Abstract The cyclocondensation of (dimethylamino) benzodiazepinones 3a, b with hydrazides yielded triazolobenzodiazepinones 4 which were treated with Lawesson's reagent to give thiolactams 5. The phase-transfer catalyzed (TEBA) alkylation of compounds 5 with suitable alkyl halides afforded 5-(alkylthio)-6-phenyl-6H-[1, 2, 4] triazolo [4, 3-a][1, 5] benzodiazepines 6a-f. The desired N, N-dialkyl-6-phenyl-6H-[1, 2, 4] triazolo [4, 3-a][1, 5] ...