from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. 1,2,7-trihydroxyanthraquinone
from The Century Dictionary and Cyclopedia
- n. A mordant color, a trihydroxyanthraquinone, C6H3OH(CO)2C6H2(OH)2, isomeric with purpurin: sometimes called isopurpurin.
Sorry, no etymologies found.
"Alizarins for reds" all contain more or less of alizarin properly so-called, from 1 to 10 per cent., along with anthrapurpurin and flavopurpurin.
It is now known, thanks to the researches of Perkin, Schunck, Roemer, Graebe, and Liebermann, that in the manufacture of artificial alizarin there are produced three distinct coloring matters -- alizarin, iso or anthrapurpurin, and flavopurpurin, the two latter being isomers of purpurin.
Anthrapurpurin and flavopurpurin are obtained from two isomeric disulphanthraquinonic acids, improperly named isoanthraflavic and anthraflavic acids, which are converted into anthrapurpurin and flavopurpurin by a more profound action of potassa.