Poronia punctata

Punctatin A (34), also known as antibiotic M 95464, is an unusual metabolite which has been isolated from the dung fungus Poronia punctata. An enantiospecific synthesis of (34) has now been described which features, amongst other things, use of the Norrish type II photoreaction viz (32)- -(33) to elaborate the cyclobutane ring... 

Gloer, j. B. and S. M. Truckenbrod, Interference competition among coprophilous fungi Production of (-t-)-isoepoxydon by Poronia punctata, Appl. Environ. Microbiol., 54, 861-864... 

Fermentation of (-)-p-caryophyllene (451) with D. gossypina afforded 14 different metabolites (453-457j), among which 14-hydroxy-5,6-epoxide (454) and the corresponding acid (455) were the major metabolites. Compound 457j is structurally very rare and found in Poronia punctata. The main reaction path is epoxidation at C5, C6 as mentioned earlier and selective hydroxylation at C4 (Abraham et ah, 1990) (Figure 20.132). 

Among the family of terpenes, the 9,4-bicyclic terpenes, such as caryophyllene or punctaporonin B, have also received scant attention, except caryophyllene, synthesized by Corey. Punctaporonin B was isolated from extracts of the drug fungus Poronia punctata. Kende et al. described the first total synthesis of racemic punctaporonin B by an efficient and potentially general strategy for the construction of such fused 9,4 systems. The construction of the key intermediate 327 from readily accessible cyclobutanone 326... 

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