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A study report about a novel cascade supramolecular complex [Ag(L)](Sb[F.sub.6]).[C.sub.6][H.sub.6] with a reversible nanosized [{[([C.sub.6][H.sub.6]).sub.6][(Sb[F.sub.6].sub.12]}.sup.12-] H-bonded cage unit is presented. It demonstrates a new synthetic strategy to modular host framework that utilizes complicated metal-organic species as the template.

A new one-step combustion method for the facile synthesis of the Ti[O.sub.2] compounds is presented. The application of the self-doped [Ti.sup.3+] compound as a catalyst in the production of hydrogen under visible light is also explained.

A family of discrete chalcogenide T4 clusters ([[[M.sub.x][Ga.sub.18-x][Sn.sub.2][Q.sub.35]].sup.21-], x = 2 or 4, M = Mn, Cu, Zn, Q = S, Se) are described whose discovery has resulted from an unusual phase transformation from a 3-D T4 covalent framework into 0-D T4 molecular clusters. The T4 clusters are the largest molecular supertetrahedral Tn clusters and can be made in various compositions showing tunable band structures in both solution and solid state.

The self-assembly of the largest known Cu-In-S [T.sub.5] supertetrahedral cluster was used to synthesize a Cu-In-S semiconductor consisting of a single piece of a super-supertetrahedron of infinite order. The synthetic realization of the obtained material provides a new method for property engineering of semiconducting materials.

The article presents a new approach, which can be employed for the designing of new [bc.sub.1] complexes, which can be used for the optimization of the interaction with conformationally flexible residues. The complex is shown to be extremely useful as new drugs and agricultural fungicides.

Two highly porous examples of MOCOFs, a new family of framework materials seamlessly integrating the coordinate bonds of metal-oragnic frameworks (MOFs) and covalent bonds of covalent organic framework materials (COFs), are described. These two materials have represented the lightest zeolite RHOs.

Two bent oxadiazole bridging benzoacetylene ligands 2,5-bis(4-ethynylphenyl)-1,3,4-oxadiazole and 2,5-bis(3-ethynylphenyl)-1,3,4-oxadiazole are synthesized. The relative orientation of the pi-donors on the phenyl groups and the five-membered oxadiazole spacing in these ligands resulted in the unusual building blocks, leading to the construction of polymeric motifs.

β-Sialon:Eu2+ has been reported to be the most promising narrow-band green phosphor for wide color gamut LCD backlights, but the coexistence of the Eu3+ luminescence killer with the Eu2+ luminescence center limits its luminescence performance to a great extent. In this study, we propose a direct reduction strategy to successfully realize the reduction of Eu3+ to Eu2+ and, finally, increase the effective concentration of Eu2+ in the crystal lattice and greatly minimize the amount of Eu3+ on the particle surface. As a result, the luminescence of treated β-sialon:Eu2+ is enhanced by 2.3 times, and the internal quantum efficiency significantly increases from 52.2 to 96.5%. The mechanisms for such large enhancements in luminescence are clarified by investigating the microstructure, luminescence spectra, valence state, concentration, and distribution of Eu using a variety of chemical analyses. We find that the low efficiency is ascribed to the coexistence of the Eu3+ luminescence killer with the Eu2+ luminescence center. The white LED backlight using the treated β-sialon:Eu2+ demonstrates a high luminous efficacy of 136 lm W-1 (22.5% up) and a wide color gamut (∼96% National Television System Committee standard (NTSC)), which thus promises high brightness and energy saving. We believe that the strategy proposed in this work would also work for other luminescent materials containing mixed valence of dopants. [ABSTRACT FROM AUTHOR]

A Mn2+-based metal-organic framework (coordination porous framework-5, CPF-5) can serve as a crystalline sponge for single crystal X-ray structural characterization of a variety of compounds using a combination of coordinative alignment and second coordination sphere interactions (e.g., hydrogen bonding). This technique requires only a conventional X-ray source to obtain high quality crystallographic data. [ABSTRACT FROM AUTHOR]

