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Two lanostane dimers, ganoweberianones A (1) and B (2), together with seven previously undescribed lanostanes, ganoweberianic acids A–G (3–9), and three known compounds (10–12), were isolated from the artificially cultivated fruiting bodies of the basidiomycete Ganoderma weberianum. Ganoweberianone A (1) exhibited significant antimalarial activity against Plasmodium falciparumK1 (multidrug-resistant strain) with an IC50value of 0.050 μM. A method for semisynthesis of 1by condensation of the corresponding lanostane monomers and acid-catalyzed intramolecular transesterification was demonstrated.

The wood-rot basidiomycete Ganoderma colossushas been chemically investigated. Comparative analyses of the natural fruiting body, artificially cultivated fruiting bodies, and mycelial cultures resulted in the isolation, in total, of 13 new highly modified lanostanes, ganocolossusins A–H (1–8) and ganodermalactones T–X (9–13), together with 23 known compounds (14–36). There were significant overlaps of the same compounds among the three different states of the fungal materials. Ganocolossusin D (4) displayed the most potent antimalarial activity against Plasmodium falciparumK1 (multi-drug-resistant strain) with an IC50value of 2.4 μM, while it was noncytotoxic to Vero cells at 50 μg/mL.

Fourteen new compounds, oudemansins 1–4, oudemansinols 5–7, favolasins 8–10, favolasinin (12), polyketides 13–15, and (R,E)-2,4-dimethyl-5-phenyl-4-pentene-2,3-diol (16), together with nine known compounds were isolated from the basidiomycete fungus Favolaschiasp. BCC 18686. Two new compounds, favolasin E (11) and 9-oxostrobilurin E (17), were isolated from the closely related organism Favolaschia caloceraBCC 36684 along with nine β-methoxyacrylate-type derivatives. Compounds in the class of oudemansins and strobilurins exhibited moderate to strong antimalarial activity with relatively low cytotoxicity against Vero cells (African green monkey kidney fibroblasts). Potent antimalarial activity was demonstrated for 9-methoxystrobilurins G, K, and E (IC50values 0.061, 0.089, and 0.14 μM, respectively). The structure–activity relationships (SAR) for antimalarial activity is proposed on the basis of the activity of the new and several known β-methoxyacrylate derivatives in combination with the data from previously isolated compounds. Furthermore, several compounds showed specific cytotoxicity against NCI-187 cells (human small-cell lung cancer), although the SAR was different from that for antimalarial activity.

In a continuation of our research into antitubercular lanostane triterpenoids from submerged cultures of Ganodermaspecies, three strains, Ganoderma orbiformeBCC 22325, Ganodermasp. BCC 60695, and Ganoderma australeBCC 22314, have been investigated. Fourteen new lanostane triterpenoids, together with 35 known compounds, were isolated. Antitubercular activities of these mycelium-associated Ganodermalanostanoids against Mycobacterium tuberculosisH37Ra were evaluated. Taken together with the assay data of previously isolated compounds, structure–activity relationships of the antitubercular activity are proposed. Most importantly, 3β- and 15α-acetoxy groups were shown to be critical for antimycobacterial activity. The most potent compound was (24E)-3β,15α-diacetoxylanosta-7,9(11),24-trien-26-oic acid (35).

Metabolites 1and 2, isolated from cultures of the basidiomycete Resupinatussp. BCC84615, collected in a tropical forest in northeastern Thailand, showed weak antibiotic activity against Bacillus subtilisand Staphylococcus aureusand cytotoxicity against cancer cell lines. Their planar structures were elucidated by high-resolution electrospray ionization mass spectrometry and NMR spectroscopy as clavilactone J, known from the basidiomycete Ampulloclitocybe clavipes, and its new 1,4-benzoquinone derivative. A detailed analysis of the ROESY correlations in 1confirmed the recent revision of the relative configuration of clavilactone J. However, specific rotation and Cotton effects observed by electronic circular dichroism were contrary to those of the clavilactones; thus, we assigned a rare antipodal absolute configuration.

Sixteen new lanostane triterpenoids (1–16), together with 26 known compounds (17–42), were isolated from cultures of the basidiomycete Ganodermasp. BCC 16642. Antitubercular activities of these Ganodermalanostanoids against Mycobacterium tuberculosisH37Ra were evaluated, and structure–activity relationships are proposed.