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Isoliquiritigenin (ILTG) possesses many pharmacological properties. However, its poor solubility and stability in water hinders its wide applications. The solubility of bioactive compounds can often be enhanced through preparation and delivery of various cyclodextrin (CD) inclusion complexes. The 6-O-α-D-maltosyl-β-CD (G2-β-CD), as one of the newest developments of CDs, has high aqueous solubility and low toxicity, especially stable inclusion characteristics with bioactive compounds. In this work, we for the first time construct and characterize the supermolecular structure of ILTG/G2-β-CD by scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffractometry (XRD). The solubility of ILTG in water at 25 °C rises from 0.003 to 0.717 mg/mL by the encapsulation with G2-β-CD. Our experimental observations on the presence of the ILTG/G2-β-CD inclusion complex are further supported by the ONIOM(our Own N-layer Integrated Orbital molecular Mechanics)-based QM/MM (Quantum Mechanics/Molecular Mechanics) calculations, typically substantiating these supermolecular characteristics, such as detailed structural assignments, preferred binding orientations, selectivity, solvent effects, interaction energies and forces of the ILTG/G2-β-CD inclusion complex. Our results have elucidated how ILTG interacts with G2-β-CD, demonstrating the primary host-guest interactions between ILTG and G2-β-CD, characterized by hydrogen bonds, hydrophobic interactions, electrostatic forces, and conformational effects, are favored for the formation of the ILTG/G2-β-CD inclusion. [ABSTRACT FROM AUTHOR]

Herein, we develop a reproducible in situ crystallization route to synthesize uniform functional ZSM-5 microspheres composed of aggregated ZSM-5 nanorods and well-dispersed uniform Fe3O4 nanoparticles (NPs). The growth of such unique microspheres undergoes a NP-assisted recrystallization process from surface to core. The obtained magnetic ZSM-5 microspheres possess a uniform size (6-9 μm), ultrafine uniform Fe3O4 NPs (10 nm), good structural stability, high surface area (340 m2/g), and large magnetization (~8.6 emu/g) and exhibit a potential application in Fischer-Tropsch synthesis. [ABSTRACT FROM AUTHOR]

Reactions of a series of unsymmetrically substituted N-heterocyclic carbene ligands with Ru3(CO)12afforded a variety of mononuclear (1, 2), trinuclear (3, 4, 5, and 5′), and tetranuclear (6, 7) ruthenium complexes via intramolecular ruthenium-mediated sp2and sp3C–H bond activations. Complexes 6and 7include an octahedral cluster skeleton consisting of four ruthenium atoms and two metalated carbon atoms. The formation of this type of ruthenium clusters is proposed to involve the initial C–C double-bond migration and subsequent sp2C–H bond activations. All new complexes were fully characterized, and the molecular structures of 1, 2, 5, 6, and 7were determined by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Thermal treatment of Ru3(CO)12with equimolar amounts of (1H-inden-3-yl)diphenylphosphine and (1H-inden-2-yl)diphenylphosphine in octane gave two isomeric trinuclear ruthenium clusters Ru3(μ2-H)(μ3-3-Ph2PC9H6)(CO)9(1) and Ru3(μ2-H)(μ3-2-Ph2PC9H6)(CO)9(2), respectively, via a C−H bond cleavage. Heating either 1or 2in octane afforded the trinuclear and tetranuclear ruthenium clusters Ru3(μ3-PPh)(μ3-C9H6)(CO)9(3) and Ru4(μ4-PPh)(μ4-C9H6)(CO)11(4) via double C−P bond cleavage. Thermal treatment of Ru3(CO)12with (4,7-dimethyl-1H-inden-3-yl)diphenylphosphine in octane gave trinuclear ruthenium cluster Ru3(μ2-H)(μ3-3-Ph2PC11H10)(CO)9(5) via a C−H bond cleavage. Heating 5in octane afforded a trinuclear ruthenium cluster Ru3(μ3-PPh)(μ3-C11H10)(CO)9(6) and two isomeric tetranuclear ruthenium clusters Ru4(μ3-PPh)(μ2-η5:η1-C11H10)(CO)11(7) and [Ru4(μ4-PPh)(μ4-C11H10)(CO)11] (8) via double C−P bond cleavage. Thermal treatment of Ru3(CO)12with (3,4,7-trimethyl-1H-inden-1-yl)diphenylphosphine in toluene afforded two trinuclear ruthenium clusters Ru3(μ2-H)2(μ3-3-Ph2PC12H11)(CO)8(9) via both sp3and sp2C−H bond cleavage and Ru3(μ2-PPh2)(μ3-η2:η2:η5-C12H13)(CO)6(10) via a C−P bond cleavage. Thermal treatment of Ru3(CO)12with (3-methyl-1H-inden-1-yl)diphenylphosphine in toluene afforded a trinuclear ruthenium cluster Ru3(μ2-H)(μ3-3-Ph2PC10H8)(CO)9] (11) via a C−H bond cleavage. The molecular structures of complexes 1−5and 7−11have been determined by single-crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Thermal treatment of dihydrooctamethyl-s-indacene with Ru3(CO)12afforded the trinuclear and tetranuclear complexes Ru3(η5:η5:η2-C20H24)(CO)7(1) and Ru4(η5:η4:η1-C20H24)(μ-CO)2(CO)7(2), via intramolecular sp3C−H bond activation, and the mononuclear complex Ru(η5-C20H25)(CO)2Cl (3), which might be formed via chlorination of a terminal hydride complex during column chromatography. Reaction of 1,2,3,4,7-pentamethylindene with Ru3(CO)12also yielded the tetranuclear complex Ru4(η5:η3:η2-C14H16)(CO)9(4) via the same sp3C−H bond activation, together with the dinuclear complex [(η5-C9H2Me5)Ru(CO)]2(μ-CO)2(5). In contrast, reaction of 4,7-dimethylindene with Ru3(CO)12gave only the dinuclear complex [(η5-C9H5Me2)Ru(CO)]2(μ-CO)2(6). The molecular structures of all six complexes have been determined by single-crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

