Dimethyl aminoazobenzene

Dansyl chloride (5-dimethylaminonaphthlene-l-sulphonyl chloride) and the related dabsyl chloride (4-dimethyl-aminoazobenzene-4 -sulphonyl chloride) have also been used. Sensitivity of the latter method is poor and both suffer problems from interference with reagent excess. 

Dimethyl yellow, see p-Dimethylaminoazobenzene Dimethyl yellow analar, see p-Dimethylaminoazobenzene Dimethyl yellow A.A-dimethylaniline, see p-Dimethyl-aminoazobenzene... 

Reductive cleavage of 4-dimethyl-aminoazobenzene by rat liver tissue. Intracellular distribution of the enzyme system and its requirement for triphosphopyridine nucleotide. Journal of Biological Chemistry, 180, 1125-1136. 

As with many enzymes the role of AMP aminohydrolase in the hierarchy of metabolic catalysts is not clearly understood. Enzymic activity in muscle is markedly reduced in the dystrophic mouse (161, 162), in humans suffering from Duchanne type muscular dystrophy (163), in hypokaliemic periodic paralysis (164), and upon denervation of normal and dystrophic mouse gastronemii (165). Activity is reported to increase in both transplanted and primary hepatomas (151) and in precancerous livers prior to the onset of neoplasia induced by feeding or by intraabdominal injections of the potent carcinogen 3 -methyl-4-dimethyl-aminoazobenzene (166). The weak carcinogen, 4 -methyl-4-dimethyl-aminoazobenzene was not effective (166). Increases in enzyme activity concomitant with altered nuclear-nucleolar morphology, nuclear RNA content, and nuclear RNA biosynthesis were also observed after injections of thioacetamide, a hepatocarcinogen (167, 168). 

Dabsyl Chloride (4-dimethyl-aminoazobenzene-4-sulfonyl chloride) Aabs = 420 nm. Derivatives are very stable (days) and can be formed from both primary and secondary amino acids. Detection is by absorption only. Detection limits are in the high picomole range. Reaction time is typically around 10 minutes at 70°C. Completeness of reaction can be adversely affected by the presence of high levels of various salts. Because reaction efficiency is highly matrix dependent and variable for different amino acids, standard amino acid solution should be derivatized under similar conditions/matrix for accurate calibration. Commercial systems available uti-... 

Although the activation energies of aminoazobenzene-type compounds (Ea between 75 and 88 kj moH) are not very different from those of azobenzene-type molecules, therm Z -> E isomerization of aminoazobenzene-type molecules is in general much faster than that of the azobenzene-type compounds. Conventional flash experiments are necessary to monitor the changes. The half-life of the Z-form of dimethyl-aminoazobenzene in toluene at 298 K is 220 s. A Linear Free Energy Rehitionship and Hammett relation is established, which includes azobenzene- and aminoazobenzene type compounds.A linear In vs, n, the Taft parameter of solvent polarity, is also observed. The dependence of the isomerization rate on pressure is weak In most solvents, it increases less than 35% at 2100 bar, AV -1.65 ml moLL Methanol is exceptional, with AV = -17 ml... 

The method of variation of the irradiation intensity gives as well as Po " 4-dimethyl-aminoazobenzene in n-hexane irradiation at 366 nm or 405 nm, both of which are wavelengths of the 7i —> 7U band, the results are 0F.- z = 0.17 and (j)2 i = 0.25. Albini et al.,"" who calculated the extent of Z —> E isomerization by an extrapolation of this conversion back to zero time of irradiation, found somewhat higher values for 4-diethylamino-... 

Dimethoxybenzindine Dimethyl aminoazobenzene 3,3 -Dimethyl benzidine Dimethyl carbamoyl chloride Dimethyl formamide... 

Analogous observation have been reported for the adsorption of basic indicators on some acidic adsorbents (64, 65). For example, p-dimethyl-aminoazobenzene, MegN—Ph— N=N—Ph (Me stands for CHg), is strongly adsorbed on silica-alumina, known to possess considerable proton acidity, with a color change from yellow to red. For a methanolic solution the spectral change is from an absorption band at 400 to one... 

Dimethoxybenzidine [119-90-4] Dimethyl aminoazobenzene [60-11-7] 3,3 -Dimethyl benzidine [119-93-7] Dimethyl carbamoyl chloride [79-44-7] Dimethyl formamide [68-12-2]... 

Two-dimensional TLC separations of 4-A/A -dimethyl-aminoazobenzene 4 -isothiocyanate protein derivatives were performed on polyamide using an acetic acid-water (1 2, v/v)... 

Figure 33 Solubilization (increase in absorbance) of dimethyl-aminoazobenzene by ovalbumin-SDS complexes in pH 7.4 (0.033 ionic strength) phosphate buffers at 25°C. (From Ref. 137.)...

J. Y. Chang, D. Brauer and B. Wittman-Liebold, Micro-Sequence Analysis of Peptids and Proteins using 4-NN-dimethyl-aminoazobenzene 4 -isothiocyanate/phenylisothiocyanate Double Coupling Method, FEBS Letters, 93 205-214 (1983). 

The behavior of G-6-Pase activity has also been examined during carcinogenesis and in the resulting primary tumors (Weber and Cantero, 1955a). Precancerous livers were taken from male Wistar rats of 200 gm., which were fed up to 150 days a semisynthetic diet in which 4-dimethyl-aminoazobenzene (DAB) was incorporated at a concentration of 0.06%. Control animals received the semisynthetic diet alone. Rats were sacrificed at different intervals after they had been on the diets for 50-60 days. Primary induced liver tumors were obtained from rats fed the DAB diet... 

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