Cytotoxicity, anti-HSV activity, and therapeutic index of Hsp90 inhibitors.

Note: The values are the mean ± SD of three independent experiments.aThe cytotoxic effect was determined by the MTT assay. CC50 was defined as the concentration reducing cell viability by 50%.bThe antiviral activity was determined by the plaque reduction assay. IC50 was the concentration that inhibited 50% of HSV replication.cThe therapeutic index (TI) was defined as the ratio of CC50 to IC50.