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1.
The title compounds were prepared by six different routes, and recommendations are given for the more convenient procedures in laboratory-scale syntheses. Modifications in the literature preparations of the 9E,11E and 9E,11Z isomers are described. Baseline separation of a prepared mixture of all four isomers of the (9Z, 11Z), (9E, 11E), (9E, 11Z), and (9Z, 11E)-9,11-hexadecadienals was achieved using GC methods with standard capillary columns. [13C]NMR spectroscopy of the alkene carbon atoms clearly differentiates between theZ,Z, E,E and eitherE,Z orZ,E isomers of the precursor dienols and thus of the dienals.  相似文献   

2.
Adult males ofSemiothisa signaria dispuncta (Walker) were attracted to field traps baited with (Z,Z,Z)-3,6,9-octadecatriene and (Z,Z)-6,9-cis-3,4-epoxy-octadecadiene. However, analyses of sex pheromone gland extracts of females of this species by GC-MS and by GC in combination with an electroantennograph detector (GC-EAD) showed the pheromone to be comprised of a mixture of the next lower homologs: (Z,Z,Z)-3,6,9-heptadecatriene and (Z,Z)-6,9-cis-3,4-epoxy-heptadecadiene. Blends of these two C17 compounds were subsequently found to be more attractive to males in the field than the corresponding C18 mixtures. Sex pheromones of two otherSemiothisa species were also found to contain C17 components. (Z,Z,Z)-3,6,9-Heptadecatriene, detected by GC-EAD analysis of a female abdominal tip extract ofS. bicolorata (Fabricius), attracted conspecific males, and this attraction was significantly reduced by additions of (Z,Z)-6,9-cis-3,4-epoxyheptadecadiene, the major pheromone component ofS. signaria dispuncta, to the lure. (Z,Z)-3,9-cis-6,7-Epoxy-heptadecadiene was detected by GC-EAD analysis as the primary male antennal stimulatory component present in abdominal tip extracts ofS. ulsterata (Pearsall), and males of this species were attracted to traps baited with this epoxide. Each of these three C17 compounds constitute previously unknown lepidopteran sex pheromone components. Blends of (Z,Z, Z)-3,6,9-heptadecatriene and (Z,Z)-3,9-cis-6,7-epoxyheptadecadiene attracted males of a fourth species,S. delectata Hulst, but no females of this species were obtained to permit analysis of its sex pheromone. The occurrence of (Z,Z,Z)-3,6,9-heptadecatriene inS. neptaria (Guenee) females was indicated by GC-MS analysis of an abdominal tip extract; however, no males were attracted to any of the fielded mixtures containing this hydrocarbon.  相似文献   

3.
Incubation of [1-14C]linoleic acid with an enzyme preparation obtained from the red algaLithothamnion corallioides Crouan resulted in the formation of 11-hydroxy-9(Z),12(Z)-octadecadienoic acid as well as smaller amounts of 9-hydroxy-10(E),12(Z)-octadecadienoic acid, 13-hydroxy-9(Z),11(E)-octadecadienoic acid and 11-keto-9(Z),12(Z)-octadecadienoic acid. Steric analysis showed that the 11-hydroxyoctadecadienoic acid had the (R) configuration. The 9- and 13-hydroxyoctadecadienoic acids were not optically pure, but were due to mixtures of 75% (R) and 25% (S) enantiomers (9-hydroxyoctadecadienoate), and 24% (R) and 76% (S) enantiomers (13-hydroxy-octadecadienoate). 11-Hydroxyoctadecadienoic acid was unstable at acidic pH. In acidified water, equal parts of 9(R,S)-hydroxy-10(E),12(Z)-octadecadienoate and 13(R,S)-hydroxy-9(Z),11(E)-octadecadienoate, plus smaller amounts of the corresponding (E),(E) isomers were produced. In aprotic solvents, acid treatment resulted in dehydration and in the formation of equal amounts of 8,10,12- and 9,11,13-octadecatrienoates. The enzymatic conversion of linoleic acid into the hydroxyoctadecadienoic acids and the ketooctadecadienoic acid was oxygen-dependent; however, inhibitor experiments indicated that neither lipoxygenase nor cytochrome P-450 were involved in the conversion. This conclusion was supported by experiments with18O2 and H2 18O, which demonstrated that the hydroxyl oxygen of the hydroxy-octadecadienoic acids and the keto oxygen of the 11-ketooctadecadienoic acid were derived from water and not from molecular oxygen. The term “oxylipin” was introduced recently (ref. 1) as an encompassing term for oxygenated compounds which are formed from fatty acids by reaction(s) involving at least one step of mono- or dixoygenase-catalyzed oxygenation.  相似文献   

