The ratio of prodrug IC50 to parent compound IC50 was calculated, revealing a 4-to 78-fold improvement in reducing cellular cytotoxicity when using the prodrug approach instead of the parent HDAC inhibitors. Compounds 4 and 10 were found to be the least toxic prodrugs against J774A.1 cells. It was not possible to calculate accurate IC50 values for both compounds as they demonstrated minimal or no cellular toxicity even at tested concentrations up to 100 µM. At the same time, compound 5 and 6 show moderate toxicity in J77A.1 cells, pointing towards potential off-target effects in this cell line.