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In order to explore more efficient sulfonamides against <i>Botrytis cinereal</i>, 36 novel cyclohexylsulfonamides were synthesized by <i>N</i>-(3-dimethylaminopropyl)-<i>N</i>&#8242;-ethylcarbodiimide (EDCI) and 1-hydroxybenzotriazole (HOBt) condensation reaction using chesulfamide as a lead compound, introducing thiazole and pyrazole active groups. Their structures were characterized by ¹H-NMR, ¹³C-NMR, mass spectrum (MS), and elemental analysis. Compound III -31 was further confirmed by X-ray single crystal diffraction. The in vitro and in vivo fungicidal activities against <i>B. cinerea</i> were evaluated by three bioassay methods. The results of mycelial growth demonstrated that median effective concentration (EC₅₀) values of nine compounds were close to boscalid (EC₅₀ = 1.72 &#181;g/mL) and procymidone (EC₅₀ = 1.79 &#181;g/mL) against <i>B. cinerea</i> (KZ-9). In the spore germination experiment, it was found that compounds III-19 and III-31 inhibited germination 93.89 and 98.00%, respectively; at 10 &#181;g/mL, they approached boscalid (95.97%). In the tomato pot experiment, the control effects of two compounds (III-21 and III-27) were 89.80 and 87.90%, respectively, at 200 &#181;g/mL which were significantly higher than boscalid (81.99%). The structure&#8722;activity relationship (SAR) was also discussed, which provided a valuable idea for developing new fungicides.