Iridium-based Polymeric Multifunctional Imaging Tools for Biochemistry.

Herein, we report the development of a macromolecular multifunctional imaging tool for biological investigations, which is comprised of an N-(2-hydroxypropyl)methacrylamide backbone, iridium-based luminescent probe, glutamate carboxypeptidase II (GCPII) targeting ligand, and biotin affinity tag. The iridium luminophore is a tris-cyclometalated complex based on [Ir(ppy)3] with one of its 2-phenylpyridine ligands functionalized to allow conjugation. Synthesized macromolecular probes differed in the structure of the polymer and content of the iridium complex. The applicability of the developed imaging tools has been tested in flow cytometry (FACS) based assay, laser confocal microscopy, and fluorescence lifetime imaging microscopy (FLIM). The FACS analysis has shown that the targeted iBodies containing the iridium luminophore exhibit selective labelling of GCPII expressing cells. This observation was also confirmed in the imaging experiments with laser confocal microscopy. The FLIM experiment has shown that the iBodies with the iridium label exhibit a lifetime greater than 100 ns, which distinguishes them from typically used systems labelled with organic fluorophores exhibiting short fluorescence lifetimes. The results of this investigation indicate that the system exhibits interesting properties, which supports the development of additional biological tools utilizing the key components (iridium complexes, iBody concept), primarily focusing on the longer lifetime of the iridium emitter.

Isolation of Fatty Acids from the Enzymatic Hydrolysis of Capsaicinoids and Their Use in Enzymatic Acidolysis of Coconut Oil.

Herein we report the optimization of enzymatic hydrolysis of a mixture of capsaicinoids, capsaicin and dihydrocapsaicin obtained from chili peppers, and the utilization of the isolated fatty acids for the modification of coconut oil using enzyme catalyzed acidolysis. This work was carried out as the fatty acids that can be isolated from capsaicinoid hydrolysis have been shown to possess interesting biological properties. These biological properties could be better exploited by incorporating the fatty acids into a suitable delivery vehicle. The enzymatic hydrolysis of the mixture of capsaicin and dihydrocapsaicin was carried out using Novozym® 435 in phosphate buffer (pH 7.0) at 50℃. The enzyme catalyst could be reused in multiple cycles of the hydrolysis reaction. The desired 8-methyl-6-trans-nonenoic acid and 8-methylnonanoic acid were isolated from the hydrolysis reaction mixture using a simple extraction procedure with a 47.8% yield. This was carried out by first extracting the reaction mixture at pH 10 with ethyl acetate to remove any dissolved capsaicinoids and vanillyl amine side product. The fatty acids were isolated after adjustment of the pH of the reaction mixture to 5 and second extraction with ethyl acetate. The acidolysis of coconut oil with the obtained fatty acids was performed using Lipozyme® TL IM. The performance of the acidolysis reaction was evaluated using 1H-NMR spectroscopy and verified in selected cases using gas chromatography. The best performing conditions involved carrying out the acidolysis reaction at 60℃ with a 1.2 w/w ratio of the fatty acids to coconut oil and 10% enzyme loading for 72 h. This resulted in the incorporation of 26.61% and 9.86% of 8-methyl-6-trans-nonenoic acid and 8-methylnonanoic acid, respectively, into the modified coconut oil product. This product can act as a potential delivery vehicle for these interesting compounds.

Reduction of lauric acid content in virgin coconut oil improved plasma lipid profile in high-fat diet-induced hypercholesterolemic mice.

Virgin coconut oil (VCO) is claimed to have various health benefits, but favorable effects of its major component (∼50%), lauric acid, are controversial. Therefore, we aimed to reduce lauric acid content (∼30%) in VCO and evaluate its effect compared to VCO and medium-chain triglycerides (MCT), on food intake, bodyweight (BW), lipid profiles, and hepatic histology. Female C57BL/6 mice were treated with different diets for 3 months: control (normal diet), high-fat diet (HF), HF + VCO, HF + MCT, HF + low lauric acid VCO (LLA), and normal diet + LLA (C + LLA). LLA was prepared by enzymatic interesterification of VCO with methyl octanoate (methyl caprylate) and methyl decanoate (methyl caprate). Plasma and liver lipids, including total cholesterol (TC), high-density lipoprotein (HDL), and triglyceride, were measured by colorimetric assay, and hepatic fat accumulation was examined by oil-red-O staining. HF mice exhibited high plasma and liver TC and low-density lipoprotein (LDL). VCO or MCT treatment lowered liver TC and LDL, whereas LLA increased plasma HDL and markedly improved TC:HDL ratio. The HF-induced hepatic fat accumulation was attenuated by all treatments, of which VCO was the most effective. Control mice administered with LLA demonstrated lower liver TC and LDL, but higher plasma TC and HDL compared to controls. Lowest BW gain and food intake were found in mice treated with LLA. In conclusion, VCO, MCT, and LLA ameliorated hepatic histopathology caused by HF. VCO and MCT improved liver lipid profiles, whereas LLA has more beneficial effect on plasma lipids via a better TC:HDL ratio and showed promise for BW control.

