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The interaction of decavanadate with the cationic organic dyes methylene blue (MB), toluidine blue (TB) and rhodamine B (RB) was explored. For that purpose, a novel decavanadate salt (2,3-ampH)6[V10O28]·4H2O (2,3-ampV10), where 2,3-ampH+ = 2-amino-3-methylpyridinium, and two salts with the organic dyes (MB)4[H2V10O28]·10.8H2O (MBV10) and (TB)4(H2V10O28)·10H2O (TBV10) were synthesized. The compounds were characterized by elemental analysis, powder X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy and infrared spectroscopy. The salts 2,3-ampV10 and MBV10 were also characterized by single-crystal X-ray diffraction, while TBV10 was isolated as an amorphous solid. The supramolecular features of MBV10 showed columns of MB cations connected to V10 through H-bond interactions that resulted in channels filled with water molecules. The absorption spectrum of MBV10 was studied by density functional theory (DFT) calculations at the X3LYP/def2-TZVP level using the crystallographic data. The efficacy of 2,3-ampV10 to bleach MB solutions at pH 6.2–6.5 was outstanding, achieving nearly 90% discoloration in only 5 min, presenting moderate efficacy towards TB and quite negligible towards RB. Moreover, a metachromatic effect was observed in the TB solution at pH 3. The IR spectra of the isolated solids and the mass spectra of the supernatants suggest both adsorption and cation exchange as the main responsible processes for the bleaching of MB and TB solutions. The present work has tackled many fronts related to the chemistry of POVs, mainly synthetic, structural, and environmental approaches. [ABSTRACT FROM AUTHOR]

In this work, the study of the new ligand 3,3′-bis[N,N-bis(pyridine-2-ylmethyl)aminomethyl]-2,2′-dihydroxybiphenyl (L) is reported, where a central 2,2′-biphenol (BPH) fluorophore was functionalized at 3,3′-positions with two dipicolylamine (DPA) side arms as receptor units. Following the synthesis and full chemical–physical characterization, the acid–base and Zn2+-coordination abilities of L were investigated through a combination of potentiometric, UV-Vis, fluorescence, NMR, XRD and DFT measurements. The optical properties of the ligand turned out to be strongly dependent on the pH, being straightforwardly associated with the protonation state of the BPH moiety, whereas its peculiar design allowed to form stable mono and dinuclear Zn2+ complexes. In the latter species, the presence of two Zn2+ ions coordinatively unsaturated and placed at close distance to each other, prompted us to test their usefulness as metallo-receptors for two environmental pollutants of great relevance, ibuprofen and ketoprofen. Potentiometric and fluorescence investigations evidenced that these important non-steroidal anti-inflammatory drugs (NSAIDs) are effectively coordinated by the metallo-receptors and, of relevance, both the stability and the fluorescence properties of the resulting ternary adducts are markedly affected by the different chemical architectures of the two substrates. This study aims at highlighting the promising perspectives arising from the use of polyamino phenolic ligands as chemosensors for H+/Zn2+ and other additional anionic targets in their metal-complexed forms. [ABSTRACT FROM AUTHOR]

The globally widespread perfluorooctanoic acid (PFOA) is a concerning environmental contaminant, with a possible toxic long-term effects on the environment and human health The development of sensible, rapid, and low-cost detection systems is a current change in modern environmental chemistry. In this context, two triamine-based chemosensors, L1 and L2, containing a fluorescent pyrene unit, and their Zn(II) complexes are proposed as fluorescent probes for the detection of PFOA in aqueous media. Binding studies carried out by means of fluorescence and NMR titrations highlight that protonated forms of the receptors can interact with the carboxylate group of PFOA, thanks to salt bridge formation with the ammonium groups of the aliphatic chain. This interaction induces a decrease in the fluorescence emission of pyrene at neutral and slightly acidic pH values. Similarly, emission quenching has also been observed upon coordination of PFOA by the Zn(II) complexes of the receptors. These results evidence that simple polyamine-based molecular receptors can be employed for the optical recognition of harmful pollutant molecules, such as PFOA, in aqueous media. [ABSTRACT FROM AUTHOR]

The tetranuclear Cu2+/Ca2+/Ca2+/Cu2+ complex based on Malten ligand has been investigated as a platform for anion binding. Simple organic carboxylates and non‐steroidal anti‐inflammatory drugs (NSAIDs) have been tested, revealing the ability of the platform to bind them. The receiving platform hosts at least two guests in solution although a third anion can be bound, as suggested by X‐ray diffraction analysis. The addition of the anions is accompanied by a color change of the solution, making the system a colorimetric sensor for carboxylates (LOD values comprised between 3.6 and 20.7 ppm). A fluorescent system consisting of the 2‐(3‐oxido‐6‐oxoxanthen‐9‐yl)benzoate (fluorescein anion) linked to the tetranuclear platform has been also prepared and used in a chemosensing ensemble approach to signal the presence of the selected anions (Log K between 2.6 and 5.6 for the addition of two guests). The latter also works in a paper strip test, offering the chemosensor a possible practical application. [ABSTRACT FROM AUTHOR]

