首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 609 毫秒
1.
为了寻找新的含2-噻唑基丙烯腈结构的先导化合物,利用2-(4-芳基噻唑-2-基)乙腈与酰氯在吡啶或氢化钠存在下反应,合成了9个2-(4-芳基噻唑-2-基)-3-羟基丙烯腈类化合物,其中8个为新化合物,利用1H NMR、MS和元素分析对其结构进行了表征。初步的生物活性测定结果表明,部分化合物在供试浓度下具有一定的杀虫、杀菌活性,其中化合物 5f 在100 mg/L下对棉花枯萎病菌Fusarium oxysporium的抑制率超过90%,化合物 5e 在250 mg/L下对蚕豆蚜Aphis fabae的致死率达95%。毒力测定结果表明, 5e 对蚕豆蚜的活性优于对照化合物2- -3-羟基-3- 丙烯腈( 6 )。  相似文献   

2.
为探索环境友好新型农药先导化合物,通过水相中酰胺缩合反应合成了16个未见文献报道的七氟异丙基苯基取代的2,2-二氟-1,3-苯并二氧-5-乙酰胺类目标化合物。其结构通过核磁共振氢谱、氟谱以及高分辨质谱确认。初步生物活性测定表明,部分目标化合物对蚕豆蚜虫和粘虫表现出良好的杀虫活性,初步构效关系显示苯环上取代基的种类和位置在化合物的杀虫活性中起关键作用。  相似文献   

3.
BACKGROUND: Pyrazole and hydrazone derivatives possess good insecticidal activities; their substructural units are widely used in pesticide design. In an effort to discover new molecules with good insecticidal activities, a series of pyrazole amide derivatives containing hydrazone substructures were synthesised and bioassayed. RESULTS: Bioassays demonstrated that some of the title compounds exhibited notable control of Plutella xylostella (Linnaeus), Helicoverpa armigera (Hübner), Culex pipiens pallens, Laphygma exigua (Hübner), Spodoptera litura (Fabricius), Nilaparvata lugens (Stål) and Rhopalosiphum maidis (Fitch) at 5, 10, 0.25, 200, 20, 100 and 500 mg L?1 respectively. Comparative molecular field analysis (CoMFA) based on the bioactivities for P. xylostella was studied; the values of q2 and r2 for the CoMFA model were 0.701 and 0.964 respectively. CONCLUSION: Some of the title compounds displayed good and broad‐spectrum insecticidal activities against different insect species; the CoMFA model revealed that a bulky and negatively charged group at the 4‐position of benzene could enhance insecticidal activity. These results could provide useful information for the design of novel insecticide containing substructural units of pyrazole amide and hydrazone. Copyright © 2011 Society of Chemical Industry  相似文献   

4.
为寻找高活性的米尔贝霉素衍生物,以伊维菌素为原料,经脱糖、羟基保护、氧化、还原胺化、脱保护等将其转变为13-氨基米尔贝霉素类似物,通过三组分反应设计合成了一系列米尔贝霉素磺酰脒类化合物(7a~7i),并初步测定了其对朱砂叶螨Tetranychus cinnabarinus和豆蚜Aphis craccivora的室内活性。结果表明:各衍生物对朱砂叶螨和豆蚜均有较好的触杀活性,其中7f、7h和7i对朱砂叶螨24 h的LC50值分别为1.04×10–2、9.60×10–4和1.44×10–2 mg/L;7i对豆蚜24 h的LC50值为7.81 mg/L。米尔贝霉素13位氨基上磺酰化的结构修饰有助于提高米尔贝霉素类化合物的杀螨、杀蚜活性。  相似文献   

5.
吡唑酰胺类杀菌剂是近年新农药开发的热点。本研究采用EDCI/HOBt酰胺化法合成了14个结构新颖的N-(2-三氟甲基-4-氯苯基)-2-吡唑酰氨基环己烷基磺酰胺类化合物 ( 3a ~ 3n ),其结构均经1H NMR、13C NMR、质谱和元素分析确认,并用X-射线衍射法确定了化合物 3g 的单晶结构和立体构型。菌丝生长速率法试验结果表明,化合物 3a 、 3e 和 3j 对番茄灰霉病菌Botrytis cinerea KZ-9的EC50值分别为4.28、10.08和11.31 mg/L,抑菌活性不及对照药剂啶酰菌胺和腐霉利;但在孢子萌发试验中,目标化合物表现出与对照药剂相近的抑菌活性,在10 mg/L下有7个化合物对灰霉病菌孢子萌发的抑制率超过了85%;在番茄活体盆栽试验中,化合物 3e 在200 mg/L下对番茄叶片及其花上灰霉病菌的防治效果分别为77.5%和65.2%,高于对照药剂啶酰菌胺 (防效分别为59.8%和30.3%),有进一步研究的价值。  相似文献   

