Solution-phase and solid-phase synthesis of novel transition state inhibitors of coagulation enzymes incorporating a piperidinyl moiety

2-Amino-3-piperidin-4-yl-propionic acid containing peptidomimetics are potent protease inhibitors when combined with an appropriate keto-thiazole or keto-carboxylic acid moiety. A novel P1 residue in factor Xa and thrombin inhibitors has been found resulting in IC50 values as low as 0.048 μM, a factor of ten more potent than Argatroban. Starting with non-chiral synthetic routes, a new stereospecific route was developed as well as a new solid-phase method.