5-吡唑羧酸酰胺先导结构的创新与优化及其杀菌作用机制研究

In this project, novel carboxamides, especially 1H-pyrazole-5-carboxamides will be designed and synthesized by selection self-designed and synthesized with insecticidal and fungicidal activities A439 and A450 containing multiple common important groups in pesticide molecules such as pyrazole, thiazole and amide as lead molecules by application of bioisostere, intermediate derivatization, active groups combination, according to the relevant QSAR model. The bioassay and structure-activity relationship of the synthesized compounds will be studied. The efficacy of 2 to 3 compounds with high fungicidal activities will be verified in the field. The candidate fungicide with further development prospects will be put forward based on the field efficacy, control spectrum and cost etc. Based on A439 with good efficacy against Botrytis cinerea in green house, but with low inhibition activity on the mycelial growth, in order to clarify whether A439 and the candidate fungicide are commercialized 1H-pyrazole-4-carboxamides SDHIs or plant activators, the mechanism of action of A439 and the candidate fungicide will be studied by docking; hinder the electron transfer activity test, spore impact test and microstructure observation. It is hope to find specific targerts which will provide important scientific basis for the discovery of carboxamide new leads as well as new mode of action.

本项目选择自主设计并合成集吡唑、噻唑和酰胺等多个农药分子中常见重要基团于一体并具有杀虫和杀菌活性的5-吡唑羧酸酰胺新分子A439和A450为先导，结合相关构效关系模型，运用生物电子等排、活性基团拼接、中间体衍生化等原理设计并合成羧酸酰胺，特别是吡唑羧酸酰胺新分子，并对其进行系统的生物活性和构效关系研究；对高杀菌化合物进行田间小区药效验证试验；基于防治谱、防治效果和成本等提出具有开发价值的侯选杀菌剂；根据A439对黄瓜灰霉病防治效果好，但对其菌丝生长抑制活性不明显的活性特点，利用对接实验技术和电子传递阻碍活性测试、孢子影响测试、显微形态观测等方法，对A439和候选杀菌剂杀菌机制进行研究，初步明确其杀菌机制与已商品化的4-吡唑羧酸酰胺琥珀酸脱氢酶抑制剂类杀菌剂是否异同、是否植物诱导抗病激活剂，期望发现特异性靶标，为羧酸酰胺新先导和新作用机制发现提供重要科学依据。

在前期自主设计合成兼具杀虫和杀菌活性的5-吡唑羧酸酰胺分子A439和A450的基础上，运用电子等排、活性基团拼接、中间体衍生等原理，设计合成6类311个具潜在生物活性结构多样性酰胺类化合物。按国家农药创制工程技术研究中心活性测试SOP对化合物进行了8个靶标杀菌、3个靶标杀虫/螨和6个靶标除草生物活性普筛，对普筛A级杀菌和杀虫活性化合物进行了初筛，基于初筛，对相关化合物进行了复筛，对有进一步研发价值的化合物进行了田间试验和工艺、制剂、毒性、机理等研究。筛选结果表明：化合物具有杀菌和杀虫广谱活性、无明显除草活性；基于研究结果，提出杀菌化合物A439具有进一步优化价值、A095具有进一步优化与进一步研究与开发价值，杀虫化合物A038具有进一步研究与开发价值。对所合成化合物进行了构效关系研究，总结出一些对新农药创制具有借鉴和指导作用的规律；选择A095为探针分子，通过活性测定、对水稻纹枯病原菌丝体内含物渗漏影响等研究，初步探究了A095的杀菌机制；通过本项目研究，在国内、外学术期刊和学术会议发表论文18篇，7篇被SCI收录；申请中国发明专利4项、PCT专利1项，授权中国发明专利6项；培养博士2名和硕士6名。