Inhibitor for restenosis after percutaneous coronary arterioplasty

Abstract From the Canadian patent

An inhibitor for restenosis after percutaneous coronary arterioplasty (PTCA) which comprises, as an active ingredient, a compound of the following formula (1) (1'), or a pharmaceutically acceptable salt thereof: (see formulas), wherein R1 and R2 are independently a hydrogen atom a, halogen atom, a trifluoromethyl group a nitro group, a C1-, C6 alkyl group or a C1-C6 alkoxyl group and R1 and R2 may, be linked to form a methylenedioxy group; R3 is an optionally substituted aryl group, an optionally substituted aromatic heterocyclic group, an optionally substituted 5 to 7-membered cycloalkyl or cycloalkenyl group; R4 is a hydrogen atom, a hydroxyl group, an -S-glutathione residue, an -S- a …