Fatty Acids and Related Compounds

This review is concerned with developments in the chemistry of fatty acids and of some related compounds during 1970 and 1971. 

An abbreviated form of nomenclature, widely used for long-chain acids, will be employed here. Numbers and letters are used to indicate chain-length, the number of unsaturated centres, the position(s) of unsaturation, and its nature (a, acetylenic c, c -olefinic e, ethylenic and t, /mnj-olefinic). For example, 18 2(9cl2c) is the symbol for octadeca-cw-9,c -12-dienoic acid (linoleic). Trivial names are either explained in the text or in the footnote to this page. 

Long-chain Acids.— Though new long-chain acids continue to be isolated and identified, most contain only new arrangements of familiar structural features. Acids reported here are discussed in order of increasing chain-length. Reviews 

The insect body fat of Llaveia axin is known as aje, and contains Cj2 and Cj4 acids with conjugated pentaene unsaturation. The configuration of the unsaturated system has not been determined but the structures of the two acids (1) and (2) suggest that the member is formed from the Cia acid by chain extension. 

The allenic ester produced by the male Dried Bean beetle (Acanthoscelides obtectus), with a half-life of only 10 h at room temperature or 20 days at — 13°C, has been identified as (—)-methyl tetradeca-/m/w-2,4,5-trienoate and its ( )-isomer has been synthesized.  

---

Schweizer E (1989) Biosynthesis of fatty acids and related compounds. In Ratledge C, Wilkinson SG (eds), Microbial lipids, vol. 2. Academic Press, London, p 3 -50... 

J. F. Greene, J. W. Newman, K. C. Williamson, B. D. Hammock, Toxicity of Epoxy Fatty Acids and Related Compounds to Cells Expressing Human Soluble Epoxide Hydrolase , Chem. Res. Toxicol. 2000, 13, 217 - 226. 

Acetogenins. Consistent with expectations based on the nature of the cotton plant, a number of fatty acids and related compounds have been characterized as components. Table I lists those which have been reported and which contain at least twelve carbon atoms in the linear chain. Much of such material is found in the seeds and in the waxes of the leaves and much is tied up as glyceride or as sterol ester W. Of these fatty acids, palmitic... 

The number of fatty acids and related compounds in milk lipids grew from 16 in 1959 (Jenness and Patton, 1959) to 142 in 1967 (Jensen et al. 1967) to over 400 in 1983. However, there are only 10 fatty acids of quantitative importance. The amounts (weight percent) as butyl esters prepared by three methods of esterification were determined by Iverson and Sheppard (1977). Because of the widely differing molecular weights of the fatty acids (4 0-18 0), fatty acid compositions of ruminant milk fats are often presented as a mole percent. The nutritionist needs the data calculated in yet another manner weight of fatty acid/100 g or 100 ml of edible portion. Analyses of food fatty acids should always be accompanied by the fat content so that the actual weights of the fatty acids and be calculated. A compilation of this type was made by Posati et al. (1975). Since these analyses were done with methyl esters, the contents of 4 0 are low. Data from Feeley et al. (1975), obtained from careful analyses, are more reliable, and USDA Handbook 8-1 (Posati and Orr 1976) has data for many milk and dairy products. 

The application of olefin metathesis to fatty acids and related compounds has its starting point in 1972 with the selective transformation of methyl oleate into equimolar amounts of 9-octadecene and dimethyl 9-octadecene-l,18-dioate by Van Dam, Mittelmeijer, and Boelhouwer (Scheme 1) [29]. In this early work, 1-2 mol% of a... 

In the solid phase, fatty acids and related compounds pack with the hydrocarbon chains aligned and, usually, the polar groups together. The details of the packing, such as the unit cell angles and head-to-tail or head-to-head arrangement depend on the fatty acid structure (Fig. 2). 

The most abundant products among nonionics are ethoxylated alcohols and alkylphenols, polyglycol esters of fatty acids and related compounds having polyoxyethylene chain as hydrophilic group. 

II. Acetyl-CoA (CH3COSC0A) to Fatty Acids and Related Compounds... 

As foreshadowed in Chapter 8, Scheme 8.70, it is now clear that in many species, fatty acids (and as will become apparent later, polyketide antibiotics and related materials) are derived from acetyl-CoA and, occasionally, other starter CoA (pro-panoyl,butryl, etc.) units. Overall, and in a most general sense, the assembly of fatty acids and related compounds on a polyketide synthase (PKS) enzyme begins with an acetyl (or related) starter unit (as abbreviated in Scheme 11.34) transferred to the synthase enzyme from an acetyl-CoA (or related) species (Scheme 11.35). Once attached to the enzyme synthase complex, the addition of a two-carbon unit via (what appears to be) a Claisen-type condensation takes place with a malonyl... 

Fatty Acids and Related Compounds.— Although acids are still the most... 

---