| abstract |
To provide a high molecular weight polyethylene glycol derivative that does not cause vacuolation of cells. The following formula (1): (In the formula, m is 1 to 7, n1 and n2 are each independently 45 to 682, p is 1 to 4, R is an alkyl group having 1 to 4 carbon atoms, and Z is cysteine. Is an oligopeptide having 2 to 8 residues consisting of neutral amino acids except Q, Q is a residue of a compound having 2 to 5 active hydrogens, X is a functional group capable of reacting with a biological substance, L 1 , L 2 , L 3 , L 4 and L 5 are each independently a single bond or a divalent spacer.) Degradable polyethylene glycol derivatives represented by [Selection figure] None |