Patent ID: 7230110

Claim:
A compound represented by formula (I): wherein, in formula (I), R represents -L 1 -X 1 or X 1 ; R 2 represents a hydrogen atom or -L 2 -X 2 ; L 1 and L 2 each independently represent a divalent linking group selected from the group consisting of an alkylene group, an alkenylene group, an alkynylene group, an arylene group, —O—, —S—, —NR—, —COO—, —NRCO—, —SO 2 -. and combinations of two or more of these divalent groups, wherein R represents a hydrogen atom or a substituent selected from the group consisting of alkyl group, an aralkyl group, an alkenyl group, an alkynyl group, a hydroxyalkyl group, an aryl group, a carbonyl group, an acyl group, an alkoxycarbonyl group, and an acyloxy group and wherein when L 1 or L 2 is the combination of an alkylene group and —NR—, R may bond to the alkylene group to form a ring; X 1 and X 2 each independently represent a group selected from the group consisting a hydroxyl group, an amino group and a mercapto group; n represents an integer of 1 to 4; and when n is 2 or more, R 1 s may be the same or different.