Piperazine derivatives and salts thereof.

摘要

PCT No. PCT/JP94/01071 Sec. 371 Date Mar. 10, 1995 Sec. 102(e) Date Mar. 10, 1995 PCT Filed Jul. 1, 1994 PCT Pub. No. WO95/02593 PCT Pub. Date Jan. 26, 1995Piperazine compounds and salts thereof having inhibitory effect against superoxide radicals (O2-). The piperazine compounds have the general formula: wherein R1 is a lower alkyl group; R2 is a phenyl-lower alkyl group which may have 1 to 3 substituents, on the phenyl ring, selected from the group consisting of a hydroxyl group, a phenyl-lower alkoxy group, a lower alkyl group, a lower alkoxy group and a halogen atom; R3 is a hydrogen atom, a lower alkyl group or a phenyl-lower alkyl group; and R4 is a hydroxyl group, a phenyl-lower alkoxy group or a tetrahydropyranyloxy group.