Pannexins are an interesting new target in medicinal chemistry, as they are involved in many pathologies such as epilepsy, ischemic stroke, cancer and Parkinson's disease, as well as in neuropathic pain. They are a family of membrane channel proteins consisting of three members, Panx-1, Panx-2 and Panx-3, and are expressed in vertebrates. In the present study, as a continuation of our research in this field, we report the design, synthesis and pharmacological evaluation of new quinoline-based Panx-1 blockers. The most relevant compounds 6f and 6g show an IC50 = 3 and 1.5 µM, respectively, and are selective Panx-1 blockers. Finally, chemical stability, molecular modelling and X-ray crystallography studies have been performed providing useful information for the realization of the project. [ABSTRACT FROM AUTHOR]

Very few sodium complexes are available as precursors for the syntheses of sodium-based nanostructured materials. Herein, the diglyme, triglyme, and tetraglyme (CH3O(CH2CH2O)nCH3, n = 2–4) adducts of sodium hexafluoroacetylacetonate were synthesized in a single-step reaction and characterized by IR spectroscopy, 1H, and 13C NMR. Single-crystal X-ray diffraction studies provide evidence of the formation of the ionic oligomeric structure [Na4(hfa)6]2−•2[Na(diglyme2]+ when the diglyme is coordinated, while a mononuclear seven-coordinated complex Na(hfa)•tetraglyme is formed with the tetraglyme. Reaction with the monoglyme (CH3OCH2CH2OCH3) does not occur, and the unadducted polymeric structure [Na(hfa)]n forms, while the triglyme gives rise to a liquid adduct, Na(hfa)•triglyme•H2O. Thermal analysis data reveal great potentialities for their applications as precursors in metalorganic chemical vapor deposition (MOCVD) and sol-gel processes. As a proof-of-concept, the Na(hfa)•tetraglyme adduct was successfully applied to both the low-pressure MOCVD and the sol-gel/spin-coating synthesis of NaF films. [ABSTRACT FROM AUTHOR]

Triamine receptors containing anthracene units are able to bind and sense ketoprofen via fluorescence enhancement in a H2O/EtOH 50 : 50 (Vol : Vol) mixture exploiting their protonation features, which are tuned by the interaction with the analyte. [ABSTRACT FROM AUTHOR]

Herein we describe the binding abilities of Zn(II) complexes of [12]aneN4- (L1) and [9]aneN3-based receptors (L2, L3) towards the herbicides N-(phosphonomethyl)glycine (glyphosate, H3PMG) and 2-amino-4-[hydroxy(methyl)phosphoryl]butanoic acid (glufosinate, H2GLU), and also aminomethylphosphonic acid (H2AMPA), the main metabolite of H3PMG, and phosphate. All ligands form stable Zn(II) complexes, whose coordination geometries allow a possible interaction of the metal center with exogenous anionic substrates. Potentiometric studies evidenced the marked coordination ability of the L2/Zn(II) system for the analytes considered, with a preferential binding affinity for H3PMG over the other substrates, in a wide range of pH values. 1H and 31P NMR experiments supported the effective coordination of such substrates by the Zn(II) complex of L2, while fluorescence titrations and a test strip experiment were performed to evaluate whether the H3PMG recognition processes could be detected by fluorescence signaling. [ABSTRACT FROM AUTHOR]

One‐dimensional (1D) coordination polymers (CPs) featuring three different topologies, comprising zig‐zag, ribbon‐like and poly‐[n]‐catenane structures, were obtained by reaction of Hg(II) ions with a novel bispidine ligand L3, and structurally characterized by SC‐ and P‐XRD methods. The CPs obtained in the form of microcrystalline powders were tested for their ability to undergo solvent adsorption and exchange by P‐XRD and 1H NMR spectroscopy. The extent of their dynamic behavior was then correlated to their structural features, highlighting the role of interchain interactions established among their constituting linear arrays. Zig‐zag CPs proved to be resilient to external chemical stimuli, while they differently respond to thermal treatments, depending on the solvent originally included within the CP. In the case of polycatenated structures, we observed transformations where the original topology was maintained upon guest exchange, but also cases where it changed to zig‐zag, even under solid/vapor conditions (i. e. no complete dissolution of the CP). Given the presence of linear interconnected 1D channels, 3 ⋅ ClBz‐polycatenanePwd is also able to trap volatile guests such as n‐hexane when exposed to its vapors. [ABSTRACT FROM AUTHOR]

