A dihydroxynaphthoquinone (formula: C10H6O4) 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-).
Due to the symmetry of the parent quinone, there are only nine distinct isomers of dihydroxy-1,4-naphthoquinone: From 1,2-naphthoquinone there are 12 possible dihydroxy- isomers: From the symmetrical 2,6-naphthoquinone there are only nine dihydroxy- isomers: