Ombitasvir; ABT-267; ABT 267; UNII-2302768XJ8; 1258226-87-7;

Anti-Viral Compounds [US2010317568]

http://pubs.acs.org/doi/suppl/10.1021/jm401398x/suppl_file/jm401398x_si_001.pdf

WO 2011156578

dimethyl (2S,2^,S)-l,l ‘-((2S,2’S)-2,2′-(4,4’-((2S,5S)-l-(4-fert-butylphenyl)pyrrolidine- 2,5-diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3- methyl- l-oxobutane-2,l-diyl)dicarbamate

hereinafter Compound IA),..http://www.google.com/patents/WO2011156578A1?cl=en

PATENT

US 20100317568

https://www.google.co.in/patents/US20100317568

Example 34

Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diyl)dicarbamate and

Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2R,5R)-1-(4-ter/’-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 – oxobutane-2, 1 -diyl)dicarbamate

Example 34A l-(4-fer?-butylphenyl)-2,5-bis(4-nitrophenyl)pyrrolidine The product from Example 1C (3.67 g, 7.51 mmol) and 4-tert-butylaniline (11.86 ml, 75 mmol) in DMF (40 ml) was stirred under nitrogen at 50 °C for 4 h. The resulting mixture was diluted into ethyl acetate, treated with IM HCl, stirred for 10 minutes and filtered to remove solids. The filtrate organic layer was washed twice with brine, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (5% to 30%) to give a solid. The solid was triturated in a minimal volume of 1 :9 ethyl acetate/hexane to give a light yellow solid as a mixture of trans and cis isomers (1.21 g, 36%).

Example 34B 4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)dianiline and 4,4′-((2R,5R)-1-(4-fert- butylphenyl)pyrrolidine-2,5-diyl)dianiline To a solution of the product from Example 34A (1.1 g, 2.47 mmol) in ethanol (20 ml) and

THF (20 ml) was added PtC>₂ (0.22 g, 0.97 mmol) in a 50 ml pressure bottle and stirred under 30 psi hydrogen at room temperature for 1 h. The mixture was filtered through a nylon membrane and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (20% to 60%). The title compound eluted as the first of 2 stereoisomers (trans isomer, 0.51 g, 54%).

Example 34C

(2S,2’S)-tert-Butyl 2,2′-(4,4′-((2S,5S)-1-(4-fer/’-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)dipyrrolidine- 1 -carboxylate and (2S,2’S)-tert-Butyl 2,2′- (4,4′-((2R,5R)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)dipyrrolidine-1-carboxylate To a mixture of the product from Example 34B (250 mg, 0.648 mmol), (S)-1-(tert- butoxycarbonyl)pyrrolidine-2-carboxylic acid (307 mg, 1.427 mmol) and HATU (542 mg, 1.427 mmol) in DMSO (10 ml) was added Hunig’s base (0.453 ml, 2.59 mmol). The reaction mixture was stirred at room temperature for 1 h. The mixture was partitioned with ethyl acetate and water. The organic layer was washed with brine, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (10% to 50%) to give the title compound (500 mg, 99%).

Example 34D

(2S,2’S)-N,N’-(4,4′-((2S,5S)-1-(4-ter/’-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))dipyrrolidine-2-carboxamide and (2S,2’S)-N,N’-(4,4′-((2R,5R)-1-(4-tert- butylphenyl)pyrrolidine-2,5-diyl)bis(4,l-phenylene))dipyrrolidine-2-carboxamide To the product from Example 34C (498 mg, 0.638 mmol) in dichloromethane (4 ml) was added TFA (6 ml). The reaction mixture was stirred at room temperature for 1 h and concentrated in vacuo. The residue was partitioned between 3: 1 CHCl₃dsopropyl alcohol and saturated aq. NaHCO₃. The aqueous layer was extracted by 3: 1 CHCl₃:isopropyl alcohol again. The combined organic layers were dried over

filtered and concentrated to give the title compound (345 mg, 93%).

Example 34E Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-fert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diyl)dicarbamate and

Dimethyl (2S,2’S)-1, r-((2S,2’S)-2,2′-(4,4′-((2R,5R)-1-(4-fert-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 – oxobutane-2, 1 -diyl)dicarbamate

The product from Example 34D (29.0 mg, 0.050 mmol), (S)-2-(methoxycarbonylamino)-3- methylbutanoic acid (19.27 mg, 0.110 mmol), EDAC (21.09 mg, 0.110 mmol), HOBT (16.85 mg,

0.110 mmol) and N-methylmorpholine (0.027 ml, 0.250 mmol) were combined in DMF (2 ml). The reaction mixture was stirred at room temperature for 3 h. The mixture was partitioned with ethyl acetate and water. The organic layer was washed with brine twice, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (50% to 80%) to give a solid. The solid was triturated with ethyl acetate/hexane to give the title compound (13 mg, 29%). ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.85 – 0.95 (m, 12 H) 1.11 (s, 9 H) 1.59 – 1.65 (m, 2 H) 1.79 – 2.04 (m, 8 H) 2.10 – 2.18 (m, 2 H) 2.41-2.46 (m, 2H) 3.52 (s, 6 H)

