Structure Elucidation Research Articles

Amide Functionalized Novel Pyrrolo-pyrimidine Derivative as Anticancer Agents: Synthesis, Characterization and Molecular Docking Studies.

The development of new therapies targeting crucial kinases involved in cancer progression is a promising area of research. Pyrazolo pyrimidine derivatives have emerged as potential candidates for this purpose. This study aims to synthesize pyrazolo pyrimidine derivatives (5a-5r), evaluate their molecular docking against key kinases, and assess their anticancer activity. The synthesis involved a multi-step procedure starting with the cyclization of 6-amino-2- methylpyrimidin-4(3H)-one (1) to form 2-methyl-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-4-ol (2). This was followed by chlorination to yield 4-chloro-2-methyl-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidine (3) and nucleophilic substitution to produce 2-methyl-4,7-dihydro-3H-pyrrolo[2,3-d]pyrimidin-4-amine (4). The final derivatives (5a-5r) were synthesized through amide bond formation with various carboxylic acids using DCC and DMAP. Structural elucidation was confirmed via NMR, mass spectrometry, and HRMS. Molecular docking studies were conducted against Janus kinase 1 (JAK1), Janus kinase 2 (JAK2), and cyclin-dependent kinase 4 (CDK4). Anticancer activity was evaluated against MCF-7, SET-2, and HCT-116 cell lines. Structural elucidation confirmed the successful synthesis of the derivatives. Molecular docking studies revealed promising binding affinities for selected derivatives, particularly those with heterocyclic substitutions. Anticancer activity evaluation showed diverse potency profiles, with several derivatives demonstrating IC50 values comparable to the reference drug, doxorubicin. Derivatives featuring nitro and heterocyclic moieties exhibited significant anticancer activity. The synthesized pyrazolo pyrimidine derivatives showed potential as lead compounds for further development due to their promising binding affinities and significant anticancer activity, particularly those with nitro and heterocyclic moieties.

Systematic Characterisation of the Fragmentation of Flavonoids Using High-Resolution Accurate Mass Electrospray Tandem Mass Spectrometry

Flavonoids are a class of polyphenolic secondary metabolites found in plants. Due to their ubiquity in our daily dietary intake and their major anti-oxidative, anti-inflammatory and anti-mutagenic activities, they have been a major focus of wide-ranging research for the past two decades. Mass spectrometry combined with liquid chromatography is one of the most popular techniques for the analysis of flavonoids. In this study, high-resolution accurate mass electrospray tandem mass spectrometry was used to study 30 flavonoids in both positive and negative ionisation modes. From the data obtained, common losses were summarised and compiled. Dominating neutral losses were tabulated. The radical loss of CH3· was observed in flavonoids containing methoxy groups and three key diagnostic product ions were identified. These were m/z 153 (indicative of two OH groups on ring A) m/z 167 (indicative of one OH and one methoxy group on ring A) and m/z 151 (a flavanol, with no ketone oxygen but two OH groups on ring A). These will be useful in structural elucidation of unknown flavonoids and flavonoid metabolites. Energy breakdown graphs were utilised to distinguish between three pairs of structural isomers, and to help rationalise proposed fragmentation pathways. Lastly, a competition of loss of CH3· and methane was reported for rhamnetin and isorhamnetin in the negative ion mode for the first time. Proposed fragmentation pathways were given to rationalise the differences in peak intensities for this competitive process.

Structural Elucidation and Complete NMR Spectral Assignments of Monascus Monacolin Analogs.

One new monacolin analog, monacolin V (1), together with two new monacolin-like natural products, 6-hydroxyl monacolin P (2) and 3-keto monacolin S (3), were isolated from the ethyl acetate portion of red yeast rice ethanol extract. Their structures were identified by HRESIMS and NMR experiments, and the complete assignments of 1H and 13C NMR data for three compounds were obtained by the aid of HSQC, HMBC, 1H-1H COSY, and NOESY data. This is the first time that the NMR data of compounds 2 and 3 have been fully assigned.

Diastereomers of the Anticancer Peptide CIGB-300 with Altered β-Turn Structures

Abstract Purpose The next-generation anti-tumor drug peptide CIGB-300, developed by the Center for Genetic Engineering and Biotechnology (CIGB), targets casein kinase 2 (CK2) and its substrates, implicating significant therapeutic potential in cancer treatment. A key focus of this study was to compare CIGB-300 and a primary synthetic byproduct, CIGB-300iso, which shares the amino acid sequence with CIGB-300 but was proposed to differ due to racemization. Methods This study explores the synthesis, characterization, and structural elucidation of CIGB-300 and its isomer CIGB-300iso by a comprehensive NMR analysis of seven synthesized diastereomers including amino acid residues C15, H21, and C25. Results This study revealed that CIGB-300iso contains one D enantiomer at position H21. The structures of both isoforms derived from NMR constraints disclosed that the L and D enantiomers have an altered peptide supersecondary structure, with a β-turn type IV3 found in CIGB-300 and a type I β-turn in CIGB-300iso. Conclusion The configuration of H21 significantly impacts the peptide’s conformations, sidechain orientations and, potentially, its biological activity. These findings highlight the importance of enantiomerically pure peptides for the design and synthesis of drug peptides.

Bioassay-guided isolation and in Silico characterization of cytotoxic compounds from Hemimycale sp. Sponge targeting A549 lung cancer cells

Bioassay-guided fractionation approach led to identification of two novel compounds; (4-(hydroxymethyl)-3-methoxy-1H-pyrazol (1) and mycalene (2), alongside with four known metabolites; octadecane (3), hexatriacontane (4), 1-heneicosanol (5) and heptatriacontanoic acid (6) from the Red Sea marine sponge Hemimycale sp. The ethyl acetate fraction showed a noticeable cytotoxic activity against the lung cancer cell line (A549) with IC50 value of 75.54 µg/ mL. Structural elucidation was achieved using a combination of 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and high-resolution electrospray ionization-mass spectrometry (HR-ESI-MS). To elucidate the potential mechanism of action behind the cytotoxic effects against lung cancer, a multi-faceted approach combining in silico network pharmacology, experimental validation, and molecular docking studies were employed. Both compounds, designated as 1 and 2, demonstrated significant binding affinities to predicted target proteins, with docking scores of -4.789 and − 4.421 kcal/mol, respectively. These results lay the groundwork for further investigation into the therapeutic potential of these novel compounds from Hemimycale sp. as promising candidates for lung cancer treatment.

One-pot synthesis of tricyclic pyrano[3.2-c]chromene derivatives and their evaluation through in vitro immunomodulatory activity against T cells; Molecular docking investigations and ADME-Tox prediction studies

The aim of this work is the in vitro determination of the immunomodulation effect of pyrano[3,2-c]chromenes on the proliferation of T lymphocyts. These tricyclic heterocycles were prepared at room temperature via a one-pot, three-component condensation reaction involving 4-hydroxy-2H-chromen-2-one, aromatic aldehydes, and malononitrile, using morpholine as a catalyst in a 1:1 ethanol/water mixture. This multicomponent reaction affords the product in high yields, in accordance with the criteria of green chemistry. The structure elucidation was accomplished by spectral data, IR, NMR (1H, 13C, 2D). We determined the in vitro effects of 2-amino-4-(3-hydroxy-5-methoxyphenyl)-5-oxo-4H,5H-pyrano[3,2-c]chromene-3-carbonitrile (AC09) the 2-amino-5-oxo-4-(thiophen-2-yl)-4H,5H-pyrano[3,2-c]chromene-3-carbonitrile (AC11) derivatives, on the proliferative responses of human T lymphocyts cells, cytokine secretion and intracellular redox status. The study revealed that compounds AC09 and AC11 are efficient immunostimulants in a dose-dependent manner.Human lymphocytes were less sensitive to AC11 at high concentrations compared to the potency of AC09. Human lymphocyte IL-2, IFNγ and IL-4 secretions were significantly enhanced by those pyrano[3,2-c]chromenes derivatives in a dose-dependent manner. The levels of intracellular lymphocytes glutathione (GSH), were unaffected by AC09 and AC11 at any concentrations. AC09 and AC11 induce a significant increase in hydroperoxide and carbonyl protein contents at high concentrations. Conversely, a computational study using molecular modelling revealed that compounds AC09 and AC11 exhibit a strong affinity for the active site residues of Interferon-γ (IFN-γ; PDB ID: 6E3K) target. This is confirmed by the low score energy value and the formation of different types of interactions such as: hydrogen bonds, hydrophobic interactions, and van der Waals forces. Moreover, all Drug likeness's rules were validated, and no toxicity is presented by these compounds. Finally, in vitro studies, molecular docking techniques and ADME-T (Absorption, Distribution, Metabolism, Excretion and Toxicity) evaluations were successfully conducted, aiding in the identification of new IFN-γ target inhibitors. A comparative analysis /or studies was then carried out to highlight the complementary effects of the two approaches.

