Disodium-3-hydroxy-naphthalene-2,7-disulfonate

A method frequently used to determine aromatic amines in water-soluble dyes involves their extraction with chloroform, followed by diazotization of amines and coupling of diazonium salts with a reagent R-salt (disodium-3-hydroxy-naphthalene-2,7-disulfonate) or pyrazolone T (4,5-dihydro-5-oxo-l-(4-sulfophenyl-)l/7-pyrazole-3-carboxylic acid). The separated products are detected by UV-VIS spectrophotometry or fluorescence (210-212). 

The Chemicaly3.bstractIndexis 2,7-naphthalene-disulfonic acid, 4-amino-5-hydroxy-3-[[4 -[(4-hydroxyphenyl)azo] [l,l -biphenyl]-4-yl]azo]-6-(phenylazo)-, disodium salt. 

SYNS A.F. RED No. 1 CERVEN KUMIDINOVA C.1.16155 C.I. FOOD RED 6 C.I. FOOD RED 6, DISODIUxM SALT DISODIUM-3-HYDROXY-4-((2,4,5-TRIMETHYLPHENYL)AZO)-2,7-NAPHTHALENE-DISULFONATE DISODIUM-3-HYDROXY-4-((2,4,5-TRIMETHYLPHENYL)AZO)-2,7-NAPHTHALENE-DISULFONIC ACID DISODIUM-3-HYDROXY-4-((2,4,5-TRIMETHYLPHENYL)AZO)-2,7-NAPHTHALENE-DISULPHONATE DISODIUM-3-HYDROXY-4-((2,4,5-TRIMETHYLPHENYL)AZO)-2,7-NAPHTHALENE-DISULPHONIC ACID DOLKWAL PONCEAU 3R EXT. D C RED No. 15 3-HYDROXY-4-((2,4,5-TRIMETHYLPHENYL)AZO)-2,7-NAPHTHALENE-DISULFONIC ACID, DISODIUM SALT 3-HYDROXY-4-((2,4,5-TRIMETHYLPHENYL)AZO)-2.7-NAPHTHAL-ENEDISULPHONIC ACID, DISODIUM SALT MAPLE PONCEAU 3R PONCEAU 3R SODIUM CUMENE-AZO-P-NAPHTHOLDISULPHONATE USACERTRED No. 1... 

Disodium 5-amino-4-hydroxy-3-(phenylazo) naphthalene-2,7-disulfonate Fast acid magenta 2,7-Naphthalenedisulfonic acid, 4-amino-5-hydroxy-6-phenylazo-, disodium salt Naphthalene red B Red no. 227 Classification Monoazo color Empirical C16H13N3O7S2 2Na Properties M.w. 469.42 Toxicology Mutagen TSCA listed... 

In our laboratory, this method was appUed to the purification of food mono-azo dyes. Amaranth, New Coccine, and Sunset Yellow FCF were purified at 99.7%, 99.5%, and 99.3%, respectively, from 1-23 g of commercial dyes. Continued research has led to the purification of impurities present in commercial Sunset Yellow FCF that include RS-SA (trisodium salt of 3-hydroxy-4-[sulfophenyl] azo-2,7-naphthalene disulfonic acid), GS-S A (1 -[4-sulfophenyl]azo)-2-naphthol-6,8-disulfonic acid), DONS (disodium salt of 6,6 -oxybis-2-naphthalene sulfonic acid), and 2N-SA (sodium salt of 4-[(2-hydroxy-l-naphthalenyl)azo]benzenesulfonic add). The method successfully isolated GS-SA from Sunset Yellow FCF. " ... 

CAS 6441-93-6 EINECS/ELINCS 229-231-7 Synonyms 5-(Acetylamino)-4-hydroxy-3-[(2-methylphenyl) azo]-2,7-naphthalenedisulfonic acid, disodium salt Cl 18065 Disodium 5-(acetylamino)-4-hydroxy-3-[(o- tolyl) azo] naphthalene-2,7-disulfonate 2,7-Naphthalenedisulfonic acid, 5-(acetylamino)-4-hydroxy-3-[(2-methylphenyl) azo]-, disodium salt... 

CAS 5413-75-2 EINECS/ELINCS 226-502-1 Synonyms Acid red 73, disodium salt Cl 27290 7-Hydroxy-8-[[4-(phenylazo) phenyl] azo]-1,3-naphthalenedisulfonic acid, disodium salt 7-Hydroxy-8-(4-phenylazophenylazo) naphthalene-1,3-disulfonic acid, sodium salt 1,3-Naphthalenedisulfonic acid, 7-hydroxy-8-((4-(phenylazo) phenyl) azo)-, disodium salt Classification Azobenzene diazo color Empirical C22HieN4Na207S2 Properties M.w. 558.48 Uses Dye for wool, silk, polyamide, resins, stains, and soaps colorant in hair dyes Manuf/Distrib. ABCR http //www.abcr.de] Aldrich http //www.sigma-aldrich.com] Anar Infl. http //www.anarchem.com] Dudley http //www.dudiey-chem.com] Fluka http //www.sigma-aldrich.com Acid red 87... 

CAS 3567-66-6 EINECS/ELINCS 222-656-9 Synonyms Acid red 33 5-Amino-4-hydroxy-3-(phenylazo)-2,7-naphthalenedisulfonic acid disodium salt Azo fuchsine D C Red No. 33 Disodium 5-amino-4-hydroxy-3-(phenylazo) naphthalene-2,7-disulfonate Food red 12 2,7-Naphthalenedisulfonic acid, 4-amino-5-hydroxy-6-phenylazo-, disodium salt Red 33, disodium salt Classification Monoazo color Empirical Ci6Hi3N3Na207S2 Formula C16H13N3O7S2 2Na Properties M.w. 469.42 Toxicology Mutagenic data TSCA listed Hazardous Decomp. Prods. Heated to decomp., emits toxic vapors of NOx and SOx Uses Colorant in cosmetics, pharmaceuticals See also Acid red 33 D C Red No. 33... 

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