Synthesis and biological activity of novel N-(3-furan-2-yl-1-phenyl-1H-pyrazol-5-yl) amides derivatives

A series of novel N-(3-furan-2-yl-1-phenyl-1H-pyrazol-5-yl) amides derivatives were designed and synthesized. Their structures were confirmed by ¹H NMR, ¹³C NMR and HRMS. All title compounds were evaluated for their herbicidal and antifungal activities. Preliminary bioassay results indicated that the title compounds showed good to moderate herbicidal activity at 1000 mg/L. Compound 6q presented the best activity against Digitaria sanguinalis (L) Scop., Amaranthus retroflexus L. and Arabidopsis thaliana with an inhibition degree of five. Compound 6d also showed an inhibition degree of five against D. sanguinalis. In addition, at 50 mg/L, most compounds exhibited good in vitro antifungal activity against Sclerotinia sclerotiorum, with compound 6c showing over 90% antifungal activity against S. sclerotiorum and Pellicularia sasakii.