1. School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, and Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, P.R. China
2. Chemical and Pharmaceutical Development, Research and Development, Bayer AG, 42096 Elberfeld, Germany
3. Chemical and Pharmaceutical Development, Research and Development, Bayer AG, 13342 Berlin, Germany
4. Chemical and Pharmaceutical Development, Research and Development, Bayer AG, Beijing 100020, China