Selective Epoxidation of Arachidonic Acid

This remarkably selective internal epoxidation of peroxyarachidonic acid to form 14,15-oxido-arachidonic acid occurs as shown because of unusually favorable stereoelectronics. The corresponding reaction sequence with eicosa-(E)-8,ll,14-trienoic acid affords the Ai4,i5 epoxide in 94% isolated yield and 95% purity. 

The (Z)-8-eicosen-5-ynoic acid F, another rationally devised irreversible inhibitor of the biosynthesis of leukotrienes and SRS-A s was synthesized as shown below (Ref. 3)  

---

Corey has described routes leading to the selective epoxidation of arachidonic acid. He showed that peroxyarachidonic acid undergoes intramolecular reaction to give cw-14,15-epoxy 20 3 possibly via the cyclic intermediate shown ... 

Corey EJ, Nirva H and Falck JR Selective epoxidation of arachidonic acid and eicosatrienoic acid. J Am Ckm Soa 101 1586-1587, 1979. 

An ingenious selective epoxidation of arachidonic acid (12) has been devised by preparing peroxyarachidonic acid (13), which internally epoxidases the 14,15-double bond, as shown in Scheme 12. The 5,6-epoxide of arachidonic acid is also available by the route shown in Scheme 13. 

Brand-Schieber, E., J.F. Falck, and M. Schwartzman (2000). Selective inhibition of arachidonic acid epoxidation in vivo. J. Physiol. Pharmacol. 51, 655-672. 

Corey and coworkers devised a highly selective internal epoxidation of arachidonic acid (8) to afford epoxy methyl... 

Corey EJ, Niwa H, Falck JR (1979) Selective epoxidation of ecosa-cis-5, 8, 11, 14-tetraenoic (arachidonic) acid and eicosa-cis-8,11,14-trienoicacid. J Am Chem Soc 101 1586-1587... 

Selective epoxidation of the 5,6-double bond is based on the iodolactonization reaction which involves only the 5,6-double bond in arachidonic acid ... 

For the synthesis of hydroperoxides (HPETE compounds), the corresponding alcohols (HETE Compounds) and the selective formation of epoxides, arachidonic acid (89) has been primarily involved (ref.94) as depicted. 

---