Send to

Choose Destination
Bioorg Med Chem. 2011 Dec 15;19(24):7425-34. doi: 10.1016/j.bmc.2011.10.045. Epub 2011 Oct 20.

Conformationally restricted analogs of the direct thrombin inhibitor FM 19.

Author information

Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 428 Church Street, Ann Arbor, MI 48109-1065, USA.


The serine protease thrombin plays several key roles in the clotting cascade within the hemostatic system, such as in fibrin formation and platelet activation. Thus, development of an inhibitor that binds to the enzyme's active site (a direct thrombin inhibitor) offers an approach for the treatment of thrombus-associated diseases. Previous structure-activity relationship studies originally based on the bradykinin breakdown product Arg-Pro-Pro-Gly-Phe (RPPGF) led to the development of lead compound FM 19 (d-Arg-Oic-Pro-d-Ala-Phe(p-Me)-NH(2)). The recently determined X-ray structure of FM 19 in the active site of thrombin has revealed sites of modification to potentially improve inhibition. In this study, we report the synthesis and biological characterization of nine peptides that replace only the d-Arg residue of the FM 19 sequence, investigating ways to add conformational restriction, modification of the basic moiety at the end of the side chain, and removal of the charge from the N-terminus. Two of these peptides, 6 and 7 (IC(50) values of 0.51 and 0.45 μM, respectively), show similar potency to the best compounds in the FM 19 series reported thus far.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center