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Background and aims Hepatic ischemia-reperfusion (I/R) injury, which mainly involves inflammatory responses and apoptosis, is a common cause of organ dysfunction in liver transplantation (LT). As a critical mediator of inflammation and apoptosis in various cell types, the role of tripartite motif-containing (TRIM) 27 in hepatic I/R injury remains worthy of study. Approach and results This study systemically evaluated the putative role of TRIM27/transforming growth factor β-activated kinase 1 (TAK1)/JNK (c-Jun N-terminal kinase)/p38 signaling in hepatic I/R injury. TRIM27 expression was significantly down-regulated in liver tissue from LT patients, mice subjected to hepatic I/R surgery, and hepatocytes challenged by hypoxia/reoxygenation (H/R) treatment. Subsequently, using global Trim27 knockout mice (Trim27-KO mice) and hepatocyte-specific Trim27 transgenic mice (Trim27-HTG mice), TRIM27 functions to ameliorate liver damage, reduce the inflammatory response, and prevent cell apoptosis. In parallel in vitro studies, activating TRIM27 also prevented H/R-induced hepatocyte inflammation and apoptosis. Mechanistically, TRIM27 constitutively interacted with the critical components, TAK1 and TAK1 binding protein 2/3 (TAB2/3), and promoted the degradation of TAB2/3, leading to inactivation of TAK1 and the subsequent suppression of downstream JNK/p38 signaling. Conclusions TRIM27 is a key regulator of hepatic I/R injury by mediating the degradation of TAB2/3 and suppression of downstream TAK1-JNK/p38 signaling. TRIM27 may be a promising approach to protect the liver against I/R-mediated hepatocellular damage in transplant recipients.

Two novel isomorphous 2D NiII/CoII-NiII Metal-Organic Frameworks (MOFs) with tetrazole-1-acetate ligands have been synthesized and structurally characterized. And then they were calcined in air to obtain Ni/Co3O4-doped NiO electrodes. Compared to the homometallic MOF-derived oxide, the heterometallic MOF-derived bimetal oxides presented higher coulombic efficiency, better cycle performance, larger specific capacity as lithium-ion batteries anodes.

Hepatocyte apoptosis is a crucial factor affecting liver quality in brain-dead donors. The identification of key molecular proteins involved in brain-death (BD)-induced hepatocyte apoptosis may help determine an effective method for improving the quality of livers from brain-dead donors. In this study, we used in vivo and in vitro models to investigate the role of chitinase-3-like protein 1 (CHI3L1) in promoting liver cell apoptosis after BD. Chitin was used to inhibit CHI3L1 in a rat model of BD. Macrophage polarization of THP-1 cells and hypoxia/reoxygenation (H/R) of LO-2 cells were used to mimic BD-induced cell stress in liver. We found that CHI3L1 played a vital role in promoting liver cell apoptosis. Six hours after BD, CHI3L1 expression was significantly upregulated in liver macrophages and was associated with BD-induced M1 polarization of these cells. In liver cells cultured under H/R conditions, recombinant CHI3L1 activated the protease-activated receptor 2 (PAR2)/c-June N-terminal kinase (JNK) apoptotic pathway and aggravated apoptosis. Compared with the control group, chitin particles inhibited the expression of CHI3L1 in the liver of brain dead rats, thereby reducing activation of the hepatocyte surface receptor, PAR2, and its downstream JNK/caspase-3 signaling pathway, ultimately reducing hepatocyte apoptosis. In conclusion, our results indicate that CHI3L1 relies on a PAR2/JNK-mediated mechanism to promote BD-induced hepatocyte apoptosis.

International audience; Solid solution of Hydrogen bonded networks of formula ((1-2H +)3x(2-2H +)3(1-x)([Fe(CN)6] 3-2)). nH2O, where (1-2H +) and (1-2H +) are bisamidinium H bond donor entities, have been synthetized and structurally analysed. The H bonded systems display a honeycomb-like structure, and depending on the x value, three different pavages of the (6,3) system are observed, leading to three different phases. The precise location of the H bond donor cations (2-2H +) have been performed, evidencing H bonding between adjacent cations. Thermal properties of the solid solutions have been performed.

This paper reports a highly effective method for replicating large-area micropattern devices through hybrid extrusion rolling embossing using a roller mold, wherein a thin stainless steel mold with a large-area micropattern is wrapped onto a metallic roll to form a roller mold. During the hybrid extrusion rolling embossing period, the molten polymer film is extruded and immediately pressed against the embossing roller and roller mold, which results in the molten polymer completely filling the micropattern on the surface of the roller mold. Next, the molten polymer film is cooled and wound using a conveying system equipped with highly polished rollers. Thus, a continuous polymer film with many large-area micropattern devices can be fabricated. In this study, a new hybrid extrusion rolling embossing system was designed, constructed, and tested; the basic film extrusion and rolling embossing conditions were investigated; and the thickness uniformity of the polymer films and the replication quality of the micropattern devices were measured and analyzed. The results indicate that the hybrid extrusion rolling embossing can potentially be used for continuous mass production of large-area micropattern devices.

