Tergallic acid
Trimers of gallic acid
From Wikipedia, the free encyclopedia
Tergallic acids are trimers of gallic acid, often found naturally in the form of glycosides. Tergallic acid O- or C-glucosides that can be found in acorns of several Quercus (oak) species.[1] The dehydrated tergallic acid C-glucoside and tergallic acid O-glucoside can be characterised in the acorns of Quercus macrocarpa.[2] Dehydrated tergallic-C-glucoside (m/z 613) can be found in the cork from Quercus suber.[3]
Tergallic acid glucosides can also be found in Terminalia chebula.[4]
Tergallic acid dilactone can be found in Rhynchosia volubilis seeds.[5]
The chemical formula is not the same as given by Kinjo et al.[5] (molecule with an ether link between the ellagic and gallic acid residues) or by Cantos,[1] Chapman[2] and Fernandes et al.[3] (molecule with a carbon-carbon link). Cantos, Fernandes and Chapman called the molecule with an ether link valoneic acid dilactone while Kinjo and Shuaibu et al.[6] called the molecule with a carbon-carbon link flavogallonic acid dilactone.
