作者:Ryan E. Dawson、Andreas Hennig、Dominik P. Weimann、Daniel Emery、Velayutham Ravikumar、Javier Montenegro、Toshihide Takeuchi、Sandro Gabutti、Marcel Mayor、Jiri Mareda、Christoph A. Schalley、Stefan Matile
DOI:10.1038/nchem.657
日期:2010.7
Attractive in theory and confirmed to exist, anionâÏ interactions have never really been seen at work. To catch them in action, we prepared a collection of monomeric, cyclic and rod-shaped naphthalenediimide transporters. Their ability to exert anionâÏ interactions was demonstrated by electrospray tandem mass spectrometry in combination with theoretical calculations. To relate this structural evidence to transport activity in bilayer membranes, affinity and selectivity sequences were recorded. Ï-acidification and active-site decrowding increased binding, transport and chloride > bromide > iodide selectivity, and supramolecular organization inverted acetate > nitrate to nitrate > acetate selectivity. We conclude that anionâÏ interactions on monomeric surfaces are ideal for chloride recognition, whereas their supramolecular enhancement by Ï,Ï-interactions appears perfect to target nitrate. Chloride transporters are relevant to treat channelopathies, and nitrate sensors to monitor cellular signaling and cardiovascular diseases. A big impact on organocatalysis can be expected from the stabilization of anionic transition states on chiral Ï-acidic surfaces. For quadrupole moments up to +39 Buckinghams, increasing Ï-acidity of aromatic surfaces is shown to cause tighter anion binding in tandem mass spectrometry experiments, higher binding energies in molecular models, stronger charge-transfer absorption bands, and increasingly effective and selective anion transport across lipid-bilayer membranes.
阴离子与萘的相互作用在理论上很有吸引力,而且已被证实存在,但人们从未真正看到过这种作用。为了捕捉它们的行动,我们制备了一系列单体、环状和棒状的萘二亚胺转运体。通过电喷雾串联质谱法和理论计算,证明了它们能够发挥阴离子与萘二亚胺的相互作用。为了将这一结构证据与双层膜中的转运活性联系起来,我们记录了亲和性和选择性序列。阴离子的酸化和活性位点的拥挤增加了结合、运输和氯化物>溴化物>碘化物的选择性,而超分子结构则将醋酸盐>硝酸盐倒置为硝酸盐>醋酸盐的选择性。我们的结论是,单体表面的阴离子Ï相互作用是氯化物识别的理想选择,而通过Ï,Ï-相互作用增强的超分子作用则是针对硝酸盐的完美选择。氯化物转运体可用于治疗通道疾病,硝酸盐传感器可用于监测细胞信号传导和心血管疾病。阴离子过渡态在手性Ï酸性表面上的稳定化可望对有机催化产生重大影响。对于高达 +39 白金汉的四极矩,芳香表面的Ï-酸度增加会导致串联质谱实验中阴离子结合更紧密、分子模型中的结合能更高、电荷转移吸收带更强、阴离子跨脂质层膜传输的有效性和选择性更高。