Biologically active ether lipids

Biotransformation of rac ‐1(3)‐ O ‐hexadecylglycerol by photomixotrophic rape ( Brassica napus ) cells in suspension culture leads to 1‐ O ‐hexadecyl‐2‐acyl‐ sn ‐glycero‐3‐phosphocholines and small proportions of other ether lipids, e.g. 1‐ O ‐hexadecyl‐2‐acyl‐ sn ‐glycero‐3‐phosphoethanolamines. Reaction of the hexadecylacyl‐glycerophosphocholines with ethanolamine in the presence of phospholipase D from Streptomyces chromofuscus yields additional hexadecylacylglycerophosphoethanolamines. Partial hydrolysis of the combined hexadecylacylglycerophosphoethanolamines followed by reacylation of the resulting lyso compound with palmitic anhydride gives 1‐ O ‐hexadecyl‐2‐palmitoyl‐ sn ‐glycero‐3‐phospho‐( N ‐palmitoyl) ethanolamine, a nontoxic ether glycerophospholipid with antitumor activity. The corresponding 1‐ O ‐tetradecyl,1‐ O ‐octadecyl, and 1‐ O ‐[( Z )‐9'‐octadecenyl] derivatives are prepared similarly.