18- hydroxyoleic acid

Based on the composition of the C18 family of cutin monomers we postulated that oleic acid would be > hydroxy la ted first, followed by epoxidation of the double bond at C-9 followed by the hydrolytic cleavage of the oxirane to yield 9,10,18-trihydroxy acid. This postulate was experimentally verified by the demonstration of specific incorporation of exogenous 18-hydroxyoleic acid into 18-hydroxy-9,10-epoxy C18 acid in grape berry skin slices and apple fruit skin disks, and incorporation of exogenous labeled 18-hydroxy-9,10-epoxy C18 acid into 9,10,18-trihydroxy C18 acid of cutin in apple fruit skin slices [61]. 

Cutin is composed chiefly of a C16 and/or a Cis family of monomers (Fig. 4.2). The usual components of the former are palmitic acid, 16-hydroxypalmitic acid, and 10,16-dihy-droxypalmitic and/or its positional isomers in which the midchain hydroxyl group is at C9, Cs, or C7. Monomers that could be derived from the above acids by further oxidation or reduction also have been found in cutin from some plants. The C18 family consists of stearic acid, oleic acid, linoleic acid, 18-hydroxyoleic acid, 18-hydroxy-9,10-epoxystearic acid, and 9,10,18-trihydroxystearic acid together with their A-12 unsaturated analogs. Members of the Cie family are the dominant components of the cutin of fast-growing plants, whereas the cutin of slower-growing plants with a thicker cuticle consists of a mixture of C16 and C18 monomers (Harwood, 1980). 

Hydroxyoleic acid 16-Hydroxypalmitic acid Tetradecane dicarboxylic acid... 

The by-product of this process, pelargonic acid [112-05-0] is also an item of commerce. The usual source of sebacic acid [111-20-6] for nylon-6,10 [9008-66-6] is also from a natural product, ticinoleic acid [141-22-0] (12-hydroxyoleic acid), isolated from castor oil [8001-79-4]. The acid reacts with excess sodium or potassium hydroxide at high temperatures (250—275°C) to produce sebacic acid and 2-octanol [123-96-6] (166) by cleavage at the 9,10-unsaturated position. The manufacture of dodecanedioic acid [693-23-2] for nylon-6,12 begins with the catalytic trimerization of butadiene to make cyclododecatriene [4904-61-4] followed by reduction to cyclododecane [294-62-2] (see Butadiene). The cyclododecane is oxidatively cleaved to dodecanedioic acid in a process similar to that used in adipic acid production. 

Fats and Oils. Fats and oils (6) are traditionally sulfated using concentrated sulfuric acid. These are produced by the sulfation of hydroxyl groups and/or double bonds on the fatty acid portion of the triglyceride. Reactions across a double bond are very fast, whereas sulfation of the hydroxyl group is much slower. Yet 12-hydroxyoleic acid sulfates almost exclusively at the hydroxyl group. The product is generally a complex mixture of sulfated di-and monoglycerides, and even free fatty acids. Other feeds are castor oil, fish oil, tallow, and sperm oil. 

Ricinoleic acid (dl 12-hydroxyoleic acid) [14I-22-0J M 298.5, m 7-8° (a-form), 5.0° (7-form), n 1.4717, pKe, -4.5. Purified as methyl acetylricinoleate [Rider J Am Chem Soc 53 4130 1931], fractionally distilling at 180-185°/0.3mm, then 87g of this ester was refluxed with KOH (56g), water (25mL), and MeOH (250mL) for lOmin. The free acid was separated, crystd from acetone at -50°, and distd in small batches, b 180°/0.005mm. [Bailey et al. J Chem Soc 3027 1957.]... 

The important but unusual fatty acid ricinoleic acid, or 12-hydroxyoleic acid, is a major component of castor oil (>87%) and is also found in useful quantities in ergot. The metal salts of the acid find use in dry-cleaning soaps but the majority is converted to aminoundecanoic acid (Scheme 6.6) which is used to make nylon 11. Nylon 11 has very good chemical and shock-resistance properties, which have led to it being used in the automotive industry. Ricinoleic triglyceride is initially transesterified to the methyl ester. This is heated to 300 °C at which temperature it is... 

Castor oil [CO Structure (4.3)] is a triglyceride of ricinoleic (12-hydroxyoleic) acid about 90% of the fatty acid portion of the molecule consists of ricinoleic acid and 10% in the form of non-hydroxy acids consisting largely of oleic and linoleic acids. Small amounts of stearic and dihydroxystearic acids are also found in some industrial grades. 

