Chemoenzymatic synthesis of high-mannose type HIV-1 gp120 glycopeptides

A chemoenzymatic approach to the synthesis of glycoforms of HIV-1 gp120 glycopeptides is described. Thus, the high-mannose type glycopeptides [gp120 (336–342)] containing Man9, Man6 and Man5 moieties, respectively, were synthesized in satisfactory yields via transglycosylation to the acetylglucosaminyl peptide, using the recombinant Arthrobacter Endo-β-N-acetyl-glucosaminidase (Endo-A) as the key enzyme.