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A new 3D Cd(II) coordination polymer, {[Cd2(btc)(HL)(H2O)]·3H2O}n (1) (H2L= 3-(1H-pyrazol-4-yl)-5-(pyridin-2-yl)-1, 2, 4-triazole; H3btc = 1,3,5-benzenetricarboxylic acid), has been synthesized by ...

Cu–Zn composite oxide catalysts were prepared by a co-precipitation method and used in the anisole acetylation reaction. Through experimental study and characterization analysis, we have found that the activity of the catalysts derived from the Lewis acidity of the octahedrally coordinated Cu2+ (CuO2+) and ZnO plays an important role in promoting the dispersion of CuO2+ active sites, adjusting the surface structure and coordination of the catalysts. Due to the integration of ZnO and CuO with different degrees of dispersion, some of the tetrahedrally coordinated Cu2+ (CuT2+) species are converted to a low binding energy CuO2+ on different levels. When ZnO is completely dispersed in the CuO crystalline lattice, the amount of CuT2+ is at its lowest and catalyst activity is highest, with the conversion of anisole reaching 92.8% with a selectivity for p-methoxyacetophenone (p-MAP) of 97.0% under solvent-free conditions. More importantly, the catalyst can be reused three times without any treatment.

Two nickel (II) complexes, [Ni(Hcdcp) (H2O)3] (1) (H3cdcp = 3-(4-carboxylatephenyl)-2,6-pyridinedicarboxylic acid) and [Ni3(Hdcdcp)2(H2O)6]n (2) (H4dcdcp = 3-(2,4-dicarboxylatephenyl)-2,6-pyridinedicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis and single-crystal X-ray diffraction. For complex 1, Ni(II) ion is coordinated by three water molecules and a deprotonated H3cdcp ligand in chelate mode to form a mononuclear complex; for complex 2, three Ni(II) ions are connected into trinuclear clusters which are further linked into 2D layers by pentadentate Hdcdcp3− ligands in alternant bis-(bridging) and chelate coordination modes; the two complexes are both extend to 3D supramolecular polymers by hydrogen bonds. Thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD) are also carried out to determine their thermal stability and phase purity. Magnetic measurement for complex 2 reveals that weak antiferromagnetic interactions occur between the bridging trinuclear Ni( II ) ions.

Reactive synthesis of Ti5P3.16 crystals was firstly investigated in the Al–Ti–P–C alloy and their effective refinement on primary Si in Al–Si alloys was also revealed. It was found that the Ti5P3.16 phase was formed by the direct reaction of P atoms with TiC particles in Al melt. During the reaction process, P atoms absorbed on TiC agglomerates and initiated the gradual phase decomposition, and then the releasing Ti atoms combined surrounding P ones together to form Ti-P phase. Based on the TEM and SEM characterization, it is identified that the Ti5P3.16 phase has an hexagonal close packed crystal lattice structure and mainly displays a regular hexagonal prism morphology enclosed by six {10-10} facets and two parallel {0001} ones. Furthermore, the Al–Ti–P–C alloy containing the Ti5P3.16 particles showed an efficient refinement performance on primary Si particles for hypereutectic Al–Si alloy, whose average size was reduced from 85 μm to 12.5 μm for A390 alloy. In order to reveal the refinement mechanism, the evolution process of the Ti5P3.16 phase induced by Si atoms in the Al–Si melt was carried out, indicating that the Ti5P3.16 transformed into amounts of nano AlP particles with sizes of about 100–200 nm after added into the melt. Then, these in-situ AlP particles with fresh interfaces distributed uniformly in the melt and act as the effective heterogenous nuclei for the primary Si during the following solidification process of Al–Si melt with the decrease of the melt temperature, which leads to significantly refinement of the microstructure of A390 alloys.

NaTa1-xFexO3 (0 ≤ x ≤ 0.40) nanocubes were synthesized by a relatively low temperature hydrothermal method, using Ta2O5, FeCl3 and NaOH as the precursors. The UV–vis diffuse reflectance spectra showed that NaTa1-xFexO3 had significant visible-light-absorbing capability, and the absorption edge of NaTaO3 shifted to longer wavelength with the increase of Fe dopants. Moreover, NaTa1-xFexO3 exhibited room-temperature ferromagnetism when Fe3+ occupied Ta5+ sites in NaTaO3 crystal lattice. The ferromagnetism is mainly attributed to the superexchange interactions between doped Fe3+, rather than the contribution of oxygen vacancies caused by Fe doping. Therefore, Fe doping can simultaneously regulate the optical and magnetic properties of NaTaO3 semiconductor, which will enable its potential applications in multifunctional optical-electronics and optical-spintronics devices.

