Discovery and Structural Optimization of 1,2,3,4-Tetrahydro-β-carbolines as Novel Reactive Oxygen Species Inducers for Controlling Intractable Plant Bacterial Diseases
Hongwu Liu, Shanshan Su, Siyue Ma, Ting Li, Fang Wang, Yue Ding, Shi‐Tao Liu, Junrong Zhang, Hongmei Xiang, Xiang Zhou, Song Yang
Abstract
Nowadays, reactive oxygen species (ROS) have been acknowledged as promising bactericidal targets against pesticide-resistant bacteria. Herein, to further excavate more excellent ROS inducers, simple 1,2,3,4-tetrahydro-β-carboline derivatives containing a 3-aminopropanamide moiety were prepared and assessed for their antibacterial potency. Notably, three promising compounds displayed significant antibacterial potency. Compound I 29 exhibits excellent in vitro bioactivity, with an EC 50 value of 5.73 μg/mL, and admirable in vivo activities (protective activity of 55.74% and curative activity of 65.50%) toward Xanthomonas oryzae pv. oryzae . Compound I 16 has good activity in vitro, with an EC 50 of 3.43 μg/mL, and outstanding bioactivities in vivo (protective activity of 92.50% and curative activity of 59.68%) against Xanthomonas axonopodis pv. citri . Compound I 6 shows excellent in vitro bioactivity (EC 50 = 2.86 μg/mL) and significant protective activity (94.02%) for preventing Pseudomonas syringae pv. actinidiae . Antibacterial mechanism investigations indicate that these compounds disrupt the balance of the redox system to kill bacteria. These simple 1,2,3,4-tetrahydro-β-carboline derivatives are promising leads to the discovery of bactericidal agents.