination with an overall yield of about 8%. In addition, we reported the crystal structure of the title compound. The molecule is almost planar and the intramolecular O−H•••O hydrogen bond makes a 6-member ring. In the crystal, molecules are packing governed by both hydrogen bonds and stacking interactions.

2.2.1. Preparation of 3-hydroxypyrazine-2-carboxamide To a suspension of 3-hydroxypyrazine-2-carboxylic acid (1.4 g, 10 mmol) in 150 mL MeOH, SOCl2 was added dropwise at 40°C with magnetic stirring for 6 h resulting in a bright yellow solution. The reaction was then concentrated to dryness. The residue was dissolved in 50 mL 25% aqueous ammonia and stirred overnight to get a suspension. The precipitate was collected and dried. The solid yellow-brown crude product was recrystallization with 50 mL water to get the product as pale yellow crystals (1.1 g, 78%). mp = 263-265°C. 1 H-NMR (300 MHz, DMSO): δ 13.34 (brs, 1H, OH), 8.69 (s, 1H, pyrazine H), 7.93-8.11 (m, 3H, pyrazine H, CONH2). HRMS (ESI): m/z [M + H]+ calcd for C5H6N3O2 + : 140.0460; found: 140.0457.

2.2.2. Preparation of 3-hydroxy-6-nitropyrazine-2- carboxamide In the solution of 3-hydroxypyrazine-2-carboxamide (1.0 g, 7 mmol) in 6 mL concentrate sulfuric acid under ice-cooling, potassium nitrate (1.4 g, 14 mmol) was added. After stirring at 40°C for 4 h, the reaction mixture was poured into 60 mL water. The product was collected by fi ltration as yellow solid (0.62 g, 48%). mp = 250-252°C. 1 H-NMR (600 MHz, DMSO): δ 12.00- 15.00 (br, 1H, OH), 8.97 (s, 1H, pyrazine H), 8.32 (s, 1H, CONH2), 8.06 (s, 1H, CONH2). 13C-NMR (75 MHz, DMSO): δ 163.12, 156.49, 142.47, 138.20, 133.81. HRMS (ESI): m/z [M + H]+ calcd for C5H5N4O4 + : 185.0311; found: 185.0304.

2.2.3. Preparation of 6-amino-3-hydroxypyrazine-2- carboxamide 3-Hydroxy-6-nitropyrazine-2-carboxamide (0.6 g, 3.3 mmol) and a catalytic amount of raney nickel were suspended in MeOH, then hydrazine hydrate was added dropwise. The resulting solution was refl uxed 2 h, cooled, filtered with diatomite, and then MeOH is evaporated in vacuo to get the crude product as dark brown solid without further purification (0.4 g, 77%). HRMS (ESI): m/z [M + H]+ calcd for C5H7N4O2 + : 155.0569; found:155.0509.

2.2.4. Preparation of 6-fluoro-3-hydroxypyrazine-2- carboxamide To a solution of 6-amino-3-hydroxypyrazine-2- carboxamide (0.4 g, 2.6 mmol) in 3 mL 70% HFpyridine aqueous at -20°C under nitrogen atmosphere, sodium nitrate (0.35 g, 5.2 mmol) was added. After stirring 20 min, the solution was warmed to room temperature for another one hour. Then 20 mL ethyl acetate/water (1:1) were added, after separation of the upper layer, the aqueous phase is extracted with four 20 mL portions of ethyl acetate. The combined extracts are dried with anhydrous magnesium sulfate and concentrated to dryness to get crude product as oil. The crude product was purified by chromatography column as white solid (0.12 g, 30%). mp = 178-180°C. 1 H-NMR (600 MHz, DMSO): δ 12.34 (brs, 1H, OH), 8.31 (d, 1H, pyrazine H, J = 8.0 Hz), 7.44 (s, 1H, CONH2), 5.92 (s, 1H, CONH2). 13C-NMR (75 MHz, DMSO): δ 168.66, 159.69, 153.98, 150.76, 135.68. HRMS (ESI): m/z [M + H]+ calcd for C5H5FN3O2 + : 158.0366; found: 158.0360.

SEE

Chemical Papers (2019), 73(5), 1043-1051.

PAPER

Medicinal chemistry (Shariqah (United Arab Emirates)) (2018), 14(6), 595-603

http://www.eurekaselect.com/158990/article

PATENT

CN 107641106

PAPER

Chemical Papers (2017), 71(11), 2153-2158.

https://link.springer.com/article/10.1007%2Fs11696-017-0208-6

Image result for A practical and step-economic route to Favipiravir

Image result for A practical and step-economic route to Favipiravir

Image result for A practical and step-economic route to Favipiravir

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOCX 514 kb)

References

  1.  Furuta, Y.; Takahashi, K.; Shiraki, K.; Sakamoto, K.; Smee, D. F.; Barnard, D. L.; Gowen, B. B.; Julander, J. G.; Morrey, J. D. (2009). “T-705 (favipiravir) and related compounds: Novel broad-spectrum inhibitors of RNA viral infections”. Antiviral Research 82 (3): 95–102. doi:10.1016/j.antiviral.2009.02.198PMID 19428599edit
  2. WO 2000010569
  3. WO 2008099874
  4. WO 201009504
  5. WO 2010104170
  6. WO 2012063931

Process route
OH
OH
hydrolysis
CLIP
Influenza virus is a central virus of the cold syndrome, which has attacked human being periodically to cause many deaths amounting to tens millions. Although the number of deaths shows a tendency of decrease in the recent years owing to the improvement in hygienic and nutritive conditions, the prevalence of influenza is repeated every year, and it is apprehended that a new virus may appear to cause a wider prevalence.
For prevention of influenza virus, vaccine is used widely, in addition to which low molecular weight substances such as Amantadine and Ribavirin are also used

CLIP

Synthesis of Favipiravir
ZHANG Tao1, KONG Lingjin1, LI Zongtao1,YUAN Hongyu1, XU Wenfang2*
(1. Shandong Qidu PharmaceuticalCo., Ltd., Linzi 255400; 2. School of Pharmacy, Shandong University, Jinan250012)
ABSTRACT: Favipiravir was synthesized from3-amino-2-pyrazinecarboxylic acid by esterification, bromination with NBS,diazotization and amination to give 6-bromo-3-hydroxypyrazine-2-carboxamide,which was subjected to chlorination with POCl3, fluorination with KF, andhydrolysis with an overall yield of about 22%.

