Bambusurils (BUs) are known to be rigid cavitands that feature an extended, jigger‐like conformation, and the BU[6]s strongly bind anions within their hydrophobic cavity. These features are not necessarily shared by the family of perthio‐BUs. This study reveals that perthio‐BUs assume a compact conformation and perthio‐BU[6]s are poor anion binders, crystallizing as anion‐free species from solutions containing halide salts. Computational studies show that the equatorial sulfur atoms compete against guest anions for binding with the glycoluril methine groups via strong van der Waals (vdW) attractive interactions. These competitive contacts not only account for the diminished anion‐binding of perthio‐BUs, but also explain their compact conformation. The semithio‐ and perthio‐BU[4]s form linear coordination polymers with HgII in the solid‐state regardless of their intrinsic molecular conformation. The strong involvement of sulfur atoms in intramolecular interactions differentiates the equatorial from the axial (peripheral) heteroatoms, thus offering chemoselective and regioselective transformations.

This review describes the synthetic and medicinal chemistry of small molecule modulators of the voltage-gated Kv7 (KCNQ) potassium channels and the available data of their biological and clinical properties.

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This study confirms the hypothesis that bambusurils (BUs) with equatorial sulfur atoms cannot assume an anion-binding jigger conformation due to strong intramolecular van der Waals attractive interactions. NMR, X-ray crystallography, and computation with newly synthesized eq-semithio-BU­[4] and ax-semiaza-eq-semithio-BU­[4]­s indicate that they all assume compact conformations. Intramolecular distances and a torsional angle serve as reliable indicators of the conformation of any BU. Chemoselective alkylation at the peripheral (equatorial) thiourea functions provides a convenient entry to novel hetero-BUs.