Using TiOiPr4 with a pyrazole ligand for one-pot LA polymerization improved catalytic activity compared with using TiOiPr4 only. At 60 °C, TiOiPr4 with furPz exhibited a higher catalytic activity (approximately 3-fold) than TiOiPr4. At room temperature, TiOiPr4 with BuPz exhibited a higher catalytic activity (approximately 17-fold) than TiOiPr4. High molecular mass PLA (MnGPC = 51 100, and Đ = 1.10) could be produced by using TiOiPr4 with furPz in melt polymerization ([TiOiPr4] : [furPz] = 1000 : 1 : 1 at 100 °C, 240 min). The crystal structure of MePz2Ti2OiPr7 revealed the cooperative activation between two Ti atoms during LA polymerization.

This work attempts to develop a multiphase field model to study ZrCoHy, ZrH2, and ZrCo2 phase formation paths in the ZrCoH0.5 matrix. Interestingly, one conserved phase-field variable (c) and four non-conserved phase-field variables (ϕi) are utilized to construct free energy function, where c represents the hydrogen concentration and ϕi stands for the ZrCoHx, ZrCoHy, ZrH2, and ZrCo2 phase. Some valuable material parameters, such as the Gibbs formation enthalpy, are also taken into account. Importantly, the system energy fluctuation is taken as the driving force of phase evolution, and then, governing equations are solved by self-programming complied with the Fortran language. The results demonstrate that disproportionation products are most likely to be derived from the initial ZrCoHy. The presence of ZrH2 and ZrCo2 promotes the nucleation incubation of disproportionation products. Besides, ZrCoHy is more prone to generate ZrH2 and ZrCo2 in comparison with ZrCoHx, which is attributed to the fact that the crystal structure of ZrCoHy is closer to that of ZrCo2. Because ZrCoHy could be regarded as the transition state when ZrCoHx is transformed into ZrCo2, ZrCoHy is easy to be produced in advance during the ZrCoHx disproportionation process, instead of ZrH2 and ZrCo2 directly generated by the ZrCoHx disproportionation.

A novel complex [CoII(L)2·CH3OH] with hydrazone derived from protocatechuic acid (HL=C16H14N2O4) is designed and synthesized. The complex is characterized by single crystal X-ray diffraction, elemental analysis, IR, and thermal gravimetric analysis. The complex crystallizes in the monoclinic space group C2/c, with unit cell dimensions a = 25.1715(11), b = 9.3518(4), c = 12.8700(6) A, β = 103.6530(10)°, V = 2943.98(75) A3, Z = 4, R1 = 0.0612, and wR2 = 0.1439.

C26H21N6O6.5Zn, monoclinic, C2/c (no. 15), a = 18.3123(3) Å, b = 8.97463(15) Å, c = 30.1437(5) Å, β = 99.5396(16)°, V = 4885.51(14) Å3, Z = 4, R gt(F) = 0.0352, wR ref(F 2) = 0.0746, T = 293(2) K.

Three structurally related ligands 3-chloro-6-(benzoimidazol-1-yl)pyridazine (L 1 ), 3-chloro-6-(1,2,4-triazol-1-yl)pyridazine (L 2 ) and 3,6-bis(imidazol-1-yl)pyridazine (L 3 ) were designed and synthesized, and six new Zn(II), Co(II), Cu(II) and Cd(II) complexes, namely, [M(L 1 )2Cl2] [M = Zn (1) and Co (2)], [Cu(L 2 )2(NO3)2(H2O)] (3), [Cu(L 2 )2Cl2]∞ (4), [CuL 3 (CH3COO)2]∞ (5) and [CdL 3 (SCN)2]∞ (6) were synthesized and characterized by elemental analyses, IR spectra as well as single-crystal X-ray diffraction analysis. The analysis reveals that complexes 1, 2 and 3 have a mononuclear structure, 1 and 2 have a similar structure. Complex 3 features a 1D structure with intermolecular O–H⋯O hydrogen bonding interactions. Complex 4 shows a 1D chain structure with bridging Clˉ ions. Complex 5 exhibits a 1D ladder structure. The 2D framework of 6 features are rectangular grid with a (4, 4) topology. Additionally, photoluminescence properties of ligands L 1 , L 3 and complexes 1, 2 and 6 have been studied and discussed. Six new metal-organic complexes were synthesized and structurally characterized, complexes 1, 2 and 3 have a mononuclear structure, complexes 4 and 5 show 1D chain structure, the 2D framework of 6 has a rectangle grid with a (4, 4) topology, moreover, photoluminescence properties of ligands L 1 , L 3 and complexes 1, 2 and 6 have been studied and discussed.

