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A series of lanthanide boroantimonates, namely, LnBSb2O8 (Ln = Sm 1, Eu 2, Gd 3, and Tb 4) have been successfully synthesized by high temperature solid-state reactions for the first time. They are isostructural and feature novel three-dimensional (3D) frameworks composed of 2D [Sb3O12]9– layers interconnected by 1D [SbBO7]6– chains with remaining BO3 groups hanging on the walls of the 1D 6-membered-ring (MR) tunnels along the a-axis, and the lanthanide ions filled in the voids of the anionic structure. They exhibit high thermal stability (up to 900 °C). Luminescent studies suggest that compounds 1, 2, and 4 have potential application as orange, red, and green light luminescent materials, respectively. Magnetic measurements reveal ferromagnetic coupling interactions in compound 3 and antiferromagnetic coupling interactions between magnetic centers in compounds 1, 2, and 4.

Graphite oxide (GO) was used as a catalyst for the reactions of alcohols and phenols with acetic anhydride. The acetates of primary and secondary alcohols were prepared in good to excellent yields in short reaction time under mild conditions. Electron deficient phenols could be converted to the corresponding acetates steadily. As an efficient catalyst, GO is easily available, cheap, moderately toxic and weakly acidic.

A novel method for the synthesis of diversely functionalized pyrazolo[5,1-a]isoindol-8(3aH)-ones is developed via phosphine-catalyzed tandem Michael addition/intramolecular Morita–Baylis–Hillman reaction of electron-deficient alkynes and N-amino substituted phthalimide. This cyclization is operationally simple under metal-free reaction conditions.

A pair of new enantiomeric alkaloid dimers, (+)- and (−)-pestaloxazine A (1), with an unprecedented symmetric spiro[oxazinane-piperazinedione] skeleton, consisting of 22 carbons and 12 heteroatoms, were isolated from a Pestalotiopsis sp. fungus derived from a soft coral. Separation of the enantiomeric alkaloid dimers was achieved by chiral HPLC. Their structures including absolute configurations were elucidated on the basis of a comprehensive analysis of their spectroscopic and X-ray diffraction data and CD calculations. (+)-Pestaloxazine A exhibited potent antiviral activity against EV71 with an IC50 value of 14.2 ± 1.3 μM, which was stronger than that of the positive control ribavirin (IC50 = 256.1 ± 15.1 μM).

A highly efficient asymmetric 1,3-dipolar cycloaddition of azomethine ylides to 5-alkylidene thia(oxa)zolidine-2,4-diones catalyzed by a chiral N,O-ligand/Cu(CH3CN)4BF4 system is reported, affording structurally novel spirocyclic pyrrolidine-thia(oxa)zolidinediones with a spiro-heteroquaternary stereogenic center in good to excellent yields (up to 99%), with excellent levels of diastereo- and enantioselectivity (dr up to 99:1; ee up to 98%).

A new method has been developed for the copper(I)-mediated trifluoromethylthiolation of α-bromoketone using commercial anhydrous potassium fluoride, elemental sulfur, and (trifluoromethyl)-trimethylsilane in anhydrous N , N -dimethylformamide. This protocol provides facile access to a variety of α-trifluoromethylthiolated carbonyl compounds in moderate to excellent yields under mild and ligand free conditions.

A convenient process is described to convert a variety of allylic chlorides into allylic trifluoromethyl thioethers.

Highly stereoselective intermolecular reactions of electron-deficient alkynes with N-hydroxyphthalimides for efficient construction of N-unprotected 3-methyleneisoindolin-1-ones have been developed through base catalytic strategies. The reaction of alkynoates with N-hydroxyphthalimides catalyzed by Bu3P in DMF at 150 °C gave the corresponding 3-methyleneisoindolin-1-ones with a (Z)-configuration, while the reaction of alkynoates with N-hydroxyphthalimides catalyzed by K2CO3 in DMF at 60 °C gave the corresponding 3-methyleneisoindolin-1-ones with an (E)-configuration, and (Z)-3-methyleneisoindolin-1-ones were obtained when alkyne ketones reacted with N-hydroxyphthalimide.

