Substituted Fatty Acids

Hydroxy Fatty Acids. Ricinoleic acid is the best known of the straight-chain hydroxy fatty acids. Its structure is 12-OH, 18 1 (9). It is an optically active acid with a D(-i-)-configuration  

Furan Fatty Acids. These occur in fish liver oil in a range of 1-6% and up to 25% in some freshwater fish. Furan fatty acids are also part of the minor constituents of some plant oils and butter (Table 3.10). They are also present in fruits (lemon, strawberry), vegetables (cabbage, potato) and mushrooms (champignons). 

Ricinoleic acid is the main acid of castor bean oil, comprising up to 90% of the total acids. Hence, it can serve as an indicator for the presence of this oil in edible oil blends. 

D-2-Hydroxy saturated 16 0 to 25 0 fatty acids with both even and odd numbers of carbons in their chains occur in lipids in green leaves of a great number of vegetables. y- or (9-Lactones are obtained from 4- and 5-hydroxy carboxylic acids (Cg to C16) by the elimination of water. 5-Lactones have been found in milk fat and fruits. They are very active aroma components (cf. S.3.2.3). 

Oxo Fatty Acids. Natural 0x0 (or keto) acids are less common than hydroxy acids. About 1% of milk fat consists of saturated (C10-C24) 0x0 fatty 

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Fats in animal tissue Fat substitutes Fatty acid... 

Approximate, 1990. Table 4 Hsts many of the commercially available substituted fatty acid amides. The /V,/V-dimetby1 amides, ethoxylated amides, and other specialty substituted amides are available ia commercial quantities, but are of lower volume. Table 4. Substituted Fatty Acid Amides ... 

Many substituted, ie, branched, fatty acids, particularly methacryUc, 2-ethylhexanoic, and ricinoleic acids, are commercially significant. Several substituted fatty acids exist naturally (Table 5). Fatty acids with a methyl group in the penultimate position are called iso acids, and those with a methyl group in the antepenultimate position are called anteiso acids (1) (see Carboxylic acids, branched-CHAIN acids). However, the term iso is often used in a broader sense to mean branched or mixtures of branched-chain industrial acids. 

Oxidation of higher fatty acids was first studied in 1904 by Knoop who fed animals with phenyl-substituted fatty acids and analyzed the products in the urine. He showed that the fatty acid oxidation results in the successive cleavage of two carbon moieties from the carboxyl end. Knoop coined the fatty acid oxidation mechanism as n-oxidation. As has been established by Kennedy and Lehninger in 1948-1949, oxidation of fatty acids occurs in the mitochondria only. Lynen and coworkers... 

Interest has been shown in using derivatives of ascorbic acid as antioxidants. One such compound is ascorbyl palmitate. In the structure of ascorbyl palmitate, the 2- and 3-positions are occupied by hydroxyl groups the 6-position contains the substituted fatty acid. Other derivatives, synthesized by Seib and associates were ascorbate-2 phosphate and ascorbate 2-triphosphate (27). Both of these compounds were reported to inhibit lipid oxidation in ground meat as measured by chemical means (2). Ascorbate-2-phosphate was also found to inhibit MFD in beef as measured by sensory means (2). The ascorbate-2-triphosphate was not tested as an inhibitor of MFD in this study, but... 

A number of glycidates are important intermediates in the synthesis of fragrance materials. A few glycidates are fragrance materials in themselves. They are prepared either by epoxidation of the corresponding acrylates or by condensation of aldehydes or ketones with a-chloro substituted fatty acid esters (Darzens reaction). 

The submitter has, by either cuprous chloride-catalyzed or uncatalyzed reactions, prepared a variety of 3-methyl-substituted fatty acids from the adducts of sec-butyl crotonate and other... 

Grignard reagents.4 The uncatalyzed reaction has also been used with set-butyl tiglate to obtain 2,3-dimethyl-substituted fatty acids.7... 

