Studies on the Thioglycosides of N-Acetylneuraminic Acid 1: Synthesis of Alkyl α-Glycosides of 2-Thio-N-Acetylneuraminic Acid

Abstract
Methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-2-S-acetyl-3,5-dideoxy-2-thio-D-glycero-.alpha.-D-galacto-2-nonulopyranosonate (2) was prepared via methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-2-chloro-2,3,5-trideoxy-D-glycero-.alpha.-D-galacto-2-nonulopyranosonate (1) and was converted into the sodium salt (3). Condensation of 3 with n-alkyl bromides gave the corresponding methyl (alkyl 5-acetamido-4,7,8,9--tetra-O-acetyl-3,5-dideoxy-2-thio-D-glycero-.alpha.-D-galacto-2-nonulopyranosid) onates, which were converted, via O-deacetylation and hydrolysis of the methyl ester group, into the title compounds.