[Synthesis of N-alpha-benzyloxycarbonyl-4-amidinophenylalanine amides as thrombin inhibitors].

Based on 4-cyanophenylalanine, the title compounds had been obtained by benzyloxycarbonylation of the amino group, subsequent formation of the activated ester by 4-nitrophenol, its aminolysis and at least change of the cyano function to the amidine function via thiocarbamides and thioimid acid esters. The inhibitor effect against thrombin of the pyrrolidid 16 is analogous to those of the adequate N alpha-tosyl compound.