Properties of η5-pentamethylcyclopentadienyl rhodium(III) and iridium(III) complexes with quinolin-8-ol and their cytostatic activity

Reaction of dimers [M(η5-C5Me5)Cl2]2 (M-Rh, Ir) with quinolin-8-ol in molar ratio 1:2 leads to formation of monomer complexes [Rh(η5-C5Me5)Cl(qol)] (1) and [Ir(η5-C5Me5)Cl(qol)] (2) (qol = quinolin-8-olate). Compounds 1 and 2 have been characterized with elemental analysis and spectroscopic methods. 1H NMR spectra revealed that quinolin-8-olate is coordinated via oxygen and nitrogen atoms. The 1H NMR and 13C NMR spectra showed that carbon and hydrogen atoms of pentamethylcyclopentadienyl ligand are equivalent. The structure of rhodium complex has been calculated using DFT B3LYP method. The calculated geometry of complex 1 agrees very well with data found for rhodium complexes containing Cl, C5Me5 and qol ligands. Both complexes are active antitumor and antibacterial agents.

Graphical abstractComplexes [Rh(η5-C5Me5)Cl(qol)] (1) and [Ir(η5-C5Me5)Cl(qol)] (2) (qol = quinolin-8-olate) have been characterized with elemental analysis and spectroscopic methods. Quinolin-8-olate ligand is coordinated via oxygen and nitrogen atoms and carbon and hydrogen atoms of pentamethylcyclopentadienyl group are equivalent. The structure of rhodium calculated using DFT B3LYP method agrees very well with data found for rhodium complexes containing Cl, C5Me5 and qol ligands. Both complexes are very active cytostatic agents against tumor cells. They reveal also high activity against Gram-positive bacteria.Figure optionsDownload full-size imageDownload as PowerPoint slide