A series of 5′-O-glycosyl-uridine and thymidine derivatives have been prepared as potential mimics of sugar nucelotides and nucleotide-diphosphates. These compounds proved not to be inhibitors of bovine β-1,4-galactosyltransferase although some showed moderate inhibition of Salmonella dTDP-α-D-glucose 4,6-dehydratase (RmlB).