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Showing posts with label HIV-1 integrase inhibitor. Show all posts
Showing posts with label HIV-1 integrase inhibitor. Show all posts

Monday, 28 December 2015

GS 9883, Bictegravir an HIV-1 integrase inhibitor

UNII-8GB79LOJ07.png
GS 9883, bictegravir
CAS 1611493-60-7
PHASE 3
HIV-1 integrase inhibitor
(2R,5S,13aR)-8-hydroxy-7,9-dioxo-N-[(2,4,6-trifluorophenyl)methyl]-2,3,4,5,7,9,13,13a-octahydro-2,5-methanopyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazepine-10-carboxamide
2,5-Methanopyrido(1′,2′:4,5)pyrazino(2,1-b)(1,3)oxazepine-10-carboxamide, 2,3,4,5,7,9,13,13a-octahydro-8-hydroxy-7,9-dioxo-N-((2,4,6-trifluorophenyl)methyl)-, (2R,5S,13aR)-

2,5-Methanopyrido(1′,2′:4,5)pyrazino(2,1-b)(1,3)oxazepine-10-carboxamide, 2,3,4,5,7,9,13,13a-octahydro-8-hydroxy-7,9-dioxo-N-((2,4,6-trifluorophenyl)methyl)-, (2R,5S,13aR)-

(2R,5S,13aR)-8-hydroxy-7,9-dioxo-N-(2,4,6-trifluorobenzyl)-2,3,4,5,7,9,13,13a-octahydro-2,5-methanopyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazepine-10-carboxamide
(2 ,5S,13aI )-8-hydroxy-7,9-dioxo-N-(2,4,6-trifluoroheoctahydro-2,5-methanopyrido[ 1 ‘,2’:4,5]pyrazino[2, 1 -b][ 1 ,3]oxazepine- 10-carboxamide
MF  C21H18F3N3O5,
 MW 449.37993 g/mol
 UNII-8GB79LOJ07; 8GB79LOJ07



2D chemical structure of 1611493-60-7
BICTEGRAVIR

  • 16 Nov 2015 Phase-III clinical trials in HIV-1 infections (Combination therapy, Treatment-naive) in USA (PO) (Gilead Pipeline, November 2015)
  • 01 Jul 2015 Gilead Sciences completes a phase I trial in HIV-1 infections in USA and New Zealand (NCT02400307)
  • 01 Apr 2015 Phase-I clinical trials in HIV-1 infections (In volunteers) in New Zealand (PO) (NCT02400307)
Human immunodeficiency virus infection and related diseases are a major public health problem worldwide. Human immunodeficiency virus type 1 (HIV-1) encodes three enzymes which are required for viral replication: reverse transcriptase, protease, and integrase. Although drugs targeting reverse transcriptase and protease are in wide use and have shown effectiveness, particularly when employed in combination, toxicity and development of resistant strains have limited their usefulness (Palella, et al. N. Engl. J Med. (1998) 338:853-860; Richman, D. D. Nature (2001) 410:995-1001). Accordingly, there is a need for new agents that inhibit the replication of HIV and that minimize PXR activation when co-administered with other drugs.
Certain polycyclic carbamoylpyridone compounds have been found to have antiviral activity, as disclosed in PCT/US2013/076367. Accordingly, there is a need for synthetic routes for such compounds.

 

SYNTHESIS COMING……..


PATENTS
WO2014100323
xample 42
Preparation of Compound 42
(2 ,5S,13aI )-8-hydroxy-7,9-dioxo-N-(2,4,6-trifluorohe
octahydro-2,5-methanopyrido[ 1 ‘,2’:4,5]pyrazino[2, 1 -b][ 1 ,3]oxazepine- 10-carboxamide

