Indo oranges

For health safety reasons, the lead based chrome yellows and oranges have been replaced by the much more expensive flavanthrone yellows, perinone and indo oranges. 

Fig. 7 Structures of the dyes forming aggregates on DNA (a) l-methyI-4-[[3-methyl-2(3//)-benzothiazolylidene]methyl]-quinolinium (Thiazole Orange, TO), (b) 3,3 -diethyIthiadicarbo-cyanine (DiSC2(5)), (c) 3,3 -trimethylammoniopropylthiadicarbocyanine (DiSC3+(5)), (d) 2- [(Z)-2-(2,5-dihydro-2-thienyl)-3 - [3 -methyl-2(3/f)-benzothiazolylidene] -1 -propenyl] -3 -methyl -benzothiazol-3-ium (L-21), (e) 2-[( )-3-[3,7-diethyT6-[( ,2 )-3-(l-ethyl-3,3-dimethyl-3/7-indo-lium-2-yl)-2-propenylidene]-6,7-dihydrothiazolo[5,4-/]benzothiazol-2(3//)-ylidene]-l-propenyl]-l-ethyl-3,3-dimethyl-3//-indolium (BCD), (f) 3-methyl-2-[( )-3-methyl-2-[[3-methyl-2(3/f)-ben-zothiazolylidene]methyl]-l-butenyl]-benzothiazol-3-ium (Cyan ]3iPr)...

Substrate products can be classified as either soluble or precipitating. Soluble peroxidase substrates include o-phenylenediamine, which is converted into a yellow product 2,2 -azino-(3-ethyl)-benzothiazoline-sulfonic acid, which is converted into a green product and tetramethylbenzidine, which is converted into a blue product. Precipitating substrates for peroxidase include 4-chloronaphthol, which yields a blue precipitate and aminoethylcarbizole, which forms a red precipitate. Alkaline phosphatase is most frequently used with p-nitrophenyl phosphate to give a yellow-orange soluble product, or with 5-bromo-4-chloro-3-indo-lyl-phosphate p-toluidine salt to yield an insoluble blue product. 

Uses Dye for wool, textiles leather limited use as shading component in soaps and wood stains colorant in hair dyes Manuf./Distrib. Aakash Chems. Dyestuffs http //members.aol.com/aakashchem/informati on.htmf, Anar Int l. http //www.anarchem.com-, Indo Colchem http //www.indocoi.com Acid orange 6... 

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