Molecular recognition thermodynamics

To understand fully processes such as molecular recognition, reactivity and bioactivity, it is therefore imperative to obtain a detailed insight into the thermodynamic and kinetic properties of the metal-based anticancer agent at hand. 

The selective binding of molecules to form productive complexes is of central importance to pharmacology and medicinal chemistry. Although kinetic factors can influence the yields of different molecular complexes in cellular and other non-equilibrium environments,1 the primary factors that one must consider in the analysis of molecular recognition are thermodynamic. In particular, the equilibrium constant for the binding of molecules A and B to form the complex AB depends exponentially on the standard free energy change associated with complexation. 

Chemical templates are being increasingly employed for the development of dynamic combinatorial libraries (DCL) [94-98]. These (virtual) libraries of compounds are produced from all the possible combinations of a set of basic components that can reversibly react with each other with the consequent potential to generate a large pool of compounds. Because of the dynamic equilibria established in a DCL, the stabilization of any given compound by molecular recognition will amplify its formation. Hence the addition of a template to the library usually leads to the isolation of the compound that forms the thermodynamically more stable host-guest complex (see Scheme 37). 

A Thermodynamic View for Global Understanding of Molecular Recognition. 67... 

A THERMODYNAMIC VIEW FOR GLOBAL UNDERSTANDING OF MOLECULAR RECOGNITION " ... 

Since the present theory has been shown to be useful in analyzing molecular recognition of relatively simple guests with most synthetic hosts, we now proceed to the supramolecular interactions in more sophisticated biological systems where relatively abundant thermodynamic data are available in the literature. 

So far, the studies of cucurbituril described have been thermodynamic investigations, in which factors contributing to the overall stability of molecular complexes have been explored. While bounteous, these only partly address the question of receptor specificity. For example, in biological systems the kinetics of noncovalent interactions, such as between enzymes and substrates, may be of greater consequence. Clearly, the dynamics of molecular recognition deserve additional attention. Cucurbituril provides diverse opportunities in this area [11]. 

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