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Formazan 3-amino

Aldehyde semicarbazones with two substituents on the terminal amino group (but not the hydrazino) (33) react with diazonium salts to yield N-carbamoyl-substituted formazans (34) (Eq. 4).47,48 A sulfonic acid deriva-... [Pg.215]

Other transition metals have received much less attention. Complexes of palladium and 2-amino-phenyl-containing formazans have been reported.397 Mercury complexes of tridentate formazans have been studied.398 Silver complexes of tridentate benzothiazolyl-containing formazans have also been studied.399 Recently, alkali and alkaline earth metals have been the subject of many studies. Formazans such as 228 and 229 as well as the macrocyclic 204 have received considerable attention as metal-specific analytical reagents.400-41 1... [Pg.271]

Mit Hydrazin erhalt man aus 1,3,4-Oxadiazolium-Salzen fiber isolierbare acyclische Zwischen-produkte sowohl 3-Amino-l,2,4-triazole, als auch 1,2-Dihydro-1,2,4.5-tetrazine746. Der Reaktionsverlauf wird wesentlich durch die Substituenten des 1,3,4-Oxadiazols und die Reaktionsbedingungen bestimmt. Beim Erhitzen mit Phenyl-hydrazin erhalt man als ringoffene Verbindung ein Hydrazin- und Formazan-Derivat746. [Pg.622]

Heating 4-amino-3-azido-4//-1,2,4-triazoles (229) in chlorobenzene to 110 °C gives the 3-amino-l,2,4,5-tetrazines (232). This reaction is explained by the intermediate formation of the nitrene (230) which opens to the formazane (231) and subsequent ring closure by nucleophilic attack of the hydrazono group on the nitrile function (66TL5369). [Pg.556]

Synthesis of the copper complex31 [167780-70-3] (H, Na salt) involves coupling of a diazonium compound with a hydrazone [54] 2-(3-amino-4-hydroxyphe-nylsulfonamido)chlorobenzene is dissolved in hot water, to which dilute NaOH solution is then added. After addition of sodium nitrite, the solution is cooled to -5 °C and then added to a well-stirred mixture of HC1, water, and ice. The diazonium salt suspension is neutralized with NaHC03 and combined with the weakly acidic solution of the hydrazone formed with 2-hydrazino-5-sulfobenzoic acid and benzaldehyde in water. The reaction mixture is kept at 0-10 °C, and at pH 10-12 by dropwise addition of diluted NaOH. When the coupling is complete, the pH of the formazan solution is reduced to 8 with HC1, a dilute aqueous solution of copper tetraaminosulfate is added and the solution is stirred for several hours. The copper complex 31 is precipitated at 85-90 °C with NaCl, then filtered and dried. The resulting powder colors wool in clear, fast blue tones. [Pg.318]

Function of mitochondria is also commonly monitored as an indicator of cellular toxicity. Mitochondrial uptake and retention of the fluorescent dye, rhodamine 123, can be visualized microscopically. Biochemical measurements of mitochondrial function include the ATP-ADP ratio and dehydrogenase activity with MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), which yields a colored formazan product upon reduction. The dye, neutral red (3-amino-7-dimethyl-amino-2-methylphenazine hydrochloride), targets lysosomes, and its retention is inversely related to cytotoxicity. Commercially available versions of the MTT and neutral red assays have been adapted to microtiter plate formats to provide highly efficient screening assays. Examples of how cell-type-specific functions can be followed as indicators of cell toxicity are included in Table 8.1. [Pg.141]

Indirect oxidation with tris-(4-bromophenyl)amine or 2,3-dihydro-2,2-dimethylphe-nothiazine-6(l/7)-one transforms formazane to tetrazolium, semicarbazones to 2-amino-1,3,4-oxadiazoles, benzaldehyde 2-pyridylhydrazones to 5-triazolo[4,3-a]pyridinium compounds, and phenyl 2-pyridyl ketone phenylhydrazone to 1/7-1,2,3-triazolo[3,4-a]-pyridi-nium compounds [123]. [Pg.681]

METAL COMPLEXES OF AZO DYES Metal complexes of certain 0,0 -dihydroxyazo, 0-carboxy-0 -hydroxyazo, o -amino-o hydroxyazo, arylazosalicyclic acid, and formazan compounds are used as dyes for wool, nylon, and cotton with generally much improved washfastness and lightfastness properties when compared to their respective unmetallized precursors. Dyes that are chelated with the metal on the substrate during the dyeing process are termed metallizable or mordant dyes. Conversely, those dyes that have been metallized by the dye manufacturer prior to use by the dyer, are classified as premetallized dyes. The two important types of premetallized dyes are the 1 1 and 2 1 complexes, eg, complexes with 1 1 and 2 1 ligand-to-metal ratios, respectively. [Pg.436]

Difficulties of this sort have been reported, e.g., in the extraction of phenols which had been converted to azo dyes on the adsorbent layer [623]. The reaction of sulphonamides with a diazonium reagent has been taken to completion by adding excess reagent again after having extracted the coloured product [69]. The determination of monosaccharides with benzidine-glacial acetic acid has been carried out similarly [38]. The method has been used also for the quantitative analysis of amino acids, after colour reaction with ninhydrin [42, 95] corticosteroids, after reaction yielding formazans [64] and of cannabinols after conversion into azo compounds [370]. [Pg.154]

CnHnCIH. C-Amino-N-phenyl-II -r4-ohlor- en ]-formazan 16 II13. [Pg.750]

Syntheses of amino-alditol derivatives are covered in Chapters 18 and 19, and the introduction of a 2-acetamido-function into a sugar formazan derivative is covered in Chapter 10. [Pg.97]


See other pages where Formazan 3-amino is mentioned: [Pg.248]    [Pg.249]    [Pg.217]    [Pg.265]    [Pg.46]    [Pg.318]    [Pg.134]    [Pg.552]    [Pg.106]    [Pg.68]    [Pg.77]    [Pg.402]    [Pg.337]    [Pg.438]    [Pg.543]    [Pg.327]    [Pg.7187]    [Pg.7204]    [Pg.515]    [Pg.14]    [Pg.9]    [Pg.245]   
See also in sourсe #XX -- [ Pg.263 ]




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