Low molecular weight bicyclic thrombin inhibitors

This invention relates to the discovery of heterocyclic competitive inhibitors of the enzyme thrombin having formula (I), their preparation, and pharmaceutical compositions thereof. As well, this invention relates to the use of such compounds and compositions in vitro as anticoagulants and in vivo as agents for the treatment and prophylaxis of thrombotic disorders such as venous thrombosis, pulmonary embolism and arterial thrombosis resulting in acute ischemic events such as myocardial infarction or cerebral infarction. Moreover, these compounds and compositions have therapeutic utility for the prevention and treatment of coagulopathies associated with coronary bypass operations as well as restenotic events following transluminal angioplasty.