Zhang, Zhen-Xing; Wu, Baolin; Wang, Bin; Li, Tie-Hai; Zhang, Peng-Fei; Guo, Li-Na; Wang, Wen-Jun; Zhao, Wei; Wang, Peng George Tetrahedron Letters, 2011, vol. 52, # 29 p. 3802 - 3804 doi: 10.1016/j.tetlet.2011.05.063