Twenty amines and oximes from deoxybenzoins were prepared and evaluated for their inhibitory activity against Helicobacter pylori urease. Among these compounds, high inhibitory activities were observed in amines and oximes, especially amines 1b (IC(50)=0.011 mM) and 6b (IC(50)=0.047 mM) exhibited good in vitro activities, and were comparable to acetohydroxamic acid (AHA). The hydroxyl groups on deoxybenzoin skeleton may be responsible for the inhibitory activity and coordinate with the nickel (active site) on enzyme. A direct interaction may exist between the OH group of hydroxylamines or NH group of amines and His alpha323 of H. pylori urease, which is on the flap of the enzyme active site.