Preparation and reactions of fatty acid azirines

The 1-azirine derivatives ofcis-9-octadecene and methyl oleate have been prepared, and some of their reactions have been studied. The preparation of these novel fatty acid derivatives was accomplished in a three-step synthesis with good overall yields. Addition of the electrophile IN₃ to the olefin yielded the β-iodoazide derivatives of octadecane and stearic acid. Treatment of the latter compounds with base resulted in dehydrohalogenation and gave the vinyl azides. Solution photolysis of the vinyl azides yielded the 1-azirine derivatives. Reduction of the 1-azirines with metal hydrides gave the known epimino derivatives of octadecane and octadecanol. Other reducing agents were unsuccessful in preserving the three-membered ring. Reaction with acids caused the dimerization of the 1-azirines with formation of tetrasubstituted pyrazines. The 1-azirines were attacked by acid chlorides and hydrochloric acid to give chlorinated amides as principal products. Presented at the AOCS Meeting, Atlantic City, October 1971. E. Market. Nutr. Res. Div., ARS, USDA.     

An epoxy alcohol synthase pathway in higher plants: Biosynthesis of antifungal trihydroxy oxylipins in leaves of potato

[1-¹⁴C]Linoleic acid was incubated with a whole homogenate preparation of potato leaves (Solanum tuberosum 1., var. Bintje). The methyl-esterified product was subjected to straight-phase high-performance liquid chromatography and was found to contain four major radioactive oxidation products, i.e., the epoxy alcohols methyl 10(S), 11(S)-epoxy-9(S)-hydroxy-12(Z)-octadecenoate (14% of the recovered radioactivity) and methyl 12(R), 13(S)-epoxy-9(S)-hydroxy-10(E)-octadecenoate (14%), and the trihydroxy derivatives methyl 9(S), 10(S), 11(R)-trihydroxy-12(Z)-octadecenoate (18%) and methyl 9(S), 12(S), 13(S)-trihydroxy-10(E)-octadecenoate (30%). The structures and stereochemical configurations of these oxylipins were determined by chemical and spectral methods using the authentic compounds as references. Incubations performed in the presence of glutathione peroxidase revealed that lipoxygenase activity of potato leaves generated the 9- and 13-hydroperoxides of linoleic acid in a ratio of 95∶5. Separate incubations of these hydroperoxides showed that linoleic acid 9(S)-hydroperoxide was metabolized into epoxy alcohols by particle-bound epoxy alcohol synthase activity, whereas the 13-hydroperoxide was metabolized into α- and γ-ketols by a particle-bound allene oxide synthase. It was concluded that the main pathway of linoleic acid metabolism in potato leaves involved 9-lipoxygenase-catalyzed oxygenation into linoleic acid 9(S)-hydroperoxide followed by rapid conversion of this hydroperoxide into epoxy alcohols and a slower, epoxide hydrolase-catalyzed conversion of the epoxy alcohols into trihydroxyoctadecenoates. Trihydroxy derivatives of linoleic and linolenic acids have previously been reported to be growth-inhibitory to plant-pathogenic fungi, and a role of the new pathway of linoleic acid oxidation in defense reactions against pathogens is conceivable.     

The cyanoethylation and infrared spectra of some ricinoleic acid derivatives

Summary Five ricinoleic acid derivatives have been cyanoethylated with acrylonitrile, namely, 4-ricinoleoylmorpholine, 4-ricinelaidoylmorpholine, 4-(12-hydroxystearoyl) morpholine, 1,12-dihydroxy-9-octadecene and 1,12-dihydroxyoctadecane, using benzyltrimethylammonium hydroxide as a cyanoethylation catalyst and water to retard the polymerization of acrylonitrile. Any polyacrylonitrile formed was readily precipitated out of an ethereal solution. Purification of the cyanoethylated products was accomplished by washing out the catalyst, rapid distillation under high vacuum, and crystallizations from methanol. In addition, 1,12-bis(β-cyanoethoxy)-9-octadecene was isomerized fromcis totrans form and crystallized successively from acetone and methanol. The infrared spectra of these compounds have been determined. It was found that the characteristic absorption for the nitrile group at 4.44 microns is about 67% greater in chloroform than in carbon tetrachloride and that it obeys Beer's law over a wide range of concentrations, thus permitting convenient infrared analysis of this type of compound. Some properties of these compounds are described. Presented at the 50th annual meeting, American Oil Chemists' Society, New Orleans, La., April 20–22, 1959. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

