Engineering Research Center of Ecology and Agricultural Use of Wetland, Ministry of Education, Hubei Key Laboratory of Waterlogging Disaster and Agricultural Use of Wetland, College of Agriculture, Yangtze University, Jingzhou 434025, China.
Institute of Pesticides, Yangtze University, Jingmi Road 88, Jingzhou 434025, China.
Molecules. 2023 Oct 14;28(20):7084. doi: 10.3390/molecules28207084.
Crop fungal diseases pose a serious threat to global crop production and quality. Developing new and efficient fungicides is an important measure to control crop diseases. Phenylthiazole was found to be an excellent antifungal skeleton based on our previous study on the structural optimization and biological activity of the natural product thiasporine A. To find new fungicides, 45 phenylthiazole derivatives containing an acylhydrazone moiety were designed and synthesized by the principle of active substructure splicing. Forty-two of the forty-five compounds are novel, except for compounds , , and . Their structures were structurally characterized by H NMR, C NMR, and HRMS. The antifungal activities of the target compounds against , , and were evaluated at 25 μg/mL. The bioassay results revealed that most of these compounds exhibited excellent antifungal activities against and at 25 μg/mL. In particular, compounds , , , , , , and showed the inhibition rate of more than 80% against , with EC values of 1.66, 2.01, 2.26, 1.45, 1.50, 1.29, and 2.65 μg/mL, respectively, which were superior to that of the commercial fungicides Isoprothiolane (EC = 3.22 μg/mL) and Phenazine-1-carboxylic acid (EC = 27.87 μg/mL). The preliminary structure-activity relationship (SAR) results suggested that introducing methyl, halogen, or methoxy at the ortho-position of R and the para-position of R can endow the final structure with excellent antifungal activity against . The current results provide useful data for developing phenylthiazole derivatives as new fungicides for controlling rice blast caused by .
作物真菌病害对全球作物生产和质量构成严重威胁。开发新型、高效的杀菌剂是防治作物病害的重要措施。基于我们之前对天然产物硫色孢菌素 A 的结构优化和生物活性的研究，我们发现苯并噻唑是一种极好的抗真菌骨架。为了寻找新的杀菌剂，我们设计并合成了 45 个含有酰腙部分的苯并噻唑衍生物，其设计原理是基于活性亚结构拼接。除了化合物、和外，这 45 个化合物中有 42 个是新的。它们的结构通过 1 H NMR、13 C NMR 和 HRMS 进行了结构表征。目标化合物在 25 μg/mL 下对、和的抗真菌活性进行了评价。生物测定结果表明，这些化合物中的大多数对 和 具有优异的抗真菌活性，在 25 μg/mL 下，抑制率超过 80%。特别是化合物、、、、、和对 表现出超过 80%的抑制率，其 EC 值分别为 1.66、2.01、2.26、1.45、1.50、1.29 和 2.65 μg/mL，优于商业杀菌剂异丙噻菌胺（EC = 3.22 μg/mL）和吩嗪-1-羧酸（EC = 27.87 μg/mL）。初步的构效关系（SAR）结果表明，在 R 的邻位和 R 的对位引入甲基、卤素或甲氧基可以使最终结构对具有优异的抗真菌活性。目前的结果为开发苯并噻唑衍生物作为防治稻瘟病的新型杀菌剂提供了有用的数据。
