Long-Range Stereodirecting Participation across a Glycosidic Linkage in Glycosylation Reactions.

The formation of an unprecedented 12-membered macrocyclic ketal through the long-range participation of a levulinoyl group across a glycosidic linkage was observed in glycosylation reactions. This finding indicated that stereodirecting participation is not limited to groups within the glycan ring being activated, thus broadening the scope of remote group participation in glycosylation.