The discovery of 3-fluoroalkyl indoles as potential antifungal agents to control tomato gray mold caused by Botrytis cinerea

Indole derivatives are a class of important heterocyclic natural products, which usually possess extensive bioactivities. In order to develop indole derivatives as potential fungicidal agents, a series of 3-perfluoroalkyl indole derivatives were prepared and investigated for their antifungal activities. The present data revealed that compound 3a was effective against eight test phytopathogenic fungi in vitro, and had the highest antifungal activity against B. cinerea, with an EC50 value of 0.94 µg/mL. Additionally, this indole exhibited excellent protective and curative efficacies against tomato gray mold in vivo. A possible mechanism of antifungal action for this compound was also explored. This study demonstrated that 3-perfluoroalkyl indole derivatives could potentially have utility as botanical fungicides for the management of phytopathogenic fungi.