Records of Natural Products
A scientific open access journal in the field of natural products.
Records of Natural ProductsA scientific open access journal in the field of natural products.
5,6-dihydroxypyranoflavone, a New Flavonoid with an Oxidized Prenyl Group from Dietary Plant Citrus hystrix
Citrus hystrix has been widely used as beverages, traditional condiments and folk medicines. In this study, 5,6-dihydroxypyranoflavone (1), a new flavonoid with an oxidized prenyl group, and three known phenols (2-4), were separated from the leaves of this plant. Their structures were elucidated using comprehensive spectroscopic data including 1D NMR, 2D NMR and mass spectral analysis. Additionally, 5,6-dihydroxypyranoflavone (1) exhibited moderate antioxidant effect against DPPH and ABTS free radicals with IC50 values of 18.28 ± 0.36 and 12.46 ± 0.82 μM, respectively. The results suggested that the dietary plant Citrus hystrix could be considered as a potential source of natural antioxidants.DOI http://doi.org/10.25135/rnp.423.2309.2904 Keywords Citrus hystrix dietary plant flavonoid antioxidant effect Available online: November 09, 2023 DETAILS DOWNLOAD PDF © ACG Publications. All rights reserved.
Structurally Diverse Terpenoids from the Resins of Populus euphratica
Phytochemical analysis of Populus euphratica resins has resulted in the isolation and identification of two undescribed terpenoids, including a new triterpene (1), a new sesquiterpene (2), and nine additional terpenoid (3-11) compounds. The structures of these novel compounds were determined using HR-ESI-MS and NMR (1D and 2D) spectroscopic analyses, combined with ECD calculations. The inhibitory activity of these terpenoids against α-glucosidase was also evaluated, and the results revealed that none of the compounds exhibited significant α-glucosidase inhibitory activity at a concentration of 50 μM. Only compound 1 displayed weak inhibitory activity (1.84 ± 8.96%) compared to the positive control.DOI http://doi.org/10.25135/rnp.424.2306.2806 Keywords Populus euphratica resins sesquiterpenoids triterpenoids Available online: November 09, 2023 DETAILS DOWNLOAD PDF © ACG Publications. All rights reserved.
A New Ergosterol-Type Steroid Isolated from the Nicotiana tabacum-Derived Endophytic Fungus Aspergillus sp. TE-65L
Chemical study on the fungal strain Aspergillus sp. TE-65L, which was previously isolated from cultivated tobacco (Nicotiana tabacum L.), led to the production of four steroids including a new ergosterol-type steroid, namely aspergosterol A (1). Their chemical structures were established by detailed spectroscopic analysis of 1D/2D NMR and HRESIMS data. Compound 1 was found to possess anti-phytopathogenic activities against Alternaria alternate, Botrytis cinerea, and Fusarium oxysporum, with MIC values of 4, 8, and 16 μg/mL.DOI http://doi.org/10.25135/rnp.420.2309.2909 Keywords Aspergillus sp. endophytic fungus secondary metabolite steroid antifungal activity Available online: November 04, 2023 DETAILS DOWNLOAD PDF © ACG Publications. All rights reserved.
A New Chromanone Derivative from Calophyllum inophyllum Resin and Its Antibacterial Activity
A new chromanone derivative, calophylloidic acid B (2), was isolated from Calophyllum inophyllum resin in Lombok, Indonesia. The structure of the new compound was elucidated as a structural isomer of calophylloidic acid A (1), which we had previously isolated from Indonesian C. inophyllum resin. It exhibited potent antibacterial activity against Staphylococcus aureus and Escherichia coli.DOI http://doi.org/10.25135/rnp.421.2308.2890 Keywords chromanone Calophyllum inophyllum calophylloidic acid Indonesia antibacterial activity Available online: October 26, 2023 DETAILS DOWNLOAD PDF © ACG Publications. All rights reserved.