203521-17-9

In our investigation of factor Xa inhibitors, a series of 1-(6-chloronaphthalen-2-yl)sulfonyl-4-(4,5,6,7-tetrahydrothiazolo[5,4-c] pyridine-2-carbonyl)piperazines 3a-i were synthesized. In vitro inhibitory activities of the compounds against factor Xa and coagulation are summarized. Among the compounds, 3c and 3d, possessing a carbamoyl or N-methylcarbamoyl moiety, showed potent inhibitory activities when administered orally to rats.

This application relates to a compound of formula (I) (or a pharmaceutically acceptable salt thereof) as defined herein, pharmaceutical compositions thereof, and its use as an inhibitor of factor Xa, as well as a process for its preparation and intermedia

The present invention provides compounds which specifically inhibit FXa, which are effective when orally administered and which are useful as a safe medicine for the prevention or treatment of diseases caused by thrombus or infarction. Compounds of this invention are piperazinones of the formula: wherein R1is an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group; the ring A is an optionally substituted divalent nitrogen-containing heterocyclic group, in addition to being substituted by the group of the formula: and the group of the formula: Y is an optionally substituted divalent hydrocarbon group or an optionally substituted divalent heterocyclic group; X is a direct bond or an optionally substituted alkylene chain; Z is (1) an amino group substituted with an optionally substituted hydrocarbon group, (2) an optionally substituted imino group or (3) an optionally substituted nitrogen-containing heterocyclic group; provided that when X is a direct bond and Z is an optionally substituted 6-membered nitrogen-containing aromatic heterocyclic group, Y is an optionally substituted divalent hydrocarbon group or an optionally substituted divalent unsaturated heterocyclic group; or a salt thereof.