Incrementing MCT Character of Coconut Oil Using Enzyme Catalyzed Interesterification.

The fatty acid composition of coconut oil was modified using enzyme catalyzed interesterification with the aim of obtaining a product more alike to commercial MCT oils. This modification was carried out with the aim to obtain a product with some of the health benefits shown by MCT oils. Initially, lipase B from Candida antarctica immobilized on acrylic resin and lipozyme TL IM were tested as enzyme catalysts for the reaction. The enzyme catalysts have shown similar performance and lipozyme TL IM has been chosen as the catalyst based on its lower cost. The effects of reaction time, oil to methyl octanoate ratio, and enzyme loading on the reaction performance have been investigated with response surface methodology (RSM) utilizing the Box-Behnken approach. The optimized reaction was scaled up to 20 g. The possibility to source the medium chain fatty acid esters from coconut oil fatty acid distillate using a simple procedure was demonstrated and the possibility to use these esters for the interesterification of coconut oil has been demonstrated as well.

Four series of lanthanide coordination polymers based on the tetrabromobenzene-1,4-dicarboxylate ligand: structural diversity and multifunctional properties.

Four series of lanthanide-based coordination polymers (LnCPs), namely [Ln(Br4bdc)1.5(MeOH)3] (1Ln; Ln = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy), [Ln2(Br4bdc)2(NO3)2(MeOH)4] (2Ln; Ln = Ce, Pr, Nd, Sm), [Ln(Br4bdc)(NO3)(MeOH)] (3Ln; Ln = Gd, Tb, Dy), and [Ln2(Br4bdc)3(H2O)2.3(MeOH)2.7] (4Ln; Ln = Gd, Tb, Dy) have been synthesized by reacting hydrated lanthanide(III) salts with tetrabromobenzene-1,4-dicarboxylic acid (H2Br4bdc) in different solvents under solvothermal conditions. The structural diversity found in the system mainly resulted from the effects of anions, solvents, and the variation in the ionic radii of the lanthanide(III) ions. Compounds in series 1Ln feature a two-dimensional (2D) layered structure with sql topology based on {(Ln(COO)2)2(µ-COO)2} secondary building units (SBUs). Compounds in series 2Ln and 3Ln comprise, respectively, infinite uniform and alternate chains of {Ln(COO)2}n SBUs that are assembled into a similar network topology to 1Ln. Meanwhile, compounds in series 4Ln feature 3D coordination networks of a pcu α-Po topological net consisting of binuclear {Ln2(COO)3} SBUs. The formation of polymeric networks in series 1Ln-4Ln is facilitated by the numerous coordination sites of the ligand Br4bdc2- and the fact that its bromine atoms can participate in the formation of various types of intermolecular interactions. The solid-state photoluminescence studies on Eu- (1Eu) and Tb- (1Tb, 3Tb, 4Tb) containing compounds indicate that the Br4bdc2- ligands can efficiently sensitize Eu3+ and Tb3+ emission. Notably, such compounds exhibit highly sensitive fluorescence sensing for acetone, water, and Fe3+ ions via the fluorescence quenching effect. As the representatives of the series, activated 1Eu, 2Pr, 3Tb, and 4Tb show the maximum CO2 uptake capacities of 170.4, 273.7, 255.3, and 303.5 cm3 g-1, respectively, at 50 bar and 298 K with good repeatability of the adsorption-desorption properties. Magnetic studies indicate that the Gd- and Dy-based compounds 1Gd, 1Dy, 3Gd, 3Dy, and 4Gd show simple paramagnetic behaviours, whereas compound 4Dy exhibits weak ferromagnetic interactions.

