For the parent molecule 9,10-anthraquinone, see anthraquinone
Anthraquinones (also known as anthraquinonoids) are a class of naturally occurring phenolic compounds based on the 9,10-anthraquinone skeleton. They are widely used industrially and occur naturally.
The name "anthraquinone" was first used by German chemists Carl Graebe and Carl Theodore Liebermann in a 1868 publication describing the chemical synthesis of the red dye alizarin from anthracene, a component of coal tar. This discovery led to the industrial production of alizarin and the impetus for further research on anthraquinone chemistry.
Occurrence in plants
- (here Variospora thallincola), is due to the presence of anthraquinones.
Natural
that are derivatives of anthraquinone are found, inter alia, in aloe latex, senna,
rhubarb, and cascara buckthorn,
fungi,
, and some
. A type II polyketide synthase is responsible for anthraquinone biosynthesis in the bacterium
Photorhabdus luminescens.
, formed by isochorismate synthase in the shikimate pathway, is a precursor of anthraquinones in
Morinda citrifolia.
Tests for anthraquinones in natural extracts have been established.
Applications
In the production of hydrogen peroxide
A large industrial application of anthraquinones is for the production of hydrogen peroxide. 2-Ethyl-9,10-anthraquinone or a related alkyl derivative is used, rather than anthraquinone itself.
Millions of tons of hydrogen peroxide are manufactured by the anthraquinone process.
Pulping
Sodium 2-anthraquinonesulfonate (AMS) is a water-soluble anthraquinone derivative that was the first anthraquinone derivative discovered to have a catalytic effect in the alkaline pulping processes.
Dyestuff precursor
The 9,10-anthraquinone skeleton occurs in many dyes, such as
alizarin.
Important derivatives of 9,10-anthraquinone are 1-nitroanthraquinone, anthraquinone-1-sulfonic acid, and the dinitroanthraquinone.
. From the left: C.I.Acid Blue 43
an "acid dye" for wool (also called "Acilan Saphirol SE"), C.I. Vat Violet 1, which is applied by transfer printing using sublimation, a blue colorant commonly used in gasoline, and C.I. Disperse Red 60.]]
Medicine
Derivatives of 9,10-anthraquinone include drugs such as the anthracenediones and the
anthracycline family of
chemotherapy drugs. The latter drugs are derived from the bacterium
Streptomyces peucetius, discovered in a soil sample near the
Adriatic Sea. Drugs in the anthraquinone family include the prototypical
daunorubicin,
doxorubicin,
mitoxantrone,
losoxantrone, and
pixantrone. Most of these drugs, with the notable exception of pixantrone, are extremely cardiotoxic, causing irreversible
cardiomyopathy, which can limit their practical usefulness in
cancer treatment.
[
]
The anthracenediones also include
-
such as rufigallol
-
DNA dyes / nuclear counterstains such as DRAQ5, DRAQ7 and CyTRAK Orange for flow cytometry and fluorescence microscopy.
-
Anthraquinone derivatives: rhein, emodin, aloe emodin, parietin (physcion), and chrysophanol extracted from Cassia occidentalis are toxic and known to cause hepatomyoencephalopathy in children.
- ]]
Dantron, emodin, and aloe emodin, and some of the senna glycosides have laxative effects. Prolonged use and substance abuse leads to melanosis coli.
Flow batteries
Soluble anthraquinones such as 9,10-anthraquinone-2,7-disulfonic acid are used as reactants in Flow battery, which provide electrical energy storage.
