Synthesis of Aib-Pro Oligopeptides by repeated Azirine coupling with the Aib-Pro synthon

Abstract

A new synthesis of (Aib-Pro)n oligopeptides (n = 2, 3, and 4) via azirine coupling by using the dipeptide synthon methyl N-(2,2-dimethyl-2H-azirin-3-yl)-l-prolinate (1b; Fig. 1) is presented. The most important feature of the employed protocol is that no activation of the acid component is necessary, i.e., no additional reagents are required, and the coupling reaction is performed under mild conditions at room temperature. As an attempt to provide an answer to the question of the preferred conformation of the prepared molecules, we ca Show more