We studied and compared the photophysical and aggregation-induced emission properties of three isomers: trans-1,2-di(9-anthryl)ethylene (DAE), trans-1-(9-anthryl)-2-(9-phenanthryl)ethylene (APE), and trans-1,2-di(9-phenanthryl)ethylene (DPE). Both DAE and APE molecules have a twisted conformation due to intramolecular H···H steric hindrance. By contrast, this kind of steric hindrance drastically decreases in DPE molecule. From DAE, APE, to DPE, there are a blue shift in the optical spectra and a marked increase in the fluorescence efficiency. Mainly due to the restriction of intramolecular rotation, DAE displays an aggregation-induced emission behavior. However, the fluorescence efficiency of APE decreases from solution to solid state. Different from DAE and APE, DPE is a dual-state highly-efficient chromophore. The fluorescence efficiencies of its solution and the as-prepared powder (DPE-α) are 60% and 81%, respectively. J-aggregate was observed in the crystal structure of DPE-α, which correlates with its high emission efficiency. Interestingly, a new metastable polymorph of DPE was unexpectedly obtained by a solvent-antisolvent rapid precipitation. This new polymorph displays vapour- and temperature-induced crystal-to-crystal phase transition and fluorochromism.

A new caffeic acid derivative ((E)-3-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)acrylic acid, HL1)) is synthesized from caffeic acid, followed by the preparation of a Cu(II) complex, [Cu2(L1)4DMSO2]·2DMSO. The structure is determined by single crystal X-ray diffraction, and the urease inhibitory activity of the complex is studied. The results show that IC50 of the complex is 0.56 μmol/L, which is superior to positive control acetohydroxamic acid (AHA, IC50 was 10.95 μmol/l), i.e., the complex has strong inhibitory activity towards urease.

In this paper, a series of new complexes, [Zn2(HL1)2(H2O)4]·H2O (1), [Co2(HL1)2]·TEA (2), [Co3(HL1)2(H2L1)2(H2O)4]n (3), [Cu(HL1)(H2O)2]n (4), {[Cu5(HL2)2(OH)4(ClO4)2]·4H2O}n (5) and [Cu2(L3)]n (6) were successfully prepared by utilizing three bis(tetrazole) ligands [bis-(1H-tetrazol-5-ylmethyl)-amine (H3L1), bis-(1H-tetrazol-5-ylethyl)-amine (H3L2) and 1,5-bis(5-tetrazolo)-3-thiapentane (H2L3)], all of which have been characterized by elemental analyses, FT-IR spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analyses as well as single-crystal X-ray diffraction analyses showing different dimensionalities (0D, 1D and 3D). Complexes 1 and 2 are 0D structures, 1 shows a dinuclear structure, 2 displays two crystallographically different mononuclear structures, 1 and 2 are further assembled to form 3D supramolecular framework and 2D supramolecular network by hydrogen-bonding interactions, respectively. Complexes 3, 4 and 5 are 1D structures, 3 features a mononuclear unit and a 1D chain, which are arranged into 3D supramolecular architecture by hydrogen-bonding interactions, 4 presents a zigzag chain, 5 shows an infinite chain structure constructed from pentanuclear Cu(II) subunits and ClO4− anions. Complex 6 exhibits a 3D coordination framework based on cyclic [Cu4(L3)2] dimmer subunits as nodes possessing an 8-connected network topology with the point symbol {424·64}. Further, semiconductor behaviors, the solid-state luminescent properties of the complexes 1–3 and 6 were measured and studied seriously at room temperature.

The cyclin dependent kinase CDK8, along with Med12 and Med13, form the kinase module of the Mediator complex. CDK8 expression associates with the activation of β-catenin in colon and gastric cancers. Herein, we applied docking-based virtual screening (VS) using the multiple crystal structures to identify several potent CDK8 inhibitors. The appropriate use of multiple crystal structures obtained a better enrichment of CDK8 conformations to cope with the protein flexibility. Later on, the 2D similarity search was used to find the derivatives of the high inhibitory CDK8 inhibitors we discovered by VS. Finally, we measured the dose response behaviors, the IC50 values of compound W-34, W-37, W-8, WS-2 are 6.5 nM, 36 nM, 93 nM, 9 nM, respectively. These novel leads provided good starting points to design and synthesis a series of highly selective and potent CDK8 inhibitors.

