Design, Synthesis, and Antibacterial Activity of Stilbene Derivatives against Phytopathogenic Bacteria

The increasing resistance of phytopathogenic bacteria to chemical pesticides has underscored the urgent need for novel bactericidal agents. In this study, we designed, synthesized, and evaluated a series of stilbene derivatives for their antibacterial activity against six strains of plant-pathogenic bacteria. Among them, compound ST-A-8 showed the optimal activity against Xanthomonas oryzae pv oryzae (Xoo) and Erwinia aroideae, with both MIC values of 1.56 μg/mL, which was more potent than the commercialized antibacterial agent thiodiazole copper. Furthermore, the mechanism of ST-A-8 on Xoo was preliminarily investigated, and the results showed that ST-A-8 inhibited the biofilm formation as well as the production of extracellular polysaccharides in Xoo. Additionally, it disrupted the integrity of the cell membrane and increased the production of ROS, leading to lipid peroxidation of the cell membrane. Therefore, compound ST-A-8 may serve as a potential novel bactericide for the control of plant bacterial diseases.