Synthesis of a Polyhydroxylated Tetrahydro-4H-1,2,3-triazolo[1,5-a]azepin, a Higher Homolog of "Nojiritriazole", and of a RelatedC-Disaccharide

Abstract

The first synthesis of a polyhydroxylated tetrahydro-4H-1,2,3-triazolo[1,5-a]azepin derivative ('homonojiritriazole' 7) and of the related C-disaccharide 11 has been achieved from the 5-azido-5-deoxy-D-glucofuranose derivative 4, by way of an acetylide chain-extension and an internal [1,3]-dipolar cycloaddition. Compound 7 was found to be a very weak inhibitor of E. coli a-galactosidase and of isomaltase (a-glucosidase) from baker's yeast.

Iminosugars Spiro-Linked with Morpholine-Fused 1,2,3-Triazole: Synthesis, Conformational Analysis, Glycosidase Inhibitory Activity, Antifungal Assay, and Docking Studies

“…Recently, we have studied the role of gem -disubstituent effect in intramolecular alkyne-azide 1,3-dipolar cycloaddition (AAC) reaction with O-propargylated azido compounds IXa – d by experimental kinetic data and thermodynamic parameters obtained from computational studies (Figure ). During this study, we noticed that the AAC reaction of 1,2;5,6-di- O -isopropylidene-3- O -propargyl-3-azido- d -glucofuranose IXd in the presence or absence of solvent occurred spontaneously at ambient temperature to afford morpholine-fused 1,2,3,-triazole moiety spirocyclic with d -gluco-furanose 5 in 89% yield. We thought of exploiting the same intermediate 5 , by suitable manipulation of 5,6- and 1,2- O -isopropylidene groups of d -gluco-furanose, for the synthesis of targeted spiro-iminosugars.…”