Design, Synthesis, and Biological Activity of Novel Factor Xa Inhibitors: 4-Aryloxy Substituents of 2,6-Diphenoxypyridines

• Published in: Bioorganic & medicinal chemistry 2002-03, Vol.10 (3), p.657-666
• Main Authors: Ng, Howard P., Buckman, Brad O., Eagen, Keith A., Guilford, William J., Kochanny, Monica J., Mohan, Raju, Shaw, Kenneth J., Wu, Shung C., Lentz, Dao, Liang, Amy, Trinh, Lan, Ho, Elena, Smith, David, Subramanyam, Babu, Vergona, Ron, Walters, Janette, White, Kathy A., Sullivan, Mark E., Morrissey, Michael M., Phillips, Gary B.
• Format: Article
• Language: English
• Subjects: Administration, Oral; Animals; Biological and medical sciences; Biological Availability; Blood. Blood coagulation. Reticuloendothelial system; Cattle; Dogs; Drug Design; Factor Xa Inhibitors; Fibrinolytic Agents - chemical synthesis; Heterocyclic Compounds, 4 or More Rings - chemical synthesis; Heterocyclic Compounds, 4 or More Rings - pharmacokinetics; Heterocyclic Compounds, 4 or More Rings - pharmacology; Medical sciences; Pharmacology. Drug treatments; Pyridines - chemical synthesis; Pyridines - pharmacokinetics; Pyridines - pharmacology; Rats; Serine Proteinase Inhibitors - chemical synthesis; Serine Proteinase Inhibitors - pharmacokinetics; Serine Proteinase Inhibitors - pharmacology; Structure-Activity Relationship
• ISSN: 0968-0896; 1464-3391
• DOI: 10.1016/S0968-0896(01)00338-8

A novel series of triaryloxypyridines have been designed to inhibit factor Xa, a serine protease strategically located in the coagulation cascade. Inhibitor 5e has a K I against factor Xa of 0.12 nM and is greater than 8000- and 2000-fold selective over two related serine proteases, thrombin and trypsin, respectively. The 4-position of the central pyridine has been identified as a site that tolerates various substitutions without deleterious effects on potency and selectivity. This suggests that the 4-position of the pyridine ring is an ideal site for chemical modifications to identify inhibitors with improved pharmacokinetic characteristics. This investigation has resulted in inhibitor 5d, which has an oral availability of 6% in dogs. The synthesis, in vitro activity, and in vivo profile of this class of inhibitors is outlined. The synthesis, in vitro activity, and in vivo profile of a novel series of pyridine-based fXa inhibitors that show nanomolar potency is described. The 4-position of the central pyridine has been identified as a site that tolerates various substitutions without deleterious effects on potency and selectivity.