Water Soluble Copper(II) and Zinc(II) Complexes of Mangiferin: Synthesis, Antitumour Activity and DNA Binding Studies

The reactions of mangiferin (H-MF) with Cu(II) and Zn(II) yielded [Cu(MF)(OH)(H2O)]x5H2O and [Zn(MF)(OH)(H2O)]x4H2O. The MTT assay against four tumour cell lines revealed that the Cu complex generally showed higher in vitro cytotoxicity vs. free H-MF than the Zn complex, which may be due to the different bioactivities of Cu(II) and Zn(II). DNA binding studies of both complexes vs. H-MF indicated that they tended to bind intercalatively with DNA. Both complexes also exhibited topoisomerase I inhibition at 100 μM, which could be due to their DNA binding affinities.