A single enantiomer of a potent and selective inactivator of KIAA1363, a MAGE hydrolase an enzyme that is upregulated in aggressive cancers from various tissues (IC50 = 150 nM when tested as a racemic mixture in SK0V-3 cells); activity of the individual enantiomers of AS 115, i.e,. (+)-AS 115 and (−)-AS 115, has not been determined.