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1.
[2–14C]-(2Z,4E)-γ-Ionylideneethanol and [2–14C]-(2Z,4E)-γ-ionylideneacetic acid were converted by Cercospora cruenta to [2–14C]-(2Z,4E)-1′,4′-dihydroxy-γ-ionylideneacetic acid and [2-14C]-(2Z,4E)-4′-hydroxy-γ-ionylideneacetic acid, which are intermediates of ABA biosynthesis in C. cruenta.  相似文献   

2.
The long-chain aldehydes, (8Z,11Z,14Z)-8,11,14-heptadecatrienal, (7Z,10Z,13Z)-7,10,13-hexadecatrienal, and (8Z,11Z)-8,11-heptadecadienal, were concisely synthesized by using Grignard coupling, catalytic hydrogenation with the Lindlar catalyst, and oxidation with Dess–Martin periodinane as the key steps. Particularly, (8Z,11Z,14Z)-8,11,14-heptadecatrienal and (7Z,10Z,13Z)-7,10,13-hexadecatrienal both possessed a seaweed-like odor.  相似文献   

3.
Lycopene has a large number of geometric isomers caused by E/Z isomerization at arbitrary sites within the 11 conjugated double bonds, offering varying characteristics related to features such as antioxidant capacity and bioavailability. However, the geometric structures of only a few lycopene Z-isomers have been thoroughly identified from natural sources. In this study, seven multi-Z-isomers of lycopene, (9Z,13′Z)-, (5Z,13Z,9′Z)-, (9Z,9′Z)-, (5Z,13′Z)-, (5Z,9′Z)-, (5Z,9Z,5′Z)-, and (5Z,9Z)-lycopene, were obtained from tomato samples by thermal isomerization, and then isolated by elaborate chromatography, and fully assigned using proton nuclear magnetic resonance. Moreover, the theoretically preferred pathway from (all-E)-lycopene to di-Z-isomers was examined with a computational approach using a Gaussian program. Fine-tuning of the HPLC separation conditions led to the discovery of novel multi-Z-isomers, and whose formation was supported by advanced theoretical calculations.  相似文献   

4.
Among terrestrial orchids, and particularly among the subtribe Orchidinae, flies are underrepresented as pollinators. The European Neotinea ustulata, which developed specialized pollination by tachinid flies, is known to produce high relative concentrations of the floral cuticular alkenes (Z)-11-tricosene and (Z)-11-pentacosene (referred to as (Z)-11-C23/C25enes), which seem to be uncommon among orchid flowers. If the evolution of tachinid pollination is related to that of (Z)-11-C23/C25enes, we can expect that closely related species have a different floral chemical pattern and significantly small or no production of (Z)-11-C23/C25enes, independently of their pollinator guild identity (e.g., bees, flies, moths). We chemically compared the floral cuticular composition among Neotinea species, performed electrophysiological analyses, reconstructed the phylogenetic Orchidinae tree, and identified the evolutionary history of pollinator guild and (Z)-11-C23/C25enes production within the Orchidinae. Neotinea ustulata has evolved a markedly different floral cuticular composition compared to other Neotinea and produces both compounds ((Z)-11-C23/C25enes) in high relative quantities (i.e., above 8% in combination), which are detectable by tachinid antennae. Moreover, most Orchidinae taxa have minimal or no production of these alkenes, independently of the identity of their pollinator guild. Our ancestral reconstruction suggested that (Z)-11-C23/C25enes production was an evolutionary exaptation in Neotinea, whereas tachinid pollination was a unique evolutionary innovation for N. ustulata. Floral cuticular composition and, in particular, the combined production of (Z)-11-C23/C25enes at relatively high concentrations is intimately linked to the evolution of tachinid pollination within the Orchidinae.  相似文献   

