New peptide derivatives

摘要

Tripeptide derivatives, characterized by the general formula: R1-X-D-Arg-A-Arg-NH-R2 wherein R1 is hydrogen, alpha - or beta -naphtyl residue, lower alkyl residue which may be substituted with a carboxyl group, unsubstituted or substituted phenyl- or phenylalkyl residue. or a single bond with the proviso that when R1 is hydrogen then and only then X is a single bond A=Gly or Sar R2=an aromatic or heterocyclic residue which gives a compound R2-NH2 by enzymatic hydrolysis, which can be determined quantitatively or disalts and trisalts of inorganic or organic acids thereof, process for their preparation and method for determination of serine proteases, especially Factor Xa, or components which can interact with serine proteases or zymogen forms thereof.