[(eta(6)-p-cymene)Ru(H2O)(3)](2+) binding capability of aminohydroxamates - A solution and solid state study

Authors: Parajdi-Losonczi, PL., Benyei, AC., Kovats, E., Timari, I., Muchova, TR., Novohradsky, V., Kasparkova, J., Buglyo, P.
Year: 2016


Complex forming capabilities of [(eta(6)-p-cymene)Ru(H2O)(3)](2+) with aminohydroxamates (2-amino-N-hydroxyacetamide (alpha-alahaH), 3-amino-N-hydroxypropanamide (beta-alahaH) and 4-amino-N-hydroxybutanamide (gamma-abhaH)) having the primary amino group in different chelatable position to the hydroxamic function were studied by pH-potentiometry, NMR and MS methods. Formation of stable [O,O] and mixed [O,O][N,N] chelated mono- and dinuclear species is detected in partially slow with alpha-alahaH and beta-alahaH or in fast processes with gamma-abhaH and the formation constants of the complexes present in aqueous solution are reported. Synthesis, spectral (NMR, IR) and ESI mass spectrometric characterization of novel dinuclear alpha-alaninehydroximato complexes containing the half-sandwich type Ru(II) core is described. The crystal and molecular structure of [{(eta(6)-p-cymene)Ru)(2)(mu(2)-alpha-alahaH(-1))(H2O)Br]Br center dot H2O (1) and [(eta(6)-p-cymene)Ru)(2)(mu(2)-alpha-alahaH(-1))(H2O)Cl]BF4 center dot H2O (2) was determined by single crystal X-ray diffraction method. In the complexes one half-sandwich core is coordinated by a hydroxamate [O,O] chelate while the other one by [N-amino,N-hydroxamate] fashion of the bridging ligand. In both cases the remaining coordination sites of one of the Ru cores are taken by a halide ion whiles the other one by a water molecule. Reaction of 2 with 9-methylguanine indicates the N7 coordination of this simple DNA model. Complexes 1 and 2 were tested for their in vitro cytotoxicity using human-derived cancer cell lines (A2780, MCF-7, SKOV-3, HCT-116, HeLa) and showed no anti-proliferative activity in the micromolar concentration range. (C) 2016 Elsevier Inc. All rights reserved.