Natural Product Research最新文献

A new ocotillol-type ginsenoside, named pseudoginsenoside F₁₂ (1), was isolated from American ginseng berry, whose structure was elucidated as 6-O-[α-L-2,3-epoxy-rhamnopyranosyl-(1-2)-β-D-glucopyranosyl]-dammar-20S,24R-epoxy-3β, 6α,12β,25-tetraol. In addition, the known alkaloids β-carboline-1-carboxylic acid (2) and anoectochine (3) were isolated for the first time from the Araliaceae family. The new compound 1 was evaluated for cytotoxicity against MDA-MB-231 breast cancer cell line.

A new anthraquinone, altermodinacid A (1), and five known derivatives, pachybasic acid (2), emodic acid (3), emodin (4), phomarin (5), and 1,7-dihydroxy-3-methylanthracene-9,10-dione (6), were discovered from a halotolerant fungus Alternaria sp. X112 isolated from a marine fish Gadus macrocephalus. Their structures were determined by analysing MS and NMR data. The cytotoxic effect, antiagricultural pathogens activity, antibacterial activity and quorum sensing inhibitory potential of new compound 1 were evaluated.

Chemical investigation of corn silk resulted in the isolation of nine secondary metabolites, including a new ent-kaurane diterpenoid, zeamaysditerpene A (1) and eight known compounds, stigmaydene A (2), stigmaydene J (3), stigmaydene L (4), stigmane D (5), demethyltorosaflavone D (6), chrysoeriol 6-C-β-boivinopyranosyl-7-O-β-D-glucopyranoside (7), deoxypodophyllotoxin (8), and α-peltatin glucoside (9). Their structures were elucidated using a combination of spectroscopic methods, including 1D and 2D NMR and HRESIQTOF mass spectra. The absolute configuration of 1 was deduced by applying electronic circular dichroism (ECD) calculation method. Among the isolates, only 6 displayed significant inhibition against PTP1B activity in a dose-dependent manner, with an IC₅₀ value of 10.7 ± 0.1 µM. Furthermore, molecular docking simulation was carried out to explore the action perspective of 6 inside the enzyme PTP1B. This finding suggests that 6 might be a potential lead for the development of a new anti-diabetic agent.

Phytochemical investigation of Chrysanthemum indicum L. yielded two new quinolinone glycoalkaloids named as Chrysanthemumsides A-B (1-2). The structures of the new compounds were elucidated by analysis of their 1D- and 2D-NMR, HRESIMS and ECD calculations. Compounds 1-4 were evaluated for antimicrobial activity against the Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans, and the data showed that compound 2 had significant antimicrobial effects (MIC 3.9 to 7.8 μg/mL).

The phytochemical investigation of the aqueous methanolic extract of the aerial parts of Dioscorea preussii, led to the isolation of a new chalcone preussiate (1) along with 10 other compounds including xanthomicrol (2), cholestan-3-one (3), arjunolic acid (4), tormentic acid (5), ursolic acid (6), betulin (7), lupeol (8), p-hydroxybenzoic acid (9), isovanillin (10) and vanillic acid (11), being reported for the first time from this plant. Their structures were established by spectroscopic techniques including 2D NMR spectroscopy. All the isolates were subjected to the biological screening but only showed antioxidant and urease inhibitory properties. The compounds 1,8 and 11 displayed the most potent urease inhibitory properties with IC₅₀ values, 22.4_, 33.3 and 35.7 µM, respectively, while 3 was moderately active. The compound 11 showed potent antioxidant activity among all the tested isolates with an IC₅₀ value of 45.3 µM.

A successful column chromatography of a CHCl₃/MeOH crude extract of Dendronephthya spp. soft coral led to the isolation of two new aromatic A-ring steroids (1-2), together with three known compounds (3-5). Both 1 and 2 are 19-norsteroids. The chemical structures were elucidated based on extensive 1D, 2D NMR, and EIMS analyses. In cytotoxic bioassays, compounds 1-5 were tested against three cancer cell lines: MCF-7, NCI-1299, and HepG2, with IC₅₀ in the ranges of 22.1-85.4, 26.9-88.7, and 25.9-93.7 μM, respectively. Compounds 1, 2, and 5 showed moderate degrees of inhibition against Escherichia coli and Pseudomonas sp. at 100 and 150 µg/mL, while exhibiting weak inhibition against Bacillus cereus and Staphylococcus aureus at 150 µg/mL.

