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.
Two new coumarins 7-O-(6-O-(5-O-3,4,5-tri-methoxycinnamate-β-d-apiofuranosyl-β-d-glucopyranosyl)-6-methoxy coumarin (1) and 7-O-(6-O-(4-(2-hydroxy-1-hydroxymethyl-ethoxy)-3-methoxy-cinnamyl)-β-d-glucopyranosyl)-6-methoxy coumarin (2), along with 10 known metabolites, were isolated from the bark of Streblus indicus, their structures were identified by comparison of experimental and published spectroscopic data. (S)-marmesinin (6) and scoparone (7) exhibited moderate antimicrobial activity in vitro against Staphylococcus aureus strain with the MIC values of 62.5 and 125.0 μg/mL, respectively. Betulinic acid showed inhibitory activity in vitro against MCF-7 cell with IC50 value of 9.5 ± 0.1 μM.
Two new triterpenoid glucosides, Heritiera A (1) and Heritiera B (2), and six known triterpenoid analogs (3–8) were isolated from Heritiera littoralis Dryand. Their structures were identified by comprehensive spectroscopic analyses and comparisons with the literature. The anti-inflammatory activity of the isolates from H. littoralis was evaluated using a lipopolysaccharide (LPS) stimulated RAW 264.7 cells model. The result showed that four triterpenoids exhibited potent anti-inflammatory activity. Among these compounds, compound 2 substantially inhibits the release of nitric oxide (NO) with an IC50 value of 10.33 μM. The triterpenoids from H. littoralis could be used as potential candidates for the development of new anti-inflammatory agents.
Seeking a supramolecular chiral system induced by trace chiral molecules instead of traditional complex and expensive chiral ligands to achieve high yield or ee value conversion of the products is of great significance in asymmetric synthesis but still remains a challenge. Herein, two types of double helical supramolecular chiral systems, (M)-Helix and (P)-Helix, with opposite chiral optics were constructed in situ using tyrosine-functionalized pillar[5]arene as inducers. These systems exhibit chiroptical stability and enable remarkable chirality amplification from 7 mol% chiral seeds. When applied to intermolecular olefin cyano-trifluoromethylation, (M)-Helix exhibits remarkable catalytic efficiency (yield up to 89%), whereas (P)-Helix achieves higher enantioselectivity (ee up to 84%). This research will provide new ideas for supramolecular chiral catalysts in organic asymmetric catalysis applications.
Six new triterpenoids, heritieras C–H (1–6), along with thirteen known triterpenoids (7–19), were isolated from the leaves of Heritiera littoralis. Their structures were identified by spectroscopic analysis, including 1D and 2D nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass spectrometry (HRESIMS), and by comparison with the literature. Anti-inflammatory activity of the isolates was evaluated using the lipopolysaccharide (LPS) stimulated RAW 264.7 cell model. Among the isolated triterpenoid, compounds 1, 12, 16, 17, and 18 demonstrated inhibitory activity against nitric oxide (NO) release, in which compound 18 exhibited the best activity with an IC50 value of 18.13 μM. The potential anti-inflammatory mechanism was investigated using molecular docking. The triterpenoids from H. littoralis could be served as potential candidates for the development of new anti-inflammatory agents.