Double Reductive Amination and Selective Strecker Reaction of a D-Lyxaric Aldehyde: Synthesis of Diversely Functionalized 3,4,5-Trihydroxypiperidines

A D-mannose-derived aldehyde with the D-lyxo configuration is a versatile key intermediate to functionally and stereochemically diversified piperidines. It allowed the synthesis of natural 3,4,5-trihydroxypiperidines and new analogs through a double reductive amination strategy and the synthesis of novel 2-cyanotrihydroxypiperidines through a highly regio- and diastereoselective Strecker reaction.