Embelin is one of the primary compounds present in the Embelia ribes fruit. Embelin has a broader pharmacological activity such as Anti-inflammatory, anti-bacterial, antioxidant, and many more. The ultimate aim of the study is to ensure the impact of reduced embelin in the management of Alzheimer's disease. Embelin was isolated and modified by the reduction method, and the Modified Embelin derivative (MED) 3-Undecylcyclohexa-2,5-diene-1,2,4,5-tetraol was analysed through FT-IR, NMR, and Mass Spectroscopic techniques. MED was docked against acetylcholinesterase (AChE) amyloid beta (Aβ) receptors PDB ID: 1EVE & 1B68, respectively. The docking scores remain similar to that of positive standards galantamine and Donepezil.

The chemical composition of the essential oil from the fruits and leaves of Litsea cubeba (Lour.) Pers. (Lauraceae) growing wild in Baoshan region, Yunnan Province of China was investigated for the first time in 5.36% and 2.16% (w/w) yields, respectively, when analysed by GC and GC/MS. Ten and 25 components were identified in the fruit and leaf oils which constituted 99.15% and 99.4% of the oils. Of the fruit oil, the major components were neral (36.51%), geranial (44.23%), and citronella (8.77%). The major components of the leaf oil were linalool (67.37%), limonene (6.37%), β-bisabolene (6.03%), neral (5.86%), and caryophyllene oxide (3.20%). The analysis of the essential oil obtained from Baoshan revealed a significant abundance of citral and linalool in the fruits and leaves, respectively. This was the first Litsea species to exhibit β-bisabolene as the principal constituent.

A new sesquiterpene glycoside, ligulariatinside A (1), along with nine known compounds, dibutyl phthalate (2), 1-O-(9Z,12Z-octadecadienoyl) glycerol (3), bis (2-ethylhexyl) phthalate (4), 4-hydroxy-3-methoxyphenylpropanol (5), dihydrosyringenin (6), caffeic acid (7), 6β-hydroxy-7(11)-eremophilen-12,8α-olide (8), together with the mixture of 6β,8β-dihydroxyeremophil-7(11)-en-12,8α-olide (9) and 6β,8α-dihydroxy-eremophil-7(11)-en-12,8β-olide (10) were isolated from roots of L. veitchiana. Structures of these compounds were elucidated by comprehensive analyses of HRESIMS, 1D NMR, and 2D NMR spectroscopic data. Compounds 2 and 4 are not likely natural compounds but contaminants. All isolated compounds were tested for antibacterial activity. Compounds 1, 5, 6, together with the mixture of 9 and 10, showed mild activity against Vibrio anguillarum, with MIC values of 50, 50, 100, and 200 μg/mL, while compound 7 showed moderate activity against Vibrio anguillarum, with a MIC value of 25 μg/mL.

The chemical investigation of the aerial part of Abrus canescens led to isolation of a new triterpenoid glycoside named Canescensoside (1) and four known compounds including longispinogenin-3-O-β-D-glucuronopyranoside (2), β-sitosterol-3-O-β-D-glucoside (3), apigenin-7-O-β-D-glucopyranoside (4) and apigenin-7-O-[α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranoside] (5). Structures of compounds were assigned by interpretation of their spectral data, mainly 1D and 2D NMR, HRESIMS, and by comparison with the reported data. The MeOH extract, EtOAc and n-BuOH fractions as well as isolated compounds were tested for their antibacterial activities against four bacteria strains among which, two Gram-negative (Pseudomonas aeruginosa ATCC 76110 and Escherichia coli ATCC 8739) and two Gram-positive (Enterococcus faecalis ATCC 29212 and Staphylococcus aureus ATCC 25923) bacteria using the broth microdilution method. The MeOH extract and EtOAc fraction exhibited significant activities (MIC values ranging from 128 to 512 μg/mL) against all the tested bacteria. Compounds 2 and 3 showed the lowest MIC values of 55.47 and 50.40 µM, respectively.