5.
(Z)-3-Hexene-1, 6-diol, a new synthon for the synthesis of (Z)-olefinic pheromones, was prepared from 1, 4-cyclohexadiene. This synthon was used in the synthesis of (Z, Z)-3, 13-octadecadienyl acetate, whose high stereochemical purity at C–3 was essential in attracting male Synanthedon tenuis Butler.  相似文献   

6.
All-E-(3R,3′R,6′R)-lutein, all-E-(3R,3′R)-zeaxanthin, all-E-(3R,3′S,6′R)-3′-epilutein and some geometrical isomers of the former two dihydroxycarotenoids have been separated from an extract of human plasma by semipreparative high-performance liquid chromatography on a silica-based nitrile-bonded column. In the order of chromatographic elution, the isolated fractions were identified as all-E-lutein, all-E-zeaxanthin, all-E-3′-epilutein, 9Z-lutein, 9′Z-lutein, a mixture of 13Z-lutein and 13′Z-lutein, 9Z-zeaxanthin, 13Z-zeaxanthin and 15Z-zeaxanthin. The structures of all compounds, including the relative configuration at C(3′) and C(6′) of the luteins and the position of the stereomutated double bonds in the geometrical isomers, were unambiguously established by 1H nuclear magnetic resonance spectroscopy. The absolute configuration of the three all-E compounds was derived by circular dichroism and is also assumed to be valid for the geometrical isomers. The ultraviolet—visible absorption and mass spectra of each of the individually isolated compounds were also in agreement with the proposed structures.  相似文献   

7.
The plum cankerworm moth, Cystidia couaggaria couaggaria (Geometridae: Ennominae), is a defoliator of Chinese plum trees (Prunus mume). The pheromone components of the female were analyzed by gas chromatography (GC) with an electro-antennographic (EAG) detector and GC coupled with mass spectrometry. The crude pheromone extract included several EAG-active components, i.e., trienyl, dienyl, and saturated hydrocarbons, with a C21–C25 straight chain. The characteristic mass spectra indicated the unsaturated hydrocarbons to be (3Z,6Z,9Z)-3,6,9-trienes and (6Z,9Z)-6,9-dienes. In the fields, mixtures of the synthetic C21 and C23 trienes in a ratio of 2:3 and 1:4 successfully attracted males of this diurnal species during daytime. While the male antennae responded to the C25 triene and saturated hydrocarbons, their synergistic effects were not observed on the male attraction in the fields. Addition of the C21 diene interestingly inhibited the activity of the triene mixture. Males of Cystidia truncangulata, a sympatric diurnal congener of C. c. couaggaria, showed similar EAG responses to the unsaturated hydrocarbons, but no C. truncangulata males were attracted by the lures tested for C. c. couaggaria males, indicating that the identified hydrocarbons comprised the species-specific pheromone of C. c. couaggaria females.  相似文献   

8.
A new irieane-type diterpene, 12-hydroxypinnaterpene C ( 1 ), and 21 known compounds, angasiol acetate ( 2 ), angasiol ( 3 ), 11-deacetylpinnaterpene C ( 4 ), palisadin A ( 5 ), 12-acetoxypalisadin B ( 6 ), 12-hydroxypalisadin B ( 7 ), aplysistatin ( 8 ), luzodiol ( 9 ), 5-acetoxy-2-bromo-3-chloro-chamigra-7(14),9-dien-8-one ( 10 ), neoirietriol ( 11 ), neoirietetraol ( 12 ), (3Z)-laurenyne ( 13 ), cupalaurenol ( 14 ), cupalaurenol acetate ( 15 ), (3Z)-venustinene ( 16 ), 10-hydroxykahukuene B ( 17 ), aplysiol B ( 18 ), (3Z)-13-epipinnatifidenyne ( 19 ), 3Z,6R,7R,12S,13S-obtusenyne ( 20 ), (3Z,9Z)-7-chloro-6-hydroxy-12-oxo-pentadeca-3,9-dien-1-yne ( 21 ), and cholest-7-en-3,5,7-triol ( 22 ) were isolated from the digestive diverticula of Aplysia argus from the Ikei Island in Okinawa, Japan. The structures of these compounds were determined using spectroscopic methods such as NMR and HR-ESI-MS. These compounds were tested for their antibacterial activity against the phytopathogen Ralstonia solanacearum. Compounds 11 and 21 exhibited antibacterial activity at 30 μg/disc. In this study, we also discuss the types of red algae that A. argus feeds on in the shallow waters of Okinawa Prefecture.  相似文献   

