Tannins

thumb|Representative chemical structure of a tannic acid, a type of tannin thumb|Tannin powder (mixture of compounds) thumb|A bottle of tannic acid solution in [[water ]]

species of plant

thumb|Catechu thumb|right|150 px|Bottle of catechu thumb|left|200 px|Catechu

Thiolysis is a reaction with a thiol (R-SH) that cleaves one compound into two. Thiolysis involves the addition of coenzyme A to one of the products. This reaction is similar to hydrolysis, which involves water instead of a thiol. This reaction is seen in β-oxidation of fatty acids. The depolymerisation of condensed tannins with the use of benzyl mercaptan as nucleophile is also called thiolysis.

species of plant

Phlobaphenes (or phlobaphens) are reddish, alcohol-soluble and water-insoluble phenolic substances. They can be extracted from plants, or be the result from treatment of tannin extracts with mineral acids (tanner's red). The name phlobaphen come from the Greek roots φλoιὀς (phloios) meaning bark and βαφή (baphe) meaning dye.