含吡唑甲酰胺基E-β-法尼烯类似物的设计、合成及生物活性

为发现防治蚜虫的新型活性化合物,以蚜虫报警信息素E-β法尼烯(EBF)为先导,设计合成了20个未见文献报道的含吡唑环甲酰胺基EBF类似物,所有化合物结构均通过1H NMR,IR及HRMS确证.初步生物活性研究表明,部分目标化合物对五日龄豆蚜(Aphis craccivora Koch)在600mg/L时表现出较好的杀虫活性,其中5a及5k对豆蚜活性与商品化药剂氟虫腈及先导化合物EBF相当,甚至优于EBF.对影响目标化合物的活性因素进行了初步探讨.     

新型双环新烟碱类似物的合成及其生物活性

设计合成了六个新型双环新烟碱类似物,通过1H NMR,13C NMR,高分辨质谱和单晶结构对目标化合物的结构进行了表征.初步的生物活性测试表明:在500 mg?L-1浓度下,目标化合物6a,6c~6f对豆蚜(Aphis craccivora)具有很好的杀虫活性.通过分子对接比较并解释了目标化合物6a和吡虫啉的活性和作用模式的差异,其结果表明目标化合物6a的吡啶环和受体残基色氨酸147的芳香环侧链具有?-?堆积作用,与吡虫啉的作用方式存在一定差异.     

3-芳基异噁唑啉-吡唑-5-甲酰胺类化合物的合成及杀虫活性研究

以5,5-二甲氧基-2,4-二氧代戊酸乙酯为原料,设计合成了一系列含芳基异噁唑啉结构的吡唑-5-甲酰胺类化合物,产物结构经~1HNMR, ~(13)CNMR和HRMS确认.初步杀虫活性测试表明,多数化合物在500mg/L浓度下对粘虫(Mythimna separate)有着较高的活性(致死率≥80%),在100 mg/L的浓度下,有三种化合物对粘虫仍有中等程度的活性(致死率≥60%).在500 mg/L时,有四种化合物对苜蓿蚜(Aphis craccivora)也有较好的活性(致死率≥80%).因此,对该类化合物的结构优化可作为寻求新型杀虫剂而进行深入研究.     

芳亚甲基硝基缩氨基胍类化合物的合成及杀虫活性

依据活性亚结构拼接原理, 以硝基胍为原料, 合成了一系列具有新烟碱类和缩氨基脲类杀虫剂共同结构特征的芳亚甲基硝基缩氨基胍类化合物, 其结构通过¹H NMR、 IR和元素分析等方法进行了确证. 杀虫活性测定结果表明, 在600 μg/mL浓度下, 目标化合物对桃蚜[Myzuspersicae(Sulzer)]具有较优异的活性, 其中化合物4-2, 4-8, 4-10, 4-16, 4-27, 4-31和4-34的校正死亡率均在90%以上. 进一步以桃蚜、 棉蚜(Aphis gossypii)和桃粉蚜(Hyalopterusamygdali blanchard)为对象, 测定了化合物4-2, 4-8和4-34的精密毒力. 结果表明, 它们在低浓度下仍然具有很高的活性, 其中化合物4-8对棉蚜的活性甚至优于对照药剂吡虫啉, 在3.13 μg/mL浓度下致死率仍高达95.7%(吡虫啉为79.4%), 具有进一步研究开发的价值.     

N'-{1-[(6-氯吡啶-3-基)甲基]-5-甲基-1H-1,2,3-三唑-4-甲酰基}-N'-叔丁基-N-取代苯甲酰肼的合成与杀虫活性

双酰肼化合物作为一类重要的昆虫生长调节剂,已广泛应用于农作物的保护中.为了发现新颖结构的高效、低毒双酰肼杀虫剂先导化合物,采用点击化学常用的1,2,3-三唑杂环将新烟碱杀虫剂的药效团2-氯-5-(氯甲基)吡啶引入到双酰肼分子骨架中,设计并合成了9种未见文献报道的含双杂环结构的双酰肼目标化合物,其结构经IR,1HNMR,ESI-MS和元素分析测试技术确证.初步的生物活性测定结果表明,部分目标化合物在200mg/L质量浓度下对小菜蛾(Spodoptera exigua)和甜菜夜蛾(Plutella xylostella)表现出中等程度的杀虫活性;但所有目标化合物在200mg/L浓度下对蚕豆蚜虫(Aphis fabae)的杀虫活性均较弱..     

