Desolvation energies

Trifluoroacetic acid has been examined as a solvent and chlorination of benzene in this is first-order in aromatic and chlorine, but for benzene a higher activation energy (11.4, determined from data at 25.0 and 45.4 °C) was obtained than for chlorination in carbon tetrachloride this unexpected result was attributed to an increase in desolvation energy of the reactants273. 

Harinipriya S, Sangaranarayanan MV. 2002. Hydrogen evolution reaction on electrodes Influence of work function, dipolar adsorption, and desolvation energies. J Phys Chem B 106 8681-8688. 

In series with a desolvation energy barrier required to disrupt aqueous solute hydrogen bonds [14], the lipid bilayer offers a practically impermeable barrier to hydrophilic solutes. It follows that significant transepithelial transport of water-soluble molecules must be conducted paracellularly or mediated by solute translocation via specific integral membrane proteins (Fig. 6). Transcellular permeability of lipophilic solutes depends on their solubility in GI membrane lipids relative to their aqueous solubility. This lumped parameter, membrane permeability,... 

MS Karls, RD Rush, KF Wilkinson, TJ Vidmar, PS Burton, MJ Ruwart. Desolvation energy A major determinant of absorption, but not clearance, of peptides in rats. Pharm Res 8 1477-1481, 1991. 

In this model, one can argue that a peptide must have both an affinity for the interface (favorable n-octanol partition coefficient) and small desolvation energy (favorable A log PC) in order to efficiently cross a cell membrane. On the other hand, this model also predicts that a peptide with a large n-octanol/water partition coefficient and large desolvation energy, due to a significant number of polar groups, should adsorb and remain at the membrane interface. Both of these predicted events have been observed in the laboratory. 

Not all structure-based design experiments are successful. Attempts to displace the arginine residue that caps the SI pocket of HFC by forming a salt link with carboxylate or hydroxyl moiety were unsuccessful [42]. However, these failed attempts offer some redeeming features in the refinement of parameters that can be used to evaluate the energetic potentials for displacing buried water molecules as well as the inherent desolvation energies for polar compounds. 

Benson and Haugen s approach is sufficiently successful so that it could perhaps be adapted to solution reactions. Problems with DE and desolvation energies may not be overcome, but even rough estimates of the electrical factors affecting SS would be useful. 

Determination of Atomic Desolvation Energies from the Structures of Crystallized Proteins. 

In these centres, the negative charge is concentrated on the heteroatom. The centre-counter-ion interaction is much stronger than with carbanion centres. This is manifested by a tendency to aggregate and solvate formation. The reactivity of this kind of ion pair may exceed the reactivity of free ions, due to the unequal contribution of the desolvating energies of ion pairs and free ions [103],... 

Potential energy descriptors proposed as an indicator of hydrophobicity [Oprea and Waller, 1997]. Originally, they were calculated using the finite difference approximation method the linearized Poisson-Boltzmann equation was solved numerically to compute the electrostatic contribution to solvation at each grid point. Desolvation energy field values were calculated as the difference between solvated (grid dielectric = 80) and in vacuo (grid dielectric = 1). 

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