Self-Assembly of 1D Double-Chain and 3D Diamondoid Networks of Lanthanide Coordination Polymers through In Situ-Generated Ligands: High-Pressure CO2 Adsorption and Photoluminescence Properties.

Two new lanthanide-based coordination polymers, [Sm2(bzz)(ben)6(H2O)3]·0.5H2O (1) and [Eu(bbz)(ben)3] (2), were synthesized and characterized. The described products were formed from in situ-generated benzoate (ben) and N'-benzoylbenzohydrazide (bbz) ligands, which were the products of transformation of originally added benzhydrazide (bzz) under hydrothermal conditions. Compound 1 exhibits a one-dimensional (1D) double-chain structure built up from the connection of the central Sm3+ ions with a mixture of bzz and ben ligands. On the other hand, 2 features a 3D network with a 4-connected (66) dia topology constructed from dinuclear [Eu2(ben)6] secondary building units and bbz linkers. High-pressure CO2 sorption studies of activated 1 show that maximum uptake increases to exceptionally high values of 376.7 cm3 g-1 (42.5 wt%) under a pressure of 50 bar at 298 K with good recyclability. Meanwhile, 2 shows a typical red emission in the solid state at room temperature with the decay lifetime of 1.2 ms.

Coordination-driven self-assembly of a series of dinuclear M2L2 mesocates with a bis-bidentate pyridylimine ligand.

Four isostructural dinuclear M2L2 mesocates of the general formula [M2(NCS)4(L)2]·4.5MeOH (1M; M = Mn, Fe, Co, Zn) were constructed by using the coordination-driven self-assembly of the [M(NCS)2] precursor and the flexible bis-bidentate pyridylimine Schiff base ligand L (L = 4,4'-(1,4-phenylenebis(oxy))bis(N-(pyridin-2-ylmethylene)aniline). The centrosymmetric M2L2 mesocate forms through the side-by-side coordination of two L ligands to a pair of M(ii) ions. The mesocates exhibit a reversible temperature induced desolvation-solvation behavior without losing their structural integrity. The activated 1Co, as the representative M2L2 mesocate, shows an exceptionally high MeOH vapour uptake capacity of 481.9 cm3 g-1 (68.8 wt%) at STP with good recyclability. Notably, it also exhibits CO2 adsorption with an uptake capacity of 20.2 cm3 g-1 (3.6 wt%) at room temperature and 1 bar.

The coordination chemistry of benzhydrazide with lanthanide(iii) ions: hydrothermal in situ ligand formation, structures, magnetic and photoluminescence sensing properties.

The influence of synthetic conditions on the solid-state structural formation of lanthanide(iii) complexes based on a hydrazide ligand have been investigated and reported. Depending on the solvents and reaction temperatures, the reactions of hydrated Ln(NO3)3 with a benzohydrazide (bzz) ligand afforded three classes of lanthanide(iii) coordination complexes viz. [Ln(bzz)(NO3)](NO3)2 (1Ln; Ln = Sm (1), Eu (2), Gd (3), Tb (4), Dy (5)), [Ln(bzz)(ben)3(H2O)]·H2O (2Ln; Ln = Pr (6), Nd (7), Sm (8), Eu (9), Gd (10), Tb (11), Dy (12), Er (13)), and [Ln3(ben)3] (3Ln; Ln = Eu (14), Gd (15), Tb (16), Dy (17), Er (18), Tm (19), Yb (20), Lu (21)). Complexes 1-5 in series 1Ln were isolated by slow evaporation of their isopropanol solutions at ambient temperature, and the complexes display similar discrete structures bearing distinct intermolecular N-H⋯O hydrogen bonds to generate a three-dimensional (3D) supramolecular architecture. Complexes 6-13 in series 2Ln were obtained under hydrothermal conditions at 110 °C where the in situ generated benzoate (ben) ligands participated in the formation of one-dimensional (1D) coordination polymers (CPs) with the bzz ligands. At a temperature of 145 °C the hydrothermal conditions result in the formation of the thermodynamically more stable products of 14-21 in series 3Ln, in which the bzz ligand underwent complete in situ hydrolysis to create the ben ligand. These coordination assemblies feature 1D zigzag chains that are formed by unusual low coordination numbers of the six- and seven-fold coordinated Ln3+ centers bridged by the ben ligands in µ 2- and µ 3-coordination modes. Notably, the chain structures of 2Ln can be transformed into the zigzag tape-like structures of 3Ln upon heating the crystalline samples to 400 °C in air. In the solid state at room temperature, the Eu- (2, 9, 14) and Tb- (4, 11, 16) containing complexes emit red and green light, respectively. The luminescence investigations show that the Eu- (9, 14) and Tb-(11, 16) based CPs could be used as fluorescent probes for acetone and Co2+ ions via an energy competition mechanism. Meanwhile, the Gd- (10, 15) and Dy- (12, 17) based CPs show typical antiferromagnetic interactions.

Oxygen-deficient bismuth molybdate nanocatalysts: Synergistic effects in boosting photocatalytic oxidative coupling of benzylamine and mechanistic insight.

Herein, bismuth molybdate (Bi2MoO6) nanocatalysts containing oxygen vacancies (OVs) are found to considerably promote the photocatalytic performance toward oxidative coupling of benzylamine to N-benzylidenebenzylamine under visible light irradiation. The structure-activity relationship for this interesting catalyst is revealed for the first time. The oxygen-deficient Bi2MoO6 nanoplatelets (BMO-NPs) are synthesized using ethylene glycol-ethanol solvent mixture as a reaction medium in solvothermal method. A comparison with hydrothermally prepared Bi2MoO6 square-like sheets (BMO-SHs) suggests that the nanoplatelets are much smaller in size and contain higher amount of OVs. Benzylamine conversion over the BMO-NPs is ca. 4.0 times higher than that over the BMO-SHs and ca. 3.8 and ca. 34.6 times higher than that over the commercial benchmark TiO2 P25 and BiVO4 catalysts, respectively. The BMO-NPs achieve more than 80% product yield within 2 h of irradiation regardless of substituents of benzylamine derivatives. The enhanced activity of BMO-NPs is due to synergistic roles of high surface-to-volume ratio and OVs, providing enlarged active area, extended light absorption range and improved charge separation and transfer efficiency as evidenced from UV-vis DRS, BET surface area, photocurrent response, electrochemical impedance spectroscopy, and time-resolved fluorescence decay measurements. EPR-trapping and radical scavenging experiments indicate O2- as a main active species rather than 1O2 and a plausible imine formation mechanism via O2--assisted charge transfer is proposed accordingly. The work offers an alternative facile preparation method to design efficient semiconductor photocatalysts and for the first time reveals a possible benzylamine coupling mechanism over the oxygen-deficient Bi2MoO6 nanocatalyst.

Selective enrichment of zein gene of maize from cereal products using magnetic support having pyrrolidinyl peptide nucleic acid probe.

Here, we describe DNA enrichment of the zein gene from maize using pyrrolidinyl peptide nucleic acid (PNA) immobilized on a magnetic solid support as a capture element. Magnetite nanoparticles (MNP) with a capacity of 373 pmolPNA/mg and coated with poly(N-acryloylglycine) (PNAG) showed a good response to magnetic field. The PNA probe immobilized on the MNP discriminated between non-complementary and complementary DNA using fluorophore-tagged DNA as a model. We applied this system for the enrichment of the zein gene from maize in eight cereal product samples. After DNA desorption from the MNP, and its amplification via polymerase chain reaction (PCR), gel electrophoresis indicated that only cereal samples containing the zein gene from maize yielded positive results, indicating a high binding specificity between the PNA used and the complementary DNA. This PNA-functionalized MNP is potentially useful as an effective nano-solid support for DNA enrichment from other samples.

Dual Function Based on Switchable Colorimetric Luminescence for Water and Temperature Sensing in Two-Dimensional Metal-Organic Framework Nanosheets.

A simple, rapid, highly selective, and real-time determination of water is urgently required for preventing danger from water contamination in materials. Herein, the excited-state proton transfer (ESPT) concept-based luminescent sensor [Cd2(2,5-tpt)(4,5-idc)(H2O)4] (1) (2,5-tpt = 2,5-dihydroxyterephthalic acid and 4,5-idc = 4,5-imidazoledicarboxylic acid) has been designed for discriminative detection via enol-keto tautomerism. To improve the sensitivity, two-dimensional (2D) nanosheets of 1 have been synthesized by top-down liquid ultrasonic exfoliation technology for sensing water in dimethylformamide, which lead to fast detection (<30 s), high selectivity, broad-range detection (0-50% v/v), and a low detection limit value (0.25% v/v). This sensor can serve dual sensing mechanisms along with a luminescent color change via shifted emission (green→yellow) in low water content and a turn-off method in high water content. For ease of use, the test-strip paper-based 2D nanosheets of 1 have been prepared and applied for water detection with long-term stability, pH stability, and good reusability. On-site water detection in real time can be evaluated using a smartphone color-scanning application for quantitative scanometric assays coupled with test-strip paper-based 2D nanosheets of 1. Also, 1 can be utilized for a colorimetric luminescent thermometer in the ranges of physiological and high temperature with good linearity and recyclability.

