Blue violet dyes

Pyrazolinones belong to the heterocyclic class of coupler and are widely used the sulfonamide (124) is representative of this type (51USP2537098). Substituted thiophenes (125) (58GEP1025265) and hydroxypyridones (126) (47USP2431190) are couplers which form blue-violet dyes resistant to light. Pyranones (127), analogous to the latter, have also been used (51USP2542849). 

This type of dye coupler reacts with dye precursors to give blue-violet dyes that have been shown to be 2-aminoindamines [34]. Mechanistically, the formation of 2-aminoindamines is related to the formation of indophenols and fits the general scheme described earlier. 

Amino add raagants reagents for the colorimetric identification and quantitation of amino acids. One of the most important is ninhydrin (2,2-dihy-droxy-lH-indene-13(2H)-dione), which reacts with amino acids to form a blue-violet dye called Ruhe-mann s purple (absorbance maximum 570 nm). With the imino acid, proline, ninhydrin forms a yellow product, absorbance maximum 440 nm. 

Immunologic An allergic reaction, with urticaria, edema of the eyelids and lips, and hypotension, occurred after the use of Patent Blue Violet dye for lymphangiography [56 ]. 

Dyes. Vital dyes have been used for many years in a variety of clinical situations. Patent blue V (also called E131, Acid blue 3, Disulfine blue) and Isosulfan blue (also called Patent blue violet or Lymphazurine), belong to the group of triarylmethane dyes and are the most commonly used [24]. Reports of IgE-dependent anaphylaxis arise. Anaphylactic reactions involving methylene blue seems to be very rare, however, several reports of sensitization to both Patent blue and methylene blue have previously been reported. 

Direct and derivative spectrophotometric and IP-RP-HPLC methods were applied to identify and determine synthetic dyes and follow their degradation processes. " The dyes considered were Tartrazine (E 102), Quinoline Yellow (E 104), Sunset Yellow (E 110), Carmosine (E 122), Amaranth (E 123), New Coccine (E 124), Patent Blue Violet (E 131), and Brillant Blue ECE (E 133). All are considered representative additives for soft drinks. 

Chohnesterase-inhibiting pesticides (e g., organophosphate and carbamate pesticides) are detected by dipping the developed chromatogram in a solution of the enzyme chohnesterase followed by incubation for a short period. Then the plate is dipped in a substrate solution, e.g., 1-naphthyl acetate/fast blue salt B. In the presence of the active enzyme, 1-naphthyl acetate is hydrolyzed to 1-naphthol and acetic acid, and the 1-naphthol is coupled with fast blue salt B to form a violet-blue azo dye. The enzyme is inhibited by the pesticide zones, so the enzyme-substrate reaction does not occur pesticides are, therefore, detected as colorless zones on a violet-blue background [36]. 

Figure 7.7. Numerically, azo dyes form by far the most important chemical class of disperse dyes. Azo disperse dyes may be classified into four broad groupings. The most numerous are the aminoazobenzenes which provide important orange, red, violet and blue disperse dyes. They are exemplified by C. I. Disperse Orange 25 (157), C. I. Disperse Red 90 (158) and C. I. Disperse Blue 165 (159). A comparison of these three aminoazobenzene dyes provides an illustration of the bathochromic shift...

All dyes absorb light. Fluorescent dyes re-emit the absorbed energy as light of longer wavelengths. An FBA is a fluorescent chemical that absorbs in the ultraviolet region of the spectrum and emits blue-violet light. A typical FBA shows maximum absorption at a... 

Monoarylation of l-amino-4-hydroxyanthraquinone (6.39 X = OH) results in violet dyes such as Cl Disperse Violet 27 (6.44 R = H) and the bluish violet Cl Disperse Blue 72 (6.44 R = CH3) the latter dye is also important as Cl Solvent Violet 13. Chlorination of 1,4-diaminoanthraquinone with sulphuryl chloride gives the 2,3-dichloro derivative (Cl Disperse Violet 28), which on condensation with phenol yields Cl Disperse Violet 26 (6.45). Monoaryl or dialkyl derivatives of 1,4-diaminoanthraquinone (6.19 Cl Disperse Violet 1) are blue. Typical examples include Cl Disperse Blue 19 (6.46) and Cl Disperse Blue 23 (6.47). 