The article discusses a study which examines the isolation of anthocyanins from red flowers of Camellia reticulata. Spectroscopic analysis revealed the molecular structures of the anthocyanins. The chemotaxonomic distribution of the accumulated anthocyanins in the petals of wild Camellia reticulata and C. pitardii var. yunnanica was examined.

Six robust intermetallic compounds with cations in three different tunnel-like structures have been synthesized in alkali-metal-Au-In systems via high-temperature solid-state methods and characterized by X-ray diffraction: AAu4-In6 [A = K (I), Rb (II), P6m2, Z = 1], K1.76(6)Au6In4 (III, I4/mcm, Z = 4), and AxAu2In2 [x ≈ 0.7, A = K (IV), Rb (V), Cs (VI), P42/nmc, Z = 8]. The first type is constructed from a single cage unit: an alkali-metal-centered 21-vertex polyhedron A@Au9In12 with 6-9-6 arrangement of planar rings. The others contain uniaxial arrays of tunnels built of differently puckered eight- and four-member Au/In rings. The largely different cation distributions depend on the tunnel constitutions and cation sizes. Tight-binding electronic structure calculations by linear muffin-tin-orbital (LMTO) methods were performed for I and idealized III in order to help understand their chemical bonding. These also reveal large differences in relativistic effects for Au d orbitals, as well as for different Au sites in each structure. [ABSTRACT FROM AUTHOR]

Excitation energies, magnetic dipole, and electric quadrupole transition probabilities of the transition in the potassium-like (K-like) sequence with are investigated by using the multi-configuration Dirac–Hartree–Fock (MCDHF) method. The contributions of the electron correlations, Breit interaction, and the leading-order quantum electrodynamic (QED) effects on the transition properties are analyzed. The present results are interested in the laboratory tokamak and the astronomical observations. Furthermore, the feasibility of these ions for the highly charged ion (HCI) clocks is discussed. Considering the wavelength of lasers and manipulation process of the atomic clocks, Cu10+ and Zn11+ are recommended as promising candidates with achievable quality factors at the 1015 level. [ABSTRACT FROM AUTHOR]

The molecular structures of ethyl 5-amino-3-(4,6-dimethylpyrimidin-2-ylamino)-1-methyl-1H-pyrazole-4-carboxylate, C13H18N6O2, (I), and ethyl 5-amino-3-(4,6-dimethylpyrimidin-2-ylamino)-1-(2-nitrophenylsulfonyl)-1H-pyrazole-4-carboxylate, C18H19N7O6S, (II), have been determined. There are two intramolecular N—H…O bonds and one intermolecular N—H…O hydrogen bond in (I). The rings formed by the N—H…O hydrogen bonds are almost planar. In (II), three intramolecular N—H…O hydrogen bonds exist. [ABSTRACT FROM AUTHOR]

In the title compound, [Cu2Br2(C16H11BrN2)2] n, each Cu atom displays a distorted tetra­hedral coordination formed by three Br atoms and one N atom from 5-(4-bromo­phen­yl)-2-(4-pyridin­yl)pyridine. Each Br atom bridges three Cu atoms, forming a stair-like structure along the b axis. [ABSTRACT FROM AUTHOR]

