Fig 4. Toxicity of compounds for mammalian cells.

HeLa S3 cells were incubated in media containing either compounds or vehicle for 20 hr. Viability was measured by resazurin reduction and expressed as the percent fluorescence compared to untreated cells at (A and B) 13 μg/mL and (C and D) 107 μg/mL. Cells incubated with medium containing DMSO and 0.1% Triton X-100 were included as negative and positive controls, respectively. Untr: untreated. Dotted horizontal line indicates 100% viability.