Syntheses of novel tetrazolo azepanes by intramolecular 1,3-dipolar cycloaddition are described. Cyclization mechanistic topology study showed a pseudo concerted mechanism.

Sugar epoxide derivatives play a crucial role in the syntheses of diverse compounds which can act as glycosidase inhibitors. This review collects a number of syntheses that target different sugar derivatives belonging to the principal families of glycosidase inhibitors, of which epoxide derivatives are key precursors.

Reaction of 3-O-benzyl-1,2-O-isopropyl-idene-α-xylo-pentodialdo-1,4-furan-ose with N,N-diethyl-2-(dimethyl-sulfuranil-idene)acetamide gave stereoselectively an ep-oxy-amide, which was regioselectively opened by NaN(3) in dimethyl formamide to give the title compound, C(21)H(30)N(4)O(6). X-ray crystallography confirmed the relative stereochemistry of the title compound and the absolute configuration was determined by the use of d-glucose as the starting material. There are two mol-ecules in the asymmetric unit (Z' = 2). The crystal structure consists of two types of chains of O-H⋯O hydrogen-bonded mol-ecules running parallel to the b axis, with each mol-ecule acting as a donor and acceptor of one hydrogen bond.