Enantiopure suitably N,O-protected aminotriol has been prepared from D
-isoascorbic acid. The utility of this homochiral building block in th
e synthesis of (2R,3R)-D-threo-C-18-sphingosine is described via a Wit
tig reaction on a N,O-protected beta-amino-alpha-hydroxyaldehyde. (C)
1996 Elsevier Science Ltd