This reagent does not react with double bonds, as demonstrated when fluorooleic acids were prepared from the corresponding hydroxyoleic acids and incorporated by enzymes into living cells163. Acetylenes do not react with DAST either, but ynones do and produce difluoroacetylenes164. The reaction was used by Kobayashi and coworkers to prepare difluoroleukotriene 16 with similar biological effects to arachidonic acid (equation 91)165. 

Hydroxy and Epoxy Acid Group Although a number of oils contain acids with hydroxy, epoxy, or oxo (keto) functions, only one is readily available. Castor oil contains over 90% of ricinoleic acid (12-hydroxyoleic acid) and about 1% of 9,10-dihydroxystearic acid (section 5.1). 

CH3(CH2)5CH0HCH2CH=CH(CH2)7C00H ricinoleic acid (12-hydroxyoleic acid)... 

Castor Oil and Transesterification Derivatives of Castor Oil and Other Oils. Castor oil, consisting mainly of a triglyceride of ricinoleic (12-hydroxyoleic) acid (90% ricinoleic acid, 10% nonhydroxy acids, largely oleic and linoleic acids), is a frequent hydroxyl component of urethane coatings. On the basis of the hydroxyl number, castor oil is 70% trifunctional and 30% difunctional. The presence of castor oil in urethane polymers... 

Hydroxy-5-t-octylphenyl) benzotriazole 2-(2-Hydroxy-5-t-octylphenyl) benzotriazole. See Octrizole 12-Hydroxyoleic acid d-12-Hydroxyoleic acid. See Ricinoleic acid... 

CAS 141-22-0 EINECS/ELINCS 205-470-2 Synoryms Castor oil acid 12-Hydroxy-9-octadecenoic acid 12-Hydroxy-cis-9-octadecenoic acid cis-12-Hydroxyoctadec-9-enoic acid 12-Hydroxyoleic acid d-12-Hydroxyoleic acid 9-Octadecenoic acid, 12-hydroxy- Oleic acid, 12-hydroxy- Ricinic acid Ricinolic acid Classification Unsaturated fatty acid Empirical CisHsjOs... 

Hydroxyoleic acid d-12-Hydroxyoleic acid. See Ricinoleic acid... 

R)-12-Hydroxyoleic acid, monoester with 1,2-propanediol. See Propylene glycol ricinoleate y-Hydroxy-P-oxobutane. See Acetyl methyl carbinol... 

Yet other hydroxy acids have their hydroxyl group at or near the methyl end of the chain. Hydroxy acids (see also polyhydroxy acids later in this section) are frequently present in waxes (Section 2.10) and in the (polymerized) cutins and suberins (Section 2.11). Yeasts frequently generate tt>2-hydroxy acids as glycosides within their extracellular hpids. (5)-17-l-hydroxystearic and (5)-17-L-hydroxyoleic acids are the best known examples. 

Dehydration by heating (230-280 °C) under vacuum with a suitable catalyst (e.g. mineral acids or acid clays) converts the hydroxyoleic acid to a mixture of geometric and positional isomers of oc-tadecadienoic acid, both conjugated and non conjugated (Achaya, 1971 Body and Shorland, 1965 Von Mikusch, 1955). 

It should be noted that a few hydroxylations occur without a mixed-funtion oxidase enzyme. For example, the ergot fungus Claviceps purpurea forms 12-hydroxyoleic acid (ricinoleic) by hydration of linoleic acid (Harwood and Russell, 1984). 

Hydroxyoct-2-enal, 457 2-Hydroxyoleic acid, 19 17-Hydroxyoleic acid, 20 Hydroxysphinganine, 32, 519 17-Hydroxystearic acid, 20 2-Hydroxysterculic acid, 17, 53 Hyperlipoproteinemias, 538 Hyphae, 151... 

The most common substituted fatty acids found in plants are the monohy droxy derivatives, though polyhydroxy acids, keto acids, epoxy acids, di-carboxylic acids and even to-fluoro acids (Ward et al., 1964) are known. The 2-hydroxy derivatives of common fatty acids are found esterified in cerebro-sides, ceramides, and phytoglycolipid in high amounts. In seed oils they occur in triacylglycerol. All known 2-hydroxy acids are d isomers. The 3-hydroxy acids, which are important intermediates in both fatty acid synthetase and )8-oxidation pathways, rarely accumulate. However, ricinoleic (12-hydroxyoleic) acid accounts for 90% of the fatty acids of commercial... 

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