The synthesis, solution studies, photochemical properties and the X-ray structure of a chromone based fluorescent PdII complex are reported. The ligand contains two chromone units linked as side arms to an ethylenediamine moiety; in the PdII complex the metal ion preorganizes the two hydroxychromone units forming a rigid structure with a negatively charged pocket formed by four oxygen atoms that is able to interact with hard metal cations, such as ions, giving rise to stable bimetallic complexes. Upon interaction with LaIII and GdIII, in particular, the emission intensity at 423 nm increases by a factor of 2 and 8, respectively, while the other rare earth ions quench the fluorescence. Spectrofluorimetric studies on real matrices showed the possibility to use this system as a selective fluorescence probe to detect and trace the presence of Gadolinium in environmental water acting as an OFF–ON chemosensor, with a LOD of 0.4 ppm and a LOQ of 1.2 ppm. [ABSTRACT FROM AUTHOR]

N‐formyl peptide receptors (FPR1, FPR2, and FPR3) play key roles in the regulation of inflammatory processes, and recently, it was demonstrated that FPR1 and FPR2 have a dual role in the progression/suppression of some cancers. Therefore, FPRs represent an important therapeutic target for the treatment of both cancer and inflammatory diseases. Previously, we identified selective or mixed FPR agonists with pyridazinone or pyridinone scaffolds showing a common 4‐(bromophenyl)acetamide fragment, which was essential for activity. We report here new pyrazole and pyrazolone derivatives as restricted analogues of the above 6‐membered compounds, all exhibiting the same 4‐bromophenylacetamide side chain. Most new products had low or absent FPR agonist activity, suggesting that the pyrazole nucleus was not appropriate for FPR agonists. This hypothesis was confirmed by molecular modeling studies, which highlighted that the five‐membered scaffold was responsible for a worse arrangement of the molecules in the receptor binding site. [ABSTRACT FROM AUTHOR]

The synthesis of three new polyamine receptors based on a common 1,4,8,11-tetraazacyclododecane (cyclen) platform with appended, via a methylene linker, heteroaromatic fluorophores, a single quinoline (Q) or an 8-hydroxy-quinoline (8-OH-Q) moiety (L1 and HL2) or a Q and an 8-OH-Q unit (HL3), is reported. The proton binding features of these receptors, together with those of two similar receptors containing two equal Q moieties (L4) and two Q and two acetate groups (H2L5), have been studied by means of potentiometric, 1H NMR, UV-vis absorption and fluorescence emission measurements in aqueous solution at different pH values. While cyclen is a commonly used binding unit, Q and 8-OH-Q represent classical examples of signalling units in conjugated fluorescent chemosensors and their protonation features can strongly influence their ability in metal cations, and anion coordination and sensing. This study reveals that the structural features of these receptors are controlled by a subtle balance between hydrogen bonding and electrostatic repulsions occurring in their protonated species. At the same time, their emission properties are tuned by photoinduced electron and/or proton transfer processes taking place in the excited state. [ABSTRACT FROM AUTHOR]

Potassium complexes are starting to gather more and more interest from academia and industry because of their intriguing application possibilities. Novel adducts of potassium hexafluoroacetylacetonato [K(hfa)] with polyethers (monoglyme, diglyme, triglyme, and tetraglyme) were synthesized through a single step reaction and characterized through FT‐IR spectroscopy as well as 1H and 13C NMR spectroscopy. Single crystal X‐ray diffraction studies enabled the identification of fascinating K coordination polymeric networks. [ABSTRACT FROM AUTHOR]

Two new maltol-based ligands are presented, L1 (N,N′-bis((3-hydroxy-6-methyl-4-pyron-2-yl)methyl)-N,N′-dimethylethylenediamine) and L2 (N,N′-bis((3-hydroxy-6-hydroxymethyl-4-pyron-2-yl)methyl)-N,N′-dimethylethylenediamine). They were strategically designed by inserting a methyl or hydroxymethyl function at C6, to study the previously hypothesized involvement of that ring position in the anticancer properties and the peculiar metal coordination ability in aqueous solution already shown by this family of ligands. Solid state and solution studies revealed differences neither in the molecular conformation or crystal packing nor in the acid–base behavior compared with the precursor Malten. The introduced substituent groups seem to affect instead both the degradation time (ca. 4–5 h for L1 and L2vs. 10 h for Malten) and the binding properties towards Cu(II), Zn(II) and Co(II), log K values being the highest for L1 within the series of the diamino-bis-maltol ligands. The introduction of –CH2OH at C6 is sufficient to impair the biological activity of the compound and is coherent with the hypothesized mechanism of action. [ABSTRACT FROM AUTHOR]