PATENT
US6787544

Figure US06787544-20040907-C00005

subs            G1 G2 G3 G4 R2
    compd 32 N CH C—CF3 N H

…………………
EP2192117
Figure US20100286394A1-20101111-C00001
Example 1-1

Figure US20100286394A1-20101111-C00002

To a 17.5 ml N,N-dimethylformamide solution of 5.0 g of 3,6-difluoro-2-pyrazinecarbonitrile, a 3.8 ml water solution of 7.83 g of potassium acetate was added dropwise at 25 to 35° C., and the solution was stirred at the same temperature for 2 hours. 0.38 ml of ammonia water was added to the reaction mixture, and then 15 ml of water and 0.38 g of active carbon were added. The insolubles were filtered off and the filter cake was washed with 11 ml of water. The filtrate and the washing were joined, the pH of this solution was adjusted to 9.4 with ammonia water, and 15 ml of acetone and 7.5 ml of toluene were added. Then 7.71 g of dicyclohexylamine was added dropwise and the solution was stirred at 20 to 30° C. for 45 minutes. Then 15 ml of water was added dropwise, the solution was cooled to 10° C., and the precipitate was filtered and collected to give 9.44 g of dicyclohexylamine salt of 6-fluoro-3-hydroxy-2-pyradinecarbonitrile as a lightly yellowish white solid product.
1H-NMR (DMSO-d6) δ values: 1.00-1.36 (10H, m), 1.56-1.67 (2H, m), 1.67-1.81 (4H, m), 1.91-2.07 (4H, m), 3.01-3.18 (2H, m), 8.03-8.06 (1H, m), 8.18-8.89 (1H, broad)
Example 1-2
4.11 ml of acetic acid was added at 5 to 15° C. to a 17.5 ml N,N-dimethylformamide solution of 5.0 g of 3,6-difluoro-2-pyrazinecarbonitrile. Then 7.27 g of triethylamine was added dropwise and the solution was stirred for 2 hours. 3.8 ml of water and 0.38 ml of ammonia water were added to the reaction mixture, and then 15 ml of water and 0.38 g of active carbon were added. The insolubles were filtered off and the filter cake was washed with 11 ml of water. The filtrate and the washing were joined, the pH of the joined solution was adjusted to 9.2 with ammonia water, and 15 ml of acetone and 7.5 ml of toluene were added to the solution, followed by dropwise addition of 7.71 g of dicyclohexylamine. Then 15 ml of water was added dropwise, the solution was cooled to 5° C., and the precipitate was filtered and collected to give 9.68 g of dicyclohexylamine salt of 6-fluoro-3-hydroxy-2-pyrazinecarbonitrile as a slightly yellowish white solid product.
Examples 2 to 5
The compounds shown in Table 1 were obtained in the same way as in Example 1-1.

TABLE 1
 
Figure US20100286394A1-20101111-C00003
 
Example No. Organic amine Example No. Organic amine
 
2 Dipropylamine 4 Dibenzylamine
3 Dibutylamine 5 N-benzylmethylamine
 

Dipropylamine salt of 6-fluoro-3-hydroxy-2-pyrazinecarbonitrile
1H-NMR (DMSO-d6) 6 values: 0.39 (6H, t, J=7.5 Hz), 1.10 (4H, sex, J=7.5 Hz), 2.30-2.38 (4H, m), 7.54 (1H, d, J=8.3 Hz)
Dibutylamine salt of 6-fluoro-3-hydroxy-2-pyrazinecarbonitrile
1H-NMR (DMSO-d6) 6 values: 0.36 (6H, t, J=7.3 Hz), 0.81 (4H, sex, J=7.3 Hz), 0.99-1.10 (4H, m), 2.32-2.41 (4H, m), 7.53 (1H, d, J=8.3 Hz)
Dibenzylamine salt of 6-fluoro-3-hydroxy-2-pyrazinecarbonitrile
1H-NMR (DMSO-d6) δ values: 4.17 (4H, s), 7.34-7.56 (10H, m), 8.07 (1H, d, J=8.3 Hz)
N-benzylmethylamine salt of 6-fluoro-3-hydroxy-2-pyrazinecarbonitrile
1H-NMR (DMSO-d6) δ values: 2.57 (3H, s), 4.14 (2H, s), 7.37-7.53 (5H, m), 8.02-8.08 (1H, m)
Preparation Example 1

Figure US20100286394A1-20101111-C00004

300 ml of toluene was added to a 600 ml water solution of 37.5 g of sodium hydroxide. Then 150 g of dicyclohexylamine salt of 6-fluoro-3-hydroxy-2-pyrazinecarbonitrile was added at 15 to 25° C. and the solution was stirred at the same temperature for 30 minutes. The water layer was separated and washed with toluene, and then 150 ml of water was added, followed by dropwise addition of 106 g of a 30% hydrogen peroxide solution at 15 to 30° C. and one-hour stirring at 20 to 30° C. Then 39 ml of hydrochloric acid was added, the seed crystals were added at 40 to 50° C., and 39 ml of hydrochloric acid was further added dropwise at the same temperature. The solution was cooled to 10° C. the precipitate was filtered and collected to give 65.6 g of 6-fluoro-3-hydroxy-2-pyrazinecarboxamide as a slightly yellowish white solid.
1H-NMR (DMSO-d6) δ values: 8.50 (1H, s), 8.51 (1H, d, J=7.8 Hz), 8.75 (1H, s), 13.41 (1H, s)

