Patent ID: 8808749

Claim:
A polymer conjugate of a physiologically active substance, comprising a block copolymer of a polyethylene glycol moiety and a polyglutamic acid moiety, in which a substituent bound to the physiologically active substance is linked to at least one of the side-chain carboxy groups of the block copolymer via an amide bond, and the physiologically active substance is directly bonded to the side-chain carboxy groups of the block copolymer, wherein the polymer conjugate is a compound represented by general formula (III) wherein R 1 represents hydrogen atom or (C1-C6)alkyl group, R 2 represents a linking group, R 3 represents hydrogen atom or (C1-C6)acyl group, R 4 represents a substituent represented by general formula (I) or general formula (II) in which R 8 and R 9 each independently represent a hydrogen atom or (C1-C6)alkyl group which may optionally have a substituent, R 10 represents hydrogen atom, (C1-C40)alkyl group which may optionally have a substituent, (C1-C40)aralkyl group which may optionally have a substituent, an aromatic group which may optionally have a substituent, an amino acid residue having a protected carboxy group, or a sugar residue which may optionally have a substituent, CX—CY represents CH—CH or C═C (double bond), and A represents a residue obtained by removing, from the physiologically active substance having one or more hydroxy groups, one of the one or more hydroxy groups, R 5 represents a substituent represented by general formula (IV) or general formula (V) in which R 8 , R 9 , R 10 , and CX—CY have the same meanings as above, R 11 represents one or more substituents selected from a group consisting of hydroxy group, an aromatic amino group which may optionally have a substituent, (C1-C30)alkoxy group which may optionally have a substituent, (C1-C30)aralkyloxy group which may optionally have a substituent, (C1-C30)alkylamino group which may optionally have a substituent, di(C1-C30)alkylamino group which may optionally have a substituent, an amino acid having a protected carboxy group, and NR 12 CONHR 13 , wherein R 12 and R 13 , which may be the same or different from each other, represent (C3-C6)cyclic alkyl group, or (C1-C5)alkyl group which may optionally be substituted with a tertiary amino group, R 6 represents a substituent represented by general formula (VI) in which R 8 , R 9 , R 10 , and CX—CY have the same meanings as above, R 7 represents a substituent selected from a group consisting of (C1-C30)alkoxy group, (C1-C30)aralkyloxy group, (C1-C30)alkylamino group, di(C1-C30)alkylamino group, an amino acid having a protected carboxy group, and NR 12 CONHR 13 , wherein R 12 and R 13 , which may be the same or different from each other, represent (C3-C6)cyclic alkyl group, or (C1-C5)alkyl group which may optionally be substituted with a tertiary amino group, b is an integer from 5 to 11,500, i is an integer from 1 to 200, j, k, m, and n each represent an integer from 0 to 200 with the proviso that i+j+k+m+n represents an integer from 2 to 200.