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. The dehydrated tergallic acid C-glucoside and tergallic acid O-glucoside can be characterised in the acorns of Quercus macrocarpa. Dehydrated tergallic-C-glucoside (m/z 613) can be found in the cork from Quercus suber.
