1. State Key Laboratory of Natural and Biomimetic Drugs, Peking University, 100083, Beijing, People's Republic of China, and Traditional Chinese Medicine College, Shenyang Pharmaceutical University, 110016, Shenyang, People's Republic of China, and Chemical Test Center, Beijing Normal University, 100073, Beijing, People's Republic of China, and Institute of Pharmaceutical Biology, Heinrich Heine University Duesseldorf, D-40225 Duesseldorf, Germany