Search results for "gold complexe"
showing 6 items of 6 documents
New heteronuclear gold(I)-platinum(II) complexes with cytotoxic properties: are two metals better than one?
2014
A series of mono- and heterodinuclear gold(I) and platinum(II) complexes with a new bipyridylamine-phosphine ligand have been synthesized and characterized. The X-ray structures of the ligand precursor 4-iodo-N,N-di(pyridin-2-yl)benzamide, and of one gold derivative are reported. All the complexes display antiproliferative properties in vitro in human cancer cells in the range of cisplatin or higher, which appear to correlate with compounds' uptake. Interestingly, studies of the interactions of the compounds with models of DNA indicate different mechanisms of actions with respect to cisplatin. The biological activity study of these complexes provides useful information about the interest of…
Cyclometalated Au(III) Complexes for Cysteine Arylation in Zinc Finger Protein Domains: Towards Controlled Reductive Elimination
2019
With the aim of exploiting the use of organometallic species for the efficient modification of proteins through C-atom transfer, the gold-mediated cysteine arylation through a reductive elimination process occurring from the reaction of cyclometalated AuIII C^N complexes with a zinc finger peptide (Cys2His2 type) is here reported. Among the four selected AuIII cyclometalated compounds, the [Au(CCON)Cl2] complex featuring the 2-benzoylpyridine (CCON) scaffold was identified as the most prone to reductive elimination and Cys arylation in buffered aqueous solution (pH 7.4) at 37 °C by high-resolution LC electrospray ionization mass spectrometry. DFT and quantum mechanics/molecular mechanics (Q…
Exploring the Chemoselectivity towards Cysteine Arylation by Cyclometallated Au III Compounds: New Mechanistic Insights
2020
To gain more insight into the factors controlling the efficient cysteine arylation by cyclometalated Au(III) complexes, the reaction between selected gold compounds and different peptides was investigated by high‐resolution liquid chromatography electrospray ionization mass spectrometry (HR‐LC‐ESI‐MS). The deducted mechanisms of C–S cross‐coupling, also supported by density functional theory (DFT) and quantum mechanics/molecular mechanics (QM/MM) calculations, evidenced the key role of secondary peptidic gold binding sites in favouring the process of reductive elimination.
Weak aurophilic interactions in a series of Au(III) double salts.
2015
In this work, several new examples of rare AuIII⋯AuIII aurophilic contacts are reported. A series of gold(III) double salts and complexes, viz. [AuX2(L)][AuX4] (L = 2,2′-bipyridyl, X = Cl 1, Br 2; L = 2,2′-bipyrimidine, X = Cl 3, Br 4; L = 2,2′-dipyridylamine, X = Cl 5, Br 6), [AuX3(biq)] (biq = 2,2′-biquinoline, X = Cl 7, Br 8), [LH][AuX4] (L = 2,2′-bipyridyl, X = Cl 9; L = 2,2′-bipyrimidine, X = Cl 12; L = 2,2′-dipyridylamine, X = Cl 14, Br 15; L = 2,2′-biquinoline, X = Cl 17, Br 18), [AuBr2(bpy)]2[AuBr4][AuBr2] 10, [AuCl2(bpm)][AuCl2] 11, (bpmH)2[AuBr4][AuBr2] 13, and (dpaH)[AuBr2] 16 (1, 2, and 7 were reported earlier) was synthesized by coordination of a particular ligand to the AuIII …
Harnessing Fluorescence versus Phosphorescence Ratio via Ancillary Ligand Fine-Tuned MLCT Contribution
2016
A series of gold(I) alkynyl-diphosphine complexes (XC6H4C2Au)PPh2—spacer—PPh2(AuC2C6H4X); spacer = —C2(C6H4)nC2— (A1, n = 2, X = CF3; A2, n = 2, X = OMe; A3, n = 3, X = CF3; A4, n = 3, X = OMe), —(C6H4)n— (B5, n = 3, X = OMe; B6, n = 4, X = OMe) were prepared, and their photophysical properties were investigated. The luminescence behavior of the titled compounds is dominated by the diphosphine spacer, which serves as an emitting ππ* chromophore. The complexes exhibit dual emission, comprising low and high energy bands of triplet (phosphorescence) and singlet (fluorescence) origins, respectively. The electron-donating characteristics of ancillary groups X significantly affect the LLCT/MLCT c…
An Organometallic Gold(I) Bis‐N‐Heterocyclic Carbene Complex with Multimodal Activity in Ovarian Cancer Cells
2020
Abstract The organometallic AuI bis‐N‐heterocyclic carbene complex [Au(9‐methylcaffeine‐8‐ylidene)2]+ (AuTMX2) was previously shown to selectively and potently stabilise telomeric DNA G‐quadruplex (G4) structures. This study sheds light on the molecular reactivity and mode of action of AuTMX2 in the cellular context using mass spectrometry‐based methods, including shotgun proteomics in A2780 ovarian cancer cells. In contrast to other metal‐based anticancer agents, this organogold compound is less prone to form coordinative bonds with biological nucleophiles and is expected to exert its drug effects mainly by non‐covalent interactions. Global protein expression changes of treated cancer cell…