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.