{{Chembox <!-- Images --> | ImageFile = Daphnetin.svg | ImageSize = 200px | ImageAlt = <!-- Names --> | IUPACName = 7,8-Dihydroxy-2H-chromen-2-one | OtherNames = 7,8-Dihydroxycoumarin <!-- Sections --> | Section1 = {{Chembox Identifiers | CASNo = 486-35-1 | ChEBI = 17313 | ChEMBL = 244948 | ChemSpiderID = 4444191 | EC_number = 207-632-8 | PubChem = 5280569 | UNII = XC84571RD2 | KEGG = C03093 | StdInChI=1S/C9H6O4/c10-6-3-1-5-2-4-7(11)13-9(5)8(6)12/h1-4,10,12H | StdInChIKey = ATEFPOUAMCWAQS-UHFFFAOYSA-N | SMILES = C1=CC(=C(C2=C1C=CC(=O)O2)O)O }} | Section2 = {{Chembox Properties | C = 9 | H = 6 | O = 4 | Appearance = | Density = | MeltingPtC = 256 | MeltingPt_ref = <ref name=Merck>{{Cite book | title = Merck Index | edition = 11th | id = '''2816'''. Daphnetin | page = 2818 }}</ref> | BoilingPt = | Solubility = }} | Section3 = {{Chembox Hazards | GHS_ref=[https://pubchem.ncbi.nlm.nih.gov/compound/5280569#section=Safety-and-Hazards] | GHSPictograms = {{GHS07}} | GHSSignalWord = Warning | HPhrases = {{H-phrases|315|319}} | PPhrases = {{P-phrases|264|264+265|280|302+352|305+351+338|321|332+317|337+317|362+364 }} | MainHazards = | FlashPt = | AutoignitionPt = }} }}
'''Daphnetin''' is a chemical compound with the molecular formula {{chem2|C9H6O4}}. It has been isolated from plants of the genus ''Daphne''.<ref>{{cite journal | doi = 10.1107/S0567740876004275 | title = Daphnetin, isolated from ''Daphne odora'' | date = 1976 | last1 = Ueno | first1 = K. | last2 = Saito | first2 = N. | journal = Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry | volume = 32 | issue = 3 | pages = 946–948 | bibcode = 1976AcCrB..32..946U }}</ref><ref>{{cite journal | doi = 10.1515/znc-1986-0301 | title = Biosynthesis of Daphnetin in Daphne mezereum L | date = 1986 | last1 = Brown | first1 = Stewart A. | journal = Zeitschrift für Naturforschung C | volume = 41 | issue = 3 | pages = 247–252 | doi-access = free }}</ref> It has also been found in ''Matricaria chamomilla'' (chamomile).<ref name=":0">{{Cite journal |last1=Petruľová-Poracká |first1=Veronika |last2=Repčák |first2=Miroslav |last3=Vilková |first3=Mária |last4=Imrich |first4=Ján |date=2013-11-01 |title=Coumarins of ''Matricaria chamomilla'' L.: Aglycones and glycosides |url=https://www.sciencedirect.com/science/article/pii/S0308814613003051 |journal=Food Chemistry |language=en |volume=141 |issue=1 |pages=54–59 |doi=10.1016/j.foodchem.2013.03.004 |pmid=23768326 |issn=0308-8146|url-access=subscription }}</ref>
It a crystalline solid with a melting point of 256 °C.<ref name=Merck/> It is soluble in boiling water.<ref name=Merck/>
Daphnetin can undergo enzymatic glycosylation to yield its 7-''O''-glucoside which is called daphnin (daphnetin 7-β-<small>D</small>-glucopyranoside). The reaction is catalyzed by the enzyme O-dihydroxycoumarin 7-O-glucosyltransferase. The glucose unit is transferred from UDP-glucose, with uridine diphosphate (UDP) as byproduct.<ref>{{Cite journal |last1=Ibrahim |first1=Ragai K. |last2=Boulay |first2=Bernard |date=1980-05-01 |title=Purification and some properties of UDP-glucose:o-dihydroxycoumarin7-O-glucosyltransferase from tobacco cell cultures |journal=Plant Science Letters |language=en |volume=18 |issue=2 |pages=177–184 |doi=10.1016/0304-4211(80)90048-6 |issn=0304-4211 }}</ref><ref>{{Cite journal |last1=Ueno |first1=Katsuhiko |last2=Sato |first2=Mitsuhiko |last3=Saito |first3=Norio |date=1983-06-01 |title=The Crystal and Molecular Structure of Daphnin Dihydrate: 7-(β-D-Glucopyranosyloxy)-8-hydroxycoumarin Dihydrate |journal=Bulletin of the Chemical Society of Japan |volume=56 |issue=6 |pages=1577–1580 |doi=10.1246/bcsj.56.1577 |issn=0009-2673 |doi-access=free}}</ref>
{{chemrxn|width=55%| {{chemrxn/cpd|daphnetin }} {{chemrxn/txt|+ UDP-glucose }} {{chemrxn/arw|fwd_out=UDP }} {{chemrxn/cpd|daphnin|upright=1.6 }} }}
Daphnetin shows several neuroprotective and anti-inflammatory effects on the inhibition of the TLR4/NF-κB mediated inflammatory signaling pathway. They also could inhibit the IKKs/IkBa/NF-κB, AKT, and the Src/FAK/ERK1/2 multi-target medication signaling pathway for anti-angiogenesis and cancer.<ref>{{Cite journal |last1=Liu |first1=Jia |last2=Chen |first2=Qianxue |last3=Jian |first3=Zhihong |last4=Xiong |first4=Xiaoxing |last5=Shao |first5=Lingmin |last6=Jin |first6=Tong |last7=Zhu |first7=Xiqun |last8=Wang |first8=Lei |date=2016-12-29 |title=Daphnetin Protects against Cerebral Ischemia/Reperfusion Injury in Mice via Inhibition of TLR4/NF-κB Signaling Pathway |journal=BioMed Research International |language=en |volume=2016 |article-number=e2816056 |doi=10.1155/2016/2816056 |issn=2314-6133 |pmc=5227117 |pmid=28119924 |doi-access=free}}</ref>
Daphnetin has been reported to be a strong sensitizer, which means that this compound and its glycosidic derivatives (e.g. daphnin) can be a cause of allergic reactions.<ref name=":0" />
==References== {{reflist}}
Category:Coumarins Category:Polyphenols Category:Diols