Synthesis of peptide inhibitors of human spleen fibrinolytic proteinase (SFP) and human leukocyte elastase-like proteinase (ELP)

Stereoisomers of specific substrates for SFP and ELP, Suc-L-Tyr-L-Leu-L-Val-pNA and Suc-L-Ala-L-Tyr-L-Leu-L-Val-pNA, were synthesized by the conventional solution method. Suc-L-Tyr-D-Leu-D-Val-pNA was found to be an effective and specific inhibitor of SFP and ELP. Suc-L-Tyr-L-Leu-L-Val-Pipe and Suc-L-Tyr-D-Leu-D-Val-Pipe inhibited only SFP very slightly and showed no inhibitory effect on ELP. Both Dan-L-Tyr-L-Leu-L-Val-pNA and Dan-L-Tyr-D-Leu-D-Val-pNA exhibited an inhibitory effect on both SFP and ELP.