Six new meroterpenoids, which have been named as stachybonoids A–F (1–3 and 5–7), and three known phenylspirodrimanes (4, 8 and 9) were isolated from the crinoid-derived fungus Stachybotrys chartarum 952. Their structures were established on the basis of extensive spectroscopic data (1D and 2D NMR, MS, and ECD), as well as the modified Mosher's method and single-crystal X-ray structural analysis. Compound 1 exhibited inhibitory activity against the replication of dengue virus. Compounds 4, 7, and 8 exhibited moderate anti-inflammatory activity by inhibiting the production of nitric oxide (NO) in RAW264.7 cells activated by lipopolysaccharide, with IC50 values of 27.2, 52.5, and 17.9 μM, respectively.
Trichobamide A (1), a novel pyrrocidine alkaloid with an unprecedented tetrahydro-5H-furo[2,3-b]pyrrol-5-one moiety, was isolated from the ascidian-derived fungus Trichobotrys effuse 4729. Trichobamide A (1) showed significant inhibition of the proliferation of two glioma cell lines, U251 and SNB19. It induced the up-regulation of P53 expression, which in turn induces the up-regulation of downstream pro-apoptotic gene expression and the down-regulation of anti-apoptotic gene expression.
1 October 2019 in European Journal of Medicinal Chemistry
Seven polyketides, including two new isochromanes, penisochromanes A and B (1 and 2), as well as five known compounds were obtained from an ascidian-derived fungus Penicillium sp. 4829. Their structures were identified by extensive spectroscopic analyses. The structures of compounds 1 and 3 were further determined by the X-ray crystallography. Compounds 1 and 2 were the first example of isochromane with three adjacent oxy substituents in natural source. Compound 4 exhibited selective activities against two Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis, with MIC values 6.25 and 12.5 μM, respectively.
Five new naphthalenones, two enantiomers (−)-1 and (+)-1 leptothalenone A, (−)-4,8-dihydroxy-7-(2-hydroxy-ethyl)-6-methoxy-3,4-dihydro-2H-naphthalen-1-one ((−)-2), (4S, 10R, 4’S)-leptotha-lenone B (5), (4R, 10S, 4’S)-leptothalenone B (6), and a new isocoumarine, 6-hydroxy-5,8-dimethoxy-3-methyl-1H-isochromen-1-one (4), along with two known compounds (+)-4,8-dihydroxy-7-(2-hydroxy-ethyl)-6-methoxy-3,4-dihydro-2H-naphthalen-1-one ((+)-2) and (+)-10-norparvulenone (3) were isolated from the marine-derived fungus Leptosphaerulina chartarum 3608. The structures of new compounds were elucidated by HR-ESIMS, NMR, and ECD analysis. All compounds were evaluated for cytotoxicity and anti-inflammatory activity. Compound 6 showed moderate anti-inflammatory activity by inhibiting the production of nitric oxide (NO) in lipopolysaccharide-stimulated RAW264.7 cells, with an IC50 value of 44.5 μM.