Polymer conjugate of sulfoxide derivative-coordinated platinum(II) complex

A polymer conjugate of a platinum(II) complex, the polymer conjugate comprising:

• a block copolymer having a polyethylene glycol structural moiety and a polyaspartic acid moiety;
• a sulfoxide derivative introduced into a side-chain carboxyl group of the block copolymer;
• and
• a platinum(II) complex coordinate-bonded to a sulfoxide group of the sulfoxide derivative;
• wherein the polymer conjugate is represented by the following General Formula (I):
• wherein R1 represents a methyl group;
• R2 represents a trimethylene group;
• R3 represents an acetyl group;
• R4 represents a substituent selected from the group consisting of substituents represented by the following Formula (V):
• or a substituent selected from the group of substituents represented by the following Formula (VI):
• wherein A1, A2, A3 each represent a ligand of the platinum complex and Z− represents a counter anion;
• at least one of R4 represents a substituent coordinate-bonded to the platinum complex represented by Formula (VI);
• R5 represents a substituent represented by the following General Formula (IV) obtained by eliminating H from an α-amino group of an α-amino acid derivative:
• with a benzyl group as Q, or —NR9CONHR10;
• and R9 and R10 both represent a cyclohexyl group or an isopropyl group;
• a represents an integer from 10 to 2,000;
• d, e, f, g, h, i, and j each represent an integer from 0 to 100;
• d+e represents an integer from 1 to 100;
• d+e+f+g+h+i+j represents an integer from 4 to 100;
• and the order of bonding of the various constituent units of polyaspartic acid is random.