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Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines
Published on: June 23, 2019
Design, Synthesis, and Insecticidal Activities of Imidazo[4,5-b]Pyridine Compounds Containing Amino Fragment
Yunfeng Yao1, Xinlin Li2,3, Liqi Zhou2
1School of Hunan Normal University, Changsha, China.
Abstract:
In order to develop new insecticides to solve the problem of pests, a series of imidazo[4,5-b]pyridine compounds containing amino fragments were synthesized and characterized by proton nuclear magnetic resonance (1H NMR), carbon-13 NMR (13C NMR), and high-resolution mass spectrometry. The preliminary bioassay result indicated that most of the synthesized compounds exhibited excellent insecticidal activities against Nilaparvate lugens and Mythimna separata. Especially, 5-(ethylsulfonyl)-6-(3-methyl-6-(trifluoromethyl)-3H-imidazo[4,5-b]pyridin-2-yl)-N-(4-methylbenzyl)pyridin-2-amine (8n) exhibited 46.85 % mortality against N. lugens at 5 mg/L, better than Oxazosulfyl (0.00 % at 5 mg/L). Meanwhile, 5-(ethylsulfonyl)-6-(3-methyl-6-(trifluoromethyl)-3H-imidazo[4,5-b]pyridin-2-yl)-3-phenylpyridin-2-amine (10a) exhibited 100.00 % mortality against M. separata and Plutella xylostella at 1 mg/L, better than Oxazosulfyl against M. separata (0.00 % at 1 mg/L) and P. xylostella (96.67 % at 1 mg/L). Further, the preliminary structure-activity relationship was discussed. The work demonstrated that the prepared compounds containing amino fragments imidazo[4,5-b]pyridin can supply certain hints by structure optimization for the development of new insecticides.
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