2-Aryl-4-(1-piperazinyl)-3H-1,5-benzodiazepines of the formula ##STR1## wherein R is hydrogen, alkyl having from 1 to 7 carbon atoms or phenyl; Ar is phenyl, trifluoromethylphenyl or phenyl substituted with 1 or 2 halogen, alkyl having from 1 to 4 carbon atoms or alkoxy having from 1 to 4 carbon atoms; X and Y are each hydrogen, halogen, alkyl having from 1 to 4 carbon atoms or alkoxy having from 1 to 4 carbon atoms; and the dotted line represents a single bond wherein hydrogen is attached to N or a double bond. These compounds are useful as muscle relaxants.