Virtual screening, de novo derivative generation, and molecular dynamics (MD) simulation were performed using Discovery Studio Client v2.5.0.9164 (DS2.5; Accelrys Inc., San Diego, CA). The two-dimensional and three-dimensional structures of TCM compounds were generated using ChemBioOffice 2008 (Perki-nElmer Inc., Cambridge, MA). Comparative molecular field analysis (CoMFA) and comparative molecular similarities indices analysis (CoMSIA) models were constructed using SYBYLß 8.3 package (Tripos Inc., St. Louis, MO).