4.
The peroxisome proliferator‐activated receptor (PPAR)α is mainly expressed in the liver and plays an important role in the regulation of lipid metabolism. It has been reported that PPARα activation enhances fatty acid oxidation and reduces fat storage. Therefore, PPARα agonists are used to treat dyslipidemia. In the present study, we found that 9‐oxo‐10(E),12(Z),15(Z)‐octadecatrienoic acid (9‐oxo‐OTA), which is a α‐linolenic acid (ALA) derivative, is present in tomato (Solanum lycopersicum) extract. We showed that 9‐oxo‐OTA activated PPARα and induced the mRNA expression of PPARα target genes in murine primary hepatocytes. These effects promoted fatty acid uptake and the secretion of β‐hydroxybutyrate, which is one of the endogenous ketone bodies. We also demonstrated that these effects of 9‐oxo‐OTA were not observed in PPARα‐knockout (KO) primary hepatocytes. To our knowledge, this is the first study to report that 9‐oxo‐OTA promotes fatty acid metabolism via PPARα activation and discuss its potential as a valuable food‐derived compound for use in the management of dyslipidemia.  相似文献   

5.
Transannular Reactions of Cycloalkenes, Cycloalkadienes and Cycloalkatrienes. VIII. The Electrophilic Addition of Pseudohalogenes to Cycloocta-1(Z), 5(Z)-diene The reaction of cycloocta-1(Z), 5(Z)-diene 5 with chlorothiocyanate is described. The main process is the normal anti-addition to produce trans-5-chloro-6-thiocyanato-(Z)-cyclooctene 6 . In addition 2,6-dichloro-9-thiabicyclo [3.3.1] nonane 7 and 2,6-dithiocyanato-9-thiabicyclo[3.3.1] nonane 8 are obtained as products of a transannular reaction.  相似文献   

6.
Peroxisome proliferator‐activated receptor (PPAR)γ is expressed in adipose tissue and plays a key role in the regulation of adipogenesis. PPARγ activators are known to have potent antihyperglycemic activity and are used to treat insulin resistance associated with diabetes. Therefore, many natural and synthetic agonists of PPARγ are used in the treatment of glucose disorders. In the present study, we found that 13‐oxo‐9(Z),11(E),15(Z)‐octadecatrienoic acid (13‐oxo‐OTA), a linolenic acid derivative, is present in the extract of tomato (Solanum lycopersicum), Mandarin orange (Citrus reticulata), and bitter gourd (Momordica charantia). We also found that 13‐oxo‐OTA activated PPARγ and induced the mRNA expression of PPARγ target genes in adipocytes, thereby promoting differentiation. Furthermore, 13‐oxo‐OTA induced secretion of adiponectin and stimulated glucose uptake in adipocytes. To our knowledge, this is the first study to report that 13‐oxo‐OTA induces adipogenesis through PPARγ activation and to present 13‐oxo‐OTA as a valuable food‐derived compound that may be applied in the management of glucose metabolism disorders.  相似文献   

