Patent ID: 7871464

Claim:
An anthrapyridone compound represented by the following formula (1) or a salt thereof: wherein, n represents an integer number of 1 to 3, R 1 represents a hydrogen atom, an alkyl group, a hydroxy lower alkyl group, a cyclohexyl group, a mono- or di-alkylaminoalkyl group, or a cyano lower alkyl group, R 2 represents a hydrogen atom or a methoxy group, and R 3 represents an unsubstituted anilino group or an anilino group having, as a substituent, at least one group selected from the group consisting of a sulfo group, a carboxy group, an alkoxy group, a carbamoyl group, a cyano group, an alkyl group, an anilino group, a phenoxy group, an amino group, a hydroxy group and a mercapto group; an unsubstituted mono- or di-alkylamino group or a mono- or di-alkylamino group having, as substituent, at least one group selected from the group consisting of a sulfo group, a carboxy group, an alkoxy group, a carbonyl group, a carbamoyl group, a cyano group, an anilino group, a phenoxy group, an amino group, a monoalkylamino group, a dialkylamino group, a hydroxy group, a mercapto group and a phenyl group; an unsubstituted phenylthio group or a phenylthio group having, as a substituent, at least one group selected from the group consisting of a sulfo group, a carboxy group, an alkoxy group, a carbonyl group, a carbamoyl group, a cyano group, an alkyl group, an anilino group, a phenoxy group, an amino group, a hydroxy group and a mercapto group; an unsubstituted alkylthio group or an alkylthio group having, as a substituent, at least one group selected from the group consisting of a sulfo group, a carboxy group, an alkoxy group, a carbonyl group, a carbamoyl group, a cyano group, an anilino group, a phenoxy group, an amino group, a hydroxy group, a mercapto group and a phenyl group; a naphthylamino group substituted by a sulfo group or an unsubstituted naphthylamino group; an unsubstituted phenoxy group or a phenoxy group having, as a substituent, at least one group selected from the group consisting of a sulfo group, a carboxy group, an acetylamino group, an amino group, a hydroxy group, a phenoxy group and a phenyl group; a hydroxy group; a mercapto group; or an unsubstituted amino group; respectively.