2 4 Dinitrophenylhydrazine
Mostrando 1-12 de 17 artigos, teses e dissertações.
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1. Crystal Structure and Hirshfeld Surface Analysis of 1,4-Pentadien-3-one, (1E,4E)-1,5-diphenyl-2-(2,4-dinitrophenyl)hydrazone
The compound 1,4-pentadien-3-one,(1E,4E)-1,5-diphenyl-2-(2,4-dinitrophenyl)hydrazone presents the molecular formula C23H18N4O4 and was prepared in an undergraduate laboratory. The hydrazone was synthesized from the condensation between dibenzalacetone and 2,4-dinitrophenylhydrazine (DNPH) and crystallized employing water/acetone liquid-liquid diffusion. The
J. Braz. Chem. Soc.. Publicado em: 2021-02
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2. Color, phenolic and flavonoid content, and antioxidant activity of honey from Roraima, Brazil
The total phenolic and flavonoid content, color, and antioxidant activity were evaluated from ten honey samples from Apis mellifera L. collected from Roraima State, Brazil. The total phenolic content was determined using the Folin-Ciocalteu reagent and ranged from 250 to 548 mg gallic acid kg-1 of honey. The total flavonoid content was obtained using two met
Food Sci. Technol. Publicado em: 25/03/2014
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3. Determinação de 2,5-hexanodiona em urina empregando cromatografia líquida de alta eficiência, após derivatização com 2,4-dinitrofenil-hidrazina
A method for quantifying urinary 2,5-hexanedione was optimized and validated. Urine samples were hydrolyzed and derivatized with 2,4-dinitrophenylhydrazine. The analyte was separated in a high performance liquid chromatography system with a diode array detector, using a C18 column (150 x 4.6 mm, p.d. 5 µm) and a mobile phase composed of phosphate buffer pH
Química Nova. Publicado em: 2011
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4. DeterminaÃÃo dos teores do de carbamato de etila e de acroleÃna em aguardentes de cana produzidas em Minas Gerais / Determination of ethyl carbamate, acrolein in sugar cane spirits produced in Minas Gerais
Sugar cane spirit is obtained by means of natural fermentation process of the sugar cane juice, there being some critical points in the steps due to the presence of contaminant microorganisms and undesirable substances that can interfere in the production and the quality of the beverage. In addition to ethanol and water, the beverage contains in lesser conce
Publicado em: 2009
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5. Chemical characterization and antioxidant and citotoxic activities from alecrim propolis / Análise química e atividades antioxidante e citotóxica de amostras de própolis de alecrim
Propolis is a complex mixture of substances derived from bee products and plant resins. Propolis color and texture vary widely and chemical composition is dependent on the hive locality. Bees use propolis to seal openings in the hive and to line it internally, which help keeping the environment aseptic. Propolis properties in medicine has been known since an
Publicado em: 2008
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6. Compostos carbonílicos no ar em ambientes de trabalho de carvoarias na Bahia.
The goals of the present work were: to present an analytical methodology applicable to the determination of carbonyl compounds (CC) in vapor phase, in area and personal samples collected in charcoal company workplaces; to determine the CC profile in air inhaled by charcoal workers; and to quantify the CC in vapor phase in air of workplaces and breathing zone
Publicado em: 2005
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7. IDENTIFICATION OF A BACTERIAL GROWTH INHIBITOR FROM HELA CELLS: A KETOALDEHYDE
The growth-inhibiting factor found earlier in human cell cultures appeared to be a ketoaldehyde. An infrared spectral study of 2,4-dinitrophenylhydrazine derivatives suggested that the ketoaldehyde was 4-hydroxy-2-ketobutyraldehyde. The compound, when synthesized, gave the same DNPH derivatives as the natural substance.
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8. Evidence for methoxatin (pyrroloquinolinequinone) as the cofactor in bovine plasma amine oxidase from resonance Raman spectroscopy.
Resonance Raman spectra of the 2,4-dinitrophenylhydrazine derivatives of bovine plasma amine oxidase [amine:oxygen oxidoreductase (deaminating) (copper-containing), EC 1.4.3.6] have been measured. Detailed comparisons to the spectra of the corresponding derivatives of methoxatin (pyrroloquinolinequinone), pyridoxal, and other aldehydes and diones provide fur
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9. Mutagenicity and toxicity of carcinogenic and other hydrazine derivatives: correlation between toxic potency in animals and toxic potency in Salmonella typhimurium TA1538.
Eleven hydrazine derivatives and an aromatic amine were examined for mutagenicity and toxicity to Salmonella typhimurium. Phenylhydrazine, 2-nitrophenylhydrazine, 4-nitrophenylhydrazine, 2,4-dinitrophenylhydrazine, p-tolylhydrazine, and 4-nitroaniline were found to be frameshift mutagens (strain TA1538). Benzylhydrazine, m-hydroxybenzylhydrazine, p-hydrazino
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10. Role of Carbon Dioxide in Catabolism of Propane by “Nocardia paraffinicum” (Rhodococcus rhodochrous)
The catabolism of propane by “Nocardia paraffinicum” (Rhodococcus rhodochrous) has been shown to involve CO2 fixation after its oxidation to propionic acid. “N. paraffinicum” failed to grow on either propane or 1-propanol in the absence of CO2. The rate of propane utilization was directly related to the initial CO2 concentration, and Warburg respirom
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11. Oxidation of d(−) Lactate by the Electron Transport Fraction of Azotobacter vinelandii
d(−) Lactate oxidation in Azobacter vinelandii strain O is readily carried out by the membrane bound enzyme that concentrates in the electron transport fraction (R3). This oxidation in the R3 fraction is not dependent on externally added nicotinamide adenine dinucleotide, flavine adenine dinucleotide, or flavine mononucleotide. Phenazine methosulfate, O2,
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12. Bacterial oxidation of polyethylene glycol.
The metabolism of polyethylene glycol (PEG) was investigated with a synergistic, mixed culture of Flavobacterium and Pseudomonas species, which are individually unable to utilize PEGs. The PEG dehydrogenase linked with 2,6-dichlorophenolindophenol was found in the particulate fraction of sonic extracts and catalyzed the formation of a 2,4-dinitrophenylhydraz