7.
Each of 10 (Z,Z)-9,19 hydrocarbon dienes (28–37 carbons) found in female yellowheaded spruce sawflies,Pikonema alaskensis (Rohwer), was synthesized and found to be attractive to males by field bioassay. These dienes oxidize slowly in air, major products being aldehydes. One product common to all the dienes, (Z)-10-nonadecenal (Z10–19∶Al), and one from the 29-carbon diene only, (Z)-10-eicosenal, initiated flight and caused upwind anemotaxis in males in a greenhouse bioassay.Z10–19∶Al was incorporated into Hercon® controlled release formulations and was active in the field. The aldehyde could be useful for monitoring sawfly populations.  相似文献   

8.
α-Tocopherol was reacted with methyl 13(S)-hydroperoxy-9(Z),11(E)-octadecadienoate in the presence of an iron-chelate, Fe(III)-acetylacetonate, at 37°C in benzene. The reaction was carried out either aerobically or anaerobically. The main products of α-tocopherol under air were isolated and identified as two stereoisomers of 4a,5-epoxy-8a-hydroperoxy-α-tocopherone, four stereoisomers of methyl 9-(8a-dioxy-α-tocopherone)-12,13-epoxy-10(E)-octadecenoate, four stereoisomers of methyl 11-(8a-dioxy-α-tocopherone)-12,13-epoxy-9(Z)-octadecenoate, two stereoisomers of methyl 13(S)-(8a-dioxy-α-tocopherone)-9(Z),11(E)-octadecadinoate, and α-tocopherol dimer. Besides the 8a-(lipid-peroxy)-α-tocopherones, two stereoisomers of methyl 11-(α-tocopheroxy)-12(S),13(S)-epoxy-9(E)-octadecenoate, two stereoisomers of methyl 9-(α-tocopheroxy)-12(S),13(S)-epoxy-10(E)-octadecenoate, and two isomers of methyl (α-tocopheroxy)-octadecadienoate were obtained under nitrogen atmosphere. The results indicate that the peroxyl radicals from lipid hydroperoxides prefer to react with the 8a-carbon radical of α-tocopherol and the carbon-centered radicals react with the phenoxyl radical of α-tocopherol.  相似文献   

9.
10.
Transformation of 13(S)-hydroperoxy-9(Z),11(E)-octadecadienoic acid (13S-HPOD) to 13(S)-hydroxy-9(Z),11(E)-octadecadienoic acid (13S-HOD) under alkaline conditions (0.05 to 5 M KOH) occurred first-order with respect to 13S-HPOD concentration. Overall yield was about 80%. The energy of activation at higher concentrations (3.75 to 5 M KOH) was determined to be in the range of 15.3 to 15.6 kcal. Compared to the 13S-HPOD conversion, 13(S)-hydroperoxy-9(Z),11(E),15(Z)-octadecatrienoic acid (13S-HPOT) was converted at a faster rate to the corresponding hydroxy fatty acid (13S-HOT), with the reaction also being first-order. Chiral phase high-performance liquid chromatography demonstrated that in the transformation the stereochemistry of both the 13S-HPOD and 13S-HPOT reactants was preserved. Manometric analyses of the KOH/13S-HPOD reaction showed an uptake of gas, which amounted to 11% of the mols of reactant 13S-HPOD on the assumption that the gas was O2. As there is a theoretical loss of 1 oxygen atom in the reaction, the fate of this oxygen (possiblyvia active oxygen species) may involve reaction with 13S-HPOD/13SHOD to form the 20% by-products.  相似文献   

11.
12.
A new and simple differential pulse polarographic method for the analysis of wine has been established. With this method, it was possible to determine simultaneously six trace elements in wine. There was no need for time consuming extraction and separation procedures with danger of contamination. The polarogram of wet digested wine was taken initially in pH 2 acetate buffer and Pb, Cd, and Zn were determined by standard additions. Ethylene diamine tetraacetic acid (EDTA) was added and pH was increased to six by addition of NaOH. Fe and Cu were determined subsequently. The ammonia buffer, pH 9.5, was identified as the best medium for separation and determination of Ni and Zn. The quantities of trace elements were found as Cu 290 ± 20 μg L−1, Fe 8960 ± 50 μg L−1, Pb 148 ± 17 μg L−1, Cd 16 ± 8 μg L−1, Zn 460 ± 25 μg L−1, and Ni 78 ± 17 μg L−1.  相似文献   

