A study of master thesis( in the department of pharmaceutical chemistry at the College of Pharmacy at the University of Basrah) discussed coumarin derivatives activities in a study of a title preparation and evaluation of the pharmacokinetic efficacy of the new coumarin derivatives) by the M.Sc student Scenaria Muhammad Al-Awad. The thesis dealt with preparing new compounds for the coumarin-oxadiazole derivatives as a hybrid system because of its effective role and wide applications in recent years, and this has been proven through melting points, infrared spectroscopy, proton magnetic resonance spectroscopy and mass spectroscopy. Pharmacology also studied the prepared compounds as antioxidant compounds compared with vitamin C, and anti-blood clotting compared with heparin in addition to anti-breast cancer MCF-7. The study included preparing the derivatives first through chemical chain reactions and diagnosing them with proof, and included compounds [S4H, S4F, S4Cl, S4CO], and tests were conducted to estimate the lethal dose of these compounds. S4F has demonstrated significant anticoagulant activity Similar to heparin at concentration (50, 100, 200 mg / m), while the compound S4CO gave an important anti-cancer activity against MCF-7 cancer cells, while the compound S4H showed the most active compounds as an antioxidant.