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Organic molecules bearing chiral sulfur stereocenters exert a great impact on asymmetric catalysis and synthesis, chiral drugs, and chiral materials. Compared with acyclic ones, the catalytic asymmetric synthesis of thio‐heterocycles has largely lagged behind due to the lack of efficient synthetic strategies. Here we establish the first modular platform to access chiral thio‐oxazolidinones via Pd‐catalyzed asymmetric [3+2] annulations of vinylethylene carbonates with sulfinylanilines. This protocol is featured by readily available starting materials, and high enantio‐ and diastereoselectivity. In particular, an unusual effect of a non‐chiral supporting ligand on the diastereoselectivity was observed. Possible reaction mechanisms and stereocontrol models were proposed. [ABSTRACT FROM AUTHOR]

Organic molecules bearing chiral sulfur stereocenters exert a great impact on asymmetric catalysis and synthesis, chiral drugs, and chiral materials. Compared with acyclic ones, the catalytic asymmetric synthesis of thio‐heterocycles has largely lagged behind due to the lack of efficient synthetic strategies. Here we establish the first modular platform to access chiral thio‐oxazolidinones via Pd‐catalyzed asymmetric [3+2] annulations of vinylethylene carbonates with sulfinylanilines. This protocol is featured by readily available starting materials, and high enantio‐ and diastereoselectivity. In particular, an unusual effect of a non‐chiral supporting ligand on the diastereoselectivity was observed. Possible reaction mechanisms and stereocontrol models were proposed. [ABSTRACT FROM AUTHOR]

Metal‐polarized aza‐ortho‐quinone methides (aza‐o‐QMs) are a unique and efficient handle for azaheterocycle synthesis. Despite great achievements, the potential of these reactive intermediates has not yet been fully exploited, especially the new reaction modes. Herein, we disclosed an unprecedented dearomatization process of metal‐polarized aza‐o‐QMs, affording transient dearomatized spiroaziridine intermediates. Based on this serendipity, we accomplished three sequential dearomatization‐rearomatization reactions of benzimidazolines with aza‐sulfur ylides, enabling the divergent synthesis of bis‐nitrogen heterocycles with high efficiency and flexibility. Moreover, experimental and theoretical studies were performed to explain the proposed mechanisms and observed selectivity. Further cellular evaluation of the dibenzodiazepine products identified a hit compound for new antitumor drugs. [ABSTRACT FROM AUTHOR]

Metal‐polarized aza‐ortho‐quinone methides (aza‐o‐QMs) are a unique and efficient handle for azaheterocycle synthesis. Despite great achievements, the potential of these reactive intermediates has not yet been fully exploited, especially the new reaction modes. Herein, we disclosed an unprecedented dearomatization process of metal‐polarized aza‐o‐QMs, affording transient dearomatized spiroaziridine intermediates. Based on this serendipity, we accomplished three sequential dearomatization‐rearomatization reactions of benzimidazolines with aza‐sulfur ylides, enabling the divergent synthesis of bis‐nitrogen heterocycles with high efficiency and flexibility. Moreover, experimental and theoretical studies were performed to explain the proposed mechanisms and observed selectivity. Further cellular evaluation of the dibenzodiazepine products identified a hit compound for new antitumor drugs. [ABSTRACT FROM AUTHOR]

Three interpenetrating Co(II)/Ni(II) coordination polymers, [Co(pytpy)(sfdb)] n ( 1 ), [Co 2 (pytpy)(sfdb) 2 ] n ( 2 ) and [Ni(pytpy)(sfdb)] n · nH 2 O ( 3 ) (pytpy = 4'-(4-pyridyl)-4,2':6′,4″-terpyridine, H 2 sfdb = 4,4′-sulfonyldibenzoic acid) have been hydrothermally synthesized and structurally characterized. They all feature interpenetrating 3D honeycomb networks. Compound 1 is a 4-fold 3D polymeric structure, bidentate-bridging pytpy ligands join the square wave-like chains based on Co(II) centers and μ 2 -sfdb 2- linkers to form the final 3D honeycomb network. Compound 2 is also a 3D honeycomb structure, which features 2-fold interpenetrating structure with unusual paddle-wheel secondary building units (SBUs). The topological net of compound 3 is identical to 1 , but the central metal and its coordination environment are different from those of compound 1 . In addition, diffuse reflectance UV–vis spectroscopic measurements and thermal gravimetry analyses have been used to characterize these compounds. [ABSTRACT FROM AUTHOR]

