The synthesis and supramolecular properties of the first methylene-bridged propanediurea-based dimers are described. These dimers, bearing an aromatic sidewall, have the shape of molecular clips. Unlike glycoluril-based dimers, these clips neither dimerize nor accept any organic guests, due to their small cavities. Both propanediurea- and glycoluril-based dimers bind halide anions on the convex side of the molecules, even in highly polar organic solvents. This observation brings new insights into the mechanism of cucurbituril formation.

Abstract Neutral and negatively charged anion receptors functioning in pure water are rare in supramolecular chemistry. Moreover, studies on adjusting the affinity of such receptors toward anions i...

Driving forces of anion binding in water in contrast to nonpolar environments are of high interest because of their relevance to biology and medicine. Here we report a neutral bambusuril macrocycle (1), soluble in both water and nonpolar solvents due to decoration with 12 polyethylene glycol-based substituents. The new bambusuril has the highest affinity for I– in pure water ever reported for a synthetic macrocycle relying on hydrogen bonding interactions rather than metal coordination or...

The phylogenies of allopolyploids take the shape of networks and cannot be adequately represented as bifurcating trees. Especially for high-polyploids (i.e., organisms with more than six sets of nuclear chromosomes), the signatures of gene homoeolog loss, deep coalescence and polyploidy may become confounded, with the result that gene trees may be congruent with more than one species network. Herein, we obtained the most parsimonious species network by objective comparison of competing scenarios involving polyploidization and...

Stenophagy (narrow diet breadth) represents an extreme of trophic specialization in carnivores, but little is known about the forces driving its evolution. We used spiders, the most diversified group of terrestrial predators, to investigate whether stenophagy 1) promoted diversification, 2) was phylogenetically conserved and evolutionarily derived state, and 3) was determined either by geographical distribution and foraging guild. We utilized published data on the prey of almost 600 species. Six categories of stenophagy were found:...