Synthesis and conformational properties of poly(N4‐1‐phenylethyl‐L‐asparagines)

摘要

AbstractPoly(N4‐1‐phenylethyl‐L‐asparagines) (1a, 1b, and1c) containing DL‐, (R)‐, and (S)‐ side group chirality were prepared by aminolysis of poly(β‐methyl‐L‐aspartate) (PMLA) with DL‐, (R)‐ (+)‐, and (S)‐ (−)‐1‐phenylethylamine, respectively. The PMLA was synthesized by ring‐opening polymerization of β‐methyl‐L‐aspartate‐N‐carboxy anhydride (NCA) using triethylamine as initiator. The conformations of these polypeptides in the film state were investigated by IR and circular dichroic spectra. The PMLA,1a, and1bexist mainly in β‐sheet conformation, while1cforms α‐helix that is induced by the (S)‐ch