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An unusual distorted noninterpenetrated utp net based on Zn coordination with the mixed ligands of 1,3,5-benzenetricarboxylate (BTC) and 1,3-bis(4-pyridyl)propane (BPP) is defined. The results demonstrate that the template effect of the auxiliary ligand plays an important role in the construction of novel topological nets.

A study is conducted which successfully synthesized a novel photoluminescent 3-D polymeric complex based on decnuclear copper(I) clusters. The development of a new strategy to construct diverse polymeric copper(I) complexes through an in situ solvothermal redox reaction provides a new method for transforming organic sulfur into inorganic sulfate.

A new approach to cisplatin storage and release using porous hollow nanoparticles (PHNPs) of [Fe.sub.3][O.sub.4] is reported. The model experimental results indicated that the low pH-responsive PHNPs of [Fe.sub.3][O.sub.4] could be exploited as a cisplatin delivery vehicle for target-specific therapeutic applications.

The development of a palladium-catalyzed direct arylation of indoles with potassium aryltrifluoroborates combined with copper as a cocatalyst using air as the oxidant is reported. The reaction was significantly enhanced by the addition of 10 mol% Cu[(OAc).sub.2].

Two three-dimensional (3D) Zn(II) and Pb(II) isophthalates are prepared under hydro(solvo)thermal conditions and characterized by single-crystal X-ray diffraction. Density functional theory method is used for studying the optical properties, thermal stabilities, band structure and density of states of these complexes.

The hydrothermal reactions of guanazole with suitable cadmium salts under appropriate reaction conditions were used to synthesize several new anion-controlled Cd(II)-guanazole (3,5-diamino-1,2,4-triazole = Hdatrz) hybrid family. Most of the compounds showed a high thermal stability, while most of them are almost insoluble in most common solvents.

The study describes the preparation and functionalization of porous silica particles in various mesoporous materials and the Acid-Prepared Mesoporous Spheres (APMS). The analysis shows that the diffusion-based deprotection in such materials can be easily controlled.

Two unusual coordination modes of melamine in two organic-inorganic hybrid copper halides, [[[Cu.sub.2][Br.sub.2](MA)].sub.n] and [[[Cu.sub.3][Cl.sub.3](MA)].sub.n], are described. The important N-H...X (X = Cl or Br) hydrogen bonds have directed the [[mu].sub.2]- and [[mu],sub.3]-bridging coordination of melamine, making them thermally very stable.

A method for the evaluation of palladium-catalyzed cross-coupling of aryl boronic acid with carboxylic anhydride or acyl chloride in the absence of phosphine ligands in water is reported. The straightforward method allows the palladium acetate-catalytic system to be recovered and reused eight times with high efficiency for both carboxylic anhydride and acyl chloride.

Three novel complexes with different architectures, (H2-BPTC)(4,4'-H2bpy)H2O (1), [Cd2Cu(HBPTC)2(u2-4,4'-bpy)2-(4,4'-bpy)2(H2O)2]n (2), and [Co3(HBPTC)2(u2-4,4'-bpy)3-(H2O)4]n.2nH2O (3), were constructed with H4BPTc ligand in the presence of auxiliary 4,4'-bpy ligand. Structural determinations of the complexes demonstrate that the 3,3',4,4' -benzophenone-tetracarboxylate (BPTC) ligand has the unique ability to form strong hydrogen bonding network.

Iron titanate catalysts with variable Nb content was synthesized by the homogeneous precipitation method, and they were applied to the NH3-selective catalytic reduction (SCR). The widest performance temperature window is obtained on the 0.05Nb–0.95Fe–Ti–O catalyst between 200 and 400 °C with a NO conversion higher than 90% at a gas hourly space velocity (GHSV) of 50 000 h–1. The addition of Nb improves the acidity of Fe–Ti–O catalyst while decreasing its reducibility. The excellent performance of 0.05Nb–0.95Fe–Ti–O is attributed to its suitable acidity and reducibility. Both Brønsted and Lewis acid sites over 0.05Nb–0.95Fe–Ti–O catalyst are active in the reaction, and the formation of reactive monodentate nitrate species and cis-N2O22– also promote the performances. [ABSTRACT FROM AUTHOR]

