122223422222651313The invention provides methods of making and using compounds of the formula (I) or a pharmaceutically acceptable salt thereof wherein n is an integer between 1 and 2 inclusively m is an integer between 0 and 2 inclusively X is selected from the group consisting of CH or N R is selected from the group consisting of CHNH and (Formula (II)) R is selected from the group consisting of H OH NH and acetyl R is selected from the group consisting of H benzyloxycarbonyl and benzyisulfonyland R is selected from the group consisting of OH (Formulae (III) (IV) (V) (VI)) wherein p is an integer between 0 and 2 inclusively Y is selected from the group consisting of 0 S S(=0) S0 methylene CH(OH) CH(NH) CH(CH OH) CH(CH NH) or N(R) R is selected from the group consisting of H or a simple (C1 C3) alkyl and R6 is selected from the group consisting of H a simple (C C) alkyl or a simple (C C) acyl. These compounds are useful as anticoagulant agents as a result of their selective dual inhibition of thrombin and prothrombinase.