O-Methyl-Oμ-[(N-succinimidyl)succinyl-aminoethyl]polyethylene glycol 2μ000, O-Methyl-Oμ-[2-(succinylamino)-ethyl]polyethylene glycol 2μ000 N-succinimidyl ester | O-Methyl-Oμ-[(N-succinimidyl)succinyl-aminoethyl]polyethylene glycol 5μ000, O-Methyl-Oμ-[2-(succinylamino)-ethyl]polyethylene glycol 5μ000 N-succinimidyl ester |