Oxidative radical decarboxylation of uronic acids: Convenient synthesis of C-Glycosylated isoquinolines

An expedient approach to C-glycosylated isoquinolines was established based on the coupling of vinyl isonitriles with tetrafuranos-4-yl and pentapyranos-5-yl radicals generated from oxidative decarboxylation of uronic acids derived from monosaccharides and complex oligosaccharides. This approach enjoyed a broad substrate scope and good functional group tolerance, and afforded structurally diverse C-glycosylated isoquinolines in the presence or absence of silver salts. Deprotection of the coupling products was conducted to yield C-glycosylated isoquinolines with multiple hydroxyl groups. These novel architectures would offer opportunities for investigation of their bioactivities.