Hydrophobicity parameters determined by reversed-phase liquid chromatography. XII. Comparison of capacity factors and octane/methanol-water partition coefficients for monosubstituted pyrazines, and effect of octanol added to both partitioning systems was written by Yamagami, Chisako;Iwasaki, Kaname;Ishikawa, Ayako. And the article was included in Chemical & Pharmaceutical Bulletin in 1997.Application In Synthesis of Ethyl pyrazine-2-carboxylate This article mentions the following:
Partition coefficients (P) of pyrazine and its COOMe derivative (strong hydrogen bond acceptor), were measured for the octane/aqueous methanol partitioning system (PO/MW) at different methanol (MeOH) concentrations and the dependence of log PO/MW on the methanol concentration was compared to the corresponding change in log k’ (k’: capacity factor) obtained by reversed-phase liquid chromatog. with aqueous methanol. Next, in order to make the chromatog. system approx. more closely to the octanol/water partitioning system, a small quantity of octanol was added to the eluents and also to the octane/aqueous methanol partitioning system and further comparisons were made. It was found that the octanol effect was min. at 50% MeOH, suggesting that the chromatog. system with eluents containing about 50% MeOH has properties more similar to the octanol/water partitioning system than with eluents of other compositions This confirms our previous result that the log k’ parameter obtained at 50% MeOH yields a better correlation with log Poct (Poct: octanol/water partition coefficient) than those obtained at other mobile phase compositions in the range from 5 to 70% MeOH. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Application In Synthesis of Ethyl pyrazine-2-carboxylate).
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. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Application In Synthesis of Ethyl pyrazine-2-carboxylate