Chemistry & Biodiversity最新文献

Three new alkaloids (1–3), together with three known alkaloids (4–6), were isolated from the seeds of Orychophragmus violaceus. Their structures were elucidated by spectroscopic data analysis and ECD calculations. All compounds were assessed to evaluate their ferroptosis inhibition activity. Notably, compound 3 specifically inhibited erastin-induced ferroptosis in human intestinal epithelial cells (HIEC-6). Moreover, compound 3 significantly decreased the accumulation of reactive oxygen species (ROS), Fe²⁺, and lipid peroxide (LPO)-induced by erastin, and promoted the production of glutathione (GSH). This study provides fresh insights into the phytochemistry and pharmacological potential of O. violaceus.

One new phenylethanoid glycoside, named bungaside A (1), along with six known phenylethanoid glycosides (2–7), were isolated from the dried aerial parts of Clerodendrum bungei Steud. Their structures were elucidated from extensive spectroscopic analysis and hydrolysis. All the isolates were evaluated for their anti-tumor effects against H460, A549, and HepG2 cancer cell lines. Compound 7 showed moderate activity against all cell lines, with the half-maximal inhibitory concentration (IC₅₀) values ranging from 2.25 to 13.13 µM. Meanwhile, compounds 3 and 6 displayed weak activities on A549 with the IC₅₀ values of 11.61 ± 1.38 and 16.68 ± 1.16 µM. Compounds 3 and 6 displayed moderate activities on H460 with the IC₅₀ values of 5.10 ± 0.12 and 7.23 ± 0.65 µM, respectively. Besides, the preliminary structure-activities relationship showed that the skeleton of phenylethanoid glycosides containing a monosaccharide may have a stronger anticancer effect than their corresponding disaccharides, and the increase in the methylation of the hydroxyl group on the aromatic ring is also an important reason decrease in activity.

Quinazolinone derivatives have emerged as promising scaffolds in medicinal chemistry due to their broad spectrum of biological activities, including anticancer potential. Incorporation of triazole rings through click chemistry has further boosted the pharmacological relevance of such compounds, due to the triazole's stability, bioisosterism, and ability to engage in key interactions with biological targets. Motivated by these properties, a library of 24 triazolylmethyl-dihydroquinazolinyl benzoate (TDB) derivatives (7a–x) was synthesized using a click chemistry strategy, starting from anthranilamide and phthalic anhydride. The structures of the synthesized compounds were established through IR, ¹H NMR, ¹³C NMR, and HRMS spectral analysis. The anticancer potential of all derivatives was evaluated by using SRB assay, with compounds 7j and 7q displaying notable activity, with GI₅₀ values of 22 and 48 µg/mL, respectively. In addition, compounds 7a, 7e, 7f, 7l, 7u, 7v, and 7x displayed moderate activity, with GI₅₀ values ranging from 58 to 77 µg/mL. In addition, molecular docking studies were performed using poly(ADP-ribose) polymerase-1 as the target enzyme, and the results confirmed that the TDB derivatives exhibited strong binding affinity. Furthermore, molecular dynamics simulations were conducted to evaluate the stability of the docked complexes, specifically for compounds 7j and 7q, which confirmed that the TDB derivatives formed stable interactions with poly(ADP-ribose) polymerase-1.

The shell of Euryale ferox Salisb., rich in polyphenols, has antitumor potential. We isolated and identified polyphenols from the shell and evaluated their in vitro antitumor activity. Compounds were extracted with 70% ethanol under ultrasound and purified by fractional extraction and silica gel chromatography, yielding three substances. Liquid chromatography–mass spectrometry (LC-MS) and nuclear magnetic resonance confirmed the three compounds as ellagic acid, corilagin, and geraniin. High-performance LC quantification showed corilagin and geraniin concentrations of 66.23 and 58.41 mg/g. In vitro experiments on cells showed the ethanol extract had strong inhibitory effects on cell proliferation (IC₅₀: 68.56 µg/mL for HeLa, 78.09 µg/mL for A2780), and cell proliferation, migration, and invasion were regulated by the three compounds, exhibiting time- and dose-dependent characteristics. Corilagin showed the strongest inhibitory effect on HeLa cell proliferation (74.61% at 48 h) and A2780 cell invasion (69.86%). Geraniin inhibited HeLa cell invasion (63.33%) and A2780 cell invasion (61.64%). This study determined the chemical structures of polyphenolic compounds from Euryale ferox Salisb. shell and their impact on tumor cell proliferation, migration, and invasion, offering evidence for developing antitumor drugs and insights for modernizing traditional Chinese medicinal resources.