新型呋喃α-丁烯内酯类化合物的设计、合成及其生物活性研究

近年来,新烟碱杀虫剂的广泛使用不但导致害虫对其抗性逐渐增强,而且其对蜜蜂的毒性影响也越来越受到关注,因此设计合成生态友好型的新烟碱杀虫剂替代品显得迫在眉睫.实验室前期以低蜂毒杀虫剂氟吡呋喃酮的丁烯内酯为骨架,基于骨架相似性搜索发现,新型呋喃α-丁烯内酯骨架具有一定杀蚜活性.基于烟碱乙酰胆碱受体蛋白特征融合经验方法,设计并合成了一系列新型呋喃α-丁烯内酯类化合物.在500μg/m L浓度下对目标化合物进行大豆蚜和桃蚜的杀虫活性测试,结果表明该系列化合物对大豆蚜和桃蚜均表现一定的致死活性,其中(E)-3-((5-(3-氯苯基)呋喃-2-基)亚甲基)-5-甲基呋喃-2(3H)-酮(7bh)和(E)-3-((5-乙基呋喃-2-基)亚甲基)-5-(对甲苯基)呋喃-2(3H)-酮(7ch)对大豆蚜和桃蚜的致死率均达到70%以上,并且7bh对大豆蚜(LC₅₀=70.83μg/mL)和桃蚜(LC₅₀=71.96μg/mL)的杀虫活性与吡蚜酮在同一个数量级.意外发现该类化合物在50μg/m L浓度下对水稻纹枯病菌也表现出一定的离体抑菌活性.分子对接研究推测可能...     

新型含氯代噻唑基团和嘧啶环的吡唑肟醚类衍生物的合成及其生物活性研究

为解决抗性问题,寻找新的活性化合物,在前期工作基础上,运用生物等排原理,以吡唑肟醚为骨架,引入了第二代新烟碱类重要药效团氯代噻唑和另一重要基团嘧啶环,设计合成了系列新型吡唑肟醚类化合物.以1H NMR,IR,元素分析及MS进行结构确证,并进行了杀虫、杀螨及杀菌活性测定.部分具有氯代噻唑环的A系列化合物显示了良好的杀蚊虫活性(100%,5 mg·L-1)、杀豆蚜活性(100%,200 mg/L)和杀螨活性(100%,200 mg/L);具有嘧啶环的B系列化合物显示了一定的杀菌活性.     

弥拜霉素类似物的合成、表征和杀虫活性研究

以弥拜霉素类似物依维菌素为原料,根据类同合成法和亚结构连接法原理,对依维菌素进行脱糖,再与相应的酰氯进行酯化、肟化反应制得两个系列弥拜霉素类似物化合物4Ia～5IId,所有目标化合物都通过核磁共振氢谱、高分辨质谱的确认,并分别对朱砂叶螨(Tetranychus cinnabarinus)、南方粘虫(Mythimna sepatara)和蚕豆蚜(Aphis fabae)进行室内杀虫活性测定,结果表明所有衍生物均表现出不同程度的杀虫活性,其中化合物4IIa和4IIb对粘虫和蚜虫表现出很高的杀虫活性.     

新型杂环查尔酮衍生物的合成及其杀虫活性研究

以含杂环的醛和氨基苯乙酮以及酰氯为原料,通过Claisen-Schmidt缩合反应和酰氯的氨解反应合成了21个新的杂环查尔酮衍生物.以蚕豆蚜(Aphis craccivora)和菜青虫(Pieris rapae)为靶标,对合成化合物的杀虫活性进行了实验室生测.结果显示,大部分化合物都对这两种害虫有一定的毒杀活性.其中,化合物2l对蚕豆蚜的半致死浓度(LC_(50))为1.6μg/m L,毒杀效果优于吡虫啉(LC_(50)为1.8μg/m L),1b、1f、2j、2n对蚕豆蚜的毒杀效果也和吡虫啉接近;化合物1f和2m对菜青虫的LC_(50)分别为6.6μg/m L和8.5μg/m L,毒杀效果比高效氯氰菊酯(LC50为9.2μg/m L)更好.     

含亚胺基(E)-β-Farnesene类似物的设计、合成及生物活性研究

为了发现控制蚜虫的新型高活性化合物,以蚜虫报警信息素(E)-β-farnesene(EBF)为先导,引入不同类型的芳香环(叔丁基)替代EBF结构中不稳定的共轭双键,设计了一系列含亚胺基EBF类似物.采用N-烷基化反应和还原胺化反应两种路线合成了19个目标化合物.所有化合物结构均通过~1HNMR、~(13)CNMR、IR及HRMS确证.对目标物进行了生物活性测试并探讨了结构活性关系,结果表明:含苯环或吡啶环的化合物对桃蚜具有较好的驱避活性,其中以3g、3l和3m最为显著,驱避率分别为62.0%、62.5%和64.6%;含1,3,4-噻二唑等杂环的化合物对桃蚜具有一定的杀虫活性,在200μg/m L浓度下化合物3i、3l、3r和3s的致死率分别为70.7%、72.6%、70.4%和75.5%,显著高于先导EBF;而含叔丁基的非环EBF类似物的驱避和杀蚜活性均不明显.     

Synthesis,insecticidal activity and stability study of novel nitromethylene neonicotinoids with five-membered aromatic heterocycles

Twenty-four novel neonicotinoid analogues with nitromethylene and five-membered aromatic heterocycles were designed and synthesized. All target molecular structures have been confirmed by analytical and spectral data. Some compounds exhibited notable insecticidal activities against aphid (Aphis medicaginis) and brown planthopper (Nilaparvata lugens). The aqueous stability test confirmed that the stabilities of those compounds were superior to the leading compound, and the photostability was even better than that of imidacloprid.     

