Design, Synthesis, and Antifungal Activity of Novel Stilbene Cyclohexyl Sulfonamide Derivatives against <i>Botrytis cinerea</i>

<i>Botrytis cinerea</i> has become an enormous threat to crop production worldwide. In order to discover novel antifungal molecules with high control efficacy against <i>Botrytis cinerea</i>, 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 <i>in vivo</i> antifungal activity. Compounds <b>II-9</b>, <b>II-11</b>, and <b>II-15</b> 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 <b>II-15</b>, <b>II-25</b>, <b>II-27</b>, and <b>II-30</b> 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 <b>II-15</b> 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 <b>II-15</b> on gene expression. Additionally, DFT calculation was used to analyze the molecular orbitals and electrostatic potential distribution of compound <b>II-15</b>. This work indicates that compound <b>II-15</b> can be considered a promising candidate for novel fungicides against <i>Botrytis cinerea</i>.