Investigation of the kinetics of degradation of hexopyranosylated cytosinenucleosides using liquid chromatography

Liquid chromatography was used to follow the degradation of hexopyranosylat ed cytosine nucleosides in buffers of acid, neutral and alkaline pH and of constant ionic strength. The compounds were found to degrade by hydrolysis to cytosine and/or by deamination to the corresponding uracil nucleosides. Degradation in acid is influenced by the number of sugar hydroxyl groups, p resence of sugar double bonds and the type of anomer. Stability of some of the compounds was compared with that of related thymine nucleosides. Temper ature studies support a unimolecular mechanism of hydrolysis at pH 1.22.