Two previously unknown red alkaloid pigments, mycenarubin A (1), and a dimer thereof, mycenarubin B (6), have been isolated from fruiting bodies of Mycena rosea and the structures of these pyrroloquinoline alkaloids have been established by 2D NMR and ESI-MS methods. Their absolute configurations were determined by comparison of their CD spectra with the CD spectrum of a synthetic model com-

Two previously unknown blue alkaloid pigments, sanguinone A (1) and sanguinone B (2), and one new red indoloquinone alkaloid, sanguinolentaquinone (3), have been isolated from Mycena sanguinolenta fruiting bodies. In addition, decarboxydehydrosanguinone A (4) was identified as an oxidative decarboxylation artifact of 1. The structures of these alkaloids have been established by 2D NMR and ESIMS methods. The absolute configurations of 1 and 2 were determined by comparison of their CD spectra with the CD spectrum of mycenarubin A (5), which we isolated recently from fruiting bodies of the mushroom Mycena rosea. The sanguinones are structurally related not only to the mycenarubins A (5) and B but also to a large number of marine alkaloids such as the discorhabdins.

Four so far unknown red alkaloid pigments, haematopodin B (1) and the mycenarubins D (3), E (5) and F (6), were isolated from fruiting bodies of Mycena haematopus. The structures of these pyrroloquinoline alkaloids were established by 2D NMR spectroscopic and MS (ESI) methods. Their absolute configurations were determined by comparison of their CD spectra with that of haematopodin (2) or mycenarubin A (4).

The native precursors E/Z‐1a to E/Z‐1e and 2a–2e of the antifungally active benzoxepines E/Z‐1 and 2 have been isolated from intact fruiting bodies of Mycena galopus. These precursors turned out to be fatty acid esters of the benzoxepines (pterulones) E/Z‐1 and 2. Metabolic profiling of ethyl acetate extracts from intact fruiting bodies, from the latex and from mechanically wounded fruiting bodies revealed that the known antifungally active benzoxepines E/Z‐1 and the previously unknown benzoxepines 2 are only present in injured fruiting bodies. Intact fruiting bodies and the latex, however, exclusively contain the corresponding ester derivatives E/Z‐1a to E/Z‐1e and 2a–2e. Unlike the antifungally active benzoxepines E/Z‐1 and 2, the esters E/Z‐1a to E/Z‐1e present in intact fruiting bodies turned out to be inactive. Upon injury the inactive esters E/Z‐1a to E/Z‐1e are cleaved by a putative esterase, and the bioactive benzoxepines E/Z‐1 and 2 are released, suggesting a wound‐activated defence mechanism of M. galopus against yeasts and parasitic fungi. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Three new chlorinated phenols have been isolated from mycelial cultures of the mushroom Mycena alcalina. Their structures were determined by mass spectrometry and 1D and 2D NMR experiments. Addition of bromide to the medium resulted in the production of the corresponding brominated phenols. In addition, small amounts of the nonhalogenated precursor were also isolated, indicating that the halogenated metabolites are generated by a regioselectively operating halogenase.