Prediction of log kw using MCIs and LSER methods for heterocyclic nitrogen compounds

The HPLC capacity factors(k') measured on a C-18 column, using methanol-water mobile phase of different compositions, were determined for 15 heterocyclic nitrogen compounds. The linear relationship between the log k' values and the percentage of the methanol in the eluent was studied for each compound. The log k(w)' values of these compounds were obtained by extrapolating the retention data in binary solvent system to pure water eluent. Various MCI's (molecular connectivity indices) were calculated and LSER(linear solvation energy relationship) parameters were observed for these compounds. Good correlations were established between MCI's and log k(w)', and between LSER parameters and log k(w)'. The present correlation can be used to predict log k(w)' values for other derivatives.