Synthesis, Crystal Structure and Antifungal Activity of 1-(3,3 -Dimethyl-2-oxobutyl)-N-phenyl-1H-1,2,4-triazole-3-carboxamide

Abstract

Fungicides play a vital role in protecting crops from fungal damage.However, fungicide re-sistance is one of the most important issues in modern agriculture. Hence, it is very neces-sary to develop new fungicides constinuously.Triazole compounds have received consider-able interest in agricultural chemistry due to a novel action mode, extremely high activity against phytopathogenic fungi, low acute toxicity to mammals, and environmentally benign characteristics. The title compound 1-(3,3-dimethyl -2-oxobutyl)-N-phenyl-1H-1,2,4-triazole-3-carboxamide 5, synthesized using methyl 1H-1,2,4 -triazole-3-carboxylate 1 as the start material, was successfully obtained via multi-ple synthesis route and finally characterized by 1H NMR,13C NMR, HRMS and single-crystal X-ray diffraction. Compound 5 (C15H18N4O2, Mr = 287.1500) belongs to the orthorhombic system, space group Pn21a, with a = 14.49451(11)and#197;, b = 20.34686(18)and#197;, c = 10.17021(9)and#197;, V =2999.38(4) and#197;3, Z = 8, Dc= 1.268 g/cm3, T = 293.55(14) K, μ (CuKα) = 0.710 mm-1, F (000) =1216.0, the final R=0.0448, and wR = 0.1260 with Iandgt;=2σ (I). Fur-thermore, the results from biological assays indicated that the title compound exihibited a similar antifungal activity（EC 50 =8.98 mg. L-1）compared to triadimefon (EC50=5.6 mg.L-1)against G. cingulatal. And had different degrees of weak activity against other phy-topathogenic fungi, including A. solani, S. sclerotiorum, G. saubinetii and T. cucumeris. Po-tentially, the result lay the foundation for the development of novel fungicides