Search results for "diet"
showing 10 items of 4602 documents
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.
Effects of ultrasound-assisted extraction on physicochemical properties, bioactive compounds, and antioxidant capacity for the valorization of hybrid…
2021
Samples of tree hybrid mandarins (´Clemenvilla`, ´Ortanique` and ´Nadorcott`) were employed to determine the physicochemical properties (increase of conductivity, brix° and pH), bioactive compounds (total phenolic, flavonoid, ascorbic acid and carotenoids content) and antioxidant capacity (DPPH and TEAC) of peels. Mandarin peel extracts were prepared employing ultrasound assisted extraction (400 W, 80% v/v duty cycle, 40ºC). The results were compared to the values of control extraction method. Aqueous ethanol solution (50%, v/v) was used as solvent in solid-liquid ratio of 1:10 (w/v). A 5, 15 and 30 min were applied in both methods to stablish the most effective extraction time. The increas…
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…
Theory-based improvements of continuous polymer fractionation demonstrated for poly(carbonate)
1992
For the first time, a quantitative theoretical analysis (liquid/liquid phase equilibria treated by means of the continuous thermodynamics) of the operating characteristics of continuous polymer fractionation (CPF) was performed. The results of these calculations were compared with data published for CPF of polyethylene. It turned out that the efficiency of the conventional CPF corresponds to approximately two theoretical plates only. For this reason, several improvements, suggested by theoretical considerations, were realized experimentally, for which purpose the system dichloromethane/diethylene glycol/bisphenol-A polycarbonate was chosen. The pulsating sieve-bottom column was replaced by …
Metabolic effects of omega-3 fatty acids.
2001
Some metabolic effects of dietary marine oils, or of dietary eicosapentaenoic or docosahexaenoic acid are reviewed. It is pointed out that docosahexaenoic acid appears more effective as regards induction of peroxisomal beta-oxidation. Similarly, docosahexaenoic appears more powerful in terms of suppression of hepatic delta9-desaturase activity and mRNA-levels. The potential inhibitory effect of polyunsaturated fatty acids, particularly docosahexaenoic acid, on mitochondrial beta-oxidation is discussed. Experiments with rats suggesting that the hypolipidaemic response of eicosapentaenoic acid is more marked when the fatty acid was given to fed rats, as compared to fasted rats, are discussed.
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,…
Structural and magnetic studies of tetranuclear heterometallic M/Cr (M = Co, Mn) complexes self-assembled from zerovalent cobalt or manganese, Reinec…
2010
Abstract Four novel heterometallic complexes [Co2Cr2(NCS)4(HDea)2(Dea)2]·4dmf (1), [Co2Cr2(NCS)4(HDea)2(Dea)2]·4dmso (2), [Mn2Cr2(NCS)4(HDea)2(Dea)2(dmf)2]·2dmf (3) and [Mn2Cr2(NCS)4(HDea)2(Dea)2(dmso)2]·4dmso (4) have been prepared using zerovalent cobalt (1, 2) or manganese (3, 4), Reineckes salt, ammonium thiocyanate and a non-aqueous solution of diethanolamine (H2Dea) in air. The single X-ray analysis reveals that all compounds have similar centrosymmetric crystal structures based on a tetranuclear {M2Cr2(μ3-O)2(μ-O)4} (M = Co, Mn) core. Variable-temperature magnetic susceptibility measurements of 1, 2 and 4 show antiferromagnetic coupling between the magnetic centers, while 3 exhibits …
Synthese und Reaktionen der 3-O-Phosphoniogluco-und -allofuranosen
1982
Aus den bicyclischen Gluco- (3, 5, 7 und 9) und Allofuranosen 11 werden mit Triphenylphosphan (1), Azodicarbonsaure-diethylester (2) und Alkylierungs- oder Acylierungsmitteln isolierbare 3-O-Phosphoniokohlenhydrate (4, 6, 8, 10 und 12) hergestellt. Durch Erwarmen der allo-konfigurierten Salze 12 konnen an C-3 epimere gluco-konfigurierte Substitutionsprodukte in groser Vielfalt gewonnen werden. Die Reaktionen der gluco-konfigurierten Salze werden stark vom Charakter des einzufuhrenden Nucleophils und von Nachbargruppen im Kohlenhydratgerust beeinflust. Wahrend das Iodid 4a und das Azid 4g unter Substitution zum allo-Derivat 15 reagieren, tritt in den Fallen mit Bromid, Chlorid oder Sulfonat …
Unprecedented ring cleavage in the reaction of 1-methyl-3-phenacyl benzimidazolium ylide with diethyl azodicarboxylate
2010
The reaction with diethyl azodicarboxylate (DEAZD) of different cycloimmonium ylides derived from pyridinium, quinolinium, isoquinolinium and 1-methylbenzimidazolium bromides (3, 4, 5 and 6) yielded 3-substituted tetraazapentenes (2). In the special case of 1-methyl-3-phenacyl-benzimidazolium bromide (6a), the ring cleavage compound N-[1-[(ethoxycarbonyl)amino]-2-oxo-2-phenylethylidene]-N-formyl-N-methyl-1,2-benzenediamine (7a) was obtained. Its structure was established by X-ray crystallography.