To evaluate the neurotoxicity of selected derivates 5i, 5m, THA, and 7-PhO-THA in vitro, we tested the cytotoxic effects of the compounds in SH-SY5Y cells. The SH-SY5Y cell line was used because it is frequently associated with neurotoxicity evaluation . We tested the biological effects of 5i, 5m, THA, and 7-PhO-THA (0-100 µM) at three different time points: 6, 24 and 48 h (Table ). To evaluate the effects of a compound in cells, we measured intracellular dehydrogenase activity as a marker of cellular viability, glutathione (GSH) levels to estimate oxidative stress, and ATP level as a marker of the energy state of cells.