Peng W-J (2008) Extraction process for formyl-substituted fatty acid triglyceride ester separation and catalyst recovery. WO 2008/156993... 

Monofluorinated fatty acids function as fatty acyl substrates for desaturases and can be synthesized in enantiomericafly enriched form via diethylaminosulfur trifluoride (D.A.S.T.) treatment of the suitable chiral alcohols. An example of the use of fluorine-substituted fatty acids as mechanistic probes was demonstrated by the use of chiral 9-fluorostearoyl substrates to induce latent stereoselective 10-hydroxylation by the castor stearoyl ACP desaturase (16). In addition, the advantages... 

One example has been given by Rakshit et al. ) who used [3.4.17] to obtain the Helmholtz energy for monolayers of CjjCOOH. CigCOOH, Cj COOH and C gCOOH, substituted fatty acids and unsaturated acids. The integration was car ried out from (almost) infinite area to r =. the equilibrium spreading pressure. 

In addition to carboxylic acid salts, other effective lubricity additives that the chemist will work with are esters of hydroxyfatty acids, non-ionic surface agents, dibasic acids, and additives from substituted fatty acids. Although this is not a complete list, its contents are the most effective from a cost perspective and are typically used in the industry. The oleate of ricinoleic acid dimer is an example of a hydroxyfatty acid prepared from ricinoleic acid oligomer with acid chloride in the presence of pyridine, as shown in Figure 2.4. 

Fig. 1. The Relation Between the Logarithm of the Acid Dissociation Constant, pKi, in Series of Substituted Fatty Acids, and the Reciprocal of the Number of Carbon Atoms, d, between the Substituent and the Carboxyl Group.

Chlorine compounds are well established in the lexicon of extreme-pressure additives. A wide range of chemical structures has been investigated by bench testing alkyl chlorides, aryl chlorides, chloro-olefins, chlorine-substituted fatty acids, acid chlorides, chlorine-substituted heterocycles, etc. However, investigations of the fundamental modes by which chlorinated additive substances function are scanty. Mostly, therefore, we must resort to conjectures from limited and highly specialized studies such as the work of Buckley [13] described in Section 11.1. The technologically important types of chlorinated additives are alkyl and aryl chlorides of fairly simple structure, and conjectures from their basic chemistry can be reasonable and useful. 

Fig. 6. Structures of common cutin and suberin monomers, and ranges of typical composition values. Non-substituted fatty acids are not represented. There are overlaps in some classes of monomers (e.g. some monomers are epoxy hydroxy-fatty acids, of epoxy dicarboxylic acids).

Ethomids A series of non-ionic surface active agents. The Ethomids are N-substituted fatty acid amides, the substituents being polyoxyethylene groups. In the Etho-mid C series the fatty acids are from coconut oil, in the Ethomid RT series from hydrogenated tallow in the Etho-mid RO series from red oil. 

If the compounds to be halogenated themselves contain COOH groups, their dry silver salts (0.05 mole) can be treated in dry CC14 with iodine or bromine (0.1 mole). Examples are benzoic380 and aryl-substituted fatty acids.381... 

Asiedu, D.K., Demoz, A., Skorve, J., Grav, H.J. Berge, R.K. (1995) Biochem. Pharmacol., 49, 1013-1022. Acute modulation of rat hepatic lipid metabolism by sulphur-substituted fatty acid analogues. 

Sulfur-substituted fatty acids, especially the 3-thia fatty acids (TTA, CH3-(CH2>i3-S-CH2-COOH), that profoundly affect P-oxidation, have facilitated studies on the concerted regulation of fatty acid oxidation and TG-biosynthesis. We have demonstrated that stimulation of p-oxidation (Table 2) may affect both TG-formation (Table 1) and plasma lipoprotein homeostasis (Table 1) under both normolipidemic and hyperlipidemic conditions. 

