N-Fmoc-protected(alpha-dipeptidoyl)benzotriazoles for efficient solid-phase peptide synthesis by segment condensation

Abstract

N-Fmoc-protected(alpha-aminoacyl)benzotriazoles 1a-d readily afford chiral N-Fmoc-protected-alpha-dipeptides 2a-f (77-89%). Compounds 2a-f are further converted into N-Fmoc-protected(alpha-dipeptidoyl)benzotriazoles 3a-f (71% average yield). Under mild microwave irradiation, 3a-f are used in solid-phase peptide segment condensation syntheses to give tri-, tetra-, penta-, hexa-, and heptapeptides (20-68%).