Eicosanoic acid

Older versions of the lUPAC rules called the unbranched carboxylic acid with 20 carbon atoms eicosanoic acid. Consequently, icosanoids are often referred to as eicosanoids. 

Coulomb blockade effects have been observed in a tunnel diode architectme consisting of an aluminum electrode covered by a six-layer LB film of eicosanoic acid, a layer of 3.8-nm CdSe nanoparticles capped with hexanethiol, and a gold electrode [166]. The LB film serves as a tunneling barrier between aluminum and the conduction band of the CdSe particles. The conductance versus applied voltage showed an onset of current flow near 0.7 V. The curve shows some small peaks as the current first rises that were attributed to surface states. The data could be fit using a tunneling model integrated between the bottom of the conduction band of the particles and the Fermi level of the aluminum electrode. 

There are three groups of eicosanoids that are synthesized from C20 eicosanoic acids derived from the essential fatty acids linoleate and a-linolenate, or directly from dietary arachidonate and eicosapentaenoate (Figure 23-5). Arachidonate, usually derived from the 2 position of phospholipids in the plasma membrane by the action of phospholipase Aj (Figure 24-6)—but also from the diet—is the substrate for the synthesis of the PG2, 1X2 series (prostanoids) by the cyclooxygenase pathway, or the LT4 and LX4 series by the lipoxygenase pathway, with the two pathways competing for the arachidonate substrate (Figure 23-5). 

The leukotrienes are a family of conjugated trienes formed from eicosanoic acids in leukocytes, mastocytoma cells, platelets, and macrophages by the lipoxyge-... 

Figure 21 LC-MS separation (in elution order) of myristic, palmitic, stearic and eicosanoic acids using positive ESI.

Figure 11.1 Py/methylation GC/MS chromatograms of lead white pigmented linseed oil paint after 610 °C Curie point pyrolysis assisted with on line methylation using 2.5% methanolic TMAH (the sample and TMAH solution was applied onto a rotating Curie point wire pyrolysis time 6 s, interface 180°C). 1, heptenoic acid, methyl ester 2, heptanoic acid, methyl ester 3, butenedioic acid, dimethyl ester 4, butanedioic acid, dimethyl ester 5, octenoic acid, methyl ester 6, octanoic acid, methyl ester 7, pentenedioic acid, dimethyl ester 8, pentanedioic acid, dimethyl ester 9, nonanoic acid, methyl ester 10, hexanedioic acid, dimethyl ester 11, decanoic acid, methyl ester 12, heptanedioic acid, dimethyl ester 13, octanedioic acid, dimethyl ester 14, 1,2 benzenedicarboxylic acid, dimethyl ester 15, a methyl octanedioic acid, dimethyl ester 16, nonanedioic acid, dimethyl ester 17, a methoxy octanedioic acid, dimethyl ester 18, a methyl nonanedioic acid, dimethyl ester 19, a,a dimethyl nonenedioic acid, dimethyl ester 20a, a methyl nonenedioic acid, dimethyl ester 20b, a,a dimethyl nonanedioic acid, dimethyl ester 21, decanedioic acid, dimethyl ester 22, a methoxy nonanedioic acid, dimethyl ester 23, a methyl decan edioic acid, dimethyl ester 24, undecanedioic acid, dimethyl ester 25, a methoxy decan edioic acid, dimethyl ester 26, pentadecanoic acid, methyl ester 27, dodecanedioic acid, dimethyl ester 28, hexadecanoic acid, methyl ester 29, heptadecanoic acid, methyl ester 30, octadecanoic acid, methyl ester 31,8 methoxy 9 octadecenoic acid, methyl ester 32, 11 methoxy 9 octadecenoic acid, methyl ester 33, 9 methoxy 10 octadecenoic acid and 10 methoxy 8 octadecenoic acid 34, 9 oxo octadecanoic acid, 10 oxo octadecanoic acid 35, 9 epoxy octadecanoic acid 36, eicosanoic acid, methyl ester 37, 9,10 dimethoxy octadecanoic acid, methyl ester 38, docosanoic acid, methyl ester. Reprinted from J. Anal. Appl. Pyrol., 61, 1 2, van den Berg and Boon, 19, Copyright 2001, with permission from Elsevier...

Tamarindus indicus L. Luo Huang Zi (Tamarind) (stem, fruit) Tannins, beta-amyrin, campesterol, beta-sitosterol, palmitic acid, oleic acid, linoleic acid, eicosanoic acid, arabinose, xylose, galactose, glucose, uronic acid, pectins, mucilage, vitamin B.60-216 Diuretic, purgative, for liver disorders, inappetence, digestion, and hypoglycemic, hypocholesterolemic properties. 

Figure 21-8 The 5-lipoxygenase pathway for biosynthesis of the hydroperoxy- and hydroxy-eicosanoic acids, leukotrienes, and lipoxins.

Pentacosene 1-Hexacosene 1-Heptacosene 1-Octacosene 1-Nonacosene 1-Triacontene Dodecanal Tridecanal Tetradecanal Pentadecanal Hexadecanal Heptadecanal 17- Oxooctadecanoic acid 18- Oxononadecanoic acid 2-Oxopentanedioic acid Nonadecanoic acid methylester Eicosanoic acid methylester Heneicosanoic acid methylester... 

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