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Fluoride ion (F−) is one of the most hazardous elements in potable water. Over intake of F− can give rise to dental fluorosis, kidney failure, or DNA damage. As a result, developing affordable, equipment-free and credible approaches for F− detection is an important task. In this work, a new three dimensional rare earth cluster-based metal-organic framework assembled from lanthanide Y(III) ion, and a linear multifunctional ligand 3-nitro-4,4′-biphenyldicarboxylic acid, formulated as {[Y(μ3-OH)]4[Y(μ3-OH)(μ2-H2O)0.25(H2O)0.5]4[μ4-nba]8}n (1), where H2nba = 3-nitro-4,4′-biphenyldicarboxylic acid, has been hydrothermally synthesized and characterized through infrared spectroscopy (IR), elemental and thermal analysis (EA), power X-ray diffraction (PXRD), and single-crystal X-ray diffraction (SCXRD) analyses. X-ray diffraction structural analysis revealed that 1 crystallizes in tetragonal system with P 4 ¯ 21m space group, and features a 3D framework with 1D square 18.07(3)2 Å2 channels running along the [0,0,1] or c-axis direction. The structure of 1 is built up of unusual eight-membered rings formed by two types of {Y4O4} clusters connected to each other via 12 μ4-nba2− and 4 μ3-OH− ligands. Three crystallographic independent Y3+ ions display two coordinated configurations with a seven-coordinated distorted monocapped trigonal-prism (YO7) and an eight-coordinated approximately bicapped trigonal-prism (YO8). 1 is further stabilized through O-H⋯O, O-H⋯N, C-H⋯O, and π⋯π interactions. Topologically, MOF 1 can be simplified as a 12-connected 2-nodal Au4Ho topology with a Schläfli symbol {420·628·818}{43}4 or a 6-connected uninodal pcu topology with a Schläfli symbol {412·63}. The fluorescent sensing application of 1 was investigated to cations and anions in H2O. 1 exhibits good luminescence probing turn-on recognition ability toward F− and with a limit detection concentration of F− down to 14.2 μM in aqueous solution (Kec = 11403 M−1, R2 = 0.99289, σ = 0.0539). The findings here provide a feasible detection platform of LnMOFs for highly sensitive discrimination of F− in aqueous media. [ABSTRACT FROM AUTHOR]

A novel series of hybrids designed on the basis of aurantiamide acetate and isopropylated genipin were synthesized and biologically evaluated as anti‐inflammatory agents. Among them, compound 7o exhibited the best inhibitory activity against TNF‐α secretion (IC50 = 16.90 μM) and was selected for further in vitro and in vivo functional study. The results demonstrated that 7o was capable of suppressing the expression of LPS‐induced iNOS and COX‐2, as well as reducing the production of NO at the concentration of 5 μM, which may be resulted from its regulation of NF‐κB signaling and MAPK signaling. Moreover, compound 7o exhibited favorable in vivo anti‐inflammatory activity with an inhibition rate of 53.32% against xylene‐induced ear swelling in mice at the dose of 5 mg/kg. [ABSTRACT FROM AUTHOR]

Twenty‐two novel genipin derivatives have been designed, synthesized, and evaluated for their inhibitory activity against acetylcholinesterase (AChE). As a result, compound 13a bearing ligustrazine moiety displayed the most potent AChE inhibitory activity in this series with IC50 value of 218 nm. Besides, MTT assay was performed to investigate the neuroprotection of these compounds against PC12 cells injured by Amyloid β‐protein 1–42 (Aβ1–42). Among them, 8a showed higher inhibition rate (%Inhibition = 22.29) than the positive reference Donepezil (%Inhibition = 17.65). Novel genipin derivatives were synthesized and biologically evaluated for their inhibitory activity against AChE. 13a displayed the most potent AChE inhibitory activity. Besides, MTT assay was performed to investigate the neuroprotective activity of these compounds in PC12 cells that suffering from injury induced by Aβ1–42. Among them, 8a showed higher inhibition rate than the positive reference Donepezil. [ABSTRACT FROM AUTHOR]