Nature tends to assemble hierarchical structures in similar ways to achieve compactness and functions. This work probes the interior lamellae assembly of crystalline spherulites of poly(ethylene adipate) (PEA) with striking birefringence patterns versus some known biological structures for optical color diffraction. Three-dimensional dissecting onto interior lamellar structures of spherulites in poly(ethylene adipate) (PEA) in bulk forms crystallized at 28 ± 3 °C were studied in correlation with thin-film forms. Interior morphology in bulk PEA samples revealed periodic hemisphere or arc-shaped layers resembling corrugate boards with liner-flute medium alteration. Interior spherulites clearly expose that the lamellae within the intralayer are kebabs (plates) in the radial direction while the interlayer region are thin sheaths (fibrils) composed of cilia-like lamellae in the tangential direction. The interior repetitive lamellar assembly of PEA banded spherulites in displaying periodic optical birefringence patterns is proven to highly resemble those in many biological structures for iridescence light interference. [ABSTRACT FROM AUTHOR]

A luminescent polymer was synthesized through a series of rather complex procedures under salvo thermal conditions. This method is very useful for developing new methods to prepare new luminescent Cu3l4 clusters.

In this work, liquid phase compositions for mixtures of water + methanol + ethyl methyl carbonate (EMC) + heptane, water + ethanol + EMC + heptane, and water + methanol + EMC, water + ethanol + EMC, and water + EMC + heptane at 25 °C were measured at atmospheric pressure. The modified UNIQUAC activity coefficient model was employed to correlate the experimental tie-line data, and the results were compared with ones obtained with the extended UNIQUAC model. The consistency of the measured tie-line data was ascertained by applying the Othmer-Tobias equation. [ABSTRACT FROM AUTHOR]

The DEDDh family of exonucleases plays essential roles in DNA and RNA metabolism in all kingdoms of life. Several viral and human DEDDh exonucleases can serve as antiviral drug targets due to their critical roles in virus replication. Here using RNase T and CRN-4 as the model systems, we identify potential inhibitors for DEDDh exonucleases. We further show that two of the inhibitors, ATA and PV6R, indeed inhibit the exonuclease activity of the viral protein NP exonuclease of Lassa fever virus in vitro. Moreover, we determine the crystal structure of CRN-4 in complex with MES that reveals a unique inhibition mechanism by inducing the general base His179 to shift out of the active site. Our results not only provide the structural basis for the inhibition mechanism but also suggest potential lead inhibitors for the DEDDh exonucleases that may pave the way for designing nuclease inhibitors for biochemical and biomedical applications. [ABSTRACT FROM AUTHOR]

The presence of intracellular filamentous a-synuclein (aS) aggregates is a common feature in Parkinson's disease. Recombinant expressed and purified human aS is also capable of forming fibrils in vitro. Many studies have shown that solution conditions heavily influence aS fibrillation kinetics, fibril structure, and morphology that exhibit differential biological effects. Nevertheless, the aS ensemble structure in various solution conditions is not well characterized; furthermore, how the initial solution ensemble structures impact aS assembly kinetics and pathways that result in diverse fibril structure and morphology remains elusive. Here, we mainly employed NMR spectroscopy to characterize the initial ensemble structure of aS in the presence or absence of a 150 mM sodium chloride (NaCl) solution, where two polymorphs of aS were demonstrated in previous studies. Our data show that aS exhibits distinct conformations and fibrillation kinetics in these two solutions. aS adopts a more compact and rigid ensemble structure that has faster fibrillation kinetics in the absence of NaCl. On the basis of the ensemble structure and dynamics, we proposed a possible molecular mechanism in which aS forms different polymorphs under these two conditions. Our results provide novel insights into how the initial conformation impacts fibrillation pathways and kinetics, suggesting that a microenvironment can be used to regulate the intrinsically disordered proteins assembly. [ABSTRACT FROM AUTHOR]