N-[2-[(3-Chlorophenyl)amino]-phenyl]-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxamide: Synthesis, Crystal Structure, Molecular Docking and Biological Activities.

In continuation of our previous research on the development of novel pyrazole-4-carboxamide with potential antifungal activity, compound SCU2028, namely N-[2-[(3-chlorophenyl)amino]phenyl]-3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxamide, was synthesized by new method, structurally characterized by IR, HR-ESI-MS, H- and C-NMR spectra and further identified by single-crystal X-ray diffraction. In pot tests, compound SCU2028 showed good in vivo antifungal activity against Rhizoctonia solani (R. solani) and IC value of it was 7.48 mg L . In field trials, control efficacy of compound SCU2028 at 200 g.a.i. ha was 42.30 % on the 7 day after the first spraying and 68.10 % on the 14 day after the second spraying, only slightly lower than that of thifluzamide (57.20 % and 71.40 %, respectively). Further in vitro inhibitory activity showed inhibitory ability of compound SCU2028 was 45-fold higher than that of bixafen and molecular docking of compound SCU2028 to SDH predicted its binding orientation in the active site of the target protein SDH. These results suggested that compound SCU2028 was a potential fungicide for control of rice sheath blight.