In this paper, we synthesized mixed-cation [HC(NH2)2]x[CH3NH3]1−xPbI3 (FAxMA1−xPbI3) (x = 0.8, 0.6, 0.4, 0.2) perovskite nanostructures through a simple solution method. The morphology and crystal structure of the FAxMA1−xPbI3 nanostructures are measured by field emission scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). The temperature-dependent photoluminescence (PL) of FAxMA1−xPbI3 nanostructures is investigated; the integrated PL intensity exhibits an exponential decrease with the increase of temperature. An abnormal redshift of the center PL emission wavelength due to orthorhombic–tetragonal phase transition in the transitional temperature region around 150 K is observed from the temperature-dependent PL; the center PL emission wavelength shows continuous blue-shift in the pure orthorhombic phase and tetragonal phase. In addition, the exciton binding energy of FAxMA1−xPbI3 nanostructures was obtained by analysing the PL intensity decay. The exciton binding energy decreases when the FA/MA ratio approaches 1 : 1. The low Urbach energy of ∼25 meV was fitted from the absorption spectra. These results on optical properties indicate the advantage of FAxMA1−xPbI3 in solar cell devices.

Nine new complexes, {[Zn3(L1)2(OH)2]·H2O}n (1), [Ag2(L1)]n (2), {[Co(HL1)2(H2O)4]·2H2O} (3), [Cu3(L1)2(OH)2(H2O)]n (4), {[Cu7(HL1)2(L1)6(H2O)6]·11.1H2O}n (5), {[Cu(L1)(H2O)3]·8H2O}n (6), [Ag2(L2)]n (7), [Ag8(L3)4(H2O)]n (8) and [Cu(L3)(H2O)2]n (9) [H2L1 = 2,6-dinitro-4-(1H-tetrazol-5-yl)phenol, H2L2 = 2,4,6-trinitro-3-(1H-tetrazol-5-yl)phenol, H2L3 = 2,4-dinitro-6-(1H-tetrazol-5-yl)phenol], have been solvothermally synthesized via in situ nitration from 4-(1H-tetrazol-5-yl)phenol, 3-(1H-tetrazol-5-yl)phenol and 2-(1H-tetrazol-5-yl)phenol precursors as well as nitrate salts as nitration reagents and structurally characterized by single-crystal X-ray diffraction, infrared spectroscopy (IR), elemental analysis, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). The structures of the complexes vary from 3D frameworks for 1, 4 and 7, 2D networks for 2, 5 and 8, 1D chains for 6 and 9, to a discrete 0D structure for 3, showing 2D supramolecular structures by interlayer π–π stacking. Topological classification of 2D and 3D architectures was performed, disclosing a variety of topological symbols: (42·6)2(44·62·88·10) for 1, (43)2(46·66·83) for 2, (46)2(412·612·84) for 4, (63) for 5 and (45·6)(47·63)(418·616·82) for 7. The contrast of 1–9 reveals that ligands and metal salts have important influences on adjusting the crystal structures; notably, the coordination modes of the ligands can also tune the structures of 4–6 which possess the same ligands and nitration agents. The solid-state UV-vis spectra and band gap energy of the nine complexes were investigated. In addition, the luminescence properties (for complexes 1–3, 7 and 8) and magnetic properties (for complexes 3–6 and 9) were also discussed.

Herein we reported six new Ni(II)/Cu(II)/Zn(II) complexes, namely, [Ni(L1)4(OH)2] (1), [Cu(L1)4(OH)2] (2), [Cu(L1)2(SiF6)]n (3), {[Cu(L2)(HCOO)2]·H2O·CH3OH}n (4), [Ni(L2)2(NO3)2]n (5) and {[Zn(L2)Cl2]·DMF}n (6) (L1 = 3,6-bis(imidazole-1-yl)pyridazine, L2 = 3,6-bis(benzimidazole-1-yl)pyridazine), which were characterized by single-crystal X-ray diffraction, elemental analysis, IR, PXRD. These complexes have been successfully constructed under interface diffusion process, heating reflux or hydrothermal conditions. The structures of 1 and 2 are mononuclear complexes. Complex 3 exhibits a 6-connected 3D topology network with the Schlafli symbol of (412·63). In complex 4, two Cu(II) were connected through two HCOO− anions to form dinuclear structure unit, which is arranged into a 1D ladder-like structure by μ2-L2 ligands. Complexes 5 and 6 are 1D zigzag chains connected by L2 ligands, but the Ni(II) ion is six-coordinated in 5 and the Zn(II) ion is four-coordinated in 6. Moreover, the solid-state luminescence property and UV–vis diffuse reflection spectrum of complex 6 have been investigated and discussed.

C32H28N4O5Mn, monoclinic, P21/c (no. 14), a = 8.777(3) Å, b = 30.975(11) Å, c = 10.229(4) Å, β = 105.412(7)°, V = 2680.9(16) Å3, Z = 4, R gt(F) = 0.0448, wR ref(F 2) = 0.1136, T = 296(2) K.

