Cyclodextrin (CD) based supramolecular complexes have been prepared using a stilbene bis(β-CD) dimer and a ditopic adamantyl guest. The conformation of the stilbene bis(β-CD) dimer in aqueous solutions could be photochemically controlled. The ROESY spectra of the β-CD dimer with the adamantyl dimer showed NOE between the protons of adamantyl moieties and the inner protons of the CD. When the host cyclodextrin dimer was in trans conformation, supramolecular dimers or small assemblies are formed in solutions, whereas in its cis conformation supramolecular linear polymers with high molecular weight were observed. Thus the structure of the supramolecular polymers could be controlled by an external stimulus.

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The microscopic protonation mechanism, at an inframolecular level, of norbadione A, a pigment extracted from mushrooms and known to complex cesium cations, was determined by using 1H NMR titrations and the cluster expansion method. This study revealed a pH dependent Z to E isomer switch that occurs in both pulvinic moieties. As a consequence, norbadione A can exist in solution in four stereomeric forms (E-E, E-Z, Z-E, and Z-Z), which can be of interest in the development of molecular-level devices. In the presence of 0.15 M NaCl, the calculated microconstants showed an unusual apparent cooperativity between the enol groups, which results from the release of the sodium cations upon protonation of norbadione A.