A novel copper-catalyzed decarboxylative cyclization of ethynyl benzoxazinanones with P(O)H compounds has been developed. This protocol leads to a series of 2-phosphorylmethyl indoles with high efficiency and selectivity (up to 99% yield) through tandem C–P/C–N bond formation under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: Two novel Zn(II) coordination polymers, [Zn(2-pytpy)(fum)] n ·nH2O (1) and [Zn6(4-pytpy)3(mal)4] n ·5n(H2O) (2), (2-pytpy=4′-(4-pyridyl)-2,2′:6′,2″-terpyridine, 4-pytpy=4′-(4-pyridyl)-4,2′:6′,4″-terpyridine, H2fum=fumaric acid and H2mal=malic acid) have been hydrothermally synthesized and structurally characterized. Notably, in situ ligand reactions occur in the formation of complexes 1 and 2, in which maleic acid is converted into fumaric acid and malic acid, respectively. Complex 1 is a 1D infinite chain structure, which is extended into a supramolecular layer by intermolecular π…π stacking interactions. Complex 2 is a 3D network structure, in which the bidentate-bridging 4-pytpy ligands link the layers based on the tetranuclear Zn(II) subunits to form the (4,10)-connected network. The luminescent properties of 1 and 2 have been investigated with emission spectra and UV–Vis diffuse reflectance spectra in the solid state. Additionally, these two complexes possess great thermal stabilities. [ABSTRACT FROM AUTHOR]

Abstract: Two novel Zn(II) coordination polymers, [Zn5(pytpy)8(fum)4(H2O)4(OH)2] n · n(CH3OH)·2n(H2O) (1) and [Zn3(pytpy)4 (btc)2] n ·2n(H2O) (2) (pytpy=4′-(4-pyridyl)-3,2′:6′,3″-terpyridine, H2fum=fumaric acid, H3btc=1,3,5-benzenetricarboxylic acid) have been hydrothermally synthesized and structurally characterized. Complex 1 is a 2D layer structure, which is constructed from linear pentanuclear Zn(II) subunits interconnected via bidentate-bridging pytpy ligands and tridentate-bridging fum2− anions. Complex 2 is a 3D network structure, μ2-pytpy ligands link the layers based on the heart-like hexanuclear subunits to form the 3D network. Both complexes show strong fluorescence emission upon excitation at 310nm in solid state. Additionally, these two complexes possess great thermal stabilities, especially for 2, the framework is stable up to 350°C. [Copyright &y& Elsevier]

Abstract: The electrochemical behaviors of passive film of stainless steel 0Cr13Ni5Mo under the condition of static state (quiescence) and ultrasonic cavitation in the HCl solution have been studied by means of polarization curve, electrochemical impedance spectroscopy (EIS) and capacitance potential measurement. The results indicate that the passive film shows a multi layer structure distribution, and presents a p-type semiconductor property under the condition of quiescence. The stability of passive film decreases, the semiconducting property changes to an n-type semiconductor in the presence of cavitation. The amount of transition electrons from valence band because of cavitation is related to the height of Fermi level of passive film semiconductor. [Copyright &y& Elsevier]

Abstract: Regardless of the well-documented virilis species group, most groups of the Drosophila virilis section have not been completely studied at molecular level since it was suggested. Therefore, phylogenetic relationships among and within species groups of the virilis section are generally unknown. In present paper, the complete mitochondrial ND2 gene and fragment of COI gene in combination with a nuclear gene, Adh coding region, were used to derive the most extensive molecular phylogeny to date for the Drosophila virilis section. A total of 111 individuals covering 61 species were sampled in this study. Novel phylogenetic findings included (1) support for the paraphyly of the melanica and robusta species group and at least two subgroups of the robusta species group, the lacertosa and okadai subgroups, were distinguished as paraphyletic taxa. In addition, (2) present results revealed the sister relationship between D. moriwakii and the robusta subgroup, conflicting with current taxonomy regarding D. moriwakii, which was shifted from the robusta species group to the melanica group. (3) In contrast to the robusta and melanica species groups, monophyly of the polychaeta species group, the angor group and the virilis group was confirmed, respectively. However, the monophyletic quadrisetata species group was resolved with uncertainty. (4) Our analyses of combined data set suggested close relationship between the quadrisetata species group and the unpublished clefta group, and the okadai subgroup is sister to the clade comprising of the quadrisetata and clefta species groups. Within the virilis section, D. fluvialis and three tropical species groups, the polychaeta group, the angor group and the repleta group, are found to branch off earlier than other ingroup taxa. This suggests that the virilis section might have originated in the Old World tropics. Besides, the derived status of the close affinities of the quadrisetata group, the clefta group, and the melanica and robusta groups is probably the result of their adaptation to forests between subtropical and cool-temperate climate. Based on the consideration of the phylogenetic placement of the species of the virilis section, we suggest that at least five independent migrations occurred from the Old World to the New World. [Copyright &y& Elsevier]

