Direct N-Glycosylation of Amides/Amines with Glycal Donors

Direct N-glycosylation between glycals and amides/amines was achieved with exclusive stereoselectivity in moderate to high yields. Various amides, amines, and 3,4-O-carbonate-glycals were tolerated, and unique β-N-glycosides were obtained. The strategy was based on palladium-catalyzed decarboxylative allylation, and the high 1,4-cis-selectivity was proposed because of the hydrogen bonding effect. Notably, all the synthesized products were subjected to preliminary bioactivity studies, revealing that three compounds were cytotoxic to tumor cells and nontoxic to normal human cells.