[1]研究活動

Protein sequences of the ABCA transporters of the eight species. (XLSX 25 kb

Solubility of the Schiff Base Ligand and the Organoaluminum Supported by the Ligand in Pure Solvents: Characterization, Determination, Analysis, and Model Correlation

Schiff bases and organoaluminum compounds have wide applications in medicine and catalysis. TG-DSC provided melting points and melting enthalpies for the Schiff base ligand (1, 2-[[(2,6-difluorophenyl)­imino]­methyl]­phenol, CAS: 26672-04-8), with Tm at 349.55 K and ΔHfus at 22.797 kJ/mol, and for the organoaluminum compound supported by the ligand (2, [2-[[(2,6-difluorophenyl)­imino]­methyl]­phenoxy]­dimethylaluminum, CAS: 2851050-89-8), with Tm at 396.04 K and ΔHfus at 11.137 kJ/mol. The range of molecular electrostatic potentials for the two compounds was obtained by molecular electrostatic potential analysis, with the potential range for compound 1 being from +95.1 kJ/mol to −133.2 kJ/mol and that for compound 2 being from +139.9 kJ/mol to −132.7 kJ/mol. Hirshfeld surface analysis indicated that H···H contacts were the dominant contact interactions in these two molecules. In addition, the solubilities of the two compounds in 11 pure solvents were determined, and experimental data were correlated using 7 thermodynamic equations. The results displayed that the NRTL model had the best correlation result for the two compounds. These experimental results will have significant implications for the purification, crystallization, and industrial applications of similar types of substances

Electrophilic <i>N</i>‑Trifluoromethylation of N–H Ketimines

A direct <i>N</i>-trifluoromethylation method has been developed by the use of the <i>in situ</i> generated [ArICF₃]⁺ species as the electrophilic trifluoromethyl source. Upon treatment of N–H ketimines with Ruppert–Prakash reagent in the presence of PhI­(OAc)₂ and KF, or with Togni’s reagent II catalyzed by copper salt, <i>N</i>-trifluoromethylated imine products were obtained in moderate to good yields

A new sesquiterpene from the entomogenous fungus <i>Phomopsis amygdali</i>

<div><p>A new sesquiterpene, (+)-<i>S</i>-1-methyl-abscisic-6-acid (<b>1</b>), together with five known compounds, (+)-<i>S</i>-abscisic acid (<b>2</b>), fusicoccin J (<b>3</b>), 3α-hydroxyfusicoccin J (<b>4</b>), (<i>R</i>)-5-hydroxymethylmellein (<b>5</b>) and 4-hydroxyphenethyl acetate (<b>6</b>) was isolated from the fermentation extract of <i>Phomopsis amygdali</i>, an entomogenous fungus isolated from <i>Call midge</i>. Their structures were determined mainly by analysis of MS and NMR spectroscopic data. Compounds <b>1</b>–<b>6</b> were tested for antimicrobial activity against three plant pathogenic fungi: <i>Gibberella zeae</i>, <i>Verticillium albo-atrum</i>, and <i>Fusarium nivale</i>, and two bacteria: <i>Escherichia coli</i> and <i>Pseudomonas aeruginosa</i> 2033E. As a result, compounds <b>1</b>–<b>4</b> displayed antibacterial activity against Gram-negative <i>P. aeruginosa</i> 2033E, and the minimum inhibition concentration (MIC value) of <b>1</b>–<b>4</b> is 30 μg/mL, 58 μg/mL, 26 μg/mL, and 26 μg/mL, respectively.</p></div

Effect of Dicarboxylate Ligands on the Construction of Cd(II) Complexes Based on a Flexible Bis-Triazole Ligand

<div><p>In this work, two dicarboxylate ligands, 4,4′-oxybis(benzoic acid) (H₂oba) and 4,4′-biphenyldicarboxylic acid (H₂bpdc) were employed as coligands to perform a comparison on the structures of Cd(II)-btmx complexes (btmx = 1,4-bis(1,2,4-triazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene) motifs. Two new complexes, {[Cd(btmx)(oba)]·H₂O}_n (1) and [Cd(btmx)(bpdc)]_n (2), have been synthesized and characterized. Structural analyses show that 1 shows a 1D double-chain, while 2 displays an undulating 2D 4⁴-<i>sql</i> network with 2-fold interpenetration. The structural differences of the two complexes suggest that the dicarboxylate ligands have great impact on the formation of such coordination architectures. Furthermore, the photoluminescence properties of 1 and 2 have also been investigated.</p></div

