摘要:
An expeditious sialylation reaction with phenylthioglycoside 4 as a sialyl donor and MeSOTf as a promoter was developed. These conditions are very useful for synthesizing ganglioside GM 3 (1), its C-8-ceramide analog 2, and 3-deoxy analog 3 of 2 in an efficient manner. The GM 3 analog 2, whose hydrophilicity is increased by shortening the ceramide moiety, exhibits increased growth inhibiton of KB cells. The 3-hydoxy group of ceramide does not influence its activity against KB cells.