Synthesis of the Glycosphingolipid β-Galactosyl Ceramide and Analogues via Olefin Cross Metathesis

The preparation of the glycosphingolipid galactosyl ceramide from an orthogonally protected five-carbon building block is described. The main chain of the lipid is installed via a highly stereoselective olefin cross metathesis reaction. The methodology permits the facile preparation of glycolipids which vary in the length of the main carbon chain.