11-Methyl-12-octadecenoic acid

Two rather interesting racemic syntheses for allylic methylated fatty acids have been recently accomplished [15]. One of these corresponds to the intriguing (12 )-11-methyl-12-octadecenoic acid (6), a marine bacterial fatty acid that in most reported identifications from natural sources has been shown to have the E double bond stereochemistry, but both Z,E isomers have been synthesized [15]. This mainly bacterial fatty acid was initially isolated from Byrsocarpus coccineus seed oil [16], but later it was reported in a bacterium associated with cat scratch disease [17], in Mycobacterium fallax [18], and most recently in a Pseudomonas sp. (.Alteromonas) associated with both the toxic dinoflagellate Ostreopsis lenticularis and several Caribbean Palythoa species [15]. More recently, acid 6 has been identified as an intermediate in the biosynthesis of the bacterial acid 10,13-epoxy-l l-methyloctadeca-10,12-dienoic acid, a furan fatty acid identified in several marine bacteria such as Shewanella putrefaciens [19-20]. 

Fig. (6). Total synthesis of racemic 11-methyl-12-octadecenoic acid (6)...

Figure 11.1 Py/methylation GC/MS chromatograms of lead white pigmented linseed oil paint after 610 °C Curie point pyrolysis assisted with on line methylation using 2.5% methanolic TMAH (the sample and TMAH solution was applied onto a rotating Curie point wire pyrolysis time 6 s, interface 180°C). 1, heptenoic acid, methyl ester 2, heptanoic acid, methyl ester 3, butenedioic acid, dimethyl ester 4, butanedioic acid, dimethyl ester 5, octenoic acid, methyl ester 6, octanoic acid, methyl ester 7, pentenedioic acid, dimethyl ester 8, pentanedioic acid, dimethyl ester 9, nonanoic acid, methyl ester 10, hexanedioic acid, dimethyl ester 11, decanoic acid, methyl ester 12, heptanedioic acid, dimethyl ester 13, octanedioic acid, dimethyl ester 14, 1,2 benzenedicarboxylic acid, dimethyl ester 15, a methyl octanedioic acid, dimethyl ester 16, nonanedioic acid, dimethyl ester 17, a methoxy octanedioic acid, dimethyl ester 18, a methyl nonanedioic acid, dimethyl ester 19, a,a dimethyl nonenedioic acid, dimethyl ester 20a, a methyl nonenedioic acid, dimethyl ester 20b, a,a dimethyl nonanedioic acid, dimethyl ester 21, decanedioic acid, dimethyl ester 22, a methoxy nonanedioic acid, dimethyl ester 23, a methyl decan edioic acid, dimethyl ester 24, undecanedioic acid, dimethyl ester 25, a methoxy decan edioic acid, dimethyl ester 26, pentadecanoic acid, methyl ester 27, dodecanedioic acid, dimethyl ester 28, hexadecanoic acid, methyl ester 29, heptadecanoic acid, methyl ester 30, octadecanoic acid, methyl ester 31,8 methoxy 9 octadecenoic acid, methyl ester 32, 11 methoxy 9 octadecenoic acid, methyl ester 33, 9 methoxy 10 octadecenoic acid and 10 methoxy 8 octadecenoic acid 34, 9 oxo octadecanoic acid, 10 oxo octadecanoic acid 35, 9 epoxy octadecanoic acid 36, eicosanoic acid, methyl ester 37, 9,10 dimethoxy octadecanoic acid, methyl ester 38, docosanoic acid, methyl ester. Reprinted from J. Anal. Appl. Pyrol., 61, 1 2, van den Berg and Boon, 19, Copyright 2001, with permission from Elsevier...

TLC spots with marker reveal the presence of free fatty acids (FFA), diglyceride (DG), monoglyceride (MG) but negligible amount of TG. GCMS of fatty acid— methyl esters (FAME) from lion mane presented evidence for fatty acids ranging from C9-C24 (Figs. 5.3- 5.6). Low volatility molecules like nonanedioic acid (Fig. 5.3), tridecanoic acid (Fig. 5.4), 12-methyl tridecanoic acid were also present in lion hair lipids. In addition fatty acids such as myristic, pentadecanoic, palmitic, heptanoic, stearic and octadecenoic acids (Fig. 5.5) have also been detected. Erucic... 

Figure 12.1 Fatty acid carbon numbering system. The carbon atoms are numbered in sequence with the carboxyl carbon atom as number 1. By this system the terminal methyl carbon of oleic (octadecenoic) acid is number 18. An older system names this methyl carbon as the o-carbon and the adjacent carbon atom as number 2. Numbering then continues towards the carboxyl carbon and values are given for n to denote the number of carbon atoms from the o-carbon to any double bonds. See Table 12.3.

The indole 22 was previously isolated from the sponge Dysidea etheria [110] and has now been obtained from the Antarctic ice bacterium ARK 13-2-437. The lipid phase of Hel45 delivered additionally N-(2-hydroxyethyl)-ll-octadecen-amide and the new natural products 17-methyl-16-octadecenoic acid [95] and indole-3-carboxylic acid thiomethyl ester (23). 

Quantitative changes in lipid compounds on the silk and cuticle of females correlate significantly with changes in female sexual receptivity in spiders. For example, female T. atrica attach a contact sex pheromone to their web (Trabalon et al., 1997,2005 Prouvost et al., 1999). This pheromone consists of a complex mixture of saturated hydrocarbons, methyl esters (methyl tetradecanoate, methyl pentadecanoate, methyl hexadecanoate, and methyl octadecanoate) and their fatty acids (tetradecanoic, pentadecanoic, hexadecanoic, and cis,cis-9,12-octadecadienoic acids). The female uses cuticular compounds, which are applied to the silk in substantial amounts during web construction. Modification of chemical profiles makes the female attractive to males (Trabalon et al., 2005). Receptive females are different to unreceptive ones with respect to three fatty acids (hexadecanoic, octadeca-dienoic and octadecenoic acids) and three methyl esters (linoleate, oleate, and stearate) present on both the web and the cuticle. Our combined results from chemical analyses and behavioral assays demonstrate clearly that these contact compounds are quantitatively correlated with the behavior of spiders. 

