A dihydroxynaphthoquinone (formula: ) is any of several organic compounds that can be viewed as derivatives of naphthoquinone through replacement of two hydrogen atoms (H) by hydroxyl groups (OH).
The unqualified term "dihydroxynaphthoquinone" usually means a derivative of 1,4-naphthoquinone. Other dihydroxy- compounds can be derived from the two other known isomers, 1,2-naphthoquinone (ortho-) and 2,6-naphthoquinone (amphi-).
Isomers From 1,4-naphthoquinone Due to the symmetry of the parent quinone, there are only nine distinct isomers of dihydroxy-1,4-naphthoquinone: 2,3-Dihydroxy-1,4-naphthoquinone. 2,5-Dihydroxy-1,4-naphthoquinone. 2,6-Dihydroxy-1,4-naphthoquinone. 2,7-Dihydroxy-1,4-naphthoquinone. 2,8-Dihydroxy-1,4-naphthoquinone. 5,6-Dihydroxy-1,4-naphthoquinone. 5,7-Dihydroxy-1,4-naphthoquinone. 5,8-Dihydroxy-1,4-naphthoquinone (naphthazarin). J. Khalafy and J.M. Bruce (2002), Oxidative dehydrogenation of 1-tetralones: Synthesis of juglone, naphthazarin, and α-hydroxyanthraquinones. Journal of Sciences, Islamic Republic of Iran, volume 13 issue 2, pages 131-139. 6,7-Dihydroxy-1,4-naphthoquinone.
From 1,2-naphthoquinone From 1,2-naphthoquinone there are 12 possible dihydroxy- isomers: 3,4-Dihydroxy-1,2-naphthoquinone 3,5-Dihydroxy-1,2-naphthoquinone 3,6-Dihydroxy-1,2-naphthoquinone 3,7-Dihydroxy-1,2-naphthoquinone 3,8-Dihydroxy-1,2-naphthoquinone 4,5-Dihydroxy-1,2-naphthoquinone 4,6-Dihydroxy-1,2-naphthoquinone 4,7-Dihydroxy-1,2-naphthoquinone 4,8-Dihydroxy-1,2-naphthoquinone 5,6-Dihydroxy-1,2-naphthoquinone 5,7-Dihydroxy-1,2-naphthoquinone 5,8-Dihydroxy-1,2-naphthoquinone 6,7-Dihydroxy-1,2-naphthoquinone 6,8-Dihydroxy-1,2-naphthoquinone 7,8-Dihydroxy-1,2-naphthoquinone
From 2,6-naphthoquinone From the symmetrical 2,6-naphthoquinone there are only nine dihydroxy- isomers: 1,3-Dihydroxy-2,6-naphthoquinone 1,4-Dihydroxy-2,6-naphthoquinone 1,5-Dihydroxy-2,6-naphthoquinone 1,7-Dihydroxy-2,6-naphthoquinone 1,8-Dihydroxy-2,6-naphthoquinone 3,4-Dihydroxy-2,6-naphthoquinone 3,7-Dihydroxy-2,6-naphthoquinone 3,8-Dihydroxy-2,6-naphthoquinone 4,8-Dihydroxy-2,6-naphthoquinone
See also Hydroxynaphthoquinone Trihydroxynaphthoquinone Dihydroxyanthraquinone
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