Synthesis of the Reducing-end Hexasaccharide Fragment of Marine Lipopolysaccharide Axinelloside A.

Chemical synthesis of an orthogonally protected hexasaccharide relevant to the reducing-end half of axinelloside A, a highly sulfated marine lipopolysaccharide, is disclosed. The synthesis features preparation of the scyllo-inositol unit via a Ferrier-type-II rearrangement, construction of the 1,2-cis-glycosidic bonds via remote participation, and concise [2+2+2] assembly via Au(I)-catalyzed glycosylation.