title: Structural modification of sanguinarine and chelerythrine and their antibacterial activity.
abstract: 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.
authors.affiliation: College of Life Science, Northwest A&F University, P.R. China.
authors.forename: Fang
authors.initials: F
authors.lastname: Miao
authors.forename: Xin-Juan
authors.initials: XJ
authors.lastname: Yang
authors.forename: Le
authors.initials: L
authors.lastname: Zhou
authors.forename: Hai-Jun
authors.initials: HJ
authors.lastname: Hu
authors.forename: Feng
authors.initials: F
authors.lastname: Zheng
authors.forename: Xu-Dong
authors.initials: XD
authors.lastname: Ding
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Sun
authors.forename: Chun-Dong
authors.initials: CD
authors.lastname: Zhou
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
mesh_terms: D016980:Aeromonas hydrophila / Q000187:drug effects; D000470:Alkaloids / Q000737:chemistry* / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D053119:Benzophenanthridines / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects; D007546:Isoquinolines / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D028101:Papaveraceae / Q000737:chemistry; D016979:Pasteurella multocida / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects; D013329:Structure-Activity Relationship
chemical_list: D000470:Alkaloids; D000900:Anti-Bacterial Agents; D053119:Benzophenanthridines; D007546:Isoquinolines; C005705:sanguinarine; C016299:chelerythrine