Using an aryl phenanthroimidazole moiety as a conjugated flexible intercalator to improve the hybridization efficiency of a triplex-forming oligonucleotide
作者:Amany M.A. Osman、Per T. Jørgensen、Niels Bomholt、Erik B. Pedersen
DOI:10.1016/j.bmc.2008.10.037
日期:2008.12
containing the intercalator X show higher thermal triplex stability than DNA-strands containing the intercalator Y. The difference can be explained by a lower degree of planarity of the intercalator in the case of naphthyl. It was also observed that triplex stability was considerably reduced when the intercalators X or Y was replaced by 2-(naphthlen-1-yl)imidazole. This confirms intercalation as the important
当将2-苯基或2-萘-1-基-菲基咪唑嵌入剂(分别为X和Y)凸起插入形成三链体的寡核苷酸中时,两种嵌入剂均显示出相应的Hoogsteen型三链体和Hoogsteen型平行链具有极高的热稳定性。对Hoogsteen错配具有高度歧视性的双工。分子建模显示,苯基或萘环与TFO中的核碱基堆叠,而菲并咪唑部分与dsDNA的碱基对堆叠。包含嵌入剂X的DNA链比包含嵌入剂Y的DNA链显示出更高的热三链稳定性。差异可以解释为在萘基情况下嵌入剂的平面度较低。还观察到,当用2-(萘-1-基)咪唑代替嵌入剂X或Y时,三链体的稳定性大大降低。这证实了插入是三重态稳定的重要因素,并且排除了质子化的咪唑与两个磷酸基团的另一种络合。通过9,10-菲醌(4)与(S)-4-(2-(2,2-二甲基-1,3-二氧戊环-4-基)的缩合反应获得插入核酸单体X和Y。乙氧基)苯甲醛(3a)或(S)-4-(2-(2,2-二甲基-1,3-