Purpurogallin

Purpurogallin is an aglycone natural product. It is an orange-red solid that is soluble in polar organic solvents but not in water. Its glycoside (ether-linked to sugar), called dryophantin, is found in nutgalls and oak barks. Purpurogallin can be prepared by oxidation of pyrogallol with sodium periodate.^[1]

Purpurogallin

Chemical structure of purpurogallin
Names
Preferred IUPAC name 1,7,8,9-Tetrahydroxy-2H-benzo[7]annulen-2-one
Other names Purpurogalline 2,3,4,6-Tetrahydroxybenzocyclohepten-5-one PPG
Identifiers
CAS Number	569-77-7 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:8647 N
ChemSpider	4444893 N
ECHA InfoCard	100.008.478
KEGG	C09964 N
MeSH	C026133
PubChem CID	5281571
UNII	L3Z7U4N28P Y
CompTox Dashboard (EPA)	DTXSID40205436
InChI InChI=1S/C11H8O5/c12-6-3-1-2-5-4-7(13)10(15)11(16)8(5)9(6)14/h1-4,13,15-16H,(H,12,14) N Key: WDGFFVCWBZVLCE-UHFFFAOYSA-N N
SMILES C1=CC(=O)C(=C2C(=C1)C=C(C(=C2O)O)O)O
Properties
Chemical formula	C11H8O5
Molar mass	220.180 g·mol−1
Appearance	Red crystalline solid
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

Medicinal aspects

Purpurogallin is bioactive^[2] It can inhibit 2-hydroxy and 4-hydroxyestradiol methylation by catechol-O-methyltransferase.^[3] It potently and specifically inhibits TLR1/TLR2 activation pathway.^[4]

Historical work

Purpurogallin, obtained by oxidation of pyrogallol, attracted attention for dyeing. Arthur George Perkin (son of William Henry Perkin, discoverer of the dye mauvine) reported early characterization including the formation of trimethyl ether and the triacetate..^[5]