Carbostyril derivatives, method for their preparation and antihistamine agents, CONTAINING THE carbostyril.

摘要

Novel carbostyril derivatives and their salts having antihistaminic effects and are useful as antihistaminic agents, represented by the general formula (1), IMAGE (1) wherein R1 is a hydrogen atom, a lower alkenyl group, a lower alkynyl group or a lower alkyl group which may have phenyl group(s) as the substituted group(s); R2 is a hydrogen atom, a lower alkyl group or a phenyl group; R3 is a lower alkyl group having phenyl group(s) as the substituted group(s), or a phenyl group which may have 1 to 3 substituted groups selected from the group consisting of halogen atoms, lower alkyl groups and lower alkoxy groups; R4 is a hydrogen atom, a hydroxyl group or a lower alkanoyl group; X is a halogen atom; Y is a lower alkylene group which may have hydroxyl group(s) as the substituent(s); n is 0, 1 or 2; the carbon-carbon bond between 3- and 4-positions in the carbostyril skeleton is a single or double bond; provided that when R3 is a lower alkyl group having phenyl group(s) as the substituted group(s), then R4 should be neither a hydroxyl group nor a lower alkanoyl group.