3.57 – 3.67 (m, 2 H) 3.76 – 3.86 (m, 2 H) 4.00 (t, J=7.56 Hz, 2 H) 4.39 – 4.46 (m, 2 H) 5.15 (d, J=7.00

Hz, 2 H) 6.17 (d, J=7.70 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=7.37 Hz, 4 H) 7.30 (d, J=8.20

Hz, 2 H) 7.50 (d, J=8.24 Hz, 4 H) 9.98 (s, 2 H); (ESI+) m/z 895 (M+H)+. The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Example 35

Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diyl)dicarbamate

The product from Example 34E was purified by chiral chromatography on a Chiralpak AD-H semi-prep column eluting with a 2:1 mixture of hexane:(2: l isopropyl alcohol: EtOH). The title compound was the first of the 2 diastereomers to elute. ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.88 (d, J=6.61 Hz, 6 H) 0.93 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.42 Hz, 2 H) 1.80 – 2.04 (m, 8 H) 2.09 – 2.19 (m, 2 H) 2.44 – 2.47 (m, 2 H) 3.52 (s, 6 H) 3.59 – 3.66 (m, 2 H) 3.77 – 3.84 (m, 2 H) 4.02 (t, J=8.40 Hz, 2 H) 4.42 (dd, J=7.86, 4.83 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.67 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.50 (d, J=8.35 Hz, 4 H) 9.98 (s, 2 H). The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV Ib- Conl replicon assays in the presence of 5% FBS.

Example 36 Dimethyl (2S,2’S)-1, r-((2S,2’S)-2,2′-(4,4′-((2R,5R)-1-(4-fert-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 – oxobutane-2, 1 -diyl)dicarbamate

The product from Example 34E was purified by chiral chromatography on a Chiralpak AD-H semi-prep column eluting with a 2:1 mixture of hexane:(2: l isopropyl alcohol: EtOH). The title compound was the second of 2 diastereomers to elute. ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.87

(d, J=6.51 Hz, 6 H) 0.92 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.53 Hz, 2 H) 1.82 – 2.04 (m, 8

H) 2.09-2.18 (m, 2 H) 2.41 – 2.47 (m, 2 H) 3.52 (s, 6 H) 3.58 – 3.67 (m, 2 H) 3.75 – 3.84 (m, 2 H) 4.02

(t, J=7.26 Hz, 2 H) 4.43 (dd, J=7.92, 4.88 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.78 Hz, 2 H) 6.94 (d, J=8.67 Hz, 2 H) 7.12 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.49 (d, J=8.46 Hz, 4 H)

9.98 (s, 2 H). The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Example 37 Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-fert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diyl)dicarbamate

Example 37A (S)-2,5-dioxopyrrolidin-1-yl 2-(methoxycarbonylamino)-3-methylbutanoate To a mixture of (S)-2-(methoxycarbonylamino)-3-methylbutanoic acid (19.66 g, 112 mmol) and N-hydroxysuccinimide (13.29g, 116 mmol) was added ethyl acetate (250 ml), and the mixture was cooled to 0-5 °C. Diisopropylcarbodiimide (13.88 g, 110 mmol) was added and the reaction mixture was stirred at 0-5 °C for about 1 hour. The reaction mixture was warmed to room temperature. The solids (diisopropylurea by-product) were filtered and rinsed with ethyl acetate. The filtrate was concentrated in vacuo to an oil. Isopropyl alcohol (200 ml) was added to the oil and the mixture was heated to about 50 °C to obtain a homogeneous solution. Upon cooling, crystalline solids formed. The solids were filtered and washed with isopropyl alcohol (3 x 20 ml) and dried to give the title compound as a white solid (23.2 g, 77% yield).

Example 37B

(S)- 1 -((S)-2-(methoxycarbonylamino)-3-methylbutanoyl)pyrrolidine-2-carboxylic acid To a mixture of L-proline (4.44g, 38.6 mmol), water (20 ml), acetonitrile (20 ml) and DIEA (9.5 g, 73.5 mmol) was added a solution of the product from Example 37A (1Og, 36.7 mmol) in acetonitrile (20 inL) over 10 minutes. The reaction mixture was stirred overnight at room temperature. The solution was concentrated under vacuum to remove the acetonitrile. To the resulting clear water solution was added 6N HCl (9 ml) until pH ~ 2 .The solution was transferred to a separatory funnel and 25% NaCl (10 ml) was added and the mixture was extracted with ethyl acetate (75 ml), and then again with ethyl acetate (6 x 20 ml), and the combined extracts were washed with 25% NaCl (2 x 10ml). The solvent was evaporated to give a thick oil. Heptane was added and the solvent was evaporated to give a foam, which was dried under high vacuum. Diethyl ether was added and the solvent was evaporated to give a foam, which was dried under high vacuum to give the title compound (10.67g) as a white solid.

