General methods for the synthesis of glycopyranosyluronic acid azides Original Research Article

Per-O-acetylated d-glycopyranoses derived from both mono- and disaccharides were first converted to glycosyl iodides and subsequently reacted with an azide source to achieve the stereoselective synthesis of β-d-glycosyl azides after deacetylation. Low-temperature (4 °C) TEMPO oxidation of the monosaccharides provided the corresponding uronic acids, which were purified as the free acids. Oxidation of the lactosyl- and cellobiosyl azides resulted in diacid formation. However, 4′,6′-O-benzylidene protection enabled selective oxidation of the C-6 hydroxyl. 2-Acetamido-2-deoxy-d-glycopyranosyl azides were also prepared and converted to uronic acids completing the library synthesis.