Acylation of Sugar Hydroxyl Groups with N-BOC Amino Acid N-Carboxyanhydrides (Boc-NCAs). Synthesis of Amino Acid-Saccharide Conjugates

Abstract

Boc-NCAs cleanly react with a series of free or protected sugars to give mono-or poly-amino acid conjugates in good yields. Trifluoroacetic acid in methylene chloride only cleaves the N-Boc protecting group. Treatment with aqueous trifluoroacetic acid removes the remaining isopropylidene protecting groups and leads to free glycoconjugates.