High-performance liquid chromatographic study of some biologically active analogues of arabinosylcytosine

Abstract

The effects of methanol concentration, pH and flow-rate of the mobile phase and column temperature on the retention of two cytidine deaminase-resistant analogues (cyclocytidine hydrochloride and 5′-chloro-5′-deoxyarabinosylcytosine) of the antineoplastic agent arabinosylcytosine (araC) and their metabolites in a reversed-phase system were examined. Cyclocytidine hydrochloride (p K a 6.60) changed its retention significantly in the pH range 6–7 and when the methanol concentration increased from 3 to 5% comparing to other compounds. The greatest changes in the capacity factors were observed for 5′-chloro-araC (p K a = 3.84) in mobile phases with low methanol concentrations (up to 5%, v/v). The effect of temperature was most significant in the case of 5′-chloro-araC. Its retention decreased the most when the temperature was changed from ambient to 30°C. The relationship between capacity factors and hydrophobicity (logarithm of partition coefficients) of the studied compounds was also studied.