抄録
N-Dodecylpyridinium iodide derivatives having hydroxyl, amino, methyl, chloro and/or trifluoromethyl groups on the pyridine ring were synthesized from the corresponding pyridines and dodecyl iodide under 80 MPa in order to delineate a quantitative structure-activity relationship. The bactericidal and bacterioclastic activity of the derivatives against Escherichia coli K12 W3110 was strongly affected by the kind of substituent groups these derivatives possesed and their positions. The electron-releasing groups such as amino and methyl groups markedly enhanced such activity, while the electron-attracting groups such as carboxyl and carbamoyl groups reduced it. The bactericidal activity of derivatives was dependent on acidic dissociation constant of the corresponding pyridines and the chemical shift of methylene protons adjacent to the ammonium nitrogen. When bactericidal activity was plotted against bacterioclastic activity, the relationship was found to be linear. There was no correlation, however, between bactericidal activity and hydrophobicity of derivatives. In conclusion, our findings suggest that the bactericidal activity of N-dodecylpyridinium derivatives is dependent on the electron density of the ammonium nitrogen, and also on the bacterioclastic activity.
