Hypothamnolic acid

Hypothamnolic acid small rhombic crystals Imbricaric acid large needles Lecanoric acid thin curved needles Lecanoric acid prisms... 

Fig. 28. A Hiascic acid, GE. Bar 100 im. B Homosekikaic acid (from Cladonia ramulosa (With.) Laundon), oT. Bar lOOjLim. C Hypothamnolic acid (from Cladonia pseudostellata Asah.), GE. Bar 100 p.m. D Hypothamnolic acid, GE. Bar 10 pm.

The best known para-depsides are atranorin, baeomycesic acid, barbatic acid, chloroatranorin, diffractaic acid, squamatic acid and 4-(9-demethylbarbatic acid, while meta-depsides include decarboxythamnolic acid, haemathamnolic acid, hypothamnolic acid and thairmoUc acid. 

PD-,K+,C+ Cryptochlorophaeic acid, hiascic acid, hypothamnolic acid (K+ violet), merochlorophaeic acid, paludosic acid, ramalinolic acid, scrobiculin... 

The colored reaction products obtained in the C test are unstable and easily destroyed by an excess of the reagent. Hypothamnolic acid (albeit substituted at the position between the m-hydroxyls) gives a red color with C which disappears within seconds. The chemistry behind the Ctest has not been elucidated. Possibly a combination of chlorination and oxidation reactions leads to monomeric and/or dimeric quinonoid structures. Only one colored compound has been isolated from the reaction of orcinol with calcium hypochlorite the yellow tetrachlorodihydroorcinol (L. Gren and J. Santes-son, unpublished). 

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