Zegar I, Gräslund A, Bergman J, Eriksson M, Nordén B
Department of Biophysics, University of Stockholm, Sweden.
Chem Biol Interact. 1989;72(3):277-93. doi: 10.1016/0009-2797(89)90004-5.
The non-covalent DNA interaction of the anticancer drug ellipticine (Scheme I, 1a) as well as an indolo[2,3-b]-quinoxaline derivative (Scheme I, 3b) with a dimethylaminoethyl side chain has been studied by light absorption, linear dichroism (LD) and fluorescence. Compound 3b (Scheme I) has antitumorigenic as well as antiviral activity. Both compounds bind to DNA or synthetic polynucleotides such as poly(dA-dT).(dA-dT) and poly(dG-dC).(dG-dC) by intercalation. In contrast to ellipticine, compound 3b (Scheme I) exhibits a significant binding specificity for alternating AT sequences. Its fluorescence is strongly enhanced in AT sequences and quenched in GC sequences. Fluorescence titrations evaluated as Scatchard plots show that both ellipticine and compound 3b (Scheme I) bind to the nucleic acids according to a non-cooperative neighbor exclusion model.
通过光吸收、线性二色性（LD）和荧光研究了抗癌药物玫瑰树碱（方案I，1a）以及具有二甲基氨基乙基侧链的吲哚并[2,3 - b] - 喹喔啉衍生物（方案I，3b）与DNA的非共价相互作用。化合物3b（方案I）具有抗肿瘤和抗病毒活性。这两种化合物都通过嵌入作用与DNA或合成多核苷酸如聚（dA - dT）·（dA - dT）和聚（dG - dC）·（dG - dC）结合。与玫瑰树碱不同，化合物3b（方案I）对交替的AT序列表现出显著的结合特异性。其荧光在AT序列中强烈增强，而在GC序列中淬灭。以Scatchard图评估的荧光滴定表明，玫瑰树碱和化合物3b（方案I）均根据非协同邻位排斥模型与核酸结合。
