Synthesis of O‐(α‐Glyco)peptides by the N‐Iodosuccinimide Procedure

The glycosylation of serine or threonine in (protected) peptides can be accomplished by reaction with glycals and N‐iodosuccinimide. The 2‐iodo derivatives are obtained in high yields and with high diastereoselectivity. These derivatives can be converted into 2‐deoxy‐α‐glycopeptides of the type 1 (R¹, R²  H, OAc; R³  H, Me; X, Y  protecting groups, amino acid derivatives, or peptide derivatives). (Figure Presented.)