Chiral Epoxides for Leukotriene Syntheses : A D-Xylose Approach

Abstract

Characterization of SRS-A, an important mediator of asthma and other hypersensitivity processes, was not achieved until 1979¹. It has been proposed that leukotriene A₄ (LTA₄) is the short-lived key biochemical intermediate which can be either converted to LTB₄ by enzymatic hydration or to LTC₄, a precursor to LTD₄ and LTE₄, by glutathine transfer₂. Therefore, in order to mimic the biosynthetic pathway, LTA₄ has been the prime synthetic target³. A survey of the various methods described in the literature clearly shows the pivotal status of the key-synthons, methyl 7-hydroxy-5, 6-epoxyheptanoates (e.g. 4 and 6).