Design, Synthesis, and Biological Evaluation of Pyrazol‐5‐yl‐Phenylacetamide Derivatives as Potential Fungicidal Agents
Guo‐Tai Lin, Wei Wang, Xi‐Zhe Zhang, Li Luo, Gong Xu, Dan XuABSTRACT
Fungal infestation in crops can greatly reduce both yield and quality. To discover new fungicides, pyrazol‐5‐yl‐phenylacetamide derivatives were synthesized by elongating the carbon chain of the lead compound pyrazol‐5‐yl‐benzamides. These derivatives were assessed for their effectiveness against fungi. Compound C‐13 displayed significant antifungal activity against Sclerotinia sclerotiorum , with an EC 50 value of 2.51 mg/L. Additionally, compound C‐16 showed effective antifungal properties against Valsa mali , with an EC 50 value of 3.14 mg/L. Particularly noteworthy is the superior antifungal efficacy of compound C‐42 against Gaeumannomyces graminis , with an EC 50 value of 1.81 mg/L, significantly outperforming Fluxapyroxad (EC 50 = 21.01 mg/L). Molecular docking and SDH enzymatic inhibition assay results provided insights into the potential mechanism of action of compound C‐42 . This study supports the development of pyrazol‐5‐yl‐phenylacetamides as promising fungicides, particularly against G. graminis .