An easy route to seven-membered iminocyclitols from aldohexopyranosyl enamines

γ-Aminoalcohol rearrangement applied to pentahydroxylated azepanes provides pyrrolidines epimeric to homoDMDP

A series of pentahydroxylated pyrrolidines, displaying five contiguous stereogenic centres and epimeric to α-glucosidase inhibitor homoDMDP, have been synthesized. The key step involves a γ-aminoalcohol rearrangement applied to polyhydroxylated azepanes. These five-membered iminosugars demonstrate micromolar inhibition of glycosidases.

N- and C-alkylation of seven-membered iminosugars generates potent glucocerebrosidase inhibitors and F508del-CFTR correctors

The synthesis and biological evaluation of a library of novel seven-membered iminosugars is reported.

Towards a stable noeuromycin analog with a D-manno configuration: synthesis and glycosidase inhibition of D-manno-like tri- and tetrahydroxylated azepanes

Noeuromycin is a highly potent albeit unstable glycosidase inhibitor due to its hemiaminal function. While stable D-gluco-like analogs have been reported, no data are available for D-manno-like structures. A series of tri- and tetrahydroxylated seven-membered iminosugars displaying either a D-manno-or a L-gulo-like configuration, were synthesized from methyl α-D-mannopyranoside using a reductive amination-mediated ring expansion as the key step. Screening towards a range of commercial glycosidases demonstrated their potency as competitive glycosidase inhibitors while cellular assay showed selective albeit weak glycoprotein processing mannosidase inactivation.

Tandem Staudinger-azaWittig mediated ring expansion: rapid access to new isofagomine-tetrahydroxyazepane hybrids

New seven-membered iminosugars with potent and selective inhibition towards glycosidases have been prepared as 1-N-iminosugar homologues via a tandem Staudinger-azaWittig mediated ring expansion.

Polyhydroxylated homoazepanes and 1-deoxy-homonojirimycin analogues: Synthesis and glycosidase inhibition study

The Johnson-Claisen rearrangement of D-gluco and L-ido-derived allylic orthoesters afforded gamma,delta-unsaturated ester that on ester reduction, epoxidation, regioselective oxirane opening by sodium azide and hydrogenation led to sugar amino alcohols--immediate precursors for 1-deoxy-homonojirimycin 3a,b, and polyhydroxylated homoazepanes 4a,b. Our synthetic approach and glycosidase inhibitory activity is reported.

Versatile approach for the synthesis of novel seven-membered iminocyclitols via ring-closing metathesis dihydroxylation reaction

Seven-membered iminocyclitols with diverse diastereomers were prepared starting with d- and l-serines and employing ring-closing olefin metathesis and dihydroxylation reaction sequence. The iminocyclitols were assayed for glycosidase inhibition and compound 20 was found to be a competitive inhibitor for beta-glucosidase with Ki 26.3 microM.

The first synthesis of substituted azepanes mimicking monosaccharides: a new class of potent glycosidase inhibitors

The synthesis of the first examples of seven-membered ring iminoalditols, molecules displaying an extra hydroxymethyl substituent on their seven-membered ring compared to the previously reported polyhydroxylated azepanes, has been achieved from d-arabinose in 10 steps using RCM of a protected N-allyl-aminohexenitol as a key step. While the (2R,3R,4R)-2-hydroxymethyl-3,4-dihydroxy-azepane 10, a seven-membered ring analogue of fagomine, is a weak inhibitor of glycosidases, the (2R,3R,4R,5S,6S)-2-hydroxymethyl-3,4,5,6-tetrahydroxy-azepane 9 selectively inhibits green coffee bean alpha-galactosidase in the low micromolar range (Ki = 2.2 muM) despite a D-gluco relative configuration.