Unveiling industrial emissions in a large European river: Insights from data mining of high-frequency measurements

Despite the tremendous efforts to improve river water quality, chemical contamination remains a significant issue. Besides well-known contaminants, in recent years, pollutants of industrial origin received increasing attention because of the huge knowledge gap regarding their occurrence, fate and environmental risks. Moreover, such pollutants often exhibit high concentration fluctuations over time, which makes them less predictable and measurable with classical short-time campaigns.This study provides insights into the different sources of chemical contamination of the Rhine River based on temporal high-frequency LC-HRMS monitoring data from a single location. A newly developed prioritization strategy selected nearly 3000 substances as potentially major contaminants. A novel classification analysis based on temporal behavior identified 53% of these compounds (accounting for 62% of the time-integrated intensity recorded in the dataset) as originating from irregular emission sources. Irregular emissions can originate from industrial production cycles. After delimiting other potential irregular sources, we have strong evidence indicating that a considerable share of the irregular emissions likely comes from industrial activities. This finding is supported by the structural elucidation of sixteen irregularly emitted substances, for which the industrial origin was successfully confirmed. Those compounds include 3-chloro-5-(trifluoromethyl)pyridine-2-carboxylic acid and 4-(dimethylamino)-2,2-diphenylpentanenitrile. In addition, 40 other compounds exhibited temporal emission patterns similar to the sixteen industrial compounds, which strongly suggests a common contamination source. Finally, 100 top-ranking compounds were selected for further structural elucidation and emission reduction measures. The computational approach outlined within this study can be effectively applied in other large river catchments to identify unknown contaminants stemming from industrial sources.

Integration of MALDI glycotyping and NMR analysis to uncover an O-antigen substructure from pathogenic Escherichia coli O111

Escherichia coli O111 serotype is a critical pathogenic E. coli strain that causes severe, potentially fatal complications. Despite its reported variation, only one structure of the O-antigen polysaccharide from E. coli O111 has been reported. Here, a substructure of the O-antigen from E. coli O111 was characterized using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and NMR analysis. MALDI glycotyping revealed differing O-antigen repeating unit masses of Δm/z 787 and 828 in the E. coli strains and lipopolysaccharides from the O111 serogroup. This variation was caused by the replacement of the hexose residue with hexosamine in the repeating units, which was further confirmed by LIFT-TOF/TOF analysis. Structural elucidation of the O111 substructure by NMR analysis further demonstrated replacement of the hydroxyl group with an N-acetyl group on the terminal glucose residue of the O-antigen pentasaccharide repeating unit. To our knowledge, this study is the first to provide a detailed structural analysis of a new O-antigen substructure from the E. coli O111 serogroup.

