Stereoselective formation of a glycosidic bond remains the main challenge associated with the chemical synthesis of complex glycostructures. The influence of substituents at remote positions of the pyranose ring on the stereoselectivity of glycosylation is increasingly recognized. The project′s aim is to determine how deoxofluorination at C-3 and C-4 of 2-azido-2-deoxy-d-gluco/galactopyranosyl donors affects the glycosylation stereoselectivity. The findings will be the starting point for development of protocols for selective 1,2-cis glycosylation with fluorinated glycosyl donors.