From Bioblast
Description
Quinol is a class of reduced organic compounds derived from quinone (oxidized form) by two-electron and two-proton reduction in aqueous medium. In the mitochondrial electron transfer system, ubiquinol or coenzyme Q occur, while in the photosynthetic systems plastoquinols are common. These redox compounds exist in three different forms: quinone (oxidized), quinol (reduced), and an intermediate semiquinone.
Reference: Wolf 1958 J Am Chem Soc, Crane 1956 Biochim Biophys Acta, Havaux 2020 Trends Plant Sci