Naturally occurring epoxy acids. IV. The absolute optical configuration of vernolic acid.

Vernolic acid [(+)-cis-12,13-epoxyleic acid] was transformed by stereospecific reactions to a mixture ofthreo-9,10,12-andthreo-9,10,13-trihydroxyoctadecanols. The four components of this mixture were separately isolated by chromatography on thin layers impregnated with glycol-complexing agents. The 9,10,12-trihydroxyoctadecanols so obtained were identical to the corresponding derivatives of D-(+)-ricinoleic acid, thereby proving the absolute optical configuration of the epoxy group of vernolic acid to be D. As a corollary to this the absolute configurations of some other oxygenated fatty acids have been deduced.