High-performance liquid chromatography and spectroscopic studies on fish oil oxidation products extracted from frozen atlantic mackerel

The formation of stable hydroxy derivatives from hydroperoxides produced during the oxidation of linoleic acid methyl ester and fish oil were studied by reverse-phase high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS) and ¹³C nuclear magnetic resonance (NMR) spectroscopy. The oxidation products identified were mixtures of four isomeric hydroxy derivatives: 13-hydroxy-9-cis,11-trans-octadecadienoic, 13-hydroxy-9-trans,11-trans-octadecadienoic, 9-hydroxy-10-trans,12-cis-octadecadienoic, and 9-hydroxy-10-trans,12-trans-octadecadienoic acids. The presence of hydroxy compounds was confirmed by ¹³C NMR, which gave rise to a hydroxy carbon peak at 87 ppm, and by GC-MS, which showed three peaks corresponding to isomeric mixtures of trimethylsilyl ethers of the oxidized linoleic acid methyl ester. The mass spectra scans of the three peaks showed that they represent isomers of molecular weight 382 and are consistent with the molecular formula C₂₂H₄₂O₃Si. In oil extracted from stored frozen mackerel, 13-hydroxy-9-cis,11-trans-octadecadienoic acid was more prominent compared to the model lipid systems. HPLC offered a sensitive means of detection of hydroxy compounds produced both in the initiation and latter stages of oxidation. The effect of antioxidants added to the fish mince prior to storage can also be monitored by HPLC. Thus, the monitoring of lipid oxidation hydroxy derivatives by HPLC is of practical value in the efficient processing and quality control of fish, fish oils, and other fatty foodstuffs in order to enhance the acceptability, nutritional, and safety aspects.     

Identification of (e)-11-hydroxy-9-octadecenoic acid and (E)-9-hydroxy-10-octadecenoic acid by biotransformation of oleic acid by Pseudomonas sp. 32T3

Pseudomonas sp. 32T3, a newly identified strain originally isolated from a vegetable oil-contaminated soil, produces three monohydroxy acids—(E)-11-hydroxy-9-octadecenoic acid, (E)-10-hydroxy-8-octadecenoic acid, and (E)-9-hydroxy-10-octadecenoic acid—as bioconversion products of oleic acid. The bacterial cells were grown in a mineral medium containing oleic acid as the main carbon substrate. The compounds were identified as the corresponding methyl esters on the basis of their chromatographic and spectroscopic (¹H and ¹³C nuclear magnetic resonance and gas chromatography-mass spectrometry) features.     

Reaction of amines with conjugated olefins using lithium naphthalenide in non-ethereal solvents

It was found that lithium naphthalenide can be prepared from metallic lithium cuttings and naphthalene in non-ethereal solvents, such as benzene–N,N,N′,N′-tetramethylethylenediamine (TMEDA) or benzene-N,N,N′,N′-tetramethyldiaminopropane (TMDAP), under ultrasonic irradiation. Secondary amines reacted with conjugated olefins, such as isoprene or myrcene, using lithium naphthalenide in such non-ethereal solvents to give allylic amines. The yields of products were higher than in the reaction using lithium naphthalenide in tetrahydrofuran. From diethylamine (I) and isoprene (II), a mixture of N,N-diethyl-3-methyl-2-butenylamine (IV) and N,N-diethyl-2-methyl-2-butenylamine (V) (IV:V = 79:21) was obtained in 77% yield, and from diethylamine (I) and myrcene (III), N,N-diethylgeranylamine (VI) and N,N-diethylnerylamine (VII) (VI:VII = 88:12) were produced in 72% yield. These terpenic amines, VI and VII, are used as starting compounds for the preparation of perfumery materials.     

