Hydroxypyridinone Derivatives: Synthesis And Cytotoxic Evaluation

A series of 3-hydroxypyridin-4-one derivatives (HPOs) as bidentate iron (III) chelating agents were synthesized from 3-hydroxypyran-4-ones (maltol and ethyl maltol) in three steps through protection of hydroxyl group. The protected compounds were then reacted with suitable primary amines to give benzylated pyridinones. Finally, the benzyl group was removed by catalytic hydrogenation to produce the desired products. The partition coefficient of the free ligands and their iron (III) complexes were determined in an aqueous/octanol system using shake-flask method. The cytotoxic effects of these iron chelators against MCF-7 and MDA-MB-231 cancer cells were also evaluated using MTT assay. The results revealed that cytotoxicity of synthesized compounds were closely related to the lipophilycity of them so that the most lipophilic compound (4f) showed the highest activity; whereas compound 4a as a more hydrophilic agent showed the lowest cytotoxic effect; Although these compounds were cytotoxic at high concentration (? 0.1 mM).