Synthesis of an elastase inhibitor by monosubstitution of arginine-5 with valine at the reactive site in a trypsin inhibitor from squash seeds (CMTI III)

Using the solid-phase procedure an analog of trypsin inhibitor CMTI III containing Val5 instead of Arg5 in position P1, was synthesized. The substitution in only this one position P1 increased the affinity of synthetic inhibitor to porcine pancreatic elastase and human leukocyte elastase by the factor of 10(3) and 10(7), respectively.