The present invention is concerned with substituted imidazo[1,5-a][1,2,4]triazolo[1,5-d][1,4]benzodiazepine derivatives of formula I wherein R1 is hydrogen, halogen, lower alkyl, lower alkynyl, cycloalkyl, heterocycloalkyl, benzyl, cyano, lower alkoxy, OCF3, -NHR, -NHC(O)R or -NHSO2R； R2 is lower alkyl substituted by halogen； R3 is hydrogen, methyl or aryl； R is lower alkyl, cycloalkyl or aryl； and pharmaceutically acceptable acid addition salts thereof.
