Synthesis and characterization of some nitrogen heterocycles from D-galactose derivatives

The tetrazoles 5-(6'-acetamido-6'-deoxy-1',2':3',4'-di-O-isopropylidene-D-g lycero-alpha-D-galactohexopyranos-6'-yl)tetrazole (1) and 5-(6'-acetamido-6 '-deoxy-1',2':3',4'-dihexopyranos-6'-yl)-tetrazole (2) were synthesized by the 1,3-dipolar cycloaddition reaction of the epimeric alpha-acetamidonitri les 5 and 6, respectively, with sodium azide. Reaction of tetrazole 1 with acetic anhydride in the presence of pyridine afforded the N-acetyl-1,3,4-ox adiazole derivative 3 and the N-acetylacetamido-1,3,4-oxadiazole derivative 7. The N-acetylacetamido-1,3,4-oxadiazole derivative (8) was isolated when the tetrazole 2 was allowed to react under the same conditions. The physic al and spectroscopic data of the five new compounds 1, 2, 3, 7 and 8 are pr esented.