Influence of wing-tip substituents and reaction conditions on the structure, properties and cytotoxicity of Ag(i)- and Au(i)-bis(NHC) complexes.
The formation of different conformers of dinuclear silver(i) and gold(i) 1,1'-(2-hydroxyethane-1,1-diyl) bridge-functionalized bis(NHC) complexes with various wing-tip substituents (R = methyl, isopropyl and mesityl) has been investigated using multinuclear NMR spectroscopy and SC-XRD as well as DFT calculations. The ratio of anti/syn isomers strongly depends both on wing-tip substituents and the metal. Moreover, the reaction temperature plays a significant role during the transmetallation process for the ratio of gold(i) conformers, which is further affected by purification procedures. All obtained Au(i)-bis(NHC) complexes have been applied in a standard MTT assay performed for screening the antiproliferative activity against human lung and liver cancer cells. Strong evidence for a significant influence of both wing-tip substituents and conformation on the cytotoxic properties of the applied complexes has been found.
Department of Chemistry and Catalysis Research Center, Molecular Catalysis, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany. fritz.kuehn@ch.tum.de.
Julia
http://orcid.org/0000-0002-1939-8819
J
Rieb
Department of Chemistry and Catalysis Research Center, Molecular Catalysis, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany. fritz.kuehn@ch.tum.de.
Bruno
B
Dominelli
Department of Chemistry and Catalysis Research Center, Molecular Catalysis, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany. fritz.kuehn@ch.tum.de.
David
D
Mayer
Catalysis Research Center, Technische Universität München, Ernst-Otto-Fischer Straße 1, D-85747 Garching bei München, Germany.
Christian
C
Jandl
Chair of Organic Chemistry II, Department of Chemistry, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching bei München, Germany.
Jonas
J
Drechsel
Chair of Organic Chemistry II, Department of Chemistry, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching bei München, Germany.
Wolfgang
W
Heydenreuter
Chair of Organic Chemistry II, Department of Chemistry, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching bei München, Germany.
Stephan A
SA
Sieber
Department of Chemistry and Catalysis Research Center, Molecular Catalysis, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany. fritz.kuehn@ch.tum.de.
Fritz E
http://orcid.org/0000-0002-4156-780X
FE
Kühn