Biotransformation of linoleic acid by Clavibacter sp. ALA2: Heterocyclic and heterobicyclic fatty acids

Clavibacter sp. ALA2 transformed linoleic acid into a variety of oxylipins. In previous work, three novel fatty acids were identified, (9Z)-12,13,17-trihydroxy-9-octadecenoic acid and two tetrahydrofuran-(di)hydroxy fatty acids. In this report, we confirm the structures of the tetrahydrofuran-(di)hydroxy fatty acids by nuclear magnetic resonance as (9Z)-12-hydroxy-13,16-epoxy-9-octadecenoic acid and (9Z)-7,12-dihydroxy-13,16-epoxy-9-octadecenoic acid. Three other products of the biotransformation were identified as novel heterobicyclic fatty acids, (9Z)-12,17;13,17-diepoxy-9-octadecenoic acid, (9Z)-7-hydroxy-12,17;13,17-diepoxy-9-octadecenoic acid, and (9Z)-12,17;13,17-diepoxy-16-hydroxy-9-octadecenoic acid. Thus, Clavibacter ALA2 effectively oxidized linoleic acid at C-7,-12,-13,-16, and/or-17.     

Synthesis of fatty 2-oxazolines from fatty methyl 2,3-epoxy ester

Reaction of methyltrans-2,3-epoxyhexadecanoate (I) with benzonitrile in presence of boron trifluoride-etherate (BF₃-etherate) as catalyst has yieldedcis-2-phenyl-4-tridecyl-5-carbomethoxy-2-oxazoline (II), methyl 2-hydroxy-3-benzamidohexadecanoate (IV) and methyl 2,3-dihydroxyhexadecanoate (III). On the other hand, reactions of I with acetonitrile and acrylonitrile have resulted in the formation of their corresponding hydroxyamides, methyl 2-hydroxy-3-acetamidohexadecanoate (VI) and methyl 2-hydroxy-3-acryloamido hexadecanoate (VII), respectively, along with the product (III) only. Pyrolysis of hydroxyamides (IV), (VI) and (VII) afforded their corresponding 2-oxazolines,cis-2-phenyl-4-tridecyl-5-carboxy-2-oxazoline (V),cis-2-methyl-4-tridecyl-5-carboxy-2-oxazoline (VIII) andcis-2-vinyl-4-tridecyl-5-carboxy-2-oxazoline (IX), respectively, in good yields. The products have been characterized with the help of spectral and microanalyses. Presented at the 4th Annual Convention of the Indian Council of Chemists held in December 1984 at Gorakhpur University, India.     

Synthesis of 4,4′-aryldihydrazono-3-(3′-pyridyl)-2-pyrazolin-4,5-diones and 1-aryl-3-(3′-pyridyl)-4,4′-arylbisazo-5-aryliminopyrazoles and their application as disazo disperse dyes. Part II

3-(3′-Pyridyl)-2-pyrazoline-4,5-dione 4,4′(4,4′-biphenylenedihydrazone and p-phenylenedihydrazone) and its derivatives ( IIa-e, IIIa-e ) were obtained by the coupling reaction of tetrazotised benzidine and p-diamonobenzene with 3-(3′-pyridyl)-2-pyrazolin-5-ones ( Ia-e ). Similarly, bis-azo compounds containing pyrazole nucleous as, 1-aryl-3-(3′-pyridyl)-4,4′-arylbisazo-5-aryliminopyrazoles ( VIa-i and VIIa-i ) were prepared by the interaction of the corresponding chloro compound ( IV and V ) with aromatic amines. The compounds so obtained ( II, III, VI and VII ) are used as disazo disperse dyes for dyeing polyester fibres fast yellow-orange shades. Their fastness properties towards washing, rubbing, acid-alkaline perspiration and light were investigated.     

