N-ALKYL-TRIPEPTIDE-ALDEHYDES AND USE AS ANTICOAGULANTS

The invention relates to new peptide-aldehydes and a process for the preparation thereof, furthermore to pharmaceutical compositions containing the same. According to a feature of the present invention there are provided new peptide-aldehyde derivatives corresponding to the general formula (I) (I) wherein R1 represents hydrogen or C1-6 alkyl group, R2 stands for C1-6 alkyl group, furthermore R1 and R2 are linked to the amino group of the Xxx alpha-amino acid, Xxx represents a D-phenylalanine residue or a D-alpha-amino acid group having in the side chain a C1-4 alkyl group, Pro stands for L-proline residue, Yyy stands for L-, D- or DL-arginine residue and A represents an acid residue. The new peptide-aldehyde derivatives of the invention possess valuable anticoagulant activity.