Two new coordination complexes with tetrazole heterocycle ligands bearing acetate groups, [Co(L)2]n (1) and [Co3(L)4(N3)2·2MeOH]n (2) (L=tetrazole-1-acetate) have been synthesized and structurally characterized. Single crystal structure analysis shows that the cobalt-complex 1 has the 3D 3,6-connected (42.6)2(44.62.88.10)-ant topology. By introducing azide in this system, complex 2 forms the 2D network containing the [Co3] units. And the magnetic properties of 1 and 2 have been studied.

A novel open thermosyphon-type thermal storage unit is presented to improve design and performance of heat pipe type thermal storage unit. In the present study, tubular canisters filled with a solid–liquid phase change material are vertically placed in the middle of the thermal storage unit. The phase change material melts at 100 °C. Water is presented as the phase-change heat transfer medium of the thermal storage unit. The tubular canister is wrapped tightly with a layer of stainless steel mesh to increase the surface wettability. The heat transfer mechanism of charging/discharging is similar to that of the thermosyphon. Heat transfer between the heat resource or cold resource and the phase change material in this device occurs in the form of a cyclic phase change of the heat-transfer medium, which occurs on the surface of the copper tubes and has an extremely high heat-transfer coefficient. A series of experiments and theoretical analyses are carried out to investigate the properties of the thermal storage unit, including power distribution, start-up performance, and temperature difference between the phase change material and the surrounding vapor. The results show that the whole system has excellent heat-storage/heat-release performance.

We investigated the effect of red light and plant growth regulators on somatic embryogenesis in China Rose (Rosa chinensis Jacq.). Embryogenic calli that had been induced by combinations of 2,4-dichlorophenoxyacetic acid and thidiazuron in darkness were exposed to dark, red, and white light treatments. Cultures subjected to red light treatment generated the greatest number of embryos, with one (SE1 embryos) or two (SE2 embryos) expanded cotyledons. The largest numbers of shoot-like embryos without cotyledons (SE0 embryos) were produced in cultures subjected to dark treatment. The effects of different concentrations of abscisic acid (ABA) on the proliferation and germination of different types of somatic embryos were also evaluated. A concentration of 9.45 μM was found to be the most effective in promoting the proliferation and germination of SE2 embryos. The higher the concentration of ABA (from 0 to 18.90 μM), the higher the percentage of abnormal polycotyledonary embryos produced. The highest percentage of regenerated plants was obtained from SE2 embryos.

Three isomorphic coordination complexes constructed by flexible 1,2,4-triazole-1-acetate with the assistance of halogen or pseudohalogen anions, and [Mn( L )Cl] n ( 1 ), [Co( L )(N 3 )] n ( 2 ) and [Ni( L )(N 3 )] n ( 3 ) ( L = 1,2,4-triazole-1-acetate) have been synthesized and structurally characterized. It is interesting that the linkages of the halogen anions in 1 are the same as those of the pseudohalogen anions in 2 and 3 . Single crystal structure analysis indicated a novel 4,6-connected binodal net with Schlafli {3;4 2 ;5 3 }{3 2 ;4 3 ;5 5 ;6 3 ;7 2 } was formed in these complexes. Dominating antiferromagnetic interactions between the metal ions were detected in these complexes, furthermore evident spin canting presented in 1 and 3 for Dzyaloshinski–Moriya (D–M) interactions.

Different ways of anions introduction were applied to construct cluster-based frameworks, owning to the versatile coordination ability of the formate anion and its sensitivity to the pH value of the reaction system. Three tetra-, penta-, and hexanuclear cluster-based cobalt-organic frameworks, [Co2(L)3(HCO2)·MeOH]n (1), [Co5(L)6(OH)2(NO3)2·2H2O]n (2), and [CoL(HCO2)]n (3) [L = (E)-3-(pyridin-3-yl)acrylate], have been successfully synthesized. In these complexes, each CoII cluster is linked by twelve L ligands with different connectivities to generate unique topological nets. In 1, two formate anions link four CoII ions forming a tetranuclear cluster, and each of the tetranuclear clusters is connected to eight neighbors by L ligands, giving an 8-connected 36418536 net. In 2, the pentanuclear cluster is formed by five CoII ions linked through two OH– and six carboxylate groups, which are further connected by L ligands to afford a pcu (primitive cubic lattice) net. Different from 1 and 2, complex 3 is a 2-fo...