The development of bromodomain and extraterminal domain (BET) bromodomain inhibitors and their examination in clinical studies, particularly in oncology settings, has garnered substantial recent interest. An effort to generate novel BET bromodomain inhibitors with excellent potency and drug metabolism and pharmacokinetics (DMPK) properties was initiated based upon elaboration of a simple pyridone core. Efforts to develop a bidentate interaction with a critical asparagine residue resulted in the incorporation of a pyrrolopyridone core, which improved potency by 9-19-fold. Additional structure-activity relationship (SAR) efforts aimed both at increasing potency and improving pharmacokinetic properties led to the discovery of the clinical candidate 63 (ABBV-075/mivebresib), which demonstrates excellent potency in biochemical and cellular assays, advantageous exposures and half-life both in animal models and in humans, and in vivo efficacy in mouse models of cancer progression and inflammation. [ABSTRACT FROM AUTHOR]

The prediction of fluid phase behavior in nanoscale pores is critical for shale gas/oil development. In this work, we use a molecular density functional theory (DFT) to study the effect of molecular size and shape on partitioning to graphite nanopores as a model of shale. Here, interfacial statistical associating fluid theory (iSAFT) is applied to model alkane (C1 - C8) adsorption/desorption/phase behavior in graphite slit pores for both pure fluids and mixtures. The pure component parameters were fit to the bulk saturated liquid density and vapor pressure data in selected temperature ranges. The potential of interaction between the fluid and graphite is modeled with a Steele 10-4-3 potential that is fit to the potential of mean force from single-molecule simulations. Good agreement is found between theory and molecular simulation for the density distributions of pure components in slit pores. The critical properties of methane, ethane, and their mixtures as well as the shift in bubble point and dew point densities were studied, showing good agreement with simulation. The competitive adsorption of mixtures of normal and branched alkanes in graphite pores was also studied. Heavier components more strongly adsorb up to the point that the entropic penalty due to confinement reduces adsorption. [ABSTRACT FROM AUTHOR]

Catalytic direct conjugate addition and [2 + 2] cycloaddition reactions of β,γ-unsaturated α-ketoesters with simple olefins have been developed, affording vinylation products and functionalized cyclobutanes, respectively, in good yields with high regioselectivity. [ABSTRACT FROM AUTHOR]

Members of the BET family of bromodomain containing proteins have been identified as potential targets for blocking proliferation in a variety of cancer cell lines. A two-dimensional NMR fragment screen for binders to the bromodomains of BRD4 identified a phenylpyridazinone fragment with a weak binding affinity (1, K i = 160 μM). SAR investigation of fragment 1, aided by X-ray structure-based design, enabled the synthesis of potent pyridone and macrocyclic pyridone inhibitors exhibiting single digit nanomolar potency in both biochemical and cell based assays. Advanced analogs in these series exhibited high oral exposures in rodent PK studies and demonstrated significant tumor growth inhibition efficacy in mouse flank xenograft models. [ABSTRACT FROM AUTHOR]

The development of facile and versatile strategies with low-cost for hydrogel construction is of tremendous scientific interest. Herein, we demonstrate that naturally derived, cost-effective tannic acid (TA) can be an efficient gelation binder for the hydrogel formation with a series of commercially available water-soluble polymers. With a five-polyphenol-arm structure, TA molecules are able to grasp polymer chains through either hydrogen or ionic bonds and cross-link them together by coordinate bonds in the presence of Fe(III) ions. These two interactions can be elegantly balanced by tuning the weight ratios of polymer/TA and TA/Fe3+, which is the key point for the construction of supramolecular hydrogels. The supramolecular hydrogels exhibit multiple functionalities including mechanical tenability, rapid self-healing, pH-stimuli responsiveness, and free radical scavenging abilities. TA as a dynamic and versatile catechol group modifier provides a simple path to the construction of multifunctional hydrogels, which shows obvious advantages such as easy and green processing, low cost, and large-scale preparation. [ABSTRACT FROM AUTHOR]

A new strategy was developed by using a polymer ligand, poly(isophthalic acid)(ethylene oxide), to modulate the growth of metal–organic polyhedra (MOP) crystals. This macromolecular modulator can effectively control the crystal habit of several different Cu24L24 (L = isophthalic acid derivatives) MOPs. The polymer also directed the formation of MOP structures under reaction conditions that only produce metal–organic frameworks in the absence of modulator. Moreover, the polymer also enabled the deposition of MOP crystals on glass surfaces. This macromolecular modulator strategy provides an innovative approach to control the morphology and assembly of MOP particles. [ABSTRACT FROM AUTHOR]

Luminescent materials play an important role in making solid state white light-emitting diodes (w-LEDs) more affordable home lighting applications. To realize the next generation of solid-state w-LEDs with high color-rendering index (CRI), the discovery of broad band and long emission wavelength luminescent materials is an urgent mission. Regarding this, the oxonitridosilicate Y3Si5N9O with a high nitrogen concentration should be a suitable host material to achieve those promising luminescent properties. In this work, a phase-pure Ce3+-doped Y3Si5N9O was successfully synthesized through the carbothermal reduction and nitridation method. Y3Si5N9O:Ce3+ shows an emission maximum at 620 nm and an extremely broad emission band with a full-width at half-maximum (fwhm) of 178 nm. The electronic and crystal structure calculations indicate an indirect band gap of 2.6 eV (experimental value: 4.0 eV), and identify two Ce3+ sites with different local environments that determine the luminescence properties. The orange-emitting phosphor has the absorption, internal and external quantum efficiencies of 89.5, 17.2, and 15.6% under 450 nm excitation, respectively. The valence state of Ce, cathodoluminescence, decay time, and thermal quenching of the phosphor were also investigated to understand the structure-property relationships. [ABSTRACT FROM AUTHOR]

The thermodynamics of hydrogen bonding in 1-alcohol + water binary mixtures is studied using molecular dynamic (MD) simulation and the polar and perturbed chain form of the statistical associating fluid theory (polar PC-SAFT). The fraction of free monomers in pure saturated liquid water is computed using both TIP4P/2005 and iAMOEBA simulation water models. Results are compared to spectroscopic data available in the literature as well as to polar PC-SAFT. Polar PC-SAFT models hydrogen bonds using single bondable association sites representing electron donors and electron acceptors. The distribution of hydrogen bonds in pure alcohols is computed using the OPLS-AA force field. Results are compared to Monte Carlo (MC) simulations available in the literature as well as to polar PC-SAFT. The analysis shows that hydrogen bonding in pure alcohols is best predicted using a two-site model within the SAFT framework. On the other hand, molecular simulations show that increasing the concentration of water in the mixture increases the average number of hydrogen bonds formed by an alcohol molecule. As a result, a transition in association scheme occurs at high water concentrations where hydrogen bonding is better captured within the SAFT framework using a three-site alcohol model. The knowledge gained in understanding hydrogen bonding is applied to model vapor-liquid equilibrium (VLE) and liquid-liquid equilibrium (LLE) of mixtures using polar PC-SAFT. Predictions are in good agreement with experimental data, establishing the predictive power of the equation of state. [ABSTRACT FROM AUTHOR]

As an extension of nitride luminescent materials, carbidonitride phosphors are also attracting great attention due to their superior thermal stability. This paper reports a blue-emitting carbidonitride phosphor Al1-xSixCxN1-x:Eu2+ suitable for near ultraviolet (UV) light emitting diodes (LEDs), which is formulated by introducing SiC into AlN:Eu2+. With the introduction of carbon (silicon), the lattice abnormally shrinks along both a- and c-axes at low x values (x = 0.08), due to the formation of a dense interlayer for accommodating the luminescence center Eu2+. Both of the Raman spectra and solid state NMR spectroscopy show that both Si and C are dissolved in the AlN lattice. A single blue emission band (λem = 472-477 nm) is observed for compositions of x > 0.05 by cathodoluminescence measurements. Under the 365 nm excitation, the maximum luminescence is attained for the composition of x = 0.06 that has an external quantum efficiency of 61% and absorption efficiency of 74.4%, which is about 11-15% higher than the corresponding carbon-free nitride sample. The thermal quenching of Al1-xSixCxN1-x:Eu2+ reduces with increasing C (SiC) content, and the sample of x = 0.06 shows a small loss of ~4.0% in quantum efficiency even at 200 °C. Using this phosphor in a near UV-driven white LED, a superhigh color rendering index of Ra = 95.3 and R9 = 72 as well as a color temperature of 3533 K are achieved. [ABSTRACT FROM AUTHOR]

Theperturbed chain form of the polar statistical associating fluidtheory (Polar PC-SAFT) was used to model lower 1-alcohol + n-alkane mixtures. The ability of the equation of stateto predict accurate activity coefficients at infinite dilution wasdemonstrated as a function of temperature. Investigations show thatthe association term in SAFT plays an important role in capturingthe right composition dependence of the activity coefficients in comparisonwith nonassociating models (UNIQUAC). Results also show that consideringlong-range polar interactions can significantly improve the fractionsof free monomers predicted by PC-SAFT in comparison with spectroscopicdata and molecular dynamic (MD) simulations carried out in this work.Furthermore, evidence of hydrogen-bonding cooperativity in 1-alcohol+ n-alkane systems is discussed using spectroscopy,simulation, and theory. In general, results demonstrate the theory’spredictive power, limitations of first-order perturbation theories,as well as the importance of considering long-range polar interactionsfor better hydrogen-bonding thermodynamics. [ABSTRACT FROM AUTHOR]

A series of Eu2+- and Mn2+-codoped γ-AlON (Al1.7O2.1N0.3) phosphors was synthesized at 1800 °C under 0.5 MPa N2 by using the gas-pressure sintering method (GPS). Eu2+ and Mn2+ ions were proved to enter into γ-AlON host lattice by means of XRD, CL, and EDS measurements. Under 365 nm excitation, two emission peaks located at 472 and 517 nm, resulting from 4f65d¹ → 4f7 and 4T1(4G) → 6A1 electron transitions of Eu2+ and Mn2+, respectively, can be observed. Energy transfer from Eu2+ to Mn2+ was evidenced by directly observing appreciable overlap between the excitation spectrum of Mn2+ and the emission spectrum of Eu2+ as well as by the decreased decay time of Eu2+ with increasing Mn2+ concentration. The critical energy-transfer distance between Eu2+ and Mn2+ and the energy-transfer efficiency were also calculated. The mechanism of energy transfer was identified as a resonant type via a dipole-dipole mechanism. The external quantum efficiency was increased 7 times (from 7% for γ-AlON:Mn2+ to 49% for γ-AlON:Mn2+,Eu2+ under 365 nm excitation), and color-tunable emissions from blue-green to green-yellow were also realized with the Eu2+ → Mn2+ energy transfer in γ-AlON. [ABSTRACT FROM AUTHOR]

Myeloid cell leukemia 1 (MCL-1) is a BCL-2 family protein that has been implicated in the progression and survival of multiple tumor types. Herein we report a series of MCL-1 inhibitors that emanated from a high throughput screening (HTS) hit and progressed via iterative cycles of structure-guided design. Advanced compounds from this series exhibited subnanomolar affinity for MCL-1 and excellent selectivity over other BCL-2 family proteins as well as multiple kinases and GPCRs. In a MCL-1 dependent human tumor cell line, administration of compound 30b rapidly induced caspase activation with associated loss in cell viability. The small molecules described herein thus comprise effective tools for studying MCL-1 biology. [ABSTRACT FROM AUTHOR]