ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

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

Mingzhi Huang, Danling Huang, Aiping Liu, Xingping Liu, Xiaoyang Chen, Weidong Liu, Hui Pei, Jiong Sun, Dulin Yin, and Xiaoguang Wang

National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, China

E-mail: dulinyin@126.com

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 ¹H 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 EC₅₀ 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 LC₅₀ 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.

Keywords: Pyrazole carboxamide; Phenyl thiazole; Bioactivity; Structure–activity relationships

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-017-0198-4

Chemical Papers 71 (11) 2053–2061 (2017)