1. State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 China
2. Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
3. Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China
4. Asymchem Life Science Co., Ltd. TEDA Tianjin 300457 China