Nd3+:Er3+:Yb3+codoped Al2O3powder is prepared by the nonaqueous sol-gel method and pressed into a small wafer. The two-stage sensitization processes for energy transfer among Yb3+, Er3+, and Nd3+are discussed. Under a 978-nm semiconductor laser excitation, the photoluminescence intensities at 813 and 887 nm, corresponding to the 4F52+2H92→4I92and 4F32→4I92transitions of Nd3+ions, enhance monotonously with the increasing temperature, and the fluorescence intensity ratio of the near-IR emissions can be fitted the exponential function R=3.12 exp(−1150T)in the temperature range of 375 to 889 K. The maximum sensitivity is 0.0015 K−1at 574.3 K. The data are of undoubted repeatability, and the material is applicable for sensitive, high-temperature measurement. [ABSTRACT FROM AUTHOR]

Although decidualization is crucial for the establishment of successful pregnancy, the molecular mechanism underlying decidualization remains poorly understood. Crystallin αB (CryAB), a small heat shock protein (sHSP), is up-regulated and phosphorylated in mouse decidua. In mouse primary endometrial stromal cells, CryAB is induced upon progesterone treatment via HIF1α. In addition, CryAB is strongly phosphorylated through the p38-MAPK pathway under stress or during in vitro decidualization. Knockdown of CryAB results in the increase of apoptosis of stromal cells and inhibits decidualization under oxidative or inflammatory stress. Our data indicate that CryAB protects decidualization against stress conditions. [ABSTRACT FROM AUTHOR]

Five zinc(II) metal–organic frameworks, [Zn3(344-pytpy)2Cl6] n · n(H2O) (1), [Zn(344-pytpy)(ox)] n (2), [Zn2(344-pytpy)(bdc)2] n ·1.5n(H2O) (3), [Zn2(344-pytpy)2 (sfdb)2] n ·1.5n(H2O) (4) and [Zn3(344-pytpy)2(btc)2] n ·2n(H2O) (5), (344-pytpy=4′-(3-pyridyl)-4,2′:6′,4″-terpyridine, H2ox=oxalic acid, H2bdc=1,4-benzenedi-carboxylic acid, H2sfdb=4,4′-sulfonyldibenzoic acid and H3btc=1,3,5-benzene-tricarboxylic acid) have been prepared by hydrothermal reactions. Compound 1 is a 1D chain structure, in which 344-pytpy ligand links three ZnII centers through three of terminal N-donors. Compound 2 is a 4-connected 3D framework with the dia topological net and the Schläfli symbol of 66. Compound 3 displays a unusual 3-fold interpenetrating 3D coordination network which exhibits a new intriguing (3,3,4)-connected topological net with the Schläfli symbol of (4.82)(4.85)(83). Compound 4 features a two-fold interpenetrating 4-connected 2D framework with the sql topological net and the Schläfli symbol of (44.62). Compound 5 is a new self-interpenetrating (3,3,4,4)-connected topological net with the Schläfli symbol of (6.82)2(62.82.10.12)(62.83.10)2(62.8)2. The luminescence properties of 1–5 have been investigated by emission spectra and they possess great thermal stabilities which can be stable up to around 400°C. [ABSTRACT FROM AUTHOR]

Abstract: Five structurally diverse complexes, [Cd2(pyip)2(suc)2] n ·1.5nH2O (1), [Zn(pyip)(glu)] n (2), [Cd(pyip)(glu)] n (3), [Zn(pyip)2(adip)2] n ·2.5nH2O (4), [Cd3(pyip)2(adip)3] n (5) (pyip=2-(pyridin-3-yl)-1H-imidazo[4,5-f][1,10]phenan-throline, H2suc=succinic acid, H2glu=glutaric acid, H2adip=adipic acid), have been hydrothermally synthesized. Complexes 1 and 4 are ribbon-like chains, in which pyip ligands attach to the both sides of the chain in pairs. Complex 2 is a one dimensional (1D) wave-like chain, while the pyip ligands attach to only one side of the chain. Complexes 3 and 5 are both two dimensional (2D) networks, in which the dicarboxylate ligands connect the dinuclear or trinuclear CdII units into layers with (4,4) topological network. The structural differences among these complexes show that the organic acids have important influences on the final structures. [ABSTRACT FROM AUTHOR]

Abstract: Two novel cadmium(II) coordination polymers [Cd(cptpy)2] n ·nH2O (1) with a 1D double chain structure and [Cd2(cptpy)2(ox)] n ·2.5nH2O (2) with an interesting 3-connected uninodal six-fold interpenetrating ths network (Hcptpy=4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine, H2ox=oxalic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, single crystal X-ray diffraction and fluorescence spectra. [Copyright &y& Elsevier]

