{{chembox | ImageFile = Homoorientin.svg | ImageSize = 250px | IUPACName = 6-(β-<small>D</small>-Glucopyranosyl)-3′,4′,5,7-tetrahydroxyflavone | SystematicName = 2-(3,4-Dihydroxyphenyl)-5,7-dihydroxy-6-[(2''S'',3''R'',4''R'',5''S'',6''R'')-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]-4''H''-1-benzopyran-4-one | OtherNames = Luteolin-6-C-glucoside<br>Homoorientin |Section1={{Chembox Identifiers | CASNo_Ref = | CASNo = 4261-42-1 | UNII_Ref= {{fdacite|correct|FDA}} | UNII = A37342TIX1 | InChI = 1S/C21H20O11/c22-6-14-17(27)19(29)20(30)21(32-14)16-11(26)5-13-15(18(16)28)10(25)4-12(31-13)7-1-2-8(23)9(24)3-7/h1-5,14,17,19-24,26-30H,6H2/t14-,17-,19+,20-,21+/m1/s1 | InChIKey = ODBRNZZJSYPIDI-VJXVFPJBSA-N | PubChem = 114776 | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEBI = 17965 | KEGG_Ref = {{keggcite|correct|kegg}} | KEGG = C01821 | ChemSpiderID = 102753 | ChEMBL_Ref = | ChEMBL = | SMILES = C1=CC(=C(C=C1C2=CC(=O)C3=C(C(=C(C=C3O2)O)C4C(C(C(C(O4)CO)O)O)O)O)O)O }} |Section2={{Chembox Properties | C=21 | H=20 | O=11 | Appearance= | Density= | MeltingPt= | BoilingPt= | Solubility= }} |Section3={{Chembox Hazards | MainHazards= | FlashPt= | AutoignitionPt = }} }}
'''Isoorientin''' ('''homoorientin''') is a flavone, a chemical flavonoid-like compound. It is the luteolin-6-''C''-glucoside.
== Natural occurrence == Isoorientin can be isolated from the passion flower,<ref>{{cite journal | doi = 10.1002/cbdv.201300181 | title = Glycosidic Inhibitors of Melanogenesis from Leaves of ''Passiflora edulis'' | date = 2013 | last1 = Zhang | first1 = Jie | last2 = Koike | first2 = Ryosuke | last3 = Yamamoto | first3 = Ayako | last4 = Ukiya | first4 = Motohiko | last5 = Fukatsu | first5 = Makoto | last6 = Banno | first6 = Norihiro | last7 = Miura | first7 = Motofumi | last8 = Motohashi | first8 = Shigeyasu | last9 = Tokuda | first9 = Harukuni | last10 = Akihisa | first10 = Toshihiro | journal = Chemistry & Biodiversity | volume = 10 | issue = 10 | pages = 1851–1865 | pmid = 24130028 }}</ref> ''Vitex negundo'',<ref>{{cite journal | doi = 10.1016/j.bmcl.2006.09.051 | title = New antifungal flavonoid glycoside from Vitex negundo | date = 2007 | last1 = Sathiamoorthy | first1 = B. | last2 = Gupta | first2 = Prasoon | last3 = Kumar | first3 = Manmeet | last4 = Chaturvedi | first4 = Ashok K. | last5 = Shukla | first5 = P.K. | last6 = Maurya | first6 = Rakesh | journal = Bioorganic & Medicinal Chemistry Letters | volume = 17 | issue = 1 | pages = 239–242 | pmid = 17027268 }}</ref> ''Terminalia myriocarpa'', the Açaí palm, and ''Swertia japonica''.
== Potential pharmacology== Isoorientin has been studied for its potential pharmacological activity.<ref>{{Cite journal | doi = 10.1016/j.phrs.2020.104867 | title = Isoorientin: A dietary flavone with the potential to ameliorate diverse metabolic complications | date = 2020 | last1 = Ziqubu | first1 = Khanyisani | last2 = Dludla | first2 = Phiwayinkosi V. | last3 = Joubert | first3 = Elizabeth | last4 = Muller | first4 = Christo J.F. | last5 = Louw | first5 = Johan | last6 = Tiano | first6 = Luca | last7 = Nkambule | first7 = Bongani B. | last8 = Kappo | first8 = Abidemi P. | last9 = Mazibuko-Mbeje | first9 = Sithandiwe E. | journal = Pharmacological Research | volume = 158 | pmid = 32407953 }}</ref> Bioassay-directed fractionation techniques led to isolation of isoorientin as the main hypoglycaemic component in ''Gentiana olivieri''.<ref>Hypoglycaemic activity of Gentiana olivieri and isolation of the active constituent through bioassay- directed fractionation techniques. Ekrem Sezik, Mustafa Aslan, Erdem Yesilada, Shigeru Ito, Life Sciences, 28 January 2005, Volume 76, Issue 11, Pages 1223–1238, {{doi|10.1016/j.lfs.2004.07.024}}</ref> Studies also showed that isoorientin is a potential neuroprotective compound against Alzheimer's disease.<ref>{{cite journal |author1=Zhibin Liang |author2=Bei Zhang |author3=Wei Wen Su |author4=Philip G Williams |author5=Qing X Li |title=C-Glycosylflavones Alleviate Tau Phosphorylation and Amyloid Neurotoxicity through GSK3β Inhibition |journal=ACS Chemical Neuroscience |volume=7 |date=July 2016 |issue=7 |pages=912–923 |pmid=27213824 |doi=10.1021/acschemneuro.6b00059 |pmc=7355085 }}</ref>
== Metabolism == The enzyme isoorientin 3'-O-methyltransferase converts isoorientin to isoscoparin in a methylation reaction using the cofactor, S-adenosyl methionine (SAM):<ref>{{cite journal |last1=Van Brederode |first1=J. |last2=Kamps-Heinsbroek |first2=R. |last3=Mastenbroek |first3=O. |title=Biochemical and Ontogenetic Evidence that the Ferulic Acid and Isoscoparin Formation in Silene are Catalyzed by Different Enzymes |journal=Zeitschrift für Pflanzenphysiologie |date=1982 |volume=106 |pages=43–53 |doi=10.1016/S0044-328X(82)80053-6 }}</ref>
{{chemrxn|width=70%| {{chemrxn/cpd|isoorientin }} {{chemrxn/txt|+ SAM }} {{chemrxn/arw| }} {{chemrxn/cpd|qid=Q27102895|caption=isoscoparin }} {{chemrxn/txt|+ SAH }} }}
== See also== * Orientin, the 8-C glucoside of luteolin.
== References == {{Reflist}}
{{flavone}}
Category:Flavone glucosides Category:C-glycoside natural phenols