The synthesis, photochemical properties, biological effects and the X-ray crystal structure of a fluorescent polyamine macrocycle L are reported. L is a polyamine cyclophane macrocycle in which 2,6-bis(5-(2-methylphenyl)-1,3,4-oxadiazol-2-yl)pyridine (POXAPy) acts as a fluorescent sensor and the polyamine as a metal ion binding unit. L performs as a PET-mediated chemosensor, with a maximum emission wavelength close to 360 nm. This gives rise to a signal that is visible to the naked eye in the blue visible range. L is able to detect the Zn(II) and Cd(II) metal ions in an aqueous solution at pH = 7, with the coordination of the ions switching the emission ON through a CHEF effect. In contrast, paramagnetic metal ions like Cu(II) and Ni(II) completely quench the already low emission of L at this pH value. L affects the cell survival of a leukemic cellular model (U937) at micromolar concentrations with cell death starting after only 24 h of exposure; starting from a final concentration of 5 μM, L almost completely abrogates the survival of the leukemic cells over 72 h, with a mechanism that is compatible with a genomic DNA interaction. [ABSTRACT FROM AUTHOR]

The hetero‐tetranuclear Cu2+/Ca2+/Ca2+/Cu2+ complex obtained with the N,N'‐bis((3‐hydroxy‐4‐pyron‐2‐yl)methyl)‐N,N'‐dimethylethylendiamine (Malten) ligand has been studied in solid and solution states as scaffold to bind anions. Three crystal structures showing the same metal ions sequence have been examined; they display a tetracharged complex cation neutralized by four monocharged anions. The anions play two different roles: as coordinated (two ClO4−, Cl− or NO3−) or ancillary (two ClO4−) guests. The tetranuclear scaffold hosts two anions also in aqueous and ethanol solutions. Spectrophotometric studies in ethanol allowed to determine the addition constant values for Cl− and Br− (Log K1‐2=4.43(4), 4.39(3) for Cl−, 3.80(3), 3.54(2) for Br−) while the others, although bound, showed lower affinity for the scaffold. Both the crystals and the solutions change their color depending on the added anion, namely pink, dark green or blue in the presence of ClO4−, Cl− or NO3−, respectively, thus the presence of the different anions is visible to the naked eye. The hetero‐tetranuclear Cu2+/Ca2+/Ca2+/Cu2+ complex is a versatile architecture to be used as scaffold for anion binding. [ABSTRACT FROM AUTHOR]

Human neutrophil elastase (HNE) is a proteolytic enzyme belonging to the serine protease family and is involved in a variety of pathologies. Thus, compounds able to inhibit HNE represent promising therapeutics for the treatment of inflammatory diseases. Here, we report the further elaboration of our previously reported 3‐methylisoxazolone derivatives, synthesizing a new series of 3‐nor‐derivatives bearing different substituents at the 4‐phenyl ring. The most potent compounds 3a, 3g, and 3h, had IC50 values of 16, 11, and 18 nM, respectively. Molecular modeling studies and molecular dynamic (MD) simulations demonstrated no substantial differences between the 3‐methylisoxazole derivatives previously tested and the corresponding 3‐unsubstituted derivatives in the snapshot conformations sampled during the MD simulations, which is consistent with their similar levels of HNE inhibitory activity. Thus, we conclude that the isoxazolone scaffold is a good scaffold for developing HNE inhibitors, as it tolerates several modifications when adhering to basic scaffold requirements, and the resulting derivatives are quite potent HNE inhibitors. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of the two new open‐chain ligands 1,15‐bis‐[6‐(2,2’‐bipyridyl)]‐2,5,8,11,14‐pentaaza‐octadecane (L1) and 1,15‐bis‐[2‐(1,10‐phenanthroline)‐9‐methyl]‐2,5,8,11,14‐pentaazaoctadecane (L2), both featuring a tetraethylenpentaamine chain linking via methylene bridges the 6 and 2 positions of two identical 2,2’‐bipyridyl (bpy) and 9‐methyl‐1,10‐phenanthroline (9‐methyl‐phen) moieties respectively, are reported. Their protonation and binding ability for Cu2+, Zn2+, Cd2+ and Pb2+ have been studied by coupling potentiometric titrations with UV‐vis absorption and fluorescence emission measurements in water. L1 and L2 afford stable mono‐ and dinuclear complexes, in which the metal ion is bound by a single bpy or 9‐methyl‐phen unit and the amine groups on the aliphatic chain. However, L1 displays a greater binding ability for Cu2+ and Zn2+ with respect to L2, the stability constants of the [ML1]2+ complexes being 21.8 (Cu2+) and 19.4 (Zn2+) log units vs 20.34 and 16.8 log. units for the corresponding L2 species. Among all the metal ions tested, only the Zn2+ complex with L2 features an enhanced fluorescence emission at neutral pH, thanks to the simultaneous binding of one Zn2+ ion and H+ ion(s), that inhibits any possible photoinduced electron transfer (PET) process from the amine donors to the excited phen moiety. Binding of a second metal switches off the emission again. [ABSTRACT FROM AUTHOR]

