Department of Physical Chemistry and Electrochemistry, Faculty of Chemistry, Jagiellonian University, ul. R. Ingardena 3, 30-060 Krakow, Poland.
J Phys Chem B. 2010 Aug 19;114(32):10427-35. doi: 10.1021/jp102471c.
The two new p-tert-butylcalix[4]arene derivatives described here bear one or two nalidixic acid arms linked to the lower calixarene rim via the quinolone carboxylate moiety. These derivatives were synthesized in order to investigate two important features of molecules conceived as potential antibiotics, namely, metal cation complexation and interfacial properties, and the way in which they interrelate. The properties of the calixarene derivatives were studied in monomolecular films spread on pure water and on aqueous subphases containing biologically relevant mono- and divalent metal cations. These systems were examined via surface pressure and surface electrical potential measurements, polarization modulation infrared reflection absorption spectroscopy, and molecular modeling. Molecular modeling shows that important differences exist, first, between the structure and stability of the complexes formed with the two derivatives and, second, between their mono- and dication complexes. Correlating the properties of the monolayers with those of the modeled molecules lets us propose that the derivatives bearing one or two nalidixic pending arms form preferentially inter- and intramolecular complexes, respectively. The results obtained in this study indicate that a possible biological role of the nalidixic arms grafted on the calixarene crown may be revealed upon cation complexation.
这里描述的两个新的对叔丁基杯[4]芳烃衍生物在较低的杯芳烃边缘通过喹诺酮羧酸部分连接一个或两个萘啶酸臂。这些衍生物的合成目的是研究作为潜在抗生素的分子的两个重要特征，即金属阳离子络合和界面性质，以及它们相互关联的方式。通过在纯水和含有生物相关的单价和二价金属阳离子的水亚相中展开的单分子膜研究杯芳烃衍生物的性质。通过表面压力和表面电势测量、偏振调制红外反射吸收光谱和分子建模对这些系统进行了研究。分子建模表明，首先，两种衍生物形成的配合物的结构和稳定性之间存在重要差异，其次，它们的一价和二价配合物之间也存在差异。将单层的性质与建模分子的性质相关联，使我们能够提出，分别带有一个或两个萘啶酸悬垂臂的衍生物优先形成分子间和分子内配合物。本研究的结果表明，接枝在杯芳烃冠上的萘啶酸臂的可能生物学作用可能在阳离子络合时显现出来。
