Fatty acids carboxylic acid group

A) and glycerol (Fig. 3-8B). Three fatty acids (carboxylic acids with long hydrocarbon tails) combine with one molecule of glycerol to form a triglyceride. More complex lipids are formed by the addition of other groups, the most important of which contain phosphorus (Fig. 3-8C). 

Figure 27.1 A soap micelle solubilizing a grease particle in water. An electrostatic potential map of a fatty acid carboxylate shows how the negative charge is located in the head group.

These results are quite compatible with the preferred conformations of the two-chain carbonyl diacids in aqueous media mentioned above (Porter et al, 1986b, 1988). The meso-compounds preferred collinear conformation, which places the hydrogens at the asymmetric carbons in a nearly eclipsed position relative to each other (Fig. 44), is more stable than that of the ( )-diastereomer by about 1.2kcalmol 1. In this conformation, the two carboxylic acid groups at the ends of the chain can be attached to the water surface side-by-side. The entire molecule can then behave as a good-amphiphile whose structure is similar to a pair of single-chain fatty acid molecules bound side-by-side, each chain mirroring the other about the molecules plane of symmetry. 

From Nocardia strains several closely related compounds (nocobactins, formo-bactin, amamistatins) were isolated that contain three typically Fe " binding sites, two hydroxamate units, and ahydroxyphenyloxazole stmcture (cf. Sect. 3.2 below). The C-terminus is A-hydroxy-cyc/o-Lys bound to a long chain 3-hydroxy fatty acid, whose hydroxy group is esterified by A -acyl-A -hydroxy-Lys, the a-amino group of which is bound to 2-o-hydroxyphenyl-5-methyl-oxazole-4-carboxylic acid (Table 4). For the amamistatins the configuration of the cyclic lysine was determined as L, the open one as d, and that of C-3 of the fatty acid as (S). The involvement in the iron metabolism was not investigated. 

Butyric acid is one of the simplest fatty acids. Fatty acids, which are the building units of fats and oils, are natural compounds of carbon chains with a carboxyl group (-COOH) at one end. Most natural fatty acids have an unbranched carbon chain and contain an even number of carbon atoms because during biosynthesis they are built in two carbon units from acetyl coenzyme A (CoA). Butyric acid is an unsaturated fatty acid, which means all carbon-carbon bonds are single bonds. Common names for fatty acids stem from their natural sources. In addition to butyric acid, some other common saturated fatty acids include lauric acid, palmitic acid, and stearic acid. Lauric acid was first discovered in Lauraceae (Laurus nobilis) seeds, palmitic oil was prepared from palm oil, and stearic acid was discovered in animal fat and gets its name from the Greek word stear for tallow. 

Lipids are a heterogeneous group of long hydrocarbon chains that can have one of the following a free carboxyl group (fatty acids), an ester group... 

Examples of common hydrophobes include alkylphenol, fatty alcohol, paraffin, olefins, and alkylbenzene. Examples of common hydrophiles include ethylene oxide (EO), sulfates, sulfonates, phosphates, and carboxylic acid groups. Depending on the charged nature of the head group, surfactants are classified as ... 

Analogous electron transfers involving the carboxylic acid group of fatty acids (Reaction 4) or lipid oxidation products such as aldehydes (Reaction 5) (35) can also occur to form radicals that are potential initiators. Reaction 4 with free carboxylic acids has been demonstrated with cobalt and short-chain organic acids (29, 36, 37), so the potential exists for its occurrence with fatty acids. The aldehyde... 

Carboxylic (contain -COOH group) aliphatic acetic, formic aromatic benzoic, salicylic Dicarboxylic (contain two -COOH groups) oxalic, phthalic, sebacic, adipic Fatty acids (contain -COOH group) aliphatic oleic, palmitic, stearic aromatic phenylstearic... 

Synkinetic assemblies of quinones in bulk water include monolayer vesicles, where a negatively charged large quinone carboxylate is localized outside and a fatty acid carboxylate group inside. Upon addition of sodium borohydride exactly 50% of the quinone is reduced to the hydroquinone, because the borohydride anion cannot pass the membrane to react inside quinone headgroups (Scheme 7.2.6) (Fuhrhop, 1990). 

---