Hydrogen Sulfide → (S)-8-chloro-9-oxo-12,12a-dihydro-9H,11H-azeto[2,1-c]imidazo[1,5-a][1,4]-benzodiazepine-1-thiocarboxamide

Participants

Reaction Steps

A stream of hydrogen sulphide was conducted for 1 hr. through a solution of 11.3 g (0.0396 mol) of (S)-8-chloro-9-oxo-12,12a-dihydro-9H,11H-azeto[2,1-c]imidazo[1,5-a][1,4]benzodiazepine-1-carbonitrile in 230 ml of pyridine and 2.3 ml of triethylamine. The green solution was left to stand for 48 hrs., then de-gassed with a stream of nitrogen and subsequently completely freed from the solvents. The residue was partitioned between dichloromethane and water and extracted. The pale yellow product was recrystallized in tetrahydrofuran and subsequently in methanol. There were obtained 4.44 g (35%) of (S)-8-chloro-9-oxo-12,12a-dihydro-9H,11H-azeto[2,1-c]imidazo[1,5-a][1,4]benzodiazepine-1-thiocarboxamide as pale yellow crystals; m.p. 250-253° and [α]D20 =-330.6° (DMF, c=1%).

Provenance & Evidence