Dabrowa Kajetan, Ulatowski Filip, Lichosyt Dawid, Jurczak Janusz
Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
Org Biomol Chem. 2017 Jul 19;15(28):5927-5943. doi: 10.1039/c7ob01385j.
The binding selectivity of structurally simple anion receptors is governed by the Hofmeister series (SO > HPO > carboxylates ∼ HPO > HCO > Cl), and exceptions to this rule are rare and require utilization of structurally sophisticated receptors. In this paper we examined a set of 48 structurally diverse anion receptors, barely one fourth of which exhibit selectivity for chloride over more basic dihydrogen phosphate (HPO) or carboxylates (MeCO and PhCO). Searching for regularities in the properties of these mainly macrocyclic-derived receptors across quite systematic changes in structure, combined with analysis of multiple crystal structures, allowed us to identify the crucial structural features that are likely required for the occurrence of the phenomenon of selective chloride binding. Examination of a subset of other 'case study' receptors reported in the literature as being particularly chloride-selective served as a confirmation of our hypotheses. As such, our findings are valid for all artificial receptors with exceptional selectivity for chloride, as well as for natural chloride channel proteins (ClC).
结构简单的阴离子受体的结合选择性受霍夫迈斯特序列（SO＞HPO＞羧酸盐～HPO＞HCO＞Cl）支配，该规则的例外情况很少见，需要使用结构复杂的受体。在本文中，我们研究了一组48种结构多样的阴离子受体，其中只有四分之一对氯离子的选择性高于碱性更强的磷酸二氢根（HPO）或羧酸盐（MeCO和PhCO）。通过在结构上进行相当系统的变化来寻找这些主要由大环衍生的受体的性质规律，并结合对多个晶体结构的分析，我们能够确定选择性氯离子结合现象发生可能所需的关键结构特征。对文献中报道的其他特别具有氯离子选择性的“案例研究”受体子集的研究证实了我们的假设。因此，我们的发现对所有对氯离子具有特殊选择性的人工受体以及天然氯离子通道蛋白（ClC）均有效。
