Design, synthesis and biological evaluation of 1H-pyrazole-5-carboxamide derivatives as potential fungicidal and insecticidal agents

A series of novel 1H-pyrazole-5-carboxamide compounds containing the phenyl thiazole moiety were designed and synthesized by a facile method, and their structures were characterized by 1 H NMR, mass spectrometry and elemental analysis. Bioassay results showed that most of the title compounds showed potent fungicidal activities against Erysiphe graminis and insecticidal activity against Aphis fabae. Especially, compound 9b has EC 50 values of 3.04 mg/L against Erysiphe graminis , of which the fungicidal activity is better than that of the commercial fungicide Thifluzamide and Azoxystrobinare; compound 9l has LC 50 values of 3.81 mg/L against Aphis fabae , which was comparable with the commercial insecticide Tolfenpyrad. It is suggested that 1H-pyrazole-5-carboxamide compounds containing the phenyl thiazole moiety could be considered as a precursor structure for further design of pesticides. Graphical Abstract A series of novel 1H-pyrazole-5-carboxamide compounds containing the phenyl thiazole moiety were designed and synthesized by a facile method, and their structures were characterized by 1 H NMR, mass spectrometry and elemental analysis. Bioassay results showed that most of the title compounds showed potent fungicidal activities against Erysiphe graminis and insecticidal activity against Aphis fabae. Especially, compound 9b has EC 50 values of 3.04 mg/L against Erysiphe graminis , of which the fungicidal activity is better than that of the commercial fungicide Thifluzamide and Azoxystrobinare; compound 9l has LC 50 values of 3.81 mg/L against Aphis fabae , which was comparable with the commercial insecticide Tolfenpyrad. It is suggested that 1H-pyrazole-5-carboxamide compounds containing the phenyl thiazole moiety could be considered as a precursor structure for further design of pesticides.