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The self-assembly process of a supramolecular edifice based on the coordination of europium(III) by a ditopic strand L bearing tridentate bis(benzimidazolyl)pyridine subunits is reported. The thermodynamic and kinetic data allow the prediction of the apparent 'magic' self-assembly by Eu2L3, which is fast and efficient only under a strict set of conditions.

The synthesis, structural characteristics, and coordination properties of a family of three triple-stranded, polytopic ligands were analyzed. Classical measurements was utilized in examining the consequences of the structural changes on the binders' coordination properties and allosteric effects. Results have shown that subtle structural changes have an effect on the binding properties of the compounds.

The importance of both topological and geometrical effects in the knotted structure and interactions of dicopper(I) cations on the demetalation rates and mechanism was determined through single-wavelength and multiwavelength absorption spectrophotometry. Results have shown that the knotted topology radically augments the dicopper interactions. It was also demonstrated that following the release of the first copper (I) cation, a rearrangement in the molecular structure occurs secondary to the entangled nature of the trefoil knots.

A spectroscopic study probes into the photophysical and complexation behavior of a new macrotricyclic bisanthracenyl receptor. Apart from monomer-derived signals, the receptor exhibits excimer type fluorescence due to intramolecular interaction between the anthracene and amino chromophores. The study shows that linear alpha,omega-alkanediammonium ions, ((S)n)2+, form 1:1 and 1:2 inclusion complexes with the receptor and, at certain chain lengths (n = 6, 7), the complexed ions suppress the excimer signals.

A versatile synthetic strategy is described that is used for preparing doubly threaded, bistable [c2]daisy chain compounds. Kinetics measurements have shown that the acid/base-promoted extension/contraction movements of the polymeric [c2]daisy chain are faster than those of its monomeric counterpart.

A series of ferrioxamine B analogues that target the bacterium Yersinia enterocolitica were prepared. A case is presented in which biomimetic siderophore analogues deliberately designed for a particular bacterium could distinguish between related uptake systems of different microorganisms.

The oxidation chemistry of Fe(III)microperoxidase-8(MP-8) and Mn(III)MP-8 in water at ambient temperature with particular attention to the role played by protons in the formation of iron hydroperoxo and high-valent iron-oxo intermediates is studied. The results show that Compound zero is formed prior to what is analyzed as high-valent metal-oxo peptide radical intermediate.

Examines the performance of kinetics with microperoxidases. Implication of proteolytic breakdown product to cytochrome c containing octapeptide link to iron protoporphyrin IX; Use of rapid-scan stopped-flow spectroscopy in the specimen; Effects of proton in the oxidation of microperoxidases.

A versatile synthetic strategy, which was conceived and employed to prepare doubly threaded, bistable [c2]daisy chain compounds, is described. Propargyl and 1-pentenyl groups have been grafted onto the stoppers of [c2]daisy chain molecules obtained using a template-directed synthetic protocol. Such [c2]daisy chain molecules undergo reversible extension and contraction upon treatment with acid and base, respectively. The dialkyne-functionalized [c2]daisy chain (AA) was subjected to an [AA+BB] type polymerization with an appropriate diazide (BB) to afford a linear, mechanically interlocked, main-chain polymer. The macromolecular properties of this polymer were characterized by chronocoulometry, size exclusion chromatography, and static light-scattering analysis. The acid-base switching properties of both the monomers and the polymer have been studied in solution, using (1)H NMR spectroscopy, UV/vis absorption spectroscopy, and cyclic voltammetry. The experimental results demonstrate that the functionalized [c2]daisy chains, along with their polymeric derivatives, undergo quantitative, efficient, and fully reversible switching processes in solution. Kinetics measurements demonstrate that the acid/base-promoted extension/contraction movements of the polymeric [c2]daisy chain are actually faster than those of its monomeric counterpart. These observations open the door to correlated molecular motions and to changes in material properties.