Four angucycline glycosides including three new compounds landomycin N (1), galtamycin C (2) and vineomycin D (3), and a known homologue saquayamycin B (4), along with two alkaloids 1-acetyl-β-carboline (5) and indole-3-acetic acid (6), were isolated from the fermentation broth of an intertidal sediments-derived Streptomyces sp. Their structures were established by IR, HR-ESI-MS, 1D and 2D NMR techniques. Among the isolated angucyclines, saquayamycin B (4) displayed potent cytotoxic activity against hepatoma carcinoma cells HepG-2, SMMC-7721 and plc-prf-5, with IC₅₀ values 0.135, 0.033 and 0.244 μM respectively, superior to doxorubicin. Saquayamycin B (4) also induced apoptosis in SMMC-7721 cells as detected by its morphological characteristics in 4′,6-diamidino-2-phenylindole (DAPI) staining experiment.

Three new sesquiterpenoids, isodauc-7(14)-en-6α,10β-diol (1), 10β-hydroxyisodauc-6-en-14-al (2), and (7S*)-opposit-4(15)-en-1β,7-diol (4), along with ten known compounds have been isolated from the aerial parts of Senecio argunensis. Their structures were established by means of detailed spectroscopic analysis including IR, HR-MS, and 1D NMR and 2D NMR data. The sesquiterpenoids were assayed against Escherichia coli, Staphylococcus aureus and Bacillus subtilis. Compounds 4 exhibited weak antibacterial activity against Escherichia coli and Bacillus subtilis.