Convenient strategy for the synthesis of highly functionalizable hydroxylated unsaturated azepanes

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.

Synthesis of 2-carboxymethyl polyhydroxyazepanes and their evaluation as glycosidase inhibitors

A series of diastereomeric tetrahydroxylated azepanes featuring a carboxymethyl group at the pseudo-anomeric position have been synthesized from a common unsaturated intermediate. Syn- and anti-dihydroxylation reactions were achieved to yield the target compounds after efficient one-step deprotection of carbamate, ester and acetonide groups simultaneously. Screening of these polyhydroxylated azepanes toward a range of commercially available glycosidases was performed and one of the stereoisomers showed potent and selective inhibition toward β-galactosidase (IC50=21 μM).

Solvent Polarity-Controlled Selective Synthesis of Methyl Pyranoside and Furanoside

A selective synthesis of methyl d-glucopyranoside or furanoside has been developed using 2,4,6-trichloro-1,3,5-triazine (TCT)-activated DMSO and d-glucose in methanol. At higher concentrations of DMSO, only pyranoside was formed and at lower concentrations of DMSO, only furanoside was formed. This method was also successfully applied to other sugars. In terms of reaction rates, selectivities, and yields, this method is better than most of the currently used methods.