The compound of Example 37B can also be prepreared according to the following procedure: To a flask was charged L- valine (35 g, 299 mmol), IN sodium hydroxide solution (526 ml,

526 mmol) and sodium carbonate (17.42 g, 164 mmol). The mixture was stirred for 15 min to dissolve solids and then cooled to 15 °C. Methyl chloroformate (29.6 g, 314 mmol) was added slowly to the reaction mixture. The mixture was then stirred at rt for 30 min. The mixture was cooled to 15 °C and pH adjusted to -5.0 with concentrated HCl solution. 100 inL of 2-methytetrahydrofuran (2- MeTHF) was added and the adjustment of pH continued until the pH reached ~ 2.0. 150 mL of 2- MeTHF was added and the mixture was stirred for 15 min. Layers were separated and the aqueous layer extracted with 100 mL of 2-MeTHF. The combined organic layer was dried over anhyd Na₂SC^ and filtered, and Na₂SC^ cake was washed with 50 mL of 2-MeTHF. The product solution was concentrated to ~ 100 mL, chased with 120 mL of IPAc twice. 250 mL of heptanes was charged slowly and then the volume of the mixture was concentrated to 300 mL. The mixture was heated to 45 °C and 160 mL of heptanes charged. The mixture was cooled to rt in 2h, stirred for 30 min, filtered and washed with 2-MeTHF/heptanes mixture (1:7, 80 inL). The wetcake was dried at 55 °C for 24 h to give 47.1 g of Moc-L- VaI-OH product as a white solid (90%).

Moc-L- VaI-OH (15O g, 856 mmol), HOBt hydrate (138 g, 899 mmol) and DMF (1500 ml) were charged to a flask. The mixture was stirred for 15 min to give a clear solution. EDC hydrochloride (172 g, 899 mmol) was charged and mixed for 20 min. The mixture was cooled to 13

°C and (L)-proline benzyl ester hydrochloride (207 g, 856 mmol) charged. Triethylamine (109 g,

1079 mmol) was then charged in 30 min. The resulting suspension was mixed at rt for 1.5 h. The reaction mixture was cooled to 15 °C and 1500 mL of 6.7% NaHCO₃ charged in 1.5 h, followed by the addition of 1200 mL of water over 60 min. The mixture was stirred at rt for 30 min, filtered and washed with water/DMF mixture (1 :2, 250 mL) and then with water (1500 mL). The wetcake was dried at 55 °C for 24 h to give 282 g of product as a white solid (90%).

The resulting solids (40 g) and 5% Pd/ Alumina were charged to a Parr reactor followed by THF (160 mL). The reactor was sealed and purged with nitrogen (6 x 20 psig) followed by a hydrogen purge (6 x 30 psig). The reactor was pressurized to 30 psig with hydrogen and agitated at room temperature for approximately 15 hours. The resulting slurry was filtered through a GF/F filter and concentrated to approximately 135 g solution. Heptane was added (120 mL), and the solution was stirred until solids formed. After an addition 2 – 3 hours additional heptane was added drop-wise (240 mL), the slurry was stirred for approximately 1 hour, then filtered. The solids were dried to afford the title compound.

Example 37C

(lR,4R)-1,4-bis(4-nitrophenyl)butane-1,4-diyl dimethanesulfonate

The product from Example 32 (5.01 g, 13.39 mmol) was combined with 2- methyltetrahydrofuran (70 mL) and cooled to -5 °C, and N,N-diisopropylethylamine (6.81 g, 52.7 mmol) was added over 30 seconds. Separately, a solution of methanesulfonic anhydride (6.01 g, 34.5 mmol) in 2-methyltetrahydrofuran (30 mL) was prepared and added to the diol slurry over 3 min., maintaining the internal temperature between -15 °C and -25 °C. After mixing for 5 min at -15 °C, the cooling bath was removed and the reaction was allowed to warm slowly to 23 °C and mixed for 30 minutes. After reaction completion, the crude slurry was carried immediately into the next step.

Example 37D

(2S,5S)-1-(4-tert-butylphenyl)-2,5-bis(4-nitrophenyl)pyrrolidine

To the crude product solution from Example 37C (7.35 g, 13.39 mmol) was added 4-tert- butylaniline (13.4 g, 90 mmol) at 23 °C over 1 minute. The reaction was heated to 65 °C for 2 h. After completion, the reaction mixture was cooled to 23 °C and diluted with 2-methyltetrahydrofuran (100 mL) and 1 M HCl (150 mL). After partitioning the phases, the organic phase was treated with 1 M HCl (140 mL), 2-methyltetrahydrofuran (50 mL), and 25 wt% aq. NaCl (100 mL), and the phases were partitioned. The organic phase was washed with 25 wt% aq. NaCl (50 mL), dried over MgSO/_t, filtered, and concentrated in vacuo to approximately 20 mL. Heptane (30 mL) and additional 2- methyltetrahydrofuran were added in order to induce crystallization. The slurry was concentrated further, and additional heptane (40 mL) was slowly added and the slurry was filtered, washing with 2- methyltetrahydrofuran:heptane (1:4, 20 mL). The solids were suspended in MeOH (46 mL) for 3 h, filtered, and the wet solid was washed with additional MeOH (18 mL). The solid was dried at 45 °C in a vacuum oven for 16 h to provide the title compound (3.08 g, 51% 2-step yield).