Crystal structure of a novel one-dimensional zigzag chain-like cobalt(II) coordination polymer constructed from 4,4'-bi-pyridine and 2-hy-droxy-benzoate ligands.

A novel one-dimensional zigzag chain-like CoII coordination polymer constructed from 4,4'-bi-pyridine (4,4'-bpy) and 2-hy-droxy-benzoate (2-OHbenz) ligands, namely, catena-poly[[(4,4'-bi-pyridine-κN)-(µ-2-hy-droxy-benzoato-κ2 O:O')(2-hy-droxy-benzoato-κ2 O,O')cobalt(II)]-µ-4,4'-bi-pyridine-κ2 N:N'-[aquahemi(µ-4,4'-bi-pyridine-κ2 N:N')(2-hy-droxy-benzoato-κO(2-hy-droxy-benzoato-κ2 O:O')cobalt(II)], [Co2(C7H5O3)4(C10H8N2)2.5(H2O)] n , has been synthesized by reacting cobalt(II) nitrate trihydrate, 4,4'-bpy and 2-hy-droxy-benzoic acid in a mixture of water and methanol at room temperature. There are two independent CoII centers, Co1 and Co2, in the asymmetric unit, revealing a distorted octa-hedral geometry with chromophore types of [CoN2O4] and [CoN2O3O'], respectively. The Co1 ions are doubly bridged by 2-OHbenz ligands with syn-anti coordination mode, generating a dinuclear unit. The bridging 4,4'-bpy ligands connect these dinuclear units and the mononuclear Co2 chromophores, providing a one-dimensional alternating zigzag chain-like structure. In the crystal, inter-molecular hydrogen bonds, C-H⋯π and π-π stacking inter-actions are observed and these help to consolidate the packing. In addition, the physical properties of the title compound are reported.

Sonochemical Synthesis of Carbon Dots/Lanthanoid MOFs Hybrids for White Light-Emitting Diodes with High Color Rendering.

Although lanthanoid metal-organic frameworks (Ln-MOFs) have been widely developed for white light-emitting diodes (WLEDs), the color rendering index (CRI) values are still lower than 80. To overcome this limitation, a series of CDs/Ln-MOFs hybrids, namely, CDs-2@Ln-MOF, CDs-3@Ln-MOF, and CDs-4@Ln-MOF containing blue-emitting CDs and yellow-emitting bimetallic [(Eu1.22Tb0.78(1,4-phda)3(H2O)](H2O)2 were prepared via sonication at room temperature to restrict the self-quenching of CDs in composite materials. The as-synthesized composite materials were investigated by Fourier transform infrared, powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and photoluminescence. The luminescent color of the materials can be adjusted by varying the amount of CDs and excitation wavelengths. The resulting CDs-3@Ln-MOF achieved excellent CRI up to 93 with the ideal Commission International ed'Eclairage coordinate (0.334, 0.334) and appropriate correlated color temperature (CCT) (5443 K). In addition, the tunable multicolored luminescence based on single and bimetallic EuxTb2-x(1,4-phda)3(H2O)](H2O)2, x = 0, 0.73, 1.22, 1.57, 1.94, and 2, were applied as the luminescent security inks for anti-counterfeiting application through encoding/decoding and rewritable data.

Crystal structure and photoluminescence properties of catena-poly[[bis-(1-benzyl-1H-imidazole-κN 3)cadmium(II)]-di-µ-azido-κ4 N 1:N 3].

