Flavonols

thumb|200px|Backbone of a flavonol, substituent numbers are indicated. Flavonols are a class of flavonoids that have the 3-hydroxyflavone backbone (IUPAC name: 3-hydroxy-2-phenylchromen-4-one). Their diversity stems from the different positions of the phenolic –OH groups. They are distinct from flavanols (with "a") such as catechin, another class of flavonoids, and an unrelated group of metabolically important molecules, the flavins (with "i"), derived from the yellow B vitamin riboflavin.

chemical compound

Myricetin is a member of the flavonoid class of polyphenolic compounds, with antioxidant properties. Common dietary sources include vegetables (including tomatoes), fruits (including oranges), nuts, berries, tea, and red wine.

Fisetin (7,3′,4′-flavon-3-ol) is a plant flavonol from the flavonoid group of polyphenols. It occurs in many plants where it serves as a yellow pigment. It is found in many fruits and vegetables, such as strawberries, apples, persimmons, onions, and cucumbers.

Galangin is a flavonol, a type of flavonoid.

3-Hydroxyflavone is a chemical compound. It is the backbone of all flavonols, a type of flavonoid. It is a synthetic compound, which is not found naturally in plants. It serves as a model molecule as it possesses an excited-state intramolecular proton transfer (ESIPT) effect to serve as a fluorescent probe to study membranes for example or intermembrane proteins. The green tautomer emission (λmax ≈ 524 nm) and blue-violet normal emission (λmax ≈ 400 nm) originate from two different ground state populations of 3HF molecules. The phenomenon also exists in natural flavonols. Although 3-

Gossypetin, also known as '''3,5,7,8,3',4'-hexahydroxyflavone', is a flavonol, a type of flavonoid. It has been isolated from the flowers and the calyx of Hibiscus sabdariffa'' (roselle) and exhibits a strong antibacterial activity. The compound has also been found to act as an antagonist of TrkB. Gossypetin has radioprotective activity.

Karanjin is a furanoflavonol, a type of flavonoid. It is obtained from the seeds of the karanja tree (Millettia pinnata or Pongamia glabra Vent.), a tree growing wild in south India. Karanjin is an acaricide and insecticide. Karanjin is reported to have nitrification inhibitory properties. Its formula was discovered by D. B. Limaye.

Herbacetin is a flavonol, a type of flavonoid.

Quercetagetin is a flavonol, a type of flavonoid. It can be found in the genus Eriocaulon.

Juglanin is a flavonol found in Polygonum aviculare.

Karanjachromene is a pyranoflavonol, a type of flavonol. It is a fluorescent pyranoflavonoid isolated from the seed oil of Millettia pinnata.

Tamarixetin is an O-methylated flavonol, a naturally occurring flavonoid. It has been isolated from Tamarix ramosissima.