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1.
以3-氨基-2-氯吡啶(1)为起始原料,经重氮化、叠氮化、环合和酰氯化反应,生成1-(2-氯吡啶-3-基)-5-甲基-1H-1,2,3-三唑-4-甲酰氯(5),(5)与取代苯胺反应,制得13个未见文献报道的吡啶联三唑类化合物,其结构通过 1H NMR和LC-MS表征。初步生物活性测定结果表明:在500 mg/L质量浓度下,所有目标化合物对粘虫 Mythimna separate 均有一定的杀虫活性,部分化合物致死率达100%;但在100 mg/L下,除化合物ZJ-7的致死率仍达100%外,其余化合物的活性明显降低,甚至无活性。  相似文献   

2.
BACKGROUND: In recent years, many studies have been carried out on the behavioural and electrophysiological responses of Cydia pomonella (L.) to host volatile emissions, to find alternative attractants to the sex pheromone for pest monitoring. These studies have focused on apple and pear, and very little has been done on walnut. In the present work, the diurnal and seasonal variation in walnut volatile emissions and the electrophysiological response of C. pomonella have been studied. RESULTS: Ninety compounds were detected in walnut emissions, mainly monoterpenes and sesquiterpenes. The most abundant compound was β‐pinene, which, together with (Z)‐3‐hexenyl acetate, (E)‐β‐ocimene, limonene, germacrene D, 1,8‐cineole, sabinene, (E)‐β‐farnesene, (E)‐β‐caryophyllene, β‐myrcene and β‐phellandrene, constituted between 81.9 and 90.5% of the total chromatographic area. Differences between seasonal periods were significant for 39 compounds, and between daytimes for 14 compounds. Discernible and consistent EAD responses were detected to 11 walnut‐origin compounds, and confirmed with synthetics to seven of them. Except for alloocimene, pinocarvone and caryophyllene oxide, all these compounds are also emitted by apple. CONCLUSION: Walnut volatile emissions differ widely from apple ones, but both share many compounds that are EAD‐active in C. pomonella. However, among EAD‐active compounds there are three walnut‐specific ones, which should be further tested in behavioural assays. Copyright © 2008 Society of Chemical Industry  相似文献   

3.
BACKGROUND: The development of environmentally friendly and novel structural pesticides is now an area of intense research in the agriculture field. Spirocyclic tetronic acids such as spiromesifen are typical compounds of this kind. In order to discover novel compounds with improved and broader-spectrum insecticidal activities, a series of spiromesifen derivatives were synthesised and bioassayed. RESULTS: The derivatives were identified by 1H NMR and MS. Preliminary bioassays demonstrated that some bioactivities of compounds 5a to 5u were better and had a broader spectrum than the lead compound spiromesifen. Moreover, these compounds showed better insecticidal activities against Mythimna sepatara and Aphis fabae than acaricidal activities against Tetranychus cinnabari. Furthermore, LC50 of 5s against Aphis fabae reached 1.09 mg L−1. At the same time, compounds 5g, 5i, 5k and 5r also warrant further study because of their superior bioactivities to spiromesifen. What is more, suitable carbon chain length in the 4-position ester and the log P value of these spiromesifen derivatives dramatically influenced their insecticidal activities. Butyric or pentanoic ester and a log P value of 4.0–6.0 may be preferred. CONCLUSION: The present work demonstrates that some spiromesifen derivatives can be used as potential lead compounds for developing novel insecticides and acaricides. Copyright © 2011 Society of Chemical Industry  相似文献   

4.
为探索新的农药先导化合物,经取代苯基呋喃甲酰氯与5-肼基-3(2H)哒嗪酮反应,得到15个未见文献报道的含呋喃环3(2H)哒嗪酮类化合物,其结构均通过了红外光谱、核磁共振氢谱和元素分析确认。初步生物活性测定结果表明,目标化合物具有良好的杀菌活性,但杀虫活性较弱。其中化合物3k在50 mg/L时对灰霉病菌的抑制率为86.29%±1.51%,与对照药剂腐霉利相当。初步的构效关系研究结果显示,苯环上取代基的种类和位置对杀菌活性有重要影响。  相似文献   

