Search results for "RIAM"

ChemInform Abstract: Review: Solution Equilibria of Ternary Complexes Formed from Copper(II), Aliphatic Amines, and Bioligands

2014

This review provides a summary of the coordination chemistry of ligands in the ternary system: copper(II)–aliphatic amine–bioligand, where amine = ethylenediamine – En, diethylenetriamine – Dien, or N, N, N′, N″, N″-pentamethyldiethylenetriamine – Me5dien, and bioligand = selected amino acid, aminohydroxamic acid, or aminophosphonic acid, in aqueous solution. We would like to show the specific interactions of copper(II) in ternary systems in the context of complex equilibria chemistry.

Boehmite Supported Pyrene Polyamine Systems as Probes for Iodide Recognition

2013

New organic–inorganic fluorescent probes made by attaching the tripodal polyamine (tris(2-aminoethyl))amine (tren), propylamine, or diethylenetriamine functionalized with pyrene as a fluorophore to an γ-aluminum oxohydroxide matrix have been prepared and studied both in solution and supported on the surface of boehmite nanoparticles. Both kinds of systems have been revealed as sensitive and selective fluorescence turn-off chemosensors for iodide in aqueous solution with an estimated detection limit that reaches 36 ppb. The recognition characteristics and photophysical properties of these molecules are essentially preserved when they are grafted to the surface of the particles. Since the nan…

CuIIand ZnIICoordination Chemistry of Pyrazole‐Containing Polyamine Receptors − Influence of the Hydrocarbon Side Chain Length on the Metal Coordinat…

2004

The synthesis of a new macrocyclic receptor (L 4 ) containing two 3,5-dimethylpyrazole units connected by dipropylenetriamine bridges is reported for the first time; pH-metric titrations indicate that L 4 shows six protonation steps in the pH range 2-11. In the absence of metal ions, the pyrazole moieties are not involved in acid-base processes in this pH range. Addition of Cu I I and Zn I I results in deprotonation of the pyrazole moieties which act as bis(monodentate) η 1 :η 1 ligands. This induced deprotonation occurs at higher pH values than in the complexes of the analogous ligand containing diethylenetriamine bridges (L 1 ). The crystal structures of [Cu 2 (H - 2 L 4 )](ClO 4 ) 2 and …

Novel malonate-containing coordination compounds with ligands having N-And NO-donors: Synthesis, structures, and magnetic properties

2012

In our efforts to tune the structures of mixed-ligands malonate-containing coordination compounds, four copper(II) and two high-spin cobalt(II) complexes of formulas [Cu(mal)(H 2O)(dpo)] n (1), [Cu 2(mal) 2(H 2O) 2(dpp)] n · 7nH 2O (2), [Cu 2(mal) 2(H 2O) 2-(bpe)] n · 2nH 2O (3), {[Cu(mal) 2(H 2O) 2][Cu(dien)]} n · 4nH 2O (4)[Co 2(mal) 2(H 2O) 6(dpo)] ·2H 2O(5) and [Co(mal)(H 2O)(phen)] n · 2nH 2O (6) [H 2mal = malonic acid, dpo =4,4'-bipyridine-N,N'-dioxide, dpp = 2,3-bis(pyridyl)pyrazine, bpe =1,2-bis(4-pyridyl)ethylene, dien = diethylenetriamine and phen = 1,10-phenanthroline] have been synthesized and structurally characterized by X-ray diffraction on single crystals. Complexes 1, 2, 4,…

Review: Solution equilibria of ternary complexes formed from copper(II), aliphatic amines, and bioligands

2014

This review provides a summary of the coordination chemistry of ligands in the ternary system: copper(II)–aliphatic amine–bioligand, where amine = ethylenediamine – En, diethylenetriamine – Dien, or N, N, N′, N″, N″-pentamethyldiethylenetriamine – Me5dien, and bioligand = selected amino acid, aminohydroxamic acid, or aminophosphonic acid, in aqueous solution. We would like to show the specific interactions of copper(II) in ternary systems in the context of complex equilibria chemistry.

Efficient Synthesis of 1,4,7-Triazacyclononane and 1,4,7-Triazacyclononane-Based Bifunctional Chelators for Bioconjugation

2014

The reaction of diethylenetriamine with chloroacetaldehyde yielded a bicyclic aminal intermediate for the synthesis of 1,4,7-triazacyclononane (TACN), a macrocyclic polyamine the derivatives of which find applications as catalysts, bleaching agents, and chelators for medical imaging. This new synthetic protocol outperforms the synthetic methods described so far because it does not involve any cyclization step. Moreover, this aminal intermediate allowed access to a new family of TACN derivatives functionalized on the carbon skeleton, for example, C-aminomethyl-TACN. This novel compound is a precursor of valuable bifunctional chelating agents for nuclear medicine, in particular, for the prepa…

Synthesis of azamacrocycles via a Mitsunobu reaction

2005

Reaction of pernosylated diethylenetriamine and 2-substituted propane-1,3-diols in dry THF in the presence of triphenylphosphine and diisopropyl azodicarboxylate gives the corresponding protected 9-substituted 1,4,7-triazacyclodecanes. The Mitsunobu reaction was also used in the preparation of 3-substituted 1,5,9-triazacyclododecanes and macrocyclic pyridine derivatives.

1983

Water soluble polyamides with iminoethylene and oxyethylene units in the main chain were obtained by condensation polymerization of diethylenetriamine and triethylenetetramine with suitable dimethylesters containing two or three oxyethylene units. The molecular weights were in the range of Mn = 5000–7000. By potentiometric and conductometric titration only 80–85% of the expected amount of basic groups was found which was probably caused by branching. Durch Polykondensation von Diethylentriamin und Triethylentetramin mit Dimethylestern von Sauren, die zwei oder drei Oxyethyleneinheiten enthalten, wurden wasserlosliche Polyamide mit Iminoethylen- und Oxyethyleneinheiten in der Hauptkette erha…

¿Quién decide qué y cómo? el conflicto en torno a la participación ciudadana en el contexto del desarrollo de la iniciativa urbana: Cuenca-San Antón …

2018

This article describes the main results of an ethnographic study on citizen participation carried out in the context of the development of the Urban Initiative (2007-2015): Cuenca-Barrio de San Antón. Managed by the City Council of Cuenca and financed by the European Regional Development Funds (FEDER) under the Ministry of Economy and Finance at the Government of Spain The results of the research show how in the context of the application of neoliberal policies, citizen participation becomes the trigger for new conflicts between institutions and citizens. In this sense, it is worth noting how, in practice, institutions in their capacity as experts and not willing to dis-empower themselves, …

6-Amino-2-iminiumyl-4-oxo-1,2,3,4-tetrahydropyrimidin-5-aminium sulfate monohydrate

2019

The title compound, C4H9N5O2+·SO4 2−·H2O, is the monohydrate of the commercially available compound `C4H7N5O·H2SO4·xH2O'. It is obtained by reprecipitation of C4H7N5O·H2SO4·xH2O from dilute sodium hydroxide solution with dilute sulfuric acid. The crystal structure of anhydrous 2,4,5-triamino-1,6-dihydropyrimidin-6-one sulfate is known, although called by the authors 5-amminium-6-amino-isocytosinium sulfate [Bieri et al. (1993). Private communication (refcode HACDEU). CCDC, Cambridge, England]. In the structure, the sulfate group is deprotonated, whereas one of the amino groups is protonated (R 2C—NH3 +) and one is rearranged to a protonated imine group (R 2C=NH2 +). This arrangement is very…