JPH0132222B

A piperazine derivative of the formula:wherein R1 is hydrogen, alkyl (C1-8), alkyl (C1-4)-sulfonyl or an acyl group of the formula: R3CO- (wherein R' is hydrogen, alkyl (C1-7), halogenoalkyl (C1-4), alkoxy (C1-4)-carbonyl- alkyl(C1-4), cycloalkyl (C3-6), alkenyl (C2-5), alkoxy(C1-4), amino, alkyl (C1-4)-amino or anilino), R2 is hydrogen, alkyl (C1-4), alkoxy (C1-4)-carbonyl-alkyl(C1-4), carboxy-alkyl (C1-4), alkenyl (C2-5) or alkyl (Cl-4)-sulfonyl, or R1 and R2 are combined together to form succinyl group, Ring A is phenyl, alkyl (C1- 4)-phenyl or halogenophenyl, and n is an integer of2 2 to 6, or a pharmaceutically acceptable acid addition salt thereof. The piperazine derivative (l) has an intracranial pressure-lowering activity. Said derivative also has a depressing effect on central nervous system.