Example 37E

4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)dianiline

To a 160 ml Parr stirrer hydrogenation vessel was added the product from Example 37D (2 g, 4.49 mmol), followed by 60 ml of THF, and Raney Nickel Grace 2800 (1 g, 50 wt% (dry basis)) under a stream of nitrogen. The reactor was assembled and purged with nitrogen (8 x 20 psig) followed by purging with hydrogen (8 x 30 psig). The reactor was then pressurized to 30 psig with hydrogen and agitation (700 rpm) began and continued for a total of 16 h at room temperature. The slurry was filtered by vacuum filtration using a GF/F Whatman glass fiber filter. Evaporation of the filtrate to afford a slurry followed by the addition heptane and filtration gave the crude title compound, which was dried and used directly in the next step.

Example 37F dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4, l- phenylene)bis(azanediyl)bis(oxomethylene))bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diy 1) die arb amate To a solution of the product from Example 37E (1.64 g, 4.25 mmol) in DMF (20 ml), the product from Example 37B (2.89 g, 10.63 mmol), and HATU (4.04 g, 10.63 mmol) in DMF (15OmL) was added triethylamine (1.07 g, 10.63 mmol), and the solution was stirred at room temperature for 90 min. To the reaction mixture was poured 20 mL of water, and the white precipitate obtained was filtered, and the solid was washed with water (3×5 mL). The solid was blow dried for Ih. The crude material was loaded on a silica gel column and eluted with a gradient starting with ethyl acetate/ heptane (3/7), and ending with pure ethyl acetate. The desired fractions were combined and solvent distilled off to give a very light yellow solid, which was dried at 45 °C in a vacuum oven with nitrogen purge for 15 h to give the title compound (2.3 g, 61% yield). ¹H NMR (400 MHz, DMSO- D6) δ ppm 0.88 (d, J=6.61 Hz, 6 H) 0.93 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.42 Hz, 2 H) 1.80 – 2.04 (m, 8 H) 2.09 – 2.19 (m, 2 H) 2.44 – 2.47 (m, 2 H) 3.52 (s, 6 H) 3.59 – 3.66 (m, 2 H) 3.77 – 3.84 (m, 2 H) 4.02 (t, J=8.40 Hz, 2 H) 4.42 (dd, J=7.86, 4.83 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.67 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.50 (d, J=8.35 Hz, 4 H) 9.98 (s, 2 H).

Alternately, the product from example 37E (11.7 g, 85 wt%, 25.8 mmol) and the product from example 37B (15.45 g, 56.7 mmol) are suspended in EtOAc (117 mL), diisopropylethylamine (18.67 g, 144 mmol) is added and the solution is cooled to 0 °C. In a separate flask, 1-propanephosphonic acid cyclic anhydride (T3P^®) (46.0 g, 50 wt% in EtOAc, 72.2 mmol) was dissolved in EtOAc (58.5 mL), and charged to an addition funnel. The T₃P solution is added to the reaction mixture drop-wise over 3-4 h and stirred until the reaction is complete. The reaction is warmed to room temperature,and washed with IM HCl/7.5 wt% NaCl (100 mL), then washed with 5% NaHCO₃ (100 mL), then washed with 5% NaCl solution (100 mL). The solution was concentrated to approximately 60 mL, EtOH (300 mL) was added, and the solution was concentrated to 84 g solution.

A portion of the EtOH solution of product (29 g) was heated to 40 °C, and added 134 g 40 w% EtOH in H₂O. A slurry of seeds in 58 wt/wt% EtOH/H₂O was added, allowed to stir at 40 °C for several hours, then cooled to 0 °C. The slurry is then filtered, and washed with 58wt/wt% EtOH/H₂O. The product is dried at 40 – 60 °C under vacuum, and then rehydrated by placing a tray of water in the vacuum oven to give the title compound. The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

PATENT

http://www.google.com/patents/EP2337781A2?cl=en

Example 34

Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diyl)dicarbamate and

Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2R,5R)-1-(4-ter/’-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 – oxobutane-2, 1 -diyl)dicarbamate

Example 34A l-(4-fer?-butylphenyl)-2,5-bis(4-nitrophenyl)pyrrolidine The product from Example 1C (3.67 g, 7.51 mmol) and 4-tert-butylaniline (11.86 ml, 75 mmol) in DMF (40 ml) was stirred under nitrogen at 50 °C for 4 h. The resulting mixture was diluted into ethyl acetate, treated with IM HCl, stirred for 10 minutes and filtered to remove solids. The filtrate organic layer was washed twice with brine, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (5% to 30%) to give a solid. The solid was triturated in a minimal volume of 1 :9 ethyl acetate/hexane to give a light yellow solid as a mixture of trans and cis isomers (1.21 g, 36%).

Example 34B 4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)dianiline and 4,4′-((2R,5R)-1-(4-fert- butylphenyl)pyrrolidine-2,5-diyl)dianiline To a solution of the product from Example 34A (1.1 g, 2.47 mmol) in ethanol (20 ml) and

THF (20 ml) was added PtC>₂ (0.22 g, 0.97 mmol) in a 50 ml pressure bottle and stirred under 30 psi hydrogen at room temperature for 1 h. The mixture was filtered through a nylon membrane and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (20% to 60%). The title compound eluted as the first of 2 stereoisomers (trans isomer, 0.51 g, 54%).

