Synthesis and central nervous system effects of 8.9-dihydro(1)benzazepino(3,2.1-ak)(1,4)benzodiazepin-1(2H)-ones and (1) binzazepino(3,2,1-jk)(1,4)benzodiazepin-1(2H)-ones.

A series of 4-alkyl-8,9-dihydro[1]benzazepino[3,2,1-jk][1,4]benzodiazepin-1(2H)-ones and brominated derivatives was synthesized. Two approaches for the synthesis of 4-alkyl[1]benzazepino[3,2,1-jk][1,4]benzodiazepin-1(2H)-ones and brominated derivatives are described. All compounds were evaluated for CNS activity. None showed significant activity. The results obtained indicate that in the case of the 1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one a phenyl group at the 1 position causes a fall in CNS activity not only when it is free but also when fused to the benzodiazepine system.