Recent Advances and Future Developments in the Preparation of Polypeptides via N -Carboxyanhydride (NCA) Ring-Opening Polymerization.

Polypeptides have the same or similar backbone structures as proteins and peptides, rendering them as suitable and important biomaterials. Amino acid N -carboxyanhydrides (NCA) ring-opening polymerization has been the most efficient strategy for polypeptide preparation, with continuous advance in the design of initiators, catalysts and reaction conditions. This Perspective first summarizes the recent progress of NCA synthesis and purification. Subsequently, we focus on various initiators for NCA polymerization, catalysts for accelerating polymerization or enhancing the controllability of polymerization, and recent advances in the reaction approach of NCA polymerization. Finally, we discuss future research directions and open challenges.