Chemistry & Biodiversity最新文献

Recent investigations have identified prenylated isoflavonoids as major constituents of Erythrina addisoniae, yet their anti-neuroinflammatory potential remains unexplored. Through bioassay-guided isolation, two new prenylated isoflavonoids (1 and 2), along with nine known compounds (3–11), were characterized using spectroscopic methods. All isolates were tested for inhibitory effects on nitric oxide (NO) production in BV-2 microglial cells. Compounds 1, 6, 7, and 10 significantly reduced NO levels, with compounds 1 and 10 showing the strongest activity (IC₅₀ values of 3.57 ± 1.22 and 0.69 ± 0.18 µM, respectively). Western blot analysis confirmed the downregulation of inducible NO synthase protein, and molecular docking analysis revealed that compound 10 interacts with nuclear factor kappa-light-chain-enhancer of activated B cells. These results highlight prenylated isoflavonoids from E. addisoniae as potential anti-neuroinflammatory agents.

As a traditional Chinese medicine, Centella asiatica (CA) contains diverse chemical constituents, which serve as the basis for its broad-spectrum pharmacological activities. This study aimed to investigate the therapeutic effects of CA on glycolipid metabolism disorders in ob/ob mice and conduct a systematic qualitative and quantitative analysis of the chemical composition of CA. The results demonstrated that CA extract effectively ameliorated glucose intolerance and insulin resistance, decreased blood lipid levels, and alleviated hepatic steatosis in ob/ob mice. A total of 39 chemical constituents were identified in the CA extract. To facilitate the quality evaluation of CA, we established a rapid and precise method for the simultaneous quantification of eight target compounds—asiaticoside, asiaticoside B, madecassoside, asiatic acid, madecassic acid, stachyose, kaempferol glucuronide, and quercetin-3-O-glucuronide in CA medicinal materials. Notably, this study represents the first quantitative analysis of stachyose, kaempferol glucuronide, and quercetin-3-O-glucuronide in CA, thereby complementing and expanding the existing framework for its quality control.

A convenient approach to the synthesis of quaternary phosphonium salts, bearing a diterpenoid fragment is proposed. This highly regioselective synthesis is based on the reaction of quinopimaric and dehydroquinopimaric acids with P─H-phosphonium salts. The structures of obtained quaternary phosphonium salts based on quinopimaric and dehydroquinopimaric acid were confirmed by NMR and IR spectroscopy, mass spectrometry, and XRD. Compounds possess both antibacterial activity and in vitro cytotoxicity against human cancer cell lines. Selectivity of cytotoxic action depends on substituents in the aromatic moieties of phosphonium salts. Also, phosphonium derivatives of quinopimaric acid, possessing a hydroxyvinyl fragment bound directly to the phosphorus atom, show a higher cytotoxicity than dehydroquinopimaric acid phosphonium derivatives. Highest cytotoxicity is for the phosphonium derivatives of quinopimaric acid, containing 4-methoxyphenyl substituents (IC₅₀ = 1.5–2.8 µM). Apoptosis test suggests that the cytotoxic mechanism involves a substantial contribution of the mitochondrial pathway of apoptosis.

Essential oils (EOs) are volatile aromatic compounds highly valued in cosmetics due to their multifunctional biological activity and long history of use. Because of their rich chemical composition and wide spectrum of action, EOs protect the skin, support regeneration, and serve as natural preservatives. Historically, plants rich in EOs were used to refresh and soothe the skin, and Cleopatra is often mentioned as an early example of their use. Today, EOs are extensively incorporated into cosmetics due to their antimicrobial, antioxidant, and regenerative properties. Their complex composition enables them to function both as natural preservatives and as active agents that promote skin health. Growing concerns over the safety of synthetic preservatives have driven consumers toward plant-based alternatives, increasing interest in EO-based formulations. Modern techniques such as nanoencapsulation and polymeric carrier systems are now used to enhance the stability, bioavailability, and safety of these oils, reducing potential skin irritation. However, challenges remain due to compositional variability, limited toxicological data, and regulatory complexity. Despite these issues, EOs continue to be regarded as promising eco-friendly ingredients for next-generation cosmetics. This review covers their chemical diversity, biological properties and potential as natural antiseptics compared with conventional synthetic agents, underlining recent advances made in their cosmetic applications.

Extracellular exo-β-(1,3)-glucanase is among the cell-wall enzymes that play important roles in cell-wall synthesis. Many antimicrobial agents act by targeting those specific enzymes to inhibit bacterial or fungal cell wall formation. In this context, we aimed to synthesize a novel series of N-substituted-2-[3-(methylsulfonyl)-2-oxoimidazolidine-1-carbonyl]hydrazine-1-carbothioamide derivatives (1–16). The structures of the synthesized compounds (1–16) were elucidated by using spectroscopic methods such as IR, ¹H NMR, ¹³C NMR, ¹³C APT NMR, and 2D NMR, as well as elemental analysis data. All thiosemicarbazide compounds (1–16) were screened for antimicrobial activity against seven bacteria (Staphylococcus aureus, MRSA, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Enterococcus faecalis) and three fungi (Candida albicans, Candida tropicalis, and Candida parapsilosis) strains. Among the compounds, 3 and 14 demonstrated the highest antibacterial activities against S. aureus with the MIC values in the range of 156.24–312.5 µg/mL. On the other hand, compound 9 showed the strongest antifungal activity in the series against all three fungi strains, with the MIC values in the range of 39.06–312.5 µg/mL. Furthermore, compound 9 was found to successfully bind to exo-β-(1,3)-glucanase using molecular docking and dynamics simulations run for 500 ns. The physicochemical, pharmacokinetic, and ADMET properties of compounds were also investigated and analyzed by in silico programs.

Artemisia vestita is a traditional Tibetan folk medicine. Bioactivity-guided fractionation revealed that the petroleum ether fraction of A. vestita possessed potent anti-complementary activity (CH₅₀: 0.016 ± 0.006 mg/mL), demonstrating therapeutic efficacy against H1N1-induced viral pneumonia in murine models. Subsequent phytochemical analysis of this bioactive extract using silica gel chromatography coupled with semi-preparative high-performance liquid chromatography yielded 14 compounds, including three new monoterpenes (1–3) and one coumarin (13) with relatively high abundance. Notably, studies on the activity of the isolated compounds revealed that the coumarin (scopoletin) exhibits dominant anti-complementary activity and provides significant protective effects against H1N1-induced viral pneumonia in mice. This study provides insights into the development and utilization of A. vestita and scopoletin.