Substituted aniline was diazotized and subsequently reduced to give phenylhydrazine hydrochloride, which reacted with potassium thiocyanate to produce aryl-substituted thiosemicarbazide, followed by reaction with isopentyl nitrite and hydrochloric acid and neutralization with alkali to afford 3-aryl-1,2,3,4- oxatriazole-5-imine. The imine obtained finally was coupled with aspirin to give target compounds 6a～6l_. The structures of all compounds were identified by MS, IR, ¹H NMR spectra and elemental analysis. The in vitro inhibitory activities against plate-let aggregation in rats and in vivo inhibitory effect on pulmonary thrombus formation in mice were investigated. The preliminary results showed that some tested compounds exhibited potential antithrombotic activity and deserve further study.

Key words: aspirin, NO donor, antithrombotic activity, 3-aryl-1,2,3,4-oxatriazole-5-imine