42

Step 1
l-(2,2-dimethoxyethyl)-5-methoxy-6-(methoxycarbonyl)-4-oxo-l ,4-dihydropyridine-3-carboxylic acid (3.15 g, 10 mmol) in acetonitrile (36 mL) and acetic acid (4 mL) was treated with methanesuffhnic acid (0.195 mL, 3 mmol) and placed in a 75 deg C bath. The reaction mixture was stirred for 7 h, cooled and stored at -10 °C for 3 days and reheated to 75 °C for an additional 2 h. This material was cooled and carried on crude to the next step.
Step 2
Crude reaction mixture from step 1 (20 mL, 4.9 mmol) was transferred to a flask containing (lR,3S)-3-aminocyclopentanol (0.809 g, 8 mmol). The mixture was diluted with acetonitrile (16.8 mL), treated with potassium carbonate (0.553 g, 4 mmol) and heated to 85 °C. After 2 h, the reaction mixture was cooled to ambient temperature and stirred overnight. 0.2M HQ (50 mL) was added, and the clear yellow solution was extracted with dichloromethane (2×150 mL). The combined organic layers were dried over sodium sulfate, filtered and concentrated to 1.49 g of a light orange solid. Recrystallization from dichloimethane:hexanes afforded the desired intermediate 42 A: LC S-ESI (m/z): [M+H]+ calculated for Ci5Hi7N206: 321.1 1 ; found: 321.3.
Step 3
Intermediate 42-A (0.225 g, 0.702 mmol) and (2,4,6-trifluorophenyl)methanamine (0.125 g, 0.773 mmol) were suspended in acetonitrile (4 mL) and treated with N,N-diisopropylethylamine (DIPEA) (0.183 mmol, 1.05 mmol). To this suspension was added (dimethyiammo)- V,A/-dimethyi(3H-[l ,2,3]triazolo[4,5-&]pyridm~3-yiox.y)methammimum hexafluorophosphate (HATU, 0.294 g, 0.774 mmol). After 1.5 hours, the crude reaction mixture was taken on to the next step. LfJMS-ESlT (m/z): [M+H calculated for (\ ,l l.,, i \\:0< : 464.14; found: 464.2.
Step 4
To the crude reaction mixture of the previous step was added MgBr2
(0.258 g, 1.40 mmol). The reaction mixture was stirred at 50 °C for 10 minutes, acidified with 10% aqueous HC1, and extract twice with dichloromethane. The combined organic phases were dried over MgS04, filtered, concentrated, and purified by silica gel chromatography (EtOH/dichlormethane) followed by HPLC (ACN H2O with 0.1 % TFA modifier) to afford compound 42: 1H~ M (400 MHz, DMSO-</6) δ 12.43 (s, 1H), 10.34 (t, J = 5.7 Hz, IH), 8.42 (s, 1H), 7.19 (t, J = 8.7 Hz, 2H), 5.43 (dd, ./’ 9.5, 4.1 Hz, I H), 5.08 (s, i l l ). 4.66 (dd, ./ 12.9, 4.0 Hz, IH), 4.59 (s, 1 1 1 ). 4.56 4.45 (m, 2H), 4.01 (dd, J = 12.7, 9.7 Hz, IH), 1.93 (s, 4H), 1.83 (d, J —— 12.0 Hz, I H),
1.56 (dt, J = 12.0, 3.4 Hz, I H). LCMS-ESI+ (m/z): [M+H]+ calculated for { · Ί ί ] ΝΓ :Χ.¾ϋ : 450.13; found: 450.2.


PATENT
WO2015177537
https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015177537&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCTDescription


PATENT
WO2015196116
https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015196116&redirectedID=true


PATENT
WO2015196137
https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2015196137&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCTDescription


PATENT
http://www.google.com/patents/US20140221356
Example 42 Preparation of Compound 42 (2R,5S,13aR)-8-hydroxy-7,9-dioxo-N-(2,4,6-trifluorobenzyl)-2,3,4,5,7,9,13,13a-octahydro-2,5-methanopyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazepine-10-carboxamide
Step 1
  • 1-(2,2-dimethoxyethyl)-5-methoxy-6-(methoxycarbonyl)-4-oxo-1,4-dihydropyridine-3-carboxylic acid (3.15 g, 10 mmol) in acetonitrile (36 mL) and acetic acid (4 mL) was treated with methanesulfonic acid (0.195 mL, 3 mmol) and placed in a 75 deg C. bath. The reaction mixture was stirred for 7 h, cooled and stored at −10° C. for 3 days and reheated to 75° C. for an additional 2 h. This material was cooled and carried on crude to the next step.
Step 2
  • Crude reaction mixture from step 1 (20 mL, 4.9 mmol) was transferred to a flask containing (1R,3S)-3-aminocyclopentanol (0.809 g, 8 mmol). The mixture was diluted with acetonitrile (16.8 mL), treated with potassium carbonate (0.553 g, 4 mmol) and heated to 85° C. After 2 h, the reaction mixture was cooled to ambient temperature and stirred overnight. 0.2M HCl (50 mL) was added, and the clear yellow solution was extracted with dichloromethane (2×150 mL). The combined organic layers were dried over sodium sulfate, filtered and concentrated to 1.49 g of a light orange solid. Recrystallization from dichlormethane:hexanes afforded the desired intermediate 42A: LCMS-ESI+ (m/z): [M+H]+ calculated for C15H17N2O6: 321.11; found: 321.3.
Step 3
  • Intermediate 42-A (0.225 g, 0.702 mmol) and (2,4,6-trifluorophenyl)methanamine (0.125 g, 0.773 mmol) were suspended in acetonitrile (4 mL) and treated with N,N-diisopropylethylamine (DIPEA) (0.183 mmol, 1.05 mmol). To this suspension was added (dimethylamino)-N,N-dimethyl(3H-[1,2,3]triazolo[4,5-b]pyridin-3-yloxy)methaniminium hexafluorophosphate (HATU, 0.294 g, 0.774 mmol). After 1.5 hours, the crude reaction mixture was taken on to the next step. LCMS-ESI+ (m/z): [M+H]+ calculated for C22H21F3N3O5: 464.14; found: 464.2.
Step 4
  • To the crude reaction mixture of the previous step was added MgBr2 (0.258 g, 1.40 mmol). The reaction mixture was stirred at 50° C. for 10 minutes, acidified with 10% aqueous HCl, and extract twice with dichloromethane. The combined organic phases were dried over MgSO4, filtered, concentrated, and purified by silica gel chromatography (EtOH/dichlormethane) followed by HPLC (ACN/H2O with 0.1% TFA modifier) to afford compound 42: 1H-NMR (400 MHz, DMSO-d6) δ 12.43 (s, 1H), 10.34 (t, J=5.7 Hz, 1H), 8.42 (s, 1H), 7.19 (t, J=8.7 Hz, 2H), 5.43 (dd, J=9.5, 4.1 Hz, 1H), 5.08 (s, 1H), 4.66 (dd, J=12.9, 4.0 Hz, 1H), 4.59 (s, 1H), 4.56-4.45 (m, 2H), 4.01 (dd, J=12.7, 9.7 Hz, 1H), 1.93 (s, 4H), 1.83 (d, J=12.0 Hz, 1H), 1.56 (dt, J=12.0, 3.4 Hz, 1H). LCMS-ESI+ (m/z): [M+H]+ calculated for C21H19F3N3O5: 450.13; found: 450.2.


PATENT

WO-2015195656

General Scheme I:

General Scheme II:



General Scheme II
General Scheme III:


General Scheme III
General Scheme IV:


G-1

General Scheme V:

II

EXAMPLES
In order for this invention to be more fully understood, the following examples are set forth. These examples are for the purpose of illustrating embodiments, and are not to be construed as limiting the scope of this disclosure in any way. The reactants used in the examples below may be obtained either as described herein, or if not described herein, are themselves either commercially available or may be prepared from commercially available materials by methods known in the art.
In one embodiment, a multi-step synthetic method for preparing a compound of Formula I is provided, as set forth below. In certain embodiments, each of the individual steps of the Schemes set forth below is provided. Examples and any combination of two or more successive steps of the below Examples are provided.
A. Acylation and amidation of Meldrum ‘s acid to form C-la:

