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1.
针对25个噁唑烷类化合物,以玉米根部GST活性为衡量标准,运用三维定量构效关系中的比较分子力场分析(CoMFA)和比较分子相似性指数分析(CoMSIA)两种方法进行研究;应用20个化合物作为训练集,分别建立相应的模型,并对其进行结构和活性关系的分析。CoMFA模型的交叉验证系数q2为0.647,非交叉验证系数r2为0.999;CoMSIA模型交叉验证系数q2为0.527,非交叉验证系数r2为0.949。使用训练集以外的5个化合物进行了验证,两种模型预测值与实测值偏差较小,都显示出了较好的预测性和稳定性。研究结果可为设计新的噁唑烷类潜在的除草剂安全剂提供可靠信息。  相似文献   

2.
采用玻片浸渍法,测定并筛选了25种具有代表性的香豆素类化合物对朱砂叶螨Tetranychus cinnabarinus雌成螨的触杀活性,并构建了一个预测能力较强的定量构效关系(QSAR)模型。结果表明:所有供试化合物对朱砂叶螨均具有触杀活性,且随着处理时间的延长活性升高。处理48 h后,LC50值低于1000 mg/L的化合物有8个,分别是3-(2-苯并咪唑)-7-(二乙氨基)香豆素(1)、3-(2-苯并噻唑)-7-(二乙氨基)香豆素(2)、3-氨基香豆素(3)、3-乙酰基香豆素(4)、4-甲氧基香豆素(5)、6-硝基香豆素(8)、6,7-二甲氧基香豆素(13)和7,8-二羟基香豆素(21),其中化合物1、2、3、5和13的杀螨活性优于药剂对照螺螨酯或与其活性相当;活性最好的化合物为13,处理48 h和72 h后LC50值分别为284.8和122.2 mg/L,其毒力约为螺螨酯的2倍。通过计算得到25种香豆素类化合物的34种物化参数,以此为描述子,经过SPSS相关性剔除、逐步回归分析和校正,得到一个以扭转力、取向力、总能量和分子半径为自变量的QSAR模型,该模型复相关系数R达到0.987,复判定系数R2也达到0.967,通过F检验证明上述模型具有较高的预测能力。  相似文献   

3.
定量构效关系在农药设计合成中的应用进展   总被引:5,自引:0,他引:5  
本文介绍了定量结构-活性关系(QSAR)的基本原理,重点评述了其中比较分子力场分析法(CoMFA)的主要理论及用该法建立QSAR模型的步骤,以及QSAR在农药合成设计中的应用进展。  相似文献   

4.
氨基甲酸酯类农药被广泛用于农业生产中,其作用机理主要是通过与乙酰胆碱酯酶共价结合,从而抑制其正常的生物活性,但此类农药的无节制使用导致其大量残留于生态环境中,对整个生态系统的生存安全造成了严重威胁.本文作者基于量化反应性指数,采用遗传/偏最小二乘法,对氨基甲酸酯与其对乙酰胆碱酯酶的抑制活性进行了定量构效关系研究.结果表...  相似文献   

5.
刘瑾林  周红  郭富友  丁伟 《农药学学报》2019,27(5-6):692-708
香豆素类化合物是自然界广泛存在的一类具有苯并α-吡喃酮结构的天然化合物,具有抗癌、抗菌、抗炎和抗氧化等生理活性,同时也具有良好的杀虫、杀菌等农用活性。近年来研究表明,香豆素类化合物的杀螨活性更为突出,而且具有独特的作用靶标,具有开发成新型杀螨剂的潜力。本文综述了香豆素类化合物及其衍生物的杀虫、杀螨和抑菌活性,重点介绍了具有杀螨活性的香豆素类化合物的结构修饰、构效关系以及东莨菪内酯等对朱砂叶螨Tetranychus cinnabarinus的作用机制,明确其杀螨活性的主要作用靶标是新型的钙离子通道相关的G蛋白偶联神经肽受体 (TcGPCR)。这些研究进展为以香豆素类化合物为模板、以钙离子通道为靶标的新型植物性杀虫、杀螨剂的创制提供了重要基础。  相似文献   

6.
蜕皮激素及其类似物具有调节昆虫蜕皮、变态和繁殖的功能。蜕皮激素类似物在农业生产,尤其是鳞翅目害虫的防治中发挥着重要作用。总结近期的文献,同时结合课题组的工作,综述了蜕皮激素类似物的定量构效关系、蜕皮激素受体三维结构的研究进展。  相似文献   

