Synthesis of glycosylated peptide templates containing 6′-O-phosphorylated mannose disaccharides and their binding to the cation-independent mannose 6-phosphate receptor

The multiple-column peptide synthesis of eleven glycopeptides containing two 6′-O-phosphorylated mannose disaccharides linked either α(l → 2) or α(l → 6) is described. Binding-inhibition studies were performed on the cation-independent mannose 6-phosphate receptor, revealing glycopeptides containing two 6′-O-phosphorylated α(1 → 2)-linked mannose disaccharides to be potent inhibitors of the receptor binding to a phosphomannan core fragment.