1. Department of Medicinal Natural Product Chemistry, School of Pharmaceutical Sciences, Hebei Medical University, Shijiazhuang Hebei Province, China;
2. Hebei Province Key Laboratory of Research and Development for Chinese Medicine, Institute of Chinese Materia Medica, Chengde Medical College, Chengde, Hebei Province China;
3. Basic Medical Institute, Chengde Medical College, Chengde, Hebei Province, China