Psidium guajava L. is traditionally used for gastrointestinal issues, along with its use in lowering blood glucose. The present study evaluates the phytochemical composition, in vitro antioxidant potential, and antidiabetic properties of P. guajava L. hydro alcoholic extract (PGHE). TPC and TFC were quantified from PGHE. LC–ESI–QTOF–MS/MS and HPTLC were used for metabolite profiling. In vitro antioxidant, enzyme inhibition assays, and in silico molecular interactions were investigated for PGHE. The yield of extract was 6.16%. It exhibited high phenolic (147.2 ± 0.98 mg GAE/g) and flavonoid content (70 ± 1.67 mg QUE/g). HRLC–ESI–QTOF–MS/MS profiling tentatively identified 555 metabolites, with some bioactive compounds, that is, myricetin, quercetin, ellagic acid, and gallic acid. In vitro antioxidant assays showed potent radical scavenging activity, although lower than the standard antioxidant ascorbic acid. Enzyme inhibition assays revealed PGHE's α-glucosidase and α-amylase inhibition with IC₅₀ of 53.32 ± 0.25 and 79.28 ± 1.1 µg/mL, respectively. HPTLC confirmed the presence of gallic acid (0.028%), quercetin (0.093%), and ellagic acid (0.047%) with R_f values 0.592, 0.745, and 0.503. Molecular docking studies against α-amylase showed that ellagic acid had the highest binding affinity (−7.6 kcal/mol), better than the standard drug acarbose. The study links chemical diversity with functional efficacy and molecular interaction, offering a detailed in vitro and in silico validation of guava's glucose-lowering potential.

Natural products and their intricate framework always offer an unexplored source of chemotypes for any drug discovery. It is identified that >70% of the drugs were discovered directly from the natural sources or their direct analogs. Boswellic acids (BA) are one of such structurally diverse bioactive components that are isolated from the resin of the Boswellia genus. This resin is used for multiple ailments in indigenous medicine, especially in Indian Ayurveda and the Chinese medicine system. However, its complex structure and low bioavailability limit its applications in therapeutic use. Modifying BA (an abundant molecule from nature) semi-synthetically can improve biological and pharmacokinetic properties tremendously. During the past 35 years (1990–2025), numerous semi-synthetic modifications of BA have been established. The synthesized derivatives of BA possess novel molecular mechanisms against infectious and non-infectious diseases, making them valuable candidates for drug development. Based on the chemical/ biological importance, the review is presented, which covers the molecular scaffolds and pharmacological activities of BAs for various infectious and non-infectious diseases. Further, the structure-activity relationship provides a valuable addition to the drug discovery program.

Cancer and multidrug-resistant (MDR) bacterial infections are pressing global health concerns that demand continuous studies on new bioactive compounds. With a view to create new bioactives, the present study reports on the design and synthesis of novel fatty acid derivatives containing oxadiazole moiety and isoniazid in a molecular entity. The structures of the synthesized compounds were confirmed through nuclear magnetic resonance (NMR), infrared (IR) and mass spectrometry. Anticancer screening revealed that compounds 7b and 7e demonstrated notable cytotoxic activity, particularly against the B16-F10 cell line. Compound 7b exhibited the most potent activity with an IC₅₀ of 7.3 ± 0.8 µM in cancer cells and 18.4 ± 0.2 µM in normal cells, indicating a promising selectivity profile. The synthesized derivatives also displayed moderate antibacterial and antifungal effects in preliminary screening. Computational evaluations supported their drug-like physicochemical properties and favourable pharmacokinetics, whereas Toxicity Prediction by Computer Assisted Technology (TOPKAT) (a robust quantitative structure–toxicity relationship [QSTR]-based toxicity prediction tool) indicated promising safety profiles across multiple endpoints, such as mutagenicity and carcinogenicity. Together, these findings highlight these isoniazid–oxadiazole–fatty acid hybrids as promising dual-acting therapeutic candidates, warranting further development.

Eighteen lindenane sesquiterpenoid dimers, including three previously undescribed hetero- or homo-dimers (1–3), were isolated from the whole plant of Sarcandra glabra. Their structures were elucidated by High-resolution electrospray ionization mass spectrometry, one- and two-dimensional nuclear magnetic resonance, quantum chemical calculations, and electronic circular dichroism calculations. Notably, compound 1 is a rare hetero-dimer formed by [4 + 2] cycloaddition of a eudesmane and a lindenane sesquiterpene, via C-15−C-9′, C-6−C-8′, and C-11−C-7′ linkages. Compound 2 features a unique epoxide structural motif. All compounds were evaluated for their inhibitory effect on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in BV-2 cells. The inhibitory effects of all isolates on LPS-induced NO production in BV-2 cells were evaluated. Thirteen compounds, excluding 3, 5, 13, 15, and 16, exhibited IC₅₀ values ranging from 0.15 to 6.29 µM. Furthermore, compound 1 dose-dependently inhibited the release of NO in BV-2 cells by suppressing the expression of induced NO synthase, cyclooxygenase-2, and MYD88 proteins.

Three pairs of undescribed enantiomeric γ-pyrone derivatives placidenes G–I (1–3), together with two new congeners placidene J (4)/isoplacidene J (5) and two known compounds 6 and 7, were isolated from the marine mollusk Placida dendritica. Compounds 1a/1b–3a/3b were further separated by chiral-phase high-performance liquid chromatography. The structures were elucidated by comprehensive spectroscopic analysis, high-resolution electrospray ionization mass spectrometry, time-dependent density functional theory/electronic circular dichroism calculation, and X-ray diffraction analysis. In bioassays, compounds 1–5 exhibited moderate nitric oxide inhibition from 28.2% to 51.9% on RAW264.7 inflammatory cells at 20 µM without notable cytotoxicity.