Acids, aromatic fatty

Amino acids Aromatics Fatty acids Gases... 

The term naphthenic acid, as commonly used in the petroleum industry, refers collectively to all of the carboxyUc acids present in cmde oil. Naphthenic acids [1338-24-5] are classified as monobasic carboxyUc acids of the general formula RCOOH, where R represents the naphthene moiety consisting of cyclopentane and cyclohexane derivatives. Naphthenic acids are composed predorninandy of aLkyl-substituted cycloaUphatic carboxyUc acids, with smaller amounts of acycHc aUphatic (paraffinic or fatty) acids. Aromatic, olefinic, hydroxy, and dibasic acids are considered to be minor components. Commercial naphthenic acids also contain varying amounts of unsaponifiable hydrocarbons, phenoHc compounds, sulfur compounds, and water. The complex mixture of acids is derived from straight-mn distillates of petroleum, mosdy from kerosene and diesel fractions (see Petroleum). 

Solids. —It may Idc a hydrocM bon (c .g., paraffin wa, naphthalene) highei alcohol eg., cetyl alcohol) aldehyde e.g., z5-hydroxybenzaldehyde) ketone and qiiinonc e.g., benzo-phenone, camphor) acid (higher fatty, e.g., palmitic acid or aromatic acid) ester (of glycerol, phenols or aromatic alcohols) phenol e.g., thymol),... 

The repertoire of chemicals that can be used for communication is limited by the biosynthetic ability of the insect. Compared to other insect orders, pheromone biosynthesis in Hymenoptera has received little study [191]. However, the biosynthetic origins of chemically diverse hymenopteran semiochemicals likely include aromatic, fatty acid, and terpenoid pathways as well as simple modifications of host-derived precursors. Notable recent studies include the biosynthesis of the fatty acid components (2 )-9-oxodec-2-enoic acid 52 and (2 )-9-hydroxydec-2-enoic acid of the honeybee queen mandibular pheromone from octadecanoic acid [192,193], and the aliphatic alcohol and ester... 

The factors affecting Rf include the quality of the stationary and mobile phases, the thickness and activity of the layer, and the amount of sample. Although standards may have the same Rf value as the sample, this does not uniquely identify the compound. For archaeological samples, the best identification achievable is only at a general class level (e.g., triacylglycerols, fatty acids, aromatic, or aliphatic) and not to individual molecular components. 

H2S, trace (NH3, HCN, COS, CS2, phenols, aromatics, fatty acids, tars, oxides of nitrogen and sulfur)... 

Table 9.17 shows some of the organics identified in nonurban aerosols. A wide variety of organics are found, including alkanes, alkenes, aromatics, fatty acids, alcohols, and organic bases. 

Deoxycholic acid 5-6 n-paraffins and fatty acids, aromatic molecules... 

The carboxylic acids can be subdivided into nonvolatile fatty acids, volatile fatty acids, hydroxy acids, dicarboxylic acids, and aromatic acids (Fig. 3). The nonvolatile fatty acids are molecules with more than five carbon atoms, such as stearic and palmitic acids, which are the degradation products of fats and triglycerides. Three different 18-C fatty acids that are important constituents of plants include oleic and linoleic acids that are abundant in plant seeds, and linolenic acid, which is abundant in plant leaves. Volatile fatty acids are short-chain molecules with one to five carbon atoms, such as acetic and valeric acid, associated with anaerobic metabolism. The hydroxy-acids are common intermediates in biochemical pathways, including the tricarboxylic acid cycle. The excretion of hydroxyacids by algae, such as the... 

Used for fatty acids, aromatic acids, in CH3OH herbicides, pesticides... 

Finally, the search for a strategic bond is always simplified when even a first glance analysis leads to the identification of those bonds that clearly cannot be considered strategic. The latter include bonds in aromatic rings (see, however, an exception in Vollhardt s synthesis of estrone) or heteroaromatic rings, as well as bonds which are located in readily available fragments (such as monosaccharides, amino acids, natural fatty acids, etc.). 

Elastomer compounds can be plasticized by addition of organic compounds. Elastomer compounds are inherently flexible and selection of a base polymer on the basis of molecular weight characteristics, chemical composition, and degree of crystallinity serves as the basis for the properties of the compound from which an elastomer is made. Oils are the most common plasticizer for elastomers. Oils of paraffinic structure or aromatic structure can be used with elastomers in which they are compatible. Paraffin wax would also be included in this category. Other plasticizers include phthalic acid esters and adipic acid esters. Fatty acids can be used as plasticizers but these contribute to an increase in surface tack of elastomer compounds. Examples include stearic and palmitic acid. Plasticizer addition has the added benefit of aiding with incorporation of inorganic materials. 

Preparation of Aromatic Acids.—The aromatic acids may be formed by methods which are analogous to those used in the preparation of fatty acids. Aromatic alcohols and aldehydes yield acids on oxidation —... 

Although the term N. p. is now used almost exclusively for specific organic compounds of natural origin, in the past substances of mineral origin were also included. Natural products can be classified, for example, according to a) their chemical structure e. g., alkaloids, amines, amino acids, aromatic compounds, fatty acids. 

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