Benzoquinone

Benzoquinone is a quinone with a single benzene ring, of which there are only two:
 * 1,4-Benzoquinone, most commonly (also para-benzoquinone, p-benzoquinone, para-quinone, or just quinone)
 * 1,2-Benzoquinone, less commonly (also ortho-benzoquinone, o-benzoquinone, ortho-quinone)

Benzoquinone Benzoquinona