1. Drug Discovery and Design Centre, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Graduate School of the Chinese Academy of Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, China, and School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China hliu@mail.shcnc.ac.cn