新化合物天维菌素的杀虫杀螨活性

为明确天维菌素(tenvermectin)的杀虫杀螨活性,分别测定了其对小菜蛾Plutellaxylostella (药膜法)、粘虫Mythimna separate Walker (小叶碟添加法)、棉铃虫Helicoverpaarmigera Hübner (饲料混药法)、松材线虫Bursaphelenchus xylophilus (浸渍法)和朱砂叶螨Tetranychus cinnabarinus (叶片浸渍法和玻片浸渍法)的室内毒力,并采用叶碟喷雾法测定了其对朱砂叶螨的盆栽药效。结果表明:天维菌素对鳞翅目害虫小菜蛾、粘虫和棉铃虫的LC50值分别为22.21、19.66和22.09 mg/L,对松材线虫的LC50值为1.94 mg/L,毒力显著高于米尔贝霉素(P50值分别为0.0051和0.0089 mg/L。盆栽试验结果表明:0.2 mg/L的天维菌素药后5 d对朱砂叶螨的防效最高,达97.42%;药后7 d,尽管天维菌素与阿维菌素的防治效果均有所下降,但天维菌素不同浓度(0.0125~0.2 mg/L)处理防效仍保持在80.23%~91.96%之间。研究表明,天维菌素对供试的有害生物均具有较高活性,具有研究开发潜力。     

大环内酯类新化合物天维菌素杀螨活性及田间防治效果

为明确新化合物天维菌素的杀螨活性,采用叶碟喷雾法测定了在室内天维菌素对朱砂叶螨Tetranychus cinnabarinus、柑橘红蜘蛛Panonychus citri及二斑叶螨Tetranychus urticae的毒力,并研究了其制剂对螨类害虫的田间防治效果。结果表明,天维菌素对朱砂叶螨若螨和雌成螨均具有较高的毒力,其LC50分别为0.011、0.11 mg(a.i.)/L,杀螨活性优于弥拜霉素、阿维菌素,但杀卵活性较差。田间试验中2%天维菌素微乳剂具有良好的速效性且具有一定的持效期,在有效成分8~40 mg/kg剂量下,对朱砂叶螨和二斑叶螨药剂处理14 d的防治效果分别为83.22%~92.77%和85.49%~92.64%,有效控制期在14 d以上;在有效成分75 mg/kg剂量下,对柑橘红蜘蛛防治效果最好,处理1、3、7、14 d的防治效果分别达96.53%、97.72%、98.05%和91.42%。表明天维菌素具有作为杀螨剂的潜力。     

姜黄素嘧啶酮衍生物的合成及杀螨活性

在明确姜黄素具有杀螨活性,且其结构中的双羰基并非是起杀螨作用的关键基团的基础上,设计、合成了4个新颖的姜黄素嘧啶酮衍生物,其结构经红外光谱、核磁共振氢谱和质谱分析确认。生物活性测定结果表明:4个目标化合物均表现出优于母体化合物姜黄素的杀螨活性,处理48 h后,活性最好的4,6-二 -2-嘧啶酮(3a)对朱砂叶螨Tetranychus cinnabarinus和柑橘全爪螨Panoychus cotri的LC50值分别为487.5和200.3 mg/L,其毒力约为姜黄素的4倍;而处理72 h后,化合物 3a 对朱砂叶螨的LC50值为40.7 mg/L,其毒力约为姜黄素的14倍。     

米尔贝霉素类似物的合成及杀螨杀蚜活性

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。     

含酰肼结构阿维菌素衍生物的合成及生物活性

为减少能源消耗和环境污染,提高阿维菌素B2的实际应用价值,将阿维菌素B2a的23-OH氧化成羰基后分别与吡啶甲酰肼、苯磺酰肼、溴代苯甲酰肼以及肼基甲酸甲酯等反应,设计合成了6个新的酰肼类阿维菌素B2a衍生物,采用高分辨质谱(HRMS)、核磁共振氢谱(1H NMR)等对新化合物的结构进行表征,并初步测试了其对小菜蛾、蚜虫...     

