Triphosgene was used to react with γ-chloroethyl glutamate, which was synthesized from 2-ethylene chlorohydrin and L-glutamic acid, to give γ-chloroethyl glutamate N-carboxyan.hydride (NCA). Thus, poly(γ-chloroethyl glutamate), a new poly (amino acid) with reactive chloride, was obtained from the NCA by using triethylamine as the initiator which can lead to intrinsic viscosity of polypeptide, [η], over 50 mL/g. NCA and polymer were characterized by IR, 1H NMR and 13C NMR. Oligomer of γ-chloroethyl glutamate was also obtained while NCA was initiated by moisture in air. The conforma- tions of oligomer and polymer of γ-chloroethyl glutamate were observed by IR and CD spectroscopy. The results suggested that the conformation of oligomer mainly be β-sheet, while the polymer be α-helix.
