474550-69-1

Atopaxar (E5555) hydrobromide is a potent, orally active, selective and reversible thrombin receptor protease-activated receptor-1 (PAR-1) antagonist. Atopaxar hydrobromide, an antiplatelet agent, interferes with platelet signaling. Atopaxar hydrobromide can be used for the research of atherothrombotic disease[1][2].

PAR1: 5.1 nM (IC₅₀)

[1] Chris Dockendorff, et al. Discovery of 1,3-Diaminobenzenes as Selective Inhibitors of Platelet Activation at the PAR1 Receptor. ACS Med Chem Lett. 2012 Mar 8; 3(3): 232–237. DOI:10.1021/ml2002696
[2] Motoji Kogushi, et al. The novel and orally active thrombin receptor antagonist E5555 (Atopaxar) inhibits arterial thrombosis without affecting bleeding time in guinea pigs. Eur J Pharmacol. 2011 Apr 25;657(1-3):131-7. DOI:10.1016/j.ejphar.2011.01.058
[3] Sun J, et al., Discovery and evaluation of Atopaxar hydrobromide, a novel JAK1 and JAK2 inhibitor, selectively induces apoptosis of cancer cells with constitutively activated STAT3. Invest New Drugs. 2020 Aug;38(4):1003-1011. DOI:10.1007/s10637-019-00853-w