Orsellinic acid, more specifically ''o''-orsellinic acid, is a
phenolic acid
Phenolic acids or phenolcarboxylic acids are types of aromatic acid compounds. Included in that class are substances containing a phenolic ring and an organic carboxylic acid function (C6-C1 skeleton). Two important naturally occurring types of ph ...
. It is of importance in the biochemistry of
lichens, from which it can be extracted. It is a common subunit of
depsides.
Chemistry
It can be prepared by the oxidation of
orsellaldehyde.
This is also produced when everninic acid and
ramalic acid is boiled with
barium hydroxide
Barium hydroxide is a chemical compound with the chemical formula Ba(OH)2. The monohydrate (''x'' = 1), known as baryta or baryta-water, is one of the principal compounds of barium. This white granular monohydrate is the usual commercial form.
...
. It forms colorless crystals in the form of needles which on rapid heating melt with decomposition in the neighborhood of 175 °C.
[Sep 22, 2021: this citation to J Chromatog 511 needs to be revised because that paper makes no reference to crystals of orsellinic acid nor its melting point. In fact, the text never specifically mentions orsellinic acid: it simply appears in Tables I, II & III.]
References
{{Phenolic acid
Dihydroxybenzoic acids
Salicylic acids
Alkyl-substituted benzenes