A ligand comprised of a macrocyclic pyridinophane core having a pendant arm containing a secondary amine group linked through a methylene spacer to a pyridyl–oxadiazole–phenyl (PyPD) fluorescent system has been prepared (L). The crystal structures of [ZnL](ClO4)2 and [CuL](ClO4)2 show that M2+ is coordinated to all the nitrogen atoms of the macrocyclic core, the secondary amine of the pendant arm and the nitrogen atom of the pyridine group of the fluorescent moiety, the latter bond being clearly weaker than the one with the pyridine of the macrocycle. Solution studies showed the formation of a highly stable Cu2+ complex with 1 : 1 stoichiometry, whereas with Zn2+ least stable complexes were formed and, given the right conditions, a [Zn3L2]6+ species was also detected, but it was not possible to isolate this species in the solid state. Following Zn2+ coordination, a strong chelation-induced enhancement of fluorescence was observed, a behaviour that was not observed with any of the other metal cations tested. [ABSTRACT FROM AUTHOR]

Novel adducts of lithium hexafluoroacetylacetonato {Li(hfa)} with polyethers (monoglyme = {CH3OCH2CH2OCH3}, diglyme = {CH3O(CH2CH2O)2CH3}, triglyme = {CH3O(CH2CH2O)3CH3} and tetraglyme {CH3O(CH2CH2O)4CH3} have been synthesized through a single step reaction and characterized by FT-IR spectroscopy, 1H, and 13C NMR, single crystal X-ray diffraction studies along with thermal analysis. [ABSTRACT FROM AUTHOR]

Dexketoprofen [(2S)‐2‐(3‐benzoylphenyl)propanoic acid], C16H14O3, is the S‐enantiomer of ketoprofen, a nonsteroidal anti‐inflammatory drug (NSAID) that has analgesic, antipyretic and anti‐inflammatory properties, and finds applications for the short‐term treatment of mild to moderate pain. A new crystalline phase of dexketoprofen is reported. Its solid‐state structure was determined by single‐crystal X‐ray diffraction (SCXRD). The molecular structure of the two independent molecules found in the asymmetric unit of this new phase (DXKP‐β) were compared to those of the already known crystal form of dexketoprofen (DXKP‐α) and with the S‐enantiomer of the racemic compound. The three different conformers of dexketoprofen found in DXKP‐α and DXKP‐β were then investigated by computational methods. The optimized structures are very close to the corresponding starting geometries and do not differ significantly in energy. The crystal packing of DXKP‐β was studied by means of Hirshfeld surface (HS) analysis; interaction energies were also calculated. A comparison with DXKP‐α shows close similarities between the two crystal forms, i.e. in both cases, molecules assemble through the catemer O—H...O synthon of the carboxylic acid stabilized by additional C—H...O contacts and, accordingly, the interaction energies, as well as the contributions to the HS area, are very similar. Finally, the thermal behaviour of the two polymorphs of dexketoprofen was assessed by means of XRD (both from single crystal and microcrystalline powder) and differential scanning calorimetry (DSC); both crystal forms are stable under the experimental conditions adopted (air, 300–350 K for DXKP‐α and 300–340 K DXKP‐β) and no solid–solid phase transition occurs between the two crystal forms in the investigated temperature range (from 100 K up to ca 350 K). [ABSTRACT FROM AUTHOR]

Metoprolol {systematic name: (RS)‐1‐isopropylamino‐3‐[4‐(2‐methoxyethyl)phenoxy]propan‐2‐ol}, C15H25NO3, is a cardioselective β1‐adrenergic blocking agent that shares part of its molecular skeleton with a large number of other β‐blockers. Results from its solid‐state characterization by single‐crystal and variable‐temperature powder X‐ray diffraction and differential scanning calorimetry are presented. Its molecular and crystal arrangements have been further investigated by molecular modelling, by a Cambridge Structural Database (CSD) survey and by Hirshfeld surface analysis. In the crystal, the side arm bearing the isopropyl group, which is common to other β‐blockers, adopts an all‐trans conformation, which is the most stable arrangement from modelling data. The crystal packing of metoprolol is dominated by an O—H...N/N...H—O pair of hydrogen bonds (as also confirmed by a Hirshfeld surface analysis), which gives rise to chains containing alternating R and S metoprolol molecules extending along the b axis, supplemented by a weaker O...H—N/N—H...O pair of interactions. In addition, within the same stack of molecules, a C—H...O contact, partially oriented along the b and c axes, links homochiral molecules. Amongst the solid‐state structures of molecules structurally related to metoprolol deposited in the CSD, the β‐blocker drug betaxolol shows the closest analogy in terms of three‐dimensional arrangement and interactions. Notwithstanding their close similarity, the crystal lattices of the two drugs respond differently on increasing temperature: metoprolol expands anisotropically, while for betaxolol, an isotropic thermal expansion is observed. The metoprolol free base has been characterized in the solid state by X‐ray diffaction (both single‐crystal and variable‐temperature powder diffraction) and differential scanning calorimetry. These studies are supplemented by molecular modelling and Hirshfeld surface analysis. Structural relationships with the strictly related betaxolol are discussed. [ABSTRACT FROM AUTHOR]

