Department of Chemistry;
College of Chemistry and Environmental Science;
Hebei University;
Baoding 071002;
China;
Department of Chemical Biology;
Peking University School of PharmaceuticalSciences;
Beijing100083;
China;
Department ofOral Pathology;
Stomatological Hospital;
Peking University;
Beijing100081;
China;
School of Pharmaceutical Sciences;
Capital University of Medical Sciences;
Beijing100054;
China;
Department ofBiology and Chemistry;
City University ofHong Kong;
Hong Kong;