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1.
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   

2.
To elucidate the role of the methyl substituent on the side chain of abscisic acid (ABA), we synthesized (2Z,4E)-3-demethyl-α-ionylideneacetic acid (4) and its related analogs, methyl (2Z)-3-demethyl-β-ionylideneacetate 1′,2′-epoxide (9) and methyl (2Z) and (2E)-3-demethyl-abscisate (12) and (13). The biological assay of these compounds suggested that the 3-methyl group on the side chain of ABA was indispensable to biological activity.  相似文献   

3.
The ethyl acetate (EtOAc) soluble fraction of the 85% ethanol (EtOH) extract of the dried bark of Limonia acidissima potently inhibited nitric oxide (NO) production in lipopolysaccharide (LPS) activated BV-2 cells, a microglial cell line. Bioassay-guided column chromatography separation afforded a new stereoisomer of neolignan, (7’E)-(7R,8S)-4-hydroxy-3,5’-dimethoxy-4’,7-epoxy-8,3’-neolig-7’-en-9,9’-diyil diacetate (1), together with two known lignans, (+)-yangambin (2) and (+)-syringaresinol (3), three known triterpenoids, hederatriol (4), basic acid methyl ester (5), and 3β-hydroxyolean-12-en-11-one (6), and four known fatty acid derivatives, cascarillic acid (7), (+)-α-dimorphecolic acid (8), 8(R)-hydroxylinoleic acid (9), and (6Z,9Z,12Z)-pentadecatrienoic acid (10). The structure of the new compound 1 was elucidated by detailed analysis of spectroscopic data and circular dichroism (CD) spectroscopy. Compounds 1, 3-6, and 8-10 isolated from L. acidissima significantly reduced NO production in LPS-stimulated BV-2 microglia cells.  相似文献   

4.
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   

5.
Against the mold mite, Tyrophagus putrescentiae, 3,7-dimethyl-(Z)-2-octenyl formate (II) is the most active compound as an alarm pheromone besides the natural pheromone, neryl formate (I), and this activity is equal to I (1-10 ppm). In order to elucidate the structural requisites for inducing alarm pheromone activity, a total of 16 analogues of I were prepared by modifying the structure of II. For preparation of 3-methyl- and 3-ethyl-(Z)-2-alkenyl formates, the Wittig reaction of ethoxy- or methoxy-carbonylmethylene triphenyl phosphorane with 2-alkanone or 3-alkanone was used. The reaction with 2-alkanone gave a mixture of (Z)-2-alkenoate (ca. 40%) and (E)-2-alkenoate (ca. 60%) in an average 60% yield. The reaction with 3-alkanone gave a mixture of (Z)-2-alkenoate (56%) and (E)-2-alkenonate (44%).

Alarm pheromone activities were demonstrated on 14 compounds of (Z)-2-alkenyl formates. The presence of the (Z)-allylic primary alcohol formate moiety in a molecule was clarified as the key to induce pheromone activity, and no necessity for an acyclic monoterpene carbon skeleton was demonstrated.  相似文献   

6.
Responses of single receptor neurons in the antennae of male Helicoverpa zea to sex pheromone components and to behavioral antagonists were recorded using a cut-sensillum extracellular recording technique. Three types of sensilla were identified from sampling 325 male-specific sensilla trichodea located at the lateral edge of antennomeres. The majority of these sensilla (71%) contained a receptor neuron tuned to the principal sex pheromone component (Z)-11-hexadecenal. A second sensillar type (10%) contained a receptor neuron that responded only to (Z)-9-tetradecenal. A third sensillar type (19%) contained a large-spiking neuron tuned to the secondary pheromone component (Z)-9-hexadecenal, but this neuron also could be stimulated to equivalent spike frequencies by the same emitted amounts of (Z)-9-tetradecenal. A smaller-spiking neuron in this sensillar type responded to two compounds known to act only as behavioral antagonists, (Z)-11-hexadecen-1-ol and (Z)-11-hexadecenyl acetate, and to (Z)-9-tetradecenal. Cross-adaptation studies confirmed the presence of one large- and one small-spiking neuron in the third sensillar type. Dose-response studies correlated to collected stimuli amounts showed that the large-spiking neuron in the third sensillar type was equally tuned to (Z)-9-hexadecenal and (Z)-9-tetradecenal, whereas the smaller-spiking neuron was far more sensitive to (Z)-11-hexadecen-1-ol and to (Z)-11-hexadecenyl acetate than to (Z)-9-tetradecenal. Accepted: 29 September 1997  相似文献   

