MODIFIED CHEMOTACTIC PEPTIDES - SYNTHESIS AND BIOLOGICAL-ACTIVITY OF HCO-MET-DELTA(Z)LEU-DELTA(Z)PHE-OME

For-Met-Delta(2)Leu-Delta(2)Phe-OMe (3) has been synthesized as a new analogue of the prototypical chemotactic agent For-Met-Leu-Phe-OMe (fM LP-OMe). Compound 3 is characterized by the presence of two consecutiv e alpha,beta-didehydro amino acid residues [Delta(2)Leu = (Z)-alpha,be ta-didehydroleucine; Delta(2)Phe = (Z)-alpha,beta-didehydrophenylalani ne] located at the central and C-terminal position, respectively. When tested on human neutrophils the N-formyltripeptide 3, although less a ctive than the parent, is able to induce chemotaxis, superoxide anion production and lysozyme release. The activity of 3 has been compared t o that of related fMLP-OMe analogues containing a single Delta(2)Phe r esidue located at the C-terminal position.