一种苊并杂环有机小分子嵌入DNA的几何学模式研究  

Studies on the Binding Geometry of Intercalation of 4-(2-Diethylamino-ethylamino)-8-oxo-8H-acenaphtho[1,2-b]pyrrole-9-carbonitrile to DNA by Molecular Spectra

作　　者：杨源源[1] 张志超[1] 盛辉[2] 刘凤玉[1] 钱旭红[1] 徐芹[1] 张晶[1] 

机构地区：[1]大连理工大学精细化工国家重点实验室,大连116012 [2]吉林大学第一医院,长春130021

出　　处：《高等学校化学学报》2007年第3期453-457,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:30400106)资助

摘　　要：利用圆二色谱(CD)、紫外-可见吸收光谱以及荧光光谱等方法对苊并杂环化合物8-氧-8H-苊并[1,2-b]吡咯-9-腈(A1)与小牛胸腺DNA(CTDNA)的相互作用进行了研究.结果表明,随着n(A1)/n(CTDNA)的变化存在两种不同的几何学结合构型.当n(A1)/n(CTDNA)值低于0.20时,A1分子与DNA的结合方式是不均一的,化合物分子以多种角度嵌入到DNA碱基对之间.表现为A1-DNA复合物的诱导圆二色光谱图上较小的正峰和紫外吸收光谱图缺省等吸收点.DNA的特征圆二色谱图表明,在n(A1)/n(CTDNA)≤0.20范围内,CTDNA的构象从标准的B型转化为A-like型;当n(A1)/n(CTDNA)>0.20时,诱导圆二色光谱由正峰转变为强度大、波形复杂的负峰,表明A1分子开始堆积到DNA螺旋的表面,同时DNA的二级结构发生了进一步变化.The binding geometry of a heterocyclic compound, 4-（2-diethylamino-ethylamino）-8-oxo-8H-acenaphtho[ 1,2-b] pyrrole-9-carbonitrile （A1） to CT DNA was studied by using molecular spectroscopy. Deduced from SYBR Green-DNA melt curve, fluorescence spectroscopy, UV-Vis spectroscopy and circular dichroism（CD）, there were two different interaction mechanisms involved in the whole interaction process depending on the the molar ratios of A1 to CT DNA base pairs. The binding geometry of A1 to CT DNA was investigated by the induced CD spectroscopy based on the different n （ A1 ）/n （ CT DNA） ratio. The value n （ A1 ）/n （ CT DNA） = 0. 20 was the turning point; when n （ A1 ）/n （ CT DNA） ≤ 0. 20, the intercalation orientation of A1 to the dyad axis of DNA double helix was heterogeneous and stacking of A1 on the surface helix of DNA was available when n（A1）/n（CT DNA） 〉020.

关 键 词：嵌入剂 几何学构型 DNA构象 圆二色谱 

分 类 号：O657[理学—分析化学] Q523.4[理学—化学]