This paper deals with the design, syntheses, and inhibition tests of new low molecular weight thrombin inhibitors utilizing cyanopeptides, the secondary metabolites of cyanobacteria with interesting biological activities, as new lead structures. Starting with aeruginosin 98-B (1) as a lead structure, we have developed and synthesised new, selective acting inhibitors of serine proteases (RA-1005 and RA-1009, which are suitable targets for further structure-activity studies.

New Cyanopeptide-Derived Low Molecular Weight Inhibitors of Trypsin-Like Serine Proteases. -Design, syntheses and inhibition tests of new low molecular weight thrombin inhibitors (VII) and (X) utilizing the cyanopeptide aeruginosin 98 B as a lead structure are described. Derivatives (VI) and (Xa) act as selective inhibitors of serine proteases. -(RADAU*, G.; SCHERMULY, S.; FRITSCHE, A.; Arch.