Boletopsis leucomelaena

The structure of the 4,3 ,4 -trihydroxy derivative of polyporic acid was assigned in 1942 by Akagi to the brown pigment leucomelone (47) isolated from the black edible mushroom Polyporus leucomelas (.Boletopsis leucomelaena) collected in Japan [68], From the same fungus, Akagi obtained also a colourless compound named protoleucomelone (48), established as the leuco-peracetate of 47. 

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... 

CigHioO, Mr 338.27, brown plates or powder, mp. 320 °C (decomp.). Component of the fruit bodies of Boletopsis leucomelaena (=Polyporus leucomelas, Basidiomycetes). C. is identical to leucomelone for which the erroneous structure of a 2-(3,4-dihydroxy-phenyl)-3,5-dihydroxy-6-(4-hydroxyphenyl)-p-ben-zoquinone was previously assumed. In B. leucomelaena and the fruit bodies of various Anthracophyllum species C. occurs in free form or in the form of leuco compounds that are partially or completely acetylated. These compounds are responsible for the green color reaction of fruit bodies on treatment with alkalis. Poly-acetylated leucocycloleucomelones are effective inhibitors of 5-lipoxygenase. 

Cycloleucomelone (14) Anthracophyllum archeri, A. discolor [artefact ] 385), Boletopsis leucomelaena = Polyporus leucomelas) [Teucomelone ] (7, 386), Paxillus atrotomentosus 365)... 

In 1942 Akagi isolated a terphenylquinone, Teucomelone , from fruit bodies of the edible black mushroom Boletopsis leucomelaena (= Polyporus leucomelas) for which he proposed the formula (19) (7). The quinone formed a peracetyl derivative, m.p. 226-227° C (9), and was accompanied in the fungus by its leuco-peracetate, protoleucomelone ... 

Recently, the leuco-peracetate (54) of thelephoric acid has been isolated from sporophores of Boletopsis leucomelaena (386). The leuco-permethyl ether (67) of thelephoric acid occurs in minute amounts in the indigo blue coloured mycelial mats of Pulcherricium caeruleum ( = Corticium caeruleum) and its structure has been established by an X-ray crystal analysis (581, 711). The chemical nature of the blue pigment from this organism is a matter of dispute. Briggs et al. (135) obtained blue solutions (A, ax = extraction of the mycelium... 

Jagers, E(lisabeth), E. Hillen-Maske, and W. Steglich Inhaltsstoffe von Boletopsis leucomelaena (Basidiomycetes) Klarung der chemischen Natur von Leucome-lon und Protoleucomelon . Z. Naturforsch., in press. 

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