7.
The non-polar components of female body wax and pheromone gland extracts of the yellow peach moth synergistically enhanced male behavioral responses from close to pheromone sources in wind tunnel tests when mixed with an aldehyde pheromone blend. When the non-polar fractions (NPFs) of female body wax were further separated by column chromatography, synergistic activities were found in the 3 and 50% ether in hexane fractions, and they additively increased male responses. The main components of the first fraction were (Z)-9-tricosene, (Z)-9-pentacosene, (Z)-9-heptacosene, (Z)-9-nonacosene and (Z)-9-hentriacontene. Only (Z)-9-heptacosene showed a significant synergistic effect in enhancing male responses, but the other components had no effect. A mixture of the five monoenyl hydrocarbons lost activity at lower doses than 5 ng. Natural ratios of these hydrocarbons in the female body wax and pheromone gland extracts were similar, but the amount of (Z)-9-heptacosene in the female body wax was significantly higher than in the pheromone gland extracts. We conclude that (Z)-9-heptacosene increases male responses to aldehyde pheromones, and unknown component(s) in the 50% ether in the hexane fraction are required for full synergistic enhancement by the NPFs of the female body wax and the pheromone gland extracts.  相似文献   

8.
(±)-(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   

9.
Single-cell electrophysiological recordings were obtained from olfactory receptor neurons in sensilla trichodea on male antennae of the heliothine species Heliothis subflexa and the closely related congener H. virescens. A large percentage of sensilla (72% and 81%, respectively, of all sensilla sampled) contained a single odor-responsive receptor neuron tuned to the major pheromone component of both species, Z-11-hexadecenal. A second population of sensilla on H. subflexa antennae (18%) housed receptor neurons that were tuned to Z-9-hexadecenal but also responded with less sensitivity to Z-9-tetradecenal. A similar population of sensilla (4%) on H. virescens male antennae housed receptor neurons that were shown to be tuned specifically only to Z-9-tetradecenal, with no response to even high dosages of Z-9-hexadecenal. A third population of sensilla (comprising 8% and 16% of the sensilla sampled in H. subflexa and H. virescens, respectively) housed two olfactory receptor neurons, one of which was tuned to Z-11-hexadecenyl acetate and the other tuned to Z-11-hexadecenol. In H. subflexa the Z-11-hexadecenyl acetate-tuned neuron also responded to Z-9-tetradecenal with nearly equivalent sensitivity. The behavioral requirements of males of these two species for distinct pheromonal blends was, therefore, reflected by the subtle differences in the tuning properties of antennal olfactory receptor neurons.Abbreviations MGC macroglomerular complex - ORN olfactory receptor neuron - Z9–14:Ald (Z)-9-tetradecenal - Z9–16:Ald (Z)-9-hexadecenal - Z11–16:Ac (Z)-11-hexadecenyl acetate - Z11–16:Ald (Z)-11-hexadecenal - Z11–16:OH (Z)-11-hexadecenol  相似文献   

10.
New derivatives of 1,4-dideoxy-1,4-imino-d-ribitol have been prepared and evaluated for their cytotoxicity on solid and haematological malignancies. 1,4-Dideoxy-5-O-[(9Z)-octadec-9-en-1-yl]-1,4-imino-d-ribitol (13, IC50 ∼2 μM) and its C18-analogues (IC50 <10 μM) are cytotoxic toward SKBR3 (breast cancer) cells. 13 also inhibits (IC50 ∼8 μM) growth of JURKAT cells.  相似文献   

11.

The Z- and E-thymine and cytosine pronucleotides 3d, 4d, 3e, and 4e of methylenecyclopropane nucleosides analogues were synthesized, evaluated for their antiviral activity against human cytomegalovirus (HCMV), herpes simplex virus 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), human immunodeficiency virus type 1 (HSV-1), and hepatitis B virus (HBV) and their potency was compared with the parent compounds 1d, 2d, 1e, and 2e. Prodrugs 3d and 4d were obtained by phosphorylation of parent analogues 1d or 2d with reagent 8. A similar phosphorylation of N4-benzoylcytosine methylenecyclopropanes 9a and 9b gave intermediates 11a and 11b. Deprotection with hydrazine in pyridine–acetic acid gave pronucleotides 3e and 4e. The Z-cytosine analogue 3e was active against HCMV and EBV. The cytosine E-isomer 4e was moderately effective against EBV.  相似文献   

