Chemical synthesis of cyclic galactooligofuranosides isolated from enzymatic degradation products of cell wall arabinogalactan of Mycobacterium tuberculosis

(Chemical Equation Presented) Synthesis of cyclic tetra-, hexa- and octasaccharides containing alternating (1→5)-β- and (1→6)-β-galactofuranosyl linkages has been achieved by intramolecular cycloglycosylation of corresponding linear sugars and by cyclooligomerization of 1,6-linked and 1,5-linked disaccharides. In particular, cyclooligomerization of the (1→6)-β-galactofuranosyl disaccharide provides an efficient way to secure all three cyclic sugars in one operation.