C36H44N8NiO12, triclinic, P1̅ (no. 2), a = 10.6451(5) Å, b = 12.1086(6) Å, c = 17.2600(7) Å, α = 76.624(4)°, β = 72.200(4)°, γ = 70.802(5)°, V = 1979.18(18) Å3, Z = 2, R gt(F) = 0.0414, wR ref(F 2) = 0.1058, T = 293(2) K.

A new Zinc(II) coordination polymer, {[Zn(ip)(H2L)]·4H2O}n [H2ip = isophthalic acid; H2L = 3-(1H-pyrazol-4-yl)-5-(pyridin-2-yl)-1,2,4-triazole], is reported here. It has been structurally characterized by X-ray single crystal analysis, IR spectra, fluorescence spectroscopy, thermogravimetry analysis and X-ray powder diffraction patterns. It belongs to the triclinic system, space group P-1 with a = 8.7934(3) Å, b = 10.1639(3) Å, c = 12.3203(5) Å, α = 75.174(3)°, β = 81.739(3)°, γ = 79.578(4)°, V = 1041.40(7) Å3, Z = 2, Dc = 1.638 g/cm3, Mr = 513.77, F(000) = 528, R = 0.0344 and wR = 0.0798. The single X-ray diffraction studies reveal that the compound exhibits 2D layer structure. Moreover, thermal behavior and luminescence properties of the compound were also studied.

In this work, a series of dinuclear Ln(III)-based compounds with the molecular form [Ln2(L)2(dbm)2(H2O)2]·nCH3OH (Ln(III) = Eu (1), Gd (2), Tb (3), Dy (4) and Ho (5), Hdbm = 1,3-diphenyl-1,3-propanedione and H2L = 2-[(1E)-{[(pyridin-2-yl)formamido]imino}methyl]benzoic acid) have been successfully synthesized using a polydentate Schiff base ligand (H2L) and reacting it with the β-diketone salts Ln(dbm)3·2H2O. The crystal structures and magnetic properties of the five Ln2 compounds have been completely studied. The crystal structure studies reveal that compounds 1–5 are isostructural and show a dinuclear structure with a parallelogram Ln2O2 core. The magnetic research suggests that the Gd2 compound shows a cryogenic magnetic refrigeration property with magnetic entropy (−ΔSm) = 23.2 J K−1 kg−1 (T = 2.0 K and ΔH = 7.0 T), while the Dy2 compound exhibits slow magnetic relaxation behavior.

A novel ytterbium metal–organic framework based on an unprecedented [Yb6(μ2-OH)2(μ3-OH)6]10 + cluster has been obtained and characterized, which shows a rare (3,12)-connected {32.4}2{38.422.524.610.72} topological net and strong near-infrared luminescent emission.

A new Schiff base compound 4-methyl-2-(naphthalen-1-yliminomethyl)phenol (HL; 1) and its mononuclear cobalt(III) complex, [Co(L2)(MeSal)] (2) (MeSal = 2-formyl-4-methylphenolate), have been prepared and characterized by elemental analysis, IR and UV-Vis spectra, and single-cyrstal X-ray diffraction. Compound 1 crystallizes in the monoclinic space group P21/c with unit cell dimensions a = 7.724(1), b = 12.735(2), c = 28.877(3) A, β = 90.026(2)°, V = 2840.3(7) A3, Z = 8, R1 = 0.0615, and wR2 = 0.1021. Complex 2 crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 27.264(2), b = 10.794(1), c = 26.954(2) A, β = 116.522(2)°, V = 7097.5(9) A3, Z = 8, R1 = 0.0554, and wR2 = 0.1134. The Schiff base ligand coordinates to the Co atom through the phenolate O and imino N atoms. The Co atom in the complex is in an octahedral coordination. Crystals of the compounds are stabilized by hydrogen bonds and π···π interactions.

A dicyanoamide-bridged polymeric copper(I/II) complex, [CuII(sal)(bipy)CuI(dca)2]n, was prepared by reaction of 5-methylchlorosalicylaldehyde (Hsal), 2,2′-bipyridine (bipy), sodium dicyanoamide (Nadca), and copper perchlorate in methanol. The complex was characterized by elemental analyses, infrared and electronic spectroscopy, and single-crystal X-ray determination. CuII has a square pyramidal coordination, and CuI has triangular coordination. The complex showed high urease inhibitory activity with IC50 value of 0.16 ± 0.23 μM.

