Carbostyril derivatives and their salts

Claim 1

A arbostyril derivative or a pharmaceutically acceptable salt thereof said derivative being represented by the formula (1), ##STR30## wherein R 1 is a hydrogen atom, a lower alkyl group, a lower alkenyl group, a lower alkynyl group or a phenyl-lower lower alkyl group; R 2 and R 3 may form, together with the adjacent nitrogen atom and further with an additional nitrogen atom, a 6-membered saturated heterocyclic ring which may have a lower alkyl group or a phenyl-lower alkyl group as the substituent; when said heterocyclic ring is a piperazinyl group, said piperazinyl ring may have a lower alkyl group or a phenyl-lower alkyl group as the substituent at 4-position in the piperazinyl ring, further said piperazinyl group may have, as the substituent at 4-position, a lower alkenyl group, a lower alkynyl group, a cycloalkyl group, a cycloalkyl-lower alkyl group, a lower alkanoyl group, a lower alkanoyl-lower alkyl group, a lower alkoxycarbonyl group, a lower alkoxycarbonyl-lower alkyl group, a furoyl group, a lower alkylsulfonyl group, a substituted lower alkyl group (having one substituent selected from the group consisting of a cyano group, a benzoyloxy group (which may have 1 to 3 lower alkoxy groups on the phenyl ring), a hydroxy group, a lower alkanoyloxy group, a halogen atom and a carbamoyl group), a phenoxy-lower alkyl group (which may have, on the phenyl ring, 1 to 3 substituents selected from the group consisting of a halogen atom, a lower alkoxy group and a lower alkyl group, or said phenoxy-lower alkyl group may have, on the phenyl ring, a lower alkylenedioxy group as the substituent), a phenyl-lower alkyl group (which may have, on the phenyl ring, 1 to 3 substituents selected from the group consisting of a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group, an amino group, a lower alkanoylamino group and a lower alkylthio group, or said phenyl-lower alkyl group may have, on the phenyl ring, a lower alkylenedioxy group as the substituent), a benzoyl group (which may have, on the phenyl ring, 1 to 3 substituents selected from the group consisting of a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group and a cyano group, or said benzoyl group may have, on the phenyl ring, a lower alkylenedioxy group as the substituent), a phenyl-sulfonyl group (which may have, on the phenyl ring, 1 to 3 lower alkyl groups as the substituents), a benzoyl-lower alkyl group (which may have, on the phenyl ring, 1 to 3 substituents selected from the group consisting of a halogen atom, a hydroxy group, a lower alkyl group, a lower alkoxy group and a lower alkanoylamino group), a phenyl-lower alkenyl-carbonyl group (which may have, on the phenyl ring, 1 to 3 substituents selected from the group consisting of a halogen atom and a lower alkoxy group), or a phenyl-lower alkanoyl group (which may have, on the phenyl ring, 1 to 3 lower alkoxy groups as the substitutents); the carbon-carbon bond between 3- and 4-positions in the carbostyril skeleton being a single or double bond.