Reaction Steps
To the solution of 2-[5-(4-Bromo-3-methoxycarbonyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester (200 mg, 0.44 mmol) in THF (4 ml) at −78° C. was added DIBAL-H THF solution (3.33 ml, 3.33 mmol). The mixture was warmed to 25° C. and stirred for 5 hours. The mixture was cooled to 0° C. and quenched with 2.0 N NaOH solution until PH=11. The mixture was extracted with EtOAc. The organic phase was washed with water and brine, and was dried with sodium sulfate. Concentration gave 2-[5-(4-bromo-3-hydroxymethyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester (196 mg). m/z: 421.9 (M+H)+, 420.2 (M−H)−. 2-[5-(4-Bromo-3-formyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester: To the solution of 2-[5-(4-bromo-3-hydroxymethyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester (196 mg, 0.46 mmol) in DMSO (3.5 ml) was added triethylamine (0.40 ml). The mixture was stirred for 30 minutes, and pyridine-sulfur trioxide (500 mg) was added. The mixture was stirred for 2 hours and was quenched with ice-water. The stirring was continued for additional 30 minutes and the mixture was extracted with EtOAc. The organic phase was washed with water and brine, and was dried with sodium sulfate. Concentration gave 2-[5-(4-Bromo-3-formyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester (180 mg). 2-(5-{4-Bromo-3-[(tert-butoxycarbonyl-methyl-amino)-methyl]-phenyl}-1H-imidazol-2-yl)-pyrrolidine-1-carboxylic acid tert-butyl ester: To the solution of 2-[5-(4-bromo-3-formyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester (180 mg, 0.46 mmol) in MeOH/THF (2.5 ml/2.5 ml) was added methylamine methanol solution (0.69 ml, 1.38 mmol), followed by acetic acid (110 μl, 1.84 mmol) and NaBH(OAc)3 (975 mg, 4.6 mmol). The mixture was stirred for 12 hours and was quenched with 1 N sodium hydroxide solution. The mixture was extracted with EtOAc. The organic phase was washed with water and brine, and was dried with sodium sulfate. Concentration gave the intermediate (171 mg). To the solution of the above intermediate (171 mg, 0.39 mmol) in DCM (4 ml) was added di-tert-butyl dicarbonate (86 mg, 0.39 mmol), followed by diisopropylethylamine (135 6l, 0.78 mmol). The mixture was stirred for 12 hours, and the solvent and reagent was evaporated. Purification by flash column chromatography (hexanes/EtOAc) gave 2-(5-{4-bromo-3-[(tert-butoxycarbonyl-methyl-amino)-methyl]-phenyl}-1H-imidazol-2-yl)-pyrrolidine-1-carboxylic acid tert-butyl ester (142 mg). m/z: 535 (M+H)+. 4,4′-Bis-[2-(1-tert-butoxycarbonyl-pyrrolidin-2-yl)-3H-imidazol-4-yl]-biphenyl-2-Ktert-butoxycarbonyl-methyl-amino)-2′-carboxylic acid dimethyl ester: To the solution of 245-{4-bromo-3-Rtert-butoxycarbonyl-methyl-amino)-methyl]-phenyl}-1H-imidazol-2-yl)-pyrrolidine-1-carboxylic acid tert-butyl ester (142 mg, 0.27 mmol) and 2-{5-[3-Methoxycarbonyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-1H-imidazol-2-yl}-pyrrolidine-1-carboxylic acid tert-butyl ester (125 mg, 0.25 mmol) in 