Glyoxal-bis

Glyoxal bis(2-hydroxyanil) [1149-16-2] M 240.3, m 210-213", e294nm 9880. Crystd from MeOH or EtOH. 

Bis(thiosemicarbazones) [89-97] and AT-heterocyclic thiosemicarbazones comprise two interesting series of experimental chemotherapeutic agents. 2-formylpyridine thiosemicarbazone, the first of the latter series to be examined for biological activity, showed mild antileukemic activity against 1-1210 tumor in mice [98]. However, it was found to be toxic at the therapeutic dose levels which led to synthesis of other aromatic and heterocyclic thiosemicarbazones as potential agents [80, 99, 100]. However, the only active anticancer compounds besides glyoxal bis(thiosemicarbazones) were the iV-heterocyclic thiosemicarbazones [101], 2 formyl-3-hydroxypyridine thiosemicarbazone [102] and... 

Analysis. Ca gives a brick-red flame coloration, indicating that various optical spectroscopies will be effective in its determination. Ca is quantitatively determined by colorimetry down to 100 ppb using murexide or o-cresolphthalein, by atomic absorption spectroscopy (AAS) to 20 ppb, to 1 ppb by electrothermal absorption spectroscopy (ETAS), to 0.01 ppb by inductively-coupled plasma emission spectroscopy (ICPES), and to 10 ppb by inductively-coupled plasma mass spectroscopy (ICPMS). A spot test for Ca which extends to 3 ppm is provided by glyoxal bis(2-hydroxyanil). 

Im Gegensatz dazu unterliegt Diphenyl-glyoxal-bis-oxim in Polyphosphorsaure bei 120° und einer Reaktionszeit von 12 Minuten einer Beckmann-Umlagerung in fast quantitativer Ausbeute zu 3,5-Diphenyl-l,2,4-oxadiazol200 ... 

Durch Oxidation von Glyoxal-bis-iminen sind a-Hydroximino-carbonsaure-nitriloxide zugang-lich, die fiber die instabilen a-Hydroximino-isocyanate als Zwischenprodukte zu 5-Hydroxy-1,2,4-oxadiazolen cyclisieren198,343 z. B. ... 

Das aus Phenyl-glyoxal-bis-oxim mit einem Aquivalent Acetanhydrid zugangliche 3-Phenyl-furazan (87%)318 wird in heiflem Acetanhydrid zu Acetoximino-phenyl-acetonitril umgesetzt318 ... 

Nickerson, T. A., Moore, E. E. and Zimmer, A. A. 1964. Spectrophotometric determination of calcium in milk using 2,2 -(ethanediylidene-dinitrilo) diphenol (glyoxal bis (2-hydroxyanil). Anal. Chem. 36, 1676-1677. 

Treatment of methyl sulfoxide solutions of D-mannose or other sugar phenylhydrazones or melibiose phenylosazone with potassium tert-butoxide and a trace of oxygen at room temperature showed no evidence of the paramagnetic species characteristic of glyoxal bis(phenylhydra-... 

The key question for such species is whether two imine groups will provide intramolecular stabilization or destabilization. There are three examples of these species for which there are relevant thermochemical data 70a, the conjugated glyoxal bis-imine,, BuN=CI ICI I=NBu (see Reference 153) 70b, the cyclic and likewise conjugated... 

Glycosyl halides, reaction with ethyl potassium dithiocarbonates, 111 —, poly-O-acetyl-, solvolysis of, 39 Glyculosonic acids, 3-deoxy-, 253, 254 Glyoxal, bis(phenylhydrazone), 81 Guanosine, 5-(fucosyl dihydrogen pyrophosphate), 205 5-phosphate, 227 trihydrogen pyrophosphate, 205 —, 2-deoxy-, 5-triphosphate, 231 Guaran, 71, 75... 

Reaction of the dialdehyde with phenylhydrazine gave a derivative which formed an amorphous diphenylformazan (which, further, gave a monoacetate). Structure (55) was proposed for the formazan. Reaction of the dialdehyde with (p-nitrophenyl) hydrazine gave an amorphous mono-hydrazone, which was hydrolyzed by acid to glyoxal bis[(p-nitrophenyl)-hydrazone) and glycerose (as pyruvaldehyde). Structure (56) was assigned... 

Von den weiteren vielzahnigen Chelatbildnern soil liier noch das Glyoxal-bis-(2-hydroxy-anil) (GBIIA) erwahnt werden, das mit UO + und... 

Polycondensation of di- and triaminothiophenol with glyoxal results in the formation of resins containing glyoxal-bis-2-mercaptoanil ... 

Glyoxal bis(2-hydroxyanil) is often used for the determination of calcium either in aqueous media or after extraction. A sensitive method involving the Chlorophosphonazo III has been described. 

Glyoxal bis(2-hydroxyanil) (GBHA, formula 14.2) forms a sparingly soluble red complex with calcium in alkaline media. The compound dissolves in aqueous methanol (1 + 1) media by the substitution of two molecules of methanol for the two water molecules co-ordinatively bonded to the calcium. 

Glyoxal bis(2-hydroxyanil) (GBHA), 0.05% solution in methanol. Solutions more than a week old must be discarded. 

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