5.
Tan spot caused by Pyrenophora tritici‐repentis is a disease present in all wheat‐producing countries and silicon (Si) treatment of wheat plants has been shown to increase plant resistance to tan spot. In this study, the effect of phenylpropanoid metabolism on resistance to tan spot was evaluated and some phenolic compounds that accumulated in response to P. tritici‐repentis attack were identified. Furthermore, the effect of Si on phenylalanine ammonia‐lyase (PAL) activity and phenolic compound accumulation were determined in situ. Antifungal activity of differentially accumulated phenolic compounds was also evaluated in in vitro tests. Results showed that the increase in concentration of phenolic compounds was greatest at the onset of infection, and that some compounds showed fungitoxic effects including fungal tip swelling, granulation of germ tube and hyphae, and hyphal hyperbranching. Silicon‐induced reduction in both lesion size and tan spot disease progression were associated with activation of phenylpropanoid metabolism. PAL activity and accumulation of antifungal phenolic compounds were greater in pathogen‐inoculated plants supplied with Si. In these plants, fluorescence indicative of accumulation of phenolic compounds occurred early in epidermal cells and its intensity increased during the evaluation period, showing higher numbers of fluorescent cells around infected cells. Thus, the combined responses of cell fluorescence at sites of infection, increased PAL activity and accumulation of phenols indicate that Si strengthened wheat defence responses to infection by P. tritici‐repentis, reducing the severity of tan spot.  相似文献   

6.
2-氧代-2-苯基乙磺酰胺化合物组合合成与杀菌活性研究   总被引：2，自引：2，他引：0  
为了快速获得具有高效杀菌活性的先导化合物,利用组合化学与传统合成方法相结合的方案,研究了N-取代-2-氧代-2-苯基乙磺酰胺类化合物对灰霉病菌的杀菌活性。首先以苯乙酮为原料,经过磺化、氯化反应,制备得到2-氧代-2-苯基乙磺酰氯,再分别与苯胺、苄胺和烷基胺组合库反应,制备了33个组合库,其中包含105个化合物,收率在60%~90%之间,纯度在70%~95%之间。筛选其中的10个活性库进行平行合成,得到29个化合物,又对其中10个活性化合物进行了纯化与结构鉴定。最后用灰霉病菌Botrytis cinerea对所有组合库与化合物进行离体与活体双重筛选,快速确定了高活性先导化合物,为进一步的结构优化奠定了基础。  相似文献   

7.
A series of bromo-, hydroxy- and keto-derivatives of norbornane-6-hydroxy-2-carboxylic acid, y-lactone and some related compounds have been prepared and examined for phytotoxic activity. The 3-exo-propionyl, and 3-exo-5-exo-dibromo substituted compounds have been found to have the greatest activity.  相似文献   

8.
Yuji Oka 《Plant pathology》2021,70(4):912-921
The attractiveness of 60 aromatic compounds, mainly carboxylic acids, alcohols, aldehydes, and phenols, to second-stage juveniles (J2) of four Meloidogyne species (M. hapla, M. incognita, M. javanica, and M. marylandi) was evaluated based on the relative density of J2 attracted to a test compound on an agar plate in an 8.5-cm Petri dish. Three types of nematode responses were observed in the single-compound assays: attraction, in which J2 were attracted to test compounds; concentration-dependent attraction, in which J2 were attracted to the zone located 1–2 cm from test compounds; and no response. None of the test compounds effectively attracted M. incognita or repelled J2 of any species. Thirty-five compounds attracted J2 of at least one of the other three nematode species. Highly effective attractants were trans-cinnamic acid, salicylic acid, 4′-hydroxy-3′-methoxyacetophenone, o-vanillin, carvacrol, 3-methoxybenzyl alcohol, 2-methoxycinnamaldehyde, trans-p-methoxycinnamaldehyde, 4-methoxy-3-methylbenzaldehyde, 2-methoxy-4-propenylphenol, and thymol. Salicylic acid dissolved in the agar reduced the attraction of M. marylandi J2 to salicylic acid and to o-vanillin. Two- and three-compound assays revealed differences in attractiveness to M. marylandi J2 between or among structural isomers of the attractants. o-Vanillin and salicylic acid were much more attractive to M. marylandi than vanillin and the two isomers of salicylic acid, respectively. It is not clear whether nematodes utilize the attractants found in the study for locating hosts in nature, but the attractants may have potential for use in nematode control.  相似文献   

