School of Chemistry and Biochemistry, NCCR Chemical Biology , University of Geneva , CH-1211 Geneva , Switzerland.
J Am Chem Soc. 2019 Jan 16;141(2):810-814. doi: 10.1021/jacs.8b12554. Epub 2019 Jan 8.
In this Communication, we introduce transmembrane anion transport with pnictogen-bonding compounds and compare their characteristics with chalcogen- and halogen-bonding analogues. Tellurium-centered chalcogen bonds are at least as active as antimony-centered pnictogen bonds, whereas iodine-centered halogen bonds are 3 orders of magnitude less active. Irregular voltage-dependent single-channel currents, high gating charges, and efficient dye leakage support for the formation of bulky, membrane-disruptive supramolecular amphiphiles due to "too strong" binding of anions to tris(perfluorophenyl)stibanes. In contrast, the chalcogen-bonding bis(perfluorophenyl)tellanes do not cause leakage and excel as carriers with nanomolar activity, with P = 10.4 for anion/cation selectivity and P = 4.5 for anion selectivity. The selectivities are lower with pnictogen-bonding carriers because their membrane-disturbing 3D structure also affects weaker binders ( P = 2.1, P = 2.5). Their 2D structure, directionality, hydrophobicity, and support from proximal anion-π interactions are suggested to contribute to the unique power of chalcogen bonds to transport anions across lipid bilayer membranes.
在本通讯中，我们介绍了具有磷键合化合物的跨膜阴离子转运，并将其特性与硫属和卤键合类似物进行了比较。碲中心的硫属键至少与锑中心的磷键一样活跃，而碘中心的卤键的活性则低 3 个数量级。不规则的电压依赖性单通道电流、高门控电荷和有效的染料泄漏表明，由于阴离子与三(全氟苯基)锑烷的“结合太强”，形成了体积庞大、破坏膜的超分子两亲体。相比之下，硫属键联的双(全氟苯基)碲烷不会引起泄漏，并且作为载流子具有纳摩尔级的活性，其阴离子/阳离子选择性为 P = 10.4，阴离子选择性为 P = 4.5。磷键合载体的选择性较低，是因为它们破坏膜的 3D 结构也会影响较弱的配体（P = 2.1，P = 2.5）。它们的 2D 结构、方向性、疏水性以及与近端阴离子-π 相互作用的支持被认为有助于硫属键将阴离子跨脂质双层膜转运的独特能力。
