The novel synthetic substance MR-387C [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl-L-valyl- L-prolyl-L-leucine] as an aminopeptidase M inhibitor

Abstract

In the course of screening for new aminopeptidase M inhibitors which were expected to be analgesic, immunopotentiating, or anti-metastatic agents, the novel synthetic substance MR-387C[(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl-L-valyl-L-prolyl-L-leucine] (M.W. 504 daltons) was obtained. It was competitive with the substrate and had an value of () and an inhibition constant () of . This novel MR-387C was compared with various known inhibitors of aminopeptidase M. It inhibited the enzyme more strongly than any other microorganism-originated inhibitor, except probestin.