新型CYP51和SDH双靶点酰胺类杀菌剂的设计合成及构效关系研究

In research and discovery of new pesticides, studies of the interaction between biological active molecule and target enzyme are key to obtain highly active inhibitors. Targeting CYP51 (sterol 14α-demethylase) and SDH (succinate dehydrogenase) of the crop fungus, and on the basis of our previous results of multifunctional pharmacophore which interacts with CYP51 and SDH, we design novel aminoamides and alkyloxyamides as CYP51 and SDH dual-targets fungicides. The synthesis of these compounds will also be investigated. Active compounds will be obtained by evaluation of the enzyme inhibition activity of the mentioned compounds against the CYP51 and SDH, and their fungicidal activity. Extensive studies on the interaction mechanism between the obtained biological active compound and CYP51 and SDH, structure-activity relationship and structure optimization of the active compound will be carried out by rational combination of homology modeling, molecular docking, 3D-QSAR and experiment technology, to reveal the interaction law between the active compound and CYP51 and SDH. Novel inhibitors or lead compounds of amides with high activity against CYP51 and SDH will be possibly obtained through few cycles of design, synthesis, activity assay, structure-activity relationship research and structure optimization. The results of the project will provide a new method to design dual-targets pesticides, and also provide important experimental and theoretical basis for molecule design of new pesticides based on the ligand and receptor.

在新农药创制中，活性化合物与靶酶之间相互作用的研究是获得高活性抑制剂的关键。本项目以农作物真菌CYP51（甾醇14α-去甲基化酶）和SDH（琥珀酸脱氢酶）为双靶酶，基于我们前期发现的与CYP51和SDH酶都能作用的多功能药效团，拟设计合成结构新颖的CYP51和SDH双靶点杀菌剂：氨基酰胺类和烃氧基酰胺类化合物。通过杀菌活性及对酶抑制活性的测定筛选出活性化合物。利用同源模建法、分子对接法、三维定量构效关系研究等分析手段和实验技术的有机结合开展活性化合物与CYP51和SDH双靶酶的作用机理、构效关系和结构优化的研究，揭示活性化合物与靶酶相互作用的规律。经过设计－合成－活性评价－构效关系研究－结构优化的多次循环，力争获得高活性的新型CYP51和SDH双靶点杀菌剂或先导化合物。为双靶点农药的分子设计提供新方法，为基于配体-受体相互作用的农药分子设计策略提供重要的实验基础和理论依据。

通过大量系统的研究工作，本项目已基本完成研究计划工作，取得了较好的成果。设计合成了380余个目标化合物和相关化合物，着重研究了它们的合成，进行了结构表征；测定了所合成化合物的抑菌活性。测定了部分活性化合物对有关CYP51、SDH酶的抑制活性。采用同源模建法构建了稻瘟病菌CYP51的三维结构，利用分子对接法对活性化合物与稻瘟病菌CYP51和SDH的相互作用机理进行了研究，较为系统地探索了活性化合物的构效关系，进行结构优化。通过本项目的研究获得了重要结果：①获得了27个高抑菌活性（>90%）的化合物，其中12化合物的抑菌活性为100%，具有潜在的应用前景，有些可作为后续相关研究的先导化合物。②作为CYP51酶抑制剂的特点应在活性位点可与卟啉环，或有关氨基酸残基形成氢键等作用；作为SDH酶抑制剂的特点应在活性位点可与酶的氨基酸残基Tyr58、Try173、Arg43、His42、Hem143中的一个或几个形成氢键作用等。作为CYP51和SDH双靶点抑制剂，分子骨架应进入酶活性空腔，并含有形成前述氢键的结构单元，如氨基、羟基、羰基等。③获得了这些酰胺类化合物抑菌活性的构效关系。研究成果在《Bioorg. Med. Chem.》《Eur. J. Med. Chem.》《Tetrahedron Lett.》《J. Chem. Res.》《Chem. Heterocyclic Compds》等国际国内学术刊物上发表了18篇与项目相关的学术论文，其中SCIE收录14篇；共申请发明专利10项，授权6项。在人才培养方面，有11名硕士研究生参与该项目，已获硕士学位8人。3名青年教师评为副教授。达到了预期目标。