| abstract |
The object of the present invention is to find a carotenoid compound that is excellent in water solubility. A carotenoid derivative having a formula (I): wherein X represents a carbonyl group or a methylene group, one of R1 and R2 represents (a) or (b) and the other represents (a), (b), (c) or a hydrogen atom: (a): -CO-A-B-D wherein A represents an alkylene group an alkenylene group, etc., B represents a formula of -S(O)n- or a formula of -NR4CONR5- and D represents a hydrogen atom, a carboxyl group, etc., (b): -CO-E-F wherein E represents an alkylene group or a formula of -NR3- wherein R3 represents (a1) a hydrogen atom, (b1) an alkyl group, etc., and F represents a sulfo group and c): -CO-G wherein G represents a hydrogen atom, an alkyl group, etc., a pharmaceutically acceptable salt thereof, or a pharmaceutically acceptable ester or amide thereof. |