Unsymmetric Mono- and Dinuclear Platinum(IV) Complexes Featuring an Ethylene Glycol Moiety: Synthesis, Characterization, and Biological Activity

Eight novel mononuclear and two dinuclear platinum(IV) complexes
were synthesized and characterized by elemental analysis, one- and
two-dimensional NMR spectroscopy, mass spectrometry, and reversed-phase
HPLC (log kw) and in one case by
X-ray diffraction. Cytotoxicity of the compounds was studied in three
human cancer cell lines (CH1, SW480, and A549) by means of the MTT
assay, featuring IC50 values to the low micromolar range.
Furthermore a selected set of compounds was investigated in additional
cancer cell lines (P31 and P31/cis, A2780 and A2780/cis, SW1573, 2R120,
and 2R160) with regard to their resistance patterns, offering a distinctly
different scheme compared to cisplatin. To gain further insights into
the mode of action, drug uptake, DNA synthesis inhibition, cell cycle
effects, and induction of apoptosis were determined for two characteristic
substances.