Dicyclohexylcarbodiimide → (3RS)-1,3-dihydro-3-(2-indolylcarbonylamino)-5-phenyl-1-{2-((RS)-2-tetrahydropyranyloxy)ethyl}-2H-1,4-benzodiazepine-2-one

Participants

Reaction Steps

To a mixture of indole-2-carboxylic acid (0.19 g), N-hydroxybenzotriazole (0.16 g) and N,N'-dicyclohexylcarbodiimide (0.24 g) in chloroform (10 ml) was added a mixture (0.43 g) of (3RS)-1,3-dihydro-5-phenyl-3-amino-1-{2-((RS)-2-tetrahydropyranyloxy) ethyl }-2H-1,4-benzodiazepine-2-one and (3RS)-1,3-dihydro-5-phenyl-3-amino-1-{2-((SR)-2-tetrahydropyranyloxy) ethyl }-2H-1,4-benzodiazepine-2-one at ambient temperature under stirring. The mixture was stirred for 2 hours under the same conditions. The resultant precipitate was filtered off. The combined filtrate and washings were evaporated under reduced pressure and the residual oil (1.20 g) was subjected to column chromatography on silica gel with an eluent of a mixture of chloroform and ethyl acetate (10:1) to give a mixture (white powder, 0.45 g) of (3RS)-1,3-dihydro-3-(2-indolylcarbonylamino)-5-phenyl-1-{2-((RS)-2-tetrahydropyranyloxy)ethyl}-2H-1,4-benzodiazepine-2-one and (3RS)-1,3-dihydro-3-(2 -indolylcarbonylamino )-5-phenyl-1-{2-((SR)-2-tetrahydropyranyloxy) ethyl}-2H-1,4-benzodiazepine-2-one.

Provenance & Evidence