| Pyrazolecarboxamide dervativites played important roles in the field of pesticides due to their broad-spectrum bioactivities, such as insecticides, fungicides, and herbicides. At the same time, pyrazolecarboxamide dervativites have drawn more attentions from the world because of their unique mechanism of action, safety, high efficiency, low toxicity, low residue and many replaced position.In order to investgate new pyrazolecarboxmides derivatives with higher biological activities, a series of 1-(3-chloropyridin-2-yl)-5-(trifluoromethyl)-1Hpyrazole-4-carboxamide derivatives were designed and synthesized. Their structures were characterized by IR, 1H NMR, 13 C NMR, MS and elemental analysis.The antifungal activities of all title compounds on G.zeae, F.oxysporum, C. mandshurica, B.cinerea, G.cingulata, P.infestans, R.solani, B.cinerea, Sclerotiua sclerotiorum were tested by the mycelial growth rate method. The results showed that the series compounds exhibited certain of inhibitory activity against these nine Fungi at the concentration of 100 μg/m L. Especially, the compound I4, I5, I6, I7, I16 showed to inhibit the growth of G.zeae at 88.0± 0.6%, 76.3± 3.5%, 77.0±3.9%, 71.6±7.0% and 85.7±5.3%. Compounds I4, I5, I6, I7, I8, I16 were showed to inhibit the growth of C. mandshurica at 77.5±0.8%, 70.8±3.3%, 70.3±0.8%, 72.9±3.5%, 70.0±3.2%, 67.6±3.4%. Compounds I4, I5, I6, I7, I8, I16 were showed to inhibit the growth of F.oxysporum at 80.0±0.9%, 73.2±3.3%, 78.2±6.5%, 72.1±3.4%, 64.7±2.8%, 66.5±2.8%. Compounds I1, I3, I25 were showed to inhibit the growth of Botrytis cinerea at 67.0±2.3%, 77.1±3.2%, 76.6±2.8%. Compounds I8, I15, I16, I41 were showed to inhibit the growth of P. infestans at 61.3±2.7%, 63.2±1.4%, 62.6±1.4%, 83.9±5.1%. Compounds I4, I16 were showed to inhibit the growth of Rhizoctonia solani at 62.3±1.4%, 78.7±0.9%. Compounds I1, I8, I15, I17, I26 were showed to inhibit the growth of Sclerotiua sclerotiorum at 60.0±2.7%, 67.8±3.0%, 3.2±1.4%, 62.6±3.2% and 61.3±3.6%. By comparing the structure of these compounds, it was found that the compound containing 4-pyridine showed relatively good antifungal activity against G.zeae, F.oxysporum, C.mandshurica. The antifungal activity of substituted 4-pyridine with electron withdrawing group was better than that of corresponding compounds with electron-donating. The compounds containing 4-pyridine and alkyl showed relatively good antifungal activity against P. infestans, T.cucumeris, S. sclerotiorum, and the antifungal activity increased with the increasing of chain length.The antibacterial activity was evaluated against tobacco bacterial and rice bacterial blight pathogen. It was observed that the inhibited rate of compound I9 against tobacco bacterial was 91.9±1.3% at the concentration of 100 μg/m L. The inhibited rate of compounds I11, I12, I13, I20, I23, I30, I31, I36, I38, I40 against rice bacterial blight pathogen were 71.8±1.5%, 76.3±5.2%, 84.9±1.7%, 83.4±1.6%, 87.1±1.2% at the concentration of 100 μg/m L. By comparing the structure of these compounds, it was found that the antibacterial activity against rice bacterial blight pathogen of the compound containing benzene or alkanes were better than the others because of space steric effect, and the antibacterial activity of substituted phenyl with electron withdrawing group was better than that of corresponding compounds with electron-donating.The leaf dipping assay method was used for Plutella xylostella tests. It was observed that compound I31 indicated 45% insecticidal activities against P.xylostella at 500 μg/m L. |
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