PROCESS FOR PREPARING A B30-THREONINE INSULIN

摘要

A process for preparing a B30-threonine-insulin is described which comprises reacting a des-B30-insulin with an excess amount of a threonine derivative represented by the formula Thr(R<1>)(R<2>) wherein Thr is L-threonine residue, R<1> is hydrogen or a hydroxy-protecting group; and R<2> is a carboxyl-protecting group, in the presence of an enzyme specifically acting on the basic-amino-acid carbonyl in peptide linkages.