Synthesis of 1,3-dithiolane-containing nitromethene compounds and their biological activity as insecticides

1,3-Dithiolane-containing nitromethylene derivatives, as candidates for screening as neonicotinoid insecticides, were synthesized by reaction of compound (4) with 1,2-ethanedithiol. Compounds 7a–g were obtained via Mannich reaction of (E)-1-((1,3-dithiolan-2-yl)methyl)-2-(nitromethylene)imidazolidine (6), primary amines and formaldehyde. The synthesized compounds were identified by ¹H NMR, IR spectroscopy and elemental analysis. Preliminary bioassays indicated that most of the compounds had moderate insecticidal activity against Aphis craccivora. The relationship between molecular structure and biological activity is discussed.     

Facile three-component synthesis and insecticidal evaluation of hexahydroimidazo[1,2-a]pyridine derivatives

A series of new hexahydroimidazo[1,2-α]pyridine derivatives were synthesized via convenient and practical three-component reactions.Preliminary bioassays showed that majority of the target compounds exhibited moderate to excellent insecticidal activity against cowpea aphids(Aphis craccivora).Among them,compound 91 demonstrated significant activity with LC_(50) value of0.00918 mmol/L which was about 3.8-fold higher than that of imidacloprid(IMI).Furthermore,the study of stereostructure-activity relationship of four isomers of 9k indicated that configuration played a key role in insecticidal activity of these compounds.     

Synthesis and Insecticidal Activities of Chlorothiazolyl Analogs of Nitromethylene Neonicotinoids with Tetrahydropyridine Fixed cis‐Configuration

The chlorothiazolyl moiety was an effective bioisoster of chloropyridyl in pesticide molecular design. Replacement of chloropyridyl in cis‐nitromethylene neonicotinoids with chlorothiazolyl generated the chlorothiazolyl counterpart of nitromethylene neonicotinoids with tetrahydropyridine fixed cis‐configuration. Bioassay against cowpea aphis (Aphis craccivora) indicated that the chlorothiazolyl analogs could maintain the high insecticidal activity.     

Synthesis and Characterization of Imidacloprid/Hydrotalcite-like Compound Nanohybrids

Hydrotalcite‐like compounds (HTlc) were first modified by sodium dodecyl sulfate (SDS), then the intercalation of imidacloprid (IM) into modified HTlc was carried out in mixed solvent of toluene/ethanol by an evaporating solvent enhanced intercalation method, obtaining IM‐SDS‐HTlc nanohybrids. It was found that the nanohybrids could well control the release of imidacloprid, demonstrating that the nanohybrids are a potential pesticide controlled‐release formulation. The release of imidacloprid from IM‐SDS‐HTlc nanohybrids is dependent on the pH and the presence of electrolyte in release medium. Acidic medium and the presence of electrolytes induce the higher release rate of imidacloprid. The release process of imidacloprid from IM‐SDS‐HTlc nanohybrids can be described by pseudo‐second‐order release kinetics.     

Nitroylides 6. Transfer of a nitromethylene fragment with the aid of iodonium nitroylides

Conclusions The ability of iodonium nitroylides to transfer a nitromethylene fragment to compounds containing a heteroatom with a lone pair has been demonstrated in the example of reactions with dimethyl sulfide, pyridine, and thiourea, making it possible to obtain various types of nitroylides, including the heretofore unknown pyridinium and diaminomethylenesulfonium dinitroylides.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2355–2360, October, 1978.For the preliminary data, see [1].     

[反]-β-法尼烯类似物的设计、合成与生物活性研究

对[反]-β-法尼烯(EBF)类似物的骨架结构原子进行改造,引入吡虫啉系列活性基团,设计合成了13个结构新颖的EBF类似物,并对其生物活性进行了研究.结果表明,这些化合物对蚜虫具有明显的抑制活性,尤其在低浓度时活性更明显,如质量浓度为25mg/L时,I₁₀和I₁₃对蚜虫的抑制率分别为93.1%和87.1%,远高于同浓度下吡虫啉的抑制率(66.7%).     

Intramolecular Cyclization of 1-(ω-Phenylalkyl)-2-(nitromethylene)pyrrolidines in Triflic Acid

1-(ω-Phenylalkyl)-2-(nitromethylene)pyrrolidines in triflic acid undergo a C,O-diprotonation, followed by loss of water, to form conjugated iminium–hydroxynitrilium dications, which react with the tethered phenyl ring by electrophilic aromatic substitution to afford tricyclic iminium compounds as triflate salts. The scope and mechanism of this reaction are discussed.     

Synthesis and insecticidal activities of novel bridged-neonicotinoids

A series of novel bridged-neonicotinoid analogues were designed and synthesized, which were constructed by starting material 8 with cyclopentenone or cyclohexenone in the presence of catalyst aluminium chloride. All of the compounds were characterized and confirmed by ¹H NMR, ¹³C NMR, HRMS and IR. The bioassay tests showed that compounds 5 and 6a showed higher bioactivities than imidacloprid against Aphis craccivora.