Structure−Activity Relationship Study and Drug Profile of<i>N</i>-(4-Fluorophenylsulfonyl)-<scp>l</scp>-valyl-<scp>l</scp>-leucinal (SJA6017) as a Potent Calpain Inhibitor

Abstract

Novel N-arylsulfonyldipeptidyl aldehyde derivatives were prepared by DMSO oxidation from the corresponding dipeptide alcohol, and their potencies as calpain inhibitors were evaluated in vitro. Among them, N-(4-fluorophenylsulfonyl)-l-valyl-l-leucinal (8, SJA6017) potently inhibited calpains. 8 also inhibited cathepsin B and L but did not inhibit other cysteine proteases (interleukin 1beta-converting enzyme), serine proteases (trypsin, chymotrypsin, thrombin, factor VIIa, factor Xa), or proteasome. Preliminary cytotoxicity studies of 8 exhibited a relatively safe profile.