9.
The role of multiple ATP-binding cassette (ABC) and major facilitator superfamily (MFS) transporter genes from the plant pathogenic fungus Botrytis cinerea in protection against natural fungitoxic compounds was studied by expression analysis and phenotyping of gene-replacement mutants. The expression of 11 ABC (BcatrA–BcatrK) and three MFS genes (Bcmfs1, Bcmfs2 and Bcmfs4) was studied. All genes showed a low basal level of expression, but were differentially induced by treatment with cycloheximide and the plant defence compounds camptothecin, eugenol, psoralen, resveratrol and rishitin. The latter compounds induced expression of BcatrB at a high level. Eugenol was more toxic to BcatrB gene-replacement mutants than to the control isolates. Eugenol also caused an instantaneous increase in mycelial accumulation of the fungicide fludioxonil, a known substrate of BcatrB. However, there was no difference in virulence between the wild-type and BcatrB gene-replacement mutants on Ocimum basilicum, a plant known to contain eugenol. The results indicate that BcatrB is a transporter of lipophilic compounds, such as eugenol, but its role in virulence remains uncertain.  相似文献   

10.
李元祥 《农药学学报》2011,13(6):645-648
以水杨醛为原料,经取代、加成和消除反应合成了6个标题化合物(3a~3f),其中4个(3a~3d)为新化合物,其结构经核磁共振氢谱、质谱和元素分析确认。初步的除草活性测试结果表明,在有效成分150 g/hm2的剂量下,除化合物3f对稗草Echinochloa crus-galli的抑制率为55%外,其余5个化合物对供试杂草的抑制率均在80%以上,部分化合物对稗草、早熟禾Poa annua、反枝苋Amaranthus retroflexus或小藜Chenopodium album的抑制率达100%。  相似文献   

11.
The bactericidal and fungicidal activities of aspyrone and asperlactone, secondary metabolites of Aspergillus ochraceus, and some aspyrone derivatives were studied. In general, aspyrone exhibited better activity than asperlactone or aspyrone derivatives. The inhibition patterns of the assayed compounds were different. Helminthosporium monoceras was the tested mould most inhibited by the studied compounds. The comparative study of the activity of the different compounds showed that the epoxy group seems to be necessary for activity against some micro-organisms. © 1998 SCI  相似文献   

12.
The susceptibility of web-building and hunting spiders from the tropics (Panama), Europe (F.R. of Germany) and the Middle East (Israel) to 30 pesticides (16 insecticides, 4 acaricides, 1 herbicide, 9 fungicides) was determined. Laboratory test methods for juvenile and adult web-building spiders are described.Philodromus sp. (hunting spider), was completely resistant to all substances;Argiope sp. (web-building spider),Linyphia sp. (web-building spider) andChiracanthium sp. (hunting spider) showed medium to high susceptibility. Insecticides affected spiders in a wide range of responses: from no mortality (most compounds of biological origin) and medium mortality (pyrethrin compounds, organophosphorus and carbamate compounds), to high mortality (cyclo compounds). To both groups of spiders (the hunting and web-building), most acaricides were highly toxic, whereas herbicides and fungicides were nontoxic.  相似文献   