We report the synthesis and biological evaluation of a new series of 3- or 4-(substituted)phenylisoxazolones as HNE inhibitors. Due to tautomerism of the isoxazolone nucleus, two isomers were obtained as final compounds (2-NCO and 5-OCO) and the 2-NCO derivatives were the most potent with IC50 values in the nanomolar range (20-70 nM). Kinetic experiments indicated that 2-NCO 7d and 5-OCO 8d are both competitive HNE inhibitors. Molecular modelling on 7d and 8d suggests for the latter a more crowded region about the site of the nucleophilic attack, which could explain its lowered activity. In addition molecular dynamics (MD) simulations showed that the isomer 8d appears more prone to form H-bond interactions which, however, keep the reactive sites quite distant for the attack by Ser195. By contrast the amide 7d appears more mobile within the active pocket, since it makes single H-bond interactions affording a favourable orientation for the nucleophilic attack. [ABSTRACT FROM AUTHOR]

The title compound, [CaCo2(C22H30N4O6)2](ClO4)2·1.36H2O or {Ca[Co(H–2L1)]2}·2ClO4·1.36H2O {where L1 is 4,10-bis­[(3-hy­droxy-4-pyron-2-yl)meth­yl]-1,7-dimethyl-1,4,7,10-tetra­aza­cyclo­dodecane}, is a trinuclear complex whose asymmetric unit comprises a quarter of the {Ca[Co(H–2L1)]2}2+ trinuclear complex, half of a perchlorate ion and 0.34-water mol­ecules. In the neutral [Co(H–2L1)] moiety, the cobalt ion is hexa­coordinated in a trigonal–prismatic fashion by the surrounding N4O2 donor set. A Ca2+ cation holds together two neutral [Co(H–2L1)] moieties and is octa­coordinated in a distorted trigonal–dodeca­hedral fashion by the surrounding O atoms belonging to the deprotonated oxide and carbonyl groups of two [Co(H–2L1)] units. The coordination of the CoII cation preorganizes L1 and an electron-rich area forms, which is able to host hard metal ions. The comparison between the present structure and the previously published ones suggests a high versatility of this ligand; indeed, hard metal ions with different nature and dimensions lead to complexes having different stoichiometry (mono- and dinuclear monomers and trinuclear dimers) or even a polymeric structure. The heterotrinuclear CoII–CaII–CoII complexes are connected in three dimensions via weak C—H...O hydrogen bonds, which are also responsible for the inter­actions with the perchlorate anions and the lattice water mol­ecules. The perchlorate anion is disordered about a twofold rotation axis and was refined giving the two positions a fixed occupancy factor of 0.5. The crystal studied was refined as a two-component inversion twin [BASF parameter = 0.14 (4)]. [ABSTRACT FROM AUTHOR]

The title compound, {[Ba{Co(H-2L1)}(ClO4)(H2O)]ClO4}n, L1 = 4,10-bis­[(3-hy­droxy-4-pyron-2-yl)meth­yl]-1,7-dimethyl-1,4,7,10-tetra­aza­cyclo­dodeca­ne, is a one-dimensional coordination polymer. The asymmetric unit consists of a {Ba[Co(H–2L1)](ClO4)(H2O)}+ cationic fragment and a non-coordinating ClO4− anion. In the neutral [Co(H–2L1)] moiety, the cobalt ion is hexa­coordinated in a trigonal–prismatic fashion by the surrounding N4O2 donor set. The Ba2+ ion is nine-coordinated and exhibits a distorted [BaO9] monocapped square-anti­prismatic geometry, the six oxygen atoms coming from three distinct [Co(H–2L1)] moieties, while the remaining three vertices are occupied by the oxygen atoms of a bidentate perchlorate anion and a water mol­ecule. A barium–μ2-oxygen motif develops along the a axis, connecting symmetry-related dinuclear BaII–CoII cationic fragments in a wave-like chain, forming a one-dimensional metal coordination polymer. Non-coordinating ClO4− anions are located in the space between the chains. Weak C—HO hydrogen bonds involving both coordinating and non-coordinating perchlorate anions build the whole crystal architecture. To our knowledge, this is the first example of a macrocyclic ligand forming a BaII-based one-dimensional coordination polymer, containing CoII ions surrounded by a N4O2 donor set. [ABSTRACT FROM AUTHOR]

