1. College of Pharmacy, Yeungnam University, 214-1 Dae-Dong, Gyongsan 712-749, South Korea, Hanmi Research Centre, Hanmi Pharm Co. Ltd., Dongtam-myeon, 377-1 Hwaseong-si, Gyeonggi-do, 445-913, South Korea, and College of Pharmacy, Hanyang University, 1271, Sa-3-Dong, Ansan 426-791, South Korea