Anthraquinones alizarin

Nitroalizarin (l,2-dihydroxy-3-nitro-9,10-anthraquinone. Alizarin Orange) [568-93-4] M 285.2, m 244" (dec), pKEst(i) 4.6, pKEst(2) 9.6. Crystd from acetic acid. 

Quinones that are based on the anthracene ring system are called anthraquinones. Alizarin is one example of an anthraquinone dye. 

ABSTRACT The roots of Rubia tinctorum L. (madder) are the source of a natural dye. In this review for the first time all the different information on Rubia tinctorum available in the literature is summarised. The dye components are anthraquinones which probably contribute to the resistance of the plant against fungi in the soil. Madder roots have been used to dye textiles in many parts of the world since ancient times and an overview of the historical development, cultivation, harvesting and dyeing techniques of madder is given. The anthraquinone alizarin, the hydrolysis product of ruberythric acid, is supposed to be the main dye component of Rubia tinctorum. The chemical synthesis of alizarin and the biosynthesis of the anthraquinones in Rubia tinctorum are described. As far as the purification, structure elucidation and structures of isolated compounds are concerned, the review confines itself to the anthraquinones of madder. Finally the pharmacology and medicinal uses of madder and pure anthraquinones are discussed. This review supplements and updates earlier partial reviews on madder or anthraquinones by Schweppe, Thomson and Wijnsma. 

The roots of Rubia tinctorum have been used for dyeing textiles in many parts of the world since ancient times. Madder was widely cultivated in Western Europe for the dye industry until the beginning of the twentieth century. Rubia tinctorum contains useful anthraquinone mordant dyes. Dried roots of madder contain the hydroxy anthraquinones alizarin, pseudopurpurin, rubiadin, purpurin, purpuroxanthin and some minor anthraquinones. Anthraquinone derivatives are good mordant dyes if they satisfy the following conditions ... 

Anthraquinones and naphthoquinones are not exclusively formed via the polyketide biosynthetic route. They can also be derived from the shikimate pathway, e.g., the allelopathic naphthoquinone juglone from the walnut tree Juglans regia) and the anthraquinone alizarin from madder root Rubia tinctorium), which was used as purple dye. 

Quinones Anthraquinones Alizarin-1-methyl ether Schweppe Winter (1997)... 

Ashnagar, A. Naseri, N. Gharib Zadeh, A. S. Isolation and identification of l,2-dihydroxy-9,10-anthraquinone (alizarin) from the roots of maddar plant Rubia tinctorum). Int. J. Chem. Sci. 2007, 5, 683-688. 

Leistner, E., and M.H. Zenk Incorporation of Shikimic Acid into 1,2-Dihydroxy-anthraquinone (Alizarin) by Rubia tinctorum L. Tetrahedron Lett. 1967, 475. 

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