Design, synthesis and antifungal mechanism of novel acetophenone derivatives containing 1,3,4-thiadiazole-2-thioethers

Abstract

Plant pathogenic fungi could cause significant losses to agricultural productions. To discover new pesticides with novel structures and unique mechanisms of action, a series of novel acetophenone derivatives containing 1,3,4-thiadiazole-2-thioethers was designed and synthesized. Antifungal bioassay results revealed that E1, E2 and E3 exhibited obvious inhibitory effects against six tested fungi at 100 μg mL⁻¹. The EC₅₀ values of E2 against T. cucumeris and E3 against G. saubinetii were 22.2 and 21.5 μg mL⁻¹, respectively. A morphological study of T. cucumeris treated with E2 and nucleic acid and protein content determination experiments revealed that the target compound can change the permeability of the cell membrane and affect the growth of the hyphae, causing their death. These results provide important information for the further study of the mechanism of action of this series of derivatives.