We report here the first synthesis of 5-phenyl–telluride–thymidine derivatives and the Te-phosphoramidite. We also report here the synthesis, structure and STM current-imaging studies of DNA oligonucleotides containing the nucleobases (thymine) derivatized with 5-phenyl-telluride functionality (5-Te). Our results show that the 5-Te-DNA is stable, and that the Te-DNA duplex has the thermo-stability similar to the corresponding native duplex. The crystal structure indicates that the 5-Te-DNA duplex structure is virtually identical to the native one, and that the Te-modified T and native A interact similarly to the native T and A pair. Furthermore, while the corresponding native showed weak signals, the DNA duplex modified with electron-rich tellurium functionality showed strong topographic and current peaks by STM imaging, suggesting a potential strategy to directly image DNA without structural perturbation.
我们在此报告了 5-苯基
碲化物
胸苷衍
生物和 Te-亚
磷酰胺的首次合成。我们还在此报告了含有 5-苯基
碲化物官能团 (5-Te) 衍生的核碱基 (胸腺
嘧啶) 的 DNA 寡核苷酸的合成、结构和 STM 电流成像研究。我们的结果表明 5-Te-DNA 是稳定的,并且 Te-DNA 双链体具有与相应的天然双链体相似的热稳定性。晶体结构表明 5-Te-DNA 双链体结构实际上与天然双链体结构相同,并且 Te 修饰的 T 和天然 A 相互作用与天然 T 和 A 对类似。此外,虽然相应的天然信号显示出微弱的信号,但用富电子
碲功能修饰的 DNA 双链体通过 STM 成像显示出很强的形貌和电流峰,这表明了一种在没有结构扰动的情况下直接对 DNA 进行成像的潜在策略。