The general glycan profiling of Dendrobium officinale and their protective effects on MIN6 cells via ERK signaling pathway

Based on structural elucidation of natural and hydrolyzed glycans, the general glycans profiling of D. officinale were unequivocally established for the first time as follows: [Display omitted] The results indicated that the structure of D. officinale glycans with low degree of polymerization (DP ≤ 22) was linear α-D-1,4-glucan, whereas the structure of glycans with high degree of polymerization (DP > 24) was linear acetylated 1,4-glucomannan. The content of acetyl groups and mannose to glucose (M/G) ratio increased with the degree of polymerization of D. officinale glycans. In addition, this study showed that natural D. officinale glycans protected pancreatic β-cell damage induced by glucotoxicity through the extracellular signal–regulated kinase (ERK)1/2 pathway.

Design, Characterization, and Bioactivity Evaluation of Novel Symmetrical N,N'-benzene-1,2-diylbis[1-(2-chloroquinolin-3-yl)methanimine] based metal complexes

This study presents the synthesis and characterization of two novel metal complexes derived from the symmetrical Schiff base N,N'-benzene-1,2-diylbis[1-(2-chloroquinolin-3-yl)methanimine] (OBCQ), coordinated with Nickel(II) (NiOBCQ) and Copper(II) (CuOBCQ). The structural elucidation of these complexes was achieved through a comprehensive suite of analytical techniques, including elemental analysis, UV-visible spectroscopy, mass spectrometry, infrared spectroscopy, magnetic susceptibility, conductivity measurements, and thermal analysis. The data confirm that both NiOBCQ and CuOBCQ adopt octahedral geometries, formulated as [Ni(OBCQ)(H₂O)₂(Cl)₂] and [Cu(OBCQ)(H₂O)₂(Cl)₂], respectively. Density Functional Theory (DFT) calculations were employed to validate the molecular structures and explore the quantum chemical parameters of OBCQ and its metal complexes. Additionally, in vitro assessments of anti-inflammatory and antioxidant activities revealed enhanced bioactivity for the metal complexes compared to the free OBCQ ligand. Molecular docking studies against key proteins (5IKT for Human Cyclooxygenase-2 and 5IJT for Human Peroxiredoxin 2) highlighted strong binding affinities and molecular interactions, suggesting that OBCQ and its metal complexes hold significant promise as novel therapeutic agents with multifaceted biological activities.

Early Days in the Hunt Laboratory at UVA, 1969-1980

Arriving at the University of Virginia in the autumn of 1969, Donald Hunt began his 50+ year career in academics with the study of organometallic chemistry, on which he had done his PhD thesis, and mass spectrometry, to which he was introduced while a postdoc in Klaus Biemann’s laboratory at the Massachusetts Institute of Technology. In the 1970s, Hunt’s lab pioneered the use of negative chemical ionization (CI) to enhance sensitivity for studying organic molecules, developed a system for simultaneously obtaining positive and negative CI spectra to augment structure elucidation, and built a prototype triple quadrupole instrument so effective at collisional dissociation that its commercial counterpart became the analytical instrument of choice for mixture analysis for the next decade and beyond. Foreseeing that the future lay in the analysis of biological molecules, by the end of the decade Hunt shifted his focus to peptides. The analysis of protein fragments had suddenly become more accessible thanks to the advent of the triple quadrupole and Barber’s invention of fast atom bombardment. As the ‘80s began and Hunt and his team sought to pursue larger and larger pieces of proteins, his attention turned to the development of mass spectrometers with greater mass range. While recounting their memories of these events, several of Hunt’s students and colleagues pay tribute to his support for them as individuals, as well as to his infectious enthusiasm for scientific endeavors that he so generously shared.

Structure-Agnostic Bioactivity-Driven Combinatorial Biosynthesis Reveals New Antidiabetic and Anticancer Triterpenoids.

