1. Department of Natural Medicinal Chemistry; China Pharmaceutical University; Nanjing 210009 P. R. China
2. Tasly R&D Institute; Tasly Pharmaceutical Co., Ltd.; Tianjin 300410 P. R. China
3. Natural Products Research Laboratories; UNC Eshelman School of Pharmacy; University of North Carolina; Chapel Hill NC 27599 USA
4. Department of Pharmacology; Nanjing Medical University; Nanjing 210029 P. R. China
5. Chinese Medicinal Research and Development Center; China Medical University and Hospital; Taiwan 40402 Taiwan