Ombuin is an O-methylated flavonol, a type of flavonoid. It is the 4',7-O-methyl derivative of quercetin

Quercetin

Quercetin , a flavonol, is a plant-derived flavonoid found in fruits, vegetables, leaves and grains. It also may be used as an ingredient in supplements, beverages or foods.-Occurrence:...

.

Ombuin can be found in species of the genus Erythroxylum

Erythroxylum

Erythroxylum is a genus of tropical flowering plants in the family Erythroxylaceae. Many species contain the drug cocaine; Erythroxylum coca, a native of South America, is the main commercial source of cocaine and of the mild stimulant coca tea...

. It can also be synthetized. Ombuin 3-sulfate can be isolated from Flaveria chloraefolia.

Glycosides

Ombuin-3-rutinoside can be isolated from Phytolacca dioica, the ombu tree. Ombuin-3-O-rhamnosylglucoside can be found in Erythroxylum rufum.

Other glycosides (ombuosides) :

• Ombuin 3-galactoside (C₂₃H₂₄O₁₂, CAS number 69168-13-4)
• Ombuin 3-glucoside (C₂₃H₂₄O₁₂, CAS number 158642-42-3)