The methyl esters obtained are readily analysed qualitatively and quantitatively by gas chromatography, and the data obtained allow detection of sophistication. In the literature there is a wealth of fatty acid analysis data on virgin olive oils, all constantly reporting almost the same qualitative composition. However, what is surprising is the systematic attitude of so many researchers not reporting the presence of vaccenic acid, 11 -ds-octadecenoic acid, an isomer of oleic acid. The presence of this positional isomer of oleic acids was first described in olive oil by Tulloch and Craig (1964). 

A. Nonalkaloidal, 0.35, 198°C, m/z 265(50), 264(100), 222(58), 180(72). This proved to be octadecenoic acid methyl ester with a true parent ion of m/z 296. Fatty acid methyl esters do not afford a major protonated parent ion with NH3 chemical ionization-mass spectrometry. Such fatty acid methyl esters frequently represent trace contaminants of alkaloid fractions. 

Isohexyl alcohol 1-Pentanol, 4-methyl- Oleic acid 9-Octadecenoic acid, (Z)-... 

SYNS EMEREST2301 ExMEREST2801 EMERY 2219 EMERY 2310 EMERY OLEIC ACID ESTER 2301 KEMESTER 105 KEMESTER 115 0 KEMESTER 205 KEMESTER 213 METHYL-9-OCTADECENOATE METHYL ds-9-OCTADECENOATE METHYL (Z)-9-OCTADECENOATE METHYL OLEATE (Z)-9-OCTADECENOIC ACID METHYL ESTER... 

OCTADECANOL see OAXOOO n-OCTADECANOL see OAXOOO 9,10-OCTADECENOIC ACID see OHUOOO cis-OCTADEC-9-ENOIC ACID see OHUOOO cis-9-OCTADECENOIC ACID see OHUOOO ds-A -OCTADECENOIC ACID see OHUOOO 9-OCTADECENOIC ACID CALCIUTM SALT see CAU300 (Z)-9-OCTADECENOIC ACID METHYL ESTER see OHWOOO... 

Fatty acids with trans or non-methylene-interrupted unsaturation occur naturally or are formed during processing for example, vaccenic acid (18 1 Hr) and the conjugated linoleic acid (CLA) rumenic acid (18 2 9tllc) are found in dairy fats. Hydroxy, epoxy, cyclopropane, cyclopropene acetylenic, and methyl branched fatty acids are known, but only ricinoleic acid (12(/f)-hydroxy-9Z-octadecenoic acid) (2) from castor oil is used for oleochemical production. OUs containing vernolic acid (12(5),13(/ )-epoxy-9Z-octadecenoic acid) (3) have potential for industrial use. 

Synonyms methyl 9-octadecenoate (Z)-9-octadecenoic acid, methyl ester. 

Synonyms (Z)-9-Octadecenoic acid methyl ester Oleic acid methyl ester... 

Synonyms (Z)-9-Octadecenoic acid methyl ester Oleic acid methyl ester Source Nilsson, W. B. Gauglitz, E. J. Jr. Hudson, J. K. J. Am. OilChem. Soc. (1991), 68(2), 87-91. 

EINECS 205-392-9 Flexricin P-4 Flexricin P-4 Methyl 12-acetoxy-9-octadecenoate Methyl 12-acetoxyoleate Methyl acetyl ricinoleate Methyl 0-acetylricinoleate Methyl ricinoleate, acetate Methylester kyseliny acetyiricinolejove NSC 2398 9-Octadecenolc acid, 12-(acetyloxy)-, methyl ester 9-Octadecenoic acid, 12-(acetyloxy)-, methyl ester, (9Z.12R)- 9-Octadecenoic acid, 12-(ace loxy)-, methyl ester, (R-(Z))- (9CI) Ricinoleic acid, methyl ester, acetate Ricinoleic acid, methyl ester, acetate Methyl 12-acetoxy-9-octadecenoate. All purpose plasticizer, lubricant for vinyls and lacquers. Liquid mp = -16 d = 0.938 soluble in most organic solvents insoluble in water LDso (mus orl) = 34,900 mg/kg. CasChem. 

Octadecenoic acid (9Z)-, ester vrith 2-ethyl-2-(hydroxy-methyl)-... 

Ethyl-2-(((1-oxooleyl)oxy)methyl)-1,3-propanediyldioleate. EINECS 260-895-0 2-Ethyl-2-(((1-oxooleyl)oxy)methyl)-1,3-propanediyl dioleate 9-Octadecenoic acid (9Z)-, 2-ethyl-2- (( 9Z)-1-oxo-9-octadecenyl)oxy)methyl)-1,3-prop-anediyl ester ... 

A novel two carbon analog of 8, namely the 7-methyl-6(Z)-octadecenoic acid was recently identified in the holothurian Holothuria mexicana [27]. However, both Z and E stereoisomers were later shown to originate from the bacterium Vibrio alginolyticus [27]. Therefore, the real source of 7-methyl-6-octadecenoic acid is also bacterial. Both Z and E isomers of 7-methyl-6-octadecenoic acid were synthesized as shown in Fig. (9). In this short synthesis (little more than one step) a Wittig coupling of (6-carboxyhexyl)triphenylphosphonium bromide with 2-tridecanone readily afforded a 1 1 mixture of 7-methyl-6(Z)-octadecenoic... 

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