Novel Uracilphenyl sulfonamide-based inhibitors of protoporphyrinogen oxidase: Design, synthesis, and herbicidal activity

Herein, we aimed to develop effective herbicidal compounds by synthesizing 26 novel uracil derivatives containing sulfonamide groups based on the active group splicing principle, with saflufenacil as the reference compound. The structures of the final products were confirmed through H-1 NMR, C-13 NMR, and HRMS analyses. According to the results, 21 and 19 compounds exhibited outstanding (80 %-100 %) and 60-100 % control efficacies against broadleaf weeds (Zinnia elegans and Abutilon theophrasti) at concentrations of 150 g/hm(2) and 37.5 g/hm(2), respectively. Notably, compound 2a demonstrated 100 % control efficacy against Zinnia elegans even at the lowest tested concentration of 9.375 g/hm(2). On the other hand, the examined compounds exhibited minimal efficacy against other grass weeds, such as Setaria glauca and Echinochloa crusgalli. Furthermore, molecular docking analysis revealed that compound 2a formed hydrogen bonds with Protoporphyrinogen Oxidase (PPO).Studies of the electrostatic potential analysis of the molecular surface showed that the highly active compounds 2a and saflufenacil have similar charge distributions, which may play an important role in the docking of the compounds with their target receptors.These findings offer valuable insights and guidance for developing more effective herbicides, paving the way for future advances in weed control tactics.