Molecular recognition process

The weak intemiolecular forces that are principally involved in stabilizing receptor-substrate interactions and involved in molecular recognition processes (16) are summarized in Table 2. Examples are shown in Figure 1. 

In biological systems one of the primary modes of molecular recognition processes occurs via H-bond formation. Research concerning design and synthesis of molecular components that can self-assemble via H-bonding interactions has been reported [90,155]. 

Carbohydrate conformation plays a key role for molecular recognition processes, and their determination contributes to the understanding of many biological processes. The latest NMR methodological developments for conformation determination are discussed here, and representative examples are given. 

Carbohydrates not only act as ligands, but they can also provide scaffolds for molecular recognition processes. It is well known that cyclodextrins (CDs) are able to form an inclusion complex with specific guest molecules. In the last years, NMR experiments combined with other techniques have been used to highlight different recognition events. 

The interactions between solutes and solvents are noncovalent in nature (barring the occurrence of chemical reactions), and therefore fall into the same category as those that govern molecular recognition processes, the formation and properties of liquids and solids, physical adsorption, etc. Hydrogen bonding, in its many manifestations, is a particularly prominent and important example. 

Ideally the electrochemical molecular recognition process should result in a large shift of the redox potential of the host species. The minimum magnitude of a potential shift is gauged by experimental error. For most voltammetric techniques, this error is about 5 mV. According to (6), the potential shift is determined by the ratio KoxIKied. This ratio reflects the influence of the redox reaction upon complexation, in other words, the RCE. So far, the coupling has... 

Lobmaier, Ch., Hawa, G., Gotzinger, M., Wirth, M., Pittner F., Gabor, F., Direct monitoring of molecular recognition processes using fluorescence enhancement at colloid coated microplates. J Mol Recognit 14, 1-8 (2001). 

There are several types of natural and synthetic molecular hosts, such as cyclodextrin and cyclophane, that are shaped to accommodate neutral and charged organic molecules in the three-dimensional cavity. The inclusion complexation by molecular hosts is driven by various weak forces like van der Waals, hydrophobic, hydrogen bonding, ion-dipole, and dipole-dipole interactions, and therefore the molecular recognition process seems much more complicated. In expanding the scope of the present theory, it is intriguing and inevitable to perform the extrather-... 

Replacement of carbon atoms in the cyclic aliphatic side chain of proline with nitrogen leads to the azaprolines where incorporation of an additional imino group may affect molecular recognition processes via electrostatic interactions. While the proline analogues imidazoli-dine-2-carboxylic acid (3-azaproline, 15) and pyrazolidine-3-carboxylic acid (5-azaproline, 16) allow for additional side-chain modifications in peptidomimetic structures, with pyr-azolidine-2-carboxylic acid (2-azaproline, 17) (Table 2), where the a-CH is replaced by nitrogen, the peptide backbone is modified with consequently strong conformational effects. 

Dynamic features of supermolecules correspond on the intermolecular level to the internal conformational motions present in molecules themselves and define molecular recognition processes by their dynamics in addition to their structural aspects. They add a further important facet to the behaviour of these species and may influence their functional features in reactions and transport processes as well as in polymolecular assemblies. 

Molecular recognition processes rest on selective intermolecular interactions between complementary components. They may affect the properties of the system at the molecular, the supramolecular and the material levels by respectively 1) perturbing the electronic and optical properties of the components 2) generating supramolecular species 3) inducing organization in condensed phase. All three effects are of importance with respect to the NLO properties of the material and its constituents. 

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