Search results for "COPP"

Ligand entrapment in twofold interpenetrating PtS matrixes by metallo-organic frameworks.

2003

Single-crystal X-ray crystallography was used to determine the structures of four metallo-organic frameworks (MOFs). A dendritic tetradentate ligand (tetrakis(isonicotinoxymethyl)methane, TINM) was used with first-row transition-metal elements copper, nickel, and cobalt to synthesize MOFs with a PtS interpenetration, due to both planar and tetrahedral junctions being present in the framework. Two different polymeric complexes, 1 and 2, were obtained from similar starting materials, TINM and Cu(NO(3))(2).3H(2)O, but different solvents. The use of dichloromethane in addition to methanol and water promoted the coordination of nitrate ions to the copper. With only methanol and water used as sol…

2-Organoselenomethyl-1H-benzimidazole Complexes of Copper(II) and Copper(I)

2009

Structurally characterized 2-methylselenomethyl-1H-benzimidazole (msbi) is shown to form complexes in 2:1 ratio with copper(II). Whereas the central cation [Cu(msbi)2Cl]+ = 1+ in [Cu(msbi)2Cl]Cl·2MeOH crystallizes in an approximately mixed square-pyramidal/trigonal-bipyramidal structure (τ = 0.52) with the second and third row atoms chlorine and selenium in the equatorial plane, the related [Cu(msbi)2(MeOH)](BF4)2 = [2](BF4)2 exhibits a closer to square-pyramidal arrangement with τ = 0.36 for that complex dication 22+. In both cases, the Cu–N bonds are short at about 1.94 A, whereas the Cu–Se distances vary between 2.62 A for 1+ and ca. 2.54 A for 22+. Slight differences between the Jahn–Te…

Ligand mediated structural diversity of copper(II)-azido moiety: Synthesis, structure and magnetic study

2022

Abstract Two copper azido complexes [Cu4(L1)4(µ1,1-N3)3(N3)] (1) and [{Cu2(L2)(N-benzylen)(µ1,1-N3)3(µ1,1,3-N3(N3)]n (2) have been synthesized by the reaction of aqueous solution of sodium azide to a methanolic solution of copper perchlorate hexahydrate and corresponding Schiff-base ligands. Schiff bases HL1 and HL2 act as blocking coligands are derived from the 1:1 condensation of N-benzyl ethylenediamine with Salicyldehyde and 2-hydroxy-5-chloroacetophenone respectively (N-benzylen is the N-benzyl ethylenediamine). These two complexes are characterized by the elemental analysis, FT-IR, single crystal X-ray diffraction, powder XRD and also TGA. Single crystal X-ray structural study reveals…

Potential biological role of laccase from the sponge Suberites domuncula as an antibacterial defense component

2014

Abstract Background Laccases are copper-containing enzymes that catalyze the oxidation of a wide variety of phenolic substrates. Methods We describe the first poriferan laccase from the marine demosponge Suberites domuncula. Results This enzyme comprises three characteristic multicopper oxidase homologous domains. Immunohistological studies revealed that the highest expression of the laccase is in the surface zone of the animals. The expression level of the laccase gene is strongly upregulated after exposure of the animals to the bacterial endotoxin lipopolysaccharide. To allow the binding of the recombinant enzyme to ferromagnetic nanoparticles, a recombinant laccase was prepared which con…

Copper-catalyzed click reactions: quantification of retained copper using 64Cu-spiked Cu(I), exemplified for CuAAC reactions on liposomes

2018

Abstract The Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is a powerful, highly reliable and selective reaction which allows for a rapid synthesis in high yields and under mild conditions (pH, temperature). However, the cytotoxicity of copper requires its complete removal prior to an application in vivo. This is an issue especially when it comes to CuAAC reactions on macromolecular structures or drug delivery systems, as copper might be retained by these systems. Thus, a quantification of the final copper content of these systems is inevitable, which we exemplified for a CuAAC reaction on liposomes using 64Cu-spiked Cu(I). In this respect, a Cu(II) nitrate solution was irradiated at t…

Determinazione di costanti di formazione di coppie ioniche in liquidi ionici

Studio spettrofotometrico della formazione di coppie ioniche ammina/p-nitrofenolo in liquido ionico

Gold nanostars co-coated with the Cu(II) complex of a tetraazamacrocyclic ligand

2015

The twelve-membered tetraazamacrocyclic ligand L1 bears an appended lipoic acid unit, whose disulphide ring is an efficient grafting moiety for the surface of gold nanostars (GNS). The GNS that were used featured a localized surface plasmon resonance (LSPR) absorption at ∼800 nm, i.e. in the near infrared (NIR). We investigated different approaches for coating them with the Cu(2+) complex of L1. While the direct reaction of [CuL1](2+) with as-prepared GNS led to aggregation, an initial coating step with polyethyleneglycol-thiol (PEG-SH) was found to be advantageous. Displacement reactions were carried out on pegylated GNS either with [CuL1](2+), directly generating [Cun(L1@GNS)](2n+), or wi…

Osteonecrosis detected by whole body magnetic resonance (WB-MRI) in patients with Hodgkin lymphoma treated by BEACOPP

2016

Purpose: The purpose of our retrospective study was to assess the incidence of osteonecrosis in patients who received different chemotherapies. Methods and Materials: We evaluated the Whole Body Magnetic Resonance (WB-MRI) scans performed on 42 patients with Hodgkin Lymphoma treated by three chemotherapy regimens (6 ABVD, 2 ABVD + 4 BEACOPP, 2 ABVD + 8 BEACOPP), excluding the patients with main risk factors for osteonecrosis. Results: Six out of 7 patients (85.7%) who received 8 BEACOPP and 1 out of 5 patients (20%) treated by 4 BEACOPP presented osteonecrosis, with a statistically significant difference of frequency between the two groups of patients (p<0.05); no injury has been reporte…

Di- and Tetrairon(III) μ-Oxido Complexes of an N3S-Donor Ligand: Catalyst Precursors for Alkene Oxidations

2019

The new di- and tetranuclear Fe(III) μ-oxido complexes [Fe 4 (μ-O) 4 (PTEBIA) 4 ](CF 3 SO 3 ) 4 (CH 3 CN) 2 ] (1a), [Fe 2 (μ-O)Cl 2 (PTEBIA) 2 ](CF 3 SO 3 ) 2 (1b), and [Fe 2 (μ-O)(HCOO) 2 (PTEBIA) 2 ](ClO 4 ) 2 (MeOH) (2) were prepared from the sulfur-containing ligand (2-((2,4-dimethylphenyl)thio)-N,N-bis ((1-methyl-benzimidazol-2-yl)methyl)ethanamine (PTEBIA). The tetrairon complex 1a features four μ-oxido bridges, while in dinuclear 1b, the sulfur moiety of the ligand occupies one of the six coordination sites of each Fe(III) ion with a long Fe-S distance of 2.814(6) A. In 2, two Fe(III) centers are bridged by one oxido and two formate units, the latter likely formed by methanol oxidati…