Synthesis Of N-substituted Amino Acids And Polypeptoids Via Schiff Base Reactions

Polypeptides show similar chemical structure to proteins.They are linked by amide bonds and can be assigned specific function by side chain modification.Due to the substitution of nitrogen atoms,polypeptoids have emerging as a promising biological material with reduced hydrogen bonding.However,due to the limitation of current synthetic methods,the introduction of functional groups is difficult.In this paper we used amino acid and benzaldehyde derivatives to obtain Nsubstituted amino acids by Schiff base-reduction reaction.They can be synthesized into peptoid oligomers and diblock copolymers by NCA cyclization and ring-opening reactions.Both the homopolymers and diblock copolymers show good crystalline property..We also studied the self-assembly and gel properties of them and we found that the oligopeptoids with hydrophilic side group had better solubility than the oligopeptoids with hydrophobic side group which had cancer cell toxicity to some degree and temperature sensitivity characteristics.In short,the facile method can utilize abundant raw materials to obtain Nsubstituted ?-amino acids with high purity and high yield for further polymerization.And some of polypeptoids has interesting properties.We create a new synthetic route and offer a certain contribution to development of polypeptide-based materials.