Search results for "organometallic"
showing 10 items of 370 documents
Interesting synthetic routes from the reinvestigation of the reaction of the M(CO)6 (M=Cr, Mo and W) species with KOH
1989
Reinvestigation of the reaction of M(CO)6 (M=Cr, Mo or W) with KOH has been found to provide a very convenient route to the K[M2H(CO)10] compounds (M=Cr, Mo or W). The reaction involving Cr(CO)6 yields new potassium derivatives containing [Cr2(CO)10]2− and [HCr(CO)5]− species; also K[Cr2D(CO)10] is produced from the Cr(CO)6/KOD interaction in C2D5OD. The reaction involving two different group 6 metal carbonyls yields [MM′(CO)10(μ-H)]− (MM′=CrMo, CrW or WMo) species as their K+ and PPN+ [bis(triphenylphosphine)iminium] salts.
A novel pro-apoptotic role of zinc octacarboxyphthalocyanine in melanoma me45 cancer cell's photodynamic therapy (PDT)
2018
Abstract Zn-based phthalocyanine acts as drug or photosensitizer in photodynamic therapy (PDT) for the treatment of cancer cells. The activated zinc octacarboxyphthalocyanine (ZnPcOC) reacts with oxygen, to generate reactive oxygen species for the damage of melanoma cancer cells, Me45. This in vitro study aimed at investigating the cytotoxic effects of different concentrations of ZnPcOC activated with a diode laser (λ = 685 nm) on Me45, and normal human fibroblast cells, NHDF. To perform this study 104 cells/ml were seeded in 96-well plates and allowed to attach overnight, after which cells were treated with different concentrations of ZnPcOC (10, 20 and 30 μM). After 4 h, cells were irradi…
In Vitro and in Vivo Evaluation of Water-Soluble Iminophosphorane Ruthenium(II) Compounds. A Potential Chemotherapeutic Agent for Triple Negative Bre…
2014
A series of organometallic ruthenium(II) complexes containing iminophosphorane ligands have been synthesized and characterized. Cationic compounds with chloride as counterion are soluble in water (70–100 mg/mL). Most compounds (especially highly water-soluble 2) are more cytotoxic to a number of human cancer cell lines than cisplatin. Initial mechanistic studies indicate that the cell death type for these compounds is mainly through canonical or caspase-dependent apoptosis, nondependent on p53, and that the compounds do not interact with DNA or inhibit protease cathepsin B. In vivo experiments of 2 on MDA-MB-231 xenografts in NOD.CB17-Prkdc SCID/J mice showed an impressive tumor reduction (…
Probing the Paradigm of Promiscuity for N‐Heterocyclic Carbene Complexes and their Protein Adduct Formation
2021
Metal complexes can be considered a "paradigm of promiscuity" when it comes to their interactions with proteins. They often form adducts with a variety of donor atoms in an unselective manner. We have characterized the adducts formed between a series of isostructural N-heterocyclic carbene (NHC) complexes with Ru, Os, Rh, and Ir centers and the model protein hen egg white lysozyme by X-ray crystallography and mass spectrometry. Distinctive behavior for the metal compounds was observed with the more labile Ru and Rh complexes targeting mainly a surface l-histidine moiety through cleavage of p-cymene or NHC co-ligands, respectively. In contrast, the more inert Os and Ir derivatives were detec…
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…
On the Use of Metal Purine Derivatives (M=Ir, Rh) for the Selective Labeling of Nucleosides and Nucleotides
2014
The reactions of neutral or cationic IrIII and RhIII derivatives of phenyl purine nucleobases with unsymmetrical alkynes produce new metallacycles in a predictable manner, which allows for the incorporation of either photoactive (anthracene or pyrene) or electroactive (ferrocene) labels in the nucleotide or nucleoside moiety. The reported methodology (metalation of the purine derivative and subsequent marker insertion) could be used for the postfunctionalization and unambiguous labeling of oligonucleotides.
Complexes of organometallic compounds. XLVIII. Mössbauer and other studies on pyrazine derivatives of tin(IV) compounds. A relationship between isome…
1978
Abstract Adducts RSnCl 3 ·pyz (R = Me, Bu n , Oct n , Ph; pyz = pyrazine) have been synthesized and characterized in the solid state. It has been determined that RSnCl 3 ·pyz are polymeric compounds, where the ligand acts as bridging bis-monodentate and the tin atoms attain the coordination number six. This has been duduced from: i) temperature dependent Mossbauer spectroscopy; ii) the correlation between Mossbauer isomer shift, δ, and electrical charge on tin, Q Sn , concerning pyrazine adducts of RSnCl 3 and others; iii) an infrared study of the coordinated ligand in RSnCl 3 ·pyz. Other implications of the Mossbauer T dependent study ( e.g. , the decrease of the Debye temperature in RSnCl…
Novel ruthenium methylcyclopentadienyl complex bearing a bipyridine perfluorinated ligand shows strong activity towards colorectal cancer cells
2017
Three new compounds have been synthesized and completely characterized by analytical and spectroscopic techniques. The new bipyridine-perfluorinated ligand L1 and the new organometallic complex [Ru(η 5 -MeCp)(PPh 3 ) 2 Cl] (Ru1) crystalize in the centrosymmetric triclinic space group P1¯. Analysis of the phenotypic effects induced by both organometallic complexes Ru1 and [Ru(η 5 -MeCp)(PPh 3 )(L1)][CF 3 SO 3 ] (Ru2), on human colorectal cancer cells (SW480 and RKO) survival, showed that Ru2 has a potent anti-proliferative activity, 4–6 times higher than cisplatin, and induce apoptosis in these cells. Data obtained in a noncancerous cell line derived from normal colon epithelial cells (NCM46…
Factors affecting the amount and the mode of merocyanine 540 binding to the membrane of human erythrocytes. A comparison with the binding to leukemia…
1995
Abstract In the presence of albumin Merocyanine 540 (MC540) exhibits a very limited binding to the outer surface of the membrane of normal erythrocytes, whereas pronounced binding is observed to leukemia cells. To find out whether this difference is due to differences in the composition or structural organization of the cell membrane we analyzed effects of a number of covalent and non-covalent perturbations of the red cell membrane on the binding and fluorescence characteristics of membrane-bound MC540. It is shown that exposure of the cells to cationic chlorpromazine, neuraminidase or photodynamic treatment with AlPcS 4 as sensitizer caused a limited increase (30–50%) of MC540 binding, tog…
Electrochemical studies on organometallic compounds—xx. Electrogeneration of an unusual organometallic derivative of ruthenium(I)
1989
Abstract The two-electron reduction of dinuclear ruthenium complexes [RuCl 2 (η 6 - p -cymene)] 2 ( p -cymene = p -CH 3 C 6 H 4 CH(CH 3 ) 2 ] give the corresponding relatively stable ruthenium(I) dimer derivative. The same species can also be obtained by electrochemical reduction of the cationic complexes [(η 6 - p -cymene)Ru(μ-Cl) 3 Ru(η 6 - p -cymene)]PF 6 . A redox mechanism is proposed.