1,2-dimethoxyether (2.3 ml) and water (0.7 ml) was added sodium bicarbonate (63 mg, 0.75 mmol), followed by Pd(PPh3)4 (12 mg) and PdCl2(dppf)CH2Cl2 (12 mg). The mixture was heated at 80° C. for 20 hours. The mixture was diluted with EtOAc, and was washed with water and brine, and was dried with sodium sulfate. Concentration and purification by flash column chromatography (hexanes/EtOAc) gave 4,4′-bis-[2-(1-tert-butoxycarbonyl-pyrrolidin-2-yl)-3H-imidazol-4-yl]-biphenyl-2-[(tert-butoxycarbonyl-methyl-amino)-2′-carboxylic acid dimethyl ester (82 mg). m/z: 826 (M+H)+, 413.6 (M+2H)+/2. 2′-Methylaminomethyl-4,4′-bis-(2-pyrrolidin-2-yl-3H-imidazol-4-yl)-biphenyl-2-carboxylic acid methyl ester: To the solution of 4,4′-bis-[2-(1-tert-butoxycarbonyl-pyrrolidin-2-yl)-3H-imidazol-4-yl]-biphenyl-2-Rtert-butoxycarbonyl-methyl-amino)-2′-carboxylic acid dimethyl ester (77 mg, 0.09 mmol) in DCM (3 ml) was added trifluoroacetic acid (3 ml). The mixture was stirred for 2 hours, and the solvent and reagent were removed under reduced pressure. The mixture was diluted with acetonitrile and water, was freezer-dried to give 2′-methylaminomethyl-4,4′-bis-(2-pyrrolidin-2-yl-3H-imidazol-4-yl)-biphenyl-2-carboxylic acid methyl ester as white powder (90 mg). m/z: 526.1 (M+H)+. 6-Methyl-3,9-bis-(2-pyrrolidin-2-yl-3H-imidazol-4-yl)-6,7-dihydro-dibenzo[c,e]azepin-5-one: To the solution of 2′-methylaminomethyl-4,4′-bis-(2-pyrrolidin-2-yl-3H-imidazol-4-yl)-biphenyl-2-carboxylic acid methyl ester (90 mg) in pyridine (5 ml) was added diisopropylethylamine (1 ml). The mixture was heated at 100° C. for 2 hours. The solvents were evaporated. The mixture was diluted with acetonitrile and water, was freezer-dried to give 6-Methyl-3,9-bis-(2-pyrrolidin-2-yl-3H-imidazol-4-yl)-6,7-dihydro-dibenzo[c,e]azepin-5-one as brown powder. m/z: 494.1 (M+H)+. (1-{2-[5-(9-{2-[1-(2-Methoxycarbonylamino-3-methyl-butyryl)-pyrrolidin-2-yl]-3H-imidazol-4-yl}-6-methyl-5-oxo-6,7-dihydro-5H-dibenzo[c,e]azepin-3-yl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester: To the solution of 6-methyl-3,9-bis-(2-pyrrolidin-2-yl-3H-imidazol-4-yl)-6,7-dihydro-dibenzo[c,e]azepin-5-one (0.09 mmol) and MeOCO-Val-OH (33 mg, 0.19 mmol) in DMF (3 ml) was added HATU (71 mg, 0.19 mmol), followed by diisopropylethylamine (323 μl , 1.86 mmol). The mixture was stirred for 60 minutes and was diluted with EtOAc. The organic phase was washed with 1 N NaOH solution, water, and brine, and was dried with sodium sulfate. Concentration and purification by HPLC (0.1% TFA/CH3CN/0.1% TFA/H2O) gave (1-{2-[5-(9-{2-[1-(2-Methoxycarbonylamino-3-methyl-butyryl)-pyrrolidin-2-yl]-3H-imidazol-4-yl}-6-methyl-5-oxo-6,7-dihydro-5H-dibenzo[c,e]azepin-3-yl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester (16 mg). m/z: 808.2 (M+1), 404.8 (M+2)/2, 806.3 (M−1). 1H NMR (CD3OD, 300 MHz) δ 8.1-7.8 (8H, m), 5.4-5.2 (2H, m), 4.6-4.2 (4H, m), 4.2-4.0 (2 H, m), 3.95-3.80 (2H, m), 3.64 (6H, m), 3.25 (3H, s), 2.65-2.45 (2H, m), 2.35-2.0 (8H, m), 1.05-0.9 (12H, m).
