Synthesis of 10( S )-Hydroxyeicosatetraenoic Acid:  A Novel Cytochrome P-450 Metabolite of Arachidonic Acid

10( S) -(−)-hydroxyeicosa-5( Z ),8( Z ),11( Z ),14( Z )-tetraenoic acid methyl ester ( 2 ) was synthesized in eight steps starting from enantiomerically pure ( R )-glyceraldehyde acetonide. The 10( R )-(+)-enantiomer was prepared using an identical method except that the starting material was ( S )-glyceraldehyde acetonide. By use of these authentic standards, it was possible to confirm that arachidonic acid was converted to a mixture of 10( S )-(−)-hydroxyeicosa-5( Z ),8( Z ),11( Z ),14( Z )-tetraenoic acid ( 1 ) and the 10( R )-(+)-enantiomer by phenobarbital-induced rat liver microsomes.