Oxirane derivative and process for the preparation thereof

The present invention relates to an oxirane derivative and a process for the preparation thereof. More particularly, the present invention relates to a high molecular oxirane derivative having a narrow molecular weight distribution, little impurity content and a high purity useful as a starting material of terminal-modified oxirane derivative for medical purposes, particularly for chemical modification of physiologically active protein such as polypeptide and enzyme and chemical modification in drug delivery system for liposome, polymer micelle, etc., and a process for the preparation thereof. An oxirane derivative and process for preparation of the same, having a high purity characterized in terms of gel permeation chromatography and thin layer chromatography. The oxirane derivative is useful as a starting material for medical purposes, and mainly drug delivery systems.