9.
Amides in a CH2Cl2 extract from the fruits of Piper retrofractum were detected by HPLC/APCI-MS. Seven new unsaturated amides, together with six known ones, were isolated, and their structures were determined to be N-isobutyl-2E,4E,12Z-octadecatrienamide (1), N-isobutyl-2E,4E,14Z-eicosatrienamide (2), 1-(octadeca-2E,4E,12Z-trienoyl)piperidine (3), 1-(eicosa-2E,4E,14Z-trienoyl)piperidine (4), 1-(octadeca-2E,4E-dienoyl)piperidine (5), 1-(eicosa-2E,4E-dienoyl)piperidine (6), and 1-(eicosa-2E,14Z-dienoyl)piperidine (7) on the basis of chemical and spectroscopic evidence.  相似文献   

10.
Several compounds having the basic α-ionylideneacetic acid structure were tested in Cercospora rosicola resuspensions. At 100 μm, all the compounds inhibited abscisic acid (ABA) biosynthesis. Time studies with unlabelled and deuterated (2Z,4E)- and (2E,4E)-α-ionylideneacetic acids showed rapid conversions into both (2Z,4E)- and (2E,4E)-4′-keto-α-ionylideneacetic acids as major products. Incorporation of the label into ABA was specific for the 2Z,4E-isomer. Minor products, identified by GC-MS, were (2Z,4E)- and (2E,4E)-4′-hydroxy-α-ionylideneacetic acids and (2Z,4E)-1′-hydroxy-α-ionylideneacetic acid. The conversion to (2Z,4E)-l′-hydroxy-α-ionylideneacetic acid has not been previously reported and was specific for the 2Z,4E-isomer. A time study for the conversion of methyl esters of [2H3]-(2Z,4E)- and [2H3]-(2E,4E)-4′-keto-α-ionylideneacetates showed a slow introduction of the l′-hydroxyl group and specificity for 2Z,4E-isomer. Conversion of the ethyl esters of (2Z,4E)- and (2E,4E)-l′-hydroxy-α-ionylideneacetates into the ethyl esters of both ABA and (2E,4E)-ABA demonstrated that ABA can be formed by oxidation of the 4′-position after the insertion of the 1′-hydroxy group. The ethyl 1′-hydroxy acids were also isomerized to the corresponding ethyl (2Z,4E)- and ethyl (2E,4E)-3′-hydroxy-β-ionylideneacetates. Ethyl (2Z,4E)-1′-hydroxy acid also gave small amounts of ethyl l′,4′-trans-diol of ABA. These results suggest that ABA may be formed through a (2Z,4E)-1′-hydroxy-α-ionylidene-type intermediate in addition to the previously proposed route through (2Z,4E)-4′-keto-α-ionylideneacetic acid.  相似文献   

