Liu, Huan; Li, Yi; Wang, Xiang-Ying; Wang, Bo; He, Hai-Yun; Liu, Ji-Yan; Xiang, Ming-Li; He, Jun; Wu, Xiao-Hua; Yang, Li Bioorganic and Medicinal Chemistry Letters, 2013 , vol. 23, # 8 p. 2349 - 2352