Concise synthesis of an arabinofuranose hexasaccharide present in the cell wall of Mycobacterium tuberculosis

Mycobacterium cell wall consists of three major polysaccharide portions and arabinofuranose (Araf) is present in two of the major portions, arabinogalactan (AG) and lipoarabinomannan (LAM). A peculiar Araf hexasaccharide possessing two β-linked Araf units are present in both AG and LAM polysaccharides. Herein, we report an efficient and concise synthesis of this Araf hexasaccharide using single starting 3,5-TIPDS protected Araf thioglycoside precursor. Double β-glycosylation was achieved using strained cyclic 2-p-methoxybenzyl-3,5-TIPDS Araf thioglycoside donor.