In 1904 Bally obtained a bluish violet solid by alkali fusion of benzanthrone at approximately 220 °C. Two isomeric compounds were isolated by vatting the reaction mixture and filtering off a sparingly soluble sodium salt. Oxidation of the filtrate gave a blue vat dye, violanthrone (6.75 Cl Vat Blue 20), as the main component. The less soluble residue similarly afforded a violet product, isoviolanthrone (6.76 Cl Vat Violet 10). The formation of isoviolanthrone can be suppressed by carrying out the fusion in a solvent such as naphthalene or a polyethylene glycol in the presence of sodium acetate and sodium nitrite. Dyes of this type are often referred to as dibenzanthrones. 

The dioxazine ring system is the source of some valuable violet pigments, such as Cl Pigment Violet 23 (6.211). This colorant is obtained by condensing 3-amino-9 ethylcarbazole with chloranil. Sulphonation of the pigment gives the dye Cl Direct Blue 108. Triphenodioxazines have recently been the source of some blue reactive dyes [241-Examples are known of symmetrical bifunctional structures (6.212 NHRNH = alkylenediamine, Z = haloheterocyclic system) and unsymmetrical monofunctional types such as 6.213 [37]. 

Aqueous or methanolic ferric chloride is a general spray reagent for phenolic compounds and gives a blue-black coloration with flavonoids. Similarly, Fast Blue Salt B forms blue or blue-violet azo dyes. 

Janus Green B (3-dimethylamino-7-[4-dimethylaminoazo]-5-phenylphenazonium chloride (2869-83] M 511.1. Dissolves in H2O to give a bluish violet soln which becomes colourless when made lOM in. NaOH. Dissolve in EtOH to give a blue-violet colour, filter from insoluble material then add dry Et2O whereby the dye separates out leaving a small amount of blue colour in soln. Filter off the solid and dry in vacuum. Store in a dark bottle. 

Derived from tribenzodioxazine (79), coloured compounds of this type have been known since 1928 and have been used as reddish-blue direct dyes for cotton. An important violet, Carbazole Dioxazine Violet (80), was prepared by condensation of 3-amino-A-ethylcar-bazole with chloranil followed by cyclization of the intermediate diimine and pigmentary conditioning (56GEP946560). A second useful synthesis involves condensation of an o-alkoxyarylamine with chloranil followed by cyclization (65C242). 

Anthracene is obtained from coal lai in the fraction distilling between 300° and 400°C. This fraction contains 5-10% anthracene, from which, by fractional crystallization followed by crystallization from solvents, such as oleic acid, and washing with such solvents as pyridine, relatively pure anthracene is obtained. It may be detected by the formation of a blue-violet coloration on fusion with mellitic add. Anthracene derivatives, espedally anthraquinone, are important in dye chemistry. 

Such anionic surfactants that form ion pairs with methylene blue and that are extractable with chloroform are known as Methylene Blue Active Substances (MBAS). Other cationic dyes, such as crystal violet dye, may be used instead of methylene blue. Extraction of such an ion-pair complex into benzene has been reported (Hach, 1989). Detection Limit = 10 pg/L. 

A redder and brighter shade is obtained with isoviolanthrone. Its halogenation products are marketed as brilliant violet dyes. Related to violanthrone is the alkaline ring-closure product of 3-pyrazolanthronylbenzanthrone, which is used as a navy blue vat dye. 

Violet and blue hydrazone dyes are obtained with a methylene base derived from naphtholactam (13) [33],... 

Through the choice of suitably substituted diazo components, bluish red to blue wool dyes with good light- and wetfastnesses can be produced, e.g., C.I. Acid Violet 14, 17080 (7) [4404-39-1],... 

The cationic groups can also be introduced by other methods such as chloro-methylation and quatemization [13] or be converted by curing suitable hydroxymethyl compounds [14] with a pigment. In this way, for example, the lightfast cationic blue paper dye 28 can be obtained with C.I. Pigment Violet 23 51319 [6358-30-1]. 

Nitro dyes are the most important class of direct hair dyes they are substituted derivatives of nitrobenzene or nitrodiphenylamine [3, Nitro and Nitroso Dyes]. By proper selection of donor groups and substitution site on the benzene ring, a spectrum of dyes from yellow to blue violet can be prepared [9, pp. 247-250], [40] (Scheme 3). 

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