homopurine-homopyrimidine sequence. To develop novel nucleoside analogues which recognize CG interruption in homopurine-homopyrimidine dsDNA, we synthesized a novel 2'-O,4'-C-methyleneribonucleic acid (2'-O,4'-C-methylene bridged nucleic acid; 2',4'-BNA) that bears the unnatural nucleobases, 2-pyridone (PB) or its 5-methyl congener (mPB); these analogues were introduced into pyrimidine TFOs using a DNA synthesizer
可以被三链体形成寡核苷酸(TFO)识别的双链DNA(dsDNA)的序列限于高
嘌呤-高
嘧啶序列。为了开发可识别高
嘌呤-高
嘧啶dsDNA中CG中断的新型核苷类似物,我们合成了新型2'-O,4'-C-亚甲基
核糖核酸(2'-O,4'-C-亚甲基桥接的核酸; 2', 4'-BNA)带有非天然核碱基2-
吡啶酮(PB)或其5-甲基同源物(mPB);使用DNA合成仪将这些类似物引入
嘧啶TFO。还合成了具有2'-脱氧-β-D-
呋喃呋喃糖基-2-
吡啶酮(P)或2',4'-BNA碱性单体(HB)的TFO。各种合成的15-mer TFO和相应的高
嘌呤-高
嘧啶dsDNA的三链体形成能力,在紫外熔融实验中检查了含有一个
嘧啶-
嘌呤(PyPu)中断的化合物。发现在生理条件下(7 mM
磷酸钠,140 mM KCl,5 mM
精胺,pH 7.0),TFO中的PB和mPB成功识别了CG中断。此外,还证实了在包含三个CG中断的ds