[0520] In a reaction vessel, Meldrum’s acid (101 g, 1.0 equivalent) and 4-dimethylaminopyridine (1.8 g, 0.2 equivalents) were combined with acetonitrile (300 mL). The resulting solution was treated with methoxyacetic acid (6.2 mL, 1.2 equivalents). Triethylamine (19.4 mL, 2.0 equivalents) was added slowly to the resulting solution, followed by pivaloyl chloride (9.4 mL, 1.1 equivalents). The reaction was then heated to about 45 to about 50 °C and aged until consumption of Meldrum’s acid was deemed complete.
A separate reaction vessel was charged with acetonitrile (50 mL) and J-la (13.4 g, 1.2 equivalents). The resulting solution was treated with trifluoroacetic acid (8.0 mL, 1.5 equivalents), and then this acidic solution was added to the acylation reaction in progress at about 45 to about 50 °C.
The reaction was allowed to age for at least 18 hours at about 45 to about 50 °C, after which time the solvent was removed under reduced pressure. The crude residue was dissolved in ethyl acetate (150 mL), and the organic layer was washed with water. The combined aqueous layers were extracted with ethyl acetate. The combined organic layers were washed with saturated sodium bicarbonate solution, and the combined bicarbonate washes were back extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The resulting crude material was purified twice via silica gel chromatography to yield C-la.
lH NMR (400 MHz, CDC13): δ 7.12 (br, 1H), 6.66 (app t, J= 8.1 Hz, 2H), 4.50 (app d, J= 5.7 Hz, 2H), 4.08 (s, 2H), 3.44 (s, 2H), 3.40 (s, 3H). 13C NMR (100 MHz, CDC13): δ 203.96, 164.90, 162.37 (ddd, J= 250.0, 15.7, 15.7 Hz), 161.71 (ddd, J = 250.3, 14.9, 10.9 Hz), 110.05 (ddd, J= 19.7, 19.7, 4.7 Hz), 100.42 (m), 77.58, 59.41, 45.71, 31.17 (t, J= 3.5 Hz). LCMS, Calculated: 275.23, Found: 275.97 (M).
I l l
B. Alkylation of C-la to form E-la:

A solution of C-la (248 mg, 1.0 equivalent) and 2-methyl tetrahydrofuran (1.3 niL) was treated with N,N-dimethylformamide dimethylacetal (0.1 mL, 1.1 equivalent) and stirred at room temperature overnight (~14 hours). The reaction was treated with aminoacetaldehyde dimethyl acetal (0.1 mL, 1.0 equivalents), and was allowed to age for about 2 hours, and then was quenched via the addition of 2 Ν HC1
(1.5 mL).
The reaction was diluted via the addition of ethyl acetate, and phases were separated. The aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The crude residue was purified via silica gel chromatography to yield E-la.
1H NMR (400 MHz, CDC13): δ 10.85 (s, 1H), 9.86 (s, 1H), 8.02 (d, J= 13.1 Hz, 1H), 6.65 (dd, J= 8.7, 7.7 Hz, 2H), 4.53 (d, J= 3.9 Hz, 2H), 4.40 (t, J= 5.1 Hz, 1H), 4.18 (s, 2H), 3.42 (s, 6H), 3.39 (m, 2H), 3.37 (s, 3H). 13C MR (100 MHz, CDC13): δ 193.30, 169.15, 162.10 (ddd, J= 248.9, 15.5, 15.5 Hz), 161.7 (ddd, J =
250.0, 14.9, 1 1.1 Hz), 161.66, 1 11.08 (ddd J= 19.9, 19.9, 4.7 Hz) 103.12, 100.29 (ddd, J= 28.1, 17.7, 2.3 Hz), 76.30, 58.83, 54.98, 53.53, 51.57, 29.89 (t, J= 3.3 Hz). LCMS, Calculated: 390.36, Found: 390.92 (M).
c. Cyclization of E-la to form F-la:

