1. Hunan Provincial Key Laboratory of Cytochemistry, School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha 410114
2. Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1
3. Laboratory of Chemical Biology and Traditional Chinese Medicine Research, Ministry of Education, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081