Design, synthesis, and antifungal activity of flavonoid derivatives containing thiazole moiety

A series of flavonoid derivatives containing thiazole scaffold were designed, synthesized and evaluated for their inhibition effects against Rhizoctonia solani , Fusarium graminearum , Gaeumannomyces graminis , Alternaria solani , Botrytis cinerea , and Alternaria mali . The antifungal bioassays results in vitro indicated that some target compounds showed good antibacterial activity against the tested plant fungi, which were better than that of the flavonoid natural product quercetin. Strikingly, the title compounds 6a , 6b , and 6f demonstrated obvious antifungal activities against Rhizoctonia solani with EC 50 value of 9.6, 35.5, and 21.5 μg/mL, respectively. The EC 50 value of compound 6b against Gaeumannomyces graminis reached 2.7 μg/mL. Graphical abstract