Protein-kinase inhibiting peptide derivatives

Peptide derivatives of general formula I: Z-Z'-Z"-R-K-G-A-L-R-Z'"-Z-Z-J-X I where Z is an (L)arginine or (L)lysine residue or is absent, Z' is (L)phenylalanine or (L)tyrosine or is absent, Z" is an (L)alanine residue or is absent, -R-K-G- A-L-R- represents the sequence -(L)Arg-(L)Lys-(L)Gly- (L)Ala-(L)Leu-(L)Arg-, Z'" is a glutamine, phenylalanine, leucine or valine residue, Z is a lysine or arginine residue and Z is a residue of a natural amino acid or is absent, or again is one of the following amino acid derivative residues: where n is a whole number from 0 to 4, J is -NH- or -O-, or, when Z is residue (ii). is absent, and X is a straight or branched (C3-19) alkyl group or the residue of a bile acid, and their pharmaceutically acceptable salts, are active as protein-kinase inhibitors.