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Six angucyclines including three unreported compounds (1–3) were isolated from Streptomyces sp. XS-16 by overexpressing the native global regulator of SCrp (cyclic AMP receptor). The structures were characterized based on nuclear magnetic resonance (NMR) and spectrometry analysis and assisted by electronic circular dichroism (ECD) calculations. All compounds were tested for their antitumor and antimicrobial activities, and compound 1 showed different inhibitory activities against various tumor cell lines with IC50 values ranging from 0.32 to 5.33 μM.

Five new sesquiterpenoids, citreobenzofuran D–F (1–3) and phomenone A–B (4–5), along with one known compound, xylarenone A (6), were isolated from the culture of the mangrove-derived fungus Penicillium sp. HDN13-494. Their structures were deduced from extensive spectroscopic data, high-resolution electrospray ionization mass spectrometry (HRESIMS), and electronic circular dichroism (ECD) calculations. Furthermore, the absolute structures of 1 were determined by single-crystal X-ray diffraction analysis. Citreobenzofuran E–F (2–3) are eremophilane-type sesquiterpenoids with rare benzofuran frameworks, while phomenone A (4) contains a rare thiomethyl group, which is the first report of this kind of sesquiterpene with sulfur elements in the skeleton. All the compounds were tested for their antimicrobial and antitumor activity, and phomenone B (5) showed moderate activity against Bacillus subtilis, with an MIC value of 6.25 μM.

Four new anthraquinone derivatives, namely saliniquinones G−I (1–3) and heraclemycin E (4), were obtained from the Antarctic marine-derived actinomycete Nocardiopsis aegyptia HDN19-252, guided by the Global Natural Products Social (GNPS) molecular networking platform. Their structures, including absolute configurations, were elucidated by extensive NMR, MS, and ECD analyses. Compounds 1 and 2 showed promising inhibitory activity against six tested bacterial strains, including methicillin-resistant coagulase-negative staphylococci (MRCNS), with MIC values ranging from 3.1 to 12.5 μM.