Synthesis and antifungal activity of polyphenol ether derivatives against plant pathogenic fungi in vitro and in vivo

Phytopathogenic fungi have been considered as an enormous threat in the agricultural system. In our search of new antifungal natural products, twenty-seven polyphenol ether derivatives were synthesized. Their structures were elucidated based on extensive spectroscopic analysis. The results suggest that compound 8, 13, 15 and 21 exhibited strong antifungal activities against R. solani and S. sclerotiorum in vitro, and compound 13 displayed the best antifungal efficacy toward E. graminis in vivo. This work provides an effective strategy for searching antifungal candidate agents.