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

Novel amide derivatives containing a pyridine moiety: design, synthesis as potential fungicides

Xin Luo, Yifang Chen, Yu Wang, Zhifu Xing, Ju Peng, Chongfen Yi, and Jixiang Chen

National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University, Guiyang, China

E-mail: jxchen@gzu.edu.cn

Received: 6 August 2022  Accepted: 20 June 2023

Abstract:

To discover new fungicides, a series of amides derivatives containing a pyridine moiety were designed and synthesized by grafting the pyridine of fluopyram into the boscalid structure. The EC₅₀ values of compounds 9, 11, and 15 against Rhizoctonia solani (R. solani) were 0.19, 0.83, and 0.09 mg/L, respectively, which were better than the control agent boscalid (1.70 mg/L). The EC₅₀ values of compounds 15 against Monilinia fructicola (M. fructicola) were 5.46 mg/L. The protective activity of compound 15 against rice sheath blight was 74.1% at 100 mg/L, which was better than boscalid (54.6%). In addition, the inhibition of SDH by compound 15 was 0.11 μmol/L, which was better than that of boscalid (8.22 μmol/L). The molecular docking results were consistent with the antifungal activity and SDH inhibitory activity. Interestingly, compound 15 can significantly reduce the expression level of SDHB and SDHD. Compound 15 can be used as a lead structure to develop SDH inhibitors.

Keywords: Amide derivatives; Antifungal activity; Molecular docking; Succinate dehydrogenase inhibitors; Mycelial morphology; RT-qPCR

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-02938-6

Chemical Papers 77 (10) 6299–6310 (2023)