Specific inhibitor of puromycin-sensitive aminopeptidase with a homophthalimide skeleton: identification of the target molecule and a structure–activity relationship study
,3-dione (2: PIQ-22) was found to be a potent and specific inhibitor of puromycin-sensitive aminopeptidase (PSA). Lineweaver-Burk plot analysis showed that PSA is inhibited by PIQ-22 in a non-competitive manner. Structure -activity relationship studies indicated that tautomerism of the imidobenzoylketone group in the cyclicimide moiety of the PIQ-22 skeleton is important for the inhibitory activity