基于激发植物免疫为导向的嘧啶酮类高效抗病毒剂设计合成及作用机制研究

In view of the current situation of plant virus disease, the variety of virus, the rapid variation and the lack of effective and broad-spectrum control agents and measures in China, the effective, safety, broad-spectrum antiviral agents are urgently needed to develop in the future. Based on stimulated plant immunity, the design idea of virus inhibition and plant immunity together, constructing plant immune molecules on skeleton of pyrimidine, this project will focus on the key scientific issues related to how to discover and design the efficient antiviral agents to control vegetable viruses and new molecular targets with the combination of chemical and biological research strategies. The strategies of “inhibition of viral replication” as well as “antiviral activity induced by plant host” will be combined to tackle this challenge, which include study on molecular design and action mechanism, design and efficient synthesis of pyrimidine derivatives, target analysis of high activity pyrimidine molecule against plant virus and molecular design based on target structure. Preliminary activity evaluation of new pyrimidine derivatives against some plant viruses (TMV, CMV, PVY), highly active broad-spectrum candidate compounds are developed. Using light crosslinking technology and proteomics technology, the project will explore the important proteins, nucleic acids and biological networks involved in the interaction of active compounds, the viruses and the hosts in the process of the pathogen pathogenicity and the host immune response. It lays a theoretical foundation for the development of anti-plant viral agents with high activity, novel structure, environmental friendliness and ecological security.

针对当前我国植物病毒病危害大、病毒种类多、变异快及缺乏高效广谱的防治药剂及措施的现状，急需开发对病毒有效而对植物安全的高效广谱的抗病毒药剂。本项目基于激活植物免疫为导向，同时考虑抑制病毒本身和激活植物免疫的设计思路，将具有植物免疫活性基团杂化于具有广谱抗病毒活性嘧啶酮的骨架中，围绕构建高效农药先导分子设计与发现新的分子靶标关键科学问题，采用化学与生物学相结合的研究策略，初步评价新型嘧啶酮衍生物对常见植物病毒（如黄瓜花叶病毒、马铃薯晚疫病毒、烟草花叶病毒等）的广谱抗病毒活性，望获得高活性广谱的候选化合物。并进一步以高活性候选化合物，采用光交联技术和蛋白组学技术，科学认识病原致病与寄主抗病这两个过程中病毒与寄主及活性分子相互作用的关键致病蛋白、免疫激活效应蛋白和核酸之间的生物网络，为从小分子作用机制开发活性高、结构新颖、环境友好与生态安全的抗植物病毒药剂奠定理论基础。

针对当前我国植物病毒病危害大、病毒种类多、变异快及缺乏高效广谱的防治药剂及措施的现状，急需开发对病毒有效而对植物安全的高效广谱的抗病毒药剂。本项目提出在抗病毒新化合物结构设计中将抗植物病毒的化学治疗片段和免疫治疗片段进行成功杂化，已完成具有植物免疫活性片段二硫缩醛、噁二唑、萘乙酸及吲哚乙酸引入具有广谱抗病毒活性嘧啶酮化合物中，共合成了94个新型结构化合物，并通过核磁、红外及高分辨质谱对其结构进行了表征。通过抗植物病毒活性筛选，筛选出化合物ms-29, J-19, 6k对烟草花叶病毒的抗病毒活性远远高于对照药剂宁南霉素和毒氟磷，可作为候选化合物进一步进行应用开发。本项目选择化合物 6k与病毒外壳蛋白TMV-CP进行计算机分子对接，结合力的大小与化合物的抗病毒活性具有相同趋势，进一步说明化合物的抗病毒活性的初步作用机制是作用于病毒外壳蛋白TMV-CP。从化合物6k与TMV-CP的三维结合模型图可知，化合物6k通过与GLY135的一个氢键(距离= 2.8 Å)很好地与TMV-CP结合。此外，化合物6k还与TMV-CP通过烷基相互作用和ti -烷基与TYR139相互作用(距离= 5.0 Å)很好地结合在一起。通过以上对接结果，再结合生物测试活性数据，表明化合物6k比其他化合物具有更高的活性，这将有助于我们进一步的结构优化。基于上述药物分子初步作用机制，进行高效低风险广谱抗病毒活性小分子设计与合成，推动创新药物的高效化及产业化。