12.
Synthesis of “reversed” methylenecyclopropane analogues of nucleoside phosphonates 6a,7a, 6b, and 7b is described. 1-Bromo-1-bromomethylcyclopropane 8 was converted to the bromocyclopropyl phosphonate 9 by Michaelis-Arbuzov reaction with triisopropyl phosphite. Base-catalyzed β-elimination and deacetylation gave the key Z- and E-hydroxymethylcyclopropyl phosphonates 10 and 11 separated by chromatography. The Mitsunobu type of alkylation of 10 or 11 with adenine or 2-amino-6-chloropurine afforded phosphonates 12a, 12b, 13a, and 13b. Acid hydrolysis furnished the adenine and guanine analogues 6a, 7a, 6b, and 7b. The E and Z configuration was assigned on the basis of NOE experiments with phosphonates 6b and 7b. All Z- and E-isomers were also distinguished by different chemical shifts of CH2O or CH2N (H4 or H4′). Significant differences of the chemical shifts of the cyclopropane C3(3’) carbons and coupling constants 3JP,C2(2’) or 3JP,C3(3’) selective for the Z- or E-isomers were also noted. Phosphonates 6a, 7a, 6b, and 7b are devoid of significant antiviral activity.  相似文献   

13.
Three compounds, 20-O-acetyl-[3-O-(2′E,4′Z)-decadienoyl]-ingenol (1), 20-O-acetyl-[5-O-(2′E,4′Z)-decadienoyl]-ingenol (2) and 3-O-(2′E,4′Z)-decadienoylingenol (3), were isolated from Euphorbia kansui under the bioassay-guided method. Each compound showed the same antinematodal activity against the nematode, Bursaphelenchus xylophilus, at a minimum effective dose (MED) of 5 μg/cotton ball.  相似文献   

14.
A new compound, 9-dihydroxyl-2'-O-(Z)-cinnamoyl-7-methoxy-aloesin (1), and eight known compounds (29) were isolated from Aloe vera. Their structures were elucidated using 1D/2D nuclear magnetic resonance and mass spectra. Compound 9 exhibited reversible competitive inhibitory activity against the enzyme tyrosinase, with an IC50 value of 9.8?±?0.9?µM. A molecular simulation revealed that compound 9 interacts via hydrogen bonding with residues His244, Thr261, and Val283 of tyrosinase. Additionally, compounds 3 and 7 were shown by half-leaf assays to exhibit inhibitory activity towards Pepper mild mottle virus.  相似文献   

15.
Six compounds, Z- and E-fadyenolide (3, 4), 1-ally1-2,3-(methylenedioxy)-4,5-dimethoxy-benzene (5), 4-methoxy-3,5-bis (3′-methyl-2′-butenyl)-benzoic acid (6), 2,6-dihydroxy-4-methoxy-dihydrochalcone (7), and 5-hydroxy-7-methoxyflavanone (8) were isolated from three species of Jamaican Piper, Piper fadyenii, C.D.C., Piper aduncum L. and Piper hispidum Sw. Three amides (9 ~ 11) of 3,5-dimethoxy-4-oxo-5-phenylpent-2-enoic acid using piperidine, pyrrolidine and morpholine, respectively, were synthesized from compounds 3 and 4, and tested for insecticidal activity against the tick Boophilus microplus (Canestrini) and the flour feetle, Tribolium confusum Duval. In our experiment, compounds 9 ~ 11 inhibited ovogenesis of B. microplus and were toxic to T. confusum. Compounds 3 ~ 8 were found to have no activity.  相似文献   

16.
Abstract

A novel series of 5-nitro-1H-benzimidazole derivatives substituted at position 1 by heterocyclic rings was synthesized. Cytotoxicity and antiviral activity of the new compounds were tested. Compound 3 was more active than doxorubicin against A-549, HCT-116 and MCF-7. However, compound 3 showed no activity against human liver carcinoma Hep G-2 cell line. Compounds 9 and 17b (E) showed potency near to doxorubicin against the four cell lines. The acute toxicity of compound 9 on liver cancer induced in rats was determined in vivo. Interestingly, it showed restoration activity of liver function and pathology towards normal as compared to the cancer-bearing rats induced by DENA. Compounds 17a (Z), 17b (E) and 18a (Z) were the most promising compounds for their antiviral activity against rotavirus Wa strain.  相似文献   