Abstract: Using the principle of crystal engineering, six metal-organic coordination polymers, [Cd(bdc)(3-pytpy)] n ·2nH2O (1), [Cd(bdc)0.5(3-pytpy)] n · n(ClO4) (2), Cd(ndc)0.5(3-pytpy)] n · n(ClO4) (3), [Zn(ndc)(3-pytpy)] n (4), [Cd(bqdc)(3-pytpy)] n (5), and [Zn(pam)(3-pytpy)] n ·2nH2O (6) (H2bdc=benzene-1,4-dicarboxylic acid, H2ndc=naphthalene-2,6-dicarboxylic acid, H2bqdc=2,2′-biquinoline-4,4′-dicarboxylic acid, H2pam=pamoic acid), were synthesized and structurally characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analyses. Compounds 1–6 crystallize in the presence of organic-acid linkers as well as multi-functional N-donor ligand 4′-(3-pyridyl)-2,2′:6′,2′′-terpyridine (3-pytpy). In complexes 1, 4, 5, and 6, the dicarboxylate as bridging ligand connects metal atoms to form the main body of 1D zigzag chains for 1 and 4, nearly linear chain for 5 and helical chain for 6, while 3-pytpy as tridentate chelating ligand is just like lateral arm grafting on both sides of these chains. In complexes 2 and 3, both the dicarboxylate and 3-pytpy as bridging ligands connect metal atoms into 2D polymeric structure for 2 and 1D chain of alternating loops and rods for 3. The weak interactions such as hydrogen bonding and π···π stacking were investigated on the formation of superamolecular structures and the influence of organic acid on the formation of the final structures was discussed. In addition, the photoluminescent properties of 1–6 were also determined. [Copyright &y& Elsevier]

Two metal-organic coordination polymers, [Cd(HIDC)(pytpy)] (1) and [Zn(HIDC)(pytpy)] · (H2O) (2), have been synthesized by reactions of 4'-(3-pyridyl)-2,2' : 6',2''-terpyridine (pytpy), 4,5-imidazoledicarboxylic acid (H3IDC) with CdCl2 · 2.5H2O and ZnCl2, respectively, in the presence of base. Compound 1 is a one-dimensional (1-D) helical chain with the chains extended into a three-dimensional supramolecular network through two different π ··· π interactions from pytpy ligands. Compound 2 is also a 1-D helical chain and adjacent chains are packed into a 2-D layer through π ··· π interactions between terminal pyridyl and pendant pyridyl rings from pytpy ligands. The photoluminescent properties of the two compounds are also investigated. [ABSTRACT FROM AUTHOR]

Abstract: Two new co-crystal copper(II) melamine complexes, [Cu(HBA)2(MA)2] [Cu(HBA)2] (1) and [Cu2(OAc)4(MA)·(H2O)]2[Cu(HPE)2] (2), MA, melamine; HBA, 2-hydroxybenzaldehyde; HPE, 1-(2-hydroxyphenyl)ethanone, have been synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction. Crystal structural analysis reveals that 1 and 2 all are co-crystal complexes and composed of two neutral coordination units. In 1, two mononuclear units adopt square planar and distorted octahedral coordination environments, respectively. In 2, one is a mononuclear unit with a square planar geometry and the other is a dinuclear unit with a paddle wheel structure in which the apical positions are rarely occupied by two different donor ligands. The 2D supramolecular structures are formed through strong hydrogen bonds with different modes. The electrochemical behaviors of complexes 1 and 2 were investigated. [Copyright &y& Elsevier]

Abstract: Two metal-organic coordination polymers, [Cd(dpa)(pytpy)]·(H2O)3 (1) and [Cd3(dpa)(pytpy)2(SO4)2]·(H2O)3 (2), have been synthesized by the reactions of 4′-(3-pyridyl)-2,2′:6′,2′′-terpyridine (pytpy), diphenic acid (H2dpa) with Cd(ClO4)2·6H2O and CdSO4·8/3H2O, respectively, in the presence of base. Compound 1 is a one-dimensional helical chain, in which (dpa)2− as bridging ligand is responsible for the formation of the main framework and pytpy as chelating ligand grafts on one side of the helical chain and forms π–π stacking interactions with adjacent chains. This compound is further extended into a two-dimensional supramolecular framework through hydrogen bonds. Compound 2 is a one-dimensional chain simultaneously composed of bridging neutral organic ligand, bridging anionic organic ligand and bridging anionic inorganic ligand. The (dpa)2− and sulfate anions connect CdII atoms into neutral [Cd3(dpa)(SO4)2] subunits and the trinuclear units are bridged by pytpy ligand into one-dimensional double-layer chain. This structure is further extended into two-dimensional layer architecture through face-to-face π–π interactions. [Copyright &y& Elsevier]