RELATIONSHIP BETWEEN STRUCTURE AND REVERSED-PHASE THIN-LAYER CHROMATOGRAPHIC LIPOPHILICITY PARAMETERS IN A GROUP OF PIPERAZINE DERIVATIVES

The R-M values of substituted piperazine derivatives, I, have been det ermined on silanized silica gel plates with buffered aqueous acetone w ith or without n-octylamine as the mobile phase. Chromatographically d etermined lipophilicity of substances containing aromatic nuclei that are separated by a sufficiently flexible chain, presented a decrease i n comparison with the lipophilicity calculated on the basis of tabulat ed fragmental constants. The intramolecular hydrophobic interaction of aromatic nuclei resulting from their stacking conformation could be a probable explanation for this phenomenon.