Three new coordination polymers, namely, {[Ni(H2L)(bix)(H2O)2]·2h2O}n (1), {[Ni(HL)(Hdpa)(H2O)2]·H2O}n (2), {[Ni(L)0.5(bpp)(H2O)]·H2O}n (3) (H4L=terphenyl-2,2′,4,4′-tetracarboxylic acid; bix=1,4-bis(imidazol-1-ylmethyl)benzene; dpa =4,4′-dipyridylamine; bpp=1,3-bis(4-pyridyl)propane), based on rigid H4L ligand and different N-donor co-ligands, have been synthesized under hydrothermal conditions. Compound 1 features a 3D 4-connected 66-dia-type framework with H4L ligand adopts a μ2-bridging mode with two symmetry-related carboxylate groups in μ1-η1:η0 monodentate mode. Compound 2 displays a 1D [Ni(HL)(Hdpa)]n ribbon chains motif, in which the H4L ligand adopts a μ2-bridging mode with two carboxylate groups in μ1-η1:η1 and μ1-η1:η0 monodentate modes, while 3 possesses a (4,4)-connected 3D frameworks with bbf topology, with H4L ligand displays a μ4-bridging coordination mode. The H4L ligand displays not only different deprotonated forms but also diverse coordination modes and conformations. The structural diversities among 1–3 have been carefully discussed, and the roles of N-donor co-ligands in the self-assembly of coordination polymers have been well documented.

In this paper we try to tailor the chemical stability of cobalt-rich perovskite Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3 − δ (BSCF) by B-site doping Sb. The chemical stability of Ba 0.5 Sr 0.5 Co 0.8 Fe 0.1 Sb 0.1 O 3 − δ (BSCFS) was investigated by studying the oxygen nonstoichiometry, crystal structure and oxidation state by means of coulometric titration, high-temperature X-ray diffraction (HT-XRD) and soft-X-ray absorption spectroscopy (s-XAS) in various oxygen pressure ( p (O 2 )) and temperatures. The results prove that chemical stability of BSCFS is successfully improved in intermediate temperature solid oxide fuel cell working condition owing to Co valence change which is controlled by high valence cation doping.

Magnetic and electronic properties of S- and N-doped CrO 2 are studied by using the first-principle projector augmented wave potential within the generalized gradient approximation. The optimized lattice constants for CrO 2 agree well with the previous work. With increasing S doping (N doping), the lattice constants of CrO 2− x S x (CrO 2− x N x ) ( x =0.5, 1 and 1.5) all increase (decrease), While these compounds remain the tetragonal structure. CrO 1.5 S 0.5 , CrO 1.5 N 0.5 and CrON compounds remain the half-metallicity, while the band gap is determined by different factors. It is also found that the change of the total magnetic moment with equivalent atom S doping in CrO 2 compound is small except for x =1.

A series of new cobalt(III) complexes were prepared. They are [CoL(1)(py)3]·NO3 (1), [CoL(2)(bipy)(N3)]·CH3OH (2), [CoL(3)(HL(3))(N3)]·NO3 (3), and [CoL(4)(MeOH)(N3)] (4), where L(1), L(2), L(3) and L(4) are the deprotonated form of N'-(2-hydroxy-5-methoxybenzylidene)-3-methylbenzohydrazide, N'-(2-hydroxybenzylidene)-3-hydroxylbenzohydrazide, 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol, and N,N'-bis(5-methylsalicylidene)-o-phenylenediamine, respectively, py is pyridine, and bipy is 2,2'-bipyridine. The complexes were characterized by infrared and UV-Vis spectra, and single crystal X-ray diffraction. The Co atoms in the complexes are in octahedral coordination. Complexes 1 and 4 show effective urease inhibitory activities, with IC50 values of 4.27 and 0.35 μmol L(-1), respectively. Complex 2 has medium activity against urease, with IC50 value of 68.7 μmol L(-1). While complex 3 has no activity against urease. Molecular docking study of the complexes with Helicobacter pylori urease was performed.

An ether bridged tetracarboxylic acid ligand, 5-(3′,4′-Dicarboxylphenoxy)-isophthalic acid (H4L) was used to construct two Co(II) coordination polymers in presence of different nitrogen donor ligands such as 4,4′-bipyridine (4,4′-bpy) and 4,4′-bis(pyrid-4-yl)biphenyl (bpbp). The products formed under hydrothermal conditions are formulated as [Co2L(4,4′-bpy)2(H2O)3]n (1) and {[Co(bpbp)2(H2L)]·H2O}n (2). The compounds were characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis, and powder X-ray diffraction (PXRD) measurement. Compound 1 shows an intriguing (3,4,5)-connected 3D framework with a point symbol of (42 · 62 · 82)(42 · 65 · 83)(62 · 8). Compound 2 is an unusual 3D supramolecular framework generated by the one-dimensional [Co(bpbp)(H2L)]n polymer chain. The magnetic properties of compounds 1 and 2 were examined, indicating antiferromagnetic interactions between the cobalt(II) ions in the temperature range of 2–300 K.

