Abstract:From the aerial parts of Ruta chalepensis L., grown in Jordan, two furanocoumarins (bergapten and chalepensin), one fl avonoid glycoside (rutin) as well as several minor compounds have been isolated. The structural elucidation of these compounds was established based on spectral data (UV, IR, MS, 1 H-NMR and 13 C-NMR). In Jordan, R. chalepensis is recommended for the treatment of rheumatism, mental disorders and menstrual problems. Fresh and dried leaves are used as fl avoring agent in food and beverages. Antiplatelet activities of the crude methanolic and ethylacetate extracts in addition to the three isolated major compounds were measured by the aggrometric method according to Beretz and Casenave. Optical aggregometer connected to dual channel recorder was used for measuring aggregation. Both, ethylacetate and methanol extracts inhibited ADP-induced platelet aggregation (ADP-IA) of human blood. However, only ethylacetate extract was able to induce 50% inhibition of collagen-induced platelet aggregation (Co-IA) platelet rich plasma. Bergapten was more active against ADP-IA compared to chalepensin while the latter was more active against Co-IA compared to bergapten.