13.
BACKGROUND: 1,3‐Dichloropropene (1,3‐D, CAS No. 542‐75‐6) is a broad‐spectrum soil fumigant used to control numerous species of soilborne plant‐parasitic nematodes. 1,3‐D consists of two isomers, (Z)‐ and (E)‐1,3‐D. There are a number of low‐level chlorinated compounds that could potentially be produced as a part of the 1,3‐D manufacturing process. 1,3‐D and its metabolites, as well as potentially related chlorinated compounds, represent potential groundwater contaminants. RESULTS: This study has investigated the hydrolytic stability, under biotic and abiotic conditions in the laboratory, of an extensive representative list of 1,3‐D and potentially related chlorinated compounds in order to predict their environmental fate. All of these compounds showed intrinsic hydrolytic instability under both abiotic and biotic test conditions. Furthermore, a monitoring programme was carried out. Twenty‐five wells were monitored in five Italian regions characterised by historical and existing use of 1,3‐D. The parent compound, its two major metabolites and potentially related chlorinated compounds were not detected in the well water at > 0.1 µg L?1 at any sampling location. CONCLUSION: The soil fumigant (E,Z)‐1,3‐D, its metabolites and potentially related chlorinated compounds constitute a low risk to groundwater. Copyright © 2011 Society of Chemical Industry  相似文献   

14.
The phenolic composition of olive roots and stems was studied by high performance liquid chromatography–mass spectrometry. The in vivo levels of the principal phenolic compounds found in olive plants infected by Phytophthora megasperma Drechsler and Cylindrocarpon destructans (Zinssm.) Scholten differed from the levels observed in non-infected plants. When the antifungal activity of these compounds against both fungi was studied in vitro, the most active were quercetin and luteolin aglycons, followed by rutin, oleuropein, p-coumaric acid, luteolin-7-glucoside, tyrosol and catechin. Microscopic study showed that these phenolic compounds affected the growth, morphology and ultrastructure of the fungi. Taken together, these findings suggest that the phenolic compounds present in olive plants play an active role in the protection against pathogen attack.  相似文献   

15.
Acidovorax citrulli is a seed-transmitted gram-negative bacterium that can cause substantial economic yield loss in watermelon and melon production worldwide. Four small-molecule libraries containing 4,952 compounds were selected for high-throughput screening against A. citrulli wild-type strain Xu3-14 by evaluation of growth inhibition. One hundred and twenty-seven molecules (2.5% hit rate) were identified as bactericidal or bacteriostatic against A. citrulli at 100 μM. Secondary screens indicated that 27 candidate compounds were more effective against A. citrulli Group II strains than Group I strains (classified using repetitive element PCR). Several compounds were inhibitory to other pathogenic bacteria, including Clavibacter michiganensis subsp. michiganensis and Xanthomonas campestris pv. campestris, but did not affect the growth of plant beneficial bacteria Pseudomonas fluorescens and Bacillus subtilis. More than half of the compounds did not inhibit germination of Arabidopsis or watermelon seeds. The effect of small molecules on A. citrulli seed-to-seedling transmission was evaluated by applying each compound to inoculated watermelon seeds and assessing seedling infection. Nine compounds were chosen for further investigation based on their reduction of percentage seedling infection and compiling scores on their specificity, sensitivity, and phytotoxicity obtained in the secondary screens. The five best compounds were selected (thiamphenicol, nadifloxacin, pipemidic acid, ciclopirox, and zinc pyrithione) for greenhouse tests and were found to effectively reduce the seed-to-seedling transmission of A. citrulli in both artificially and naturally infested seeds. These top five compounds provide a basis for future development of an A. citrulli-specific bactericide.  相似文献   

16.
Twenty-seven ethers which are structural analogues of DDT-pyrethroid insecticides have been synthesised. Bioassay data for these compounds against Lucilia cuprina, Blatella germanica and Heliothis punctigera are presented and the structure-activity relationships (SAR) discussed. The SAR of the new series of ether analogues are compared and contrasted to those of their parent DDT-pyrethroid compounds.  相似文献   

