Pulvinic acid derivatives

Hydroxylated pulvinic acids are responsible for the yellow and red colours of most boletes. They also cause the characteristic blueing of the flesh which occurs when the fruit bodies of many species are cut or bruised. Because the distribution of the hydroxylated pulvinic acids such as variegatic acid (73) and xerocomic acid (72) is restricted to the order Boletales, their isolation from Gomphidius 608), Omphalotus 128, 397, 584), Hygrophoropsis 91, 126, 127, 198), Coniophora 86, 

121) provides strong evidence for the inclusion of these genera in Boletales. 

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The tropical fungus Scleroderma sinnamariense has afforded methyl 2, 5 -dichloro-4,4 -di-0-methylatromentate (2196) (1979), and the related pulvinic acid derivative methyl 3, 5,-dichloro-4.4 -di-0-methylatromentate (2197) was isolated from the fruiting body of a Scleroderma sp. ( poison puff ball ) (1980). A New Zealand Chamonixia pachydermis has yielded pachydermin (2198) (1981). 

Screening pigments Pulvinic dilactone Pulvinic acid derivative 1672 1405 >246 290 367 431 422... 

C (decomp.). A pulvinic acid derivative from the mushroom Gomphidius glutinosus (Basidio-mycetes). Together with xerocomic acid G. is responsible for the yellow color of the stem base. 

Table 8. Occurrence of Common Pulvinic Acid Derivatives ...

Besides atromentic acid, xerocomic acid, and variegatic acid a number of less common pulvinic acid derivatives have been isolated from Basidiomycetes (Table 11). 

A unique pulvinic acid derivative, methyl bovinate (98), which contains an extra carbon atom in the form of the carbonyl group of an additional 5-lactone ring has been isolated by Besl et al. from cultures of Suillus bovinus 99). Its structure followed from the spectroscopic data, particularly the proton coupled C-n.m.r. spectrum. 

Scheme 14. Regiospecific syntheses of pulvinic acid derivatives (108)...

Xerocomic acid exhibits moderate antibiotic activity against several bacteria 533, but compare 76). In recent years numerous pulvinic acid derivatives have been synthesised, and many have been shown to possess useful anti-inflammatory properties 710). 

The isolation of pulvinic acid derivatives from a member of the Sclerodermataceae points to a close taxonomic relationship between these gastroid fungi and the boletes (286). 

Gill, M., and D.A. Lally A Naphthalenoid Pulvinic Acid Derivative from the Fungus Pisolithus tinctorius. Phytochem. 24, 1351 (1985). 

Mosbach, K. On the Biosynthesis of Lichen Substances 2. The Pulvinic Acid Derivative Vulpinic Acid. Biochem. Biophys. Res. Commun. 17, 363 (1964). 

Mass spectrometry is another useful tool for the identification and structural elucidation of lichen substances. Tlje principles of the method are given in a review by Lehmann and Schulten (1976). The mass spectra (MS) of numerous depsides, depsidones, depsones, dibenzofuranes and diphenylbutadienes have been discussed by Huneck et al. (1968a). In the same year, Letcher (1968) published the MS of some pulvinic acid derivatives. Martinez and Mestres (1972) recorded the MS of depsidones derived from norstictic acid, and Holland and... 

Edwards, R. L., and M. Gill Constituents of the Higher Fungi. Part XIII. 2-Aryl-3-methoxymaleic Anhydrides from Pulvinic Acid Derivatives. A Convenient Method for Determination of Structure of Fungal and Lichen Pulvinic Acid Derivatives. J. Chem. Soc. (London) 1534(1973). 

Secondary Products of the Shikimic Acid Pathway Terphenylquinones and Pulvinic Acid Derivates... 

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