In order to search for anti-arteriostenotic agents, a series of 2 (1H)-quinolinone derivatives was synthesized and evaluated for anti-thrombotic activity and for anti-hyperplastic activity. From this series,(−)-6-[3-[3-cyclopropyl-3-[(1R, 2R)-2-hydroxycyclohexyl] ureido] propoxy]-2 (1H)-quinolinone (1p, OPC-33509) was selected as the best candidate by balancing the efficacy on anti-thrombosis and anti-hyperplasia.