Synthesis, characterization and cytotoxic effect of vanadocene complexes bearing substituted 2,2 '-bipyridines and 4,5-diazafluoren-9-one
Abstract
This study describes the synthesis of vanadocene compounds [Cp'2V(L)][OTf]2, where Cp' is substituted cyclopentadienyl ring and L is N,N-chelating ligand. All prepared compounds were characterized by analytical and spectroscopic methods.
The structures of [(η5-C5H4Me)2V(bpy)][OTf]2, [(η5-C5H4iPr)2V(bpy)][OTf]2.CH2Cl2, [Cp2V(4,4'-Me2-bpy)][OTf]2, [Cp2V{4,4'-(MeO)2-bpy}][OTf]2.MeOH and [(η5-C5H4Me)2V(dafone)][OTf]2 were further confirmed by the X-ray diffraction analysis. The cytotoxicity study, performed on human leukemia cells MOLT-4 and HL-60, demonstrates that the activity of the vanadocene complexes strongly depends on the nature of the coordinated chelating ligand.
The high cytotoxicity was observed for the complex bearing 2,2'-bipyridine, [(η5-C5H4Me)2V(bpy)][OTf]2, that shows IC50 values close to the data observed for cisplatin.