Diazobenzene sulfonate

Only few applications have been reported to determine antioxidants in rubbers or polymers by using electrochemical methods [927,928]. Sawada et al. [929] reported successful separations by coupling the antioxidants with p-diazobenzene sulfonic acid before electrophoresis. Amine AOs were coupled in acetic acid and phenolic AOs in NaOH-ethanol were analysed by CE methods. MEKC separation of the four major food grade antioxidants (PG, BHA, BHT, TBHQ) was completed within 6 min with pmole amount detection using UV absorption [930]. RPLC was not as efficient and required larger sample amounts and longer separation times. 

The inference that the oxidase(s) is an ectoenzyme has been made from a variety of data. The demonstration that PMNs possess both the Cu/Zn and the Mn superoxide dismutase prompted the suggestion that O must be formed at a site which protected it from the action of these enzymes. Since O appeared in the fluid surrounding the PMN, the most advantageous site appeared to be the plasma membrane. In accord with this proposal, treatment of PMNs with a nonpenetrating organic anion, p-diazobenzene sulfonic acid, in association with cytochalasin B to prevent internalization of membrane into a phagocytic vacuole, inhibited the... 

Dr Walter stated also that diazobenzene-sulfonic acid(prepd by diazotization of sul-fanilic acid) readily couples with aromatic -NHj in acid medium or with -OH group in alkaline medium, provided at least one ortho-or para- standing H-atom is available. The reaction proceeds as follows ... 

Diazobenzene sulfonic acid see Benzenediazonium sulfonic acid 2 B57... 

Benzenediazonium Sulfanic Acid(Diazobenzene Sulfonic Acid), N2.C6H4.02.S mw 184.17,... 

Desensitization of the enzyme to AMP inhibition can also be accomplished by treatment with diazobenzene sulfonic acid (41)- In this case loss of AMP sensitivity is observed when approximately 4 monoazotyrosine residues are formed. 

Fluorescence arises from aromatic by-products which, however, can be entirely separated by careful work. Pure ac-tetrahydro-/5-naphthylamine gives no color with diazobenzene sulfonic acid. 

The polaragraphic analysis of NMe was studied in buffered solns. The half wave potential was found to vary with pH hence the necessity of using a buffered scln (Ref 22). Gas CjirGiTiatGg retention times for NMe at 50-90° and 110— 50° are listed in Ref 38, various supports and stationary phases were used. Small amts were quanty detd by coupling with p-diazobenzene-sulfonic acid and detg the colored prod spec-trophotometrically (Ref 37)... 

Diazobenzene Sulfonic Acid. See Benzenediazonium Sulfonic Acid in Vol 2, p B57-L... 

The oxidation (KMnOi) of strychnine to iV-oxalylanthranilic acid (114) suggests the direct attachment of a nitrogen atom to a benzene nucleus. This is the Na atom because dimethylstrychnine exhibits the properties of an A -disubstituted aniline with a free poro-position, where it couples with benzaldehyde (zinc chloride) to give a leuco base or with diazobenzene-sulfonic acid to give a colored azo compound (2). 

Davis and co-workers [25] separated antioxidants on Whatman NOAC 82 acetylated paper using ethanol - benzene - acetylacetone (10 10 1) as mobile phase and potassium-p-diazobenzene sulfonate as detection reagent. Korn and Waggon [26] separated urea based stabilisers on paper using propanol - methanol - water (2 1 1) migration and p-dimethyl-benzaldehyde detection. 

Johnson and Jones, Am. Chem. J., 40, 538 (1908), noted the production of a red color from the action of diazobenzene-/>-sulfonic acid on isobarbituric acid in the presence of sodium bicarbonate. They neither isolated the product nor proposed a structure for it, but related it to the colors obtained by Johnson and Clapp, J. Biol. Chem., 5, 163 (1908), by the action of diazobenzene-/>-sulfonic acid on all uracil derivatives in which the 1-position was unsubstituted. [In Johnson s papers this position is munbered 3. The numbering in the present paper conforms with the system adopted by Chemical Abstracts.]... 

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