CLIP
jan 2014

Investigational flu treatment drug has broad-spectrum potential to fight multiple viruses
First patient enrolled in the North American Phase 3 clinical trials for investigational flu treatment drug
BioDefense Therapeutics (BD Tx)—a Joint Product Management office within the U.S. Department of Defense (DoD)—announced the first patient enrolled in the North American Phase 3 clinical trials for favipiravir (T-705a). The drug is an investigational flu treatment candidate with broad-spectrum potential being developed by BD Tx through a contract with Boston-based MediVector, Inc.
Favipiravir is a novel, antiviral compound that works differently than anti-flu drugs currently on the market. The novelty lies in the drug’s selective disruption of the viralRNA replication and transcription process within the infected cell to stop the infection cycle.
“Favipiravir has proven safe and well tolerated in previous studies,” said LTC Eric G. Midboe, Joint Product Manager for BD Tx. “This first patient signifies the start of an important phase in favipiravir’s path to U.S. Food and Drug Administration (FDA) approval for flu and lays the groundwork for future testing against other viruses of interest to the DoD.”
In providing therapeutic solutions to counter traditional, emerging, and engineered biological threats, BD Tx chose favipiravir not only because of its potential effectiveness against flu viruses, but also because of its demonstrated broad-spectrum potential against multiple viruses.  In addition to testing favipiravir in the ongoing influenzaprogram, BD Tx is testing the drug’s efficacy against the Ebola virus and other viruses considered threats to service members. In laboratory testing, favipiravir was found to be effective against a wide variety of RNA viruses in infected cells and animals.
“FDA-approved, broad-spectrum therapeutics offer the fastest way to respond to dangerous and potentially lethal viruses,” said Dr. Tyler Bennett, Assistant Product Manager for BD Tx.
MediVector is overseeing the clinical trials required by the  FDA  to obtain drug licensure. The process requires safety data from at least 1,500 patients treated for flu at the dose and duration proposed for marketing of the drug. Currently, 150 trial sites are planned throughout the U.S.
SOURCE BioDefense Therapeutics
 
Malpani Y, Achary R, Kim SY, Jeong HC, Kim P, Han SB, Kim M, Lee CK, Kim JN, Jung YS.
Eur J Med Chem. 2013 Apr;62:534-44. doi: 10.1016/j.ejmech.2013.01.015. Epub 2013 Jan 29.

 

US3631036 * Nov 4, 1969 Dec 28, 1971 American Home Prod 5-amino-2 6-substituted-7h-pyrrolo(2 3-d) pyrimidines and related compounds
US3745161 * Apr 20, 1970 Jul 10, 1973 Merck & Co Inc Phenyl-hydroxy-pyrazine carboxylic acids and derivatives
US4404203 * May 14, 1981 Sep 13, 1983 Warner-Lambert Company Substituted 6-phenyl-3(2H)-pyridazinones useful as cardiotonic agents
US4545810 * Mar 25, 1983 Oct 8, 1985 Sds Biotech Corporation Herbicidal and plant growth regulant diphenylpyridazinones
US4565814 * Jan 18, 1984 Jan 21, 1986 Sanofi Pyridazine derivatives having a psychotropic action and compositions
US4661145 * Sep 20, 1984 Apr 28, 1987 Rohm And Haas Company Plant growth regulating 1-aryl-1,4-dihydro-4-oxo(thio)-pyridazines
US5420130 May 16, 1994 May 30, 1995 Synthelabo 2-aminopyrazine-5-carboxamide derivatives, their preparation and their application in therapeutics
US5459142 * Aug 23, 1993 Oct 17, 1995 Otsuka Pharmaceutical Co., Ltd. Pyrazinyl and piperazinyl substituted pyrazine compounds
US5597823 Jun 5, 1995 Jan 28, 1997 Abbott Laboratories Tricyclic substituted hexahydrobenz [e]isoindole alpha-1 adrenergic antagonists
US6159980 * Sep 15, 1997 Dec 12, 2000 Dupont Pharmaceuticals Company Pyrazinones and triazinones and their derivatives thereof
EP0023358A1 * Jul 28, 1980 Feb 4, 1981 Rohm And Haas Company Process for the preparation of pyridazine derivatives
GB1198688A       Title not available
HU9401512A       Title not available
JPH09216883A *       Title not available
JPS5620576A       Title not available

 

