1. Department of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education), 15 Yucai Road, Guilin 541004, P. R. China
2. Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research,
School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China
3. Institut
de Chimie de Strasbourg, CNRS-UMR 7177, Université de Strasbourg, 4 Rue Blaise Pascal, 67008 Strasbourg Cedex, France