Search results for "inorganic"

Speciation of dimethyltin(IV) – and trimethyltin(IV) – carbocysteinate and – glutamate systems in aqueous media

2008

The formation of complex species in the dimethyltin(IV) and trimethyltin(IV)-carboxymethyl-L-cysteinate (carbocysteinate) systems in NaClaq, at different ionic strengths, and in a multicomponent Na+, K+, Ca2+, Mg2+, Cl- and SO42- medium representative of the seawater major composition, is discussed. Experimental results give evidence for the formation of the following species (L¼carbocysteinate): [(CH3)2Sn(L)]0, [(CH3)2Sn(HL)]+, [(CH3)2Sn(OH)(L)]-, [(CH3)2Sn(OH)2(L)]2- in the DMT–CCYS system, and [(CH3)3Sn(HL)]0, [(CH3)3Sn(L)]- and [(CH3)3Sn(OH)(L)]2- in the TMT-CCYS system. The ionic strength dependence of formation constants was taken into account by an extended Debye Huckel type equation…

Potential use of organotin(IV)-tripetide complexes as stopper in tumor cells growth.

2008

Direct P-functionalization of azobenzene by a cationic phosphidozirconocene complex.

2016

International audience; We report that the cationic phosphidozirconocene complex [(eta(5)-C5H5)(2)Zr(PCy2)][CH3B(C6F5)(3)] (II) reacts with azobenzene, resulting in the expedient formation of Zr complex (2) bound to a tridentate PNN ligand. This reaction proceeds by a mechanism of cooperative nucleophilic substitution of hydrogen. The intermediate sigma(H) adduct (1) has been characterized by NMR spectroscopy.

DNA binding and biological activity of Cu(II) and Zn(II) complexes of a 2,5-diphenyl[1,3,4]oxadiazole macrocycle ligand.

2011

Carbon Dioxide Activation and Reaction Induced by Electron Transfer at an Oxide-Metal Interface

2015

A model system has been created to shuttle electrons through a metal-insulator-metal (MIM) structure to induce the formation of a CO2 anion radical from adsorbed gas-phase carbon dioxide that subsequently reacts to form an oxalate species. The process is completely reversible, and thus allows the elementary steps involved to be studied at the atomic level. The oxalate species at the MIM interface have been identified locally by scanning tunneling microscopy, chemically by IR spectroscopy, and their formation verified by density functional calculations.

An efficient method for selective oxidation of (oxime)Pt(II) to (oxime)Pt(IV) species using N,N-dichlorotosylamide

2016

The oxidation of (oxime)PtII species using the electrophilic chlorine-based oxidant N,N-dichlorotosylamide (4-CH3C6H4SO2NCl2) was studied. The reactions of trans-[PtCl2(oxime)2] (where oxime = acetoxime, cyclopentanone oxime, or acetaldoxime) with this oxidant led to trans-[PtCl4(oxime)2] products. The oxidation of trans-[Pt(o-OC6H4CH = NOH)2] at room temperature gave trans-[PtCl2(o-OC6H4CH = NOH)2], whereas the same reaction upon heating was accompanied by electrophilic substitution of the benzene rings. peerReviewed

1,1prime-Binaphthyl-2-methylpyridinium-based peroxophosphotungstate salts: synthesis, characterization, and their use as oxidation catalysts

2009

A series of 1,1′-binaphthyl-2-methylammonium and pyridinium salts 6, 7, and 8 was synthesized through the coupling reaction of 2-(bromomethyl)-1,1′-binaphthalene (5) with the dendritic tetraallyl pyridinedicarbinol dendron 2 as well as triethylamine and 4-tert-butylpyridine. Tetraallyl pyridinedicarbinol dendron 2 was prepared by allylation of commercially available diethyl pyridine-3,5-dicarboxylate (1). The allylation of 2 with allyltrimethylsilane in the presence of boron trifluoride was unsuccessful, as tetraallyl pyridinedicarbinol trifluoroboron adduct 3 was obtained instead of expected hexaallylpyridine compound 4. The catalytic hydrogenation of allyl groups of the ammonium salt of 2…

Reactions of m-Terphenyl-Stabilized Germylene and Stannylene with Water and Methanol: Oxidative Addition versus Arene Elimination and Different React…

2015

Reactions of the divalent germylene Ge(ArMe6)2 (ArMe6 = C6H3-2,6-{C6H2-2,4,6-(CH3)3}2) with water or methanol gave the Ge(IV) insertion product (ArMe6)2Ge(H)OH (1) or (ArMe6)2Ge(H)OMe (2), respectively. In contrast, its stannylene congener Sn(ArMe6)2 reacted with water or methanol to produce the Sn(II) species {ArMe6Sn(μ-OH)}2 (3) or {ArMe6Sn(μ-OMe)}2 (4), respectively, with elimination of ArMe6H. Compounds 1–4 were characterized by IR and NMR spectroscopy as well as by X-ray crystallography. Density functional theory calculations yielded mechanistic insight into the formation of (ArMe6)2Ge(H)OH and {ArMe6Sn(μ-OH)}2. The insertion of an m-terphenyl-stabilized germylene into the O–H bond was…

Preparation of a Series of “Ru(p-cymene)” Complexes with Different N-Heterocyclic Carbene Ligands for the Catalytic β-Alkylation of Secondary Alcohol…

2008

A series of five different “(p-cymene)Ru(NHC)” complexes (NHC = imidazolin-2-ylidene, imidazolin-4-ylidene, and pyrazolin-3-ylidene) have been obtained and fully characterized. The crystal structure of two of the new complexes has been determined by X-ray diffraction methods. All five complexes have been tested in the catalytic β-alkylation of secondary alcohols with primary alcohols and the dimerization of phenylacetylene, showing an excellent activity in both processes. A clear improvement on the catalytic activity of the complexes is observed when the more basic NHC ligands are used. The pyrazolylidene-Ru complex lies among the best catalysts for the β-alkylation of secondary alcohols re…

Oncogenic BRAF and p53 Interplay in Melanoma Cells and the Effects of the HDAC Inhibitor ITF2357 (Givinostat)

2023

Oncogenic BRAF mutations have been widely described in melanomas and promote tumour progression and chemoresistance. We previously provided evidence that the HDAC inhibitor ITF2357 (Givinostat) targets oncogenic BRAF in SK-MEL-28 and A375 melanoma cells. Here, we show that oncogenic BRAF localises to the nucleus of these cells, and the compound decreases BRAF levels in both the nuclear and cytosolic compartments. Although mutations in the tumour suppressor p53 gene are not equally frequent in melanomas compared to BRAF, the functional impairment of the p53 pathway may also contribute to melanoma development and aggressiveness. To understand whether oncogenic BRAF and p53 may cooperate, a po…