Two new tetracyclic cytochalasans, flavichalasines A and B (1 and 2), three new pentacyclic cytochalasans, flavichalasines C–E (3–5), and eight new tricyclic cytochalasans, flavichalasines F–M (6–13), together with eight known analogues (14–21), were isolated from the solid culture of Aspergillus flavipes. Structures of these new compounds were elucidated on the basis of extensive spectroscopic analyses including 1D, 2D NMR and HRESIMS data. Their absolute configurations were determined by comparison of their experimental ECD with either computed ECD or experimental ECD spectrum of known compound. The structure and absolute configuration of 2 were further determined by X-ray crystallographic diffraction. Flavichalasine A (1) represents the first example of cytochalasan with a terminal double bond at the macrocyclic ring and flavichalasine E (5) is the only cytochalasan with an α-oriented oxygen-bridge in D ring. These new compounds were evaluated for their cytotoxic activities against seven human cancer cell lines, of which, 6 and 14 displayed moderate inhibitory activities against tested cell lines. In addition, compounds 6 and 14 induced apoptosis of HL60 cells by activation of caspase-3 and degradation of PARP.

Chemical investigation on the methanol extract of Chaetomium globosum TW1-1, a fungus isolated from the common pillbug (Armadillidium vulgare), has resulted in the isolation of nine new highly oxygenated cytochalasan alkaloids, armochaetoglobins S–Z (1 and 3–9) and 7-O-acetylarmochaetoglobin S (2), together with eight structurally related known analogues (10–17). Their structures and absolute configurations were elucidated by spectroscopic analyses. Among them, compound 2 presents to be the first member of chaetoglobosin family with an acetyl group, and compounds 3 represents the first chaetoglobosin characterized by an 2′,3′-epoxy-indole moiety. The discovery of these new compounds revealed the largely untapped chemical diversity of cytochalasans and enriched their chemical research. Compounds 1–9 were evaluated for their cytotoxic activities against five human cancer cell lines, and compounds 8 and 9 exhibited significant cytotoxic activities with IC50 values ranging from 10.45 to 30.42 μM.

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Seven prenylated benzoylphloroglucinol derivatives, named sampbenzophenones A–G (1–7), together with two known analogues (8 and 9), were isolated from the aerial parts of Hypericum sampsonii.

Two new azaphilone derivatives, chaephilones A (1) and B (2), were isolated from the fungus Chaetomium globosum, together with four structurally related analogs 3 - 6. The structures of 1 and 2 were elucidated by comprehensive spectroscopic analyses including HR-ESI-MS and NMR. The known compounds were identified as chaetomugilin Q (3), chaetomugilin D (4), 11-epichaetomugilin A (5), and chaetomugilin S (6) by comparing their NMR data and optical rotation values with those reported. Compound 2 represents the first example of azaphilone with an open furan ring. Compounds 1 and 2 were evaluated for cytotoxic activities against five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW480) by the MTS method.