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Stepwise synthesis of oligopeptides with N-carboxy α-amino acid anhydrides

✍ Scribed by Oshio Iwakura; Keikichi Uno; Masanao Oya; Ryoichi Katakai

Publisher
Wiley (John Wiley & Sons)
Year
1970
Tongue
English
Weight
365 KB
Volume
9
Category
Article
ISSN
0006-3525

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✦ Synopsis

Abstract

Oligopeptides were synthesized in high yields by the controlled coupling reaction of N‐carboxy α‐amino acid anhydrides (NCA's) with amino acid and peptide sodium salts in the heterogeneous reaction medium of acetonitrile–water which contained sodium carbonate. In this solvent, it could be considered that the reaction could occur at the interface of acetonitrile and aqueous layers, and that NCA's could be protected by the organic layer from side reactions such as hydrolysis and polymerization. The careful control of reaction conditions such as pH of the solution was not necessary when the heterogeneous mixed solvent was used. Sodium carbonate which had not been used for a reaction of this kind could be satisfactorily used for stabilizing the carbamate intermediates in the aqueous layer of the heterogeneous reaction medium.

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