Example 34C

(2S,2’S)-tert-Butyl 2,2′-(4,4′-((2S,5S)-1-(4-fer/’-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)dipyrrolidine- 1 -carboxylate and (2S,2’S)-tert-Butyl 2,2′- (4,4′-((2R,5R)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)dipyrrolidine-1-carboxylate To a mixture of the product from Example 34B (250 mg, 0.648 mmol), (S)-1-(tert- butoxycarbonyl)pyrrolidine-2-carboxylic acid (307 mg, 1.427 mmol) and HATU (542 mg, 1.427 mmol) in DMSO (10 ml) was added Hunig’s base (0.453 ml, 2.59 mmol). The reaction mixture was stirred at room temperature for 1 h. The mixture was partitioned with ethyl acetate and water. The organic layer was washed with brine, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (10% to 50%) to give the title compound (500 mg, 99%).

Example 34D

(2S,2’S)-N,N’-(4,4′-((2S,5S)-1-(4-ter/’-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))dipyrrolidine-2-carboxamide and (2S,2’S)-N,N’-(4,4′-((2R,5R)-1-(4-tert- butylphenyl)pyrrolidine-2,5-diyl)bis(4,l-phenylene))dipyrrolidine-2-carboxamide To the product from Example 34C (498 mg, 0.638 mmol) in dichloromethane (4 ml) was added TFA (6 ml). The reaction mixture was stirred at room temperature for 1 h and concentrated in vacuo. The residue was partitioned between 3: 1 CHCl₃dsopropyl alcohol and saturated aq. NaHCO₃. The aqueous layer was extracted by 3: 1 CHCl₃:isopropyl alcohol again. The combined organic layers were dried over

filtered and concentrated to give the title compound (345 mg, 93%).

Example 34E Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-fert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diyl)dicarbamate and

Dimethyl (2S,2’S)-1, r-((2S,2’S)-2,2′-(4,4′-((2R,5R)-1-(4-fert-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 – oxobutane-2, 1 -diyl)dicarbamate

The product from Example 34D (29.0 mg, 0.050 mmol), (S)-2-(methoxycarbonylamino)-3- methylbutanoic acid (19.27 mg, 0.110 mmol), EDAC (21.09 mg, 0.110 mmol), HOBT (16.85 mg,

0.110 mmol) and N-methylmorpholine (0.027 ml, 0.250 mmol) were combined in DMF (2 ml). The reaction mixture was stirred at room temperature for 3 h. The mixture was partitioned with ethyl acetate and water. The organic layer was washed with brine twice, dried with sodium sulfate, filtered and evaporated. The residue was purified by chromatography on silica gel eluting with ethyl acetate in hexane (50% to 80%) to give a solid. The solid was triturated with ethyl acetate/hexane to give the title compound (13 mg, 29%). ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.85 – 0.95 (m, 12 H) 1.11 (s, 9 H) 1.59 – 1.65 (m, 2 H) 1.79 – 2.04 (m, 8 H) 2.10 – 2.18 (m, 2 H) 2.41-2.46 (m, 2H) 3.52 (s, 6 H)

3.57 – 3.67 (m, 2 H) 3.76 – 3.86 (m, 2 H) 4.00 (t, J=7.56 Hz, 2 H) 4.39 – 4.46 (m, 2 H) 5.15 (d, J=7.00

Hz, 2 H) 6.17 (d, J=7.70 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=7.37 Hz, 4 H) 7.30 (d, J=8.20

Hz, 2 H) 7.50 (d, J=8.24 Hz, 4 H) 9.98 (s, 2 H); (ESI+) m/z 895 (M+H)+. The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Example 35

Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diyl)dicarbamate

The product from Example 34E was purified by chiral chromatography on a Chiralpak AD-H semi-prep column eluting with a 2:1 mixture of hexane:(2: l isopropyl alcohol: EtOH). The title compound was the first of the 2 diastereomers to elute. ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.88 (d, J=6.61 Hz, 6 H) 0.93 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.42 Hz, 2 H) 1.80 – 2.04 (m, 8 H) 2.09 – 2.19 (m, 2 H) 2.44 – 2.47 (m, 2 H) 3.52 (s, 6 H) 3.59 – 3.66 (m, 2 H) 3.77 – 3.84 (m, 2 H) 4.02 (t, J=8.40 Hz, 2 H) 4.42 (dd, J=7.86, 4.83 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.67 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.50 (d, J=8.35 Hz, 4 H) 9.98 (s, 2 H). The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV Ib- Conl replicon assays in the presence of 5% FBS.

