Collect. Czech. Chem. Commun. 1983, 48, 1477-1482

Synthesis of two 1-substituted 8-bromo-6-(2-chlorophenyl)-4H-s-triazolo[4,3-a]-1,4-benzodiazepines

Zdeněk Vejdělek and Miroslav Protiva

Research Institute for Pharmacy and Biochemistry, 130 60 Prague 3


2-Amino-5-bromo-2'-chlorobenzophenone (VII) afforded by a reaction with phthalimidoacetyl chloride the phthalimido derivative VIII which was transformed by hydrazinolysis to 7-bromo-5-(2-chlorophenyl)-1,3-dihydro-1,4-benzodiazepin-2-one (II). A reaction with phosphorus pentasulfide in pyridine gave the thiolactam IX which reacted with hydrazides of acetic and methylthioacetic acid in boiling 1-butanol and gave the title compounds V and VI. Compound V is very potent in pharmacological tests for anticonvulsant, central depressant and discoordinating activity in mice; compound VI is somewhat weaker.