Methylene violet

The stmcture of indophenol-type sulfur dyes was studied (21) on Cl Sulfur Blue 9 made from the indophenol (13). This compound was purified and brominated to a tetrabromo derivative (14) identical with that obtained on hromin ation of Methylene Violet [2516-05-4] (15). 

Thus, the presence of a thiamine ring in Cl Sulfur Blue 9 was conclusively proved. The thiamine ring is the fundamental chromophore that accounts for the high color value of both the sulfur dye and Methylene Blue [61-73-4] including their abiUty to form pale yeUow leuco forms on reduction. Methylene Violet (15) is obtained from Methylene Blue (16) by hydrolysis in boiling alkah. 

There are cationic thiazine dyes (3 to 5) and neutral thiazinone dyes exemplified by Methylene Violet (6). Like leuco Methylene Blue, leuco Methylene Violet is too air sensitive to be isolated and therefore requires acylation. 

The leucos lla-d are claimed to give blue gray images in electrolytic recording instead of the purple color of Methylene Violet from which they are derived.7... 

Compound 12 can be described as a true leuco Methylene Violet since a purple image is obtained on oxidation with a metal nitrate.Sa... 

Methylene Violet, which is a well-known phenothiazinone dye, is also reduced and acylated in one step by refluxing with zinc powder in an acid anhydride. 

Reduction of Methylene Violet with zinc in acetic acid gives the air-sensitive leuco 20 which is further reacted with acetic anhydride in mild conditions to yield the acetylated leuco 21. The latter being air stable can be isolated and, the ring N-H being less reactive is not affected by acetylation at room temperature. The leuco 21 is again aroylated to produce the leuco 22. Selective hydrolysis provides the desired leuco dye 12 which regenerates the true Methylene Violet (6) on oxidation.83... 

Derivatives of Methylene Violet 6 possessing long aliphatic chains are obtained by oxidative coupling of 3-acetoxyphenothiazine with a secondary amine in the presence of an oxidant such as iodine. The oxidative coupling of phenothiazine with amine is well known but in this case the reaction does not stop there but proceeds further at reflux temperatures to the phenothiazinone 74.9 Reduction of the latter dye and treatment with acetic anhydride yields the ballasted phenothiazine 6. Reaction of 75 with the dye chloroformate 70 yields the ballasted leuco dye developer 76. 

Paraphenylene violet, rhoduline violet, rhoduline heliotrope, methylene violet, methylene hehotrope, tannin heliotrope, ins violet, amethyst violet, cresyl fast violet fit < > 0 ... 

Sastry et al. [25] also described a fairly sensitive spectrophotometric method for the determination of mefenamic acid based on the formation of a chloroform-soluble, colored ion-association complex between mefenamic acid and methylene violet at pH 7.6. The absorbance of the... 

By the sodium mirror technique, Bruin et obtained in dioxan anion radicals from 3,7-diaminophenothiazine (Lauth s violet), from 3,7-bis-dimethylaminophenothiazine (methylene blue), from 7-di-methylaminophenothiazone (methylene violet), and from phenothiazine itself. From the very well resolved ESR spectra of these radicals the value x 7 G was derived. 

The dimethyl derivative of thionoline (Methylene Violet) is formed by boiling methylene blue with alkali, methylene azure, the sulphone of methylene blue, CigHiyNgSOj, being simultaneously produced [36]. 

Magenl 6, 593 Malachite Green, 368 Mauveine, 370 Meldola Blue, 369 Merantine Blue, 379 Methyl Green, 368, 369 Methyl Violet, 7 Methylene Blue, 369, 379 Methylene Violet, 370... 

Skripchenko A, Robinette D, Wagner JS. Comparison of methylene blue and methylene violet for photoinactivation of intracellular and extracellular virus in red suspensions. Photochem Photobiol. 1997 65 451-5. 

The average viability (determined by methylene violet or methylene blue staining) of dried yeast is 20-30% lower than that of freshly propagated yeast. This problem can be accommodated by pitching according to viable cell numbers. 

Six dyes as new visualizing reagents gentian violet, methylene violet, methylene blue, methyl green, malachite green, and Janus blue, have been used to detect ( )-a-... 

Fig. 2 Densitograms of 25.00 p,g ( )-a-tocopherol after detection with (a) Rhodamine B (b) methylene violet.

Other Names C.I. 52041 Dimethylthionoline Methylene Violet Methylene Violet (biological stain) Methylene Violet Bernthsen NSC 187694 Merck Index Number Not listed Chemicai/Dye Class Phenothiazine... 

Tzung, C. Methylene Violet (Bernthsen), by zinc-alkali-chlorate hydrolysis of methylene blue. Stain Technol. 1964, 39, 351-358. 

Dutt, M. K. In situ absorption spectra of PAS and feulgen-positive substances stained with methylene violet. Indian J. Exp. Biol. 1978,16, 253-254. 

Smart, K. A. Chambers, K. M. Lambert, I. Jenkins, C. Use of methylene violet staining procedures to determine yeast viability and vitality. J. Am. Soc. Brewing Chem. 1999, 57, 18-23. 

Eosin B 171 2516-05-4 Methylene Violet (Methylene Violet Bernthsen) 298... 

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