Solution equilibrium studies of anticancer ruthenium(II)-η <sup>6</sup>- p-cymene complexes of pyridinecarboxylic acids
- Author(s)
- Eva Sija, Christian G. Hartinger, Bernhard K. Keppler, Tamas Kiss, Eva A. Enyedy
- Abstract
Stoichiometry and stability of antitumor ruthenium(II)-η
6-p- cymene complexes of picolinic acid and its 6-methyl and 6-carboxylic acid derivatives were determined by pH-potentiometry,
1H NMR spectroscopy and UV-Vis spectrophotometry in aqueous solution in the presence or absence of coordinating chloride ions. The picolinates form exclusively mono-ligand complexes in which they can coordinate via the bidentate (O,N) mode and a chloride or a water molecule is found at the third binding site of the ruthenium(II)-η
6-p-cymene moiety depending on the conditions. [Ru(η
6-p-cymene)(L)(H
2O/Cl)] species are predominant at physiological pH in all studied cases. Hydrolysis of the aqua complex or the chlorido/hydroxido co-ligand exchange results in the formation of the mixed-hydroxido species [Ru(η
6-p-cymene)(L)(OH)] in the basic pH range. There is no indication for the decomposition of the mono-ligand complexes during 24 h in the ruthenium(II)-η
6-p-cymene-picolinic acid system between pH 3 and 11; however, a slight dissociation with a low reaction rate was found in the other two systems leading to the appearance of the dinuclear trihydroxido-bridged species [Ru
2(η
6-p- cymene)
2(OH)
3]
+ and free ligands at pH > 10. The replacement of the chlorido by an aqua ligand in [Ru(η
6-p- cymene)(L)Cl] was also monitored and equilibrium constants for the exchange process were determined.
- Organisation(s)
- Department of Inorganic Chemistry
- External organisation(s)
- University of Szeged, Hungarian Academy of Sciences, University of Auckland
- Journal
- Polyhedron
- Volume
- 67
- Pages
- 51-58
- No. of pages
- 8
- ISSN
- 0277-5387
- DOI
- https://doi.org/10.1016/j.poly.2013.08.057
- Publication date
- 01-2014
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 104003 Inorganic chemistry, 301305 Medical chemistry
- Keywords
- ASJC Scopus subject areas
- Materials Chemistry, Inorganic Chemistry, Physical and Theoretical Chemistry
- Sustainable Development Goals
- SDG 3 - Good Health and Well-being
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/ffc4ba6d-b511-4cb4-b871-a3e1b1ab04a4