Protein or polypeptide, process for producing the same, and intermediate compound tehrefor

摘要

The present invention provides a protein or polypeptide substance having at least one amino group bonded to a polyethyleneglycolosy group represented by the following general formula; R1 -(OCH2 CH2) n - O - (wherein R1 represents an optionally substituted cholesteryl group; and n represents a positive integer which is arbitrarily variable), and a method for producing said the protein or polypeptide. The present invention also provides a reactive polyethyleneglycol derivative as an intermediated for above the method. The chemically modified protein or polypeptide of the present invention never impairs bonding with a receptor and has a high plysiological activity. Then, a behaviors in vivo of these substance is improved. Now medical substances or drugs having a high pharmacological activity can be developed by using these substance.