Dudev Todor, Cheshmedzhieva Diana, Dimitrova Radoslava, Dorkov Peter, Pantcheva Ivayla
Laboratory of Computational Chemistry and Spectroscopy, Faculty of Chemistry and Pharmacy, "St. Kl. Ohridski" University of Sofia 1, J. Bourchier Blvd. 1164 Sofia Bulgaria
Laboratory of Biocoordination and Bioanalytical Chemistry, Faculty of Chemistry and Pharmacy, "St. Kl. Ohridski" University of Sofia 1, J. Bourchier Blvd. 1164 Sofia Bulgaria
RSC Adv. 2020 Feb 4;10(10):5734-5741. doi: 10.1039/c9ra09784h.
The affinity of monensin A to bind monovalent metal cations was evaluated by means of density functional theory (DFT) combined with polarizable continuum model (PCM) computations. The effect of various factors on complex formation between the monensinate A anion and group IA and IB metal ions was assessed. Competition between Na taken as a reference and monovalent metal cations was estimated using the Gibbs free energy for substituting the ligand-bound Na with its rival ions in the process [M-solution] + [MonNa] → [MonM] + [Na-solution] (M = Li, K, Rb, Cs, Cu, Ag and Au). The calculations revealed that the decrease in size of the cations accompanied by an increase of their accepting ability enhances the metal selectivity towards ligand donor atoms. In the gas-phase the affinity of monensinate A decreases in the order Cu > Li > Na > Au > Ag > K > Rb > Cs. The complex formation can be manipulated by changing the solvent used. The polyether ionophore selectively binds Na ions in polar solvents but could become Li or Cu-selective in low-polarity solvents.
通过密度泛函理论（DFT）结合极化连续介质模型（PCM）计算，评估了莫能菌素A与单价金属阳离子结合的亲和力。评估了各种因素对莫能菌素A阴离子与IA族和IB族金属离子之间形成配合物的影响。以Na作为参考，通过吉布斯自由能估算了单价金属阳离子之间的竞争，该吉布斯自由能用于在[M-溶液] + [MonNa] → [MonM] + [Na-溶液]过程中用其竞争离子取代与配体结合的Na（M = Li、K、Rb、Cs、Cu、Ag和Au）。计算结果表明，阳离子尺寸的减小伴随着其接受能力的增强，提高了对配体供体原子的金属选择性。在气相中，莫能菌素A的亲和力按Cu > Li > Na > Au > Ag > K > Rb > Cs的顺序降低。可以通过改变所用溶剂来控制配合物的形成。聚醚离子载体在极性溶剂中选择性结合Na离子，但在低极性溶剂中可能变为Li或Cu选择性。
