Constictic acid is a chemical compound of the

depsidone Depsidones (+ " depside" + "one") are chemical compounds that are sometimes found as secondary metabolites in lichens. They are esters that are both depsides and cyclic ethers. An example is norstictic acid Norstictic acid is a depsidone produ ...

class. It was first isolated in 1968 from

lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...

of the genus ''

Usnea ''Usnea'' is a genus of fruticose lichens in the large family Parmeliaceae. The genus, which currently contains roughly 130 species, was established by Michel Adanson in 1763. Species in the genus grow like leafless mini-shrubs or tassels anch ...

''. It has since been found in many other lichen genera including ''

Menegazzia ''Menegazzia'' is a genus of lichenized fungi containing roughly 70 accepted species.Galloway, D.J. (2007). Flora of New Zealand - ''Menegazzia'' http://floraseries.landcareresearch.co.nz/pages/index.aspx The group is sometimes referred to as the ...

'', '' Crespoa'', and ''

Xanthoparmelia ''Xanthoparmelia'' (commonly known as green rock shields or rock-shield lichens) is a genus of foliose lichens in the family Parmeliaceae.Field Guide to California Lichens, Stephen Sharnoff, Yale University Press, 2014, This genus of lichen i ...

''.

References

Lactones Benzaldehydes Heterocyclic compounds with 4 rings Hydroxyarenes Methoxy compounds Benzodioxepines Lichen products Oxygen heterocycles {{Ether-stub