A new Co(II) coordination polymer, namely [Co6(btc)4(dtb)2(H2O)3]n (1) (H3btc = 1,3,5-benzenetricarboxylic acid, dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene), has been synthesized by combining the mixed ligands of H3btc and dtb with Co(Ac)2·4H2O under solvothermal conditions. Single-crystal X-ray diffraction analysis reveals that 1 feature a 3D open framework with intersecting channels based on Co-btc3 − layers and btc3 − and dtb pillars. The magnetic property of the complex has also been investigated at room temperature.

We describe the design, synthesis and biological evaluation of a series of novel HIV-1 protease inhibitors bearing isophthalamide derivatives as the P2–P3 ligands. We have investigated a range of acyclic and heterocyclic amides as the extended P2–P3 ligands. These inhibitors displayed good to excellent HIV-1 protease inhibitory activity. Also, a number of inhibitors showed very good antiviral activity in MT cells. Compound 5n has shown an enzyme Ki of 0.17 nM and antiviral IC50 of 14 nM. An X-ray crystal structure of inhibitor 5o-bound to HIV-1 protease was determined at 1.11 A resolution. This structure revealed important molecular insight into the inhibitor–HIV-1 protease interactions in the active site.

Herein, we suggest a unique approach to control the handedness of twisted lamellae in banded spherulites of a stereoregular polymer, isotactic poly(2-vinylpyridine) (iP2VP). When (R)- or (S)-hexahydromandelic acid (HMA), which can associate with iP2VP, was introduced as a chiral dopant, mirror-image CD spectra in the complex systems showed induced circular dichroism (ICD) of the iP2VP by chiral HMA. Banded spherulites resulting from lamellar twisting due to the imbalanced stresses at the opposite folding surfaces could be formed by crystallization of the iP2VP/HMA complexes, which had a crystalline structure similar to that of neat iP2VP. A preferential sense of the twisted crystalline lamellae was found in the iP2VP/HMA complex, thus suggesting homochiral evolution from conformational to hierarchical chirality.

Structural, magnetic and electronic properties of C-doped monoclinic ZrO2 have been studied by using the first principles projector augmented wave potential within the generalized gradient approximation as well as taking into account on site Coulomb repulsive interaction. The optimized structures show the lattice constants a, b, c and monoclinic angle β of C-doped monoclinic ZrO2 change slightly. While the lattice constants a, b, c and monoclinic angle β of C1-doped monoclinic ZrO2 are smaller than that of C2-doped monoclinic ZrO2. The total magnetic moment of C-doped monoclinic ZrO2 is mainly contributed by the atomic magnetic moment of C atom. For C atom substituting O atom, the systems are found to be half-metallic material and usable in magnetoelectronic and spintronic devices.

A new Cu(II) metal-organic framework {[Cu1.5(1,3-bdc)(dtb)(OH)(H2O)](H2O)}n (1) (1,3-H2bdc = 1,3-benzenedicarboxylic acid, dtb = 1,3-di-(1,2,4-triazole-4-yl)benzene), has been synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, and IR spectra. Compound 1 features a 3-D open framework constructed by infinite 1D rod-shaped [Cu3(OH)2]n chains as secondary building units. The magnetic property of the complex has also been investigated.

Bi2O3 nanospheres co-doped with Yb3+/Er3+ upconverting ions pair have been successfully synthesized via a facile hydrothermal method followed by a heat treatment. The resulting Bi2O3:Yb3+,Er3+ nanospheres show a monodisperse spherical morphology with narrow size distribution (~180 nm) and display intense upconversion luminescence under 980 nm laser excitation. It is found that the crystal structure, morphology and upconversion luminescence properties of nanospheres have a direct relationship with the doping concentration of Yb3+ and the subsequent calcination temperature. These Bi2O3:Yb3+,Er3+ nanospheres can be prepared in large quantities and can be easily modified with a layer of biocompatible polyethyleneimine (PEI) molecules. The yielded nanospheres could not only maintain uniform size and morphological characteristics, but also show good water dispersibility and biocompatibility. Remarkably, these Bi2O3:Yb3+,Er3+ upconversion nanophosphors could also act as an effective contrast agent for X-ray computed tomography (CT) imaging, which show higher contrast efficacy than commercial iodine-based contrast agent. The proposed facile synthetic route and inexpensive matrix materials pave the way for broad use of these Bi2O3:Yb3+,Er3+ nanospheres as ideal dual-mode bioimaging probes in biomedical field.

