N-Butyl-<scp>l</scp>-deoxynojirimycin (<scp>l</scp>-NBDNJ): Synthesis of an Allosteric Enhancer of α-Glucosidase Activity for the Treatment of Pompe Disease

The highly stereocontrolled de novo synthesis of L-NBDNJ (the unnatural enantiomer of the iminosugar drug Miglustat) and a preliminary evaluation of its chaperoning potential are herein reported. L-NBDNJ is able to enhance lysosomal α-glucosidase levels in Pompe disease fibroblasts, either when administered singularly or when co-incubated with the recombinant human α-glucosidase. In addition, differently from its D-enantiomer, L-NBDNJ does not act as a glycosidase inhibitor.