Antitumor activity of new hydridotris(pyrazolyl)borate ruthenium(ii) complexes containing the phosphanes PTA and 1-CH3–PTA

Abstract

The synthesis and full characterization of new half-sandwich ruthenium(II) complexes containing κ³(N,N,N)-hydridotris(pyrazolyl)borate (κ³(N,N,N)-Tp) and the water-soluble phosphanes 1,3,5-triaza-7-phosphatricyclo[3.3.1.1^3,7]decane (PTA) and 1-methyl-3,5-diaza-1-azonia-7-phosphatricyclo[3.3.1.1^3,7]decane (1-CH₃-PTA) has been explored. Single crystal X-ray diffraction analysis for complex [RuCl{κ³(N,N,N)-Tp}(PMe₂Ph)(1-CH₃-PTA)][CF₃SO₃]·2NCMe is also reported. DNA binding properties of the ruthenium complexes have been evaluated by mobility shift assay and MALDI-TOF mass spectrometry. The in vitro antitumor activity of these compounds was assessed by examining their ability to inhibit cell proliferation in a number of human cancer cell lines (NCI-H460, SF-268, MCF-7) and non-tumor human umbilical vein endothelial cells (HUVEC). Some of these new compounds show promising cytotoxic activity with IC₅₀ values in the low micromolar range, and display differential effects on cancer and normal cell growth.