姜黄素异噁唑和吡唑衍生物的合成及杀螨活性

为了寻求和开发新的基于天然产物的杀螨剂,在明确姜黄素具有杀螨活性,且其结构中的双羰基并非杀螨活性关键基团的基础上,设计并合成了15个姜黄素异噁唑和吡唑衍生物,其结构均经红外光谱、核磁共振氢谱和质谱分析确认。生物活性测定结果表明:几乎所有的目标化合物对朱砂叶螨Tetranychus cinnabarinus和柑橘全爪螨Panonychus citri均表现出了比先导化合物姜黄素更优异的触杀活性,其中化合物 4和11 的活性最为突出。处理48 h后,化合物 4 对朱砂叶螨和柑橘全爪螨的LC50值分别为333.0和156.0 mg/L,其毒力是姜黄素的6.35和4.56倍, 11 的LC50值分别为478.4和144.7 mg/L,毒力是姜黄素的4.42和4.92倍;相应地处理72 h后, 4 的LC50值分别为115.0和84.9 mg/L,其毒力是姜黄素的5.02和1.43倍, 11 的LC50值分别为91.0和68.7 mg/L,毒力是姜黄素的6.35和1.77倍。化合物 4和11 可作为进一步开发研究的具有杀螨活性的候选化合物。     

新农抗天山菌素的杀虫抑菌活性

天山菌素（tianshanmysin）是从链霉菌GAAS7310 Streptomyces sp．的发酵菌丝中分离提取出来的一种活性成分。为了确定该抗生素的应用范围和应用方法，在室内测定了它对卫生害虫家蝇和田间常见的12种植物病原真菌的生物活性。结果表明，天山菌素对家蝇Muscadomestica具有很高的毒杀活性，死亡中浓度（Lc50）为0．6μg／mL；对甘薯软腐病病菌Rhizopus nigrtcans Ehrb、炭疽病病菌Colletotrichum nigrum EL．et Halst和玉米弯孢菌叶斑病病菌Curvularia lunata（Wakker）Boed3种病原真菌有较显著的抑制作用，抑制中浓度（IC50）分别为70．66、114．95和47．17μg／mL。因此GAAS7310是一株值得进一步研究的农用抗生素生产菌株，具有潜在的开发价值。     

吡啶联三唑类衍生物的合成及杀虫活性

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。     

嘧啶酮类衍生物的合成及杀虫活性

为了创制高效广谱的绿色杀虫剂,以(E)-4,5-二氢-6-甲基-4-(3-吡啶亚甲基氨基)-1,2,4-三嗪-3(2H)-酮(吡蚜酮)为先导,用带有不同电荷密度的五元、六元取代苯环或杂环取代其结构中的吡啶环部分,合成了10个全新的嘧啶酮类衍生物,特别对其中所包含的三嗪环和二氢喹唑啉酮合成部分进行了重点研究。所有目标化合物的结构均经过核磁共振氢谱、高分辨质谱及红外光谱的确认。初步杀虫活性测试结果表明,目标化合物对蚜虫Aphis craccivora未表现出明显的杀虫活性,初步暗示了先导化合物吡蚜酮结构中所含的吡啶环部分可能对其杀虫活性起了重要作用。     

松油烯-4-醇酯类衍生物的合成及杀虫活性

松油烯-4-醇具有较高的生物活性,在前期研究基础上,以松油烯-4-醇为原料,对其羟基进行改造,合成了12个松油烯-4-醇酯类衍生物 Z1~Z12,其中Z3、Z4、Z8、Z9、Z10、Z11、Z12为新化合物。所有化合物的结构均经核磁共振氢谱、碳谱及质谱确证。初步杀虫活性测定结果表明:各化合物对粘虫均有一定的触杀作用,其中Z5 活性最高,其LD50值为0.072 8 mg/头,为松油烯-4-醇的1.32倍;除 Z9 外,其余11个化合物对家蝇均具有一定的熏蒸作用,但其毒力均低于松油烯-4-醇。     

