1. Department of Chemistry
2. School of Science & Instrumental Analysis and Research Center
3. Shanghai University
4. Shanghai 200444, China
5. State Key Laboratory of Bioorganic & Natural Products Chemistry
6. Shanghai Institute of Organic Chemistry
7. Chinese Academy of Sciences
8. Shanghai 200032, China
9. State Key Laboratory of Natural Medicines
10. Center of Drug Discovery
11. China Pharmaceutical University
12. Nanjing 210009, China