11.
Single sensillum recordings from Cydia pomonella male antennae showed three different types of receptor neurons. The most abundant type was most sensitive to the main pheromone compound (E,E)-8,10-dodecadienol, while its response to the geometric isomers E,Z, Z,E and Z,Z was comparable to a tenfold lower dose of (E,E)-8,10-dodecadienol. This neuron type also responded to the four behaviorally antagonistic isomers of (Δ,Δ)-8,10-dodecadienyl acetate, among which it was most sensitive to the E,E isomer. Cross-adaptation studies showed that these compounds were all detected by the same receptor neuron type. Receptor neurons specifically tuned to (E,Z) or (Z,Z)-8,10-dodecadienol were not found, although these two compounds are behaviorally active. A second type of receptor neuron responded to all isomers of (Δ,Δ)-8,10-dodecadienyl acetate and was most sensitive to the E,E isomer. This neuron type did not respond to any of the isomers of (Δ,Δ)-8,10-dodecadienol. A third receptor neuron type was highly sensitive to the plant compound α-farnesene. The finding that the receptor neuron type tuned to the main pheromone compound responded even to strong behavioral antagonists aids the interpretation of ongoing behavioral studies for the development of the mating disruption technique in codling moth. Accepted: 3 March 2000  相似文献   

12.
Ovipositor washings from virgin female Cryptophlebia batrachopa (Meyrick) (Lepidoptera: Tortricidae) were analysed by gas chromatography (GC) linked to electroantennography (EAG) and by high-resolution GC. The major EAG-active component in ovipositor washings was shown to be (Z)-8-dodecenyl acetate with less than 0.5% of the E isomer. GC analysis of ovipositor washings from C. leucotreta confirmed the presence of approximately equal amounts of (Z)- and (E)-8-dodecenyl acetates (Persoons et al., 1977). When pure (Z)-8-dodecenyl acetate and mixtures containing up to 50% of the E isomer were tested in the field in Malawi where both Cryptophlebia species occurred, C. batrachopa male moths were caught only in traps baited with 10% or less of the E isomer and highest catches were recorded for the pure Z isomer. By contrast C. leucotretra males were caught predominantly by traps baited with more than 10% E isomer and no catches were recorded for the pure Z isomer. (Z)-8-dodecenyl acetate containing 1% of the E isomer was found to attract male moths of Opogona spp.
Résumé Les produits recueillis par lavages de l'ovipositeur de Cryptophlebia batrachopa Meyr. (Lep. Tortricidae) ont été analysés par chromatographie gazeuse (GC) associée à l'électroantennographie (EAG) et la GC à haute résolution. Le principal constituant actif en EAG provenant des lavages s'est révélé être le (Z)-8-dodécényl acétate avec moins de 0,5% de l'isomère E. L'analyse GC de ces produits de lavage de C. leucotreta ont confirmé la présence d'à peu près les mêmes quantités de (Z) et (E)-8-dodécényl acétates (Persoons et al., 1977). Quand des essais sur le terrain ont été effectués au Malawi, où existent les deux espèces de Cryptophlebia, avec du (Z)-8-dodécényl acétate et des mélanges comprenant jusqu'à 50% de l'isomère E, des mâles de C. batrachopa ont seuls été capturés dans des pièges contenant 10% ou moins de l'isomère E; les captures les plus élevées ont été obtenues avec l'isomère Z pur. A l'opposé, surtout des mâles de C. leucotreta ont été capturés dans des pièges garnis avec plus de 10% d'isomère E, et aucune capture n'a été obtenue avec l'isomère Z pur. Des mâles d'Opogona spp. ont été attirés par du (Z)-8-dodécényl acétate contenant 1% de l'isomère E.
  相似文献   

13.
Nineteen carotenoids were identified in extracts of petals of orange- and yellow-flowered cultivars of calendula (Calendula officinalis L.). Ten carotenoids were unique to orange-flowered cultivars. The UV–vis absorption maxima of these ten carotenoids were at longer wavelengths than that of flavoxanthin, the main carotenoid of calendula petals, and it is clear that these carotenoids are responsible for the orange color of the petals. Six carotenoids had a cis structure at C-5 (C-5′), and it is conceivable that these (5Z)-carotenoids are enzymatically isomerized at C-5 in a pathway that diverges from the main carotenoid biosynthesis pathway. Among them, (5Z,9Z)-lycopene (1), (5Z,9Z,5′Z,9′Z)-lycopene (3), (5′Z)-γ-carotene (4), and (5′Z,9′Z)-rubixanthin (5) has never before been identified. Additionally, (5Z,9Z,5′Z)-lycopene (2) has been reported only as a synthesized compound.  相似文献   

