Pyrazolodiazepines. 2. 4-Aryl-1,3-dialkyl-6,8-dihydropyrazolo[3,4-e] [1,4]diazepin-7(1H)-ones as antianxiety and anticonvulsant agents.

A series of 4-aryl-1,3-dialkyl-6,8-dihydropyrazolo[3,4-e] [1,4]diazepin-7(1H)-ones was synthesized and screened for psychotropic activity. In animals, a number of these pyrazolodiazepinones had strong CNS effects similar to diazepam. One compound, 4-(2-fluorophenyl)-6,8-dihydro-1,3,8-trimethylpyrazolo[3,4-e] [1,4]diazepin-7(1H)-one (54), is being studied in the clinic as a component of a new animal anesthetic, Tilazol.