17.
Data are presented on changes in physical properties and insecticidal activity resulting from modifications in chemical structure in two groups of compounds. The first group consists of propoxur and three closely related N-methylcarbamates and the corresponding N-acetyl compounds The parent compounds are all highly toxic to adult mosquitos by topical application in solution and deposits from water-dispersible powder formulations on plywood and plaster of Paris panels have long residual activity. N-acetylation is not accompanied by excessive loss of toxicity to mosquitos, but increases volatility to the extent that none of the four N-acetyl derivatives can be considered as potential residual insecticides. The second group consists of tetrachlorvinphos and related vinyl phosphates and vinyl phosphorothionates which show a wide range of toxicity both to adult mosquitos and to mammals.  相似文献   

18.
以2,3-二氯吡啶为起始原料,经肼基化、环合、氧化、取代、水解、环合和胺解反应,合成了15个文献未见报道的新型含单氟甲氧基的吡唑邻甲酰氨基苯甲酰胺类化合物,其结构通过核磁共振氢谱和高分辨质谱确认。初步的杀虫活性测试结果显示,所有目标化合物在100 mg/L下对粘虫Oriental armyworm的致死率均为100%,当测试浓度降低至4 mg/L时,化合物 8a 、 8d 、 8g 、 8k 和 8n 的致死率仍为100%,值得进一步研究。  相似文献   

19.
The relationship between the hydrophobicity of certain herbicidal compounds and the bleaching pattern caused on radish cotyledons was investigated. Seed treatment with diphenylpyridones, as well as with established herbicides, produced three types of bleaching pattern according to their hydrophobicity. The less hydrophobic compounds caused complete bleaching of both cotyledons, but the compounds with more hydrophobicity caused only partial bleaching. The critical points for whole or partial bleaching were in the range of log Kow 4–5 (Kow: octanol/water partition coefficient), and these values were changed slightly with their chemical classes. Uptake of compounds into the seed coat took place rapidly; these compounds were then translocated slowly from the seed coat to the embryo, namely, radicle, abaxial surface of one cotyledon and marginal areas of both cotyledons. Application of these compounds to roots resulted in initial translocation to marginal areas of both cotyledons, with subsequent translocation to the middle area. It is believed that compounds taken up into the radicle were translocated to both cotyledons in a manner similar to that following application to roots. These effects following uptake by seeds can be used as a translaminal and lateral transport assay for bleaching herbicidal compounds in cotyledons.  相似文献   

20.
Cassia alata (Caesalpiniaceae), an ornamental shrub, has many biological properties such as antifungal and antibacterial activities. Several bioactive and phytotoxic compounds have already been isolated from C. alata. Phytotoxic substances from plants have drawn attention as an alternative biological approach to control weeds. Thus, we conducted this research to explore other phytotoxic compounds in C. alata leaves. Aqueous methanol extracts of C. alata leaves strongly inhibited the seedling growth of broccoli, cabbage, cress, radish and rapeseed, in which the level of inhibition correlated with concentration. Two active compounds were isolated through chromatographies and identified using spectral data as (S)‐4‐(3‐hydroxybutyl)phenol [(+)‐rhododendrol] and (E)‐4‐((1R,4R)‐4‐hydroxy‐2,6,6‐trimethylcyclohex‐2‐en‐1‐yl)but‐3‐en‐2‐one [3‐hydroxy‐α‐ionone]. These two active compounds inhibited the growth of cress seedlings in a concentration‐dependent manner. The required concentrations for 50% growth inhibition (I50 value) of cress seedlings were 192.0–296.1 μM for (+)‐rhododendrol and 132.4–195.3 μM for 3‐hydroxy‐α‐ionone. These results indicate that the two phytotoxic compounds play a part in the phytotoxic activity of C. alata leaves.  相似文献   

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