N-(Cbz- and Fmoc-α-aminoacyl)benzotriazoles: Stable derivatives enabling peptide coupling of Tyr, Trp, Cys, Met, and Gln with free amino acids in aqueous media with complete retention of chirality

Article abstract of DOI:10.1055/s-2005-861782

Crystalline, chirally stable N-(Cbz- and Fmoc-α-aminoacyl) benzotriazoles 2a-f, activated derivatives of Tyr, Trp, Cys, Met and Gln undergo peptide coupling in aqueous media with unprotected L-Ala-OH and L-Phe-OH to give the chiral dipeptides in 70-98% yi