  1. Jump up to:a b Furuta Y, Takahashi K, Shiraki K, Sakamoto K, Smee DF, Barnard DL, Gowen BB, Julander JG, Morrey JD (June 2009). “T-705 (favipiravir) and related compounds: Novel broad-spectrum inhibitors of RNA viral infections”. Antiviral Research82 (3): 95–102. doi:10.1016/j.antiviral.2009.02.198PMID 19428599.
  2. ^ Furuta Y, Gowen BB, Takahashi K, Shiraki K, Smee DF, Barnard DL (November 2013). “Favipiravir (T-705), a novel viral RNA polymerase inhibitor”Antiviral Research100 (2): 446–54. doi:10.1016/j.antiviral.2013.09.015PMC 3880838PMID 24084488.
  3. ^ Caroline AL, Powell DS, Bethel LM, Oury TD, Reed DS, Hartman AL (April 2014). “Broad spectrum antiviral activity of favipiravir (T-705): protection from highly lethal inhalational Rift Valley Fever”PLoS Neglected Tropical Diseases8 (4): e2790. doi:10.1371/journal.pntd.0002790PMC 3983105PMID 24722586.
  4. ^ Mumtaz N, van Kampen JJ, Reusken CB, Boucher CA, Koopmans MP (2016). “Zika Virus: Where Is the Treatment?”Current Treatment Options in Infectious Diseases8 (3): 208–211. doi:10.1007/s40506-016-0083-7PMC 4969322PMID 27547128.
  5. ^ Yamada K, Noguchi K, Komeno T, Furuta Y, Nishizono A (April 2016). “Efficacy of Favipiravir (T-705) in Rabies Postexposure Prophylaxis”The Journal of Infectious Diseases213 (8): 1253–61. doi:10.1093/infdis/jiv586PMC 4799667PMID 26655300.
  6. ^ Murphy J, Sifri CD, Pruitt R, Hornberger M, Bonds D, Blanton J, Ellison J, Cagnina RE, Enfield KB, Shiferaw M, Gigante C, Condori E, Gruszynski K, Wallace RM (January 2019). “Human Rabies – Virginia, 2017”MMWR. Morbidity and Mortality Weekly Report67(5152): 1410–1414. doi:10.15585/mmwr.mm675152a2PMC 6334827PMID 30605446.
  7. ^ Li G, De Clercq E. Therapeutic options for the 2019 novel coronavirus (2019-nCoV). Nature Reviews Drug Discovery 2020 Feb doi:10.1038/d41573-020-00016-0
  8. ^ BRIEF-Corrected-Zhejiang Hisun Pharma gets approval for clinical trial to test flu drug Favipiravir for pneumonia caused by new coronavirus. Reuters Healthcare, February 16, 2020.
  9. ^ [1]NHK World News ‘China: Avigan effective in tackling coronavirus’
  10. ^ Huaxia. Favipiravir shows good clinical efficacy in treating COVID-19: official. Xinhuanet.com, 17 March 2020
  11. ^ Jin Z, Smith LK, Rajwanshi VK, Kim B, Deval J (2013). “The ambiguous base-pairing and high substrate efficiency of T-705 (Favipiravir) Ribofuranosyl 5′-triphosphate towards influenza A virus polymerase”PLOS ONE8 (7): e68347. Bibcode:2013PLoSO…868347Jdoi:10.1371/journal.pone.0068347PMC 3707847PMID 23874596.
  12. ^ Baranovich T, Wong SS, Armstrong J, Marjuki H, Webby RJ, Webster RG, Govorkova EA (April 2013). “T-705 (favipiravir) induces lethal mutagenesis in influenza A H1N1 viruses in vitro”Journal of Virology87 (7): 3741–51. doi:10.1128/JVI.02346-12PMC 3624194PMID 23325689.
  13. ^ Guedj J, Piorkowski G, Jacquot F, Madelain V, Nguyen TH, Rodallec A, et al. (March 2018). “Antiviral efficacy of favipiravir against Ebola virus: A translational study in cynomolgus macaques”PLoS Medicine15 (3): e1002535. doi:10.1371/journal.pmed.1002535PMC 5870946PMID 29584730.
  14. ^ Smee DF, Hurst BL, Egawa H, Takahashi K, Kadota T, Furuta Y (October 2009). “Intracellular metabolism of favipiravir (T-705) in uninfected and influenza A (H5N1) virus-infected cells”The Journal of Antimicrobial Chemotherapy64 (4): 741–6. doi:10.1093/jac/dkp274PMC 2740635PMID 19643775.
  15. ^ Naesens L, Guddat LW, Keough DT, van Kuilenburg AB, Meijer J, Vande Voorde J, Balzarini J (October 2013). “Role of human hypoxanthine guanine phosphoribosyltransferase in activation of the antiviral agent T-705 (favipiravir)”. Molecular Pharmacology84 (4): 615–29. doi:10.1124/mol.113.087247PMID 23907213.
  16. ^ Koons C (7 August 2014). “Ebola Drug From Japan May Emerge Among Key Candidates”. Bloomberg.com.
  17. ^ Yoon JJ, Toots M, Lee S, Lee ME, Ludeke B, Luczo JM, et al. (August 2018). “Orally Efficacious Broad-Spectrum Ribonucleoside Analog Inhibitor of Influenza and Respiratory Syncytial Viruses”Antimicrobial Agents and Chemotherapy62 (8): e00766–18. doi:10.1128/AAC.00766-18PMC 6105843PMID 29891600.
  18. ^ Hayden, Frederick. “Influenza virus polymerase inhibitors in clinical development”Current Opinion in Infectious Diseasesdoi:10.1097/QCO.0000000000000532.
  19. ^ “Phase 3 Efficacy and Safety Study of Favipiravir for Treatment of Uncomplicated Influenza in Adults – T705US316”FDA. Retrieved 17 March 2020.
  20. ^ Gatherer D (August 2014). “The 2014 Ebola virus disease outbreak in West Africa”. The Journal of General Virology95 (Pt 8): 1619–24. doi:10.1099/vir.0.067199-0PMID 24795448.
  21. ^ Oestereich L, Lüdtke A, Wurr S, Rieger T, Muñoz-Fontela C, Günther S (May 2014). “Successful treatment of advanced Ebola virus infection with T-705 (favipiravir) in a small animal model”. Antiviral Research105: 17–21. doi:10.1016/j.antiviral.2014.02.014PMID 24583123.
  22. ^ Smither SJ, Eastaugh LS, Steward JA, Nelson M, Lenk RP, Lever MS (April 2014). “Post-exposure efficacy of oral T-705 (Favipiravir) against inhalational Ebola virus infection in a mouse model”. Antiviral Research104: 153–5. doi:10.1016/j.antiviral.2014.01.012PMID 24462697.
  23. ^ “First French Ebola patient leaves hospital”Reuters. 4 October 2016.
  24. ^ “Guinea: Clinical Trial for Potential Ebola Treatment Started in MSF Clinic in Guinea”. AllAfrica – All the Time. Retrieved 28 December 2014.
  25. ^ Fink S (4 February 2015). “Ebola Drug Aids Some in a Study in West Africa”The New York Times.
  26. ^ Cohen J (26 February 2015). “Results from encouraging Ebola trial scrutinized”Sciencedoi:10.1126/science.aaa7912. Retrieved 21 January 2016.
  27. ^ “Favipiravir in Patients with Ebola Virus Disease: Early Results of the JIKI trial in Guinea | CROI Conference”croiconference.org. Retrieved 2016-03-17.
  28. ^ Sissoko D, Laouenan C, Folkesson E, M’Lebing AB, Beavogui AH, Baize S, et al. (March 2016). “Experimental Treatment with Favipiravir for Ebola Virus Disease (the JIKI Trial): A Historically Controlled, Single-Arm Proof-of-Concept Trial in Guinea”PLoS Medicine13(3): e1001967. doi:10.1371/journal.pmed.1001967PMC 4773183PMID 26930627.
  29. ^ “Japanese flu drug ‘clearly effective’ in treating coronavirus, says China”The Guardian. 2020-03-18. Retrieved 2020-03-18.\
  1. Beigel J, Bray M: Current and future antiviral therapy of severe seasonal and avian influenza. Antiviral Res. 2008 Apr;78(1):91-102. doi: 10.1016/j.antiviral.2008.01.003. Epub 2008 Feb 4. [PubMed:18328578]
  2. Hsieh HP, Hsu JT: Strategies of development of antiviral agents directed against influenza virus replication. Curr Pharm Des. 2007;13(34):3531-42. [PubMed:18220789]
  3. Gowen BB, Wong MH, Jung KH, Sanders AB, Mendenhall M, Bailey KW, Furuta Y, Sidwell RW: In vitro and in vivo activities of T-705 against arenavirus and bunyavirus infections. Antimicrob Agents Chemother. 2007 Sep;51(9):3168-76. Epub 2007 Jul 2. [PubMed:17606691]
  4. Sidwell RW, Barnard DL, Day CW, Smee DF, Bailey KW, Wong MH, Morrey JD, Furuta Y: Efficacy of orally administered T-705 on lethal avian influenza A (H5N1) virus infections in mice. Antimicrob Agents Chemother. 2007 Mar;51(3):845-51. Epub 2006 Dec 28. [PubMed:17194832]
  5. Furuta Y, Takahashi K, Kuno-Maekawa M, Sangawa H, Uehara S, Kozaki K, Nomura N, Egawa H, Shiraki K: Mechanism of action of T-705 against influenza virus. Antimicrob Agents Chemother. 2005 Mar;49(3):981-6. [PubMed:15728892]
  6. Furuta Y, Takahashi K, Fukuda Y, Kuno M, Kamiyama T, Kozaki K, Nomura N, Egawa H, Minami S, Watanabe Y, Narita H, Shiraki K: In vitro and in vivo activities of anti-influenza virus compound T-705. Antimicrob Agents Chemother. 2002 Apr;46(4):977-81. [PubMed:11897578]
  7. Furuta Y, Komeno T, Nakamura T: Favipiravir (T-705), a broad spectrum inhibitor of viral RNA polymerase. Proc Jpn Acad Ser B Phys Biol Sci. 2017;93(7):449-463. doi: 10.2183/pjab.93.027. [PubMed:28769016]
  8. Venkataraman S, Prasad BVLS, Selvarajan R: RNA Dependent RNA Polymerases: Insights from Structure, Function and Evolution. Viruses. 2018 Feb 10;10(2). pii: v10020076. doi: 10.3390/v10020076. [PubMed:29439438]
  9. Hayden FG, Shindo N: Influenza virus polymerase inhibitors in clinical development. Curr Opin Infect Dis. 2019 Apr;32(2):176-186. doi: 10.1097/QCO.0000000000000532. [PubMed:30724789]
  10. Madelain V, Nguyen TH, Olivo A, de Lamballerie X, Guedj J, Taburet AM, Mentre F: Ebola Virus Infection: Review of the Pharmacokinetic and Pharmacodynamic Properties of Drugs Considered for Testing in Human Efficacy Trials. Clin Pharmacokinet. 2016 Aug;55(8):907-23. doi: 10.1007/s40262-015-0364-1. [PubMed:26798032]
  11. Nguyen TH, Guedj J, Anglaret X, Laouenan C, Madelain V, Taburet AM, Baize S, Sissoko D, Pastorino B, Rodallec A, Piorkowski G, Carazo S, Conde MN, Gala JL, Bore JA, Carbonnelle C, Jacquot F, Raoul H, Malvy D, de Lamballerie X, Mentre F: Favipiravir pharmacokinetics in Ebola-Infected patients of the JIKI trial reveals concentrations lower than targeted. PLoS Negl Trop Dis. 2017 Feb 23;11(2):e0005389. doi: 10.1371/journal.pntd.0005389. eCollection 2017 Feb. [PubMed:28231247]
  12. de Farias ST, Dos Santos Junior AP, Rego TG, Jose MV: Origin and Evolution of RNA-Dependent RNA Polymerase. Front Genet. 2017 Sep 20;8:125. doi: 10.3389/fgene.2017.00125. eCollection 2017. [PubMed:28979293]
  13. Shu B, Gong P: Structural basis of viral RNA-dependent RNA polymerase catalysis and translocation. Proc Natl Acad Sci U S A. 2016 Jul 12;113(28):E4005-14. doi: 10.1073/pnas.1602591113. Epub 2016 Jun 23. [PubMed:27339134]
  14. Nagata T, Lefor AK, Hasegawa M, Ishii M: Favipiravir: a new medication for the Ebola virus disease pandemic. Disaster Med Public Health Prep. 2015 Feb;9(1):79-81. doi: 10.1017/dmp.2014.151. Epub 2014 Dec 29. [PubMed:25544306]
  15. Rosenke K, Feldmann H, Westover JB, Hanley PW, Martellaro C, Feldmann F, Saturday G, Lovaglio J, Scott DP, Furuta Y, Komeno T, Gowen BB, Safronetz D: Use of Favipiravir to Treat Lassa Virus Infection in Macaques. Emerg Infect Dis. 2018 Sep;24(9):1696-1699. doi: 10.3201/eid2409.180233. Epub 2018 Sep 17. [PubMed:29882740]
  16. Delang L, Abdelnabi R, Neyts J: Favipiravir as a potential countermeasure against neglected and emerging RNA viruses. Antiviral Res. 2018 May;153:85-94. doi: 10.1016/j.antiviral.2018.03.003. Epub 2018 Mar 7. [PubMed:29524445]
  17. Nature Biotechnology: Coronavirus puts drug repurposing on the fast track [Link]
  18. Pharmaceuticals and Medical Devices Agency: Avigan (favipiravir) Review Report [Link]
  19. World Health Organization: Influenza (Avian and other zoonotic) [Link]
Favipiravir
Favipiravir.svg
Names
IUPAC name

