High Quality Content by WIKIPEDIA articles! Hydroxy-1,4-benzoquinone, also called hydroxy-para-benzoquinone, is an organic compound with formula C6H4O3, formally derived from 1,4-Benzoquinone by replacing one hydrogen atom with a hydroxyl (OH) group. It is one of three hydroxybenzoquinone isomers and one of the simplest hydroxyquinones.