Alizarin Green

Phenoxazin-3-ones and phenothiazin-3-ones can be prepared by condensation of 2-aminophenols or -thiols with quinones. Alizarin Green G (61), for example, is obtained from (59) and (60). Similarly, 2-aminothiophenols and 6-chloro-2-methoxy-l,4-benzoquinone (62) afford phenothiazin-3-ones (63). 

Alizarine cyanol E F, alizarine saphlral, alizarine direct cyanine, alizarine direct blue E B, E 3 B, anthraquinone blue, h anthracyanine, eriocyanine L M, fast sky blue, brilliant anthrazurol, alizarine emeraldol G, acid alizarine green G. M s. ... 

Alizarine red (S marks), Erweco alizarine acid red, alizarine orange S W, alizarine cyanine, brilliant alizarine cyanine, anthracene blue (S Marks), acid alizarine blue, alizarine dark green W, alizarine blue (S Marks), alizarine green A alizarine black S, alizarine indigo blue (S Marksl, coeruleine (S Marks). 0 n the addition of a few drops of dilute caustic soda (1 20), the colour becomes more 1 intense, and bluer ... 

Coeruleine, alizarine green S, alizarine dark green W. 

If the mixture be heated to 120°, or if alizarin blue-green is heated with concentrated sulphuric acid to 120°, an intramolecular change takes place, a new mono-oxyalizarin blue monosulphonic acid being formed. This body is an article of commerce, and is Icnown as Alizarin Green S. 

If, finally, the temperature of the reaction between sulphuric acid and alizarin blue be raised to 200° to 210°, or if alizarin green is heated to the same temperature with concentrated sulphuric acid, a third dyestuff. Alizarin Indigo-blue, is obtained. This body is a trioxyalizarin-blue. The commercial products are pastes which contain the bisulphite compounds. The shades produced in dyeing are sufficiently indicated by the names, being a dull indigo-blue and a dull bluish green respectively. The best results are obtained with chromium mordants. 

RR, Alizarin Green sulfur, Nigrosine 2Y, and Naphthalene Blue RS are used for this purpose. 

The antioxidant activity of alizarin was established in four different assays (1) suppression of light emission in the p-iodophenol enhanced chemiluminescent assay, (2) scavenging of superoxide anion (02 -) in a hypoxanthine-xanthine oxidase system, (3) protection of rat liver microsomes from lipid peroxidation by ADP/iron(II) ions, and (4) protection of bromobenzene-intoxicated mice from liver injury in vivo [141]. Alizarin was compared with Trolox (water soluble vitamin E), the flavonoid baicalin and green tea proanthocyanidins. In assay (1) the activity of alizarin was 76% of that of Trolox. In assay (2) the inhibition of 02 -induced chemiluminescence was 40%, 32%, 23% and 14% for Trolox, alizarin, green tea polyphenols and baicalin respectively. Alizarin was not significantly active in the lipid peroxidation assay but after baicalin the most active compound in the in vivo assay. This shows again the difficulty in the evaluation of antioxidant activity and the differences between in vitro and in vivo assays [141]. 

This reaction has been applied to the technical preparation of important dyes such as Alizarin Green S, Alizarin Bordeaux, Alizarin Cyanine R, and Alizarin Cyanin Black. ... 

The term alizarin appears to have been used historically for a wide range of colours not within the normal range of alizarin-metal complexes (such as Alizarin blue and Alizarin green ) these are probably instances of attempts to name pigments on the basis of a supposed chemical relationship or perhaps a colour or behavioural similarity only (Heaton, 1928). 

Carlyle (2001) foimd this listed in a Winsor Newton catalogue of 1900. However, the precise composition is unknown and it is probably one of the synthetic dye-based pigments to which the term alizarin (q.v.) was inaccurately applied historically. For example, Heaton (1928) lists Alizarine green (sic), stating that it was a derivative of alizarine . 

Strictly the name Alizarine green applies to the sodium salt. 

Alizarine fluorine blue, A-00076 Alizarine fluorine blue S, A-00077 Alizarine fluorine blue sulfonate, see A-00077 Alizarine green, A-00078... 

Acid chrome violet K Na salt, in A-00055 Alizarine green Na salt, in A-00078... 

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