Selective deuterium labeling of the sphingoid backbone: facile syntheses of 3,4,5-trideuterio-d-erythro-sphingosine and 3-deuterio-d-erythro-sphingomyelin.

Deuteration at C-4 and C-5 of sphingosine was achieved via a hydrogen-deuterium exchange reaction of a β-ketophosphonate intermediate catalyzed by ND₄Cl in D₂O/tetrahydrofuran. To install deuterium at C-3 of sphingosine and sphingomyelin, sodium borodeuteride reduction/cerium(III) chloride reduction of an α,β-enone in perdeuteromethanol was used.