The double reductive amination approach to the synthesis of polyhydroxypiperidines

As a consequence of their inhibitory activity towards a number of carbohydrate-processing enzymes, polyhydroxypiperidines constitute lead compounds for the development of new therapeutic agents in a wide range of diseases. The double reductive amination (DRA) reaction on dicarbonyl compounds represents a straightforward tool to efficiently access the piperidine skeleton. The use, in most cases, of sugar-derived dicarbonyl substrates ensure the absolute configurations desired of the hydroxyl groups, while the variety of amines available as the nitrogen atom source guarantee the versatility of this method. This review collects the representative examples of DRA applied to the synthesis of polyhydroxipiperidines reported to date, together with a concise remark on their biological activity.