SYNTHESIS OF A TRIHEXACONTAPEPTIDE CORRESPONDING TO THE SEQUENCE 8-70 OF EGLIN-C AND STUDIES ON THE RELATIONSHIP BETWEEN THE STRUCTURE AND THE INHIBITORY ACTIVITY AGAINST HUMAN-LEUKOCYTE ELASTASE, CATHEPSIN-G AND ALPHA-CHYMOTRYPSIN

A trihexacontapeptide corresponding to the sequence 8-70 of eglin c and its related peptides were synthesized by the conventional solution method and their inhibitory activity against human leukocyte elastase, cathepsin G and α-chymotrypsin was examined. Although synthetic eglin c (41-49) inhibited cathepsin G and α-chymotrypsin (Ki = 4.0 × 10-5 M and 2.0 × 10-5 M, respectively) but not leukocyte elastase, the synthetic trihexaconta-peptide potently inhibited cathepsin G, α-chymotrypsin and leukocyte elastase (Ki = 1.8 × 10-9 M, 1.4 × 10-9 M and 2.2 × 10-9 M, respectively). The relationship between the stucture of eglin c and the inhibitory activity against the above enzymes is also described. © 1990.