The new title one-dimensional CdII coordination polymer, [Cd(C10H10N2)2(µ1,3-N3)2] n , has been synthesized and structurally characterized by single-crystal X-ray diffraction. The asymmetric unit consists of a CdII ion, one azide and one 1-benzyl-imidazole (bzi) ligand. The CdII ion is located on an inversion centre and is surrounded in a distorted octa-hedral coordination sphere by six N atoms from four symmetry-related azide ligands and two symmetry-related bzi ligands. The CdII ions are linked by double azide bridging ligands within a µ1,3-N3 end-to-end (EE) coordination mode, leading to a one-dimensional linear structure extending parallel to [100]. The supra-molecular framework is stabilized by the presence of weak C-H⋯N inter-actions, π-π stacking [centroid-to-centroid distance of 3.832 (2) Å] and C-H⋯π inter-actions between neighbouring chains.

A new luminescent anionic metal-organic framework based on heterometallic zinc(II)-barium(II) for selective detection of Fe3+ and Cu2+ ions in aqueous solution.

Over the past two decades, the development of novel inorganic-organic hybrid porous crystalline materials or metal-organic frameworks (MOFs) using crystal engineering has provoked significant interest due to their potential applications as functional materials. In this context, luminescent MOFs as fluorescence sensors have recently received significant attention for the sensing of ionic species and small molecules. In this work, a new luminescent heterometallic zinc(II)-barium(II)-based anionic metal-organic framework, namely poly[imidazolium [triaqua(µ6-benzene-1,3,5-tricarboxylato)bariumtrizinc] tetrahydrate], {(C3H4N2)[BaZn3(C9H3O6)3(H2O)3]·4H2O}n (1), was synthesized under hydrothermal conditions and characterized. Compound 1 presents a three-dimensional framework with an unprecedented (3,5)-connected topology of the point symbol (3.92).(33.42.5.93.10), and exhibits `turn-off' luminescence responses for the Cu2+ and Fe3+ ions in aqueous solution based on significantly different quenching mechanisms.

Crystal structure of di-aqua-tris-(benzohydrazide-κ2 N,O)(isophthalato-κO)samarium(III) nitrate.

The first benzohydrazide complex of a lanthanide is reported. In the title compound, [Sm(C8H4O4)(C7H8N2O)3(H2O)2]NO3, systematic name di-aqua-tris-(benzohydrazide-κ2 N,O)(isophthalato-κO)samarium(III) nitrate, the SmIII ion is nine-coordinated in a distorted tricapped trigonal-prismatic geometry by three oxygen atoms and three nitro-gen atoms from three benzhydrazide (bzz) ligands, one oxygen atom from the isophthalate (itp2-) ligand, and two oxygen atoms from coordinated water mol-ecules. The nitrate group is disordered over two sets of sites with occupancy factors of 0.310 (17) and 0.690 (17). In the crystal, adjacent mol-ecules are linked into chains via pairs of O-H⋯O and N-H⋯O hydrogen bonds between the carboxyl-ate acceptor and the coordinated water and amine NH2 donors. Mol-ecules are further stacked by π-π inter-actions involving the benzene ring of the itp2- ligands, forming double chains that extend in the b-axis direction. These double chains are further linked into a three-dimensional supra-molecular network via hydrogen bonds (O-H⋯O, N-H⋯O and C-H⋯O) between the complex mol-ecule and the nitrate groups along with C-H⋯π and π-π inter-actions involving the benzene rings of the bzz and itp2- ligands.

Crystal structure of fac-{5-[(hexyl-aza-nium-yl)meth-yl]-2-(pyridin-2-yl)phenyl-κ2 N,C 1}bis-[2-(pyridin-2-yl)phenyl-κ2 N,C 1]iridium(III) chloride.

The asymmetric unit of the title compound, fac-[Ir(C11H8N)2(C18H24N2)]Cl or fac-[Ir(ppy)2(Hppy-NC6)]Cl, contains two [Ir(ppy)2(ppy-NC6)](H+) cations, two Cl- anions and disordered solvent. In each complex mol-ecule, the IrIII ion is coordinated by two C,N-bidentate 2-(pyridin-2-yl)phenyl ligands and one C,N-bidentate N-[4-(pyridin-2-yl)benz-yl]hexan-1-aminium ligand, leading to a distorted fac-octa-hedral coordination environment. In the crystal, the mol-ecules are linked by N-H⋯Cl, C-H⋯π and π-π inter-actions, forming a three-dimensional supra-molecular structure. The hexyl group of one mol-ecule is disordered over two orientations with a refined occupancy ratio of 0.412 (13):0.588 (13). The acetone and hexane solvent mol-ecules were found to be highly disordered and their contribution to the scattering was masked using the solvent-masking routine smtbx.mask in OLEX2 [Rees et al. (2005 ▸). Acta Cryst. D61, 1299-1301]. These solvent mol-ecules are not considered in the given chemical formula and other crystal data.

