7-bromo-2-hydrazino-5-(o-chlorophenyl)-3H-1,4-benzodiazepine 、
丙酮酸甲酯 以to give 7-bromo-2-[[1-(methoxycarbonyl)ethylidene]hydrazino]-5-(o-chlorophenyl)-3H-1,4-benzodiazepine的产率得到7-bromo-2-[[1-(methoxycarbonyl)ethylidene]hydrazino]-5-(o-chlorophenyl)-3H-1,4-benzodiazepine