A stereoselective synthesis of pyruvic 4,6-acetals of D-hexopyranose residues

Article abstract of DOI:10.1016/0008-6215(90)84195-Z

A stereoselective synthesis of pyruvic 4,6-acetals in their naturally occuring configurations on α-D-glucopyranose, α-D-mannopyranose, and β-D-galactopyranose residues is based on the preferential formation of 4,6-<1-(3,4-dimethoxyphenyl)ethylidene> acetals bearing equatorial methyl groups. 2,3-Di-O-acyl derivatives of these acetals are oxidized with ruthenium tetraoxide to yield the corresponding 4,6-(1-carboxyethylidene) acetals.Synthesis of allyl 4,6-O-<(S)-1-methoxycarbonylethylidene>-3-O-methyl-β-D-glucopyranoside has been achieved with protection of the allyl glycoside by epoxidation and subsequent regenerative deoxygenation with 3-methylbenzothiazole-2-selone.The allyl glycoside has been subjected in sequence to saponification, ozonolysis, and reductive amination in the presence of bovine serum albumin to furnish a neoantigen.