1. Department of Medicinal Chemistry, Shantou University Medical College, Shantou, Guangdong, 515041, P. R. China
2. Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, HKSAR, P. R. China
3. Clinical Research Centre, The First Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, 515041, P. R. China