Synthesis of 6-S-(5-Acetamido-3,5-Dideoxy-D-Glycero-α-D-Galacto-2-Nonulopyranosylonic Acid)-6-Thio-Hexopyranosides

Abstract
The reaction of the sodium salt of methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-thio-D-glycero-.alpha.-D-galacto-2-nonulopyranosonate with a variety of 6-bromo-6-deoxy-D-hexopyranosides, such as methyl 2,3,4-tri-O-acetyl-6-bromo-6-deoxy-.alpha.-D-glucopyranoside, -galactopyranoside, allyl 2,3,4-tri-O-acetyl-6-bromo-6-deoxy-.beta.-D-glucopyranoside, and allyl 2-acetamido-3,4-di-O-acetyl-6-bromo-2,6-dideoxy-.beta.-D-glucopyranoside, gave the corresponding (2 .fwdarw. 6)-linked disaccharides, .alpha.-glycosides of 2-thio-N-acetylneuraminic acid derivative in good yields. These disaccharides were converted, via O-deacetylation, followed by hydrolytic removal of the ester group, into the title compounds.