1. Key Laboratory of Preclinical Study for New Drugs of Gansu Province, State Key Laboratory of Applied Organic Chemistry and Institute of Biochemistry and Molecular Biology, Lanzhou University, Lanzhou, 730000 (P.R. China), Fax: (+86) 931‐891‐2567
2. State Key Laboratory of Chiroscience and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon (Hong Kong)