1. College of Plant Science, Jilin University, Changchun 130062, P. R. China
2. College of Chemistry, Jilin University, Changchun 130012, P. R. China
3. Institute of Medicinal Plant Department, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, P. R. China
4. State Key Laboratory of Dao-di Herbs, China Academy of Chinese Medical Sciences, Beijing 100700, P. R. China
5. State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, Jilin University, Changchun 130012, P. R. China