Substitued acids linoleic acid

Fats can be solid or liquid. This physical property is a direct effect of the fatty acid substituents that are present in them. When fats are in their liquid state they are commonly called oils. Broadly we can generalize that solid fats mainly contain saturated fatty acids, and liquid fats mainly contain unsaturated fatty acids. We should not confuse this generalization with the fact that the naturally occurring fats and oils contain many different types of fatty acids, both saturated and unsaturated. The physical properties of fats are mostly a function of the fatty acids that are present in them. For example, human stored fat contains predominantly oleic acid (a saturated fatty acid) which constitutes about 47 % of the total fatty acid content. It also contains palmitic acid, linoleic acid, stearic acid, myristic acid, and other fatty acids in decreasing amounts respectively. 

A series of substituted diaryselenides were examined in three lipid peroxidation model systems isolated rat liver microsomes treated with Fe(II)/(ADP)/ascorbate and isolated rat hepatocytes treated with two different initiators of oxidation. In rat hepatocytes, all of the tellurides performed more effectively than the selenides. Particularly for the rat liver microsome system, the substituent effects on lipid peroxidation were consistent with what would be expected Electron-donating groups give more active compounds, while electron-withdrawing groups give poorer antioxidants. The same trends were seen for substituted diaryItellurides in inhibition of linoleic acid peroxidation in a two-phase model, where the dimethylamino... 

Studies in the mid 20th century identified the effects, in rats, of essential fatty acid deficiency (Table 5). Biochemically, the disease is characterized by changes in the fatty acid compositions of many ceU membranes whose functions are impaired (see British Nutrition Foundation, 1992 Gurr et al., 2002 for further details). One of the striking features of essential fatty acid deficiency in rats is skin dermatitis and water loss (see Mead, 1984). Epidermal lipids are rich in ceramides. The fatty acyl substituent in these is linoleic acid linked via its carboxylic acid group to the terminal methyl carbon of another fatty acid (34 1 n-9) to generate an extremely long-chain (52 carbons) stmcture. 

Allylic aeetates or carbonates can undergo nucleophilic substitutions via palla-dium(0)-catalysis (11). In this paper, we report on the extension of this reaction to unsaturated fatty aeids by the preparation of allyl carbonates and acetates of oleic, linoleic, and 10-undecenoic acid and their substitution with carbon- and heteroatom-nucleophiles by palladium(0)-catalysis. In this way, different substituents can be in-trodueed into the alkyl chain of fatty acids. This leads to fatty acid derivatives in which the properties of biologically active compounds may possibly be combined with the amphiphilic property of the fatty acid. 

CID-MS/MS of lithiated adducts of GPC and GPE lipids exhibit losses of fatty acid substituents [27, 28]. The relative abundances of these ions can reveal the identity and position of the fatty acid substituents. Precursor-ion and neutral-loss scans can provide the identity of the polar head group and the fatty acid substituents. For example, using these scans, GPC species that contain stearate, arachidonate, linoleate, and palmitate have been identified from rat liver extracts [27]. 

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