Thelephoric acid

Polyporic acid (3), the above cited terphenylquinone occurring in several species of basidiomycetes, has also been found in lichens of the Sticta genus [19]. Also thelephoric acid (82, see Section 3.2), widely distributed within Thelephoraceae, has been found in lichens of Lobaria genus [3], From the lichen Relicina connivens (Parmelia butleri) the butlerins A-F (51 - 56) were isolated [72, 73], These polyporic acid-related metabolites have not yet been found in fungi. 

The leuco peracetate of thelephoric acid (85) has been isolated from Boletopsis leucomelaena [69], The leuco permethyl ether of thelephoric acid (86) was obtained in minute amounts from mycelial mat of Pulcherricium caeruleum (Corticium caeruleum), a basidiomycete characterized by an indigo blue colour of its hymenial surface, and its... 

Among the early synthetic works, we wish to mention here the synthesis of polyporic acid (3) [115] and thelephoric acid (82) [78]. As summarised in Scheme 3a, several terphenylquinones have been synthesized with moderate yields starting from 2,5-dichlorobenzoquinone by arylation with V-nitrosoacetanilides or diazonium salts and subsequent alkaline hydrolysis. This method allowed preparation of symmetrical and unsymmetrical terphenylquinones, this latters with low yields. 

Absinthin, the active principle of wormwood, Artemisia absinthium L. (Compositae), is a dimeric guaianolide containing two lactone rings and two hydroxy groups per molecule.162 Thelephoric acid (76b), isolated from fungi of several Thelephora species, has been synthesized by oxidative condensation of two molecules of sodium 3,4-dimethoxy-phenoxide with one of chloranil in the presence of hydrobromic acid.162a... 

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