Design, synthesis, antibacterial activity, and mechanism of novel resveratrol derivatives containing an 1,3,4-oxadiazole moiety

Rice bacterial diseases seriously threaten the development of rice industry in the world, and chemical control is still one of the effective means to control it. To find novel antibacterial agents, 42 resveratrol derivatives were designed and synthesized based on natural product resveratrol as lead structure, and their antibacterial activities were evaluated. Most compounds have excellent antibacterial activities. Among them, the EC50 values of compound B1 against Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas oryzae pv. oryzicola (Xoc) were 4.76 and 8.85 mg/L, respectively. The curative activities of compound B1 against bacterial leaf blight and bacterial leaf streak were 45.57 and 38.40%, and the protective activities were 49.41 and 35.93%, respectively. In addition, compound B1 could change bacterial cell surface morphology by inhibiting biofilm formation and exopolysaccharide production, and increasing membrane permeability, thereby affecting the normal growth of bacteria. Furthermore, transcriptome analysis showed that differential expressed genes were mainly enriched in plant-pathogen interaction pathway and MAPK signaling pathway-plant after compound B1 treated susceptible rice. We will further optimize the structure of compound B1 in future work to find more efficient antibacterial agents.