Ligand, ligands dynamic

Gray, H. B., and Langford, C. H. (1968). Chem. Eng. News, April 1, 68. A excellent survey article, "Ligand Substitution Dynamics," that presents elementary concepts clearly. 

The underlying physical principles of NMR have been established and are well understood.8 Applications of both solid- and solution-state NMR spectroscopy can be found in many different disciplines. It is routinely used in structural elucidation of organic and inorganic compounds, polymers, and biomolecules (e.g., proteins, nucleic acids, and carbohydrates). Additionally, NMR can be used to study molecular interactions (e.g., protein-protein and protein-ligand), molecular dynamics, and chemical reactions. It has also been used extensively in medical research and imaging (magnetic resonance imaging). 

Macchioni and coivorkers [147] have investigated the effect of the counterion on CO/Styrene copolymerization catalyzed by [Pd(ti -Ti -C8Hi20Me)bipy]X, (92, Figure 1.21) where X is the counterion. The bipyridine ligand shows dynamic behavior and a series of NMR spectra recorded between 204 and 302 K (Figure 1.21) pro-... 

SCHEME 1. The dynamic behavior of organozinc compounds involves C—Zn exchange and C—Zn bond inversion as main processes. Aggregation and ligand exchange dynamics complete the overall picmre describing the dynamics of these compounds... 

Considerable attention has been paid to the dynamic behaviour of Mo2+ complexes in solution and lH NMR spectroscopy has been an essential probe. These properties have been reviewed710 and emphasis given to the point that the barrier to rotation about the triple bond is determined only by steric factors associated with ligand-ligand interactions.205 95MoNMR... 

Dimeric and cluster compounds containing isocyanide ligands exhibit dynamic behavior in solution. The dimer Cp2Mo2(CO)5CNMe exists as a mixture of nonbridged isomers and permutamers which are rapidly inter-converted by unimolecular processes at RT. The isocyanide passes rapidly from one metal atom to the other via carbonyl or carbonyl-isocyanide doubly bridged species (205). 

Buranda, T., Jones, G., Nolan, J., Keij, J., Lopez, G. P., and Sklar, L. A. (1999). Ligand receptor dynamics at streptavidin coated particle surfaces A flow cytometric and spectrofluorimetric study. / Phys. Chem. B. 103, 3399-3410. 

Another example of the application of lineshape analysis to ligand dynamics is described in Section 4.3 for the drug trimetrexate, which binds to dihydrofolate reductase (DHFR). From that example it is clear that the techniques described above can equally be applied to ligands when bound to their receptors. In some cases significant but highly specific mobility appears to be present at the bound site. 

Similarly, the techniques already described for determining the dynamics of ligands or macromolecules are also directly applicable to complexes. Again, specific examples are given in Section 4, including the use of relaxation data to study dynamics in HIV protease/inhibitor complexes and the use of dynamic lineshape studies for studying correlated ligand-protein dynamics in DHFR complexes. 

Verkhivker GM (2004) Computational analysis of ligand binding dynamics at the intermolecular hot spots with the aid of simulated tempering and binding free energy calculations, Mol J Graph Model, 22(5) 335-348... 

Time-Resolved Infrared Studies of Ligand Dynamics in Heme Proteins... 

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