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Robin D Rogers

Publications and source records attributed to Robin D Rogers.

40 records · Page 3Linked to original sources

QSPR correlation of the melting point for pyridinium bromides, potential ionic liquids.

In an attempt to develop predictive tools for the determination of new ionic liquid solvents, QSPR models for the melting points of 126 structurally diverse pyridinium bromides in the temperature range 30-200 degrees C were developed with the CODESSA program. Six- and two-descriptor equations with squared correlation coefficients (R(2)) of 0.788 and 0.713, respectively, are reported for the melting temperatures. The models illustrate the importance of information content indices, total entropy, and the average nucleophilic reactivity index for an N atom.

Journal Article↗

Comparison of an empirical and a theoretical linear solvation energy relationship applied to the characterization of solute distribution in a poly(ethylene) glycol-salt aqueous biphasic system.

A Linear Solvation Energy Relationship (LSER) developed by Abraham has been applied to the partition of organic solutes in an Aqueous Biphasic System (ABS) and to published values of their 1-octanol/water partition coefficients. The results are compared to the application of a conceptually similar Theoretical Linear Solvation Energy Relationship (TLSER) developed by Famini and co-workers. Differences and similarities in the molecular properties highlighted by each LSER are discussed. The theoretical relationship of Famini, although modeled on the approach of Abraham, seems not to encapsulate molecular properties in the same way as the Abraham's empirical relationship. However, this theoretical approach has the great merit of computational simplicity, and it is concluded that efforts directed toward its improvement could be rewarding.

Journal Article↗

Aqueous biphasic systems. Partitioning of organic molecules: a QSPR treatment.

The partitioning of 29 small organic probes in a PEG-2000/(NH4)2SO4 biphasic system was investigated using a quantitative structure-property relationship (QSPR) approach. A three-descriptor equation with the squared correlation coefficient (R2) of 0.97 for the partition coefficient (log D) was obtained. All descriptors were derived solely from the chemical structure of the compounds. Using the same descriptors, a three-parameter model was also obtained for log P (octanol/water, R2=0.89); predicted log P values were used as an external descriptor for modeling log D.

Journal Article↗

Theoretical scales of hydrogen bond acidity and basicity for application in QSAR/QSPR studies and drug design. Partitioning of aliphatic compounds.

Phenomenological analysis of existing hydrogen bond (HB) donor and acceptor scales and apparent physical considerations have enabled the establishment of new quantitative scales of hydrogen bond basicity and acidity. Chemical structures represented by molecular graphs and the orbital electronegativities of Hinze and Jaffe are utilized as an input data. The scales obtained correlate well with several experimental solvent polarity scales such as and, pK(HB), and E(T)(30). To demonstrate the applicability of the new quantities, we have applied them to seven equilibrium partitioning data sets: octanol-water, hexadecane-water, chloroform-water, gas-water, gas-octanol, gas-hexadecane, and gas-chloroform partition coefficients. The hydrogen bond descriptors when supplemented by a cavity-forming term and a dipolarity term show high performance in correlations of the partition coefficients of aliphatic compounds. These new HB descriptors can be used in studying hydrogen bonding and fluid phase equilibria as well as scoring functions in ligand docking and descriptors in ADME evaluations.

Drug Design↗