1. School of Pharmaceutical Sciences, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, 920-1192, Japan
2. Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, 192-0392, Japan
3. National Institutes of Health (NIH), Wayne, Pennsylvania 19087, United States
4. Natural Products Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute (NCI), Frederick, Maryland 21702-1201, United States
5. Molecular Targets Program, Center for Cancer Research, National Cancer Institute, NCI at Frederick, Frederick, Maryland 21702-1201, United States
6. Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7568, United States
7. Chinese Medicine Research and Development Center, China Medical University and Hospital, 2 Yuh-Der Road, Taichung, 40447, Taiwan