 

5-Fluoro-2-hydroxypyrazine-3-carboxamide
Other names

 

T-705; Avigan; favilavir
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
PubChem CID
UNII
Properties
C5H4FN3O2
Molar mass 157.104 g·mol−1
Pharmacology
J05AX27 (WHO)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

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

 

ANTHONY MELVIN CRASTO

Want to know everything on vir series

click

http://drugsynthesisint.blogspot.in/p/vir-series-hep-c-virus-22.html

AND

http://medcheminternational.blogspot.in/p/vir-series-hep-c-virus.html

 

wdt-20

WORLD DRUG TRACKER

one time

$10.00

PALINAVIR


PALINAVIR, BILA-2011-BS

UNII-632S1WU9Z2, 154612-39-2, n-[(1s)-1-[[(1s,2r)-1-benzyl-3-[(2s,4r)-2-(tert-butylcarbamoyl)-4-(4-pyridylmethoxy)piperidino]-2-hydroxypropyl]carbamoyl]-2-methylpropyl]quinaldamide,
N-[(2S)-1-[[(2S,3R)-4-[(2S,4R)-2-(tert-butylcarbamoyl)-4-(pyridin-4-ylmethoxy)piperidin-1-yl]-3-hydroxy-1-phenylbutan-2-yl]amino]-3-methyl-1-oxobutan-2-yl]quinoline-2-carboxamide
Molecular Formula:C41H52N6O5
Molecular Weight:708.88878 g/mol
Patent Submitted Granted
Substituted pipecolinic acid derivatives as HIV protease inhibitors [US5614533] 1997-03-25
Substituted pipecolinic acid derivatives as HIV protease inhibitors. [EP0560268] 1993-09-15 1995-01-04

……………………….

