Phosphono-sphingomyelins. I: Synthesis of ceramide (trimethyl) aminoethyl phosphonate

The synthesis of the phosphono-analogue of sphingomyelin is described. The N-acyl-D-erythro-sphingosyl-1-(N,N,N-trimethyl-2-aminoethyl) phosphonate was obtained by phosphonylation of N-acyl-3-O-benzoyl-D-erythro-sphingosine with (2-bromoethyl)phosphonic acid chloride and triethylamine, subsequent quaternisation with anhydrous trimethylamine and benzene at 55–60°C for four days, and finally, consecutive removal of the protective group by mild alkaline hydrolysis. Comparison of the CD spectra of both, natural sphingomyelin and its phosphono-analogue, confirmed that their structures and configurations were identical.