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A series of novel lanthanide β‐diketonate coordination compounds containing the ancillary ligand bis(diphenylphosphino) oxide (dppeO2) have been synthesized, characterized, and studied spectroscopically. The compounds of formulas Ln(β‐dik)3(dppeO2), where Ln: Eu and Gd and β‐dik ligands as tta (Ln‐1), btf (Ln‐2), bzac (Ln‐5) and tfac (Ln‐4), and Ln2(β‐dik)6(dppeO2) with ligand dbm (Ln‐3) and fod (Ln‐6). Their photophysical properties were investigated from the Judd‐Ofelt intensity parameters (Ωλ ${{\Omega }_{\lambda }}$), radiative (Arad ${{A}_{rad}}$) and non‐radiative (Anrad ${{A}_{nrad}}$) rates, intrinsic (QEuEu ${{Q}_{Eu}^{Eu}}$) and overall (QEuL ${{Q}_{Eu}^{L}}$) quantum yields, and CIE (x,y) color coordinates. The Eu‐5 and Eu‐6 compounds have the first excited triplet states T1 (around 18802 and 18976 cm−1, respectively) almost resonant with the Eu3+ 5D0 emission level, whereas the complexes Eu‐1, Eu‐2, Eu‐3, and Eu‐4 exhibited higher T1 energies. The Arad ${{A}_{rad}}$ values were predominantly driven by the intensity parameter Ω2 ${{\Omega }_{2}}$ , suggesting more pronounced angular changes in the first coordination sphere of the Eu3+ ion. The Anrad ${{A}_{nrad}}$ values also exhibited significant changes with the β‐diketonate ligands. Eu‐1 showed the highest value of QEuL ${{Q}_{Eu}^{L}}$ (60 %), indicating a more efficient intramolecular energy transfer process. On the other hand, Eu‐5 and Eu‐6 compounds showed QEuL ${{Q}_{Eu}^{L}}$ values equal to 18.7 % and 16.5 %, respectively, which indicates the presence of luminescence quencher channels. [ABSTRACT FROM AUTHOR]

This study employs electrochemical and Density Functional Theory (DFT) calculation approaches to investigate the potential of a novel analogue of trimetozine (TMZ) antioxidant profile. The correlation between oxidative stress and psychological disorders indicates that antioxidants may be an effective alternative treatment option. Butylatedhydroxytoluene (BHT) is a synthetic antioxidant widely used in industry. The BHT-TMZ compound derived from molecular hybridization, known as LQFM289, has shown promising results in early trials, and this study aims to elucidate its electrochemical properties to further support its potential as a therapeutic agent. The electrochemical behavior of LQFM289 was investigated using voltammetry and a mechanism for the redox process was proposed based on the compound's behavior. LQFM289 exhibits two distinct oxidation peaks: the first peak, Ep1a ≈ 0.49, corresponds to the oxidation of the phenolic fraction (BHT), and the second peak, Ep2a ≈ 1.2 V (vs. Ag/AgCl/KClsat), denotes the oxidation of the amino group from morpholine. Electroanalysis was used to identify the redox potentials of the compound, providing insight into its reactivity and stability in different environments. A redox mechanism was proposed based on the resulting peak potentials. The DFT calculation elucidates the electronic structure of LQFM289, resembling the precursors of molecular hybridization (BHT and TMZ), which may also dictate the pharmacophoric performance. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis and characterization of the novel Ni(II)(L-threoninato)2(H2O)2 crystal, a bivalent transition metal complex based on Ni(II) ions, based on crystalline structure and thermal properties. Through crystallographic analysis, we reveal that Ni(II)(L-threoninato)2(H2O)2 complex adopts an orthorhombic system with the C2221 space group. To gain insights into its thermal behavior, thermogravimetric analysis, and differential scanning calorimetry techniques were employed to estimate kinetic parameters related to its thermal degradation. Model-free analysis, employing Friedman, Ozawa-Flynn-Wall, and Kissinger-Akahira-Sunose methods, along with model-based analysis, were utilized to evaluate the activation energy and the logarithm of the pre-exponential factor. Furthermore, we elucidated the complex's crystalline structure thermal behavior using Powder X-ray Diffraction measurements as a function of temperature, at air and under vacuum. No phase transitions were detected at low temperatures only at high temperatures due to loss of water molecules. The measurements showed the crystal goes to a partially crystalline anhydrous phase with a certain long-range order in the [001] direction. Through Rietveld refinement the behavior of the lattice parameters and thermal expansion coefficients were obtained. This comprehensive study provides valuable knowledge about the Ni(II)(L-threoninato)2(H2O)2 crystals and lays the foundation for further exploration of similar complexes. 3D-plot of the thermal decomposition showing the TGA curve and the IR spectra of the released gases. XRD pattern showing the crystal keeps a long-range order in the [001] direction during the water loss partial amorphization. Thermal behavior of lattice parameters obtained by Rietveld refinement. [Display omitted] • Synthesis and crystal structure of the novel Ni(II)(L-threoninato) 2 (H 2 O) 2 crystal. • Thermal behavior of the Ni(II)(L-threoninato) 2 (H 2 O) 2 crystal by means of PXRD. • Thermal behavior and kinetic studies using TGA and DSC analysis. • Thermal expansion coefficients in air atmosphere and also under vacuum. • Partially crystalline anhydrous phase with long-range order in [001] direction. [ABSTRACT FROM AUTHOR]

