Whole-Molecule Calculation of Log P Based on Molar Volume, Hydrogen Bonds, and Simulated 13C NMR Spectra was written by Schnackenberg, Laura K.;Beger, Richard D.. And the article was included in Journal of Chemical Information and Modeling in 2005.Product Details of 6924-68-1 This article mentions the following:
The prediction of Log P is usually accomplished using either substructure or whole-mol. approaches. However, these methods are complicated, and previous whole-mol. approaches have not been successful for the prediction of Log P in very complex mols. The observed chem. shifts in NMR spectroscopy are related to the electrostatics at the nucleus, which are influenced by solute-solvent interactions. The different solvation effects on a mol. by either water or methanol have a strong effect on the NMR chem. shift value. Therefore, the chem. shift values observed in an aqueous and organic solvent should correlate to Log P. This paper develops a rapid, objective model of Log P based on molar volume, hydrogen bonds, and differences in calculated 13C NMR chem. shifts for a diverse set of compounds A partial least squares (PLS) model of Log P built on the sum of carbon chem. shift differences in water and methanol, molar volume, number of hydrogen bond donors and acceptors in 162 diverse compounds gave an r2 value of 0.88. The average r2 for 10 training models of Log P made from 90% of the data was 0.87±0.01. The average q2 for 10 leave-10%-out cross-validation test sets was 0.87±0.05. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Product Details of 6924-68-1).
Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazine has the elements of symmetry for the point group D2h. It has three mutually perpendicular two-fold axes. It also has three mutually perpendicular planes of symmetry. As a result, pyrazine also has a centre of symmetry. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.Product Details of 6924-68-1