Department of Chemistry, University of Puerto Rico, Rio Piedras Campus, Rio Piedras, Puerto Rico 00931.
J Am Chem Soc. 2009 Mar 11;131(9):3186-8. doi: 10.1021/ja809612d.
Here we show the reversible high fidelity switching between two discrete self-assembled supramolecules made from a lipophilic 8-phenyl-2'-deoxyguanosine derivative induced by an indirect solvent effect. A hexadecameric supramolecule containing four stacked tetramers is formed in acetonitrile aided by higher potassium concentrations. When the amount of weakly solvated potassium decreases, due the lower activity of potassium iodide in chloroform, an octamer is formed after the dissociation of the two outer tetramers in the hexadecamer. The switching process results from an unprecedented subtle interplay between the activity of potassium iodide and the steric crowding within the self-assembled structure. Besides the possible applications in nanoconstruction, this phenomenon sheds light into the mechanism of formation of self-assembled supramolecules made from guanosine derivatives.
在这里，我们展示了一种由疏水分子 8-苯基-2'-脱氧鸟苷衍生物诱导的间接溶剂效应，在两种离散自组装超分子之间进行的可逆高保真切换。在较高的钾浓度辅助下，在乙腈中形成包含四个堆叠四聚体的十六聚体超分子。当较弱溶剂化的钾量减少时，由于碘化钾在氯仿中的活性较低，在十六聚体的两个外四聚体解离后形成八聚体。这种开关过程源自碘化钾的活性和自组装结构内部的空间位阻之间前所未有的微妙相互作用。除了在纳米构建中的可能应用外，这种现象还揭示了由鸟苷衍生物形成自组装超分子的机制。