E-1a F-1a
] E-la (0.2 g, 1.0 equivalent), dimethyl oxalate (0.1 g, 2.5 equivalents) and methanol (1.5 mL) were combined and cooled to about 0 to about 5 °C. Sodium methoxide (0.2 mL, 30% solution in methanol, 1.75 equivalents) was introduced to the reaction slowly while keeping the internal temperature of the reaction below about 10 °C throughout the addition. After the addition was completed the reaction was heated to about 40 to about 50 °C for at least 18 hours.
After this time had elapsed, the reaction was diluted with 2 N HC1 (1.5 mL) and ethyl acetate (2 mL). The phases were separated, and the aqueous phase was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over magnesium sulfate, filtered, and solvent was removed under reduced pressure. The resulting crude oil was purified via silica gel chromatography to afford F-la.
lR NMR (400 MHz, CDC13): δ 10.28 (t, J= 5.5 Hz, 1H), 8.38 (s, 1H), 6.66 – 6.53 (m, 2H), 4.58 (d, J= 5.6 Hz, 2H), 4.43 (t, J= 4.7 Hz, 1H), 4.00 (d, J= 4.7 Hz, 2H), 3.92 (s, 3H), 3.88 (s, 3H), 3.32 (s, 6H). 13C NMR (100 MHz, CDC13): δ 173.08, 163.81, 162.17, 162.14 (ddd, J= 249.2, 15.6, 15.6 Hz), 161.72 (ddd, J= 250.5, 15.0, 10.9 Hz), 149.37, 144.64, 134.98, 119.21, 1 10.53 (ddd, J= 19.8, 4.7, 4.7 Hz), 102.70, 100.22 (m), 60.68, 56.75, 55.61, 53.35, 30.64. LCMS, Calculated: 458.39, Found: 459.15 (M+H).
D. Alkylation and cyclization of C-la to form F-la:
1 . DMFDMA

C-1a NaOMe, MeOH, 40 °C F-1a
To a reaction vessel were added C-la (245 mg, 1.0 equivalent) and N,N-dimethylformamide dimethylacetal (0.5 mL, 4.3 equivalent). The reaction mixture was agitated for approximately 30 minutes. The reaction was then treated with 2-methyl tetrahydrofuran (2.0 mL) and aminoacetaldehyde dimethyl acetal (0.1 mL, 1.0 equivalent). The reaction was allowed to age for several hours and then solvent was removed under reduced pressure.
The resulting material was dissolved in methanol and dimethyl oxalate was added (0.3 g, 2.5 equivalents). The reaction mixture was cooled to about 0 to about 5 °C, and then sodium methoxide (0.4 mL, 30% solution in methanol, 1.75 equivalents) was introduced to the reaction slowly. After the addition was completed the reaction was heated to about 40 to about 50 °C.
After this time had elapsed, the reaction was cooled to room temperature and quenched via the addition of 2 Ν HC1 (1.5 mL). The reaction was then diluted with ethyl acetate, and the resulting phases were separated. The aqueous layer was extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The crude residue was purified via silica gel chromatography to yield F-la.
lR NMR (400 MHz, CDC13): δ 10.28 (t, J= 5.5 Hz, 1H), 8.38 (s, 1H), 6.66 – 6.53 (m, 2H), 4.58 (d, J= 5.6 Hz, 2H), 4.43 (t, J= 4.7 Hz, 1H), 4.00 (d, J= 4.7 Hz, 2H), 3.92 (s, 3H), 3.88 (s, 3H), 3.32 (s, 6H). 13C NMR (100 MHz, CDC13): δ 173.08, 163.81, 162.17, 162.14 (ddd, J= 249.2, 15.6, 15.6 Hz), 161.72 (ddd, J= 250.5, 15.0, 10.9 Hz), 149.37, 144.64, 134.98, 119.21, 1 10.53 (ddd, J= 19.8, 4.7, 4.7 Hz), 102.70, 100.22 (m), 60.68, 56.75, 55.61, 53.35, 30.64. LCMS, Calculated: 458.39, Found: 459.15 (M+H).
E. Condensation of F-la with N-la to form G-la:

