1. College of Pharmacy, Ewha Womans University, 11-1 Daehyun-dong, Seodaemun-gu, Seoul 120-750, Korea, In2Gen Co., Ltd., 608 Daerung Posttower II Building, 182-13 Guro-dong, Guro-gu, Seoul 152-050, Korea, and College of Pharmacy, Sungkyunkwan University, Suwon 440-746, Korea