HETERO-BIFUNCTIONAL POLYETHYLENE GLYCOL DERIVATIVE AND METHOD FOR PREPARING IT

摘要

PROBLEM TO BE SOLVED: To provide a method for preparing a hetero-bifunctional derivative of poly(ethylene glycol) or a related polymer thereof with a high purity and in a high yield. SOLUTION: An intermediate polymer of the formula: W-poly-OH is provided with a removable group W at one terminus without going through a chromatographic purification step. The intermediate polymer W-poly-OH is first modified by converting the OH group into a first functional group X and subsequently removing W to produce a second hydroxyl group. Then, the latter hydroxyl group is converted into a second functional group Y to obtain the desired hetero-bifunctional derivative. COPYRIGHT: (C)2008,JPO&INPIT