Synthesis and Electrochemical Evaluation of Conjugates between 2′-Deoxyadenosine and Modified Anthraquinone: Probes for Hole-Transfer Studies in DNA
作者:Reham A. I. Abou-Elkhair、Dabney W. Dixon、Thomas L. Netzel
DOI:10.1021/jo900306g
日期:2009.7.3
Photoexcitation of anthraquinones (AQ) in association with DNA results in DNA damage mainly at guanine residues, with products from thymine oxidation also observed. Studies of adenine oxidation will be aided by systems with an increased driving force for charge transfer, achieved by adding electron-withdrawing groups to the AQ ring. Attaching AQ derivatives to adenine via a bridge with two carbon atoms should enable
蒽醌(AQ)与DNA的光激发导致DNA损伤主要在鸟嘌呤残基,并且还观察到胸腺嘧啶氧化的产物。腺嘌呤氧化的研究将通过在AQ环上添加吸电子基团而实现的,具有增强的电荷转移驱动力的系统来辅助。通过带有两个碳原子的桥将AQ衍生物连接到腺嘌呤上,应该能够在DNA双链体结构内实现预期的区域控制。本文中,我们报道了AQ和腺嘌呤之间共轭物的合成,其中AQ部分已被甲酰基,三氟乙酰基和两个甲基酯基团修饰。这些已经通过钯偶联合成叔-丁基二苯基甲硅烷基5'-保护的8-乙炔基-2'-脱氧腺苷与相应的溴蒽醌中间体。通过2,6-二溴蒽醌的单锂化制备带有甲酰基或三氟乙酰基的溴中间体,该步骤需要保护蒽醌羰基。通过用4-溴苯甲酰氯进行Friedel-Crafts酰化反应,然后氧化成三羧酸,环化形成蒽醌环,最后酯化,从1,2,4-三甲基苯中获得带有两个甲酯基的溴中间体。乙炔基连接基的氢化得到乙炔基连接基。循环伏安法表明,具有两