PATENT

http://www.google.com/patents/WO2013105118A1?cl=en

Scheme 5: Synthesis of Palinavir (6):

Figure imgf000018_0002

The organic solvent mentioned according to the invention is selected from the group consisting of organic solvents, wherein the organic solvents are polar aprotic such as DCM, THF, Ethyl acetate, acetone, DMF, acetonitrile, DMSO ; polar protic solvents such as lower alcohol particularly (C1-C6) alkyl alcohol, water, acetic acid ; non-polar solvents such as hexane, benzene, toluene, chloroform, pet. ether, 1,4-dioxane, heptane either alone or mixtures thereof . Additionally the purification or separation of crude product can be accomplished by known techniques viz. extraction, column chromatography in a suitable organic solvent with the aid of instruments such as TLC, HPLC, GC, mass spectroscopy, or distillation, crystallization, derivatization.

Want to know everything on vir series

click

http://drugsynthesisint.blogspot.in/p/vir-series-hep-c-virus-22.html

AND

http://medcheminternational.blogspot.in/p/vir-series-hep-c-virus.html

………………………….

J Org Chem 1997,62(11),3440

The reaction of tert-butoxycarbonyl-L-phenylalanine (I) with isobutyl chloroformate in THF gives the expected mixed anhydride which is treated with diazomethane and HCl yielding the corresponding chloromethyl ketone (II). The reduction of (II) with NaBH4 in THF affords the (S)-chlorohydrin (IV), which is treated with KOH in ethanol to obtain the chiral epoxide (V)(1,2). Ring opening of (V) with (?(cis)-N-tert-butyl-4-(4-pyridylmethoxy)piperidine-2-carboxamide (VI) by a treatment with LiCl in refluxing ethanol gives a mixture of diastereomers that is separated by chromatography giving the pure isomer (VII). The reaction of (VII) with tert-butoxycarbonyl-L-valine (VIII) by treatment first with trifluoroacetic acid (TFA), and condesation by means of BOP ((benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate) and NMM (N-methylmorpholine) affords the expected condensation product (IX). Finally, this compound is condensed with quinoline-2-carboxylic acid (X) by means of BOP and NMM as before. 2) The piperidine (VI) has been obtained by condensation of (?(cis)-N-(tert-butoxycarbonyl)-4-hydroxypiperidine-2-carboxamide (XI) with 4-(chloromethyl)pyridine (XII) by means of NaH in DMS, followed by hydrolysis with HCl.

Palinavir can also be obtained as follows: The controlled oxidation of 2(S)-(dibenzylamino)-3-phenyl-1-propanol (XIII) with pyridine-SO3 complex in DMSO gives the corresponding aldehyde (XIV), which is condensed with bromochloromethane (XV) by means of Li in THF followed by hydrolysis with HCl yielding regioselectively the 1-chloro-2-butanol (XVI). The debenzylation of (XVI) by hydrogenation over Pd/C affords the free amine (XVII), which is treated with tert-butoxycarbonyl anhydride/triethylamine and dehydrochlorinated with KOH in methanol to give the desired chiral epoxide (V).

The chiral piperidine (2S,4R)(VI) has been obtained as follows: The cyclization of 3-buten-1-ol (XXII) with (S)-1-phenylethylamine (XXIII) and glyoxylic acid (XXIV) by means of tosyl chloride in THF gives a mixture of the (2S,4R) and (2R,4S) lactones (XXV), which is resolved by fractional crystallyzation of their salts with the chiral camphorsulfonic acid (XXVI), followed by elimination of the acid with ammonia to afford (2S,4R)(XXVII). The reaction of lactone (XXVII) with isopropylmagnesium chloride and tert-butylamine in THF gives (2S,4R)-N-tert-butyl-4-hydroxy-1-(1(S)-phenylethyl)piperidine-2-carboxamide (XXVIII), which is debenzylated by hydrogenation and protected with tert-butoxycarbonyl anhydride yielding (2S,4R)-N-(tert-butoxycarbonyl)-4-hydroxypiperidine-2-carboxamide (2S,4R)(XI), which is finally condensed with 4-(chloromethyl)pyridine (XII) as before to obtain the chiral piperidine (2S,4R)(VI), already reported.

The condendsation of epoxide (V) with (2S,4R)(VI) by means of basic alumina in THF, followed by elimination of the protecting group with HCl and NaOH yields directly the condensation product (XVIII) as a pure diastereomer and with a free amino group. Finally, this compound is condensed with N-(2-quinolylcarbonyl)-L-valine (XIX) through its activation compound with isobutyl chloroformate (the 4(S)-isopropyl-2-(2-quinolyl)oxazol-5(4H)-one (XX)). The N-acyl-L-valine (XIX) has been obtained by acylation of L-valine (XXI) with quinoline-2-carboxylic acid (X) through its acyl chloride obtained with SOCl2.

………………………..

Palinavir is an inhibitor with five chiral centers. It contains the amino acid valine and pipecolinin acid. The previous way to create this drug faced three major obstacles. First, the reaction from 2 to 3 used diazomethane. Therefore, is is difficult, if not impossible, to produce large quantities. Secondly, the steps included in going from 4 to 5 gave way to racemers which is very inefficient. Finally, chromatography is needed at two separate times.

Four issues were addresses in route to product 1. First, because of the number of chiral centers, stereochemical control was a concern. high chemical yields were a second concern. Also, multi step procedures were advantageous to cut down on purification steps. Finally, the synthesis tried to restrict the use of hazardous reagents. The following retrosynthesis reaction was conceived and three target molecules were identified as seen in figure 1.

Molecule 3 uses a diaseteroselective addition of in situ (chloromethyl)lithium to N,N-dibenzylphenylalaninol and is derived from a four step process.

Recrystallization of 13 is required. Molecule 14 was not reached because it posed a problem later in the reaction. The N-benzyl protection group could not be removed to react with 9.

8 is a derivative of naturally occurring pipocolic acid, 16, named 3-buten-1-ol. Selective crystallization of diastereomeric salts can lead to 17a, but a more efficient way is by having a 60:40 mixture of lactones 17a,b. This leads to 18a,b using a Brodroux process. Crystallization of 18a,b lead to a poor overall yield. Instead, 18a,b undergoes salt crystallization with (-)-camphorsulfonic acid. Finally, 18a underwent hydrolysis and then addition of di-tert butyl dicarbonate leads to 8.

