Synthesis of a new conformationally constrained glycoamino acid building block

The synthesis of a suitably protected β-d-glucopyranosyl-(S)-α-methylserine derivative—a new conformationally constrained glycosylated quaternary amino acid analogue of β-d-glucopyranosyl-l-serine—is described. This compound can be used as an attractive building block for the synthesis of new, constrained glycopeptides.