Simplification of Natural β-Carboline Alkaloids to Obtain Indole Derivatives as Potent Fungicides against Rice Sheath Blight.

ABSTRACT: The increasing resistance of rice sheath blight caused by Rhizoctonia solani highlights the need for highly effective and environmentally benign agents. Natural β-carboline alkaloids were simplified to obtain a series of indole derivatives, and their fungicidal activity and preliminary mode of action against R. solani were also evaluated. The initial hit indole (7) displayed significant fungicidal activity with an EC50 value of 25.56 μg/mL, and was selected for further optimization. Importantly, compound 55, the most active compound, had an EC50 value of 0.62 μg/mL, and approximately 300-fold more potent than validamycin A (EC50 = 183.00 μg/mL). In vivo bioassay also demonstrated that compound 55 showed better fungicidal activities than validamycin A. Moreover, the mechanism studies reveal

SUBMITTER: Zeng J 

PROVIDER: S-EPMC7179428 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature