Background: To further develop potential natural fungicides, two series of new acrylopimaric acid triazole derivatives were synthesized, and their antifungal activities were tested and evaluated.
Results: In vitro antifungal activity results indicated that compound 5m exhibited significant inhibitory activity against Rhizoctonia solani with an half maximal effective concentration (EC50) value of 1.528 mg/L. Its antifungal effect was comparable to that of the commercially available fungicide fluconazole, epoxiconazole and propiconazole (EC50 values of 1.441, 0.815 and 1.173 mg/L). Subsequently, in vivo studies were conducted on compound 5m, which revealed its significant protective and curative effects against R. solani. In addition, physiological and biochemical studies showed that compound 5m could disrupt the morphology and ultrastructure of R. solani mycelium, increase cell membrane permeability, inhibit ergosterol synthesis, and enhance the activity of defense enzymes in rice plants. Three-dimensional quantitative structure-activity relationship (3D-QSAR) studies revealed that the molecular structure significantly influenced the binding of compound 5m to the receptor, thereby enhancing its antifungal activity.
Conclusion: Compound 5m exhibits excellent antifungal activity against R. solani, making it a promising candidate fungicide for the prevention and control of R. solani. © 2024 Society of Chemical Industry.
Keywords: Rhizoctonia solani; action mechanism; antifungal activity; rosin; triazole.
© 2024 Society of Chemical Industry.