Thiazolylketol Acetates as Glycosyl Donors: Stereoselective Synthesis of a C-Ketoside

We have already proven that thiazolylketol acetates, synthetised by addition of 2-lithiothiazole to sugar lactones followed by acetylation, are efficient glycosyl donors in the presence of O-, N-, and P-nucleophiles. We describe here their first use in the C-glycosidation using trimetylsilyl cyanide as the acceptor in order to prepare, after thiazole-to-formyl unmasking and reduction, the corresponding C-ketosides.