Screening of α‑Glucosidase Inhibitors in Cichorium glandulosum Boiss. et Huet Extracts and Study of Interaction Mechanisms

Cichorium glandulosum Boiss. et Huet (CGB) extract has an α-glucosidase inhibitory effect (IC50 = 59.34 ± 0.07 μg/mL, positive control drug acarbose IC50 = 126.1 ± 0.02 μg/mL), but the precise enzyme inhibitors implicated in this process are not known. The screening of α-glucosidase inhibitors in CGB extracts was conducted by bioaffinity ultrafiltration, and six potential inhibitors (quercetin, lactucin, 3-O-methylquercetin, hyperoside, lactucopicrin, and isochlorogenic acid B) were screened as the precise inhibitors. The binding rate calculations and evaluation of enzyme inhibitory effects showed that lactucin and lactucopicrin exhibited the greatest inhibitory activities. Next, the inhibiting effects of the active components of CGB, lactucin and lactucopicrin, on α-glucosidase and their mechanisms were investigated through α-glucosidase activity assay, enzyme kinetics, multispectral analysis, and molecular docking simulation. The findings demonstrated that lactucin (IC50 = 52.76 ± 0.21 μM) and lactucopicrin (IC50 = 17.71 ± 0.64 μM) exhibited more inhibitory effects on α-glucosidase in comparison to acarbose (positive drug, IC50 = 195.2 ± 0.30 μM). Enzyme kinetic research revealed that lactucin inhibits α-glucosidase through a noncompetitive inhibition mechanism, while lactucopicrin inhibits it through a competitive inhibition mechanism. The fluorescence results suggested that lactucin and lactucopicrin effectively reduce the fluorescence of α-glucosidase by creating lactucin-α-glucosidase and lactucopicrin-α-glucosidase complexes through static quenching. Furthermore, the circular dichroism (CD) and Fourier transform infrared spectroscopy (FT-IR) analyses revealed that the interaction between lactucin or lactucopicrin and α-glucosidase resulted in a modification of the α-glucosidase’s conformation. The findings from molecular docking and molecular dynamics simulations offer further confirmation that lactucopicrin has a robust binding affinity for certain residues located within the active cavity of α-glucosidase. Furthermore, it has a greater affinity for α-glucosidase compared to lactucin. The results validate the suppressive impact of lactucin and lactucopicrin on α-glucosidase and elucidate their underlying processes. Additionally, they serve as a foundation for the structural alteration of sesquiterpene derived from CGB, with the intention of using it for the management of diabetic mellitus

Reactivity Studies of LAlH₂ (L = HC(CMeNAr)₂, Ar = 2,6‑<i>i</i>Pr₂C₆H₃) with 2‑Aminobenzenethiol, 2‑Aminophenol, and 1,4-Dithiane-2,5-diol

The reaction of LAlH₂ (L = HC­(CMeNAr)₂, Ar = 2,6-<i>i</i>Pr₂C₆H₃) (<b>1</b>) with 2-aminobenzenethiol, 2-aminophenol, and 1,4-dithiane-2,5-diol resulted in the compounds LAl­[(μ<i>-</i>N)­(μ<i>-</i>S)]­(<i>o</i>-C₆H₄) (<b>2</b>), LAl­[(μ<i>-</i>O)­(<i>o</i>-C₆H₄)­(NH₂)]₂ (<b>3</b>), and LAl­(μ<i>-</i>O)₂(<i>p</i>-dithiane) (<b>4</b>), respectively. Compound <b>2</b> features an organic–inorganic hybrid containing an NAlSC₂ five-membered ring, while compound <b>3</b> exhibits a C–O–Al–O–C chain structure. Compound <b>4</b> forms a basket-like molecule with the C₄S₂ unit as the bottom part and O₂Al as the handle. Complexes <b>2</b>, <b>3</b>, and <b>4</b> were characterized by ¹H NMR, elemental analysis, and single-crystal X-ray diffraction studies