6.
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   

7.
A series of novel 2-(2,4,6-trisubstituted phenyl)-1,3,4-oxadiazolin-5-one derivatives and 3-(2,4,6-trichlorophenyl)pyrazolin-5-one derivatives were synthesized and evaluated for insecticidal activity. It was found that a moderately bulky alkyl group, such as a tert-butyl group, on the heterocyclic ring, and a trifluoromethyl group on the benzene ring were optimal substituents on the molecule. The oxygen atom in the oxadiazoline ring was essential for insecticidal activity. Of the compounds assayed, 4-tert-butyl-2-(2,6-dichloro-4-trifluoromethylphenyl)-1,3,4-oxadiazolin-5-one gave the highest activity against Nephtotettix cincticeps, with an LC50 value of 0.51 mg litre−1. © 1999 Society of Chemical Industry  相似文献   

8.
井冈羟胺A (validoxylamine A) 作为重要的生物农药中间体具有抑菌和杀虫活性。为开发新型绿色农药,以井冈羟胺A作为先导化合物,通过脂肪酶催化酯化反应,合成了9个未见文献报道的井冈羟胺A酯类衍生物,通过核磁共振氢谱、碳谱以及高分辨质谱对其结构进行了表征。生物活性测定结果表明:大部分目标化合物对立枯丝核菌Rhizoctonia solani具有抑制活性,其中化合物 Ⅰ 的抑制效果最好,EC50值为13.03 μmol/L;化合物 Ⅶ 在500 mg/L下对豆蚜Aphis craccivora的致死率为64.60%。该类衍生物具有一定的抑菌、杀虫活性,有进一步研究的价值。  相似文献   

9.
A methanol extract of roots of Lasiosiphon kraussianus (Meisn) (Thymelaeaceae) showed potent insecticidal activity against Aphis gossypii (Glov) and Drosophila melanogaster (Meig). Bioassay-driven fractionation of this extract led to the isolation and characterisation of two known daphnane diterpenoids: Excoecaria toxin (1) and wikstrotoxin D (2) . The two natural products were inferior to methomyl in activity against A gossypii and Myzus persicae (Sulz) in contact assays but were superior in ingestion assays against D melanogaster. This is the first report on insecticidal activities of compounds 1 and 2 . AChE was insensitive to the two natural products. © 1999 Society of Chemical Industry  相似文献   

10.
In order to find the biorational pesticides, eight novel 4β-substituted phenoxyaniline derivatives of podophyllotoxin have been synthesized with significant stereoselectivity and improved yields by employing the BF3·Et2O/NaI reagent system and evaluated for their antifeedant effect against 5th instar larvae of Pieris rapae and effect on the development of 5th instar larvae of P. rapae as well as for insecticidal activity against P. rapae. The antifeedant activities showed that these compounds exhibited less potent than podophyllotoxin. Though these derivatives showed less potent antifeedant activities than podophyllotoxin, they acted as growth development inhibitor to 5th instar larvae of P. rapae, which were found that the animals treated with podophyllotoxin and its derivatives showed moulting disturbances and/or deformities. Also, the insecticidal activity results show that all of these derivatives of PPT showed delayed insecticidal activity, which differs from traditional neurotoxic insecticides. Among them, compounds possessing a 4β-phenoxyaniline moiety substituted (CO2C2H5, Cl and OH) at para position exhibited greater insecticidal activity against P. rapae than podophyllotoxin.  相似文献   

