11(R)-HETE is biosynthesized by 11(R)-LOs of the sea urchin, S. purpuratus, and the fresh water hydra, H. vulgaris. The biological activity of 11(R)-HETE relates to oocyte maturation and tentacle regeneration, respectively, in these two species. 11(R)-HETE is also produced when aspirin-treated recombinant COX-2 is incubated with arachidonic acid. Stereochemical assignment of the (R) enantiomer is based on comparison of chiral HPLC retention times to published results.

(±)11-HETE is one of the six monohydroxy fatty acids produced by the non-enzymatic oxidation of arachidonic acid . The individual R and S isomers of racemic HETEs have been separated and identified using chiral phase HPLC. The racemic HETEs have been quantified as an index of lipid peroxidation using GC/MS.

The lipoxins are trihydroxy fatty acids containing a 7,9,11,13-conjugated tetraene. Lipoxin A4 (LXA4) was first described as a metabolite of 15-HpETE and/or 15-HETE when added in vitro to isolated human leukocytes. The material obtained in this manner consists of at least four distinct isomers: 5(S), 6(S); 5(S), 6(R); and the 11-trans and 11-cis isomers of each of these. 6(S)-LXA4 is one of the original four metabolites first identified by Serhan, Nicolaou, and Samuelsson. It was considered to be an artifact by these authors because it lacked the potency of the 5(S),6(R) isomer with respect to contraction of isolated guinea pig lung parenchymal strips. It has not been possible to isolate natural LXA4 from humans or other mammals in amounts sufficient for determination of absolute stereochemistry. Most authors refer to LXA4 as the 5(S)

11(S)-HETE, an (S) enantiomer of 11(R)-HETE and a type of oxylipin, is non-enzymatically synthesized from arachidonic acid. Compared to its counterpart, 11(S)-HETE levels are found to be elevated in both isolated human plasma and serum, as well as in LPS-stimulated isolated human plasma. Notably, patients with allergic rhinitis exhibit a decrease in 11(S)-HETE levels in their serum following one year of double-mite subcutaneous immunotherapy (DM-SCIT), correlating with an enhanced quality of life, particularly in aspects related to rhinoconjunctivitis.

CAY10397, a selective inhibitor of 15-hydroxy PGDH, significantly suppresses endogenous 11-oxo-ETE production with a corresponding increase in 11(R)-HETE.