8 was then transformed to 5 in a three step process.

8 was added to NaOH and alkylated with 4-picolyl chloride. The protecting group was lost with the addition of acid. 

Derivation of 9 was started by a simple substitution of 19, quinoline-2-carboxylic acid, to 20, an acid chloride, with the help of thionyl chloride. Acylation of amino acid L-valine to 20 was accomplished by a biphasic system.

In the original synthesis of palinavir, a 2:1 mixture of 3 to 5 was needed to produce only ~35% of 6 and flash chromatography was needed. On a large scale without chromatography, 6 was produced with a 85% yield, but 21 was also produced. To keep the production of 21 to a minimum, the reaction was performed in a solution that was degassed. This insured that the pyridine ring would not react in the presence of air. With this precaution, only 1-2% of the yield was 21. A washing of the solution with 1 M KH2PO4 removed and left over 5. Deprotection was achieved with the addition of concentrated HCl and followed by adding NaOH. The product of 10 was a “viscous syrup”. 22 was 1-1.5% of the product and was not removed before the addition of 9 to form 80-85% palinavir.

Coupling of 10 and 9 is the final step in the synthesis , although there are still some purification steps left.

Two recrystallizations were required for the final 99.6% purity.

………………………..

J. Org. Chem., 1997, 62 (11), pp 3440–3448
DOI: 10.1021/jo9702655
Abstract Image

Palinavir is a potent peptidomimetic-based HIV protease inhibitor. We have developed a highly convergent and stereoselective synthesis which is amenable to the preparation of multikilogram quantities of this compound. The synthetic sequence proceeds in 24 distinct chemical steps (with several integrated, multistep operations) from commercially available starting materials. No chromatographies are required throughout the process, and the final product is purified by crystallization of its dihydrochloride salt to >99% homogeneity.

crude palinavir (1) as a thick brown oil (yield not determined). HPLC analysis (Supelcosil LZ-ABZ, 10−50% 1% TFA in MeCN/1% TFA in 25 min, 1 mL/min flow rate): 1, tR 17.80 min (84.1%); 24, tR 18.47 min (2.0%); 25, tR 19.97 min (1.45%).

palinavir dihydrochloride (1750 g, 51% yield) containing 0.25% w/w isopropanol (by 1H NMR):

mp 175−185 °C.

[α]25D −13.0° (c 1, MeOH). [α]25Hg365 +44.9° (c 1, MeOH).

IR (KBr) ν 3700−2300, 1660, 1555, 1520 cm-1.

1H NMR (DMSO-d6) δ 10.00 (broad s, 1H), 8.88 (d, J = 6.3 Hz, 2H), 8.61 (d, J = 8.4 Hz, 1H), 8.60 (s, 1H), 8.51 (d, J = 9.6 Hz, 1H), 8.35 (d, J = 8.7 Hz, 1H), 8.20 (d, J = 8.4 Hz, 1H), 8.16 (d, J = 8.7 Hz, 1H), 8.11 (d, J = 8.1 Hz, 1H), 7.94 (d, J = 6.0 Hz, 2H), 7.89 (t, J = 7.6 Hz, 1H), 7.74 (t, J = 7.5 Hz, 1H), 7.19 (d, J = 7.2 Hz, 2H), 7.08 (t, J = 7.5 Hz, 2H), 6.91 (t, J = 7.3 Hz, 1H), 4.86 (AB quartet, 2H), 4.37 (broad t, J = 7.8 Hz, 1H), 4.21 (d, J = 11.4 Hz, 1H), 4.11 (broad m, 1H), 3.96 (broad m, 1H), 3.80−3.65 (m, 2H), 3.26 (t, J = 7.4 Hz, 1H), 3.15−3.01 (m, 2H), 2.94 (broad d, J = 12.0 Hz, 1H), 2.62 (dd, J = 13.6, 10.6 Hz, 1H), 2.56 ((broad d, J = 12.0 Hz, 1H), 2.20−2.05 (m, 2H), 1.86 (m, 1H), 1.69 (q, J = 11.7 Hz, 1H), 1.31 (s, 9H), 0.81 (d, J = 6.3 Hz, 3H), 0.80 (d, J = 6.6 Hz, 3H).

13C NMR (DMSO-d6) δ 170.4, 166.4, 163.3, 158.3, 149.5, 145.9, 141.9, 138.6, 138.2, 130.7, 129.3, 129.1, 129.0, 128.3, 128.2, 128.0, 125.9, 124.1, 118.6, 72.3, 68.8, 67.2, 64.8, 58.0, 57.8, 54.4, 51.3, 51.1, 35.4, 34.1, 31.1, 28.2, 19.5, 17.9.

FAB-MS m/z 709 (MH+ of free base). Anal. Calcd for C41H54Cl2N6O5 (corrected for 8% water content as determined by Karl Fisher analysis and 0.25% w/w isopropanol as determined by 1H NMR):  C, 58.31; H, 7.29; N, 9.93. Found:  C, 57.76; H, 7.25; N, 9.89. Titration of HCl content using NaOH:  2.09 ± 0.03 mol HCl. HPLC homogeneity (Supelcosil LC-ABZ, 10−50% 1% TFA in MeCN/1% TFA in 25 min, 1 mL/min flow rate):  palinavir dihydrochloride, tR 18.24 min (99.51%); 25 tR 20.39 min (0.33%). HPLC homogeneity (Nova-Pak C8, 20−80% MeCN/50 mM NaH2PO4 in 25 min, 1 mL/min flow rate):  palinavir dihydrochloride, tR 15.52 min (99.67%); 25 tR 13.52 min (0.33%).

PURE palinavir (1) as a white amorphous powder (1902 g, 84% yield):

mp 100−107 °C. [α]25D −11.5° (c 1, MeOH).

IR (KBr) ν 3700−3100, 1660, 1520, 1495 cm-1.