The incorporation of [ H]-water into synthesized diacylglycerols was reduced even more than the incorporation into the other two lipid classes. As the sulfur-substituted fatty acids had only small effects on incorporation of pH]-water into cell monoacylgjyc-erols (data not shown), these data suggest that 3-thia fatty acids decreased TG-synfliesis by affecting the step before formation of diacylglycerols. The reduced incorporation into diacylglycerols, thus, may indicate that activity of the enzyme phosphatidate phospho-hydrolase could be affected. 

Leaf, A. Weber, P.C. 1988. AC Engl. J. Med 318 549-557. Cardiovascular effects of n-3 fatty acids. Skorve, J. Beige, R.K. 1993. Biochim. Biophys. Acta 1167 175-181. The hypocholesteremic effect of sulfur-substituted fatty acid analogues in rats fed a high carbohydrate diet. 

Skorve, J, Asiedu, D., Rustan, A.C., Drevon, C.A., Al-Shurbaji, A., Berge, R.K. 1990. J. Lipid Res. 31 1627-1635. Regulation of fatty acid oxidation and triglyceride and phospholipid metabolism by hypolipidemic sulfiir-substituted fatty acid analogues. 

Skorve, J, Rustan, A.C. Berge, R.K. 1995. Lipids 30 987-994. Effects of non-beta-oxidizable suUur-substituted fatty acid analogues on synthesis and secretion of triacylglycerol and cholesterol in cultured rat hepatocytes. 

Demoz, A., Svardal, A. Berge, R.K. (1993). BiocherrL Pharmacol. 45 257-259. Relationship between peroxisome-proliferating sulfur-substituted fatty acid analogs, hepatic lipid peroxidation and hydrogen peroxide metabolism. 

Abdi-Dezfuli, F., Froyland, L., Thorsen, T., Aakvag, A. Berge, R.K. (1997). Breast Cancer Res. Treat. 45 229-239. Eicosapentaenoic acid and sulphur substituted fatty acid analogues inhibit the proliferation of human breast cancer cells in culture. 

Growth of rat cancer cells was also reduced by TTA. This suggests that cell lines from other species than human are sensitive to this siilfur substituted fatty acid analogue. Moreover, palmitic acid inhibited the proliferation of rat ghoma cells (BT4Cn) and human leukemic cells (HL-60). However, TTA was more potent. On the growth of hiunan breast cells, EPA was more potent than palmitic add. Evidently, cancer cells may be more... 

F, Parmentier, G., Eyssen, H.J. Mannaerts, G.P. O-Oxidation of 3-methyl-substituted fatty acids in... 

Casteels, M., Croes, K., Van Veldhoven, PP. Maimaerts, G.P. (1994) Biochem. Pharmacol 48, 1973-1975. Aminotriazole is a potent inhibitor of a-oxidation of 3-methyl-substituted fatty acids in rat liver. 

Hovik, R., Osmundsen, H., Berge, R., Aarsland, A. Bergseth, S. 1990. Biochem. J. 270 167-173. Effects of thia-substituted fatty acids on mitochondrial and peroxisomal fi-oxidation. 

Kryvi, H., Aarsland, A. Berge, R.K. 1990. J. Struct. Biol. 103 257-265. Morphologic effects of sulphur-substituted fatty acids on rat hepatocytes with spedal reference to proliferation of peroxisomes and mitochondria. 

The availability of TG is a major driving force in the secretion of VLDL by the hver. Evidently, factors influencing the balance between TG biosynthesis and/ or fatty acid oxidation may ultimately influence plasma hpoprotein levels and metabolism. We have demonstrated this mechanism of action with sulfur-substituted fatty acids (3-thia fatty acids). In rats, the TG-lowering effect of the 3-thia fatty acid tetradecylth-ioacetic acid (C14-S-acetic acid), was estabhshed within hours of feeding and this was mainly due to stimulated mitochondrial fatty acid oxidation, thereby reducing... 

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