17.
Uracil has long been known as the main product of nitrosative cytosine deamination in aqueous solution. Recent mechanistic studies of cytosinediazonium ion suggest that the cation formed by its dediazoniation can ring-open to N-protonated (Z,s-cis)-3-isocyanatoacrylonitrile 7. Stereochemical preferences are discussed of the 3-isocyanatoacrylonitriles (Z,s-cis)-10, (E,s-cis)-11, (Z,s-trans)-12, and (E,s-trans)-13. The electronic structures of 7 and 1013 have been analyzed and a rationale is provided for the thermodynamic preference for (Z,s-cis)-10. It is shown that s-cis/s-trans-interconversion occurs via C−N rotation–inversion paths with barriers below 3 kcal mol−1. The proton affinities of 3-isocyanatoacrylonitrile 10 and water are nearly identical and, thus, 3-isocyanatoacrylonitriles can and should be formed in aqueous media from 7 along with 3-aminoacrylonitriles 9. The results highlight the relevance of the chemistry of 3-isocyanatoacrylonitriles for the understanding of the chemical toxicology of nitrosation of the nucleobase cytosine. Electronic Supplementary Material Supplementary Material is available for this article at Dedicated to professor Dr. Paul von Ragué Schleyer on the occasion of his 75th birthday  相似文献   

18.
Ovipositor washings and volatiles from virgin female Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae) were analysed by gas chromatography (GC) linked to electroantennography (EAG). Two EAG responses were observed at retention times consistent with those of monounsaturated 16-carbon aldehydes and monounsaturated 16-carbon alcohols. Analysis of ovipositor washings on high-resolution, capillary GC columns showed peaks which cochromatographed with (Z)-11-hexadecenal, (Z)-9-hexadecenal, (Z)-11-hexadecen-1-ol and hexadecanal. EAG responses of male S. incertulas to synthetic hexadecenal isomers were greatest for the (Z)-11 and (Z)-11 isomers. Field tests in the Philippines showed that traps baited with a mixture of (Z)-11-hexadecenal and (Z)-9-hexadecenal in the naturally occurring 3:1 ratio caught significantly more male S. incertulas moths than those baited with a virgin female moth. Addition of (Z)-11-hexadecen-1-ol to this mixture reduced trap catches.
Résumé Des produits provenant du lavage d l'ovipositeur et des substances volatiles de femelles vierges de S. incertulas Walker (Lep.: Pyralidae) ont été examinées en chromatographie en phase gazeuse (GC) avecélectroantennogramme simultané(EAG). Deux réponses EAG ont été enregistrées à des temps de rétention correspondant à ceux des aldéhydes monoinsaturés 16 carbones et des alcools monoinsaturés 16 carbones. L'analyse des produits provenant du lavage de l'ovipositeur en colonnes GC capillaires à haute résolution a donné des pics correspondant aux (Z)-11-hexadécenal, (Z)-9-hexadécenal, (Z)-11-hexadecen-1-ol et à l'hexadecanal. Les réponses EAG de mâles de S. incertulas aux isomères synthétiques d'hexadécenal étaient plus intenses pour les isomères (Z)-11 et (E)-11. Des essais en champ aux Philippines ont montré que les pièges contenant un mélange de (Z)-11-hexadécenal et de (Z)-9-hexadécenal dans le rapport natural 3/ 1 capturaient plus de mâles de S. incertulas que ceux contenant une femelle vierge. L'addition au mélange de (Z)-11-hexadecen-1-ol réduit les captures.
  相似文献   

19.
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   

20.
An unknown polyacetylene was isolated from the subterranean stems of Solidago altissima L. in which the two poly acetylenes, dehydromatricaria ester (I) and methyl 10-[(Z)-2-methyl- 2-butenoyloxy]-(2Z,8Z)-2,8-decadiene-4,6-diynoate (II) had already been found, and its structure was identified as (4Z)-2,4-decadiene-6,8-diyn-4-olide (dehydromatricaria lactone) (III). The lactone (III), as well as I, strongly inhibited the growth of the seedlings of barnyard millet (Panicum crus-galli L. var. frumentaceum Trin.).

The seasonal variations in the polyacetylene contents of the subterranean stems were closely investigated, with the results that III occurred only in the fall of the year while I and II hardly varied throughout the year. II was a major polyacetylene component and the content was 0.9~1.0 µmol/g fresh wt.  相似文献   

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