Pigments indigoid

There are three color additives of the indigoid type, including D C Blue No. 6 (35) (an insoluble pigment), FD C Blue No. 2 (2) (the water-soluble disodium sulfonate derivative of indigo), and D C Red No. 30 (23) (an insoluble thioindigoid). AH are related to indigo [482-89-3] which has stmcture (35) (Fig. 3). 

M. Puchalska, K. Polec Pawlak, I. Zadrozna, H. Hryszko and M. Jarosz, Identification of indigoid dyes in natural organic pigments used in historical art objects by high performance liquid chromatography coupled to electrospray ionization mass spectrometry, J. Mass Spectrom., 39, 1441 1449 (2004). 

This chromogen (1.13) is somewhat reminiscent of the indigoid and anthraquinone types but it has not yielded useful vat dyes. Bluish red pigments of the quinacridone class are especially important in violet and magenta colours or for deep reds in admixture with inorganic cadmium scarlets. 

The foregoing considerations can also be applied to the electrochemistry of a number of organic compounds in contact with aqueous buffers [107, 119-125]. Here, protonation/deprotonation reactions are coupled with electron transfer processes, as described for the case of indigoid-, anthraquinonic-, and flavonoid-type pigments, among others. In contact with aqueous electrolytes, the electrochemical processes can generally be described as ... 

The synthetic food colorants, according to their chemical structure, belong to mono-, di-, and trisazo, triarylmethane, xanthene, quinoline, and indigoid. They can also be divided into water-soluble, oil-soluble, insoluble (pigment), and surface marking colors. 

Keywords Agriculture Animal health Cyanine dye Dietary supplements Diindolylmethane Essential oils Havoring Indigoid dye Indole-3-carbinol Melatonin Nutraceutical Perfume Pigments Textile dyes Tryptophan... 

Examples of tetrapyrroles include porphyrins and porphyrin derivatives and more specifically, chlorophylls, heme pigments and bilins. Examples of tetra-terpenoids or carotenoids include carotenes and xanthophylls. Examples of quinines include benzo-quinones, anthraquinones and naphthiquinones. Examples of oxygen-containing heterocyclic compounds such as flavonoids include anthocyanins and flavonols. Examples of nitrogen-containing heterocyclic compounds include indigoids and indole derivatives, such as betalaines and eumelanins, and substituted pyrimidines such as pterins and purines. 

Indigoid group Polycyclic pigments group Indigo... 

McClay K, Boss C, Keresztes I, Steffan RJ. 2005. Mutations of toluene-4-monooxygenase that alter regiospecificity of indole oxidation and lead to production of novel indigoid pigments. Appl Environ Microbiol 71 5476-5483. 

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