Crystal structure of (E)-N'-(3-fluoro-2-hy-droxy-benzyl-idene)isonicotinohydrazide.

In the title compound, C13H10FN3O2, the mol-ecule has an E conformation with respect to the C=N bond of the hydrazone bridge. The dihedral angle between the isonicotinoyl and fluoro-phenol moieties is 4.03 (4)°, and an intra-molecular O-H⋯N hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked by N-H⋯N and C-H⋯N hydrogen bonds, forming chains propagating along the a-axis direction. The chains are linked by C-H⋯O hydrogen bonds, resulting in the formation of layers lying parallel to the ab plane. The crystal structure also features π-π inter-actions [centroid-to-centroid distance = 3.6887 (8) Å].

A novel one-dimensional double-chain-like ZnII coordination polymer: poly[bis(1-benzyl-1H-imidazole-κN3)tris(µ-cyanido-κ2C:N)(cyanido-κC)disilver(I)zinc(II)].

One of most interesting systems of coordination polymers constructed from the first-row transition metals is the porous ZnII coordination polymer system, but the numbers of such polymers containing N-donor linkers are still limited. The title double-chain-like ZnII coordination polymer, [Ag2Zn(CN)4(C10H10N2)2]n, presents a one-dimensional linear coordination polymer structure in which ZnII ions are linked by bridging anionic dicyanidoargentate(I) units along the crystallographic b axis and each ZnII ion is additionally coordinated by a terminal dicyanidoargentate(I) unit and two terminal 1-benzyl-1H-imidazole (BZI) ligands, giving a five-coordinated ZnII ion. Interestingly, there are strong intermolecular AgI...AgI interactions between terminal and bridging dicyanidoargentate(I) units and C-H...π interactions between the phenyl rings of BZI ligands of adjacent one-dimensional linear chains, providing a one-dimensional linear double-chain-like structure. The supramolecular three-dimensional framework is stabilized by C-H...π interactions between the phenyl rings of BZI ligands and by AgI...AgI interactions between adjacent double chains. The photoluminescence properties have been studied.

Crystal structures of (E)-N'-(2-hy-droxy-5-methyl-benzyl-idene)isonicotinohydrazide and (E)-N'-(5-fluoro-2-hy-droxy-benzyl-idene)isonicotinohydrazide.

Two derivatives of the well-known iron chelator, (E)-N'-(2-hy-droxy-benzyl-idene)isonicotinohydrazide (SIH), substituted in the 5-position of the 2-hy-droxy-benzene ring by a methyl and a fluorine group viz. (E)-N'-(2-hy-droxy-5-methyl-benzyl-idene)isonicotinohydrazide, C14H13N3O2, (I), and (E)-N'-(5-fluoro-2-hy-droxy-benzyl-idene)isonicotinohydrazide, C13H10FN3O2, (II), have been prepared and characterized by single-crystal X-ray diffraction, (1)H NMR and mass spectrometry. The mol-ecules of both compounds deviate slightly from planarity [r.m.s. deviations are 0.145 and 0.110 Šfor (I) and (II), respectively] and adopt an E conformation with respect to the double bond of the hydrazone bridge. In each mol-ecule, there is an intra-molecular O-H⋯N hydrogen bond forming an S(6) ring motif. The dihedral angles between the mean planes of the isonicotinoyl ring and the cresol ring in (I) or the fluoro-phenol ring in (II) are 10.49 (6) and 9.43 (6)°, respectively. In the crystals of both compounds, zigzag chains are formed via N-H⋯N hydrogen bonds, in the [10-1] direction for (I) and [010] for (II). In (I), the chains are linked by weak C-H⋯π and π-π stacking inter-actions [centroid-to-centroid distances = 3.6783 (8) Å; inter-planar angle = 10.94 (5)°], leading to the formation of a three-dimensional supra-molecular architecture. In (II), adjacent chains are connected through C-H⋯O hydrogen bonds to form sheets parallel to (100), which enclose R 4 (4)(30) ring motifs. The sheets are linked by weak C-H⋯π and π-π [centroid-to-centroid distance = 3.7147 (8) Å; inter-planar angle = 10.94 (5)°] inter-actions, forming a three-dimensional supra-molecular architecture.