14.
We examined the biosynthetic pathway of abscisic acid (ABA) after isopentenyl diphosphate in a fungus, Cercospora cruenta. All oxygen atoms at C-1, -1, -1′, and -4′ of ABA produced by this fungus were labeled with 18O from 18O2. The fungus did not produce the 9Z-carotenoid possessing γ-ring that is likely a precursor for the carotenoid pathway, but produced new sesquiterpenoids, 2E,4E-γ-ionylideneethane and 2Z,4E-γ-ionylideneethane, along with 2E,4E,6E-allofarnesene. The fungus converted these sesquiterpenoids labeled with 13C to ABA, and the incorporation ratio of 2Z,4E-γ-ionylideneethane was higher than that of 2E,4E-γ-ionylideneethane. From these results, we concluded that C. cruenta biosynthesized ABA by the direct pathway via oxidation of ionylideneethane with molecular oxygen following cyclization of allofarnesene. This direct pathway via ionylideneethane in the fungus is consistent with that in Botrytis cinerea, except for the positions of double bonds in the rings of biosynthetic intermediates, suggesting that the pathway is common among ABA-producing fungi.  相似文献   

15.
(±)-(2Z,4E)-α-Ionylideneacetic acid (2) was enantioselectively oxidized to (?)-(l′S)-(2Z,4E)-4′-hydroxy-α-ionylideneacetic acid (3), (+)-(1′R)-(2Z,4E)-4′-oxo-α-ionylideneacetic acid (4) and (+)-abscisic acid (ABA) (1) by Cercospora cruenta IFO 6164, which can produce (+)-ABA and (+)-4′-oxo-α-acid 4. This metabolism was confirmed by the incorporation of radioactivity from (±)-(2-14C)-(2Z,4E)-α-acid 2 into three metabolites. (?)-4′-Hydroxy-α-acid 3 was a diastereoisomeric mixture consisting of major 1′,4′-trance-4′-hydroxy-α-acid 3a and minor 1′,4′-cis-4′-hydroxy-α-acid 3b. These structures, 3a and 3b, were confirmed by 13C-NMR and 1H-NMR analysis. Also, the enantioselectivity of the microbial oxidation was reexamined by using optically pure α-acid (+)-2 and (?)-2, as the substrates.  相似文献   

16.
Bioassay-guided fractionation of a methanol extract of the brown alga, Ishige sinicola, led to the isolation of five algicidal compounds. Their structures were determined to be α-monoglycerides of eicosa-5Z,8Z,11Z,14Z-tetraenoic (arachidonic) acid, octadeca-6Z,9Z,12Z,15Z-tetraenoic acid, linoleic acid and oleic acid, and 1-O-palmitoyl-3-O-(6-sulfo-α-D-quinovopyranosyl)-sn-glycerol on the basis of spectroscopic data and a comparison with the data in the literature. These glycerolipids showed moderate-to-high cell lysis activity against the red tide microalgal species, Heterosigma akashiwo, Karenia mikimotoi and Alexandrium catenella, at a concentration of 20 μg/mL.  相似文献   