13.
Recently, corn (Zea mays L.) hydroperoxide dehydrase was found to catalyze the conversion of 13(S)-hydroperoxy-9(Z),11(E)-octadecadienoic acid into an unstable fatty acid allene oxide, 12,13(S)-epoxy-9(Z),11-octadecadienoic acid. This study is concerned with the chemistry of 12,13(S)-epoxy-9(Z),11-octadecadienoic acid in the presence of vertebrate serum albumins. Albumins were found to greatly enhance the aqueous half-life of the allene oxide, i.e. 14.1±1.8 min, 11.6±1.2 min and 4.8±0.5 min at 0 C in the presence of 15 mg/ml of bovine, human and equine serum albumins, respectively, as compared with ca. 33 sec in the absence of albumin. Degradation of allene oxide in the presence of bovine serum albumin led to the formation of a novel cyclization product, i.e. 3-oxo-2-pentyl-cyclopent-4-en-1-octanoic acid (12-oxo-10-phytoenoic acid, in which the relative configuration of the side chains attached to the five-membered ring istrans). Steric analysis of the cyclic derivative showed that the compound was largely racemic (ratio between enantiomers, 58∶42). 12-Oxo-10,15(Z)-phytodienoic acid, needed for reference purposes, was prepared by incubation of 13(S)-hydroperoxy-9(Z),11(E),15(Z)-octadecatrienoic acid with corn hydroperoxide dehydrase. Steric analysis showed that the 12-oxo-10,15(Z)-phytodienoic acid thus obtained was not optically pure but a mixture of enantiomers in a ratio of 82∶18. The first paper in this series is Reference 1.  相似文献   

14.
汇雯 《清洗世界》2003,(1):35-37
Additines食用添加剂   食物和饮品内加入食用添加剂的目的在于增加食品的味道、香气和质感,添加剂可分为天然和人造两种.不少人对添加剂或人造色素有过敏反应,只是程度因人而异.平时要多留意吃过的饮品、乳酪、糖果、干果的颜色是否过于鲜艳,或吃过加工肉食后的反应,一些明显的不良反应如晕眩、面红耳赤、头痛或肠胃不舒服等.   ……  相似文献   

15.
Sex attractants for the geometrid mothsEufidonia convergaria andCaripeta angustiorata, and the noctuid mothRivula propinqualis have been elucidated during field screening of a series of (3Z,6Z,9Z)-triene hydrocarbons (C17–22), and the racemic and enantiomerically enriched monoepoxydienes derived from those hydrocarbons. Biologically active compounds were identified by a combination of field testing of synthetic standards, electroantennography, and coupled gas chromatography-electroantennogram detection.E. convergaria males were optimally attracted by a 11 blend of (3Z,9Z)-(6S,7R)-epoxy-nonadecadiene (3Z,9Z-6S,7R-epoxy-19H); other abbreviations follow the same system) with (3Z,6Z,9Z)-nonadecatriene (3Z,6Z,9Z-19H). The 6R,7S enantiomer of the epoxide had no apparent biological activity, either as an attractant or as a behavioral antagonist. Male moths also were attracted to blends of the C18 and C20 homologs of the triene and the epoxide. 3Z,6Z,9Z-19H and 3Z,6Z-cis-6,7-epoxy-19H were identified inE. convergaria female pheromone gland extracts. Males of the geometrid moth speciesC. angustiorata were attracted by a 11 blend of 3Z,6Z,9Z-19H and enantiomerically enriched 3Z,9Z-6R,7S-epoxy-19H. Males of the noctuid mothR. propinqualis were attracted by an approximately 101 blend of 3Z,6Z,9Z-19H and enantiomerically enriched 3Z,9Z-6S, 7R-epoxy-19H. The components were synergistic, with neither being attractive alone. The blend ratio was quite specific, as the attractiveness of blends decreased sharply on either side of the optimum ratio.Issued as NRC No. 30266.  相似文献   

