Cyclodextrins theoretical studies

To date, D coefficients of carbohydrates established with the PFGSE approactf - " have been undertaken to (1) validate the theoretical self-diffusion coefficients calculated from MD trajectories, (2) demonstrate the complexation of lanthanide cations by sugars,(3) probe the geometry of a molecular capsule formed by electrostatic interactions between oppositely charged P-cyclodextrins, (4) study the influence of concentration and temperature dependence on the hydrodynamic properties of disaccharides, and (5) discriminate between extended and folded conformations of nucleotide-sugars. ... 

Dodziuk, H (2002). Rigidity versns flexibility. A review of experimental and theoretical study pertaining to the cyclodextrin nonrigidity. Journal of Molecular Structure, 614, 33 5. 

Simply mixing solutions of the tetracationic diphosphine (175) with a tetraanionic calix[4]arene leads to the formation of supramolecular heterocapsules that can bind a transition metal ion within the cavity of the assembly, providing a new class of potential supramolecular catalysts. Sulfonated aryl-phosphines and -diphosphines form supramolecular adducts with cyclodextrins that are also of interest as new ligand systems,and the mechanism of such inclusion processes has attracted a theoretical study. ... 

Theoretical Studies of Cyclodextrins and Their Inclusion Complexes... 

THEORETICAL STUDIES OF CYCLODEXTRINS AND THEIR INCLUSION COMPLEXES 189... 

The work of Lipkowitz raises important caveats, applicable not only to theoretical studies of cyclodextrins, but to molecular modeling in general First, results often are dependent on the computational method used. Secondly, the conformation in hand may be one of many local energy minima, as opposed to the global energy... 

T. Furukl, F. Hosokawa, M. Sakurai, Y. Inoue and R. Chujo, Microscopic medium effects on a chemical reaction. A theoretical study of decarboxylation catalyzed by cyclodextrins as an enzyme model, J. Am. Chem. Soc., 115 (1993) 2903. 

Absorption and fluorescence spectra of 7-aminocoumarin derivatives have been recorded and the photophysics of coumarin inclusion complexes with 0- and y-cyclodextrins investigated. Solvent effects on the photophysical behaviour of pyrrolocoumarin derivatives are similar to those on the psorolens . Vibronic exciton bands and the absorption spectra of Eosin Y dimers have been analysed theoretically and compared with experimental data. Picosecond spectroscopic studies have been made on the ionic photodissociation dynamics of malachite green leucocyanide . The lowest state produces ions within 0.1 to 0.5 ns whilst for higher states 6-13 ps are sufficient for the development of charge separation. The photophysics of crystal violet in a series of n-... 

In keeping with the fundamental importance of this subject and the intense recent activity in this area, several excellent reviews have already summarized different aspects of photophysical processes in organized assemblies. The development in this area up to 1991 was summarized in the volume edited by Rama-murthy [2-4]. Subsequently, several authors discussed the effect of cyclodextrins on many photophysical processes [5]. The binding of organic probes with cyclodextrins and other hosts in aqueous medium arises as a result of the hydrophobic effect. The different aspects of hydrophobic binding have also been reviewed extensively [1]. Many organized assemblies involve an interface between two drastically different media. The properties of molecules at various interfaces have been recently studied using a munber of new experimental and theoretical techniques. This aspect is reviewed by Eisenthal [6a], Robinson et al. [6b], and others [6c-e]. 

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