O-glycosyl trichloroacetimidates bearing Fmoc as temporary hydroxy protecting group: A new access to solid-phase oligosaccharide synthesis

[GRAPHICS] Different O-glycosyl trichloroacetimidates bearing base sensitive Fmoc prot ected hydroxy groups were efficiently prepared with CCl3CN using a catalyti c amount of sodium hydride. The resulting glycosyl donors were engaged in g lycosylation reactions both in solution and on solid support with a new est er-type linker with good results. In both approaches, Fmoc groups were afte rward quantitatively cleaved using mild basic conditions.