Comparative study of hydrophobicity parameters of novel 5′-carbamates of zidovudine

Abstract

The lipophilic character of a series of 5′-carbamates of zidovudina has been studied. The lipophilicity was measured by means of reversed-phase thin layer chromatography (RP-TLC) and reversed-phase high performance liquid chromatography (RP-HPLC) techniques giving the corresponding RMw and log k′w parameters, respectively. These values were compared with those obtained by the classical shake flask methodology. RP-TLC assays were performed on the basis of thermodynamically true RM values, and buffer pH's 7.4 and 12.03 were chosen to determine the influence of the pH on the lipophilicity of the studied compounds. In addition, the influence of the organic modifier was studied in RP-TLC, showing the superiority of methanol as compared with acetone as the organic modifier, and physicochemical reasons have been discussed. Based on RP-TLC results, RP-HPLC studies were carried out using methanol and buffer pH 7.4 as mobile phase. Chromatographic data (RMW and log k′w) proved to be reliable parameters for describing the lipophilic properties of the test compounds.