Fondaparinux Free Base is a synthetic pentasaccharide that mediates the interaction of HEPARIN with ANTITHROMBINS and inhibits FACTOR Xa; it is used for prevention of VENOUS THROMBOEMBOLISM after surgery. Fondaparinux is a clinically approved anticoagulant pentasaccharide for the treatment of thrombotic diseases, displays better efficacy and biosafety than other heparin-based anticoagulant drugs.