Quinoline dyes

Likewise, quantum mechanical calculation succeeds in giving a theoretical explanation of some facts that the resonance theory could not explain, for example, why bis(pyridine-2)monomethine cyanine and bis(pyridine-4)monomethine cyanine possess the same lowest energy transition contrary to the 2,2 - and 2,4 -quinoline monomethine dyes, together with a molecular coefficient extinction lower than that of the 4,4 -quinoline dye (11). Calculation shows also that there is no theoretical reason for observing a relationship between and pK in a large series of dyes with different nuclei as it has been postulated, even if limited observations and calculations in short homogeneous series could lead to this conclusion (105). 

Quinoline Dyes. The reaction of 2-methylquinoline with phthahc anhydride produces a 2 1 mixture of 2-(2-quinolinyl)-l,3-indandione... 

This mixture is known as Quinoline Yellow A [8003-22-3] (Cl 47000) and is most widely used with polyester fibers (109). Upon sulfonation, the water-soluble Quinoline Yellow S or Acid Yellow 3 [8004-92-0] (Cl 47005) is obtained. This dye is used with wool and its aluminum salt as a pigment. Foron Yellow SE-3GL (Cl Disperse Yellow 64) is the 3-hydroxy-4-bromo derivative. Several other quinoline dyes are commercially available and find apphcations as biological stains and analytical reagents (110). 

Quinoid-type chromophoric structures, reactions of, 21 36-37 Quinoline (QI), 12 723, 725-726 soluble dyes, 7 373t Quinoline-4-carboxylic acids, 21 190 Quinoline derivatives, 21 196-214 Quinoline-derived drugs, 21 197-198t Quinoline dyes, 21 196 Quinoline, formation of, 21 109. See also Quinolines... 

Quinoline Dyes. The reaction of 2-inelhylquinoline with phlhalic anhydride produces a 2 1 mixture of 2-(2-quinolinyl)-1,3-indandione ((5), R—H 1 and 2-(6-methyl-2-quinolinyi)-1.3-indandione ((5), R — CH3). 

This mixture is known as Quinoline Yellow A and is most widely used with polyester fibers. Several other quinoline dyes are commercially available and find applications as pigments, biological stains, and analytical reagents. 

Baughman (1992) measured the disappearance rate constants for a number of solvent and disperse azo, anthraquinone, and quinoline dyes in anaerobic sediments. The half-lives ranged from 0.1 to 140 days. Product studies of the azo dyes showed that reduction of the azo linkages and nitro groups resulted in the formation of substituted anilines. The 1,4-diaminoanthraquinone dyes underwent complex reactions thought to involve reduction and replacement of amino with hydroxy groups. Demethylation of methoxyanthraquinone dyes and reduction of anthraquinone dyes to anthrones also was observed. 

Unsymmetrical benzothiazole-quinoline dye 10, benzothiazole-benzoxazole dye 11, and benzimidazole-benzoxazole dye 12 are also effective green sensitizers. It is important that these dyes J-aggregate and absorb between 500 and 600 nm with a peak absorbance at ca. 550 nm. 

In the presence of electroosmotic flow, opposite charged dyes can be separated at particularly high separation speed on a time scale of 100 ms generating up to 18,600 theoretical plates/second, as reported by Jacobson et al. [63 ]. The same group has reported rapid separations of metal ions (Zn2+, Cd2+, Al3+) complexed with a fluorescent quinoline dye on a quartz microchip [32]. Channel walls were coated with polyacrylamide to prevent electroosmotic flow, the separation was achieved in less than 20 s at 870 V/cm and L = 16.5 mm. 

The method is based on the transformation of kynurenic acid into a substance of the type of the quinolinic dyes of Besthorn, but more stable toward light. 

This is not D C yellow 10. Although the C.I. numbers are the same, the dyes differ in composition. Quinoline yellow is primarily the disulfonated quinoline dye, whereas D C yellow 10 is the monosulfonated color. Quinoline yellow is not accepted for use in the U.S. conversely, D C yellow 10 cannot be used in the EU. 

Pitch, product of coal tar distillation Pulp colors, organic Quinoline dyes Resorcinol Scarlet 2 R lake Stilbone dyes Styrene... 

In pharmacy, the dyes used are azo dyes, quinoline dyes, tri-phenylmethane and xanthine dyes. They are not recommended in children because many colouring agents, mainly synthetic dyes, have been associated with hypersensitivity and other adverse reactions (gastrointestinal intolerance, dermatological reactions and carcinogenic concerns). Approximately 2-20% of people with asthma are sensitive to aspirin. Cross-reactions to azo dyes such as tartrazine produce similar effects. They have occurred in patients both with and without a history... 

Polarized IR spectroscopy can also be successfully applied to quinoline dyes, such as the derivatives depicted in Figure 6.23. In these cases, crystallographic data are for the three known structures shown in Table 6.6. In these cases, the polarized IR spectroscopy in the solid state appeared to be especially attractive. 

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