Although combinatorial biosynthesis can dramatically expand the chemical structures of bioactive natural products to identify molecules with improved characteristics, progress in this direction has been hampered by the difficulty in isolating and characterizing the numerous produced compounds. This challenge could be overcome with improved designs that enable the analysis of the bioactivity of the produced metabolites ahead of the time-consuming isolation procedures. Herein, we showcase a structure-agnostic bioactivity-driven combinatorial biosynthesis workflow that introduces bioactivity assessment as a selection-driving force to guide iterative combinatorial biosynthesis rounds towards enzyme combinations with increasing bioactivity. We apply this approach to produce triterpenoids with potent bioactivity against PTP1B, a promising molecular target for diabetes and cancer treatment. We demonstrate that the bioactivity-guided workflow can expedite the combinatorial process by enabling the narrowing down of more than 1000 possible combinations to only five highly potent candidates. By focusing the isolation and structural elucidation effort on only these five strains, we reveal 20 structurally diverse triterpenoids, including four new compounds and a novel triterpenoid-anthranilic acid hybrid, as potent PTP1B inhibitors. This workflow expedites hit identification by combinatorial biosynthesis and is applicable to many other types of bioactive natural products, therefore providing a strategy for accelerated drug discovery.

Lichen-associated Fungi Inhabiting from a Mangrove Ecosystem in Sri Lanka: A Novel Source of Antibacterial Agents

The global threat of antimicrobial resistance has spurred interest in discovering innovative antimicrobial agents from diverse sources. Amid the rise of new diseases, the quest for novel drug leads has intensified. This study explores the antibacterial potential of lichen-associated fungi in mangrove ecosystems, using NARA Regional Research Centre in Kalpitiya, Sri Lanka as the study site. Lichen-associated fungi were isolated from collected lichens and the antibacterial activities of the isolates were tested using two gram-positive bacteria: Staphylococcus aureus (ATCC 25923) and Bacillus cereus (ATCC 11778) and two gram-negative bacteria: Pseudomonas aeruginosa (ATCC 25853) and Escherichia coli (ATCC 25922). Putative fungal isolates were primarily screened using agar plug diffusion assay and ethyl acetate extracts of fungal isolates with marked activity were secondarily screened using the well diffusion assay in triplicate. Isolate LIF 0803 identified as Trichosporon faecale showed the most outstanding antibacterial activities as 2.58, 3.43, 4.2, 4.5 cm of zone diameter at 100 mg/mL, and 1.95, 3.08, 3.7, 4.3 cm of zone diameter at 50 mg/mL against P. aeruginosa, S. aureus, B. cereus, and E. coli respectively. All nine fungal isolates showed promising antibacterial activity against both gram-positive and negative bacteria. Therefore, this study showed that lichen-associated fungi in mangrove ecosystems have potent antibacterial activities. Hence, bioassay-guided fractionation of active compounds from lichen-associated fungi and structure elucidation are warranted.

Ultrasound-assisted synthesis and structure elucidation of novel quinoline-pyrazolo[1,5-a]pyrimidine hybrids for anti-malarial potential against drug-sensitive and drug-resistant malaria parasites and molecular docking

Ultrasound-assisted synthesis and structure elucidation of novel quinoline-pyrazolo[1,5-a]pyrimidine hybrids for anti-malarial potential against drug-sensitive and drug-resistant malaria parasites and molecular docking

To Gibbs or Not to Gibbs Effect of Entropic Contribution in the NMR Calculations of Flexible and Polar Molecules-Updating the DP4+App.

The application of quantum-based NMR methods for the structural elucidation of natural and unnatural products has grown significantly. However, accurately calculating the conformational landscape of flexible molecules with intricate intramolecular hydrogen bonding (IHB) networks continues to be a major challenge. In this work, we thoroughly studied the effect of entropic contributions (trough Gibbs free energies calculations) in the DP4+ performance. Our results show that to solve biased systems with strong IHB interactions requires computing the Boltzmann contributions using Gibbs free energies computed with at least triple-ξ basis set and SMD solvation model. In response to this finding, we have updated our DP4+App, a user-friendly Python applet that automates the entire process of calculating DP4+ probabilities. In the new version, the program allows for calculating of conformational contributions at any selected theory level, using either SCF or Gibbs free energies.

