Lights and shadows in the challenge of binding acyclovir, a synthetic purine-like nucleoside with antiviral activity, at an apical–distal coordination site in copper(II)-polyamine chelates
作者:Inmaculada Pérez-Toro、Alicia Domínguez-Martín、Duane Choquesillo-Lazarte、Esther Vílchez-Rodríguez、Josefa María González-Pérez、Alfonso Castiñeiras、Juan Niclós-Gutiérrez
DOI:10.1016/j.jinorgbio.2015.03.006
日期:2015.7
acid interactions becomes essential to understand these biological processes. In this work, the synthetic purine-like nucleoside acyclovir (acv) has been used as a model of guanosine recognition with copper(II)-polyamine chelates. The chemical stability of the N9-acyclic arm in acv offers the possibility to use this antiviral drug to deepen the knowledge of metal–nucleoside interactions. Cu(II) chelates
Entropy contribution to the relative solution stability of copper(III) and nickel(III) tetraazamacrocyclic complexes in aqueous perchloric acid
作者:Giancarlo De Santis、Luigi Fabbrizzi、Maurizio Licchelli、Piersandro Pallavicini
DOI:10.1039/dt9910002925
日期:——
changes determined. The potential difference, ECu–ENi, which is related to the metathetic equilibrium [CuIIIL]3++[NiIIL]2+⇌[CuIIL]2++[NiIIIL]3+, becomes less positive with increasing HClO4 concentration, indicating a stabilizing effect on the copper(III) complex, compared to NiIII. This effects is related to the competition by the ions of the electrolyte for the water molecules co-ordinated to the electroactive
包含等摩尔量的不同浓度HClO 4([Ni II(cyclam)] [ClO 4 ] 2和[Cu II(cyclam)] [ClO 4 ] 2(cyclam = 1,4,8,11-四氮杂环十四烷)的溶液通过伏安法研究了4–11.56 mol dm –3),并确定了与Ni II –Ni III和Cu II –Cu III氧化还原变化有关的电势。电位差E Cu – E Ni与复分解平衡有关[Cu III L]3+ + [Ni II L] 2+ + [Cu II L] 2+ + [Ni III L] 3+,随着HClO 4浓度的增加,正值变小,表明与铜( III)配合物相比有稳定作用镍三。该效应与电解质的离子竞争与电活性物质配位的水分子的竞争有关。熵变Δ小号⊖与复分解平衡相关联的通过伏安调查确定在不同的温度(-15至+ 40℃)进行。在Δ的基础上小号⊖值表明,在HClO 4浓度低于8 mol dm
Heterogeneous and Homogeneous Routes in Water Oxidation Catalysis Starting from Cu<sup>II</sup>
Complexes with Tetraaza Macrocyclic Ligands
oxidation. In this study, we investigate the electrochemical activity of copper(II) complexes with two tetraaza macrocyclic ligands, distinguishing heterogeneous or homogeneous processes depending on the reaction media. In an alkaline aqueous solution, and upon application of an anodic bias to working electrodes, an active copper oxide layer is observed to electrodeposit at the electrode surface. Conversely