反应详情

To (S)-1-(((9H-fluoren-9-yl)methoxy)carbonyl)-2-methylpyrrolidine-2-carboxylic acid (intermediate LS30; 1.5 g; 4.3 mmol) in 50 mL DMF was added sequentially 2-amino-1-(4-bromophenyl)ethanone hydrochloride (1.2 g; 4.7 mmol), HOAT (290 mg; 2.1 mmol), Hunig's base (0.7 mL; 4.3 mmol) and EDCI (1.2 g; 6.4 mmol). After 1 h, the reaction mixture was poured into 150 mL water and allowed to stir for 15 min before filtering the resultant precipitate which was dissolved in dichloromethane and dried over magnesium sulfate. The dichloromethane mixture was filtered and applied to a Biotage 40 samplet. Chromatography on a 40M column (25 to 60% ethyl acetate/hexane over 1200 mL) provided (S)-(9H-fluoren-9-yl)methyl 2-(2-(4-bromophenyl)-2-oxoethylcarbamoyl)-2-methylpyrrolidine-1-carboxylate (intermediate LS31; 2.4 g; quant) as a yellow foam. LC (Cond'n 11): RT=3.75 min; MS: Anal. Calcd. for [M+H]+ C29H27BrN2O4: 547.1. found 547.0. Step b: A mixture of ammonium acetate (844 mg; 10.97 mmol) and (S)-(9H-fluoren-9-yl)methyl 2-(2-(4-bromophenyl)-2-oxoethylcarbamoyl)-2-methylpyrrolidine-1-carboxylate (intermediate LS31; 1.00 g; 1.83 mmol) was heated to 140° C. in 25 mL xylene for 2.5 h at which time the reaction mixture was concentrated and loaded with dichloromethane onto a Biotage 40 samplet. Purification via Biotage (5 to 60% ethyl acetate/hexane over 1000 mL with 400 mL hold time) provided (S)-(9H-fluoren-9-yl)methyl 2-(5-(4-bromophenyl)-1H-imidazol-2-yl)-2-methylpyrrolidine-1-carboxylate (intermediate LS32; 469 mg; 49%) as an amber liquid. LC (Cond'n 12): RT=3.09 min; MS: Anal. Calcd. for [M+H]+ C29H26BrN3O2: 528.1. found 528.5. Step c: To (S)-(9H-fluoren-9-yl)methyl 2-(5-(4-bromophenyl)-1H-imidazol-2-yl)-2-methylpyrrolidine-1-carboxylate (intermediate LS32; 329 mg; 0.62 mmol) in 3 mL DMF was added 1.5 mL piperidine. The reaction mixture was concentrated via a nitrogen stream overnite. The resultant residue was washed with hexane and passed through an MCX cartridge (Oasis; 6 g; preconditioned with two column lengths of methanol). The cartridge was washed with two column lengths of methanol and product was eluted with ammonia/methanol. Concentration provided 193 mg of (S)-5-(4-bromophenyl)-2-(2-methylpyrrolidin-2-yl)-1H-imidazole which was dissolved in 6 mL dichloromethane and combined with di-t-butyldicarbonate (413 mg; 1.89 mmol), DMAP (15 mg; 0.13 mmol) and TEA (0.17 mL; 1.30 mmol). After 48 h, the reaction mixture was concentrated and purified via chromatography on a Biotage system providing (S)-tert-butyl 5-(4-bromophenyl)-2-(1-(tert-butoxycarbonyl)-2-methylpyrrolidin-2-yl)-1H-imidazole-1-carboxylate (intermediate LS33; 150 mg; 48%) as an off white solid. LC (Cond'n 5): RT=3.75 min; MS: Anal. Calcd. for [M+H]+ C24H32BrN3O4: 506.2. found 506.4 Step d: (S)-tert-butyl 2-(5-(4′-(2-((S)-1-(tert-butoxycarbonyl)pyrrolidin-2-yl)-1H-imidazol-5-yl)biphenyl-4-yl)-1H-imidazol-2-yl)-2-methylpyrrolidine-1-carboxylate (intermediate LS34) was prepared in a similar fashion to the preparation of 1d employing intermediate LS33 in place of 1b. 1H NMR (300 MHz, DMSO-d6; 100° C.) δ ppm 1.18-1.29 (m, 9H) 1.29-1.40 (m, 9H) 1.75-1.82 (m, 3H) 1.81-2.39 (m, 8H) 3.35-3.75 (m, 4H) 4.81-4.92 (m, 1H) 7.36-7.45 (m, 1H) 7.57-7.74 (m, 5H) 7.76-7.89 (m, 4H) 11.29-11.63 (m, 2H). LC (Cond'n 5): RT=2.49 min; MS: Anal. Calcd. for [M+H]+ C37H46N6O4: 639.4. found 639.9. Step e: 2-((S)-2-methylpyrrolidin-2-yl)-5-(4′-(2-((S)-pyrrolidin-2-yl)-1H-imidazol-5-yl)biphenyl-4-yl)-1H-imidazole (intermediate LS35) was prepared in a similar fashion to the preparation of 1e employing intermediate LS34 in place of 1d. 1H NMR (500 MHz, DMSO-d6) δ ppm 1.76-1.83 (m, 3H) 1.92-2.23 (m, 6H) 3.31-3.49 (m, 4H) 4.88-4.97 (m, 1H) 7.76-7.88 (m, 5H) 7.90-8.04 (m, 5H) 9.72-9.82 (m, 1H) 10.04-10.16 (m, 1H); imidazole and pyrrolidine NH protons unaccounted for. LC (Cond'n 5): RT=1.79 min; MS: Anal. Calcd. for [M+H]+ C27H30N6: 439.2. found 439.5. Step f: Compound LS36 was prepared in a similar fashion to the preparation of example 1 employing intermediate LS35 in place of 1e and Cap-51 in place of Cap-1. 1H NMR (500 MHz, DMSO-d6) δ ppm 0.72-0.97 (m, 12H) 1.77 (s, 3H) 1.86-2.08 (m, 8H) 2.09-2.19 (m, 2H) 2.25-2.39 (m, 2H) 3.49-3.59 (m, 6H) 3.81 (d, J=6.71 Hz, 4H) 4.06 (q, J=7.83 Hz, 2H) 5.08 (dd, J=7.02, 3.05 Hz, 1H) 7.12 (d, J=8.85 Hz, 1H) 7.27-7.34 (m, 1H) 7.46-7.55 (m, 1H) 7.59-7.73 (m, 4H) 7.75-7.86 (m, 3H) 11.66 (s, 1H) 11.77 (s, 1H). LC (Cond'n 5): RT=2.25 min; MS: Anal. Calcd. for [M+H]+ C41H52N8O6: 753.4. found 754.0.

1. concentrationThe reaction mixture was concentrated via a nitrogen stream overnite
2. washThe resultant residue was washed with hexane
3. washThe cartridge was washed with two column lengths of methanol and product
4. washwas eluted with ammonia/methanol
5. concentrationConcentration