Exploring the Binding Ability of Phenanthroline-Based Polyammonium Receptors for Anions: Hints for Design of Selective Chemosensors for Nucleotides
作者:Carla Bazzicalupi、Andrea Bencini、Silvia Biagini、Enrico Faggi、Stefano Meini、Claudia Giorgi、Alessio Spepi、Barbara Valtancoli
DOI:10.1021/jo901423m
日期:2009.10.2
The synthesis of receptor 2,6,10,14,18-pentaaza[20]-21,34-phenanthrolinophane (L1), containing a pentaamine chain linking the 2,9 positions of a phenanthroline unit, is reported. The protonation features of L1 and of receptor 2,6,10,14,18,22-hexaaza[23]-24,37-phenanthrolinophane (L2) have been studied by means of potentiometric, 1H NMR, and spectrofluorimetric measurements; this study points out that
据报道,受体2,6,10,14,18-戊杂[20] -21,34-菲咯啉烷(L1)的合成,其含有连接菲咯啉单元2,9位的五胺链。通过电位,1 H NMR和荧光光谱法研究了L1和2,6,10,14,18,22-六氮杂[23] -24,37-菲咯啉烷(L2)的质子化特征。这项研究指出,两种受体的荧光发射都取决于多胺链的质子化状态。实际上,这些受体仅在中性或酸性pH值(所有脂肪族胺基均质子化)下才发射。电位滴定表明,L2能够与TTP,CTP和GTP选择性结合ATP。在L1的情况下,这种选择性丧失了。1 H和31P NMR测量和分子力学计算表明,核苷酸的磷酸酯链与质子化受体的铵基团产生强的静电和氢键相互作用,而核碱基则通过与菲咯啉的π堆积或与铵基团的氢键相互作用。值得注意的是,MM计算表明所有核苷酸都以包容性方式相互作用。实际上,在所有加合物中,磷酸酯链被封闭在受体腔内。[[H 6 L2)2(TTP)2(H