| Popis: |
The logarithms of the capacity factors, log k′, for several heteroaromatic systems (furan, pyrrole, benzofuran, indole, benzene and their alkyl, ester and amide derivatives) were determined on a Capcell Pak C18 column using methanol—buffer (pH 7.4) mobile phases of different compositions. These results and the log kw values, derived by a linear extrapolation of the plot of log k′ against the volume fraction of methanol to 0% methanol, were correlated with experimental log P values by taking into account the hydrogen-acceptor and hydrogen-donor effects. Whereas the hydrogen-donor effect was found to be minimized by using the log kw parameter, the hydrogen-acceptor effect was found to become insignificant in an eluent containing 50% methanol. Isocratic data determined at this eluent composition gave the simplest and best correlation. |
