Study On Synthesis And Antifungal Activities Of Dibenzofuran Derivatives

Dibenzofran not only widely used in pharmaceutical industry and chemical industry, also has a variety of biological activity. Through the research of the dibenzofuran derivatives, we found a new and simple synthetic method to complete the synthesis, and the synthetic conditions were optimized. We reached the following conclusions by experiment:1 To employ the palladium acetate as the catalyst without the ligands, ethanol as the solvent, and the refluxing condition. Compared the traditional conditions, the present procedure can not only achieve the desired yield, but also has the main advantages of milder conditions and shorter reaction time.2 Start with the phenols and the o-nitro halogens, followed by the copper catalyzed Ullmann reaction, getting the fluoroborate crystals through the diazotization of aromatic nitro, and finally generated 8 dibenzofuran derivatives catalyzed by the palladium acetate, all of these confirmed by 1H-NMR.3 Apply mycelium growth rate method, 8 compounds were determined by antifungal activity of five plant pathogenic fungi. We choose the Alternaria solani,Colletotrichum gloeosporioide,Pyricularia grisea,Botrytis cinerea,Fusarium solani as tested phytopathogenic fungi, choose the acetone as control. Compounds 4a, 4b,4c have satisfactory inhibitory in all of five tested fungi, the inhibition rates reached above 50%, while the 8 compounds with dibenzofuran skeleton have good inhibitory effect in Botrytis cinerea ,the inhibitory rate reached above 69%.