Incorporation of porphyrin acetylides into duplexes of the simplified nucleic acid GNA
作者:Hui Zhou、Andrew T. Johnson、Olaf Wiest、Lilu Zhang
DOI:10.1039/c0ob00439a
日期:——
A porphyrin-acetylide-modified GNA (glycol nucleic acid) phosphoramidite building block was synthesized in an economical fashion starting from (S)-glycidyl-4,4′- dimethoxytrityl ether in just 4 steps with an overall yield of 48%. The porphyrin acetylide nucleotide was incorporated into GNA duplexes opposite ethylene glycol abasic sites and the duplexes were analyzed by UV-melting, UV-vis, fluorescence spectroscopy, and circular dichroism. The modified GNA duplexes display lower thermal stabilities, however, the stabilities of the duplexes can be modulated by the incorporation of Zn2+ (further destabilization) or Ni2+ (stabilization relative to the uncomplexed porphyrin). Uncomplexed as well as Ni2+-coordinated porphyrins intercalate into the GNA duplex whereas Zn2+-coordinated porphyrins are most likely located outside the base stack. Adjacent porphyrins in opposite strands of GNA duplexes show an electronic interaction with each other which might be exploited in the future for the design of photoelectrical devices.
以(S)-缩水甘油-4,4′-二甲氧基三苯甲基醚为起点,仅用 4 个步骤就以经济的方式合成了卟啉乙酰化修饰的 GNA(乙二醇核酸)磷酰胺结构单元,总产率为 48%。卟啉乙酰核苷酸与乙二醇消旋位点相对的 GNA 双链体结合,并通过紫外熔融、紫外可见光、荧光光谱和圆二色性对双链体进行分析。经修饰的 GNA 双链体显示出较低的热稳定性,然而,双链体的稳定性可以通过加入 Zn2+(进一步脱稳)或 Ni2+(相对于未络合的卟啉稳定)来调节。未络合的卟啉和 Ni2+ 配位的卟啉会插层到 GNA 双链中,而 Zn2+ 配位的卟啉则很可能位于基叠层之外。在 GNA 双链的相对链中,相邻的卟啉之间显示出电子相互作用,这可能会被用于未来光电设备的设计。