Abstract: Early indica rice was chemically modified via acetylation to make modified food starch products with high contents of resistant starch. High contents of RS4 (type 4 resistant starch) of the products were measured. The result showed that the RS4 content increased obviously via acetylation. Acetylated starch was studied by FT-IR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), XRD (X-ray diffraction) and DSC (differential scanning calorimetry). The starch granules were destroyed as observed by SEM. The X-ray diffraction data showed that the crystal structure of acetylated starch with low degree of substitution changed slightly and a part of crystallite structure (2θ 18°) was destroyed when the acetyl content was more than 3.25%. The heat of crystalloid fusion, gelatinization temperature, and gelatinization enthalpy all decreased (DSC) as the degree of substitution increased. SEM, XRD and DSC indicated that the resistance to enzymatic degradation of acetylated starch depended on the degree of substitution and the integrity of starch granules. [Copyright &y& Elsevier]

Two novel diimine rhenium(I) carbonyl complexes with the formula [Re(CO)3(L)Br], where L = 1-(4-5′-phenyl-1,3,4-oxadiazolylbenzyl)-2-pyridinylbenzoimidazole (1) and 1-(4-carbazolylbutyl)-2-pyridinylbenzoimidazole (2), have been successfully synthesized and characterized by elemental analysis, ¹H NMR, and IR spectra. Their electrochemical, photophysical, and electroluminescent behaviors, along with the X-ray crystal structure analysis of 2, are also described. White electrophosphorescent devices were fabricated using 1 and 2 as emitters. The devices based on carbazole-containing (hole-transporting group) 2 with the structure lTO/m-MTDATA (30 nm)/NPB (20 nm)/2:CBP (8%, 30 nm)/Bphen (20 nm)/Alq3 (20 nm)/LiF (0.8 nm)/Al (200 nm) exhibit Commission lnternationale de L'Eclairage coordinates of x = 0.34, y = 0.33 with a maximum brightness of 2300 cd/m² at 580 mA/cm². When a brightness of 1500 cd/m² appears at 230 mA/cm², the devices based on 10 wt % 2 still possess 56% of the maximum efficiency which appeared at 2.7 mA/cm². These performances are among the best reported for devices using Re(I) complexes as emitters. By comparison of the electroluminescent properties of the devices based on 1 and 2, we conclude that the introduction of the carbazole group into the ligand improves the performance of 1-doped devices. [ABSTRACT FROM AUTHOR]

The development of a simple and reproducible route to prepare uniform core@TiO2 structures is urgent for realizing multifunctional responses and harnessing multiple interfaces for new or enhanced functionalities. Here, we report a versatile kinetics-controlled coating method to construct uniform porous TiO2 shells for multifunctional core-shell structures. By simply controlling the kinetics of hydrolysis and condensation of tetrabutyl titanate (TBOT) in ethanol/ammonia mixtures, uniform porous TiO2 shell core-shell structures can be prepared with variable diameter, geometry, and composition as a core (e.g., α-Fe2O3 ellipsoids, Fe3O4 spheres, SiO2 spheres, graphene oxide nanosheets, and carbon nanospheres). This method is very simple and reproducible, yet important, which allows an easy control over the thickness of TiO2 shells from 0 to ~25, ~45, and ~70 nm. Moreover, the TiO2 shells possess large mesoporosities and a uniform pore size of ~2.5 nm, and can be easily crystallized into anatase phase without changing the uniform core-shell structures. [ABSTRACT FROM AUTHOR]

Six cadmium(II) complexes containing the N2O2donor tetradentate asymmetrical Schiff base ligand 2-{[2-(dimethylamino)ethylimino]methyl}-6-methoxyphenol (HL5), namely, [(Cd3L52Cl4)2]·CH3OH·H2O (1), [Cd(L5)Cl]2·CH3OH (2), [Cd2(HL5)Cl4]n(3), {[Cd3(H2L5)2Cl8]·2H2O}n(4), [(H2L5)2]2·[CdCl4]2−·H2O (5), and [(H2L5)2]2·[CdCl4]2−(6), have been synthesized using cadmium(II) chloride and the asymmetrical Schiff base ligand HL5under different pH conditions at room temperature. The diverse structures show the marked sensitivity of the structural chemistry of the tetradentate asymmetrical Schiff base ligand HL5. Complex 1formed at pH = 10 exhibits a rare zero-dimensional structure of trinuclear cadmium(II). At pH = 8−9, a dinuclear cadmium(II) complex 2is formed. The reaction at pH = 5−7 leads to two one-dimensional structures of 3and 4. A further decrease of the pH to 3−5 results in a zero-dimensional structure 5. Owing to the departure of lattice water molecules in the crystal, complex 5at room temperature can gradually undergo single-crystal-to-single-crystal transformation to result in complex 6.The results further show that conversions of complex 1−5can also be achieved by adjusting the pH value of the reaction solution, 1→ 2pH=8→ 5pH=3and 3→ 4pH=5. Comparing these experimental results, it is clear that the pH plays a crucial role in the formation of the resulting structures, which simultaneously provides very effective strategies for constructing the CdIIcompounds with N2O2donor tetradentate asymmetrical Schiff base ligand. The strong fluorescent emissions of the six compounds (1−6) make them potentially useful photoactive materials. Furthermore, six Schiff base cadmium complexes (1−6), with 2,2-dipheny1-1-picrylhydrazy1 (DPPH) as a co-oxidant exhibited the stronger scavenging activity. [ABSTRACT FROM AUTHOR]