A novel hexavanadate-based derivative covalently modified with glycine ethyl ester has been successfully synthesized via step-by-step functionalization. FT-IR, UV/visible, 1H NMR, ESI-MS spectrogram and single crystal X-ray diffraction were applied to certify the structure of the new compound. Moreover, this hybrid exhibited stronger inhibitory activity on human hepatocellular carcinoma tumor cells than the hexavanadate platform and even the universal commercial drug 5-fluorouracil. This work shows a broad prospect in the biochemical applications of polyoxovanadate-amino acid hybrids.

New [1+1] and 62-membered [2+2] Schiff base macrocycles containing a 2,6-diamidopyridine subunit have been synthesized by condensation reaction of the precursors pyridine-2,6-dicarboxamide and 1,10-bis(2′-formylphenyloxy)decane in the presence of phosphoric acid via a one-pot process. The cyclo-condensed products were effectively isolated by gel column chromatography and characterized by 1H NMR, FTIR, mass spectrometry and X-ray analysis. The two macrocycles have a twisted structure, and not an open ‘circular’ conformation in the solid state.

1H NMR spectroscopy and MALDI-TOF mass spectrometry were utilized to examine the binding interaction of α,α′,δ,δ′-tetramethylcucurbit[6]uril (TMeQ[6]) and six biogenic amines (spermine, spermidine, 2-phenethylamine, tyramine, histamine, and tryptamine). Their 1H NMR spectra both at pD = 7 and pD = 3 revealed that four biogenic amines (spermine, spermidine, 2-phenethylamine, and histamine) can fit in the TMeQ[6] cavity, respectively, and other biogenic amines were located outside of the TMeQ[6] portal. In addition, a solid-state evaluation with single-crystal X-ray diffraction analysis showed the binding interaction of spermine, spermidine, 2-phenethylamine, and tyramine with TMeQ[6].

INTRODUCTION. The structures of members of the Tcl1 oncoprotein family are being studied in order to understand their roles in lymphocyte biology and their development of lymphocytic diseases[1-3]. These ~15 kD proteins share 25–80% sequence identity between the members of the family. No sequence similarity was found with other human genes suggesting a unique cellular role(s). Family members share an uncommon tertiary structure of an eight-stranded beta barrel. Recently, the crystal structure of murine Tcl1 was determined[3]. The three structures were analyzed to reveal conserved features indicative of a potential binding site for an interacting protein.

Using the first principle projector augmented wave potential within the generalized gradient approximation as well as taking into account the on-site Coulomb repulsive interaction, the structure, magnetic and electronic properties of N-doped monoclinic ZrO2 have been studied. For N doping in different oxygen sites, the lattice constants a, b, c and monoclinic β angle are almost equal. The N-doped m-ZrO2 is a ferromagnetic half-metallic material. The total magnetic moment is mostly contributed by the N atom. Spin splitting occurs between the partial DOS of the up-spin and down-spin channels for N 2s and 2p states, as well as the hybridization appears between N 2p and O 2p states. The strong ionic bonding character in N-doped m-ZrO2 is revealed in the substantial charges transfer from Zr atoms to N and O atoms.

Hydrothermal reactions of biphenyl-2,3,3′,5′-tetracarboxylic acid (H4bptc) with manganese salt in the presence of 1,4-bis(2-pyridylmethyl)piperazine (bpmp) afforded one novel coordination polymer, namely, [Mn2(bptc)(bpmp)0.5]n (1). Its structure was established by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analysis. Complex 1 contains {Mn4} cluster, exhibiting an unusual mode of two-fold interpenetrating three-dimensional (3D) framework with a (3, 8)-connected (84.102) (4.7.84.102.11.15) topology. In addition, magnetic susceptibility measurements indicate that complex 1 show weak antiferromagnetic interactions between the adjacent manganese ions.

A cadmium(II) complex containing an octacarboxylate ligand (L), Cd2(C42H22O20)·5(H2O)·4(CH3NH2CH3), has been solvothermally synthesized and characterized by elemental analysis, spectroscopic studies (IR spectrum, diffuse reflectance spectrum, and solid-state emission spectrum), powder X-ray diffraction, and single-crystal X-ray diffraction. In 1, Cd1 is coordinated by four carboxylates from four different L and L is coordinated to eight Cd ions with its eight carboxylates. Compound 1 possesses a porous 3-D framework with total solvent-accessible volume of 1800.7 A3 per unit cell, comprising 52.7% of the total crystal volume.