Hydrophobicity parameters determined by reversed-phase liquid chromatography. I. Relationship between capacity factors and octanol-water partition coefficients for monosubstituted pyrazines and the related pyridines was written by Yamagami, Chisako;Ogura, Tamaki;Takao, Narao. And the article was included in Journal of Chromatography in 1990.Application of 6924-68-1 This article mentions the following:
The capacity factors (k‘) of monosubstituted pyrazines and 2-substituted pyridines were measured on a Capcellpack C18 column using methanol-buffer (pH 9.2) mobile phases of different compositions, and the relationship between log P (n-octanol-water partition coefficient) and log k‘ was analyzed. In all instances the amphiprotic substituents were eluted faster than expected on the assumption of log P-log k‘ linearity, reflecting that these groups act as hydrogen donors. For other substituents, a good linear relationship between log P and log k‘ was obtained with eluents containing 50-70% (volume/volume) of methanol. However, as the methanol content decreased, linearity no longer held and correction terms for the electronic effects and specific effects attributed to ester and amide groups were required. The relationship between log k‘ (pyrazine) and log k‘ (pyridine) was studied by applying a modified bidirectional Hammett-type correction for the component in π-value attributable to electronic effects of substituents and aza functions on the hydrogen-bonding solvation effect. The retention behavior changes systematically with changes in mobile phase composition In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Application of 6924-68-1).
Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.Application of 6924-68-1