A SYNTHESIS OF D-ERYTHRO-SPHINGOSINE AND L-THREO-SPHINGOSINE AND SPHINGANINE DIASTEREOMERS VIA THE BIOMIMETIC PRECURSOR 3-KETOSPHINGANINE

The four stereoisomers of sphingosine and sphinganine can be produced in protected form by a short, convergent, biomimetic synthesis from se rine. Yields are good (26-38% overall from commercially available seri ne derivatives), and the stereoselectivities are excellent (>92% de, > 95% eel. Several sphingosine L-threo-sphingosine analogues with modifi ed, functionalized tails were prepared to demonstrate the versatility of the method.