By means of X-ray diffraction analysis the solid state structure of the diprotonated species of the ligandL1_Me(9,12-Dimethyl-9,12,27,28-tetraaza-15,18-dithia-29-oxatetracyclo[24.2.1.02,7.020,25]-enneicosa-2,4,6,20,22,24,26,281-octaene), a macrocycle containing amixedsulfur-nitrogen set of donor atoms decorated with the PPD signaling group, and of its dinuclear platinum complex was investigated . The information retrieved were used as starting point for a deep computational study. Then, with the aim to get hints for the design of possibly improved strictly related receptors, the molecular modeling study was extended to theall-nitrogen ligandL2_Hwhich, at variance withL1_Me,has four nitrogen atoms as donors. Finally, to complete the modeling investigation we design the related ligandsL1_H,L2_MeandL3_Hon which computational studies were performed. The aim was to investigate and try to rationalise the parameters affecting the overall shape of the host-guest adducts. [ABSTRACT FROM AUTHOR]

A new tetraglyme adduct of sodium hexafluoroacetylacetonate [Na(hfa)·tetraglyme] has been synthesized and successfully used, together with the RE(hfa)3·diglyme (RE = Y, Yb, Er) complexes, in the synthesis of hexagonal phase NaYF4:Yb3+,Er3+ upconverting films through a facile sol–gel method. [ABSTRACT FROM AUTHOR]

A variety of studies have shown that group identification (a sense of belonging to one's social group, coupled with a sense of commonality with the group's members) is linked to high levels of satisfaction with life (SWL). The aim of the present study was to support and extend this literature by: (1) investigating the link between group identification and SWL with a large cross-cultural community sample; (2) examining whether the relationship is moderated by nationality; and (3) considering whether SWL is enhanced by possessing multiple group identifications simultaneously. Utilizing data from Wave 1 of the Health in Groups project, 3829 participants from both Scotland and Italy completed a questionnaire assessing their identification with their family, their local community, and a group of their choice, as well as their level of SWL. Higher identification with each group predicted higher SWL. Nationality was a marginal moderator of the relationship between family identification and SWL, with the relationship being stronger for Italian participants than for Scottish participants. There was also an additive effect of group identification, with a positive relationship between the number of groups with which participants identified and their SWL. These effects were obtained even after controlling for gender, age, employment status, nationality, and extent of contact with each group. The implications for healthcare professionals and their patients are discussed. [ABSTRACT FROM AUTHOR]

Cover Feature: A Tetranuclear Copper(II)/Calcium(II) Complex as Dual Chemosensor for Colorimetric and Fluorescent Detection of Non-Steroidal Anti-Inflammatory Drugs (ChemPlusChem 5/2023) Anti-inflammatory drugs, chemosensors, coordination chemistry, maltol ligands, tetranuclear complexes Keywords: anti-inflammatory drugs; chemosensors; coordination chemistry; maltol ligands; tetranuclear complexes EN anti-inflammatory drugs chemosensors coordination chemistry maltol ligands tetranuclear complexes 1 1 1 05/30/23 20230501 NES 230501 B The cover feature image depicts b a tetranuclear Cu SP 2+ sp /Ca SP 2+ sp /Ca SP 2+ sp /Cu SP 2+ sp maltol-based platform, which has been proposed as a tool for the detection and sequestering of anionic species via a colorimetric mechanism or an indirect fluorescent sensing. [Extracted from the article]

The N, N′-bis[(3-hydroxy-4-pyron-2-yl)methyl]- N, N′-dimethylethylendiamine (Malten= L) forms the highly stable [CuH−2 L] species in water, in which the converging maltol oxygen atoms form an electron-rich area able to host hard metal ions. When considering the alkaline earth series (AE), the [Cu(H−2 L)] species binds all metal ions, with the exception of Mg2+, exhibiting the relevant property to discriminate Ca2+ versus Mg2+ at physiological pH 7.4; the binding of the AE metal is visible to the naked eye. The stability constant values of the trinuclear [AE{Cu(H−2 L)}2]2+ species formed reach the maximum for Ca2+ (log K=7.7). Ca2+ also forms a tetranuclear [Ca{Cu(H−2 L)}]24+ species at a high Ca2+ concentration. Tri- and tetranuclear calcium complexes show blue- and pink-colored crystals, respectively. [Cu(H−2 L)] is the most active species in inducing DNA alterations. The DNA damages are compatible with its hydrolytic cleavages. [ABSTRACT FROM AUTHOR]

