Abstract
In order to investigate the reactivity of the side chains of a poly-peptide in a helicogenic solvent, poly(γ-benzyl-L-glutamate) (PBLG) was debenzylated in benzene with anhydrous hydrogen bromide, and the results were compared with those of the debenzylation reaction of benzyl n-butyrate as a model compound. The debenzylation reaction constant of PBLG assuming second-order reaction kinetics was a function of the degree of debenzylation and by extrapolation the initial rate constant was obtained. The debenzylation of benzyl n-butyrate obeyed second-order reaction kinetics. The initial rate constant for PBLG was much smaller than for the model compound and the entropy of activation much greater. The rate of debenzylation of PBLG accelerated with increasing debenzylation on account of the steric effect of the nearest-neighboring side chains distributed in the α-helical backbone chain.
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Nakajima, A., Yasuda, T. Debenzylation Reaction of Poly(γ-benzyl-L-glutamate) in Helicogenic Solvent. Polym J 8, 541–548 (1976). https://doi.org/10.1295/polymj.8.541
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DOI: https://doi.org/10.1295/polymj.8.541