Records of Natural Products

Aconitaimine A, a new hetidine-type C20-diterpenoid alkaloid (1), and three known aconitine-type C19-diterpenoid alkaloids (2-4) were isolated from the roots of Aconitum taipeicum. The structures of all isolates were identified by spectroscopic methods and comparison with literature data. Compounds 1 and 2 showed inhibition of nitric oxide production in RAW 264.7 macrophages stimulated by lipopolysaccharide with IC50 values of 30.5 and 4.7 μM compared to positive control (dexamethasone, IC50 = 12.9 μM).

Filamentous fungi are very well known for producing a wide variety of secondary metabolites with important biological effects. In our study chemical exploration of the Nicotiana tabacum symbiotic fungus Aspergillus japonicus TE-739D led to the discovery of a new polyketide derivative, namely (3S,4E,6E,9S)-9-hydroxy-3,7-dimethyldeca-4,6-dienoic acid (1), along with three previously reported compounds 2−4. The structures of these compounds were elucidated by using HRESIMS, NMR spectroscopic analyses, and quantum chemical calculations. Compounds 3 and 4 showed strong antibacterial activity against four representative bacterial strains including two Gram-negative species (Agrobacterium tumefaciens and Xanthomonas oryzae) and two Gram-positive Bacillus species (B. cereus and B. subtilis), with MIC values range from 1 to 16 μg/mL, respectively.

This study involved the extraction, isolation, structural elucidation of a new analogue of zhepiresionol, as well as five lignans previously identified, from the plant Ailanthus altissima (Mill.) Swingle. The structural elucidation was accomplished through comprehensive analyses of various spectroscopic data, which included HRESIMS, UV, IR, and NMR, along with a comparison of ECD curves. At a concentration of 15 µM, Compound 1 showed the capacity to suppress IL-1β and IL-6 expression in RAW 264.7 cells that were Lipopolysaccharide-stimulated.

A new dammarane triterpenoid glycoside cyclocarioside Z14 (1) and four known compounds (2-5) were isolated from the dichloromethane extract of the leaves of Cyclocarya paliurus. The chemical structures were elucidated by the extensive spectroscopic data analysis of NMR, HR-ESI-MS, and acid hydrolysis. All isolated compounds were assayed on the cytotoxicity against seven human cancer cell lines. The compounds 1 and 3 showed moderate cytotoxicity against MCF-7 cells with an IC50 value of 29.51 μM and 33.88 μM.