[Os(IV)Cl(5)(Hazole)](-) complexes: synthesis, structure, spectroscopic properties, and antiproliferative activity.
By exploring the Anderson type rearrangement reactions, osmium(IV) complexes of the general formula [cation](+)[Os(IV)Cl(5)(Hazole)](-), where [cation](+) = n-Bu(4)N(+), Hazole = 1H-pyrazole (Hpz) (1), 1H-indazole (Hind) (2), 1H-imidazole (Him) (3), 1H-benzimidazole (Hbzim) (4), 1H,2,4-triazole (Htrz) (5), have been synthesized. To improve water solubility of tetrabutylammonium compounds, complexes with [cation](+) = Na(+) [Hazole = Hpz 6), Hind (7), Htrz (8)] or H(2)azole(+) [Hazole = Hpz (9), Hind (10), Htrz (11)] have been also prepared with the aim of testing them for cytotoxicity in cancer cells. In addition, the preparation of the complex {(n-Bu(4)N)(2)[Os(IV)Cl(6)]}(2)[Os(IV)Cl(4)(Him)(2)] (12) is also reported. The compounds have been comprehensively characterized by elemental analysis, electrospray ionization (ESI) mass spectrometry, spectroscopy (IR, UV-vis, 1D and 2D NMR), cyclic voltammetry, X-ray crystallography (1-6 and 12) and magnetic susceptibility (5). Complexes 6, 7, 9 are kinetically inert in aqueous solution and resistant to hydrolysis. Compounds 6-11 were found to possess modest antiproliferative acitivity in vitro against CH1 (ovarian carcinoma), A549 (non-small cell lung carcinoma), and SW480 (colon adenocarcinoma) cells with IC(50) values in the 10(-4) M concentration range. Replacement of azolium cations by sodium had significant effects; cytotoxicity increased in the case of the pyrazole system from 3 (A549) to the 5.5-fold (CH1).
Büchel
Gabriel E
GE
University of Vienna, Institute of Inorganic Chemistry, Austria.
Stepanenko
Iryna N
IN
Hejl
Michaela
M
Jakupec
Michael A
MA
Arion
Vladimir B
VB
Keppler
Bernhard K
BK
D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D006801:Humans; D006868:Hydrolysis; D007191:Indazoles / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008280:Magnetics; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D009992:Osmium / Q000737:chemistry*; D011720:Pyrazoles / Q000737:chemistry*; D012995:Solubility; D014867:Water / Q000737:chemistry
D007191:Indazoles; D009942:Organometallic Compounds; D011720:Pyrazoles; D014867:Water; D009992:Osmium; C031280:pyrazole