Natural products have ancient history as fascinating sources of pharmaceuticals, agrochemicals as well as NPs-derived drug/pesticide innovation. Its diversiform biological performance and skeleton diversity enable to fill the drug/pesticide discovery pipeline in response to the growing innovation demand. Eugenol, a naturally occurring phenolic compound from plant Eugenia caryophyllata, have been attracting attention in agricultural application. To further extend its value-added utilizations in agricultural application and elucidate the underlying molecule mechanism, the 35 of novel eugenol-derived Schiff bases were herein skillfully prepared by means of natural-products modification strategy. Interestingly, the antifungal activity results indicated that the optimal antifungal molecule was A10, affording an EC50 of 0.850 μg/mL toward Botryosphaeria dothidea (B. d.), which was superior to those of parent eugenol (EC50 > 100 μg/mL) and ferimzone (EC50 > 100 μg/mL). It was illustrated that introduction of Schiff base scaffold into natural eugenol contributed to enhance the antifungal performance. Furthermore, a series of bioassays showed the antifungal behavior of compound A10, which had a powerful disruptive effect on the membrane by triggering reactive oxygen species production in the mycelium. Taken together, this study redeveloped natural eugenol as potential antifungal candidates to control fungal infections by triggering reactive oxygen species production.
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