Search results for "AMMONIA"
showing 10 items of 233 documents
Electrochemical reduction of the nitrite to ammonium ions in presence of [MoO2(O2CC(S)C6H5)2]2−
1995
Abstract Ammonia is formed during potentiostatic reduction of sodium nitrite solutions on the nafion-complex-coated electrode. When (NH4)2[MoO2(O2CC(S)(C6H5)2)2] is present in NaNO2 solutions a polarographic wave is associated to electrocatalytic reduction of nitrite ion. The wave height varies linearly on the concentration of nitrite ion, allowing a procedure for analysing this ion. This electrochemical behaviour distinguishes the nitrite from the nitrate ions. The Mo(VI), Mo(V), and Mo(IV) are involved in catalytic redox processes determining formation of NH4+ from nitrite ions.
Fluoro heterocycles. A photochemical methodology for the synthesis of 3-amino- and 3-(N-alkylamino)-5-perfluoroalkyl-1,2,4-oxadiazoles
2000
Abstract A photochemical methodology for the synthesis of perfluoroalkyl-1,2,4-oxadiazoles has been described. 3-Amino- and 3-( N -alkylamino)-5-perfluoroalkyl-1,2,4-oxadiazoles have been prepared by irradiation of 3-perfluoroalkanoylamino-4-phenyl-1,2,5-oxadiazoles (furazans) at λ =313 nm in methanol and in the presence of ammonia or primary aliphatic amines.
N-Substituierte Imidazole aus Aldehyden, 1,2-Diketonen, primären Aminen und flüssigem Ammoniak. 4. Mitt. über Imidazolsynthesen mit flüssigem Ammoniak
1974
N-substituierte Imidazole 5 konnen aus Aldehyden 1, 1,2-Diketonen 2 und primaren Aminen 3 in flussigem Ammoniak 4 dargestellt werden. N-substituted Imidazoles from Aldehydes, 1,2-Diketones, Primary Amines and Liquid Ammonia N-substituted imidazoles 5 can be synthesized from aldehydes 1, 1,2-diketones 2 and primary amines 3 in liquid ammonia 4.
Imidazol-4-carbinole aus Iminoestern und Dihydroxyaceton. 2. Mitt. über Imidazolsynthesen mit flüssigem Ammoniak
1974
Imidazol-4-carbinole 3 mit funktionellen Gruppen am C-Atom 2 lassen sich aus Iminoestern 1 und Dihydroxyaceton (2) in flussigem Ammoniak unter Druck darstellen. Imidazole-4-carbinols from Iminoesters and Dihydroxyacetone Imidazole-4-carbinols 3 with functional groups at C-atom 2 are obtained from iminoesters 1 and dihydroxyacetone (2) in liquid ammonia under pressure.
NMR-Spektroskopie an Heterocyclen, 6. Mitt. Favorskii-Umlagerung von α-Brom-β-methoxy-ketonen bei der Imidazol-Cyclisierung in flüssigem Ammoniak
1979
Bei der Imidazolsynthese aus α-Bromketonen und Formiminoethylester in flussigem Ammoniak werden α-alkylsubstituierte Buttersaure-Amide als Nebenprodukte erhalten, deren Entstehen einer Favorskii-Umlagerung zugeschrieben wird. Die isolierten Verbindungen wurden NMR-spektroskopisch untersucht. NMR Spectroscopy of Heterocycles. VI: Favorskii Rearrangement of α-Bromo-β-methoxy Ketones During Imidazole Cyclisation in Liquid Ammonia. During imidazole synthesis with α-bromo ketones and formiminic ethyl ester in liquid ammonia α-alkylbutyric amides were obtained as by-products. Their formation is attributed to a Favorskii rearrangement. The compounds were investigated by NMR spectroscopy.
Imidazole aus Aldehyden, 1,2-Diketonen und flüssigem Ammoniak. 3. Mitt. über Imidazolsynthesen mit flüssigem Ammoniak
1974
Bei der Darstellung von Imidazolen (3) aus aliphatischen oder aromatischen Aldehyden (1) und 1,2-Diketonen (2) in flussigem Ammoniak unter Druck konnen die verschiedenen Moglichkeiten der C-Substitution des Imidazolkerns realisiert werden. Imidazoles from Aldehydes, 1,2-Diketones and Liquid Ammonia If imidazoles (3) are prepared from aliphatic or aromatic aldehydes (1) and 1,2-diketones (2) in liquid ammonia under pressure, all possibilities of C-substitution of the imidazole nucleus can be realized.
Crystal structure of cis-bis(μ-β-alanine-κ2 O:O′)bis[trichloridorhenium(III)](Re–Re) sesquihydrate
2015
A dirhenium(III) cis-dicarboxylate complex is reported, which is representative of a small class of zwitterionic ammoniacarboxylato complexes involving a quadruple metal–metal bond.
Methionine Cycle Rewiring by Targeting miR-873-5p Modulates Ammonia Metabolism to Protect the Liver from Acetaminophen
2022
Drug-induced liver injury (DILI) development is commonly associated with acetaminophen (APAP) overdose, where glutathione scavenging leads to mitochondrial dysfunction and hepatocyte death. DILI is a severe disorder without effective late-stage treatment, since N-acetyl cysteine must be administered 8 h after overdose to be efficient. Ammonia homeostasis is altered during liver diseases and, during DILI, it is accompanied by decreased glycine N-methyltransferase (GNMT) expression and S-adenosylmethionine (AdoMet) levels that suggest a reduced methionine cycle. Anti-miR-873-5p treatment prevents cell death in primary hepatocytes and the appearance of necrotic areas in liver from APAP-adminis…
L‐Aspartate as a high‐quality nitrogen source in Escherichia coli : Regulation of L‐aspartase by the nitrogen regulatory system and interaction of L‐…
2020
Escherichia coli uses the C4-dicarboxylate transporter DcuA for L-aspartate/fumarate antiport, which results in the exploitation of L-aspartate for fumarate respiration under anaerobic conditions and for nitrogen assimilation under aerobic and anaerobic conditions. L-Aspartate represents a high-quality nitrogen source for assimilation. Nitrogen assimilation from L-aspartate required DcuA, and aspartase AspA to release ammonia. Ammonia is able to provide by established pathways the complete set of intracellular precursors (ammonia, L-aspartate, L-glutamate, and L-glutamine) for synthesizing amino acids, nucleotides, and amino sugars. AspA was regulated by a central regulator of nitrogen meta…
Molecular insights into shellac film coats from different aqueous shellac salt solutions and effect on disintegration of enteric-coated soft gelatin …
2014
The purpose of this investigation was to study the effect of using different salts of shellac on the disintegration properties of shellac-based enteric coatings. In the last two decades, shellac has been increasingly used as an aqueous solution for enteric coating purposes, with the ammonium salt being the form typically used. Little investigation has been performed on using other salts, and therefore, this was the focus of our work. Enteric coatings, based on different shellac salts (ammonium, sodium, potassium and composite ammonium-sodium), were applied onto soft gelatin capsules. Disintegration testing of the coated soft gelatin capsules showed that alkali metal salts promote faster dis…