Pyr-​Pro-​Arg-​pNA  (Synonyms: S-2366)

Pyr-​Pro-​Arg-​pNA (S-2366) is a chromogenic peptidyl substrate, and a noncompetitive inhibitor that occupies the active sites of FXIa and FXIa-LC to block factor IX activation. Pyr-​Pro-​Arg-​pNA functions as a hydrolyzable substrate for FXIa’s catalytic domain, human APC, murine APC, and purified plasma kallikrein^[1][2][3][4].

Pyr-​Pro-​Arg-​pNA (0-1.5 mM) is hydrolyzed by purified human FXIa and FXIa-LC with K_m values of 225 μM and 357 μM^[1].
Pyr-​Pro-​Arg-​pNA noncompetitively inhibits human FXIa-mediated FIX activation with a K_i of 425 μM and human FXIa-LC-mediated FIX activation with a K_i of 420 μM, without altering the K_m values for FIX binding to either enzyme^[1].
Pyr-Pro-Arg-pNA can be hydrolyzed by purified recombinant murine activated protein C with essentially identical kinetic activity to purified human activated protein C^[3].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

502.52

C₂₂H₃₀N₈O₆

72194-57-1

O=C([C@@H]1CCC(N1)=O)N2[C@@H](CCC2)C(N[C@@H](CCCNC(N)=N)C(NC3=CC=C(C=C3)[N+]([O-])=O)=O)=O

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Sinha D, et al. Macromolecular substrate-binding exosites on both the heavy and light chains of factor XIa mediate the formation of the Michaelis complex required for factor IX-activation. Biochemistry. 2007;46(34):9830-9839.  [Content Brief]

  [2]. Miller T N. The molecular interactions of the catalytic domain of factor XIa (FXIa): Catalysis of substrates IX and S-2366, inhibition by the Kunitz protease inhibitory domain (KPI) of Protease Nexin 2 (PN2), and binding to the surface of activated platelets[M]. Temple University, 2007.

  [3]. Fernández JA, et al. Recombinant murine-activated protein C is neuroprotective in a murine ischemic stroke model. Blood Cells Mol Dis. 2003 May-Jun;30(3):271-6.

  [4]. Briseid K, et al. Part of purified human plasma kallikrein removed together with a remaining IgG fraction--immunoblot experiments and functional tests. Scand J Clin Lab Invest. 2002;62(1):21-24.