Bird nest fungi

Cybullol (377), previously reported as a metabolite of Bird s Nest fungi (c/. Vol. 7, p. 95), and geosmin (379), a degradation product of cybullol and the fungal metabolite responsible for the earthy aroma of freshly ploughed soil, have been synthesized by the routes outlined in Schemes 36 and 37. ... 

Abscisic acid (ABA) (65), an important plant-growth regulator in higher plants, has been identified, for the first time, as an authentic metabolite of a fungus Cercospora rosicola). Further research on the constituents of bird s nest fungi cf. Vol. 7, p. 95 Vol. 8, p. 111) has established that the bicyclofarnesane lactones (66a—c) are produced by still cultures of Mycocalia reticulata Petch. An... 

Cycloaddition to a 1,3-cyclohexadiene. Racemic cybullol (4), a metabolite of bird s nest fungi cyathus bulleri), has been synthesized by the route shown in equation (I). -... 

The cyathins are a group of metabolites from the Bird s Nest fungi. Cyathatriol (83), which is related to cyathin A3, together with its mono- and di-acetates, has been isolated from Cyathus earlei. The labelling and coupling patterns produced in 11-O-acetylcyathatriol (85), when it is biosynthesized from [ C]2-... 

Ayer, W.A., and D.R. Taylor Metabolites of Bird s Nest Fungi 5. The Isolation of l-Hydroxy-6-methyl-8-hydroxymethylxanthone, a New Xanthone, from Cyathus intermedins. Synthesis via Photoenolisation. Canad. J. Chem. 54, 1703 (1976). 

Scheme 5 shows a possible biosynthetic pathway leading to the pterosins from famesyl pyrophosphate via humulene (411), protoillu-dane (412), illudane (414) or illudalane (413) as intermediates. Biogenet-ically related sesquiterpenes have been obtained as metabolites of basi-diomycetes (319, 320) and ascomycetes (321). Pterosin C (480), for example, is produced by one of the bird s nest fungi, Cyathus bulleri (322). 

Onychiol B (623) was isolated from rhizomes of Onychium japonicum (348). All known compounds with the cyathane skeleton except onychiol B (623) have been isolated from bird s nest fungi, Cyathus species (356). 

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