17.
The four possible isomers of tetradeca‐4,8‐dien‐1‐yl acetate and corresponding alcohols were synthesized stereoselectively by synthetic routes employing Wittig coupling reaction for the preparation of (Z,E)‐ and (Z,Z)‐isomers, and alkylation of terminal alkynes for the preparation of (E,E)‐ and (E,Z)‐isomers as the key steps. Synthetic products were characterized by 13C‐ and 1H‐NMR spectroscopy as well as mass‐spectrometric methods. All four isomers gave distinctive mass spectra where m/z 81 fragments clearly dominated. Elution order, followed by retention index presented in parenthesis, of tetradeca‐4,8‐dien‐1‐ols was determined as (Z,Z) (2082.1), (Z,E) (2082.8), (E,E) (2083.1), and (E,Z) (2083.2) from unpolar SPB‐1 column, and as (E,E) (2210.2), (Z,E) (2222.1), (E,Z) (2223.4), and (Z,Z) (2224.7) from polar DB‐WAX column. The isomers of tetradeca‐4,8‐dien‐1‐yl acetates eluted in the order of (Z,Z) (2176.1), (Z,E) (2178.4), (E,Z) (2185.9), and (E,E) (2186.4) from SPB‐1, and (Z,E) (2124.3), (E,E) (2157.7), (Z,Z) (2128.9), and (E,Z) (2135.9) from DB‐WAX columns. Field‐screening tests for attractiveness of tetradeca‐4,8‐dien‐1‐yl acetates revealed that (4Z,8E)‐tetradeca‐4,8‐dien‐1‐yl acetate significantly attracted Phyllonorycter coryli and Chrysoesthia drurella males. (4E,8E)‐Tetradeca‐4,8‐dien‐1‐yl acetate was the most efficient attractant for Ph. esperella and Ph. saportella males, and (4E,8Z)‐tetradeca‐4,8‐dien‐1‐yl acetate was attractive to Ph. cerasicolella males.  相似文献   

18.
The methanol extract of Ehretia dicksonii provided (10E,12Z,15Z)-9-hydroxy-10,12,15-octadecatrienoic acid methyl ester (1) which was isolated as an anti-inflammatory compound. Compound 1 suppressed 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced inflammation on mouse ears at a dose of 500 μg (the inhibitory effect (IE) was 43%). Linolenic acid methyl ester did not inhibit this inflammation at the same dose. However, the related compounds of 1, (9Z,11E)-13-hydroxy-9,11-octadecadienoic acid (5) and (9Z,11E)- 13-oxo-9,11-octadecadienoic acid (6), showed potent activity (IE500 μg of 63% and 79%, respectively). Compounds 1, 4 ((9Z,12Z,14E)-16-hydroxy-9,12,14-octadecatrienoic acid), 5 and 6 also showed inhibitory activity toward soybean lipoxygenase at a concentration of 10 μg/ml.  相似文献   

19.
From the fresh roots of Heliopsis longipes three new minor alkamides: longipinamide A (N-isobutyl-8,10-diynoic-3Z-undecenamide), longipenamide A (N-isobutyl-syn-8,9-dihydroxy-2E,6Z-decadienamide) and longipenamide B (N-isobutyl-syn-6,9-dihydroxy-2E,7E-decadienamide); three known alkamides: affinin (spilanthol, N-isobutyl-2E,6Z,8E-decatrienamide), N-isobutyl-2E,6Z-decadienamide and N-isobutyl-2E-decenamide; and 11 other known compounds were isolated. The structures of the three new minor alkamides were established by 1D and 2D NMR spectroscopy including 1H, 13C, DEPT, COSY, HSQC, and HMBC experiments, as well as by EI and FAB+ mass spectrometry. To our knowledge, this is the first report of the isolation of linear dihydroxyalkamides as natural products.  相似文献   

20.
Phytochemical investigation of the radix of Angelica sinensis has led to the isolation and identification of a new phthalide dimer, (3Z)-(3aR,6S,3′R,8′S)-3a.8′,6.3′-diligustilide (1), along with three known phthalide dimers, including riligustilide (2), levistolide A (3), senkyunolide O (4), and three known phthalide monomers, including 3,9-dihydroxyl-ligustilide (5), (Z)-butylidene phthalide (6), (Z)-ligustilide (7). Their structures were determined by spectroscopic methods including IR, NMR (1H NMR, 13C NMR, COSY, HSQC, HMBC and NOESY) and MS. Meanwhile, the possible biosynthesis pathways of compounds 1 and 5 were hypothesized.  相似文献   

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