Fondaparinux Sodium (Org 31540)

Fondaparinux Sodium (Org 31540) (CAS No.: 114870-03-0) is a synthetic heparin derived pentasaccharide research reagent broadly categorized as an antithrombin dependent coagulation modulator and selective factor Xa pathway inhibitor for thrombosis biology and anticoagulation mechanism studies in biomedical research and drug discovery settings, with a mechanistic profile centered on high affinity interaction with antithrombin III that induces a conformational state favoring accelerated neutralization of activated factor Xa and consequent suppression of downstream thrombin generation within the coagulation cascade, while showing functional activity that is commonly described from nanomolar to low micromolar experimental ranges across biochemical and plasma based assay formats and with reported inhibitory potency situated in the micromolar domain for specific assay conditions; in research practice it is frequently used as a reference or comparator molecule for evaluating antithrombin axis pharmacology, factor Xa selective screening paradigms, coagulation biomarker modulation, and structure activity informed design of next generation anticoagulation focused tool compounds, and it is also incorporated into in vitro enzyme systems, ex vivo plasma coagulation platforms, and in vivo thrombosis related animal models to interrogate target engagement, pathway selectivity, exposure response relationships, and translational pharmacology endpoints, where the concentrations or doses used in experiments typically depend on specific experimental designs and research objectives.