Example 36 Dimethyl (2S,2’S)-1, r-((2S,2’S)-2,2′-(4,4′-((2R,5R)-1-(4-fert-butylphenyl)pyrrolidine-2,5- diyl)bis(4, 1 -phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 – oxobutane-2, 1 -diyl)dicarbamate

The product from Example 34E was purified by chiral chromatography on a Chiralpak AD-H semi-prep column eluting with a 2:1 mixture of hexane:(2: l isopropyl alcohol: EtOH). The title compound was the second of 2 diastereomers to elute. ¹H NMR (400 MHz, DMSO-D6) δ ppm 0.87

(d, J=6.51 Hz, 6 H) 0.92 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.53 Hz, 2 H) 1.82 – 2.04 (m, 8

H) 2.09-2.18 (m, 2 H) 2.41 – 2.47 (m, 2 H) 3.52 (s, 6 H) 3.58 – 3.67 (m, 2 H) 3.75 – 3.84 (m, 2 H) 4.02

(t, J=7.26 Hz, 2 H) 4.43 (dd, J=7.92, 4.88 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.78 Hz, 2 H) 6.94 (d, J=8.67 Hz, 2 H) 7.12 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.49 (d, J=8.46 Hz, 4 H)

9.98 (s, 2 H). The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Example 37 Dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-fert-butylphenyl)pyrrolidine-2,5-diyl)bis(4,l- phenylene))bis(azanediyl)bis(oxomethylene)bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diyl)dicarbamate

Example 37A (S)-2,5-dioxopyrrolidin-1-yl 2-(methoxycarbonylamino)-3-methylbutanoate To a mixture of (S)-2-(methoxycarbonylamino)-3-methylbutanoic acid (19.66 g, 112 mmol) and N-hydroxysuccinimide (13.29g, 116 mmol) was added ethyl acetate (250 ml), and the mixture was cooled to 0-5 °C. Diisopropylcarbodiimide (13.88 g, 110 mmol) was added and the reaction mixture was stirred at 0-5 °C for about 1 hour. The reaction mixture was warmed to room temperature. The solids (diisopropylurea by-product) were filtered and rinsed with ethyl acetate. The filtrate was concentrated in vacuo to an oil. Isopropyl alcohol (200 ml) was added to the oil and the mixture was heated to about 50 °C to obtain a homogeneous solution. Upon cooling, crystalline solids formed. The solids were filtered and washed with isopropyl alcohol (3 x 20 ml) and dried to give the title compound as a white solid (23.2 g, 77% yield).

Example 37B

(S)- 1 -((S)-2-(methoxycarbonylamino)-3-methylbutanoyl)pyrrolidine-2-carboxylic acid To a mixture of L-proline (4.44g, 38.6 mmol), water (20 ml), acetonitrile (20 ml) and DIEA (9.5 g, 73.5 mmol) was added a solution of the product from Example 37A (1Og, 36.7 mmol) in acetonitrile (20 inL) over 10 minutes. The reaction mixture was stirred overnight at room temperature. The solution was concentrated under vacuum to remove the acetonitrile. To the resulting clear water solution was added 6N HCl (9 ml) until pH ~ 2 .The solution was transferred to a separatory funnel and 25% NaCl (10 ml) was added and the mixture was extracted with ethyl acetate (75 ml), and then again with ethyl acetate (6 x 20 ml), and the combined extracts were washed with 25% NaCl (2 x 10ml). The solvent was evaporated to give a thick oil. Heptane was added and the solvent was evaporated to give a foam, which was dried under high vacuum. Diethyl ether was added and the solvent was evaporated to give a foam, which was dried under high vacuum to give the title compound (10.67g) as a white solid.

The compound of Example 37B can also be prepreared according to the following procedure: To a flask was charged L- valine (35 g, 299 mmol), IN sodium hydroxide solution (526 ml,

526 mmol) and sodium carbonate (17.42 g, 164 mmol). The mixture was stirred for 15 min to dissolve solids and then cooled to 15 °C. Methyl chloroformate (29.6 g, 314 mmol) was added slowly to the reaction mixture. The mixture was then stirred at rt for 30 min. The mixture was cooled to 15 °C and pH adjusted to -5.0 with concentrated HCl solution. 100 inL of 2-methytetrahydrofuran (2- MeTHF) was added and the adjustment of pH continued until the pH reached ~ 2.0. 150 mL of 2- MeTHF was added and the mixture was stirred for 15 min. Layers were separated and the aqueous layer extracted with 100 mL of 2-MeTHF. The combined organic layer was dried over anhyd Na₂SC^ and filtered, and Na₂SC^ cake was washed with 50 mL of 2-MeTHF. The product solution was concentrated to ~ 100 mL, chased with 120 mL of IPAc twice. 250 mL of heptanes was charged slowly and then the volume of the mixture was concentrated to 300 mL. The mixture was heated to 45 °C and 160 mL of heptanes charged. The mixture was cooled to rt in 2h, stirred for 30 min, filtered and washed with 2-MeTHF/heptanes mixture (1:7, 80 inL). The wetcake was dried at 55 °C for 24 h to give 47.1 g of Moc-L- VaI-OH product as a white solid (90%).

Moc-L- VaI-OH (15O g, 856 mmol), HOBt hydrate (138 g, 899 mmol) and DMF (1500 ml) were charged to a flask. The mixture was stirred for 15 min to give a clear solution. EDC hydrochloride (172 g, 899 mmol) was charged and mixed for 20 min. The mixture was cooled to 13

°C and (L)-proline benzyl ester hydrochloride (207 g, 856 mmol) charged. Triethylamine (109 g,

1079 mmol) was then charged in 30 min. The resulting suspension was mixed at rt for 1.5 h. The reaction mixture was cooled to 15 °C and 1500 mL of 6.7% NaHCO₃ charged in 1.5 h, followed by the addition of 1200 mL of water over 60 min. The mixture was stirred at rt for 30 min, filtered and washed with water/DMF mixture (1 :2, 250 mL) and then with water (1500 mL). The wetcake was dried at 55 °C for 24 h to give 282 g of product as a white solid (90%).