Syntheses and Properties of Two Isomeric Phenanthroacephenanthrylene Derivatives

Cyclopenta‐annulated polycyclic aromatic hydrocarbons (CP‐PAHs) are of significant interest due to their unique optoelectronic properties and applications in organic electronic devices. Phenanthroacephenanthrylene (PAP) isomers are CP‐PAHs that have been rarely investigated, and only the [9,10‐e]PAP isomer was explored to date. Herein, we report the syntheses, crystal structure and optoelectronic properties of two PAP isomers, 7‐ethoxy[2,1‐e]PAP 1 and 9‐ethoxy[1,2‐e]PAP 2. The structural isomers were synthesized in multi‐steps, and structural elucidations were performed using NMR, mass, and single‐crystal X‐ray diffraction analyses, revealing planar backbone of the isomers. UV‐visible absorption and fluorescence spectra of compound 1 were red‐shifted than that of 2, suggesting smaller HOMO–LUMO energy gap which is further validated by DFT calculations that suggested the lowering of HOMO–LUMO spacing could be attributed to the greater destabilization of HOMO for 1.

Chemical and metabolic profiling of Amaryllidaceae alkaloids in the bulbs of Narcissus tazetta L. var. chinensis Roem using liquid chromatography–tandem mass spectrometry with data mining strategy

RationaleThe bulbs of Narcissus tazetta L. var. chinensis Roem (BNTCR) has been used as an herbal medicine for the treatment of carbuncles in China. The previous phytochemical studies indicated that the main active components of BNTCR were Amarllidaceae alkaloids (AAs). However, the comprehensive chemical and metabolic profiling of AAs in BNTCR remains underexplored. Therefore, it is necessary to establish an accurate and rapid approach for chemical characterization and metabolic profiling of AAs in BNTCR.MethodsThe structural elucidation of natural products by ultra‐high performance liquid chromatography coupled to quadrupole time of flight tandem mass spectrometry (UHPLC‐QTOF‐MS/MS) with outstanding properties is still limited due to complex mixtures that contain hundreds of compounds. In this study, we employed UHPLC‐QTOF‐MS/MS with a data mining strategy, including diagnostic fragment ions (DFIs) and neutral loss (NL), for rapid classifying and identifying AAs in BNTCR and prototypes absorbed into the blood of mice after oral administration of BNTCR extract.ResultsAs a result, 87 AAs, including 13 narciclasine type, 13 homolycorine type, 17 lycorine type, 12 galanthamine type, 25 haemanthamine type, and 7 tazettine type, were tentatively characterized (6 verified with authentic standards). In addition, a total of 44 prototypes were identified in mice plasma, urine, and fecal samples. Among them, 8 prototypes were found in plasma, 36 in urine, and 40 in feces, respectively. Lycorine, pseudolycorine, homolycorine, 8‐O‐demetylhomolycorine, and tazettine, as major AAs in BNTCR, were absorbed into the blood.ConclusionsOur findings provided a crucial step for the elucidation of the active compounds in BNTCR for treatment of carbuncles. In the future, the developed strategy could also be applied for identifying AAs in other herbal medicines from Amarllidaceae.

Discovery of Lacto-N-Biosidases and a Novel N-Acetyllactosaminidase Activity in the CAZy Family GH20: Functional Diversity and Structural Insights.

The glycoside hydrolase family 20 (GH20) predominantly features N-acetylhexosaminidases (EC 3.2.1.52), with only few known lacto-N-biosidases (EC 3.2.1.140; LNBases). LNBases catalyze the degradation of lacto-N-tetraose (LNT), a prominent component of human milk oligosaccharides, thereby supporting a healthy infant gut microbiome development. We investigated GH20 diversity to discover novel enzymes that release disaccharides such as lacto-N-biose (LNB). Our approach combined peptide clustering, sequence analysis, and 3D structure model evaluation to assess active site topologies, focusing on the presence of a subsite -2. Five LNBases were active on pNP-LNB and four showed activity on LNT. One enzyme displayed activity on both pNP-LacNAc and pNP-LNB, establishing the first report of N-acetyllactosaminidase (LacNAcase) activity. Exploration of this enzyme cluster led to the identification of four additional enzymes sharing this dual substrate specificity. Comparing the determined crystal structure of a specific LNBase (TrpyGH20) and the first crystal structure of an enzyme with dual LacNAcase/LNBase activity (TrdeGH20) revealed a highly conserved subsite -1, common to GH20 enzymes, while the -2 subsites varied significantly. TrdeGH20 had a wider subsite -2, accommodating Gal with both β1,4- and β1,3-linkages to the GlcNAc in subsite -1. Biotechnological applications of these enzymes may include structural elucidation of complex carbohydrates and glycoengineering.

