Abstract
The conformational behavior of random copolypeptides of γ-benzyl L-glutamate and γ-methyl L-glutamate was studied by nuclear magnetic resonance in deuterated chloroform—trifluoroacetic acid under various conditions of solvent composition and temperature. The results show that the helix stability of the copolymers is intermediate between those of the two homopolymers, poly(γ-benzyl L-glutamate) and poly (γ-methyl L-glutamate). Broadening and upfield shift are observed for the CH3 proton resonance of the γ-methyl L-glutamate residue of the copolymers. These are attributed to the ring current effect of the phenyl rings on the CH3 protons. The triad sequence of γ-benzyl L-glutamate and γ-methyl L-glutamate in the copolymers was estimated from the CH3 resonance.
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Hiraoki, T., Tsutsumi, A., Hikichi, K. et al. Proton Nuclear Magnetic Resonance of Random Copoly(γ-benzyl L-glutamate, γ-methyl L-glutamate). Polym J 8, 429–435 (1976). https://doi.org/10.1295/polymj.8.429
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DOI: https://doi.org/10.1295/polymj.8.429