The resulting solids (40 g) and 5% Pd/ Alumina were charged to a Parr reactor followed by THF (160 mL). The reactor was sealed and purged with nitrogen (6 x 20 psig) followed by a hydrogen purge (6 x 30 psig). The reactor was pressurized to 30 psig with hydrogen and agitated at room temperature for approximately 15 hours. The resulting slurry was filtered through a GF/F filter and concentrated to approximately 135 g solution. Heptane was added (120 mL), and the solution was stirred until solids formed. After an addition 2 – 3 hours additional heptane was added drop-wise (240 mL), the slurry was stirred for approximately 1 hour, then filtered. The solids were dried to afford the title compound.

Example 37C

(lR,4R)-1,4-bis(4-nitrophenyl)butane-1,4-diyl dimethanesulfonate

The product from Example 32 (5.01 g, 13.39 mmol) was combined with 2- methyltetrahydrofuran (70 mL) and cooled to -5 °C, and N,N-diisopropylethylamine (6.81 g, 52.7 mmol) was added over 30 seconds. Separately, a solution of methanesulfonic anhydride (6.01 g, 34.5 mmol) in 2-methyltetrahydrofuran (30 mL) was prepared and added to the diol slurry over 3 min., maintaining the internal temperature between -15 °C and -25 °C. After mixing for 5 min at -15 °C, the cooling bath was removed and the reaction was allowed to warm slowly to 23 °C and mixed for 30 minutes. After reaction completion, the crude slurry was carried immediately into the next step.

Example 37D

(2S,5S)-1-(4-tert-butylphenyl)-2,5-bis(4-nitrophenyl)pyrrolidine

To the crude product solution from Example 37C (7.35 g, 13.39 mmol) was added 4-tert- butylaniline (13.4 g, 90 mmol) at 23 °C over 1 minute. The reaction was heated to 65 °C for 2 h. After completion, the reaction mixture was cooled to 23 °C and diluted with 2-methyltetrahydrofuran (100 mL) and 1 M HCl (150 mL). After partitioning the phases, the organic phase was treated with 1 M HCl (140 mL), 2-methyltetrahydrofuran (50 mL), and 25 wt% aq. NaCl (100 mL), and the phases were partitioned. The organic phase was washed with 25 wt% aq. NaCl (50 mL), dried over MgSO/_t, filtered, and concentrated in vacuo to approximately 20 mL. Heptane (30 mL) and additional 2- methyltetrahydrofuran were added in order to induce crystallization. The slurry was concentrated further, and additional heptane (40 mL) was slowly added and the slurry was filtered, washing with 2- methyltetrahydrofuran:heptane (1:4, 20 mL). The solids were suspended in MeOH (46 mL) for 3 h, filtered, and the wet solid was washed with additional MeOH (18 mL). The solid was dried at 45 °C in a vacuum oven for 16 h to provide the title compound (3.08 g, 51% 2-step yield).

Example 37E

4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)dianiline

To a 160 ml Parr stirrer hydrogenation vessel was added the product from Example 37D (2 g, 4.49 mmol), followed by 60 ml of THF, and Raney Nickel Grace 2800 (1 g, 50 wt% (dry basis)) under a stream of nitrogen. The reactor was assembled and purged with nitrogen (8 x 20 psig) followed by purging with hydrogen (8 x 30 psig). The reactor was then pressurized to 30 psig with hydrogen and agitation (700 rpm) began and continued for a total of 16 h at room temperature. The slurry was filtered by vacuum filtration using a GF/F Whatman glass fiber filter. Evaporation of the filtrate to afford a slurry followed by the addition heptane and filtration gave the crude title compound, which was dried and used directly in the next step.

