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Herein we report a one-pot and efficient method for the synthesis of a 1,2-cis fused furanoside bicyclic oxazolidinone derivative of D-glucosamine via pyranose to furanose conversion and concomitant cyclization involving the N-Troc group. The D-glucosamine oxazolidinone derivative was efficiently transformed into oxazolidinones of D-xylosamine, D-allosamine and D-ribosamine.

The MECA-79 antigen is a sulfated mucin type core-1 extended O-glycan which is a potential anti-inflammatory agent. Herein we report a total synthesis of MECA-79 via a convergent [2 + 2] glycosylation route. The synthesis relies on efficient transformation of D-glucosamine into the orthogonally protected Tn antigen derivative and its elaboration into the TF antigen en route to MECA-79.

Trehalose dibenzylidene and substituted dibenzylidene acetals were reductively opened either at O6 or O4 in a regioselective manner by using a DIBAL stock solution prepared in toluene or dichloromethane, respectively, to achieve desymmetrization of the trehalose core. The method was applied to synthesize various biologically important unsymmetrically substituted trehalose glycoconjugates, including a mycobacterial trisaccharide, a 4-epi-trehalosamine analog and a maradolipid.

Synthesis of beta-C-D-galactosyl D- and L-alanines is carried out via a highly stereoselective Grignard reaction of glycosyl iodides, Sharpless dihydroxylation and S(N)2 displacement of the corresponding mesylate or tosylate. Alternatively, attempted triflation of the intermediate alcohols triggers a stereoselective debenzylative cyclization leading to interesting bicyclic trans-fused compounds.