The interaction of (S)-(−)-usnic acid (2) and fumarprotocetraric acid (3), isolated from Cladonia rappii (lichen), and commercial (R)-(+)-usnic acid (1) with urease was investigated in vitro by molecular spectroscopy at pH 7.4 and kinetics experiments using jack bean type III urease. All lichen compounds tested interact with urease by a statistical quenching mechanism forming non-fluorescent complexes that change the native protein structure. Formation of complexes was spontaneous and stabilized mainly by electrostatic forces, in which the interaction magnitude was determined to be 3 ＜ 2 ＜ 1. Compound 2, whose tridimensional structure is disclosed here, acts as a mixed inhibitor while compounds 1 and 3 function as competitive ones. The (R)-(+)-UA (1) is the most efficient lichen metabolite with respect to impairment of the growth of five H. pylori strains. The minimum inhibitory concentrations (MIC) for the lichen metabolites tested were lower (from 2- to 7.8-fold) than those of omeprazole (reference drug) against all H. pylori strains tested. Overall, the lichen metabolites 1–3 are promising lead compounds for the design of more efficient urease inhibitors for the treatment of H. pylori infections. [ABSTRACT FROM AUTHOR]

This study shows the design, synthesis and antitumoral potential evaluation of a novel chalcone-like compound, ( E )-3- (3, 5-di- ter- butyl-4-hydroxyphenyl)-1- (4-hydroxy-3-methoxyphenyl) prop-2-en-1-one [LQFM064) ( 4 )], against human breast adenocarcinoma MCF7 cells. Some toxicological parameters were also investigated. LQFM064) ( 4 ) exhibited cytotoxic activity against MCF7 cells (IC 50 = 21 μM), in a concentration dependent-manner, and triggered significant changes in cell morphology and biochemical/molecular parameters, which are suggestive of an apoptosis inductor. LQFM064) ( 4 ) (21 μM) induced cell cycle arrest at G0/G1 phase with increased p53 and p21 expressions. It was also shown that the compound ( 4 ) did not interfere directly in p53/MDM2 complexation of MCF7 cells. In these cells, externalization of phosphatidylserine, cytochrome c release, increased expression of caspases-7, − 8 and − 9, reduced mitochondrial membrane potential and ROS overgeneration were also detected following LQFM064 ( 4 ) treatment. Further analysis revealed the activation of both apoptotic pathways via modulation of the proteins involved in the extrinsic and intrinsic pathways with an increase in TNF-R1, Fas-L and Bax levels and a reduction in Bcl-2 expression. Furthermore, KIT proto-oncogene receptor tyrosine kinase, insulin-like growth factor (IGF1) and platelet-derived growth factor receptor A (PDGFRA) were downregulated, while glutathione S-transferase P1 (GSTP1) and interferon regulatory factor 5 (IRF5) expressions were increased by LQFM064 ( 4 )-triggered cytotoxic effects in MCF7 cells. Moreover, it can be inferred that compound ( 4 ) has a moderate acute oral systemic toxicity hazard, since its estimated LD 50 was 452.50 mg/kg, which classifies it as UN GHS Category 4 (300 mg/kg > LD 50 < 2000 mg/kg). Furthermore, LQFM064 ( 4 ) showed a reduced potential myelotoxicity (IC 50 = 150 μM for mouse bone marrow hematopoietic progenitors). In conclusion, LQFM064 ( 4 ) was capable of inducing breast cancer cells death via different cytotoxic pathways. Thus, it is a promising alternative for the treatment of neoplasias, especially in terms of the drug resistance development. [ABSTRACT FROM AUTHOR]

The potential of tert -butyl hydroperoxide as a reagent in the guanylation of benzoylthioureas in the presence of amines has been evaluated in a systematic study involving substrates bearing N 2 -substituents with different electronic properties. The results show that t BuOOH is a suitable and robust reagent for the synthesis of either N 1 , N 2 , N 3 -tri- and tetrasubstituted or N 1 , N 2 -disubstituted guanidines from N 2 -substituted N 1 -benzoylthioureas and N 1 -benzoylthioureas, respectively. The recrystallised guanylation adducts were readily obtained in good yields and at high purity levels after a simple one-pot reaction procedure. The crystal structures of two novel benzoylguanidines are provided. [ABSTRACT FROM AUTHOR]

• LQFM219 acts as a free radical scavenger, reducing MPO, TNF-α, and IL-1β levels. LQFM219 is a molecule designed from celecoxibe (COX-2 inhibitor) and darbufelone (inhibitor of COX-2 and 5-LOX) lead compounds through a molecular hybridisation strategy. Therefore, this work aimed to investigate the antinociceptive and anti-inflammatory activities of this new hybrid compound. The acute oral systemic toxicity of LQFM219 was evaluated via the neutral red uptake assay. Acetic acid-induced abdominal writhing and CFA-induced mechanical hyperalgesia were performed to evaluate the antinociceptive activity, and the anti-oedematogenic activity was studied by CFA-induced paw oedema and croton oil-induced ear oedema. Moreover, the acute anti-inflammatory activity was determined by carrageenan-induced pleurisy. In addition, cell migration, myeloperoxidase enzyme activity, and TNF-α and IL-1β levels were determined in pleural exudate. Moreover, a redox assay was conducted using electroanalytical and DPPH methods. The results demonstrated that LQFM219 was classified as GHS category 4, and it showed better free radical scavenger activity compared to BHT. Besides, LQFM219 decreased the number of writhings induced by acetic acid and the response to the mechanical stimulus in the CFA-induced mechanical hyperalgesia test. Furthermore, LQFM219 reduced oedema formation, cell migration, and IL-1β and TNF-α levels in the pleural cavity and inhibited myeloperoxidase enzyme activity. Thus, our study provides that the new pyrazole derivative, LQFM219, demonstrated low toxicity, antinociceptive and anti-inflammatory potential in vitro and in vivo. [ABSTRACT FROM AUTHOR]