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A pair of enantiomers and a pair of 2,3-dihydro-1H-indene epimers, rac-indidene A (rac-1), indidenes B and C (2, 3); four new coumarin glucosides (4-7); and four known coumarin glucosides (8-11) were isolated from the bark of Streblus indicus (Bur.) Corner. The structures of 1-11 were defined by physical data analyses, including MS, NMR, and single-crystal X-ray diffraction. The absolute configurations of the 2,3-dihydro-1H-indene derivatives were defined via experimental and calculated ECD data. rac-Indidene A and indidenes B and C showed inhibitory activity against A549 and MCF-7 tumor cells with IC values in the range of 2.2 ± 0.1 to 7.2 ± 0.9 μM.

Cyclocarya paliurus is commonly used for the prevention and treatment of hypertension, diabetes, and inflammation in South China. Although research on the anti-inflammatory effects of C. paliurus leaves has been reported, no active anti-inflammatory compounds have been identified. In the present study, RAW 264.7 cells were used to establish a bioactivity-guided identification model to verify the inhibitory effects of C. paliurus leaves on inflammation and identify the anti-inflammatory constituents. The active fraction was isolated to yield 18 dammarane triterpenoid saponins, including 11 new 3,4-seco-dammarane triterpenoid saponins (1–11), the structures of which were identified on the basis of analyses of nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) and comparison with literature data. Compounds 7, 8, 10, and 11 showed strong inhibition on nitric oxide (NO) productions, with IC50 values ranging from 8.23 to 11.23 μM. These four compounds significantly decreased the secretion of tumor necrosis factor-alpha (TNF-α), prostaglandin E2 (PGE2), and interleukin 6 (IL-6) in lipopolysaccharide-activated RAW 264.7 cells. Furthermore, compound 7 decreased the expression of the proteins cyclooxygenase-2 (COX-2), inducible nitric-oxide synthase (iNOS), and nuclear factor kappa-B (NF-κB/p65). In addition, the structure–activity relationships of the isolates were investigated. The results suggest that 3,4-seco-dammarane triterpenoid saponins may be used as potential anti-inflammatory drugs and warrant further investigation.

Four undescribed compounds, guhypoxylonols A (1), B (2), C (3), and D (4), were isolated from the mangrove endophytic fungus Aspergillus sp. GXNU-Y45, together with seven previously reported metabolites. The structures of 1–4 were elucidated based on analysis of HRESIMS and NMR spectroscopic data. The absolute configurations of the stereogenic carbons in 1–3 were established through a combination of spectroscopic data and electronic circular dichroism (ECD). Compounds 1–11 were evaluated for their anti-inflammatory activity. Compounds 1, 3, 4, and 6 showed an inhibitory activity against the production of nitric oxide (NO), with the IC50 values of 14.42 ± 0.11, 18.03 ± 0.14, 16.66 ± 0.21, and 21.05 ± 0.13 μM, respectively.

The plant Sophora tonkinensis, possessed a range of active compounds, was traditionally used in the medicine of Chinese minorities. Endophytic fungi were isolated from this plant, of which the fungus Diaporthe sp. GDG-118 was fermented and extracted with methanol. The extract was screened by antifungal and antibacterial assays leading to the discovery of two new 21-acetoxycytochalasins (1-2) and five known cytochalasins (3-7). These two new compounds were elucidated by spectroscopic analyses, and further their absolute configurations were determined by the X-ray of compound 3 and comparing their experimental CD spectra. The antibacterial and antifungal effects of these compounds were evaluated. Compound 2 showed moderate inhibitory activity against Bacillus anthraci and Escherichia coli with MIC value of 12.5 μg/mL, and 7 showed strong antifungal activity against Alternaria oleracea, Pestalotiopsis theae and Colletotrichum capsici with MIC values of 3.125 μg/mL, 1.56 μg/mL and 1.56 μg/mL, respectively.

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