Surface-modified titanium dioxides by highly dispersed NiO particles have an extended absorption in the visible light region and a reduced hole–electron pair recombination than unmodified TiO2. They have now been successfully applied as highly active heterogeneous photocatalysts in the visible light mediated direct cyclization of tertiary anilines with maleimides to give tetrahydroquinoline products in moderate to high yields at ambient temperature. In contrast with unmodified titanium dioxide catalysts that are conventionally used in a stoichiometric amount in combination with UVA light, only a catalytic amount (1 mol %) of the surface-modified TiO2 catalyst is needed along with visible light to efficiently catalyze the reaction. Compared with transition-metal complexes such as Ru(bpy)3Cl2 or Ir(ppy)2(dtbbpy)PF6, advantages of these surface-modified titanium dioxides as photocatalyst include high catalytic activity, low cost, ease of recovering, and being able to be used for at least nine times without s...

Eight novel daphnane-type ditepenes, neogenkwanines A—H, are isolated along with seven known ones.

[Ln(H2O)5] 2Mo6V2O26·8H2O (Ln: La, Ce, Nd) are prepared by the reaction of [Mo6V2O26]6- with Ln(NO3)3 in aqueous solution at pH 3 (80 °C, 1 h).

When primary and secondary amines are used in excess, they react with N-sulfonyl aziridines, mainly affording 1:1 ring opening products (III), (V), (XI).

A new photoinduced three-component reaction between a cyanoarene, an alkene and an N-protected pyrrole has been developed. This reaction extended the scope of the photo-NOCAS reaction by introducing pyrrole as a neutral carbon-centered nucleophile. The cyanoarenes used include tetracyanobenzene (TCB), 2,3,5,6-tetrafluoro-1,4-dicyanobenzene (TFDCB) and 1,4-dicyanobenzene (DCB). N-Methyl, N-phenyl and N-Boc pyrroles are suitable nucleophiles in the reaction. Taking advantage of the strong electron acceptor ability of the singlet excited TCB, a wide range of alkenes, including the highly electron deficient 4-fluoro-, 4-chloro-, 2,3,4,5,6-pentafluorostyrenes and N-methylmaleimide take part in this reaction, leading to the simultaneous 1,2-diarylation of the alkene and the regioselective 2-alkylation of the pyrrole ring via sequential formation of two new C–C bonds between the three reactants.

Reduced graphene oxide efficiently catalyzes the aerobic oxidative dehydrogenation of aromatic hydrazo compounds.

The products are of high biological importance and are prepared in high yields under mild conditions from readily available substrates.

Nine new 8-O-4' neolignans, named pinnatifidanin B I-IX (1-9), together with 9 known analogs (10-18) were isolated from the seeds of Crataegus pinnatifida. The structures of 1-18 were determined by spectroscopic methods, including 1D, 2D NMR, CD and HRESIMS analysis. Compounds 8-11, 17 and 18 displayed potent cytotoxic activities against human cancer cell lines, and most interestingly, none of the 6 compounds displayed inhibitory activity against human lung cell line (Mrc5). The 6 cytotoxic compounds are considered to be potential as antitumor agents, which could significantly inhibit the cancer cell growth in a dose-dependent manner and are probably safer than positive control drug.

Four new daphnane-type diterpenes, genkwadanes A-D (I)—(IV), resp., are isolated along with 19 known compounds from the flower buds of Daphne genkwa.

Graphite oxide (GO) has attracted much attention of material and catalysis chemists recently. Here we describe a combination of GO and molecular sieves for the dehydrogenative aromatization. GO prepared through improved Hummers method showed high oxidative activity in this reaction. Partially or fully saturated aromatic compounds were converted to their corresponding dehydrogenated aromatic products with fair to excellent conversions and selectivities. As both GO and molecular sieves are easily available, cheap, lowly toxic and have good tolerance to various functional groups, this reaction provides a facile approach toward aromatic compounds from their saturated precursors.

Black block-shaped crystals of [Mn2Cu(N3)6(en)2]n are synthesized by slow evaporation of solutions containing MnCl2, NaN3, Cu(NO3)2, and en in MeOH and H2O (5 °C, 7 d, 30% yield).

A simple and efficient method for the synthesis of the title compounds (III) and (V) is developed.

The catalyst system displays high efficiency in the stereoselective hydrosilylation of a wide scope of aryl alkyl and heteroaromatic ketones under an air atmosphere and mild conditions.

The same reduced products are obtained regardless whether (Z)-, (E)-isomers or isomeric mixtures are used as substrates.

