SuFEx Reaction-Driven Synthesis of New Cyclic Sulfonamide Derivatives With Insecticidal and Fungicidal Bioactivities

A series of cyclic sulfonamides were synthesized through sulfur(VI) fluoride exchange (SuFEx) reactions as potential pesticide candidates. Among the 30 synthesized derivatives, bioassay screening revealed pronounced insecticidal activity against Plutella xylostella, with compound G30 demonstrating optimal efficacy (LC₅₀ = 39.86 mg/L). Furthermore, antifungal evaluation against six plant pathogenic fungi via the mycelial growth rate method identified six compounds (G11, G16, G17, G19, G23, and G25) with exceptional activity against Rhizoctonia solani, exhibiting EC₅₀ values ranging from 5.99 to 17.54 mg/L. Notably, compound G11 (EC₅₀ = 5.99 mg/L) displayed remarkable preventive (79.20%) and curative (90.73%) efficacy against R. solani on rice plants at 400 mg/L. Although these values were marginally lower than those of the commercial fungicide thiabendazole, the results highlight the therapeutic potential of this compound. This study provides new perspectives for developing cyclic sulfonamides as innovative lead structures in agrochemical discovery, demonstrating dual pesticidal and antifungal functionalities worthy of further optimization.