Optical, Redox, and DNA-Binding Properties of Phenanthridinium Chromophores: Elucidating the Role of the Phenyl Substituent for Fluorescence Enhancement of Ethidium in the Presence of DNA
作者:Christa Prunkl、Markus Pichlmaier、Rainer Winter、Vladimir Kharlanov、Wolfgang Rettig、Hans-Achim Wagenknecht
DOI:10.1002/chem.200902823
日期:2010.3.15
pairs of chromophores. The first pair, consisting of 1 and 2, lacks the amino groups in positions 3 and 8, and, as a result, these dyes exhibit clearly altered optical and electrochemical properties compared with E. In the presence of DNA, a significant fluorescence quenching was observed. Their binding affinity to DNA is reduced by nearly one order of magnitude. The electronic effect of the phenyl group
菲啶基团发色团5-乙基-6-苯基菲基吡啶鎓(1),5-乙基-6-甲基菲基吡啶鎓(2),3,8-二氨基-5-乙基-6-甲基菲啶鎓(3)和3,8-二氨基菲啶鎓乙基-6(4- N,N-二乙基氨基苯基)菲啶鎓(4)的特征在于其光学和氧化还原特性。所有染料均用于具有随机序列的17mer DNA双链体的滴定实验中,并确定了它们的结合亲和力。将结果与著名的溴化乙锭(E)进行比较。通常,这组数据允许3、6和8位上的取代基对E的光学性质产生影响要阐明。尤其是,化合物4用于比较E位置6处的苯基取代基的弱供电子特性与供电子较多的4 N,N-二乙基氨基苯基。对所有测量值的分析揭示了两对生色团。第一对由1和2组成,在3和8位上缺少氨基,因此,与E相比,这些染料具有明显改变的光学和电化学性质。在DNA存在下,观察到明显的荧光猝灭。它们与DNA的结合亲和力降低了近一个数量级。第6位上的苯基对这类染料的电子效应很小。第二