1. College of Chemistry, Nanchang University, Nanchang 330031, Jiangxi, P.R. China
2. National Research Center for Carbohydrate Synthesis, Jiangxi Normal University, Nanchang 330022, Jiangxi, P.R. China
3. College of Chemistry and Molecular Sciences, the Institute for Advanced Studies (IAS), Wuhan University, Wuhan 430072, Hubei, P.R. China