Exploring the Binding Ability of Polyammonium Hosts for Anionic Substrates: Selective Size-Dependent Recognition of Different Phosphate Anions by Bis-macrocyclic Receptors
作者:Carla Bazzicalupi、Andrea Bencini、Claudia Giorgi、Barbara Valtancoli、Vito Lippolis、Alessandro Perra
DOI:10.1021/ic2007815
日期:2011.8
6-dimethylenepyridine (L2), or a 2,3-dimethylenequinoxaline (L3) spacer, has been studied by means of potentiometric titrations, 1H and 31P NMR measurements in aqueous solutions, and molecular modeling calculations. In the case of inorganic phosphates, the binding properties of the receptors appear to be determined by their geometrical features, in particular the distance between the two [9]aneN3 units
单磷酸,二磷酸和三磷酸,二磷酸腺苷(ADP)和三磷酸腺苷酶(ATP)与受体L1-L3的结合,后者由两个[9] aneN 3单元组成,并被2,9-二亚甲基-1,10隔开-邻菲咯啉(L1),2,6-二亚甲基吡啶(L2)或2,3-二亚甲基喹喔啉(L3)间隔基已通过电位滴定,水溶液中的1 H和31 P NMR测量以及分子建模计算。在无机磷酸盐的情况下,受体的结合特性似乎取决于它们的几何特征,特别是两个[9] aneN 3之间的距离由间隔子强加的两个大环单元分开的单元。虽然L1能够选择性地结合二磷酸和单磷酸三磷酸酯,但L3选择性地配位较小的单磷酸根阴离子。最后,L2显示二磷酸的优先结合。1 H和31P NMR测量表明,该复合物基本上是通过阴离子与受体大环亚基的质子化胺基之间的电荷-电荷和氢键相互作用而稳定的。分子动力学模拟表明,L1的两个大环单元之间的距离较大,可使该受体与三磷酸酯形成更多的氢键接触