1. School of Pharmaceutical Sciences, South-Central University for Nationalities, Wuhan 430074, China
2. State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Kunming 650201, China
3. University of Chinese Academy of Sciences, Beijing 100049, China
4. State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China