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The design and preparation of chiral metal-organic frameworks (CMOFs) from achiral ligands are a big challenge. Using 3-nitro-4-(pyridin-4-yl)benzoic acid (HL) as a new linker, a total of eight chiral lanthanide-organic frameworks (LOFs), namely poly[diaquatris[μ2-3-nitro-4-(pyridin-4-yl)benzoato-κ2 O:O′]-lanthanide(III)], l- and d-[Ln(C12H7N2O4)3(H2O)2]n [(1), Ln = Eu; (2), Ln = Gd; (3), Ln = Dy, (4), Ln = Tb], were hydrothermally synthesized without chiral reagents and determined by X-ray crystallography. Crystal structure analyses show that l-(1)-(4) crystallize in the hexagonal P65 space group and are isomorphous and isostructural, while the enantiomers d-(1)-(4) crystallize in the hexagonal P61 space group. All LnIII ions are octacoordinated by six carboxyl O atoms of six 3-nitro-4-(pyridin-4-yl)benzoate ligands and two water molecules in a dodecahedral geometry. A one-dimensional neutral helical [Ln2(CO2)3]n chain is observed in (1)-(4) as a chiral origin. These helical chains are further interconnected via directional hydrogen-bonding interactions between pyridyl groups and water molecules to construct a three-dimensional (3D) homochiral network with hex topology. The present CMOF structure is the first chiral 3D hydrogen-bonded hex-net and shows good water stability. Solid-state circular dichroism (CD) signals revealed that (1)-(4) crystallized through spontaneous resolution. Furthermore, (1) and (4) display a strong red and green photoluminescence at room temperature, respectively, but their intensities reduce to almost half at 200 °C. Notably, upon excitation under visible light (463 nm), a circularly polarized luminescence (CPL) of (1) in the solid state is observed for the first time, with a glum value of 2.61 κ 10×-2. [ABSTRACT FROM AUTHOR]

A series of novel 4-arylaminoquinazoline derivatives were synthesized by five-step reactions, the structure was characterized by IR, 1H NMR, MS and single crystal X-ray diffraction. The result of 5aX crystal was as follows: the crystal belongs to the monoclinic system, space group P21/c with a = 12.3637(4) Å, b = 12.7902(2) Å, c = 13.2240(5) Å, α = 90°, β = 117.030(5)°, γ = 90°, V = 1862.75(12) Å3, Z = 2, F(000) = 804.0, µ = 0.095 mm-1, S = 1.039, R = 0.0569, wR = 0.1535 for 8417 observed reflections with I > 2σ(I). The compound 5cX exhibited an excellent inhibitory effect on the cell line A549 (IC50 < 2.5 µM) and the drug-resistant cell line H1975 (IC50 < 2.5 µM) by the biological activity, which were superior to the positive control Zorifertinib (against A549: IC50 = 31.08 µM; against H1975: IC50 = 64.17 µM). Molecular docking revealed that the better inhibitory activity of compound 5cX was owing to the combining EGFRWT and EGFRL858R/T790M by hydrogen bonding. The physicochemical properties of the compounds were predicted by using ADME data analysis, and the results showed that the compounds all obeyed Lipinski's five rules. [ABSTRACT FROM AUTHOR]

One novel cyanide-bridged mixed-valence {FeIII 2 (μ -CN) 4 FeII 2 } square cluster exhibits thermally-induced, reversible, complete spin transition behaviour at two out of four metal centers. • One novel cyano-bridged mixed-valence bimetallic {FeIII 2 (μ -CN) 4 FeII 2 } cluster has been prepared. • The square cluster exhibits thermally-induced, reversible, complete spin transition behavior. One novel cyano-bridged mixed-valence bimetallic {FeIII 2 (μ -CN) 4 FeII 2 } cluster, {[(Tp)FeIII(CN) 3 ] 2 [FeII(Py 2 N 2)] 2 }·(PF 6) 2 (1), has been synthesized (Tp = hydrotris(pyrazolyl)borate, Py 2 N 2 = N,N'-bis(2-pyridylmethyl)-N,N'-bis(4-benzyl)-1,2-ethanediamine). The molecular structure has been determined by single-crystal X-ray diffraction. Compound 1 exhibit temperature driven Fe(II) spin crossover behaviour (SCO) associated with the high-spin (HS) ↔ low-spin (LS) transition with the transition temperature of 130 K at two out of four metal centers. The evolution of HS and LS Fe(II) ions with temperature was followed by FT-IR, X-ray crystallography, the variable temperature magnetic susceptibility. [ABSTRACT FROM AUTHOR]