Functional group contributions

GM Zentner, JR Cardinal, J Feijen, S-Z Song. Progestin permeation through polymer membranes. IV. Mechanism of steroid permeation and functional group contributions to diffusion through hydrogel films. J Pharm Sci 68 970-975, 1979. 

Xiang, T. X. and Anderson, B. D. (2002). A computer simulation of functional group contributions to free energy in water and a DPPC lipid bilayer, Biophys. J., 82, 2052-2066. 

Rogers, J. A. and Davis, S. S. (1980). Functional group contributions to the partitioning of phenols between liposomes and water, Biochim. Biophys. Acta-Biomem., 598, 392—404. 

Andrews, P.R., Craik, D.J., Martin, J.L. Functional group contributions to drug-receptor interactions./. Med. Chem. 1984, 27, 1648-1657. 

The left-hand term in eq. 9.3.6 corresponds to the n-alkyl contribution and the right-hand term to the functional group contribution. Nc is the number of carbon atoms in the molecule and rc is a constant. The contribution parameters a and be refer to the alkyl group and the parameters bf and bfc to the functional group. For compounds with homogeneous multifunctional groups (e.g., alkanediols or polychlorinated alkanes), the model takes the following form ... 

The homomorph of a polar molecule is deLned as a nonpolar molecule having very nearly the same molecular size and shape. Alternatively, the dispersion contributions can be estimated using functional group contribution, and the formula ... 

The other components can also be estimated using additive functional group contributions, and tables of group contributions for polarand hydrogen-bonding contributions are available (Hansen and Beerbower, 1971 Van Krevelen and Hoftyzer, 1976 Barton, 1983). If we label the polar functional group contributiorFp, the polar contributions are summed in this fashion ... 

The acid-base properties of DOM are of intrinsic interest because acidic functional groups contribute to the acid-base balance of natural waters, affect complexation and transport of dissolved metals, and interact with mineral surfaces. The concentrations of carboxyl and phenolic functional groups are among the most widely measured and reported properties of DOM. Methodologically, there are two basic approaches for measuring acidic group content—indirect titrations and direct titrations (Perdue et al., 1980 Perdue, 1985 Ritchie and Perdue, 2003). 

From the results it can be concluded that the following types of functional groups contribute more or less strongly to the early release of chlorine ... 

IV. THE STRENGTHS OF FUNCTIONAL GROUP CONTRIBUTIONS TO DRUG-RECEPTOR INTERACTIONS... 

IV. The Strengths of Functional Group Contributions to Drug-Receptor Interactions... 

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