Reaction of long chain triol acids with hydrogen bromide

The reaction of hydrogen bromide (HBr) with long chain triol acids has been investigated in some detail. The 9, 10, 12-trihydroxy stearic acid (I) on treatment with HBr yielded three products, namely 9(10)-bromo-10(9)-hydroxy-12-bromo (III), 9(10)-bromo-10(9)acetoxy-12-bromo (IV) and 9,10-dibromo-12-hydroxy (V) stearic acids. When 9,12,13-trihydroxy stearic acid (II) was subjected to the same reaction under similar conditions, 12,13-dibromo-9-hydroxy (VI), 12(13)-bromo-13(12) acetoxy-9-bromo (VII) stearic acids were obtained. The structure of these products were established on the basis of their elemental values, spectral data and chemical evidence.     

Iodoazide addition to olefinic esters and their reaction with methanolic KOH

Addition of iodine azide to methyl 10-undecenoate (1), methyl oleate/elaidate (III,IV) and methyltrans-2-hexadecenoate (VII) yielded methyl 10-azido-11-iodoundecanoate (II, ∼ 100%), methylerythro/threo-9(10)-azido-10(9)-iodooctadecanoate (V,VI) and methylerythro-3-azido-2-iodohexadecanoate (VIII), respectively. The reaction of iodoazide adduct (II) with methanolic KOH yielded 10-azidoundec-10-enic acid (IX) and 10-oxoundecanic acid (X), while V and VI gave a mixture of 9(10)-oxooctadecanoic acid (XI). Adduct VIII, under the identical condition after esterification, gave 3 products, methyl 4-methoxy-trans-2-hexadecenoate (XII), 2-oxopentadecane (XIII) and methyl 3-methoxyhexadecanoate (XIV). The unusual behavior of VIII can be tentatively attributed to the role of adjacent carbonyl on the expected elimination of HI by methanolic alkali.     

Analysis of seed oil from ricinus communis and dimorphoteca pluvialis by gas and supercritical fluid chromatography

The seed oils from Dimorphoteca pluvialis and Ricinus communis contain hydroxy fatty acids. Dimorphoteca pluvialis contains Δ-9-hydroxy-10t, 12t-octadecadienoic acid (dimorphecolic acid) and R. communis contains Δ-12-hydroxy-9c-octadecenoic acid (ricinoleic acid). The oils were derivatized and analyzed to determine the content of hydroxy fatty acids. The trimethylsilyl fatty acid methyl ester (TMS-FAME) derivatives were analyzed by capillary gas chromatography (GC), and the free fatty acid (FFA) derivatives and the oils were analyzed by capillary supercritical fluid chromatography (SFC). Further, mass spectroscopy of the TMS-FAME derivatives was performed to check the purity of the derivatives. The results from the GC analyses of TMS-FAME corresponded to the results found by SFC analysis of the FFA. The content of ricinoleic acid in the glycerolipids of R. communis was 87.7 wt%, and the content of dimorphecolic acid in D. pluvialis was 54.0 wt%. The methods were evaluated with respect to the cost, ease, and time needed for sample preparation and analysis.     

Homolytic decomposition of linoleic acid hydroperoxide: Identification of fatty acid products

