Unusual fatty acids

Introduction Primary Fatty Acids Fatty Acids of Plant Vegetative Parts Biosynthesis Fatty Acid Biosynthesis The Two-Pathway Model of Lipid Biosynthesis The Second 3-Ketoacyl ACP Synthase Isozyme Biosynthesis of Unsaturated Fatty Acids The Prokaryotic Pathway The Eukaryotic Pathway Biosynthesis of Triacylglycerides Degradation of Fatty Acids Unusual Fatty Acids in Plants Fatty Acids from Unusual Starter Units Fatty Acids with Unusual Patterns of Unsaturation Hydroxy Fatty Acids Epoxy Fatty Acids... 

More frequentiy, alkyd resias are described by a combiaed classification ia terms of thek oil length, the type of fatty acids, and any unusual kigredients. Such descriptions as an isophthaUc, very long tall oil alkyd a medium oil dehydrated castor-PE ( pentaerythritol, not polyethylene) alkyd or a short oil lauric-ben2oic alkyd, immediately project the general properties of the reski. 

FIGURE 8.2 Structures of two unusual fatty acids lactobacillic acid, a fatty acid coutaiuiug a cyclopropane ring, and tuberculostearic acid, a brauched-chaiu fatty acid. 

By the radical pathway l, -diesters, -diketones, -dienes or -dihalides, chiral intermediates for synthesis, pheromones and unusual hydrocarbons or fatty acids are accessible in one to few steps. The addition of the intermediate radicals to double bonds affords additive dimers, whereby four units can be coupled in one step. By way of intramolecular addition unsaturated carboxyhc acids can be converted into five raembered hetero- or carbocyclic compounds. These radical reactions are attractive for synthesis because they can tolerate polar functional groups without protection. 

The important but unusual fatty acid ricinoleic acid, or 12-hydroxyoleic acid, is a major component of castor oil (>87%) and is also found in useful quantities in ergot. The metal salts of the acid find use in dry-cleaning soaps but the majority is converted to aminoundecanoic acid (Scheme 6.6) which is used to make nylon 11. Nylon 11 has very good chemical and shock-resistance properties, which have led to it being used in the automotive industry. Ricinoleic triglyceride is initially transesterified to the methyl ester. This is heated to 300 °C at which temperature it is... 

Kennedy, M.W., Scott, J.C., Lo, S.J., Beauchamp, J. and McManus, D.P. (2000) The Sj-FABPc fatty acid binding protein of the human blood fluke Schistosoma japonicum structural and functional characterisation and unusual solvent exposure of a portal-proximal tryptophan. BiochemicalJournal 349, 377-384. 

It has been suggested [6] that these unusual sterols, especially in those cases where these unusual sterols comprise the entire sterol content of the organisms, likely replace conventional sterols as cell-membrane components. Evidence for this comes from subcellular fractionation and subsequent analysis of two marine sponges [10]. The sterol composition of the membrane isolates was found to be identical to that of the intact sponge. Most common variation of the marine sterol is in the side-chain, situated deep in the lipophylic environment of the phospholipid bilayer. This suggests that unusual fatty acids might accompany the sterols, and indeed this is often the case [8]. 

There exists an unusual uniformity in the fatty acid composition of the inositol lipids. All three of the major phosphoinositides are enriched in the 1-stearoyl, 2-arachidonoyl ( ST/AR ) sn-glycerol species (=80% in brain). The polyphosphoinositides (PI4P and PI(4,5)P2) are present in much lower amounts than PI. PI(4,5)P2 has been shown to be predominantly, although not... 

In lipid A of Moraxella catarrhalis an unusual lipid A was identified possessing an asymmetrical (3 + 4) acylation pattern with four 12 0(3-OH) residues as primary fatty acids, three of which are acylated to form acyloxya-cyl residues [12 0(3-0(10 0)] at positions 2 and 3 and [12 0(3-0(12 0)] at position 2 (193b). 

Theoretical calculation potentialities have been examined in few chapters, giving new instruments to predict fullerene solubility in different solvents, such as fatty acid esters. Visualization approaches necessary to study unusual compounds such as CNT are herein presented. Despite the structural novelty of CNT, its resemblance to cellular structures is highlighted, launching or confirming the hypothesis of using CNTs as communication devices between cells. 

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