Cytoglobosins A-G (1-7), seven new cytochalasan derivatives, along with two structurally related known compounds, isochaetoglobosin D (8) and chaetoglobosin F(ex) (9), were isolated and identified from the cultures of Chaetomium globosum QEN-14, an endophytic fungus derived from the marine green alga Ulva pertusa. The structures of the new natural products as well as their relative configurations were elucidated on the basis of 1D and 2D NMR spectra (COSY, HSQC, HMBC, and NOESY) and HRESIMS data. Cytoglobosins C and D (3 and 4) displayed cytotoxic activity against the A-549 tumor cell line.

Bioassay-guided fractionation of the culture extract of Aspergillus wentii EN-48, an endophytic fungus isolated from an unidentified marine brown algal species of the genus Sargassum, led to the isolation of three new tetranorlabdane diterpenoids, asperolides A-C (1-3), and five related derivatives (4-8). The structures of these compounds were established on the basis of spectroscopic interpretation, and compound 1 was confirmed by X-ray crystallographic analysis. The absolute configuration of 1 was determined by application of the modified Mosher's method. An X-ray structure for wentilactone B (6) is also reported. Compounds 1-8 were evaluated for cytotoxic and antibacterial activities.

Six new 4-phenyl-3,4-dihydroquinolone derivatives (1-6) along with the related aflaquinolone A (7) were isolated and identified from the cultures of Aspergillus nidulans MA-143, an endophytic fungus obtained from the fresh leaves of the marine mangrove plant Rhizophora stylosa. Their structures including absolute configurations were determined by spectroscopic analysis and electronic circular dichroism experiments, and the structure of compound 1 was confirmed by single-crystal X-ray crystallographic analysis. In bioscreening experiments, none of the isolated compounds showed potent antibacterial or cytotoxic activity. However, compounds 2, 3, and 7 exhibited lethality against brine shrimp (Artemia salina), with LD50 values of 7.1, 4.5, and 5.5 μM, respectively.