1H NMR (CDCl3) δ 8.54 (d, J = 5.7 Hz, 2H), 8.48 (d, J = 8.6 Hz, 1H), 8.31 (d, J = 8.6 Hz, 1H, part of AB), 8.22 (d, J = 8.3 Hz, 1H, part of AB), 8.13 (d, J = 8.3 Hz, 1H), 7.90 (d, J = 8.0 Hz, 1H), 7.80 (t, J = 7.6 Hz, 1H), 7.65 (t, J = 7.6 Hz, 1H), 7.25 (d, J = 5.4 Hz, 2H), 7.13 (d, J = 7.3 Hz, 2H), 7.07 (t, J = 7.5 Hz, 1H), 6.92 (t, J = 7.3 Hz, 1H), 6.59 (d, J = 8.3 Hz, 1H), 6.57 (s, 1H), 4.61 (d, J = 13.4 Hz, 1H, part of AB), 4.51 (d, J = 13.4 Hz, 1H, part of AB), 4.32 (dd, J = 8.6, 6.4 Hz, 1H), 4.22 (m, 1H), 3.97 (m, 1), 3.47−3.33 (m, 2H), 2.94 (dd, J = 14.3, 4.1 Hz, 1H), 2.89 (d, J= 8.6 Hz, 1H), 2.79−2.72 (m, 1H), 2.77 (dd, J = 14.3, 10.8 Hz, 1H), 2.43 (dd, J = 13.4, 8.3 Hz, 1H), 2.40−2.25 (m, 3H), 1.95 (broad d, J = 12.4 Hz, 1H), 1.65 (q J = 11.8 Hz, 2H), 1.32 (s, 9H), 0.95 (d, J = 7.0 Hz, 3H), 0.83 (d, J = 6.7 Hz, 3H).

13C NMR (CDCl3) δ 171.6, 171.2, 165.0, 149.8, 148.8, 147.9, 146.5, 137.6, 137.5, 130.3, 129.9, 129.5, 129.4, 129.0, 128.8, 128.5, 128.2, 127.7, 126.4, 121.7, 118.8, 75.0, 71.9, 68.1, 66.7, 59.4, 56.9, 54.6, 50.9, 50.2, 34.8, 33.3, 29.8, 29.7, 28.7, 19.6, 17.5.

FAB-MS m/z 709 (MH+). Anal. Calcd for C41H52N6O5(corrected for 0.7% water content as determined by Karl Fisher analysis):  C, 68.98; H, 7.42; N, 11.77. Found:  C, 68.71; H, 7.47; N, 11.71. HPLC homogeneity (Supelcosil LC-ABZ, 10−50% 1% TFA in MeCN/1% TFA in 25 min, 1 mL/min flow rate):  palinavir (1), tR 17.83 min (99.59%); 25 tR20.00 min (0.41%). HPLC homogeneity (Nova-Pak C8, 10−80% MeCN/50 mM NaH2PO4 in 25 min, 1 mL/min flow rate):  palinavir (1), tR 17.37 min (99.51%); 25 tR 15.87 min (0.49%).

Reference
1 * ARUN K. GHOSH ET AL: “The Development of Cyclic Sulfolanes as Novel and High-Affinity P2 Ligands for HIV-1 Protease Inhibitors“, JOURNAL OF MEDICINAL CHEMISTRY, vol. 37, no. 8, 1 April 1994 (1994-04-01), pages 1177-1188, XP055057710, ISSN: 0022-2623, DOI: 10.1021/jm00034a016
2 * KAY BRICKMANN ET AL: “Synthesis of Conformationally Restricted Mimetics of [gamma]-Turns and Incorporation into Desmopressin, an Analogue of the Peptide Hormone Vasopressin“, CHEMISTRY – A EUROPEAN JOURNAL, vol. 5, no. 8, 2 August 1999 (1999-08-02), pages 2241-2253, XP055057517, ISSN: 0947-6539, DOI: 10.1002/(SICI)1521-3765(19990802)5:8<2241: :AID-CHEM2241>3.0.CO;2-L
3 * KIRAN I N C ET AL: “A concise enantioselective synthesis of (+)-goniodiol and (+)-8-methoxygoniodiol via Co-catalyzed HKR of anti-(2SR, 3RS)-3-methoxy-3-phenyl-1, 2-epoxypropane“, TETRAHEDRON LETTERS, ELSEVIER, AMSTERDAM, NL, vol. 52, no. 3, 19 January 2011 (2011-01-19), pages 438-440, XP027558447, ISSN: 0040-4039 [retrieved on 2010-12-14]
4 * M. TOKUNAGA: “Asymmetric Catalysis with Water: Efficient Kinetic Resolution of Terminal Epoxides by Means of Catalytic Hydrolysis“, SCIENCE, vol. 277, no. 5328, 15 August 1997 (1997-08-15), pages 936-938, XP055057541, ISSN: 0036-8075, DOI: 10.1126/science.277.5328.936
5 * PARKES K E B ET AL: “STUDIES TOWARD THE LARGE-SCALE SYNTHESIS OF THE HIV PROTEINASE INHIBITOR RO 31-8959“, JOURNAL OF ORGANIC CHEMISTRY, ACS, US, vol. 59, no. 13/16, 1 January 1994 (1994-01-01), pages 3656-3664, XP002011975, ISSN: 0022-3263, DOI: 10.1021/JO00092A026
6 * R. SANTHOSH REDDY ET AL: “Co(iii)(salen)-catalyzed HKR of two stereocentered alkoxy- and azido epoxides: a concise enantioselective synthesis of (S,S)-reboxetine and (+)-epi-cytoxazone“, CHEMICAL COMMUNICATIONS, vol. 46, no. 27, 1 January 2010 (2010-01-01), page 5012, XP055057537, ISSN: 1359-7345, DOI: 10.1039/c0cc00650e
7 * SHINJI NAGUMO ET AL: “Intramolecular Friedel-Crafts type reaction of vinyloxiranes linked to an ester group“, TETRAHEDRON, vol. 65, no. 47, 1 November 2009 (2009-11-01), pages 9884-9896, XP055057655, ISSN: 0040-4020, DOI: 10.1016/j.tet.2009.09.037
8 * SUNITA K. GADAKH ET AL: “Enantioselective synthesis of HIV protease inhibitor amprenavir via Co-catalyzed HKR of 2-(1-azido-2-phenylethyl)oxirane“, TETRAHEDRON: ASYMMETRY, vol. 23, no. 11-12, 1 June 2012 (2012-06-01), pages 898-903, XP055057475, ISSN: 0957-4166, DOI: 10.1016/j.tetasy.2012.06.003

Want to know everything on vir series

click

http://drugsynthesisint.blogspot.in/p/vir-series-hep-c-virus-22.html

AND

http://medcheminternational.blogspot.in/p/vir-series-hep-c-virus.html