STABILITY STUDY OF 2'-DEOXYURIDINE BY LIQUID-CHROMATOGRAPHY

Previous stability studies on 2'-deoxyuridine (dUrd) made use of UV sp ectrophotometry. However, this technique does not allow dUrd to be det ermined separately from its anomer and pentopyranosyl isomers formed d uring acid degradation. The anomerization and isomerization have been monitored by TLC before, but the separation between dUrd and its alpha -anomer was not optimal. Therefore, the aim of this study was to deter mine the rate constants of the degradation of dUrd, using a recently d eveloped liquid chromatographic method. Rate constants of degradation of dUrd were determined at several pH values in the range 1-12. Studie s at different temperatures showed that the Arrhenius equation is appl icable at pH 1 and 7. To elucidate further the mechanism of hydrolysis in acidic media, some degradation tests were performed at pH 1 on the alpha-anomer and pentopyranosyl isomers of dUrd.