Synthesis and biological activities of novel trifluoromethylpyridine amide derivatives containing sulfur moieties

A series of trifluoromethylpyridine amide derivatives containing sulfur moieties (thioether, sulfone and sulfoxide) was designed and synthesized. Their antibacterial activities againstXanthomonas oryzaepv.oryzae(Xoo),Ralstonia solanacearum(R. solanacearum) and insecticidal activities againstP. xylostellawere evaluated. Notably, the half-maximal effective concentration (EC50) value of sulfone-containing compoundF10is 83 mg L(-1)againstXoo, which is better than that of commercial thiodiazole copper (97 mg L-1) and bismerthiazol (112 mg L-1). Thioether-containing compoundsE1,E3,E5,E6,E10,E11andE13showed much higher activities againstR. solanacearumwith the EC(50)value from 40 to 78 mg L-1, which are much lower than that of thiodiazole copper (87 mg L-1) and bismerthiazol (124 mg L-1). Generally, most of the sulfone-containing compounds and sulfoxide-containing compounds showed higher activities againstXoothan that of the corresponding thioether-containing compound, but most of the thioether-containing compounds contributed higher antibacterial activities againstR. solanacearum. Furthermore, title compoundsE3,E11,E24andG2showed good insecticidal activities of 75%, 70%, 70% and 75%, respectively.