Ethanol Extract of Citrus grandis 'Tomentosa' Exerts Anticancer Effects by Targeting Skp2/p27 Pathway in Non-Small Cell Lung Cancer.

SCOPE: This study aims to investigate the anticancer properties of Citrus grandis 'Tomentosa' (CGT) in non-small cell lung cancer (NSCLC). METHODS AND RESULTS: The ethanol extract of CGT (CGTE) is prepared by using anhydrous ethanol and analyzed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), revealing that the main chemical components in CGTE are flavonoids and coumarins, such as naringin, rhoifolin, apigenin, bergaptol, and osthole. CGTE at concentrations without inducing cell death significantly inhibits cell proliferation via inducing cell cycle G1 phase arrest by MTT, colony formation, and flow cytometry assays, implying that CGT has anticancer potential. CGTE markedly inhibits the activity of Skp2-SCF E3 ubiquitin ligase, decreases the protein level of Skp2, and promotes the accumulation of p27 by co-immunoprecipitation (co-IP) and in vivo ubiquitination assay; whereas Skp2 overexpression rescues the effects of CGTE in NSCLC cells. In subcutaneous LLC allograft and A549 xenograft mouse models, CGTE, without causing obvious side effects in mice, significantly inhibits lung tumor growth by targeting the Skp2/p27 signaling pathway. CONCLUSION: These findings demonstrate that CGTE efficiently inhibits NSCLC proliferation both in vitro and in vivo by targeting the Skp2/p27 signaling pathway, suggesting that CGTE may serve as a therapeutic candidate for NSCLC treatment.

Organocatalytic ß,γ-Selective Activation of Deconjugated Butenolides Access to Chiral Tricyclic Chroman-butyrolactones.

A highly efficient method for the ß,γ-selective activation of deconjugated butenolides has been developed through an organocatalytic asymmetric vinylogous cascade reaction. This protocol enables the construction of a broad range of substituted tricyclic chroman-butyrolactones by vinylogous Michael/oxa-Michael pathways in good yield (up to 89%) with good to high enantioselectivity (up to 97:3 er) and excellent diastereoselectivity. The ring-opening esterification of butyrolactones was also demonstrated.

Self-Template Synthesis of Co-Se-S-O Hierarchical Nanotubes as Efficient Electrocatalysts for Oxygen Evolution under Alkaline and Neutral Conditions.

We develop a facile self-template synthetic method to construct hierarchical Co-Se-S-O (CoSe xS2- x@Co(OH)2) nanotubes on a carbon cloth as a self-standing electrode for electrocatalytic oxygen evolution reaction (OER). In the synthetic process, separate selenization and sulfurization on the Co(OH)F precursor in different solvents have played an important role in constructing CoSe xS2- x (Co-Se-S) hierarchical nanotubes, which was further transformed into the nanotube-like Co-Se-S-O via an in situ electrochemical oxidation process. The Co-Se-S-O obtained by the Kirkendall effect through two stepwise anion-exchange reactions represents the first quaternary Co-Se-S-O nanotube array, which dramatically enhances its surface area and conductivity. Further, it only requires low overpotentials of 230 and 480 mV to achieve a 10 mA cm-2 current density. The OER performance of Co-Se-S-O is much more efficient than that of its monochalcogenide counterparts, as well as the commercial benchmark catalyst IrO2.

Rationally Designed 2D Covalent Organic Framework with a Brick-Wall Topology.

We report the design and synthesis of an imine-based two-dimensional covalent organic framework (2D COF) with a novel brick-wall topology by judiciously choosing a tritopic T-shaped building block and a ditopic linear linker. Unlike the main body of COF frameworks reported to-date, which consists of higher-symmetry 2D topologies, the unconventional layered brick-wall topology have only been proposed but never been realized experimentally. The brick-wall structure was characterized by powder X-ray diffraction analysis, FT-IR, solid state 13C NMR spectroscopy, nitrogen, and carbon oxide adsorption-desorption measurements as well as theoretical simulations. Our present work opens the door to the design of novel 2D COFs and will broaden the scope of emerging COF materials.

Tubular metal-organic framework-based capillary gas chromatography column for separation of alkanes and aromatic positional isomers.

In this work, a tubular metal-organic framework, MOF-CJ3, with a large one-dimensional channel was chosen as stationary phase to prepare a capillary gas chromatographic column via a verified dynamic coating procedure. The column offered good separations of linear and branched alkanes, as well as aromatic positional isomers (ethylbenzene, xylene, cresol, hydroquinone, dichlorobenzene, bromobenzonitrile, chloronitrobenzene, and nitrotoluene) based on a combination of host-guest interactions and adsorption effects. Elution sequence of most of the analytes followed an increasing order of their boiling points, except for the separation of n-heptanes/isooctane, cresol, and hydroquinone isomers. Separation behavior of the column upon different organic substances may be related to the tubular pore structure of MOF-CJ3, in which the van der Waals forces between the alkanes and the hydrophobic inner surfaces might have great effect on separation of n-heptanes and isooctane, whereas the separation of cresol and hydroquinone isomers were affected by (OH⋯O) hydrogen bonds formed between the analytes and the 1,3,5-benzenetricarboxylate ligands on the pore wall. The effects of temperature on separation of aromatic positional isomers were investigated to elucidate entropy and enthalpy controlling of the separation process.

Bis(µ-2-hydroxy-benozato)-κO,O':O';κO:O,O'-bis-[(2-hydroxy-benozato-κO,O')(1,10-phenanthroline-κN,N')cadmium(II)].

The dinuclear title compound, [Cd(2)(C(7)H(5)O(3))(4)(C(12)H(8)N(2))(2)], is located on a crystallographic rotation twofold axis. The two Cd(II) ions are connected by two tridentate bridging 2-hydroxy-benzoate anions. Each Cd(II) ion is seven-coordinated by five O atoms from three 2-hydroxy-benzoate ligands and two N atoms from 1,10-phenanthroline. The 2-hydroxy-benzoate mol-ecules adopt two kinds of coordination mode, bidentate chelating and tridentate bridging-chelating. Intra-molecular hydrogen bonds between hydr-oxy and carboxyl-ate groups from 2-hydroxy-benzoate groups and π-π stacking interactions between parallel 1,10-phenanthroline ligands [centroid-centroid distances = 3.707 (3) and 3.842 (3) Å] are observed. Furthermore, adjacent benzene rings from 2-hydroxy-benzoate ligands are involved in π-π inter-actions with inter-planar distances of 3.642 (3) Å, thereby forming a chain along the a axis direction.