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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]

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]

Anthracene derivatives are an interesting class of compounds and modifications in the anthracene ring, producing different compounds with different properties. Structural analysis of anthracene derivatives with modifications in position 9,10 of the aromatic ring is necessary in order to obtain information about its properties. The introduction of groups with polar substituents increases the possibility to modify the molecule lipophilicity, corroborating its use as bioimaging probes. Anthracene derivatives are used in many biochemical applications. These compounds can react with molecular singlet oxygen [O2 (1Δg)], a reactive oxygen species, through the Diels–Alder reaction [4 + 2] to form the respective endoperoxide and to be used as a chemical trap in biological systems. Thus, the structural and crystalline characterizations of two anthracene derivatives are presented in this work to obtain information about their physical-chemical properties. The compounds were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analyses and scanning electron microscopy. The molecular structures of the compounds were studied by the Density Functional Theory, M06-2X/6-311++G(d,p) level of theory in the gas phase. From the results obtained for the frontier molecular orbitals, HOMO and LUMO, and from the Molecular Electrostatic Potential map, it was possible to predict the chemical properties of both compounds. The supramolecular arrangements were also theoretically studied, whose molecules were kept fixed in their crystallographic positions, through the natural bonding orbitals analysis to check the stability of interactions and the quantum theory of atoms in molecules to verify the type of intermolecular interaction between their molecules, as well as how they occur. [ABSTRACT FROM AUTHOR]

The absolute configuration of strictosidinic acid, (2 S,3 R,4 S)-3-ethenyl-2-(β- d-glucopyranosyloxy)-4-{[(1 S)-2,3,4,9-tetrahydro-1 H-pyrido[3,4- b]indol-1-yl]methyl}-3,4-dihydro-2 H-pyran-5-carboxylate, was determined from its sodium chloride trihydrate, poly[[diaqua((2 S,3 R,4 S)-3-ethenyl-2-(β- d-glucopyranosyloxy)-4-{[(1 S)-2,3,4,9-tetrahydro-1 H-pyrido[3,4- b]indol-2-ium-1-yl]methyl}-3,4-dihydro-2 H-pyran-5-carboxylate)sodium] chloride monohydrate], {[Na(C26H32N2O9)(H2O)2]Cl·H2O} n. The strictosidinic acid molecule participates in intermolecular hydrogen bonds of the O-H...O and O-H...Cl types. The solid-state conformation was observed as a zwitterion, based on a charged pyridine N atom and a carboxylate group, the latter mediating the packing through coordination with the sodium cation. [ABSTRACT FROM AUTHOR]

The title compound, C18H22N2O2S, is of interest with respect to antibacterial and anticancer activity and it has shown good trypanocidal activity. The molecular packing lacks classical hydrogen bonds, being mediated only by weak van der Waals forces. [ABSTRACT FROM AUTHOR]

The title compound, C15H16N2O2S, is of interest with respect to antibacterial and anticancer activity and shows some trypanocidal activity. The crystal structure displays O—H...N hydrogen bonding, forming a chain along [001]. A weak non-classical hydrogen bond of type C—H...S connects molecules across an inversion centre. The packing is also mediated by an intermolecular C=O...π ring interaction connecting centrosymmetrically related molecules. Steric effects are responsible for the molecular conformation. [ABSTRACT FROM AUTHOR]

The title compound, C16H18N2O3S, is of interest with respect to antibacterial and anticancer activity and shows some trypanocidal activity. The crystal packing displays O—H...N and C—H...S hydrogen bonds, forming a chain parallel to the [100] direction. The crystal structure also shows a short intermolecular C=O...π-ring interaction connecting centrosymmetrically related molecules. [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]

The title compound, C15H14N2OS2, adopts a helix conformation. An intra-molecular N-H⋯O hydrogen bond leads to a six-membered pseudo-ring [r.m.s. deviation = 0.0212 Å, maximum deviation = 0.033 (1) Å for the N atom bearing the benzoyl group] in the central unit. The benzene and (methyl-sulfan-yl)benzene ring [r.m.s = 0.0028 Å and largest deviation of 0.067 (3) Å for the methyl-sulfanyl C atom] make dihedral angles of 31.76 (8) and 54.68 (6)°, respectively, with the pseudo-ring plane. The dihedral angle between the benzene rings is 85.71 (8)°. In the crystal, pairs of weak N-H⋯S inter-actions form inversion dimers and mediate a linear chain along [001].

In the title compound, C6H10N2OS, the 2-sulfanylideneimidazolidin-4-one fragment is essentially planar (r.m.s. deviation = 0.0033 Å). In the crystal, one amino group is involved in N-H⋯O hydrogen bonding, which links pairs of mol-ecules into inversion dimers, while the other amino group generates weak N-H⋯S hydrogen bonds, which link these dimers into chains in [10-1]. The chains are further aggregated into layers parallel to the ac plane through weak C-H⋯O inter-actions.

Amaiouine, a cyclopeptide alkaloid, was isolated from the ethanolic extract of the leaves of Amaioua guianensis. The structure was elucidated by NMR spectroscopy and confirmed by X-ray crystallography.

The distribution of the d electrons over the corresponding orbitals in transition-metal complexes is a central concept in the theory of metal-ligand bonding. The description requires the assignment of an axis of quantization, which is unambiguous in symmetric environments but not clear-cut in the now commonly encountered case of a low-symmetry coordination environment. As the d-electron population can be derived from accurate diffraction data using the methods of charge-density analysis [HollaDay et al. (1983). Acta Cryst. A39, 377-387], the need for an appropriate procedure is relevant in this area of crystallography. Several criteria for the choice of coordinate system based on the resulting orbital populations are discussed. They are tested on a cobalt atom in a trigonal bipyramidal site and applied to transition-metal sites in Cu(II)-alanyl-valine, and an open zirconocene. The population of the d-orbital cross terms for the different coordinate-system orientations is used to judge the results. In the cases examined, the intuitively most reasonable coordinate system corresponds to the one with smaller value of the sum of the populations of the d-orbital cross terms.