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A new family of binuclear lanthanidecompounds of general formula [Ln(2,4-DClBA)3phen]2(Ln(III) = Nd (1), Sm (2), Dy (3), Yb (4); 2,4-DClBA = 2,4-dichlorobenzoate; phen =1,10-phenanthroline) have been synthesized and characterized by elementalanalysis, molar conductance, infrared spectroscopy, ultraviolet spectra,thermogravimetric analysis, and single-crystal X-ray diffraction.On the basis of X-ray crystallography, compounds 2–4belong to the triclinic crystal system, PI̅ space group. In compound 2, the Sm3+ion adopted a distorted monocapped square-antiprism coordinationgeometry. Compounds 3and 4are isomorphouswhose central ions (Dy3+and Yb3+) formed adistorted square-antiprism geometry. The heat capacities of compounds 1–4are measured using DSC technologyand fitted to a polynomial equation by the least-squares method. Thesmoothed molar heat capacities and thermodynamic function data ofcompounds 1–4relative to the referencetemperature 298.15 K are then calculated. Meanwhile, these compoundsexhibit in good antifungal activity against C. albicans, good antibacterial activity against S. aureus, and better antibacterial activity against E. coli. The fluorescence spectra of the samarium and dysprosium compoundsbehave as characteristic transitions of Sm(III) and Dy(III) ions. [ABSTRACT FROM AUTHOR]

Two novel complexes ([Ln(3,5-Dipr-2-OHBA)3(phen)]2(Ln = Dy(1), Yb(2); 3,5-Dipr-2-OHBA = 3,5-diisopropylsalicylicacid; phen = 1,10-phenanthroline)) were synthesized and characterizedby elemental analysis, conductivity measurements, IR spectra, singlecrystal X-ray diffraction, and thermogravimetric differential scanningcalorimetry/Fourier transform infrared (TG/DSC-FTIR) technology. Thefluorescent property of complex 1 was also studied. The two binuclearcomplexes are isostructural. Each Ln3誉 is octa-coordinated,yielding a trigondodecahedron conformation. The thermal propertiesof the title complexes were investigated by simultaneous TG/DSC-FTIRtechniques. The kinetic parameters of the first decomposition stagefor the complexes were calculated by the integral isoconversionalnonlinear method (NL-INT method), Starink method, Kissinger’smethod, and Ozawa–Doyle’s method. The thermodynamicparameters (ΔH≠, ΔG≠, and ΔS≠) at the peak temperatures of the DTG curves were alsocalculated. Heat capacities of the two complexes were measured byDSC. The values of the experimental heat capacities were fitted toa polynomial equation with the least-squares method. Besides, thesmoothed heat capacities and thermodynamic functions (HT– H298.15K),(ST– S298.15K), and (GT– G298.15K) were calculated. [ABSTRACT FROM AUTHOR]

The complex [Ho(2,4-DClBA)3bipy]2(2,4-DClBA = 2,4-dichlorobenzoate; bipy = 2,2′-bipyridine) was synthesized and characterized by elemental analysis, infrared spectra, ultraviolet spectra, single-crystal X-ray diffraction, thermogravimetry, and differential thermogravimetry (TG-DTG) techniques. The crystal is monoclinic with space group P2(1)/n. The coordination number of the Ho3誉 is nine. Two Ho3誉 are connected via two bidentate bridging and two bidentate chelating−bridging modes. The thermal decomposition behavior of the title complex under a nitrogenous atmosphere was studied using the TG-DTG and IR techniques. The nonisothermal kinetics was investigated by using the Popescu method and the integral isoconversional nonlinear method (NL-INT). The mechanism function of the first decomposition step was determined. The thermodynamic parameters (ΔG⧧, ΔH⧧, and ΔS⧧) were also calculated, and kinetic parameters (activation energy Eand the pre-exponential factor A) were also obtained. [ABSTRACT FROM AUTHOR]

To address electromagnetic interference (EMI) pollution in modern society, the development of ultrathin, high-performance, and highly stable EMI shielding materials is highly desired. Liquid metal (LM) based conductive materials have received enormous amounts of attention. However, the processing approach of LM/polymer composites represents great challenges due to the high surface tension and cohesive energy of LMs. In this study, we develop a universal one-step fabrication strategy to directly process composites containing LMs and cellulose nanofibrils (CNFs) and successfully fabricate the ultrathin, flexible, and stable EMI shielding films with an average specific EMI shielding efficiency (EMI SE) value of 429 dB/mm and small thickness of only 70 μm in the wide frequency range of 8.2-18 GHz. In addition, the resulting films also exhibit excellent mechanical performance and flexibility, which endow the film with the ability to withstand repeated folding, bending, and folding into complex shapes without producing cracks or fractures. Besides, the resulting films display excellent thermal conductivity with a λ of 4.90 W/(m K) and an α of 3.17 mm 2 /s. Thus, the presented approach shows great potential in fabricating advanced materials for EMI shielding applications.

During the past 20 years, many studies have focused on polyphenol compounds for their potential beneficial health effects. Flavonoids represent a large class of phenolic compounds found in fruits, vegetables, nuts, grains, cocoa, tea, and other beverages. Flavonoids have shown antioxidant and anti-inflammatory activities. Given the putative relationship between inflammation and insulin resistance, the consumption of flavonoids or flavonoid-rich foods has been suggested to reduce the risk of diabetes by targeting inflammatory signals. This is the first comprehensive review summarizing the current research progress on the inhibition of inflammation and alleviation of insulin resistance by flavonoids as well as the mechanistic link between these disorders. Laboratory and human studies on the activities of major flavonoids (flavones, isoflavones, flavonols, etc.) are discussed.

We recently reported a new molecular heterocyclic friction modifier (FM) that exhibits excellent friction and wear reduction in the boundary lubrication regime. This paper explores the mechanisms by which friction reduction occurs with heterocyclic alkyl-cyclen FM molecules. We find that these chelating molecules adsorb onto (oxidized) steel surfaces far more tenaciously than conventional FMs such as simple alkylamines. Molecular dynamics simulations argue that the surface coverage of our heterocyclic FM molecules remains close to 100% even at 200 °C. This thermal stability allows the FMs to firmly anchor to the surface, allowing the hydrocarbon chains of the molecules to interact and trap base oil lubricant molecules. This results in thicker boundary film thickness compared with conventional FMs, as shown by optical interferometry measurements.

The advent of DNA technology has demonstrated great potential in a wide range of applications, especially in the field of biology and biomedicine. However, current understanding of the toxicological effects and cellular responses of DNA nanostructures remains to be improved. Here, we chose tetrahedral DNA nanostructures (TDNs), a type of nanocarriers for delivering molecular drugs, as a model for systematic live-cell analysis of the biocompatibility of TDNs to normal bronchial epithelial cells, carcinoma cells, and macrophage. We found that the interaction behaviors of TDNs in different cell lines were very different, whereas after internalization, most of the TDNs in diverse cell lines were positioned to lysosomes. By a systematic assessment of cell responses after TDN exposure to various cells, we demonstrate that internalized TDNs have good innate biocompatibility. Interestingly, we found that TDN-bearing cells would not affect the cell cycle progression and accompany cell division and that TDNs were separated equally into two daughter cells. This study improves our understanding of the interaction of DNA nanostructures with living systems and their biocompatibility, which will be helpful for further designing DNA nanostructures for biomedical applications.

Poly( N-isopropylacrylamide) (PNIPAM)-based ionic microgels with different diameters were first prepared and then used as particulate stabilizer or seed in dispersion polymerization of styrene. The role of PNIPAM-based ionic microgels could be transformed from particulate stabilizer to seed by controlling the water content in methanol-water mixture. Generally, PNIPAM-based ionic microgels served as particulate stabilizer in methanol in the absence of water, leading to the formation of spherical polystyrene nanoparticles. However, they turned into seeds when water was added into the methanol solution, with the formation of octopus-like nanoparticles. Further study demonstrated that the mechanism for this role transition was related to the special thermosensitivity of PNIPAM microgels in methanol-water mixture. They lost their thermosensitivity in pure methanol solution but restored their thermosensitivity when increasing the water content in methanol-water mixture.

Herein we report the discovery and hit-to-lead optimization of a series of spirocyclic piperidine aldosterone synthase (CYP11B2) inhibitors. Compounds from this series display potent CYP11B2 inhibition, good selectivity versus related CYP enzymes, and lead-like physical and pharmacokinetic properties.

Hit-to-lead efforts resulted in the discovery of compound 19, a potent CYP11B2 inhibitor that displays high selectivity vs related CYPs, good pharmacokinetic properties in rat and rhesus, and lead-like physical properties. In a rhesus pharmacodynamic model, compound 19 displays robust, dose-dependent aldosterone lowering efficacy, with no apparent effect on cortisol levels.

We report the discovery of a benzimidazole series of CYP11B2 inhibitors. Hit-to-lead and lead optimization studies identified compounds such as 32, which displays potent CYP11B2 inhibition, high selectivity versus related CYP targets, and good pharmacokinetic properties in rat and rhesus. In a rhesus pharmacodynamic model, 32 produces dose-dependent aldosterone lowering efficacy, with no apparent effect on cortisol levels.

Biaryl cyclohexene carboxylic acids were discovered as full and potent niacin receptor (GPR109A) agonists. Compound 1e (MK-6892) displayed excellent receptor activity, good PK across species, remarkably clean off-target profiles, good ancillary pharmacology, and superior therapeutic window over niacin regarding the FFA reduction versus vasodilation in rats and dogs.

Tricyclic analogues were rationally designed as the high affinity niacin receptor G-protein-coupled receptor 109A (GPR109A) agonists by overlapping three lead structures. Various tricyclic anthranilide and cycloalkene carboxylic acid full agonists were discovered with excellent in vitro activity. Compound 2g displayed a good therapeutic index regarding free fatty acids (FFA) reduction and vasodilation effects in rats, with very weak cytochrome P450 2C8 (CYP2C8) and cytochrome P450 2C9 (CYP2C9) inhibition, and a good mouse pharmacokinetics (PK) profile.

Biaryl anthranilides are reported as potent and selective full agonists for the high affinity niacin receptor GPR109A. The SAR presented outlines approaches to reduce serum shift and both CYPCYP2C8 and CYP2C9 liabilities, while improving PK and maintaining excellent receptor activity. Compound 2i exhibited good in vivo antilipolytic efficacy while providing a significantly improved therapeutic index over vasodilation (flushing) with respect to niacin in the mouse model.