The trypsin-like serine protease plasmin is a target for the development of antifibrinolytic drugs for use in cardiac surgery with cardiopulmonary bypass or organ transplantations to reduce excessive blood loss. The optimization of our recently described substrate-analogue plasmin inhibitors, which were cyclized between their P3 and P2 side chains, provided a new series with improved efficacy and excellent selectivity. The most potent inhibitor 8 ...
