Allophanoylpiperazine compound and analgesic composition containing same as active ingredient

摘要

An analgesic compositon containing as active ingredient an allophanoylpiperazine compound represented by the general formula <IMAGE> wherein R1 represents a lower alkyl group or phenyl group; R2 and R3 each represents a hydrogen atom or a lower alkyl group; and R4 represents a phenyl group or a substituted phenyl group having as substituent a halogen atom or methyl, trifluoromethyl, hydroxyl, methoxy, methylenedioxy, nitro, or carboxyl group; pyridyl group, pyrimidyl group, thiazolyl group, benzyl group, cinnamyl group, cyclohexyl group, a lower alkyl group, a substituted lower alkyl group having chlorine atom or hydroxyl group as substituent; or a lower alkenyl group.