We review core/shell structured magnetic carbonyl iron (CI)/polymer hybrid particles fabricated with various polymeric systems and their magnetorheological (MR) characteristics when dispersed in non-magnetic suspending medium. Their morphology and magnetization properties are compared with those from different fabrication methodologies. Rheological characteristics of the MR fluids, exhibiting improved dispersion stability compared to the pure CI based MR fluid, are presented along with their potential engineering applications.

Single crystals of the title compound are grown from mixture of Cs2CO3, Al2O3, ZrO2, and NH4H2PO4 with a Cs:Al:Zr:P molar ratio of 1.66:1:1:8 (Pt crucible, 1173 K, 20 h).

As one of the most important field-responsive intelligent and smart soft matter materials, magnetorheological (MR) fluids, consisting of magneto-responsive magnetizable particles suspended in non-magnetic fluids, have drawn a lot of attentions in both academia and industry as their physical and rheological characteristics can be controlled with external magnetic field strength. In this highlight, preparation methods and MR properties of various magnetic composites with soft magnetic particles and polymers are reviewed. In addition, some industrial applications, such as a MR dampers and a MR polishing, are briefly summarized.

High quality CuInSe2 nanocrystals with monodispersed size and uniform hexagonal shape are synthesized from mixtures of Cu-oleate (obtained by reacting CuCl2 and sodium oleate dissolved in EtOH/H2O/hexane at 70 °C for 4 h), InCl3, Ph2Se2, and oleylamine (255 °C, 1.5 h).

The 2,3-diarylpyrimido[1,2-a]benzimidazole derivatives were prepared by one-step cyclocondensation of 2-aminobenzimidazole with isoflavone in methanol. Single-crystal diffraction analysis was performed for 2-(2-hydroxyl-4-isopropoxy-phenyl)-3-phenylpyrimido[1,2-a]benzimidazole. The fluorescence properties of the fused 2, 3-diarylpyrimido[1, 2-a]benzimidazole were evaluated.

A series of N-substituted carbazole derivatives were synthesized and evaluated for antibacterial and antifungal activities against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Bacillus proteus, Candida albicans and Aspergillus fumigatus by two fold serial dilution technique. Some of the synthesized compounds displayed comparable or even better antibacterial and antifungal activities than reference drugs fluconazole, chloramphenicol and norfloxacin against tested strains.

A simple and straightforward methodology toward the synthesis of novel 4,5-biphenyl-2-pyrimidinylguanidine compounds has been developed by one-pot reaction of biguaninde or dimethyldiguanide with isoflavones. A series of 20 new compounds was reported. All of them were characterized by FT-IR, NMR, and elemental analysis. A typical compound was determined by X-ray diffraction. A variety of substrates can participate in the process with good yields and high purities, making this methodology suitable for library synthesis in drug discovery.

A new ferrocene-based ligand, 4,6-dimethyl-2-pyrimidinylferrocene (1), was conveniently prepared via the coupling reaction of chloromercuriferrocene and 4,6-dimethyl-2-iodopyrimidine, and its monop...

Four rare isoryanodane diterpenoids namely itols A–D (1–4) and two isoryanodane glucosides (5 and 6) were isolated from the bark and twigs of Itoa orientalis. Their structures were determined by NMR and MS techniques and the structure of 1 was confirmed by a single-crystal X-ray diffraction. These six diterpenoids obviously showed insecticidal activity against Spodoptera exigua, with LC50 28.62 ppm for 1 and 52.76 ppm for 2, respectively. In anti-inflammatory assay, compounds 1 and 4–6 showed anti-COX-2 activity, with inhibitory rates of 54.7–78.3% at 10 μM.

Eight new benzoylated gentisyl alcohol (=2-(hydroxymethyl)benzene-1,4-diol) glucosides, itosides A–H (1–8), together with the new pyrocatechol (=benzene-1,2-diol) glycoside itoside I (9) were isolated from the bark and twigs of Itoa orientalis (Flacourtiaceae). In itosides B–D (2–4), the gentisyl alcohol moiety was esterified by 1-hydroxy-6-oxocyclohex-2-ene-1-carboxylic acid, while itosides E–H (5–8) contained instead an additional 2-hydroxybenzoic acid moiety. The compounds were accompanied by the known derivatives 4-hydroxytremulacin (10), poliothyrsoside (11), poliothyrsin (12), homaloside D (13), tremulacin, and pyrocatechol β-D-glucopyranoside. The structures of the new compounds were elucidated by spectral and chemical methods.