Dehydrohexahydroxydiphenic acid is a group found in dehydro

ellagitannin image:Castalagin.svg, 130px, Castalagin is a representative ellagitannin, characterized by coupled gallic acid substituents The ellagitannins are a diverse class of hydrolyzable tannins, a type of polyphenol formed primarily from the oxidative link ...

s. It is formed from

hexahydroxydiphenic acid Hexahydroxydiphenic acid is an organic compound with the formula HO)3C6HCO2Hsub>2. It is the oxidatively coupled derivative of gallic acid It is a white solid, although samples are typically brown owing to oxidation. Occurrence left, 142px, ...

(HHDP) through oxidation of the plant hydrolysable tannins.Correlation of oxidative transformations of hydrolyzable tannins and plant evolution. Takashi Yoshida and Tsutomu Hatano, Phytochemistry, November 2000, Volume 55, Issue 6, Pages 513–529, It is found in ellagitannins such as euphorbin A,

geraniin Geraniin is a dehydroellagitannin found in geraniums. It is found for instance in ''Geranium thunbergii'', which is one of the most popular folk medicines and also an official antidiarrheic drug in Japan. It can also be found in the rind of ''Nephe ...

or mallotusinic acid. In

, it is forming an equilibrium mixture of six-membered hemi-ketal and five-membered hemi-ketal forms.

References

Ellagitannins Dicarboxylic acids Heterocyclic compounds with 3 rings Oxygen heterocycles {{aromatic-stub