11.
为了寻找和发现高效、广谱、低毒、低生态风险并与现有杀虫剂无交互抗性的新型杀虫剂,以2-氯-5-氯甲基噻唑为原料,经多步反应制得10个新型N-氰基甲基 砜亚胺类化合物,其结构均经核磁共振氢谱、元素分析确证。室内生物活性测试结果表明,目标化合物对桃蚜Myzus persicae具有一定的杀虫活性,其中化合物 7-1 在质量浓度为10 mg/L下对桃蚜的致死率达到80%。  相似文献   

12.
In an attempt to find the biorational pesticides, we synthesized 12 pyridinyl derivatives of podophyllotoxin (PPT) and 4′-demthylepipodophylltoxin (4′-DMEP) in this study. Their structures and the α/β substitution at C-4 were confirmed by 1H NMR, IR, MS spectral analyses and elemental analysis. The insecticidal activities were tested against fifth-instar larvae of Pieris rapae and the third-instar larvae of Cullex pipiens pallens at concentrations of 250 and 10 μg ml−1. Four derivatives of PPT, 4.1, 4.2, 4.3 and 4.5, showed higher insecticidal activities against P. rapae than PPT, while three derivatives of PPT, 4.4, 4.5 and 4.6, displayed higher mosquito larvicidal activity than PPT, with LC50 values of 1.66, 3.96 and 1.54 mg l−1, respectively. Interestingly, we also found that the pyridine ring derivatives of PPT showed delayed insecticidal activity, which is different from traditional neurotic insecticides. The results suggest that 4′-OCH3 in the PPT derivatives is essential to keep the insecticidal activity and the insecticidal activities of pyridine ring derivatives of PPT are higher than that of the derivatives of 4′-DMEP, supporting PPT has the potential to be a lead structure of semi-synthetic insecticides.  相似文献   

13.
为了寻找高活性的新化合物,通过相转移催化反应,在二氯甲烷/水体系中合成了一系列新的吡啶杂环硫代磷酸酯类化合物,其结构均经1H NMR、13C NMR、31P NMR、IR和MS的表征,并通过元素分析确证。室内生物活性测试结果表明,部分化合物表现出较好的杀虫活性,其中化合物 3a 对苜蓿蚜Aphis medicaginis Koch和化合物 3c 对东方粘虫Mythimna separate的 LC50值分别为 1.64和 0.73 mg/L,与对照药剂毒死蜱的活性相当。  相似文献   

14.
1,5-Diphenyl-1-pentanone (A) and 1,5-diphenyl-2-penten-1-one (B) are natural products extracted from Stellera chamaejasme. Laboratory bioassay revealed the two compounds showed strong insecticidal activity against Aphis gossypii Glov.The two compounds may represent a novel class of aphicides due to their shared distinctive structure of 1,5-diphenyl-1-pentanone. In the present study, 1,5-diphenyl-1-pentanone analogues were synthesized in an effort to examine their structure activity. Insecticidal activities of these compounds against A. gossypii Glov. were also evaluated.  相似文献   

15.
BACKGROUND: Spiromesifen is a novel insecticidal/acaricidal compound derived from spirocyclic tetronic acids that acts effectively against whiteflies and mites via inhibition of acetyl‐CoA‐carboxylase, a lipid metabolism enzyme. The effects of spiromesifen on the developmental stages of the whitefly Bemisia tabaci (Gennadius) were studied under laboratory conditions to generate baseline action thresholds for field evaluations of the compound. RESULTS: Adult B. tabaci mortality rate after spiromesifen treatment (5 mg L?1) was 40%. Treatment with 0.5 mg L?1 reduced fecundity per female by more than 80%, and fertility was almost nil. LC50 for eggs was 2.6 mg L?1, and for first instar 0.5 mg L?1. Scanning electron microscopy revealed that eggs laid by treated adult females had an abnormally perforated chorion, and females were unable to complete oviposition. Light and fluorescent microscopy showed significantly smaller eggs following treatment, and smaller, abnormally formed and improperly localized bacteriomes in eggs and nymphs. The number of ovarioles counted in females treated with 5 mg L?1 was significantly reduced. Spiromesifen showed no cross‐resistance with other commonly used insecticides from different chemical groups, and resistance monitoring in Israel showed no development of field resistance to this insecticide after 1 year of use. CONCLUSION: The strong effect on juvenile stages of B. tabaci with a unique mode of action and the absence of cross‐resistance with major commonly used insecticides from different chemical groups suggest the use of spiromesifen in pest and resistance management programmes. Copyright © 2008 Society of Chemical Industry  相似文献   

