Flavipucine and Brunnescin, Two Antibiotics from Cultures of the Mycophilic Fungus Cladobotryum rubrobrunnescens

Two antimicrobial metabolites were isolated from submerged cultures of Cladobotryum rubrobrunnescens, a mycophilic fungus growing on a Inocybe species. One of the compounds proved to be identical to flavipucine (2), an antibiotic previously isolated from Aspergillus flavipes (Casinovi et al., 1968) and from a Macrophoma species (Sassa T. and Onuma Y. (1983), Agric. Biol. Chem. 47, 1155-1157). The other metabolite, brunnescin (1), is a new tetrasubstituted furan derivative which exhibits antibacterial, antifungal and cytotoxic effects.