1. a School of Pharmaceutical Sciences, Hebei Medicinal University, Department of Natural Product Chemistry , 336 Zhongshan East Road, 050017, Shijiazhuang, China
2. b Mount Marty College, Department of Chemistry , 1105W, 8th Street, Yankton, SD, SD 57078, USA
3. c Graduate School of Agricultural Sciences, Tohoku University, Laboratory of Applied Bioorganic Chemistry, Division of Life Science , 1-1 Tsutsumidori-Amamiya, Aoba-ku, Sendai, 981-8555, Japan