Olefin self-metathesis as a new entry into xenotransplantation antagonists bearing the Galili antigen

A hexameric disaccharide cluster bearing the terminal Gal related xenotransplantation antigen was constructed using a sequence of ruthenium carbenoid catalyzed olefin self-metathesis of monoallylated tribenzyl pentaerythritol followed, after interconversion of benzyl ethers into para-iodobenzyl ethers, by a single step Sonogashira cross-coupling of six prop-2-ynyl glycosides onto a hexameric aryl iodide scaffold.