Synthesis, Characterization, and Therapeutic Potential of Novel Schiff Base Metal Complexes: Nickel(II) and Copper(II) Complexes Based 2‐[(2‐Chloroquinolin‐3‐yl)methylidene]aminobenzenethiol (CQAT)

ABSTRACTThis research focused on the design and comprehensive characterization of two novel transition metal complexes derived from the symmetrical Schiff base 2‐[(2‐chloroquinolin‐3‐yl)methylidene]aminobenzenethiol (CQAT), coordinated with nickel(II) (NiCQAT) and copper(II) (CuCQAT) ions. The structural elucidation of these complexes was achieved through a range of advanced analytical techniques. Thermal analysis revealed the stability and decomposition patterns of the complexes, supporting the identification of their coordination geometries. The collective data indicated that both NiCQAT and CuCQAT complexes adopt octahedral coordination, with the specific formulas [Ni(CQAT)2(H2O)2] and [Cu(CQAT)2(H2O)2], respectively. To complement the experimental findings, density functional theory (DFT) calculations were employed. These theoretical calculations confirmed the proposed molecular structures and provided detailed insights into key quantum chemical parameters, such as HOMO–LUMO energies, molecular orbitals, and electronic distributions, which are crucial for understanding the complexes' reactivity and stability. Furthermore, extensive in vitro biological evaluations were conducted to assess the anti‐inflammatory and antioxidant properties of the synthesized complexes. These assays demonstrated that both NiCQAT and CuCQAT exhibited significantly enhanced bioactivity compared to the free CQAT ligand, suggesting a synergistic effect of metal coordination on the ligand's biological efficacy. To further explore the mode of action, molecular docking studies were performed targeting two key proteins—human cyclooxygenase‐2 (PDB ID: 5IKT) and human peroxiredoxin 2 (PDB ID: 5IJT). The docking simulations provided valuable insights into the binding affinities, interaction energies, and key amino acid residues involved in the binding process, offering a molecular‐level understanding of their potential biological mechanisms. The findings from these multidisciplinary studies highlight the therapeutic potential of CQAT and its nickel and copper complexes, positioning them as promising candidates for further development in the field of medicinal chemistry.

Fortunefuroic Acid J from Keteleeria Hainanensis and its Dual Inhibitory Effects on ATP-Citrate Lyase and Acetyl-CoA Carboxylase.

A previously undescribed triterpenoid (fortunefuroic acid J, 1) was isolated from the endangered conifer Keteleeria hainanensis, along with 20 other known terpenoids. Compound 1 is characterized by an unusual 3,4-seco-9βH-lanost-3-oic acid motif, featuring a rare furoic acid moiety in its lateral chain. The structure elucidation of this compound was achieved through a combination of spectroscopic and computational methods. The C-15 epimers of 15-methoxypinusolidic acid (15R-8 and 15S-9) were successfully separated and identified for the first time. Compound 1 demonstrated dual inhibitory effects against ATP-citrate lyase (ACL, IC50: 0.92 μM) and acetyl-CoA carboxylase 1 (ACC1, IC50: 10.76 μM). Compounds 2 and 11 exclusively inhibited ACL, exhibiting IC50 values of 2.64 and 6.35 μM, respectively. Compound 1 is classified among the fortunefuroic acid-type compounds, previously isolated from K. fortunei, distinguished by the presence of a rare furoic acid moiety in their lateral chain. The chemotaxonomic significance of the 9βH-lanost-26-oic acids in Keteleeria was briefly discussed. These findings highlight the importance of conserving plant species diversity, thereby enhancing the exploration of structurally diverse compounds and potential avenues for developing new therapeutics targeting ACL/ACC1-associated diseases.