Example 37F dimethyl (2S,2’S)-l,r-((2S,2’S)-2,2′-(4,4′-((2S,5S)-1-(4-tert-butylphenyl)pyrrolidine-2,5-diyl)bis(4, l- phenylene)bis(azanediyl)bis(oxomethylene))bis(pyrrolidine-2, 1 -diyl))bis(3-methyl- 1 -oxobutane-2, 1 – diy 1) die arb amate To a solution of the product from Example 37E (1.64 g, 4.25 mmol) in DMF (20 ml), the product from Example 37B (2.89 g, 10.63 mmol), and HATU (4.04 g, 10.63 mmol) in DMF (15OmL) was added triethylamine (1.07 g, 10.63 mmol), and the solution was stirred at room temperature for 90 min. To the reaction mixture was poured 20 mL of water, and the white precipitate obtained was filtered, and the solid was washed with water (3×5 mL). The solid was blow dried for Ih. The crude material was loaded on a silica gel column and eluted with a gradient starting with ethyl acetate/ heptane (3/7), and ending with pure ethyl acetate. The desired fractions were combined and solvent distilled off to give a very light yellow solid, which was dried at 45 °C in a vacuum oven with nitrogen purge for 15 h to give the title compound (2.3 g, 61% yield). ¹H NMR (400 MHz, DMSO- D6) δ ppm 0.88 (d, J=6.61 Hz, 6 H) 0.93 (d, J=6.72 Hz, 6 H) 1.11 (s, 9 H) 1.63 (d, J=5.42 Hz, 2 H) 1.80 – 2.04 (m, 8 H) 2.09 – 2.19 (m, 2 H) 2.44 – 2.47 (m, 2 H) 3.52 (s, 6 H) 3.59 – 3.66 (m, 2 H) 3.77 – 3.84 (m, 2 H) 4.02 (t, J=8.40 Hz, 2 H) 4.42 (dd, J=7.86, 4.83 Hz, 2 H) 5.14 (d, J=6.18 Hz, 2 H) 6.17 (d, J=8.67 Hz, 2 H) 6.94 (d, J=8.78 Hz, 2 H) 7.13 (d, J=8.46 Hz, 4 H) 7.31 (d, J=8.35 Hz, 2 H) 7.50 (d, J=8.35 Hz, 4 H) 9.98 (s, 2 H).

Alternately, the product from example 37E (11.7 g, 85 wt%, 25.8 mmol) and the product from example 37B (15.45 g, 56.7 mmol) are suspended in EtOAc (117 mL), diisopropylethylamine (18.67 g, 144 mmol) is added and the solution is cooled to 0 °C. In a separate flask, 1-propanephosphonic acid cyclic anhydride (T3P^®) (46.0 g, 50 wt% in EtOAc, 72.2 mmol) was dissolved in EtOAc (58.5 mL), and charged to an addition funnel. The T₃P solution is added to the reaction mixture drop-wise over 3-4 h and stirred until the reaction is complete. The reaction is warmed to room temperature,and washed with IM HCl/7.5 wt% NaCl (100 mL), then washed with 5% NaHCO₃ (100 mL), then washed with 5% NaCl solution (100 mL). The solution was concentrated to approximately 60 mL, EtOH (300 mL) was added, and the solution was concentrated to 84 g solution.

A portion of the EtOH solution of product (29 g) was heated to 40 °C, and added 134 g 40 w% EtOH in H₂O. A slurry of seeds in 58 wt/wt% EtOH/H₂O was added, allowed to stir at 40 °C for several hours, then cooled to 0 °C. The slurry is then filtered, and washed with 58wt/wt% EtOH/H₂O. The product is dried at 40 – 60 °C under vacuum, and then rehydrated by placing a tray of water in the vacuum oven to give the title compound. The title compound showed an EC₅₀ value of less than about 0.1 nM in HCV lb-Conl replicon assays in the presence of 5% FBS.

Intermediates

Example 32

( 1 R,4R)- 1 ,4-bis(4-mtrophenyl)butane- 1 ,4-diol

To (S)-(-)-α,α-diphenyl-2-pyrrohdinemethanol (2 71 g, 10 70 mmol) was added THF (80 mL) at 23 °C The very thin suspension was treated with t₁₁methyl borate (1 44 g, 13 86 mmol) over 30 seconds, and the resulting solution was mixed at 23 °C for 1 h The solution was cooled to 16-19 °C, and N,N-diethylanilme borane (21 45 g, 132 mmol) was added dropwise via syringe over 3-5 mm (caution vigorous H₂ evolution), while the internal temperature was maintained at 16-19 °C After 15 mm, the H₂ evolution had ceased To a separate vessel was added the product from Example IA (22 04 g, 95 wt%, 63 8 mmol), followed by THF (80 mL), to form an orange slurry After cooling the slurry to 11 °C, the borane solution was transferred via cannula into the dione slurry over 3-5 min During this period, the internal temperature of the slurry rose to 16 °C After the addition was complete, the reaction was maintained at 20-27 °C for an additional 2 5 h After reaction completion, the mixture was cooled to 5 °C and methanol (16 7 g, 521 mmol) was added dropwise over 5-10 mm, maintaining an internal temperature <20 °C (note vigorous H₂ evolution) After the exotherm had ceased (ca 10 mm), the temperature was adjusted to 23 °C, and the reaction was mixed until complete dissolution of the solids had occurred Ethyl acetate (300 mL) and 1 M HCl (120 mL) were added, and the phases were partitioned The organic phase was then washed successively with 1 M HCl (2 x 120 mL), H₂O (65 mL), and 10% aq NaCl (65 mL) The orgamcs were dried over MgSO₄, filtered, and concentrated in vacuo Crystallization of the product occurred during the concentration The slurry was warmed to 50 °C, and heptane (250 inL) was added over 15 min. The slurry was then allowed to mix at 23 °C for 30 min and filtered. The wet cake was washed with 3: 1 heptane:ethyl acetate (75 mL), and the orange, crystalline solids were dried at 45 °C for 24 h to provide the title compound (15.35 g, 99.3% ee, 61% yield), which was contaminated with 11% of the meso isomer (vs. dl isomer).