An isomeric mixture of linoleic acid hydroperoxides, 13-hydroperoxy-cis-9,trans-11-octadecadienoic acid (79%) and 9-hydroperoxy-cis-12,trans-10-octadecadienoic acid (21%), was decomposed homolytically by Fe(II) in an ethanol-water solution. In one series of experiments, the hydroperoxides were decomposed by catalytic concentrations of Fe(II). The 10⁻⁵ M Fe(III) used to initiate the decomposition was kept reduced as Fe(II) by a high concentration of cysteine added to the reaction in molar excess of the hydroperoxides. Nine different monomeric (no detectable dimeric) fatty acids were identified from the reaction. Analyses of these fatty acids revealed that they were mixtures of positional isomers identified as follows: (I) 13-oxo-trans,trans-(andcis,trans-) 9,11-octadecadienoic and 9-oxo-trans,trans- (andcis,trans-) 10,12-octadecadienoic acids; (II) 13-oxo-trans-9,10-epoxy-trans-11-octadecenoic and 9-oxo-trans-12, 13-epoxy-trans-10-octadecenoic acids; (III) 13-oxo-cis-9,10-epoxy-trans-11-octadecenoic and 9-oxo-cis-12, 13-epoxy-trans-10-octadecenoic acids; (IV) 13-hydroxy-9,11-octadecadienoic and 9-hydroxy-10,12-octadecadienoic acids; (V) 11-hydroxy-trans-12, 13-epoxy-cis-9-octadecenoic and 11-hydroxy-trans-9, 10-epoxy-cis-12-octadecenoic acids; (VI) 11-hydroxy-trans-12, 13-epoxy-trans-9-octadecenoic and 11-hydroxy-trans-9,10-epoxy-trans-12-octadecenoic acids; (VII) 13-oxo-9-hydroxy-trans-10-octadecenoic acids; (VIII) isomeric mixtures of 9, 12, 13-dihydroxyethoxy-trans-10-octadecenoic and 9, 10, 13-dihydroxyethoxy-trans-11-octadecenoic acids; and (IX) 9, 12, 13-trihydroxy-trans-10-octadecenoic and 9, 10, 13-trihydroxy-trans-11-octadecenoic acids. In another experiment, equimolar amounts of Fe(II) and hydroperoxide were reacted in the absence of cysteine. A large proportion of dimeric fatty acids and a smaller amount of monomeric fatty acids resulted. The monomeric fatty acids were examined by gas liquid chromatography-mass spectroscopy. Spectra indicated that the monomers were largely similar to those produced by the Fe(III)-cysteine reaction. Presented in part at the American Chemical Society Meeting, Los Angeles, March 1974. ARS, USDA.     

Transformation of fatty acid hydroperoxides by alkali and characterization of products

It has previously been determined that (13S,9Z,11E)-13-hydroperoxy-9,11-octadecadienoic acid was mainly converted into (13S,9Z,11E)-13-hydroxy-9,11-octadecadienoic acid by 5 N KHO with preservation of the stereochemistry of the reactant [Simpson, T.D., and Gardner, H.W. (1993)Lipids 28, 325–330]. In addition, about 20–25% of the reactant was converted into several unknown by-products. In the present work it was confirmed that the stereochemistry was conserved during the hydroperoxy-diene to hydroxydiene transformation, but also, novel by-products were identified. It was found that after only 40 min reaction (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid accumulated to as much as 7% of the total. Later, (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid began to disappear, and several other compounds continued to increase in yield. Two of these compounds, 2-butyl-3,5-tetradecadienedioic acid and 2-butyl-4-hydroxy-5-tetradecenedioic acid, were shown to originate from (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid, and they accumulated up to 2–3% each after 4 to 6 h. Some other lesser products included 11-hydroxy-9,12-heptadecadienoic acid, 3-hydroxy-4-tridecenedioic acid, 13-oxo-9,11-octadecadienoic acid and 12,13-epoxy-11-hydroxy-9-octadecenoic acid. Except for the latter two, most or all of the compounds could have originated from Favorskii rearrangement of the early product, (9Z)-13-oxo-trans-11,12-epoxy-9-octadecenoic acid, through a cyclopropanone intermediate.     

Metabolic profile of linoleic acid in stored apples: Formation of 13(R)-hydroxy-9(Z),11(E)-octadecadienoic acid

