A Convenient Approach to the Synthesis of Glycosphingolipids via the Acidic Decyclization of Hexo-O-acetyl-D-gentiobial

The mercury sulphate catalysed acidic opening of the dihydropyran ring in hexa-O-acetyl-D-gentiobial 2, resulting in (2E,4S,5R)-4-acetoxy- 5-hydroxy-6-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyloxy)hex-2-enal 3 was employed as the key transformation in the synthesis of O-glycosides, which are precursors of glycosphingolipids.