Records of Natural Products

Phytochemical investigation of the roots of Euphorbia fischeriana led to the isolation of a novel acetophenone derivative, named Euphebranone F (1), along with three known  acetophenone analogs (2–4). The structure of the new compound, featuring a C-C linkage between the C-9 of the acetophenone unit and C-8′ of  the phenylpropanoid moiety, was  elucidated by extensive NMR and HRESIMS analysis, and its absolute configuration was determined by ECD calculations. Cytotoxic activity screening against human gastric cancer cell lines (MKN-45 and AGS) revealed that only compound 2 exhibited moderate antiproliferative activity against MKN-45 cells.

A new quassinoid, named vilmorinine G (1), along with two known congeners (2 and 3), has been isolated from the root bark of Ailanthus altissima (Mill.) Swingle. The structure of 1 was elucidated through spectroscopic evidence in NMR, HR-ESI-MS, and ECD. The absolute configuration of 1 was further confirmed by X-ray crystallography.

A rare isoflavone mannoside, mannodaidzein (1), along with three known isoflavones (2–4), was isolated from the culture broth of an actinomycete Saccharothrix sp.JS2. Their chemical structures were determined by 1D/2D NMR and HR(ESI)MS data analyses. Among them, only compound 2 exhibited weak anti-proliferative activity against HT1080 cells at 100 µM. The structure-activity relationship analysis revealed that modification of the C-4' hydroxyl group adversely affected cytotoxicity. Mannodaidzein (1) represents the first mannoside of flavone.

The current study was designed to investigate the chemical composition, antioxidant, enzyme inhibitory, and cytotoxic activities of Scorzonera coriacea A.Duran & Aksoy. Both organs were rich in total phenolic content, with the highest content recorded from the 70% EtOH (48.41 mg GAE/g) and aqueous (47.11 mg GAE/g) extracts of the roots. All aerial parts extracts accumulated higher total flavonoid content than their respective roots extracts, with the highest amount found in their EtOH extract (36.44 mg RE/g). Chemical analysis revealed the presence of 86 compounds belonging to organic acids, phenolic acids, flavonoids, coumarins, anthocyanins, terpenes, saponins, and fatty acids and their derivatives, with the aerial parts accumulating the highest number. The roots displayed the strongest antiradical and ion-reducing capacities. EtOH extract of both organs recorded the highest acetylcholinesterase activity (2.77 and 3.02 mg GALAE/g; p≥0.05), while that of the root showed the best butyrylcholinesterase activity (3.49 mg GALAE/g) and that of the aerial parts the best tyrosinase inhibitory (59.07 mg KAE/g). EtOAc of the root exhibited the best cytotoxicity towards the HepG2 cell line (cell viability = 29.30%), but was also toxic towards HEK293 cells (cell viability = 11.72%). In silico screening supported these findings by identifying multiple strong ligand–protein interactions. Molecular dynamics simulations further confirmed the structural stability of selected complexes. In silico profiling docked 26 phytochemicals against 14 therapeutic targets, generating 364 complexes, of which 62% showed ΔG ≤ −7.0 kcal·mol⁻¹. Binding energies ranged from −1.4 to −10.7 kcal·mol⁻¹, with PD-1–Eriodictyol-7-O-neohesperidoside the best. For metabolic enzymes, Eriodictyol-7-O-neohesperidoside yielded the top α-amylase score and Diosmetin-7-O-glucoside the top α-glucosidase score, while several flavonoids bound AChE/BChE strongly; in contrast, tyrosinase displayed poor affinity overall. 100-ns MD simulations on five top complexes indicated stable behavior for C1 and C4, whereas C2/C3/C5 showed loosening interactions over time. These findings showed that S. coriacea could be a promising source of bioactive compounds with potential therapeutic applications.