Synthesis, characterization, and fungicidal activity of novel Fangchinoline derivatives

A series of new Fangchinoline derivatives with the carbamate moiety (compounds 1a-1l, 2a-2l) were synthesized by utilizing phenolic hydroxyl to react with isocyanate. The potential fungicidal activity of all the target compounds has been screened against six species of plant pathogen fungi, including Pp. adianticola (Phomopsis adianticola), A. adianticola (Altermaria adianticola), C. fructicola (Colletotrichum fructicola), P. theae (Pestalotiopsis theae), P. adianticola (Phoma adianticola), and G. zeae (Gibberella zeae). Almost all the derivatives showed better fungicidal activity than Fangchinoline. Compounds 1f, 1g, 1h, and 1k exhibited obviously better activity against G. zeae, and Pp. adianticola than Azoxystrobin. Especially compounds 1k displayed high fungicidal activity against G. zeae, Pp. adianticola, and P. theae.