The complex, Mn(hfa)2•tmeda [(H-hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentandione, tmeda = N,N,N′,N′-tetramethylethylendiamine)], is synthesized in a single-step reaction and characterized by elemental analysis, thermal analysis, and infrared (IR) spectroscopy. The solid-state crystal structure of Mn(hfa)2•tmeda provides evidence of a mononuclear structure. The thermal analyses show that the complex is thermally stable and can be evaporated to leave less than 2% residue. The complex properties are compared with the first generation, commercially available MnII and MnIII precursors, Mn(acac)2 (Hacac = acetylacetone) and Mn(tmhd)3 (Htmhd = 2,2,6,6-tetramethyl-3,5-heptanedione), respectively. Mn(hfa)2•tmeda represents the first example of manganese(II) precursor that can be used in the liquid phase without decomposition, thus providing constant evaporation rates, even for long deposition times. It is successfully applied to the reduced-pressure, metal-organic (MO)CVD of the Mn3O4 phase. [ABSTRACT FROM AUTHOR]

Preliminary studies of the elementary steps involved in the reaction of a chiral methyl carbonyl bioxazoline Pd(ii) complex with aromatic olefins and CO have allowed development of a new enantioselective catalytic carbonylation process, leading to γ-ketoester derivatives with high yield and good enantiomeric excess. The intermediate palladacycle complexes have been isolated and characterized by NMR spectroscopy and X-ray diffraction. Factors that govern the stereoselectivity of the olefin carbonylation process are discussed. [ABSTRACT FROM AUTHOR]

Customized synthetic procedures for the obtainment of highly functionalizable free sulfonamide tricyclic structures having NH, O, S and SO2(Z group) in the central seven-membered ring are presented. Due to the role that tricycles and the sulfonamide group play in medicinal chemistry, attention have been also paid to the 3D arrangement of these molecules. Their molecular structures and conformational properties have been studied by single-crystal X-ray diffraction and quantum chemical methods (HF-SCF/6-311+G(d,p). The minimum energy geometries in the solid state (I, Z = O; II, Z = NH and III, Z = S, SO2) have been compared with the minimum-energy geometries in the gas phase (invariably the type IIIgeometry) and discussed with respect to the literature reference values. An effort was made to correlate the conformational differences observed in the solid-state and gas-phase with the nature of the Z grouping. [ABSTRACT FROM AUTHOR]

The human tachykinin NK-2 (hNK-2) receptor is considered a promising target for relevant pathologies at the respiratory, gastrointestinal and genitourinary level. With the aim of reducing the complexity of existing peptide antagonists, two series of hNK-2 receptor antagonists were designed, with the support of modelling, and synthesized. The X-ray structure determination of two compounds, each belonging to one of the two series, allowed the experimental validation of the initial rationale. In addition, it has been found that the two series share a β-turn structure, a key feature for binding the hNK-2 receptor. [ABSTRACT FROM AUTHOR]

The structures of three β-lactam penem antibiotics—i.e. the sodium[5R-[5α,6α(R*)]]-6-(1-hydroxyethyl)-7-oxo-3-[[(1-pyrrolidinylthioxomethyl)thio]methyl]-4-thia-1-azabicyclo[3.2.0] hept-2-ene-2-carboxylate (compound 1), the [5R-[3(S*),5α,6α(R*)]]-3-[[2-(aminocarbonyl)-1-pyrrolidinyl] methyl]-6-(1-hydroxyethyl)-7-oxo-4-thia-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid (compound 2), and the [5R-[5α,6α(R*)]]-3-[[(2-amino-2-oxoethyl) methylamino]methyl]-6-(1-hydroxyethyl)-7-oxo-4-thia-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid (compound 3)—have been determined by X-ray analyses. In the crystal lattice two conformational isomers of 1 are present, which differ from each other in the spatial arrangement of the dithiocarbamate chain. Compounds 2 and 3 are in zwitterionic form, being the hydrogen of the carboxylic acid moved to the amino nitrogen of the chain at C2. This hydrogen atom, in both molecules, forms intramolecular hydrogen bonds with an oxygen atom of the carboxylate moiety and with the oxygen atom of the amido group of the side chain. The 3D structures of 1, 2, and 3 have been compared with those of previously reported β-lactam penem antibiotics. Particularly, the Woodward parameter and the Cohen distance, which are considered important in determining the antibiotic activity, have been discussed. Least-squares minimizations (RMS) of the distances between nuclei of selected pairs of atoms defining the pharmacological pattern have been performed, comparing five common antibiotics (imipenem, ritipenem, cephaloridine, amoxycillin, and benzylpenicillin) with our compounds. Finally, molecular dynamics calculations have been carried out on the three penem antibiotics at different temperatures. The conformational behavior of the hydroxyethyl chain, the carboxylate group, and the chain at C2 is discussed by considering the variation of some selected dihedral angles. [ABSTRACT FROM AUTHOR]