RESUMEN
As a dimetal-binding rigid scaffold, 2-(pyridin-2-yl)imidazo[1,5-b]pyridazine-7-ylidene was introduced. The scaffold was first converted into a meridional Au,N,N-tridentate ligand through binding of a Au(I)Cl moiety at the carbene center. The Au(I) center and the N,N-chelating moiety were expected to function as metallophilic and 4e-σ-donative interaction sites, respectively, in the binding of the second metal center. In this manner, various trinuclear heterobimetallic complexes were synthesized with different 3d-metal sources, such as cationic CuI , CuII , NiII , and CoII salts. SC-XRD analysis showed that the mono-3d-metal di-gold(I) trinuclear heterobimetallic complexes were constructed through gold(I)-metal interactions. Metallophilic interactions were also investigated by quantum chemical calculations including the AIM and IGMH methods.
RESUMEN
The crystal structure of the title mol-ecular complex, [Ag2{VO2F2}2(C13H17N3O2)4]·4H2O, supported by the heterofunctional ligand tr-ad-COOH [1-(1,2,4-triazol-4-yl)-3-carb-oxy-adamantane] is reported. Four 1,2,4-triazole groups of the ligand link two AgI atoms, as well as AgI and VV centres, forming the heterobimetallic coordination cluster {AgI 2(VVO2F2)2(tr)4}. VV exists as a vanadium oxofluoride anion and possesses a distorted trigonal-bipyramidal coordination environment [VO2F2N]. A carb-oxy-lic acid functional group of the ligand stays in a neutral form and is involved in hydrogen bonding with solvent water mol-ecules and VO2F2 - ions of adjacent mol-ecules. The extended hydrogen-bonding network is responsible for the crystal packing in the structure.
RESUMEN
Formation of PdIn intermetallic nanoparticles supported on α-Al2O3 was investigated by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and hydrogen temperature-programmed desorption (H2-TPD) methods. The metals were loaded as heterobimetallic Pd(µ-O2CMe)4In(O2CMe) complex to ensure intimate contact between Pd and In. Reduction in H2 at 200 °C resulted in Pd-rich PdIn alloy as evidenced by XRD and the disappearance of Pd hydride. A minor amount of Pd1In1 intermetallic phase appeared after reduction at 200 °C and its formation was accomplished at 400 °C. Neither monometallic Pd or in nor other intermetallic structures were found after reduction at 400â»600 °C. Catalytic performance of Pd1In1/α-Al2O3 was studied in the selective liquid-phase diphenylacetylene (DPA) hydrogenation. It was found that the reaction rate of undesired alkene hydrogenation is strongly reduced on Pd1In1 nanoparticles enabling effective kinetic control of the hydrogenation, and the catalyst demonstrated excellent selectivity to alkene.
RESUMEN
Emerging studies have shown that mitochondrial DNA (mtDNA) is an attractive target for anticancer therapeutics. Herein, a heterobimetallic complex [Ru(dip)2 (µ-bpm)PtCl2 ]Cl2 (RuPt; dip=4,7-diphenyl-1,10-phenanthroline; bpm=2,2'-bipyrimidine) and the corresponding mononuclear complex [Ru(dip)2 (bpm)]Cl2 (Ru) have been designed and synthesized. RuPt can bind to mtDNA and damage it both in the dark and upon visible light irradiation. By using a variety of methods, it was demonstrated that RuPt can interfere with the function of mtDNA by decreasing the amplification and copy number of mtDNA, and affecting the transcriptional level of mitochondria-encoded genes. Furthermore, RuPt can disturb the physiological processes of mitochondria and induce caspase-dependent apoptosis in the presence of light. In addition, RuPt shows low systemic toxicity and potent in vivo anticancer potency upon light irradiation. This study provides strong evidence that mtDNA is an important molecular target of RuPt, and photodamaging mtDNA is an effective strategy to overcome cisplatin resistance.
Asunto(s)
Daño del ADN/efectos de los fármacos , ADN Mitocondrial/genética , Neoplasias/tratamiento farmacológico , Compuestos Organoplatinos/farmacología , Fármacos Fotosensibilizantes/farmacología , Rutenio/farmacología , Células A549 , Antineoplásicos/química , Antineoplásicos/farmacología , Cisplatino/química , Cisplatino/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Células HeLa , Humanos , Neoplasias/genética , Compuestos Organoplatinos/química , Fenantrolinas/química , Fenantrolinas/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/química , Pirimidinas/química , Pirimidinas/farmacología , Rutenio/químicaRESUMEN
The title ion-association metal complex, [Li(C4H8O)4]2[Mg2(C43H61O3)2], has been synthesized from the tridentate phenolic ligand tris-(3,5-di-tert-butyl-2-hy-droxy-phen-yl)methane in tetra-hydro-furan (THF). The aryl-oxo magnesiate complex anion is binuclear with each Mg2O4 complex unit inversion-related and bridged through the two tridentate chelating phenolate O-donors of the ligand. The complex centres have a distorted tetra-hedral stereochemistry [Mg-O range 1.8796â (17)-2.0005â (16)â Å] and an Mgâ¯Mg separation of 2.9430â (14)â Å]. The LiO4 coodination sphere of the cation comprises four THF O-donor atoms and has a slightly distorted tetra-hedral conformation [Li-O range 1.899â (5)- 1.953â (5)â Å]. In the crystal, a number of stabilizing intra-anion C-Hâ¯O hydrogen-bonding inter-actions are present but no inter-species associations are found.
RESUMEN
The strikingly different reactivity of a series of homo- and heterodinuclear [(MIII )(µ-O)2 (MIII )']2+ (M=Ni; M'=Fe, Co, Ni and M=M'=Co) complexes with ß-diketiminate ligands in electrophilic and nucleophilic oxidation reactions is reported, and can be correlated to the spectroscopic features of the [(MIII )(µ-O)2 (MIII )']2+ core. In particular, the unprecedented nucleophilic reactivity of the symmetric [NiIII (µ-O)2 NiIII ]2+ complex and the decay of the asymmetric [NiIII (µ-O)2 CoIII ]2+ core through aromatic hydroxylation reactions represent a new domain for high-valent bis(µ-oxido)dimetal reactivity.