Synthesis And Biological Activity Of Amide Derivatives Containing Trifluoromethylpyridine Structure

In this paper,two series of seventy-two amide derivatives containing trifluoromethylpyridine structure were designed and synthesized based on the principle of active substructure splicing.The target compounds were characterized by ¹H NMR,¹³C NMR,¹⁹F NMR and HRMS.Xanthomonas oryzae pv.oryzae(Xoo),Xanthomonas axonopodis pv.citri(Xac)and Ralstonia solanacearum(R.solanacearum)was used as the research object,the title compounds was evaluated in vitro for antibacterial activities by turbidimetric assay and the reciprocity between the title compound with excellent antibacterial activity and the Xoo was studied by scanning electron microscopy(SEM)and the antibacterial activity in vivo.In addition,their insecticidal activities against Plutella xylostella(P.xylostella)were evaluated.The research achievements are as follows:1?Twenty-eight amide derivatives containing trifluoromethylpyridine were designed and synthesized.Their antibacterial activities were evaluated.The results of bioactivity tests show that some title compounds have excellent antibacterial activity.Particularly,the compound 6d EC₅₀ value was 54.09 mg L^-1 against Xoo,which was slightly lower than these of BT(59.63 mg L^-1)and TC(86.28 mg L^-1).Compounds 6h and 6z showed excellent activity against Xac and had the much lower EC₅₀ values of51.18 mg L^-1 and 60.68 mg L^-1,respectively than these of BT(76.31 mg L^-1)and TC(101.70 mg L^-1).Compound 6e also exhibited favourable activity against R.solanacearum with the lower EC₅₀ value of 74.88 mg L^-1 compared to TC(79.00 mg L^-1).SEM showed that compound 6d could make Xoo cells deform obviously and eventually rupture,leading to cell death.Meanwhile,compounds 6e and 6k showed moderate insecticidal activity against P.xylostella at 500 mg L^-1.2?Forty-four trifluoromethylpyridine amide derivatives were designed and synthesized,and their antibacterial activities against Xoo,Xac and R solanacearum were studied in vitro.Bioactivity tests indicated that some compounds showed good antibacterial activities.Especially,compounds 17 and 36 had EC₅₀ values of 28.58 mg L^-1 and 42.05 mg L^-1 against Xoo,which were lower than that of BT(EC₅₀=59.63 mg L^-1)and TC(EC₅₀=86.28 mg L^-1).Compounds 25,41 and 44 showed excellent antibacterial activity with EC₅₀ values ranging of 46.91?75.78 mg L^-1,which are lower than that of BT(EC₅₀=76.31 mg L^-1)and TC(EC₅₀=101.70 mg L^-1).The EC₅₀ values against R.Solanacearum for 17(55.29 mg L^-1),42(69.64 mg L^-1)and 44(58.91 mg L^-1)were both much lower than these of TC(76.31 mg L^-1).Particularly,the EC₅₀ of 44against Xoo,Xac and R solanacearum were 61.15 mg L^-1,54.43 mg L^-1 and 58.91 mg L^-1 respectively.SEM showed that compound 17 could deform and rupture the cell membrane of Xoo bacteria.In vivo study showed that good control efficiency of compound 17 against Xoo.The insecticidal activity of some compounds against P.xylostella showed moderate insecticidal activity at the concentration of 500 mg L^-1.