1.College of Traditional Chinese Pharmacy, Beijing University of Traditional Chinese Medicine, Beijing 100102, China; 2.College of Chemistry, Jilin University, Changchun 130012, China; 3.Pharmaceutical College, Jilin University, Changchun 130012, China; 4.Center of Basic Chemical Experiment, Jilin University, Changchun 130012, China; 5.Department of Pharmaceutical Sciences, College of Pharmacy, North Dakota State University, Fargo, ND, USA 58105