Basidiomycetes triterpenoids

C31H52O, Mr 440.75, cryst., mp. 158-159°C, [a]o -r66° (CHCI3). Biosynthetic precursor of numerous tetracyclic triterpenoids in fungi. Widely distributed in imperfect fungi, yeasts, basidiomycetes, and other fungi. 

Russula pigments. The yellow, red, and violet colors of russula mushrooms (Russula, Basidiomycetes) are caused by polar compounds, some of which exhibit intense fluorescence under UV light and are associated with the riboflavin- and pteridine metabolisms ( russupteridines). Russula flavida is an exception, its fruit bodies have an orange-yellow layer consisting of lipophilic triterpenoids of the russulaflavidin type. Ut. Z. Pilzkd. 39, 45 (1973) (review) Zechmeister 51, 210-215. 

S. A C30H4SO7, Mr 518.69, needles, mp. 145-146°C, [a]o +78.1° (CHCI3). Cytotoxic triterpenoids from the fruit bodies of the toadstool Tricholoma saponaceum (Basidiomycetes). The fungus also contains the 10-de-oxy derivative S. B C30H44O6, Mr 502.69, cryst., mp. 134-136°C, [aJu +17.9° (CHjClj)), as well as the (75)-7- and 3/5-hydroxy derivative S. C and D., respectively. The unusual S. system is probably formed bio-genetically by attack of a famesyl cation on a molecule of famesyl diphosphate. 

Tanaka N, Kitamura A, Mizushina Y, Sugawara F, Sakaguehi K (1998) Fomitellic acids, triterpenoid inhibitors of eukaryotic DNA polymerases from a basidiomycete, Fomitella fraxinea. JNat Prod 61(2) 193-197... 

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