7.
利用 Hansch方法定量地研究了 2 0种磺酰脲和 16种嘧啶磺酰胺除草剂的结构与活性间关系。结果表明这两类化合物的构效关系是一致的 ,这意味着它们能作用于靶标的同一部位。影响化合物活性的主要因素是分子的电性 ,它们与受体作用时具有一个最佳电性值 (Σσ或 p Ka)。  相似文献   

8.
以取代苯甲酸为起始原料,与氨基硫脲、三氯氧磷及取代苯甲酰氯进行缩合,制备了33个2-取代苯基-5-取代苯甲酰胺基-1,3,4-噻二唑 E 1 ~E 33 。采用核磁共振氢谱 (1H NMR) 和高分辨质谱 (HRMS) 等对目标化合物的结构进行了确证及表征。采用菌丝生长速率法测定了目标化合物对根霉Rhizopus nigricans、青霉Penicillium glaucum、灰霉Botrytis cinerea、交链孢霉Alternaria brassicae和黑曲霉Aspergillus niger的体外抑菌活性。针对黑曲霉的抑制活性,分别利用CoMFA和CoMSIA对目标化合物进行了初步的三维定量构效关系 (3D-QSAR) 研究。结果表明,大部分化合物表现出良好的抑菌活性,在50 μg/mL下,化合物 E 1 、 E 2 和 E 29 对供试真菌的抑制率均达到80%以上,与对照药剂百菌清和多菌灵的抑菌效果相当。综合两种模型的结果,发现静电场的贡献值高于其他势场,且当苯环a的4位引入供电子基、苯环a的2位和6位以及苯环b上引入吸电子基时,有利于化合物抑菌活性的提高,可为进一步指导设计合成此类高活性化合物提供理论依据。  相似文献   

9.
二芳酰肼类化合物是近年来开发的具有蜕皮激素活性的非甾醇类昆虫生长调节剂,能引起昆虫,特别是鳞翅目幼虫早熟、不完全、致死性蜕皮。文章总结近期文献,结合课题组的研究工作,对该类化合物中各个结构片断对其杀虫活性的影响进行了探讨,对结构与活性的关系进行了综述。  相似文献   

10.
为获得活性更佳且同时具备苯甲酰基脲类和氨基甲酸酯类活性的新型双靶标杀虫剂——N-氯磺基-N-甲基氨基甲酸酯衍生物,构建此类化合物的三维定量构效关系(three-dimensional quantitative structure-activity relationship,3D-QSAR)模型,以18种具有双靶标活性的N-氯磺基-N-甲基氨基甲酸酯衍生物为训练集,分别采用比较分子力场分析(comparative molecular field analysis,CoMFA)法和比较分子相似性指数分析(comparative molecular similarity index analysis,CoMSIA)法进行3D-QSAR模型的构建,基于3D-QSAR模型分析同一骨架取代基的变化带给化合物的活性变化,预测不同力场对化合物活性的影响,并对设计的衍生化合物进行活性预测分析。结果表明,经CoMFA法和CoMSIA法构建的3D-QSAR模型可信度高(交叉验证系数q2分别为0.728和0.563),且有良好的活性预测能力(非交叉验证系数r2分别为0.954和0.981)。基于该模型得到的化合物预测活性与实际活性残差较小且存在良好的线性关系,进一步证明所得3D-QSAR模型的可靠性。通过分析3D-QSAR模型的力场分布,推测在R1基团处引入位阻较大的疏水性基团、在R2基团苯环的邻位引入同时具有负电性和疏水性但不含卤素原子的基团、用负电性的大位阻基团取代R基团等均可提高N-氯磺基-N-甲基氨基甲酸酯的活性。基于此设计的20种衍生化合物的活性变化从正反两方面印证了该推测的合理性。研究成果可用于指导兼具苯甲酰基脲类和氨基甲酸酯类杀虫剂作用机制的N-氯磺基-N-甲基氨基甲酸酯衍生物的设计。  相似文献   

11.
BACKGROUND: For the last 15 years the agrochemical industry has focused on using genetic modification to put genes that confer resistance to existing commercial herbicides into crop plants rather than on discovering new herbicides with novel modes of action. The widespread appearance of weeds resistant to those herbicides is now causing the industry to revive their herbicide discovery programs. RESULTS: Elucidation of quantitative structure–activity relationships (QSARs) played a major role in the discovery and development of existing commercial herbicides, but the advent of genetically modified crops has caused published work (at least) in the area to drift from the industrial arena into academic studies. The focus has also turned inward, to refining models for established herbicide targets instead of elucidating new ones. CONCLUSION: This perspective highlights the importance of QSARs and quantitative structure–property relationships (QSPRs) to herbicide discovery in an historical context and provides some guidance as to how they might profitably be applied going forward. Copyright © 2011 Society of Chemical Industry  相似文献   

