SYNTHESIS OF NEUTRAL PLASMALOGENS

The cis- and trans-isomers of the di-O-stearoyl and di-O-palmitoyl esters of 1-O-hexadec-1′-enyl-L-glycerol and 1-O-tetradec-1′-enyl-L- glycerol and the cis- and trans-isomers of 1-O-octadec-1′-enyl-2,3-di-O- stearoyl-L-glycerol were obtained by separation of the cis-trans mixtures by t.l.c. on silica gel-silver nitrate. The cis-isomers of the di-O-palmitoyl derivatives were also obtained free from the trans-isomers by fractional crystallisation. 1-O-Heptadec-2′-enyl-2,3-O-isopropylideneglycerol is rapidly degraded by potassium t-butoxide in dimethyl sulphoxide at 50° but 1-O-hexadec-1′-enyl-2,3-di-O-methylglycerol is comparatively stable under these conditions.