Chemical Properties
orange-red crystals or powder
History
In ancient times, alizarin was the preferred red dye. Cloth dyed with it has been found in Egyptian tombs dating 6000 years ago. The dye is found in the madder plant, a member of the Rubiaceae family. In 1944 about 35 species of this plant were known, but the use of more sophisticated analytical methods led to the detection of many more species; by 1984 the number had increased to 50. Alizarin is a mordant dye forming various colored coordination complexes with different metallic salts.
Uses
Alizarin has a major application in the manufacture of the madder lake pigments which is commonly called as Rose madder and Alizarin crimson. It is involved in the studies of bone growth, osteoporosis, bone marrow and calcium deposits in the vascular system. It is also used as a stain in calcite and aragonite to identify calcium carbonate, and synovial fluid to asses for basic calcium phosphate crystals. It is used in colorimetric measurements for quantification of amine extraction by model food simulants from epoxy polymer.
Uses
Alizarin is used widely as a prominent red dye for textile facbrics. Alizarin red is now used in biochemical assay to determine quantitatively by colorimetry, the presence of calcific deposition by ce
lls of the osteogenic lineage. Alzarine derivatives was evaluated as new inhibitors of the HIV-1 reverse transcriptase associated DNA polymerase and RNase H. Alizarin was also shown to inhibit prolife
ration, tumor growth and suppress tumorigenesis in human osteosarcoma and breast cancer cell representative for bone metastasis.
Definition
alizarin: An orange-red compound,C14H8O4. The compound is a derivativeof anthraquinone, with hydroxylgroups substituted at the 1and 2 positions. It is an importantdyestuff producing red or violetlakes with metal hydroxide.Alizarin occurs naturally as the glucosidein madder. It can be synthesizedby heating anthraquinone withsodium hydroxide.
Definition
An important orange-red
organic compound used in the dyestuffs industry
to produce red lakes. It occurs naturally
in the root of the plant madder and
may also be synthesized from anthraquinone.
Definition
ChEBI: A dihydroxyanthraquinone that is anthracene-9,10-dione in which the two hydroxy groups are located at positions 1 and 2.
Preparation
(a) 2 – Bromoanthraquinone and Potassium hydroxide heating; (b) 9,10-Dioxo-9,10-dihydroanthracene-2-sulfonic acid (Sodium) and Sodium hydroxide and Sodium nitrate and Sodium chlorate heating; (C) Anthracene-9,10-dione?and Sodium hydroxide and Sodium chlorate and Sodium nitrate heating (GP 186526); (d) in the presence of Sodium nitrite and Sodium hydroxide and Anthracene-9,10-dione?and Sodium nitrate heating (GP 241806245 987); (e) in the Oxidant and Sodium sulfite and the presence of lime, anthracene in a nitrocellulose derivatives and Sodium hydroxide heating (GP 292247); (f) 2 – Anthraquinonesulfonic acid in the presence of air, with the Sodium hydroxide Etanol wetting treatment (GP 287270); (g) 2-Chloroanthracene-9,10-dione Sodium chlorate in the presence of alkali fusion for (USP 1744815); (h) 2-Methylanthracene-9,10-dione in the presence of Oxidant, with Sodium hydroxide treatment (BP 293328).
Biological Activity
alizarin is an anthraquinone dye for detecting the presence of calcium salts [1].alizarin belongs to the anthraquinone group. it is a chelator for calcium and is commonly used to stain the calcifying or calcio-receptive zone of the collagenous matrix where calcium salts are being deposited. on the other hand, the alizarin complexone is used for bone staining in vivo to study bone remodeling [1].alizarin is proved to have anti-tumor efficacy. it suppresses the cell growth of the prostate cancer, breast cancer and osteosarcoma cell lines in vitro. among these, the osteosarcoma cells appear to be most sensitive. the ic50 values of alizarin against three osteosarcoma cell lines saos-2, mg-63 and u-2 os are 27.5, 29 and 69.9μg/ml, respectively. alizarin inhibits the cell growth through cell proliferation blockade rather than induction of apoptosis. it inhibits the phosphorylation of erk. in addition, alizarin is also found to induce s-phase arrest as well as a decrease of the g0/g1 and g2/m phases [1].
Synthesis
1,2-Dihydroxyanthraquinone is
prepared from anthraquinone by alkali melt
or from anthraquinone-2-sulfonic acid
with 50 % aqueous sodium hydroxide and
sodium nitrate at 190 – 200 ?C .
Properties and Applications
commonly known as 1,2-Dihydroxyanthracene-9,10-dione , calcium, aluminum mordanting for red to blue light red, chromium for dark blue light red, iron as dark purplish red. Claybank powder. Slightly soluble in water, but soluble in Methanol, Acetone Etanol, boiling, alkali and Cellosolve, slightly soluble in benzene, Carbon tetrachloride, insoluble in cold Etanol, Stout solvent, soluble in alkali liquor for royal purple. In concentrated sulfuric acid for yellow red, red yellow after diluted produce precipitation; In the Sodium hydroxide to purple. Used for wool fabric dyeing and used as organic pigment.
Standard
|
Ironing Fastness
|
Light Fastness
|
Fulling
|
Persperation Fastness
|
Soaping
|
Water
|
Alkali
|
Acid
|
ISO
|
3-4
|
7
|
3-4
|
1
|
3
|
4
|
4
|
AATCC
|
Dry 2,wet 5
|
7
|
2-3
|
|
4
|
4
|
5
|
Purification Methods
Alizarin crystallises from glacial acetic acid or 95% EtOH. It can also be sublimed at 110o/2mm. It is an indicator with max at 452nm (pH 5.8) and 520nm (pH 7.2). [Beilstein 8 IV 3256.]
References
[1] fotia c, avnet s, granchi d, baldini n. the natural compound alizarin as an osteotropic drug for the treatment of bone tumors. j orthop res. 2012 sep;30(9):1486-92.