In enzymology, a flavonol synthase is an enzyme that catalyzes the following chemical reaction : dihydroflavonol + 2-oxoglutarate + a flavonol + succinate + C + H2O The 3 substrates of this enzyme are dihydroflavonol, 2-oxoglutarate, and O2, whereas its 4 products are flavonol, succinate, CO2, and H2O. This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from with 2-oxoglutarate as one donor, and incorporation of one atom of oxygen into each donor. The systematic name of this enzyme class is dihydroflavonol,2-oxoglutarate:oxygen oxidoreductase. This enzyme participates in flavonoid biosynthesis.