The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (Merck) reduction assay was used for measurement of compounds cytotoxicity. Cell viability was detected after 24 h incubation with the tested substances. For the assay, HepG2 cells were seeded into 96-well plates in 100 µL volume and density of 15 × 10 3 cells per well. Cells were allowed to attach overnight before the treatment. The stock solutions of tested compounds were prepared in DMSO (Merck), which were further serially diluted in the appropriate culture medium and added to the cells in a 96-well culture plate. The final concentration of DMSO did not exceed 1% (v/v).