Synthesis of Polyhydroxylated Azetidine Iminosugars and 3‐Hydroxy‐N‐methylazetidine‐2‐carboxylic Acid from D‐Glucose.

The azetidine iminosugars, (2S,3R)-2-((R)-1,2-dihydroxyethyl)azetidin-3-ol 3, (2R,3R)-2-(hydroxymethyl)azetidin-3-ol 4, and (2S,3R)-3-hydroxy-N-methylazetidine-2-carboxylic acid 5 were synthesized from d-glucose derived 3-N-benzyloxycarbonyl-3-deoxy-1,2-O-isopropylidene-α-d-xylofuranose 8 using intramolecular Mitsunobu reaction as a key step. The glycosidase inhibitory activity of compounds 3–5 was screened against various enzymes. Amongst all synthesized compounds, the N-methylated compound 5 exhibited significant inhibitory activity against amyloglucosidase from Aspergillus niger in micro molar range.