6-hydroxymelatonin 6-hydroxymelatonin 6-hydroxymelatonin (6-ohm) is a naturally occurring, endogenous, major active metabolite of melatonin. similar to melatonin, 6-ohm is a full agonist of the mt1 and mt2 receptors. it is also an antioxidant and neuroprotective, and is even more potent in this regard relative to melatonin. 6-hydroxymelatonin names preferred iupac name n-acetamide other names 6-oxymelatonin identifiers cas number 2208-41-5 y 3d model (jsmol) interactive image chebi chebi:198 chemspider 1794 echa infocard 100.164.426 kegg c05643 pubchem cid 1864 unii tv437t5077 y comptox dashboard (epa) dtxsid00176577 inchi inchi=1s/c13h16n2o3/c1-8(16)14-4-3-9-7-15-11-6-12(17)13(18-2)5-10(9)11/h5-7,15,17h,3-4h2,1-2h3,(h,14,16)key: omymrcxojjzyke-uhfffaoysa-ninchi=1/c13h16n2o3/c1-8(16)14-4-3-9-7-15-11-6-12(17)13(18-2)5-10(9)11/h5-7,15,17h,3-4h2,1-2h3,(h,14,16)key: omymrcxojjzyke-uhfffaoyak smiles cc(=o)nccc1=cnc2=cc(=c(c=c21)oc)o properties chemical formula c13h16n2o3 molar mass 248.282 g·mol−1 except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). infobox references