Ombuin

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

Ombuin

Names
IUPAC name 3,3′,5-Trihydroxy-4′,7-dimethoxyflavone
Systematic IUPAC name 3,5-Dihydroxy-2-(3-hydroxy-4-methoxyphenyl)-7-methoxy-4H-1-benzopyran-4-one
Other names 4′,7-Dimethylquercetin 7,4′-Di-O-methylquercetin 4′,7-Dimethoxy-3,3′,5-trihydroxyflavone
Identifiers
CAS Number	529-40-8 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:67493 N
ChemSpider	4478412 N
PubChem CID	5320287
UNII	Z3K3F0YR3W Y
CompTox Dashboard (EPA)	DTXSID00200942
InChI InChI=1S/C17H14O7/c1-22-9-6-11(19)14-13(7-9)24-17(16(21)15(14)20)8-3-4-12(23-2)10(18)5-8/h3-7,18-19,21H,1-2H3 N Key: BWORNNDZQGOKBY-UHFFFAOYSA-N N InChI=1/C17H14O7/c1-22-9-6-11(19)14-13(7-9)24-17(16(21)15(14)20)8-3-4-12(23-2)10(18)5-8/h3-7,18-19,21H,1-2H3 Key: BWORNNDZQGOKBY-UHFFFAOYAW
SMILES COC1=C(C=C(C=C1)C2=C(C(=O)C3=C(C=C(C=C3O2)OC)O)O)O
Properties
Chemical formula	C17H14O7
Molar mass	330.29 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Ombuin can be found in species of the genus Erythroxylum. It can also be synthesized.^[1] Ombuin 3-sulfate can be isolated from Flaveria chlorifolia.^[2]

Glycosides

Ombuin-3-rutinoside can be isolated from Phytolacca dioica, the ombu tree.^[3] Ombuin-3-O-rhamnosylglucoside can be found in Erythroxylum rufum.^[4]
Other glycosides (ombuosides) :

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

References

1. Partial methylation of quercetin: Direct synthesis of tamarixetin, ombuin and ayanin. Koppaka V. Rao, Jacob A. Owoyale, Journal of Heterocyclic Chemistry, Volume 13 Issue 6, Pages 1293 - 1295^{[dead link]}
2. Ombuin 3-sulphate from Flaveria chloraefolia. Denis Barron and Ragai K. Ibrahim, Phytochemistry, Volume 27, Issue 7, 1988, pages 2362-2363, doi:10.1016/0031-9422(88)80166-3
3. Über die Synthese von Quercetin-3-glykosiden, II. Synthese des Ombuosids und eine rationelle Synthese von Rutin. Ludwig Hörhammer, Hildebert Wagner, Hans-Günther Arndt, Gustav Hitzler, Lorand Farkas, Chemische Berichte, Volume 101 Issue 4, Pp 1183-1185, 1968 (German)
4. Flavonoids of Erythroxylum rufum and Erythroxylum ulei. Bruce A. Bohm, David W. Phillips and Fred R. Gander, J. Nat. Prod., 1981, volume 44, issue 6, pages 676–679, doi:10.1021/np50018a009