Improved process for the preparation of copolymer-1

摘要

The presently disclosed subject matter provides a novel method for preparing copolymer- 1. In one embodiment, a mixture of N-carboxyanhydrides (NCAs) comprising alanine, protected-glutamic acid, protected lysine, and tyrosine, and wherein glutamic acid includes a benzyl or methoxy protecting group and lysine includes a cyclic imide or Boc protecting group are treated with a polymerization initiator to initiate polymerization of the mixture of N-carboxyanhydrides and to thereby synthesize a protected copolymer- 1. The protected copolymer- 1 can then be treated with deprotecting groups and/or depolymerized to obtain a copolymer- 1 having a desired molecular weight.