N-substituted trialkoxybenzyl piperazine derivatives

N-substituted trialkoxybenzyl piperazine derivatives expressed by the following general formula (I): (I) where R represents a methyl or ethyl group, and Z represents a group selected from the group consisting of the following groups: isopropenyl group, cinnamyl group, morpholino ethyl group, diaminotriazine group, hydantoinbutyl group, where R represents the same as above, and n is an integer of 2 to 8, and where A represents a group selected from the group consisting of hydrogen, lower alkyl group, hydroxymethyl group, phenyl group, naphthyloxymethyl group and where Y represents a group selected from the group consisting of hydrogen, halogen, lower alkyl group, lower alkoxy group and hydroxy group.