Striking Difference in Antiproliferative Activity of Ruthenium- and Osmium-Nitrosyl Complexes with Azole Heterocycles

Author(s)
Gabriel Büchel, Anatolie Gavriluta, Maria Novak, Samuel Matthias Meier, Michael Jakupec, Olesea Cuzan, Constantin Turta, J.B. Tommasino, Erwann Jeanneau, Ghenadie Novitchi, Dominique Luneau, Vladimir Arion
Abstract

Ruthenium nitrosyl complexes of the general formulas (cation)(+)[cis-RuCL4(NO)(Hazole)](-), where (cation)(+) = (H(2)ind)(+), Hazole = 1H-indazole (Hind) (1c), (cation)(+) = (H(2)pz)(+), Hazole = 1H-pyrazole (Hpz) (2c), (cation)(+) = (H(2)bzim)(+), Hazole = 1H-benzimidazole (Hbzim) (3c), (cation)(+) = (H(2)im)(+), Hazole = 1H-imidazole (Him) (4c) and (cation)(+)[trans-RuCl4(NO)(Hazole)](-), where (cation)(+) = (H(2)ind)(+), Hazole = 1H-indazole (1t), (cation)(+) = (H(2)pz)(+), Hazole = 1H-pyrazole (2t), as well as osmium analogues of the general formulas (cation)(+)[cis-OsCl4(NO)(Hazole)](-), where (cation)(+) = (n-Bu4N)(+), Hazole = 1H-indazole (5c), 1H-pyrazole (6c), 1H-benzimidazole (7c), 1H-imidazole (8c), (cation)(+) = Na+; Hazole = 1H-indazole (9c), 1H-benzimidazole (10c), (cation)(+) = (H(2)ind)(+), Hazole = 1H-indazole (11c), (cation)(+) = H(2)pz(+), Hazole = 1H-pyrazole (12c), (cation)(+) = (H(2)im)(+), Hazole = 1H-imidazole (13c), and (cation)(+)[trans-OsCl4(NO)-(Hazole)](-), where (cation)(+) = n-Bu4N+, Hazole = 1H-indazole (5t), 1H-pyrazole (6t), (cation)(+) = Na+, Hazole = 1H-indazole (9t), (cation)(+) = (H(2)ind)(+), Hazole = 1H-indazole (11t), (cation)(+) = (H(2)pz)(+), Hazole = 1H-pyrazole (12t), have been synthesized. The compounds have been comprehensively characterized by elemental analysis, ESI mass spectrometry, spectroscopic techniques (IR, UV-vis, ID and 2D NMR) and X-ray crystallography (1c center dot CHCl3, 1t center dot CHCl3, 2t, 3c, 6c, 6t, 8c). The antiproliferative activity of water-soluble compounds (1c, it, 3c, 4c and 9c, 9t, 10c, 11c, lit, 12c, 12t, 13c) in the human cancer cell lines A549 (nonsmall cell lung carcinoma), CH1 (ovarian carcinoma), and SW480 (colon adenocarcinoma) has been assayed. The effects of metal (Ru vs Os), cis/trans isomerism, and azole heterocycle identity on cytotoxic potency and cell line selectivity have been elucidated. Ruthenium complexes (1c, 1t, 3c, and 4c) yielded IC50 values in the low micromolar concentration range. In contrast to most pairs of analogous ruthenium and osmium complexes known, they turned out to be considerably more cytotoxic than chemically related osmium complexes (9c, 9t, 10c, 11c, 11t, 12c, 12t, 13c). The IC50 values of Os/Ru homologs differ by factors (Os/Ru) of up to similar to 110 and similar to 410 in CH1 and SW480 cells, respectively. ESI-MS studies revealed that ascorbic acid may activate the ruthenium complexes leading to hydrolysis of one M-Cl bond, whereas the osmium analogues tend to be inert The interaction with myoglobin suggests nonselective adduct formation; i.e., proteins may act as carriers for these compounds.

Organisation(s)
Department of Inorganic Chemistry
External organisation(s)
Academy of Sciences of the Republic of Moldova, Université Joseph-Fourier (Grenoble-I), Université de Lyon
Journal
Inorganic Chemistry
Volume
52
Pages
6273-6285
No. of pages
13
ISSN
0020-1669
DOI
https://doi.org/10.1021/ic400555k
Publication date
2013
Peer reviewed
Yes
Austrian Fields of Science 2012
104003 Inorganic chemistry, 104022 Theoretical chemistry
Sustainable Development Goals
SDG 3 - Good Health and Well-being
Portal url
https://ucrisportal.univie.ac.at/en/publications/667d8572-b8e9-46c3-bef0-e7b63b6ddc89