Design,synthesis and acaricidal activity of novel strobilurin derivatives containing pyrimidine moieties

BACKGROUND: The intermediate derivatisation method based on bioisosteric replacement led to the discovery of the lead strobilurin compound 5a. To produce new strobilurin analogues with improved activity, a series of substituted pyrimidines were synthesised and bioassayed. RESULTS: The compounds were identified by ¹H NMR, IR, MS and elemental analysis. The highly active compound 5g was studied by X‐ray diffraction. Preliminary bioassays demonstrated that some of the title compounds exhibited excellent acaricidal activity against Tetranychus cinnabarinus (Boisd.) at 10 mg L^?1. The relationship between structure and acaricidal activity is reported. CONCLUSION: The present work demonstrates that strobilurin derivatives containing pyrimidine moieties can be used as possible lead compounds for developing novel acaricides. Copyright © 2010 Society of Chemical Industry     

Design, synthesis and insecticidal activities of novel pyrazole amides containing hydrazone substructures

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     

Synthesis and acaricidal activity of phenylpiperazine derivatives

We synthesized 33 new phenylpiperazine derivatives and assessed their acaricidal activity. These derivatives were synthesized through sequential reactions consisting of the sulfonylation of 2-substituted 4-methylaniline with chlorosulfonic acid, reduction with red phosphorus and iodine, alkylation by alkyl halide, cyclization with bis(2-chloroethyl)amine hydrochloride, and N-substitution reaction of phenylpiperazines with various reagents. All phenylpiperazines synthesized were evaluated for acaricidal activity and their structure–activity relationships discussed, it was found that 4-substituted 1-[2-fluoro-4-methyl-5-(2,2,2-trifluoroethylsulfanyl)phenyl]piperazine derivatives exhibited good acaricidal activity. Among them, 1-[2-fluoro-4-methyl-5-(2,2,2-trifluoroethylsulfanyl)phenyl]-4-(trifluoromethylsulfonyl) piperazine showed the highest level of activity against Tetranychus urticae and provided a high level of activity against Tetranychus kanzawai and Panonychus citri. In addition, studies on the effect at various stages of T. urticae exhibited that this compound showed good activity against both adults and eggs.     

Synthesis and insecticidal activity of 5-acyloxyimino-5-deoxyavermectin B1 derivatives

Four novel 5-acyloxyimino-5-deoxyavermectin B1 compounds have been synthesized from avermectin B1 by selective oxidization of the hydroxy group at C-5, followed by oximation and convenient esterification. Their structures were confirmed by IR, 1H NMR, 13C NMR and MS. Insecticidal activities of the intermediate oxime and the four new acyl derivatives were evaluated against Helicoverpa armigera, Spodoptera exigua and Musca domestica.     

Design,synthesis and biological activities of new strobilurin derivatives containing substituted pyrazoles

BACKGROUND: Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin analogues with high activity, a series of new strobilurin derivatives containing substituted pyrazoles in the side chain were synthesised and bioassayed. RESULTS: The compounds were identified by ¹H NMR, IR, MS and elemental analysis. Preliminary bioassays indicated that some title compounds exhibited excellent fungicidal activities against Pseudoperonospora cubensis (Burk. & Curt.) Rostovsev and Erysiphe graminis DC f. sp. tritici Marchal, protecting cucumber and wheat at 6.25 and 1.56 mg L^?1 respectively, and showed a moderately high acaricidal activity against Tetranychus cinnabarinus (Boisd.) at 20 mg L^?1. The relationship between structure and biological activity is discussed in terms of effects of the substituent of the pyrazole ring. CONCLUSION: The present work demonstrates that strobilurin analogues with substituted phenylpyrazolylmethoxymethyl side chains can be used as possible lead compounds for further developing novel fungicides and acaricides. Copyright © 2009 Society of Chemical Industry