College of Life Science, Northwest A&F University, P.R. China.
Nat Prod Res. 2011 May;25(9):863-75. doi: 10.1080/14786419.2010.482055.
In this study, five derivatives of sanguinarine (1) and chelerythrine (2) were prepared, with 1 and 2 as starting materials, by reduction, oxidation and nucleophilic addition to the iminium bond C=N+. The structures of all compounds were elucidated on account of their MS, ¹H-NMR and ¹³C-NMR data. The antibacterial activities of all compounds were screened, using Staphylococcus aureus, Escherichia coli, Aeromonas hydrophila and Pasteurella multocida as test bacteria. The minimum bacteriostatic concentration and minimum bactericidal concentration of the active compounds were determined by the turbidity method. The structure-activity relationships of 1 and 2 were discussed. The results showed that 1, 2 and their pseudoalcoholates were found to be potent inhibitors to S. aureus, E. coli and A. hydrophila, while the other derivatives were found to be inactive. The pseudoalcoholates might be the prodrugs of 1 and 2. The iminium bond in the molecules of 1 or 2 was the determinant for antibacterial activity, and the substituents at the 7 and 8 positions influenced the antibacterial activities of 1 and 2 against different bacteria.
在这项研究中，以血根碱（1）和白屈菜红碱（2）为起始原料，通过还原、氧化和亲核加成到亚胺键 C=N+，制备了 5 个血根碱和白屈菜红碱的衍生物。根据它们的 MS、1H-NMR 和 13C-NMR 数据，解析了所有化合物的结构。用金黄色葡萄球菌、大肠杆菌、嗜水气单胞菌和多杀巴斯德氏菌作为测试细菌，筛选了所有化合物的抗菌活性。用浊度法测定了活性化合物的最小抑菌浓度和最小杀菌浓度。讨论了 1 和 2 的构效关系。结果表明，1、2 及其假醇化物对金黄色葡萄球菌、大肠杆菌和嗜水气单胞菌具有很强的抑制作用，而其他衍生物则没有活性。假醇化物可能是 1 和 2 的前药。分子中的亚胺键是 1 或 2 抗菌活性的决定因素，7 和 8 位的取代基影响 1 和 2 对不同细菌的抗菌活性。