16.
以芳氧吡啶乙酮分子插件为基础,设计合成了一系列芳氧吡啶乙酮肟醚类化合物,其结构经核磁共振氢谱、碳谱及高分辨质谱等确证。初步杀虫活性测定结果表明,该系列化合物对棉蚜 Aphis gossypii (Glover) 具有较好的杀虫活性,其中化合物 5a 和 6i 在50 μg/mL下对棉蚜的致死率分别为76.8%和70.1%,具有作为先导化合物进一步研究的价值;但其对小菜蛾的杀虫活性较差,在100 μg/mL下的致死率普遍低于30%。该系列化合物主要体现出了新烟碱类化合物的活性特征,为进一步研究其构效关系提供了新思路。  相似文献   

17.
BACKGROUND: The lead coumarin derivative (E)‐methyl 3‐methoxy‐2‐[2‐(4‐methylcoumarin‐7‐yloxymethyl)phenyl]acrylate was discovered by using an intermediate derivatisation method. To discover new coumarin derivatives with improved activity, a series of substituted coumarins were synthesised and bioassayed. RESULTS: The compounds were identified by 1H NMR, IR, MS and elemental analysis. Bioassays demonstrated that some of the title compounds exhibited excellent fungicidal activity against cucumber downy mildew at 25 mg L?1. The relationship between structure and fungicidal activity is reported. CONCLUSION: The present work demonstrates that coumarin derivatives containing methoxyacrylate moieties can be used as possible lead compounds for developing novel fungicides. Copyright © 2011 Society of Chemical Industry  相似文献   

18.
BACKGROUND: Phthalic acid diamide derivatives are among the most important classes of synthetic insecticides. In this study, a 3,3‐dichloro‐2‐propenyloxy group, the essential active group of pyridalyl derivatives, was incorporated into phthalic acid diamide derivatives with the aim of combining the active groups to generate more potent insecticides. RESULTS: Thirty‐one new phthalic acid diamides were obtained, and these were characterised by 1H and 13C NMR. The structure of N2‐[1,1‐dimethyl‐2‐(methoxy)ethyl]‐3‐iodo‐N1‐[4‐(3,3‐dichloro‐2‐propenyloxy)‐3‐(trifluoromethyl)phenyl]‐1,2‐benzenedicarboxamide was determined by X‐ray diffraction crystallography. The insecticidal activities of the compounds against Plutella xylostella were evaluated. The title compounds exhibited excellent larvicidal activities against P. xylostella. Structure‐activity relationships revealed that varying the combination of aliphatic amide and aromatic amide moieties, or the nature and position of substituent Y on the aniline ring, could aid the design of structures with superior performance. CONCLUSION: A series of novel phthalic acid diamides containing a 3,3‐dichloro‐2‐propenyloxy group at the 4‐position of the aniline ring were designed and synthesised. Structure‐activity relationships with the parent structure provided information that could direct further investigation on structure modification. Copyright © 2012 Society of Chemical Industry  相似文献   

19.
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   

20.
2-噻唑酰氨基环己烷基磺酰胺的合成与杀菌活性   总被引:1,自引:1,他引:0  
为进一步研究环烷基磺酰胺类化合物的杀菌活性与构效关系,在前期工作基础上,合成了11个未见文献报道的2-噻唑酰氨基环己烷基磺酰胺类化合物 ( 7a ~ 7k ),其结构均经1H NMR、13C NMR、质谱和元素分析确证。分别采用菌丝生长速率法、黄瓜活体叶片法、孢子萌发法和番茄活体盆栽法对目标化合物进行了生物活性测定。结果表明:目标化合物对番茄灰霉病菌Botrytis cinerea表现出较好的抑制活性,其中化合物 7a 和 7c 在10 mg/L下对番茄灰霉病菌孢子萌发的抑制率分别为90%和67%;在200 mg/L 施药剂量下,对活体黄瓜叶片、番茄叶片和番茄花上灰霉病的防治效果,化合物 7a 分别为75%、78%和30%,化合物 7c 分别为78%、62%和44%,均优于对照药剂腐霉利,有进一步研究的价值。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号