PURPOSE: To provide a novel compd. that has analgesic properties and is useful for the inflammations of the joints, etc.

CONSTITUTION: The compd. of formula I (R1 is H, a lower alkyl, lower alkanoyl, etc.; R2 is H, a lower alkyl; R3, R4 are each H, a lower alkyl, halogen up to atomic number 35; R5 is a halogen up toe atomic number 35). for example, 1-[4-(N-propionylamino)benzoyl]-4-[2-(4-chlorophenyl)ethyl]-piperazine. The compd. of the formula I is obtd. by bringing the compd. of formula II into reaction with the compd. of formula III.