1. Kobe Pharmaceutical University, Higashinada-ku, Kobe 658-8558, Japan, Gifu Pharmaceutical University, Mitahora-higashi, Gifu 502-8585, Japan, Faculty of Pharmaceutical Sciences, Kinki University, Kowakae, Higashiosaka 577-8502, Japan, and Yunnan Pharmaceutical Group Corporation, 547 Beijing Road, Kunming, Yunnan, People's Republic of China