Glycosylation of 5-Phenyl-1,3,4-oxadiazole-2-thiol with alpha-D-glucopyranosyl chloride under phase transfer conditions

5-Phenyl-1,3,4-oxadiazole-2-thiol is glycosylated easily and in high yields with 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-alpha-D-glucopyranosyl chloride in the presence of catalytic amounts of aliphatic and aromatic crown ethers under phase transfer (solid-organic solvent) conditions. The reaction rate and the ratio of the resulting N- and S-regioisomers depend on the catalyst nature.