FeCl3-catalyzed α-glycosidation of glycosamine pentaacetates

An efficient method for the large-scale preparation of α-N-acetylglycosaminides, such as fluorogenic TN-antigen probes and an α-GalNAc-Ser derivative, has been achieved using FeCl3-catalyzed one-step condensation between commercially available d-glycosamine pentaacetates and fluorogenic acceptors (or serine acceptor) in refluxing 1,2-dichloroethane. Experimental simplicity, high α-stereoselectivity, low cost, satisfactory yield, and the environmentally benign nature are major advantages of our approach.