【摘要】 利用紫外、红外和荧光光谱法研究DNA碱基胸腺嘧啶与蒽的相互作用以及由此引起的胸腺嘧啶结构变化.荧光猝灭实验测得二者的结合常数为9.6×103L·mol-1;紫外差谱结果显示,蒽与胸腺嘧啶的作用对共轭系统的π-π*跃迁产生了影响;蒽与胸腺嘧啶混合物的红外光谱显示胸腺嘧啶的N—H和CO振动峰以及环的面外变形振动峰均发生位移,表明二者之间可能以面对面相平行的方式发生了π-π电子给体受体作用,作用结果导致胸腺嘧啶环上电子云密度增大.更多还原

【Abstract】 The interaction of anthracene with thymine, a base only existing in DNA, was studied by using the methods of fluorescence quenching, UV absorption spectra and IR spectra. As a result, a linear Stern-Volmer plot was obtained from fluorescence quenching and the binding constant was calculated as 9.6×103 L·mol-1. From the UV difference spectra, it was understood that the π-π transition was disturbed by the interaction between anthracene and thymine in the conjugated system, and from the IR spectra of the mixture, it was noticed that the peak position with respect to pure thymine shifted at the absorption bands of N—H, CO and the out-plane deformation bands of the ring. It could thus be concluded from these results that charge transfer interaction of face-to-face geometry occurred between the two π systems, and this eventually brought about an increase of the electron cloud density of thymine.更多还原