K2C03, MeCN, 75 °C
To a reaction vessel were added F-la (202 mg, 1.0 equivalent) and acetonitrile (1.4 mL). The resulting solution was treated with glacial acetic acid (0.2 mL, 6.0 equivalents) and methane sulfonic acid (0.01 mL, 0.3 equivalents). The reaction was then heated to about 70 to about 75 °C.
After 3 hours, a solid mixture of N-la (0.128g, 1.5 equivalents) and potassium carbonate (0.2 g, 2.7 equivalents) was introduced to the reaction at about 70 to about 75 °C. After the addition was completed, the reaction was allowed to progress for at least about 1 hour.
After this time had elapsed, water (1.4 mL) and dichloromethane (1.4 mL) were introduced to the reaction. The phases were separated, and the aqueous layer was extracted with dichloromethane. The combined organic layers were dried over magnesium sulfate, then were filtered and concentrated under reduced pressure. The resulting crude material was purified via silica gel chromatography to obtain G-la.
lR NMR (400 MHz, CDC13): δ 10.23 (t, J= 5.5 Hz, 1H), 8.39 (s, 1H), 6.60 (t, J= 8.1 Hz, 2H), 5.29 (dd, J= 9.5, 3.7 Hz, 2H), 4.57 (d, J= 5.4 Hz, 3H), 4.33 (dd, J = 12.8, 3.8 Hz, 1H), 4.02 – 3.87 (m, 1H), 3.94 (s, 3H), 2.06 – 1.88 (m, 4H), 1.78 (dd, J = 17.2, 7.5 Hz, 1H), 1.55 – 1.46 (m, 1H). 13C MR (100 MHz, CDC13): δ 174.53, 163.75, 162.33 (dd, J= 249.4, 15.7, 15.7 Hz), 161.86 (ddd, J= 250.4, 14.9, 10.9 Hz), 154.18, 154.15, 142.44, 129.75, 1 18.88, 1 10.58 (ddd, J= 19.8, 4.7, 4.7 Hz), 100.42 (m), 77.64, 74.40, 61.23, 54.79, 51.13, 38.31, 30.73, 29.55, 28.04. LCMS, Calculated: 463.14, Found: 464.15 (M+H).
Γ. Deprotection of G-la to form a compound of Formula la:

G-la (14 g) was suspended in acetonitrile (150 mL) and dichloromethane (150 mL). MgBr2 (12 g) was added. The reaction was heated to 40 to 50 °C for approximately 10 min before being cooled to room temperature. The reaction was poured into 0.5M HC1 (140 mL) and the layers separated. The organic layer was washed with water (70 mL), and the organic layer was then concentrated. The crude product was purified by silica gel chromatography (100% dichloromethane up to 6% ethanol/dichloromethane) to afford la.

REFERENCES
Patent Submitted Granted
POLYCYCLIC-CARBAMOYLPYRIDONE COMPOUNDS AND THEIR PHARMACEUTICAL USE [US2014221356] 2013-12-19 2014-08-07
US9216996 Dec 19, 2013 Dec 22, 2015 Gilead Sciences, Inc. Substituted 2,3,4,5,7,9,13,13a-octahydropyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazepines and methods for treating viral infections



 see..........http://newdrugapprovals.org/2015/12/28/gs-9883-bictegravir-an-hiv-1-integrase-inhibitor/

//////////
C1CC2CC1N3C(O2)CN4C=C(C(=O)C(=C4C3=O)O)C(=O)NCC5=C(C=C(C=C5F)F)F
OR
c1c(cc(c(c1F)CNC(=O)c2cn3c(c(c2=O)O)C(=O)N4[C@H]5CC[C@H](C5)O[C@@H]4C3)F)F

see.......gravir series.............http://medcheminternational.blogspot.in/p/ravir-series.html

 

 

 


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