Antifungal Activity of Griseofulvin Derivatives against Phytopathogenic Fungi in Vitro and in Vivo and Three-Dimensional Quantitative Structure–Activity Relationship Analysis

With environmental pollution, residual hazards accumulate and severe drug resistance and many other problems appear; some highly toxic drugs have been banned, and antifungal agents are far from satisfactory. Natural products play an important role in the discovery and development of new pesticides. The natural product griseofulvin (1) has been known as an antifungal agent in the treatment of dermatomycoses for decades. In this study, a series of new griseofulvin derivatives were synthesized with good yields. Their structures were characterized by 1H and 13C nuclear magnetic resonance and high-resolution mass spectrometry (electrospray ionization). The antifungal activities of griseofulvin analogues were first evaluated against five phytopathogenic fungi (Cytospora sp., Colletotrichum gloeosporioides, Botrytis cinerea, Alternaria solani, and Fusarium solani) in vitro. Of significance is that most of them showed excellent antifungal activities against C. gloeosporioides. The antifungal activities of the fou...