Phenanthroline-containing macrocycles as multifunctional receptors for nucleotide anions. A thermodynamic and NMR study †
作者:Carla Bazzicalupi、Alessia Beconcini、Andrea Bencini、Vieri Fusi、Claudia Giorgi、Andrea Masotti、Barbara Valtancoli
DOI:10.1039/a903059j
日期:——
multifunctional receptors for the nucleotide anions at neutral or slight acidic pHs, giving 1∶1 complexes. Charge–charge and hydrogen bonding interactions take place between the polyphosphate chain of nucleotides and the polyammonium groups of L1 and L2, while the adenine moiety gives charge–dipole interactions with the ammonium groups and π-stacking with the phenanthroline unit of the receptors. The high
据报道含菲咯啉的大环2,6,10,14-四氮杂[15](2,9)环(1,10)菲咯啉(L1)的合成。L1包含连接菲咯啉单元的2,9-位的四胺链。L1的质子化已通过电位法,1 H和13 C NMR技术进行了研究,从而可以确定碱度常数和逐步质子化位点。比较了L1的质子化特征与大环2,5,8,11-四氮杂[12](2,9)环菲咯啉烷(L2)的质子化特征,其中胺基通过烯键连接。考虑[H 4 L1] 4+和[H 4 L2] 4+物种,酸性质子位于脂肪族氮上,而菲咯啉不参与质子化。二磷酸,三磷酸,ATP和ADP的结合已通过电位法和1 H和31 P NMR进行了研究。L1和L2均在中性或弱酸性pH值下均充当核苷酸阴离子的多功能受体,从而形成1∶1的络合物。核苷酸的聚磷酸酯链与L1和L2的聚铵基团之间发生电荷-电荷和氢键相互作用,而腺嘌呤部分与铵基团形成电荷-偶极相互作用,并与受体的菲咯啉单元形成π堆积。