Design, Synthesis, and Antifungal Activity of Novel Stilbene Cyclohexyl Sulfonamide Derivatives against Botrytis cinerea.

Botrytis cinerea has become an enormous threat to crop production worldwide. In order to discover novel antifungal molecules with high control efficacy against Botrytis cinerea, a series of cyclohexyl sulfonamide derivatives containing stilbene fragments were designed and synthesized using chesulfamide as a lead compound. Bioassay results indicated that these novel compounds have moderate to excellent in vivo antifungal activity. Compounds II-9, II-11, and II-15 have outstanding control efficacy on strawberries (97.0%, 92.8%, 91.6%) at 400 μg/mL, surpassing that of control agents boscalid and procymidone (51.4%, 85.0%). Compounds II-15, II-25, II-27, and II-30 have similar activity (up to 90.9%) on tomato pots at 200 μg/mL as control agents boscalid (85.4%). The preliminary mode of action of compound II-15 was discussed by scanning electron microscope observation, permeability measurement, and a propidium iodide staining experiment. Transcriptome analysis was performed to investigate the influence of compound II-15 on gene expression. Additionally, DFT calculation was used to analyze the molecular orbitals and electrostatic potential distribution of compound II-15. This work indicates that compound II-15 can be considered a promising candidate for novel fungicides against Botrytis cinerea.