[1] Tianjin Univ Tradit Chinese Med, Sch Chinese Mat Med, Tianjin 301617, Peoples R China
[2] Natl Univ Singapore, Dept Chem, Singapore 117543, Singapore
[3] Tianjin Univ Tradit Chinese Med, Tianjin Key Lab Therapeut Subst Tradit Chinese Med, Tianjin 301617, Peoples R China
[4] Natl Univ Singapore Suzhou, Res Inst, Suzhou 215123, Peoples R China