The degradation of diamino analogues of 2′- or 3′-deoxyadenosine and of 9-(2-deoxy-β-D-threo−pentofuranosyl)adenine or 9-(3-deoxy-β-D-threo-pentofuranosyl)adenine in buffers of acid, neutral and alkaline pH and constant ionic strength was followed by liquid chromatography. The rate of hydrolysis at acid pH was found to be related to the position and configuration of the amino group on the sugar moiety. The compounds under study were found to be more stable than corresponding monoaminated nucleosides, which have been reported to be more stable than the hydroxyl nucleosides. Liquid chromatographic analyses indicate that acid hydrolysis involves cleavage of the N-glycosyl bond as the major degradative process, together with another minor process. pH-rate profiles, activation parameters and deuterium isotope solvent effects are discussed.