1. a School of Chinese Medicine, The Chinese University of Hong Kong , Hong Kong
2. b National Institutes for Food and Drug Control , Beijing, 100050, China
3. c Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing, 100050, China
4. d Department of Medicinal Chemistry and Pharmacognosy , College of Pharmacy, The University of Illinois at Chicago , Chicago, IL, 60612, USA