Anthraflavic acid

Anthraquinones, coumarins, flavonoids, and terpenoids alizarin, anthraflavic acid, bomeol, chrysin, emodin, eugenol, 4-ethylphenol, galangin, 7-hydroxy flavone, menthol (low), 4-methylumbelliferone (low), 1-naphthol, naringen (low),... 

Anthraflavic acid (= 2,6- Synthetic anthraquinone cf. Emodin MLCK (37), PKA (60),... 

Flavopurpurin is obtained from a-anthraquinonedisulphonic acid anthraflavic acid, an isomer of alizarin, is formed as a bye-... 

On alumina mordants it gives a red, which is still yellower than that with isopurpurin. Its principal application is in printing, while that of isopurpurin is in dyeing. Anthraflavic acid and isoanthraflavic acid sometimes occur in the commercial products. They are entirely valueless in dyeing, and are produced in badly conducted operations. 

Beilstein Handbook Reference) 9,10-Anthracenedione, 2,6-dihydroxy- Anthraflavic acid Anthraflavin Anthraquinone, 2,6-dihydroxy- BRN 2054127 CCRIS 5593 EINECS 201-544-3 NSC-33531. Used as a basis for pigments and dyestuffs. Solid mp > 320 . 

Alizarin, anthraflavic acid, apigenin, Benzo(a)pyrene-t-7,... 

Alizarin, anthraflavic acid, apigenin, Benzo(<3)pyrene-t-7, 8-dihydrodiol IR- and 85-glucuronides), emodin, fisetin, flavoperidol, genistein, naringenin, quercetin, quinalizarin, 4-methylumbelliferone, scopoletin, carvacrol, eugenol, 1-naphthol, p-nitrophenol, 4-aminobiphenyl,... 

Anthraflavic and isoanthraflavic acids are detected by treating a little of the substance suspended in boiling water with barium hydroxide and filtering the liquid in presence of the above acid the filtrate is red and gives a yellow precipitate when neutralised with hydrochloric acid. 

The filtrate is treated with hydrochloric acid and the precipitate obtained boiled with milk of lime, which dissolves the anthraflavic and isoanthraflavic acids with red coloration. The solution is filtered and the filtrate precipitated with hydrochloric acid, the precipitated anthraflavic and isoanthraflavic acids being filtered off, washed, dried and weighed. 

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