Hexahydroxy-1,4-naphthalenedione
Introduction '''Spinochrome E''', '''2,3,5,6,7,8-Hexahydroxy-1,4-naphthalenedione''', also called '''hexahydroxynaphthoquinone'''  is a polyhydroxylated 1,4-naphthoquinones,  pigments found in sea urchin shell ("test"), spine, gonads, coelomic fluid, and eggs, of sea urchin commonly known as spinochromes. These natural phenolic compounds are quinones that are known to have pharmacological properties. The several hydroxyl groups are appropriate for free-radical scavenging, which diminishes ROS and prevents redox imbalance. Mechanisms are described such as scavenging of reactive oxygen species (ROS), interaction with lipid peroxide radicals, chelation of metal ions, inhibition of lipid peroxidation and regulation of the cell redox potential. Spinochrome E formula  shows that have one extra hydroxyl group that Echinochrome A and it is formally derived from naphthoquinone (1,4-naphtalenedione) through replacement of all six hydrogen atoms by hydroxyl (OH) groups. The numerical prefixes "2,3,5,6,7,8" are superfluous, since there is no other hexahydroxy derivative of 1,4-naphthoquinone.Spinochrome from sea urchins, in oriental culture, are known for its health benefits. The sea urchin appears in the "Materia medica" of the Ming Dynasty author by Li Zhongli in 1647 and the benefits cited are for the heart, bones, blood and also it counteracts impotence. Today it is known the benefits for the health of these compounds.The compound can be produced by condensation of 3,4,5,6-tetramethoxyphthalaldehyde with glyoxal.
See also * Hexahydroxy-2,3-naphthalenedione, a structural isomer. * Tetrahydroxybenzoquinone* Octahydroxyanthraquinone
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