A series of molybdenum/tungsten polyoxometalate compounds, namely, [(MII(HL)2)Mo3O10] (M = Mn (1), Co (2), Ni (3)), [CuII2(L)2(HL)2]2(Mo8O26) (4), [Zn(HL)2(MoO4)]2·HL·4H2O (5), [CuII4(L)6WO4)]·3H2O (6) (HL = 3-(2-pyridyl)pyrazole), were designed and synthesized under hydrothermal conditions. X-ray diffraction analyses reveal that compounds 1−3have an isostructural wavelike chain structure consisting of the asymmetric building blocks of [Mo3O10], in which the ratio of octahedron {MoO6} and square pyramid {MoO5} is 1:2. The hexacoordinated transitional metal cation, just like one “anchor” to fix the above wavelike chain, is linked by two terminal oxygen atoms belonging to two edged asymmetric molybdate [Mo3O10]2−units, and further chelated by two 3-(2-pyridyl)pyrazole ligands. Although a similar synthetic method in preparation of 1−5was employed, compounds 4and 5show a completely different structure compared to compounds 1−3. Compound 4is composed of two separate parts of the [CuII2(L)2(HL)2]2+dimer and the ε-[Mo8O26]4−unit. Compound 5consists of a bimetallic tetranuclear cluster that is constructed from corner-sharing {MoO4} tetrahedra and {ZnN4O2} distorted octahedron forming a cyclic {Zn2Mo2O4} core. For compound 6, a one-dimensional structure is composed of WO42−linked by the centrosymmetric tetranuclear copper grids, in which two approximately planar [CuII(L)]2units with an inversion center stack parallel and face-to-face linked by two additional deprotonated ligands of L−1perpendicularly. [ABSTRACT FROM AUTHOR]

Thermal treatment of indenyl-functionalized imidazolium salts and N-heterocyclic carbenes with Ru3(CO)12gave different products. The normal mononuclear metal complexes (2a, 2b) were obtained viadirect reaction of indenyl-functionalized imidazolium salts (1a, 1b) with Ru3(CO)12. Unexpected intramolecular C–H activated products (3a, 3b, 4a, 4b) were obtained viathermal treatment of corresponding indenyl-functionalized N-heterocyclic carbenes. All complexes were determined by 1H NMR, 13C NMR, IR spectra and elemental analysis. The molecular structures of 2b, 3a, 3band 4bwere determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The article deals with a study which synthesized a paddlewheel-based polymer obtained from a novel multifunctional zwitterionic dicarboxylate ligand. The geometrical structure of the paddlewheel clusters is described. It illustrates the interactions between benzene rings of benzimidazole groups. Also noted is the crystal structure of the benzene rings of the ligands.

In the title complex, (C8H20N)2[Cu(C3S5)2], each Cu atom is tetracoordinated by four dmit S atoms (dmit is 2-thio­xo-1,3-di­thiole-4,5-di­thiol­ate), forming a slightly distorted square-planar arrangement. The average Cu—S bond length is a little larger than the sum of the single-bond covalent radii. The S—Cu—S bond angles for the vicinal S atoms are somewhat larger than the typical right angle and the other two angles are much smaller than 180°. The [Cu(dmit)2]2− anions and tetraethyl­ammonium counter-cations form a layered arrangement in the crystal structure. [ABSTRACT FROM AUTHOR]

The title compound, C13H6O4S5, possesses crystallographically imposed mirror symmetry, with the atoms of the C=S group lying on the mirror plane. It is an example of the general formula [ RCO]2(dmit), where R is a furan ring and dmit is 2-thioxo-1,3-dithiole-4,5-dithiol­ate. The components exhibit some polarization of their mol­ecular–electronic structure. The dmit and furan moieties exhibit a high degree of conjugation, as the introduction of C=O connecting the conjugated furan (donor) and dmit (acceptor) rings forms a good conjugated system with high delocalization. A polar three-dimensional framework is built from a combination of inter­molecular contacts, namely S⋯S inter­actions and C—H⋯O hydrogen bonding. The structural characteristics lead to good second-order non-linear optical properties. [ABSTRACT FROM AUTHOR]