1. Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of Pharmacy, Chengdu University, Chengdu 610106, P. R. China
2. Jinhua Branch, Sichuan Industrial Institute of Antibiotics, School of Pharmacy, Chengdu University, Jinhua 321007, P. R. China
3. Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, P. R. China
4. Zhongshan Institute for Drug Discovery, the Institutes of Drug Discovery and Development, Chinese Academy of Sciences, Zhongshan 528400, P. R. China