Synthesis of 11,12‐leukotriene A4, 11S,12S‐oxido‐5Z,7E,9E,14Z‐eicosatetraenoic acid, a novel leukotriene of the 12‐lipoxy genase pathway

Abstract
A simple and efficient method for preparing 11,12‐leukotriene A4 has been established by the stereospecific biomimetic route from arachidonic acid. 12S‐Hydroperoxy‐5Z,8Z,10E,14Z‐eicosatetraenoic acid was synthesized using a partially purified 12‐lipoxygenase of porcine leukocytes. The methyl ester of the compound was then chemically converted to two labile epoxides with a conjugated triene structure. These compounds were identified by proton NMR and mass spectrometry to be 11S,12S‐oxido‐5Z,7E,9E,14Z‐eicosatetraenoic acid (11,12‐leukotriene A4) and its geometric isomer.