title: O-methylated flavonoid
text: # O-methylated flavonoid
  
  The O-methylated flavonoids or methoxyflavonoids are flavonoids with methylations on hydroxyl groups (methoxy bonds). O-methylation has an effect on the solubility of flavonoids.
  
  ## Enzymes
  
  O-methylated flavonoids formation implies the presence of specific O-methyltransferase (OMT) enzymes which accept a variety of substrates. Those enzymes mediate the O-methylation on a specific hydroxyl group, like on 4' (example in Catharanthus roseus) or 3' (example in rice) positions. Those positions can be ortho, meta, para and there can be a special 3-O-methyltransferase for the 3-OH position. Calamondin orange (Citrus mitis) exhibits all of those activities.
  
  ### Plant enzymes
  
  * Apigenin 4'-O-methyltransferase
  * 8-hydroxyquercetin 8-O-methyltransferase
  * Isoflavone 4'-O-methyltransferase
  * Isoflavone 7-O-methyltransferase
  * Isoliquiritigenin 2'-O-methyltransferase
  * Isoorientin 3'-O-methyltransferase
  * Kaempferol 4'-O-methyltransferase
  * Luteolin O-methyltransferase
  * Methylquercetagetin 6-O-methyltransferase
  * 3-methylquercetin 7-O-methyltransferase
  * Myricetin O-methyltransferase
  * Quercetin 3-O-methyltransferase
  * Vitexin 2"-O-rhamnoside 7-O-methyltransferase
  
  ### Animal enzyme
  
  * Catechol-O-methyl transferase
  
  ## O-methylated anthocyanidins
  
  * 5-Desoxy-malvidin
  * Capensinidin
  * Europinidin
  * Hirsutidin
  * Malvidin
  * Peonidin
  * Petunidin
  * Pulchellidin
  * Rosinidin
  
  ## O-methylated flavanols
  
  * Meciadanol (3-O'methyl catechin)
  
  ## O-methylated flavanones
  
  * Hesperetin
  * Homoeriodictyol
  * Isosakuranetin
  * Sakuranetin
  * Sterubin
  
  ## O-methylated flavanonols
  
  * Dihydrokaempferide
  
  ## O-methylated flavonols
  
  of kaempferol
  
  * Kaempferide
  
  of myricetin
  
  * Annulatin
  * Combretol
  * Europetin
  * Laricitrin (3'-O-Dimethylmyricetin)
  * 5-O-methylmyricetin
  * Syringetin (3',5'-O-Dimethylmyricetin)
  
  of quercetin
  
  * Ayanin
  * Azaleatin
  * Isorhamnetin
  * Ombuin
  * Pachypodol
  * Retusin (quercetin-3,7,3',4'-tetramethyl ether)
  * Rhamnazin
  * Rhamnetin
  * Tamarixetin
  
  other
  
  * Eupatolitin
  * Natsudaidain
  
  ## O-methylated flavones
  
  * Acacetin
  * Chrysoeriol
  * Diosmetin
  * Nepetin
  * Nobiletin
  * Oroxylin-A
  * Sinensetin
  * Tangeritin
  * Thevetiaflavone
  * Wogonin
  
  ## O-methylated isoflavones
  
  * Biochanin A
  * Calycosin
  * Formononetin
  * Glycitein
  * Irigenin
  * 5-O-methylgenistein
  * Pratensein
  * Prunetin
  * Psi-tectorigenin
  * Retusin
  * Tectorigenin
  