Design, synthesis and antifungal activities of novel pyrrole- and pyrazole-substituted coumarin derivatives

We synthesized a series of novel pyrrole- and pyrazole-substituted coumarin derivatives and evaluated their antifungal activity against six phytopathogenic fungi in vitro . The primary assay results demonstrated that some designed compounds displayed potent activities. Among them, compounds 5g , 6a , 6b , 6c , 6d and 6h exhibited more effective control than Osthole against Cucumber anthrax and Alternaria leaf spot. Furthermore, compound 5g displayed stronger antifungal activity against Rhizoctorzia solani (EC 50 = 15.4 µg/mL) than positive control Osthole (EC 50 = 67.2 µg/mL). Graphical abstract