A 1D chain coordination polymer, namely, [Co(L)(4,4′-Bipy)(H2O)]n(1), where Na2L = 2-[(2-Hydroxy-benzylidene)-amino]-benzenesulfonic acid sodium salt and 4,4′-Bipy = 4,4'-bipyridine, has been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. It crystallizes in monoclinic, space groupP2(1)/n. The sulfonate-derived Schiff base serves as a commonN,O,O′-tridentate ligand and 4,4′-Bipy in the complex (1) act asμ2-bridging ligand linking adjacent two metal ions into 1D zigzag infinite chain. The 1D chain is further constructed into 3D networksviaintermolecular hydrogen bonds between the phenolato oxygen atom and coordinated water. [ABSTRACT FROM PUBLISHER]

A new 1D double chains cobalt(II) coordination polymer with the doubly deprotonated Schiff-base and 4,4′-bipyridine ligands, {[Co(Saes)(H2O)(Bipy)]·H2O}n, where H2Saes = 2-(2-hydroxy- benzylideneamino)ethanesulfonic acid, has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy, and elemental and thermogravimetric analysis. The asymmetric unit of 1 comprises two cobalt(II) dimmer with tridentate Schiff-base, 4,4′-bipyridine, and water molecule ligands with the N3O3donor set, exhibiting a slightly distorted octahedral geometry. In the crystal, dimmers are interacted with O-H···O, C-H···O interactions and C-H···πstacking, leading to an interwoven three-dimensional network and stabilizing the coordination complex. The spectral and thermal properties are also discussed. [ABSTRACT FROM AUTHOR]

A new binuclear copper(II) complex with the Schiff-base ligandN-(2-hydroxybenzyl)aminomethanesulfonic acid (H2Saes) has been synthesized, [Cu(Saes) (1,3-dpp)]2(1,3-di(pyridin-4-yl)propane abbreviation as 1,3-dpp) (1), and characterized by single-crystal X-ray diffraction, elemental, IR spectra, and thermogravimetric analyses. Complex 1 shows phenoxo-bridged dinuclear Cu2O2core with intermetallic distance of 3.19 (8) Å. In the crystal structure, 1D infinite chain structure is formed through weakπ-πstacking interactions between the phenyl rings of adjacent dimmer units with ring-centroid distances of 3.787 (4) Å. In addition, 2-D layers structure are formed by intermolecular C-H···O hydrogen bonds with the separate C···O distances of 3.278 (8)-3.533 (9) Å. Molecules from neighboring stacks further interdigitate with each other in the c-direction, leading to an interwoven three-dimensional network held together by C-H···O interactions andπ-stacking and stabilize the coordination complex. [ABSTRACT FROM PUBLISHER]

The title compound, 1, with the formula [Mn2(pmt)2(1,10-phen)2].2ClO4 [N-(2-pyridylmethylidene)taurine (abbreviated as pmt), consists of a structurally centrosymmetric dinuclear MnII complex and two discrete perchlorate anions. Each Mn center is six-coordinated with an N4O2 donors set of the pmt and 1,10-phenanthorline ligands, resulting in a compressed octahedral. In the crystal packing, the component cations interact with pairs of intermolecular C-H···O and π-π contacts forming a 2-D network. Also, the neighboring 2-D cationic layers are connected to each other with C–H···O interactions of perchlorate oxygen atoms with the separate C···O distances of 3.204(7)-3.365(8) Å, giving a supramolecular 3-D network. [Supplemental materials are available for this article. Go to the publisher's online edition of Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry to view the supplemental file.] [ABSTRACT FROM AUTHOR]

A new Schiff base compound, (E)-N'-(5-bromo-2-hydroxy- benzylidene)-4-(quinolin-8-yloxy)butanehydrazide, 1, was synthesized and characterized by elemental analysis, IR spectrum, 1HNMR, and single crystal X-ray diffraction. The asymmetric unit of 1 contains two crystallographic independent molecules with different conformations along the bond sequence linking the benzene and quinoline rings, which have a mean interplanar dihedral angle of 58.9(6) and 10.2(6)°, respectively. In the crystal, the molecules are linked through hydrogen bonds of N-H...O and C-H...O to form an infinite 1-D chain, which is further extended to a supramolecular 3-D network via Br...Br and π...π interactions. The fluorescence property of the compound 1 was investigated. [ABSTRACT FROM AUTHOR]