12.
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   

13.
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   

14.
The quantitative relationship between the structure of 2-(arylimino) thiazolidines (AITs), arylethanolamines (AEAs) and 2-(arylalkylamino)-2-thi-azolines (AATs) and their octopamine (OA)-agonist activities against the ventral nerve cord of American cockroach, Periplaneta americana L., was analysed using reported physicochemical parameters and regression analysis. The electronic nature of a substituent was the most important factor for AAT, followed by the hydrophobic effects: the more electron-donating and the more hydrophobic the substituent, the greater the activity. The hydrophobic nature of a substituent in AEA was the most important factor, followed by the steric effects: the more hydrophobic the substituent, the greater the activity. The more electron-donating the substituent of AIT, the greater the activity.  相似文献   

15.
郇志博  于世幸 《植物保护》2024,50(3):195-202
豇豆农药残留问题非常严峻, 对豇豆上普通大蓟马的化学防治是造成豇豆农残超标的主要原因, 开展普通大蓟马的绿色防治迫在眉睫。利用植物挥发物驱避害虫是一种重要的害虫绿色防控手段。本研究利用GC-MS分析了胡椒和肉桂的挥发性化合物组成, 并利用“Y”形嗅觉仪测定了胡椒和肉桂及5种主要挥发物对普通大蓟马的驱避作用。结果表明, 在胡椒中鉴定出27种挥发性成分, 主要成分为β-石竹烯, 含量占43.1%; 在肉桂中鉴定出21种挥发性成分, 主要成分为肉桂醛(28.4%)、α-可巴烯(15.4%)、α-依兰油烯(14.1%)、γ-杜松烯(14.9%)。行为反应测定结果表明胡椒和肉桂对普通大蓟马分别具有极显著和显著的驱避作用; β-石竹烯、肉桂醛、α-可巴烯浓度为10%和1%时对普通大蓟马具有极显著的驱避作用, 10%的α-依兰油烯和10%的γ-杜松烯对普通大蓟马分别具有极显著和显著的驱避作用。本研究对豇豆普通大蓟马绿色防控技术研发和驱避剂的开发具有一定指导意义。  相似文献   

16.
17.
BACKGROUND: Monoterpenoids are a large group of plant secondary metabolites. Many of these naturally occurring compounds have shown good insecticidal potency on pest insects. Previous studies in this laboratory have indicated that some monoterpenoids have positive modulatory effects on insect GABA receptors. In this study, the key properties of monoterpenoids involved in monoterpenoid binding activity at the housefly GABA receptor were determined by developing quantitative structure‐activity relationship (QSAR) models, and the relationship between the toxicities of these monoterpenoids and their GABA receptor binding activities was evaluated. RESULTS: Two QSAR models were determined for nine monoterpenoids showing significant effects on [3H]‐TBOB binding and for nine p‐menthane analogs with at least one oxygen atom attached to the ring. The Mulliken charges on certain carbon atoms, the log P value and the total energy showed significant relationships with binding activities to the housefly GABA receptor in these two QSAR models. CONCLUSIONS: From the QSAR models, some chemical and structural parameters, including the electronic properties, hydrophobicity and stability of monoterpenoid molecules, were suggested to be strongly involved in binding activities to the housefly GABA receptor. These findings will help to understand the mode of action of these natural insecticides, and provide guidance to predict more monoterpenoid insecticides. Copyright © 2012 Society of Chemical Industry  相似文献   

18.
BACKGROUND: Culex pipiens molestus Forskal has been reported as a dominant species in underground structures of urban areas in the Republic of Korea (ROK) during all seasons and becomes bothersome to humans in late autumn and winter. Most Cx. pipiens molestus in septic tanks are controlled in the ROK using larvicides such as Bt and IGR. However, there are a number of problems associated with larvicides, such as high cost and requirement for frequent use. In the present work, a new control method for Cx. pipiens molestus in septic tanks by using mixtures of sucrose solution with insecticides was investigated. RESULTS: The insecticidal and repellent activities of ten insecticides were evaluated for best control of Cx. pipiens molestus in septic tanks. Firstly, differences in susceptibilities to insecticides were evaluated in topical assays by forced direct contact bioassay and in a screened wire cage by free direct contact bioassay. The difference in insecticide susceptibility in the mosquitoes was the result of repellency by the insecticides. In three septic tanks, the density of Culex mosquitoes was sharply reduced by a deltamethrin–sucrose solution kit. CONCLUSIONS: The results demonstrated the potential for mosquito control by deltamethrin–sucrose solution, and the study offers basic information related to mosquito control in septic tanks. Copyright © 2011 Society of Chemical Industry  相似文献   

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