Hydrogen bonding capability

The extraordinanly high polaiity of the fluonnated alcohols reflects their strong hydrogen-bonding capability [54] The P values of 10 2 for CF3CH2OH and 11 08 for (CF3)2CHOH compare with 10 6 and 12 1 for 50% formic acid and water, respectively [39]... 

The log octanol-water partition coefficient (log Pq/w) probably is the most frequently used physicochemical parameter in medicinal chemistry [101 104]. Octanol, with a polar head and a flexible, nonpolar tail, has hydrogen-bonding capabilities and amphilicity similar to... 

Interestingly, the UV maxima of the above dialkyl triafulvenes are only slightly influenced by the polarity and hydrogen-bonding capability of the solvent. In the cyclic triafulvene 195, countercurrent solvent shifts for the two main absorptions are observed. 

It is the sequence and types of amino acids and the way that they are folded that provides protein molecules with specific structure, activity, and function. Ionic charge, hydrogen bonding capability, and hydrophobicity are the major determinants for the resultant three-dimensional structure of protein molecules. The a-chain is twisted, folded, and formed into globular structures, a-helicies, and P-sheets based upon the side-chain amino acid sequence and weak intramolecular interactions such as hydrogen bonding between different parts of the peptide... 

Dehydrogenation activities, compared for tetralin and decalin [5,12] under the same superheated liquid-film conditions over the same Pt/C catalyst, exhibited around 3.9-63 times preference of tetralin (Table 13.3), which can certainly be ascribed to advantageous adsorption due to the a-bonding capability of its aromatic part [17-19]. It was, thus, confirmed experimentally that tetralin is superior to decalin as the organic hydrogen carrier for stationary applications in terms of rapid hydrogen supply or power density, provided that the density of fuel storage is unimportant. 

Association and mobilities are related in a complex way to the bulk properties of the solvent and solute. These properties include the charge density and distribution on the ions and the Lewis base properties, the strength and nature of the solvent molecule dipole, the hydrogen-bonding capability, and the intermolecular structure of the solvent. Some correlations can be made on the basis of mobility and association trends in series such as the halides and alkali metals within a single solvent others can be drawn between solvents for a given ion. It appears that conductance measurements provide a clear measure of the sum of ion-solvent interactions, but that other techniques must be used in conjunction with conductance if assessments of individual contributions from specific factors are to be made. 

Hydrogen bonding capability Berthelot, M. Bbsseau, F. Laurence, C. Ear. J. Org. Chem. 1998, 925 and relevant references therein. 

Platts et al. [39] reported linear free energy relation (LEER) models of the equilibrium distribution of molecules between blood and brain, relating log BB values to fundamental molecular properties, such as hydrogen-bonding capability, polarity/polarizability, and size. They used the following modified form of Abraham s general Eq. 46 ... 

Polarity term, mainly related to hydrogen bonding capability of a solute Logarithm of the partition coefficient (P) of neutral species Logarithm of the distribution coefficient (D) at a selected pH, usually assumed to be measured in octanol/water... 

Hydrogen bonding is now seen as an important property related to membrane permeation. Various scales have been developed [23]. Some of these scales describe total hydrogen bonding capability of a compound, while others discriminate between donors and acceptors [24]. It has been demonstrated that most of these scales show considerable intercorrelation [25]. 

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