During our ongoing project on the biosynthesis of R-(+)-octane-1,3-diol the metabolism of linoleic acid was investigated in stored apples after injection of [1-¹⁴C]-, [9,10,12,13-³H]-, ¹³C₁₈- and unlabeled substrates. After different incubation periods the products were analyzed by gas chromatography-mass spectroscopy (MS), high-performance liquid chromatography-MS/MS, and HPLC-radiodetection. Water-soluble compounds and CO₂ were the major products whereas 13(R)-hydroxy- and 13-keto-9(Z),11(E)-octadecadienoic acid, 9(S)-hydroxy-and 9-keto-10(E),12(Z)-octadecadienoic acid, and the stereoisomers of the 9,10,13- and 9,12,13-trihydroxyoctadecenoic acids were identified as the major metabolites found in the diethyl ether extracts. Hydroperoxides were not detected. The ratio of 9/13-hydroxy- and 9/13-keto-octadecadienoic acid was 1∶4 and 1∶10, respectively. Chiral phase HPLC of the methyl ester derivatives showed enantiomeric excesses of 75% (R) and 65% (S) for 13-hydroxy-9(Z),11(E)-octadecadienoic acid and 9-hydroxy-10(E),12(Z)-octadecadienoic acid, respectively. Enzymatically active homogenates from apples were able to convert unlabeled linoleic acid into the metabolites. Radiotracer experiments showed that the transformation products of linoleic acid were converted into (R)-octane-1,3-diol. 13(R)-Hydroxy-9(Z), 11(E)-octadecadienoic acid is probably formed in stored apples from 13-hydroperoxy-9(Z),11(E)-octadecadienoic acid. It is possible that the S-enantiomer of the hydroperoxide is primarily degraded by enzymatic side reactions, resulting in an enrichment of the R-enantiomer and thus leading to the formation of 13(R)-hydroxy-9(Z),11(E)-octadecadienoic acid.     

New cyclopentenone fatty acids formed from linoleic and linolenic acids in potato

[1-¹⁴C]Linoleic acid was incubated with a whole homogenate preparation from potato stolons. The reaction product contained four major labeled compounds, i.e., the α-ketol 9-hydroxy-10-oxo-12(Z)-octadecenoic acid (59%), the epoxy alcohol 10(S),11(S)-epoxy-9(S)-hydroxy-12(Z)-octadecenoic acid (19%), the divinyl ether colneleic acid (3%), and a new cyclopentenone (13%). The structure of the last-mentioned compound was determined by chemical and spectral methods to be 2-oxo-5-pentyl-3-cyclopentene-1-octanoic acid (trivial name, 10-oxo-11-phytoenoic acid). Steric analysis demonstrated that the relative configuration of the two side chains attached to the five-membered ring was cis, and that the compound was a racemate comprising equal parts of the 9(R), 13(R) and 9(S), 13(S) enantiomers. Experiments in which specific trapping products of the two intermediates 9(S)-hydroperoxy-10(E), 12(Z)-octadecadienoic acid and 9(S), 10-epoxy-10, 12(Z)-octadecadienoic acid were isolated and characterized demonstrated the presence of 9-lipoxygenase and allene oxide synthase activities in the tissue preparation used. The allene oxide generated from linoleic acid by action of these enzymes was further converted into the cyclopentenone and α-ketol products by cyclization and hydrolysis, respectively. Incubation of [1-¹⁴C]linolenic acid with the preparation of potato stolons afforded 2-oxo-5-[2′(Z)-pentenyl]-3-cyclopentene-1-octanoic acid (trivial name, 10-oxo-11, 15(Z)-phytodienoic acid), i.e., an isomer of the jasmonate precursor 12-oxo-10, 15(Z)-phytodienoic acid. Quantitative determination of 10-oxo-11-phytoenoic acid in linoleic acid-supplied homogenates of different parts of the potato plant showed high levels in roots and stolons, lower levels in developing tubers, and no detectable levels in leaves.     