Aluminum Complexes Containing the C–O–Al–O–C Framework as Efficient Initiators for Ring-Opening Polymerization of ε‑Caprolactone

Three aluminum complexes, LAl­(OCH₂C₆H₄-2-NH₂)₂ (<b>2</b>), LAl­(9-OC₁₃H₉)₂ (<b>3</b>), and LAl­(OC₆H₁₀-4-NH₂)₂ (<b>4</b>), were synthesized in good yield by reacting one equivalent of LAlH₂ (<b>1</b>) (L = HC­(CMeNAr)₂, Ar = 2,6-<i>i</i>Pr₂C₆H₃) with two equivalents of 2-aminobenzyl alcohol, 9-hydroxyfluorene, and <i>trans</i>-4-aminocyclohexanol, respectively. All complexes (<b>2</b>, <b>3</b>, and <b>4</b>) contain the C–O–Al–O–C framework. These complexes have been characterized by IR, ¹H and ¹³C NMR, elemental analyses, and single-crystal X-ray structural analysis. Furthermore, the excellent catalytic activities of <b>2</b>, <b>3</b>, and <b>4</b> for ring-opening polymerization of ε-caprolactone in the presence of isopropyl alcohol were investigated

Reactivity Studies of LAlH₂ (L = HC(CMeNAr)₂, Ar = 2,6‑<i>i</i>Pr₂C₆H₃) with 2‑Aminobenzenethiol, 2‑Aminophenol, and 1,4-Dithiane-2,5-diol

The reaction of LAlH₂ (L = HC­(CMeNAr)₂, Ar = 2,6-<i>i</i>Pr₂C₆H₃) (<b>1</b>) with 2-aminobenzenethiol, 2-aminophenol, and 1,4-dithiane-2,5-diol resulted in the compounds LAl­[(μ<i>-</i>N)­(μ<i>-</i>S)]­(<i>o</i>-C₆H₄) (<b>2</b>), LAl­[(μ<i>-</i>O)­(<i>o</i>-C₆H₄)­(NH₂)]₂ (<b>3</b>), and LAl­(μ<i>-</i>O)₂(<i>p</i>-dithiane) (<b>4</b>), respectively. Compound <b>2</b> features an organic–inorganic hybrid containing an NAlSC₂ five-membered ring, while compound <b>3</b> exhibits a C–O–Al–O–C chain structure. Compound <b>4</b> forms a basket-like molecule with the C₄S₂ unit as the bottom part and O₂Al as the handle. Complexes <b>2</b>, <b>3</b>, and <b>4</b> were characterized by ¹H NMR, elemental analysis, and single-crystal X-ray diffraction studies

α5-nAChR/AKT signaling involved in anti-apoptotic effects of nicotine in cisplatin-induced apoptosis of BGC823 cells.

<p>A: P-AKT was activated after exposure to 100μM nicotine in BGC823 cells (lane 2 and lane3). Cisplatin strongly suppressed activity of P-AKT (lane 1 and lane 2) but nicotine also induced P-AKT in the presence of cisplatin (lane 2 and lane 3). Down-regulation of α5-nAChR expression decreased the level of P-AKT (lane 4 and lane 5). Treatment with LY294002 downregulated P-AKT expression (lane 3 and lane 5). Combination LY294002 with si-CHRNA5 transfection significantly repressed the nicotine induced P-AKT protein levels (lane 3 and lane 6); *p<0.05; B: Cisplatin induced an increase in caspase-3 and Bax activation in BGC823 cells a decrease in Bcl-2 and Survivin expressions, whereas nicotine blocked cisplatin- induced Bcl-2, Bax, caspase-3 and Survivin expressions; With silence of α5-nAChR co-administrated LY294002, an increased apoptosis was observed with the induction of Bcl-2, Bax, Survivin and Caspase-3 by nicotine in BGC823 cells. *p<0.05; C: Assessment of apoptosis by AnnexinV/7-AAD staining in each group. BGC823 cells were pre-treated with 100 μM nicotine and cisplatin for 24 h, and/or si-α5-nAChR for 48h, and/or AKT inhibitor LY294002 for 24h, and harvested.</p