Diastereoselective synthesis of D-threo-sphinganine, L-erythro-sphinganine and (−)-spisulosine through asymmetric α-hydroxylation of a higher homologue of Garner's aldehyde

Abstract

A diastereoselective route to the synthesis of D-threo-sphinganine, L-erythro-sphinganine and (−)-spisulosine from the higher homologue of Garner's aldehyde prepared from l-aspartic acid is reported. While the starting material contains one of the stereocenters in the target molecules, the other is generated by proline-catalyzed asymmetric α-hydroxylation of the aldehyde function. The two diastereomers of sphinganine are prepared from the same starting material and using the same sequence of reactions, but for the proline isomer used as the catalyst. The method described is simple and efficient and can easily be extended for the synthesis of other sphingoid bases.