Study supramolecular structure

Rowland, S.P. and Bertoniere, N.R., Chemical methods of studying supramolecular structure, in Cellulose Chemistry and Its Applications, Nevell, T.P. and Zeronian, S.H., Eds., Ellis Horwood Ltd., Chichester, England, 1985, chap. 4, p. 112. 

Johari. G.P. Dielectric Methods in Studying Supramolecular Structures. In Comprehensive Supramolecular Chemistry, Vol. 8, Physical Methods in Supramolecular Chemistry, Davies. J.E.D.. Ripmeester. J.A., Eds. Elsevier Oxford. 1996. Chap. 3. 

Overall, luminescent probes provide a powerful and versatile tool for studying supramolecular structures and their practical uses. Multiple intrinsic and extrinsic parameters of chemical and biological samples are measurable by their means. Accompanying multiple detection formats facilitate the collection of large amounts of information about supramolecular structures, their macro- and micro-... 

Rowland, S.P. and Bertoniere, N. R., Chemical methods of studying supramolecular structure, in... 

The formation of fibronectin fibrils, another relatively well-studied supramolecular structure of ECM polymers, was extensively studied in vitro as well. Many different cell types synthesize fibronectin and secrete it as a disulfide-bonded dimer composed of 230-270 kDa subunits. Each subunit contains three types of repeating modules, types I, II, and III. These modules comprise functional domains that mediate interactions with other ECM components, with cell surface receptors and with fibronectin itself. Fibronectin matrix assembly involves binding domains and repeating modules from all regions of fibronectin which participate in interactions with cell surface receptors and with other fibronectin molecules. Newly secreted fi-... 

Macrocyclic receptors made up of two, four or six zinc porphyrins covalently connected have been used as hosts for di- and tetrapyridyl porphyrins, and the association constants are in the range 105-106 M-1, reflecting the cooperative multipoint interactions (84-86). These host-guest complexes have well-defined structures, like Lindsey s wheel and spoke architecture (70, Fig. 27a), and have been used to study energy and electron transfer between the chromophores. A similar host-guest complex (71, Fig. 27b) was reported by Slone and Hupp (87), but in this case the host was itself a supramolecular structure. Four 5,15-dipyridyl zinc porphyrins coordinated to four rhenium complexes form the walls of a macrocyclic molecular square. This host binds meso-tetrapyridyl and 5,15-dipyridyl porphyrins with association constants of 4 x 107 M-1 and 3 x 106 M-1 respectively. 

Several ligands containing pyridine or related groups and sulfur atoms have been synthesized and the silver complexes studied the ligands used are shown in Figure 15. Many of the complexes have a supramolecular structure. 

In recent years, with increasing recognition of the roles played by specific noncovalent interactions in biological systems and chemical processes, the science of noncovalent assemblies- often called supramolecular science- has aroused considerable interest [76], The remaining part of this article reviews some important studies made on rotaxane and catenane, two classic types of supramolecular structure. 

We chose to show the application of techniques employed to study supramolecular dynamics to host systems that have defined binding sites and, therefore, form host-guest complexes with defined stoichiometries. CDs were chosen because they represent a host with only one binding site, and therefore can be viewed as a model system for hosts with the lowest degree of complexity. DNA was chosen because it provides multiple binding sites for small molecules, i.e. intercalative and groove binding, while the DNA is structurally fairly well defined. 

Supramolecular concepts involved in the size- and shape-selective aspects of the channels and cavities of zeolites are used to control the selectivity of reactions of species produced by photoexcitation of molecules encapsulated within zeolites. The photochemistry of ketones in zeolites has been extensively studied. Photoexcitation of ketones adsorbed on zeolites at room temperature produces radical species by the Norrish type 1 reaction. A geminate (born together) radical pair is initially produced by photolysis of the ketone, and the control of the reaction products of such radicals is determined by the initial supramolecular structure... 

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