Patent ID: 8703878
Filing Date: 2014-04-22
Classification: A61K,A61P

Abstract:
1. A high-molecular weight conjugate of steroids, comprising a structure in which a carboxylic acid group of a block copolymer having a polyethylene glycol moiety and polyaspartic acid is ester-bonded to an alcoholic hydroxy group in the steroids, and wherein the conjugate is represented by formula (I) wherein R1 represents a (C1-C6) alkyl group; R2 represents a (C2-C6) alkylene group; R3 represents a (C1-C6) acyl group; R4 represents an alcoholic hydroxy group of said steroids; R5 represents a group selected from the group consisting of a (C1-C30) alkoxy group, a (C7-C30) aralkyloxy group, a (C1-C30) alkylamino group, a di(C1-C30) alkylamino group, an amino acid with a protected carboxy group and —N(R6)CONH(R7) wherein R6 and R7, which may be identical or different from each other, represent a (C3-C6) cyclic alkyl group or a (C1-C5) alkyl group which may be substituted with a tertiary amine group; t represents an integer from 100 to 300; and d, e, f, g, h, i or j each independently represents an integer from 0 to 100; provided that d+e represents an integer from 1 to 100, d+e+f+g+h+i+j represents an integer from 6 to 100; and respective units of the polyaspartic acid are bonded in any order.