Cover Picture: Three-Component Cucurbit[6]uril Framework with 1:2 Host-Guest Motif and Dimeric Boric Acid (Chin. J. Chem. 5/2012)

The cover picture shows a versatile approach combining different recognition modes to the construction of multicomponent complex supramolecular architectures. Recognition and assembly of macrocyclic host molecules are fundamental and crucial in the field of supramolecular research. Three-component cucurbit[6]uril framework with 1:2 host-guest motif and dimeric boric acid has been constructed. The 1:2 host-guest motif demonstrates both cation binding of imidazolium moiety and anion binding of sulfonate moiety for the first time. Incorporation of dimeric boric acid facilitates the formation of metal-free three-dimensional framework. More details are discussed in the article by Liu et al. on page 1022–1026.