Oxygenated fatty acid constituents of soybean phosphatidylcholines

Bitter-tasting phosphatidylcholines from hexane-defatted soybean flakes were chromatographically separable from ordinary soy phosphatidylcholines (SPC). The bitter-tasting SPC contain 32% oxygenated fatty acids in addition to palmitic, stearic, oleic, linoleic, and linolenic acids. Identification of these oxygenated acids was based on infrared, ultraviolet, proton nuclear magnetic resonance, and mass spectral characteristics of methyl ester derivatives which were separated and purified by column and thin layer chromatography. The fatty acid methyl esters identified were (a) 15, 16-epoxy-9, 12-octadecadienoate, (b) 12, 13-epoxy-9-octadecenoate, both with double bonds and epoxide groups predominantly ofcis configuration; (c) 13-oxo-9,11-and 9-oxo-10, 12-octadecadienoates; (d) 13-hydroxy-9, 11- and 9-hydroxy-10, 12-octadecadienoates; (e) 9, 10, 13-trihydroxy-11- and 9,12,13-trihydroxy-10-octadecenoates. In addition, trace amounts of (f) 11-hydroxy-9,10-epoxy-12-and 11-hydroxy-12,13-epoxy-9-octadecenoates; (g) 13-oxo-9-hydroxy-10-and 9-oxo-13-hydroxy-11-octadecenoates; (h) 9,10-dihydroxy-12- and 12, 13-dihydroxy-9-octadecenoates; and (i) 9,12,13-dihydroxyethoxy-10- and 9,10,13-dihydroxyethoxy-11-octadecenoates were indicated by mass spectrometry. Dihydroxyethoxy compounds (i) were possibly formed upon extraction of the SPC from flakes by 80% ethanol. Except for the first two epoxy compounds, labelled a and b, the oxygenated fatty acids are similar to the products formed by homolytic decomposition of linoleic acid hydroperoxide. The first two compounds with predominantlycis configuration may occur by action of fatty acid hydroperoxides on an unsaturated fatty acid. Presented in part at the 13th World Congress of the International Society for Fat Research, Marseille, France, August 31–September 4, 1976.     

Synthesis of some new styryl oxazolophenoxazines

Reductive acetylation of 3-aminophenoxaz-2-one (II) gave 3-acetylamino-2-acetoxy-phenoxazine (IV). Thermolysis of (IV) gave 2-methyl-5H-oxazolo(4,5-b)phenoxazine (V). The styryl derivatives (VIII) were synthesised by condensation of (V) with aromatic aldehydes. Quaternisation of (V) was carried out giving (VII). Oxidation of (V) using SeO₂ gave 2-formyl-5H-oxazolo(4,5-b)phenoxazine (VI). Fragmentation patterns of certain of the products under electron impact are suggested.     

Absolute configuration of 12-Oxo-10,15(Z)-phytodienoic acid

12-Oxo-10,15(Z)-phytodienoic acid biosynthesized from 13(S)-hydroperoxy-9(Z),11(E),15(Z)-octadecatrienoic acid using a preparation of corn (Zea mays L) hydroperoxide dehydrase recently was found to be a mixture of enantiomers in a ratio of 82∶18 (Hamberg, M., and Hughes, M.A. (1988)Lipids 23, 469–475). In this work, 12-oxophytodienoic acid and (+)-7-iso-jasmonic acid were converted into a common derivative, methyl 3-hydroxy-2-pentyl-cyclopentane-1-octanoate. From gas liquid chromatographic analysis of the (−)-menthoxycarbonyl derivative of methyl 3-hydroxy-2-pentyl-cyclopentane-1-octanoates prepared from 12-oxophytodienoic acid and (+)-7-iso-jasmonic acid, it could be deduced that the major enantiomer of 12-oxophytodienoic acid had the 9(S),13(S) configuration. Therefore, in the major enantiomer of 12-oxophytodienoic acid, the configurations of the side chainbearing carbons are identical to the configurations of the corresponding carbons of (+)-7-iso-jasmonic acid, thus giving support to previous studies indicating that 12-oxophytodienoic acid serves as the precursor of (+)-7-iso-jasmonic acid in plant tissue. When absolute configurations of C-9 and C-13 are not specifically indicated, phytonoic acid is used to denote 2-pentyl-cyclopentane-1-octanoic acid in which the two side chains have thecis relationship, whereas phytonoic acid (trans isomer) denotes 2-pentyl-cyclopentane-1-octanoic acid in which the two side chains have thetrans relationship.