16.
叙述了Fe3 、Zn2 、Mn2 、Cu2 、Ca2 、Mg2 等离子共存体系中采用六次甲基四胺 -铜试剂沉淀除去Fe3 、Zn2 、Mn2 、Cu2 等干扰离子 ,用EDTA滴定钙镁的方法 ,该方法钙的回收率在 99.7%~ 10 0 .3 % ;镁的回收率在 10 0 .0 %~ 10 0 .4% ,标准偏差为 0 .0 2 2。  相似文献   

17.
The sex pheromone of the red banded mango caterpillar, Deanolis sublimbalis (Lepidoptera: Crambidae), a serious pest of the mango Mangifera indica (Anacardiaceae) in India and Southeast Asia and a recent invader into northern Australia, has been identified. Three candidate compounds were identified from pheromone gland extracts of female moths, using gas chromatography (GC), GC-electroantennographic detection and GC-mass spectrometric analyses, in conjunction with dimethyldisulfide derivatization. Field bioassays established that both (Z)-11-hexadecenal (Z11-16:Ald) and (3Z,6Z,9Z)-tricosatriene (3Z,6Z,9Z-23:Hy) were required for attraction of male D. sublimbalis moths, and 1,000 μg of a 1:1 mix of Z11-16:Ald and 3Z,6Z,9Z-23:Hy was more attractive to male moths than caged virgin females. However, the binary blend was only attractive when the isomeric purity of the monounsaturated aldehyde was >99%, suggesting that the (E)-isomer was inhibitory. Although (Z)-11-hexadecen-1-ol (Z11-16:OH) was tentatively identified in gland extracts, the addition of this compound to the binary blend did not increase the numbers of moths captured. The pheromone can now be used in integrated pest management strategies. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   

18.
The alkaloidal venom components of two species of thief ants,Solenopsis (Diplorhoptrum) species AA andS. (Diplorhoptrum)conjurata have been found to contain (5Z,9Z)-3-hexyl-5-methylindolizidine and a mixture of (5Z,9Z)-3-ethyl-5-methylindolizidine andcis-2-methyl-6-nonyl-piperidine,trans-2-methyl-6-nonylpiperidine,cis-2-methyl-6-undecylpiperidine, and hexadecanoic acid.Monomorium pharaonis was similarly investigated and found to contain the indolizidine and pyrrolidines previously described (Ritter et al., 1977b). Both indolizidines were synthesized along with their stereoisomers and separated by preparative gas chromatography. Spectral studies revealed the stereochemistry to be 5Z,9Z in both cases. The stereochemistry of 2-butyl-5-pentylpyrrolidine inM. phaeronis has also been established. Biosynthetic relationships are discussed.  相似文献   

19.
Eleven diamide extractants having the different backbones were synthesized and their extractability for lanthanides(III) and actinides(III), (IV), (V) and (VI) were measured and compared. The diamides investigated include (CH2) n ─(CONR1,R2)2, (n = 0, 1, 2, 3), O─((CH2) n─CONR1,R2)2, S─((CH2) n─CONR1,R2)2, and SS─((CH2)n′″─CONR1,R2)2, (n′, n″, n′″ = 1, 2). The diglycolamide introducing an ether oxygen into the main frame, O─(CH2─CONR1,R2)2, exhibited the highest extractability for An(III), (IV) and (VI), as compared with the other bidentate diamides. It is clear from the present results that the thiadiglycolamide, TDGA, which substitutes ether sulfur atom for oxygen in DGA molecule, also enhances the extraction of actinides. The lanthanide pattern, the distribution ratios versus the atomic number, by diglycolamide in HNO3-n-dodecane system exhibited a gradual increase of distribution ratio with increase in the atomic number, the opposite trend to that obtained by the other diamides.  相似文献   

20.
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.  相似文献   

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