Patent ID: 7169761

Claim:
An azulene derivative of following formula (I) or a salt thereof: wherein R 1 to R 4 individually represent a hydrogen atom, optionally substituted lower alkyl, —C(═O)-optionally substituted lower alkyl, or —optionally substituted lower alkylene-optionally substituted aryl, R 5 to R 12 individually represent a hydrogen atom, an optionally substituted lower alkyl, halogen atom, —OH, —O-optionally substituted lower alkyl, -optionally substituted lower alkylene-OH, -optionally substituted lower alkylene-O-optionally substituted lower alkyl, —O-optionally substituted lower alkylene-O-optionally substituted lower alkyl, —O-optionally substituted lower alkylene-optionally substituted aryl, -optionally substituted lower alkylene-O—C(═O)-optionally substituted lower alkyl, —COOH, nitro, cyano, amino, substituted amino, or —C(═O)—O-optionally substituted lower alkyl, and A represents a bond or an optionally substituted lower alkylene, wherein -A- may be bonded to any one of the positions 1–8 of the azulene ring, and any two of R 5 , R 6 , and R 7 may form a benzene ring together with the adjacent carbon atoms, and wherein optionally substituted chemical groups are substituted with a haloaen atom, —OH, -lower alkylene-OH, —COOH, —C(═O)—O-lower alkyl, nitro, cyano, or an amino group.