The assembly of CuII, MII (CoII or NiII), azido, and isonicotinate acid N-oxide under hydrothermal conditions straightforwardly gives two isomorphic heterometallic 3d–3d azido complexes formulated [Cu2M(N3)4(INO)2(H2O)4]∞ (INO = isonicotinate N-oxide; M = Co for 1 and Ni for 2). In the structure of the complexes, CuII ions have a trigonal-bipyramidal-coordinated configuration, whereas the MII ions have octahedral geometry with two water molecules in the apical positions. The structure of the complexes is based on azido-carboxylate mixed-coordination Cu–M–Cu trimers, which are further linked by double end-on (EO) azido anions through the CuII ions to form a chain structure, and the 1D structure can be described as EO azido/syn–syn carboxylates and double EO azido mixed-bridge spin-sequence chains with –1/2–J1–3/2–J1–1/2–J2–1/2– for 1 and –1/2–J1–1–J1–1/2–J2–1/2– for 2. Magnetic studies indicated that 1 and 2 are both metamagnets for the weak antiferromagnetic interactions between the ferromagnetic chains.

Three new CoII–azido complexes, [Co3(L)2(o-BDC)2(N3)2]n (1), [Co3(L)2(m-BDC)2(N3)2]n·nH2O (2), and [Co2(L)2(p-BDC)(N3)2]n·2nMeOH (3) [o-BDC = 1,2-benzenedicarboxylate, m-BDC = 1,3-benzenedicarboxylate, p-BDC = 1,4-benzenedicarboxylate, and L = di(1H-imidazol-1-yl)methane], have been constructed from di(1H-imidazol-1-yl)methane, azido, and different aromatic dicarboxylates under hydrothermal conditions. Complex 1 takes a dia topology with the Co3 units as connecting nodes, and complex 2 is a two-dimensional sql layer that further extends to a three-dimensional (3D) supramolecular network via π···π interaction between m-BDC ligands, while complex 3 forms a 3D pcu network based on Co2 units as nodes. The investigaton of magnetic properties of complexes 1–3 demonstrates that they all display ferromagnetic coupling between CoII ions but antiferromagnetic interaction between Co3 or Co2 units.

Using two structurally related benzoates bearing different H-bond acceptors as co-ligands, three new azido-CuII compounds, [Cu(L1)(N3)(H2O)]n (1), [Cu(L1)(N3)(MeOH)]n (2), and [CuL2HL2(N3)3(H2O)]n (3) (HL1 = 4-nitrobenzoic acid; HL2 = 2-phenyl-4-quinolinecarboxylic acid), have been synthesized and structurally characterized. 1 is a carboxylate/EO-azido bridged copper chain, forming 3D structure by H-bonds, and 2 has a similar chain structure as 1 but forming a 2D structure by H-bonds, while 3 is a 3D supramolecular network with ternary center H-bonds. Magnetic study indicates that domain ferromagnetic coupling interactions were found to exist in complexes 1 and 3.

Four new coordination complexes with azole heterocycle ligands bearing acetic acid groups, [Co(L1)2]n (1), [CuL1N3]n (2), [Cu(L2)2·0.5C2H5OH·H2O]n (3) and [Co(L2)2]n (4) (here, HL1=1H-imidazole-1-yl-acetic acid, HL2=1H-benzimidazole-1-yl-acetic acid) have been synthesized and structurally characterized. Single-crystal structure analysis shows that 3 and 4 are 2D complexes with 44-sql topologies, while another 2D complex 1 has a (43)2(46)-kgd topology. And 2 is a 3D complex composed dinuclear μ1,1-bridging azido CuII entities with distorted rutile topology. The magnetic properties of 1 and 2 have been studied.

This paper reports two new coordination polymers formed by carboxylate-substituted benzoimidazole and formate ligands: [Mn(L)·(HCO2)] n (1) and [Co(L)·(HCO2)] n (2) (L = benzoimidazol-1-yl-acetate). Complexes 1 and 2 are isomorphous and adopt a new 3,6-connected three-nodal topology showing interesting magnetic properties: spin canted antiferromagnetism for MnII complex 1, but simple antiferromagnetic coupling for CoII complex 2.

The investigation of magnetic materials with fascinating structures and unusual magnetic behavior has witnessed flourishing development. Transition-metal hydroxides are of particular significance because of their potential application in magnetic devices (as substitutes for traditional ferrite or nanometric magnetic memory units), and have been extensively explored. Even so, it is still a tremendous challenge for researchers to rationally design, precisely control, artfully modulate, and effectively re-assemble new transition-metal/hydroxide species (hydroxide-bridged clusters, chains, and layers). In the hydroxyl inorganic layers (such as Cu(OH)2, FeO(OH), Mg(OH)2, etc.), the hydroxide groups are present in m2 and m3 modes. To replace some of the hydroxide ligands with other bridging groups in order to alter the magnetic properties is still a challenge to chemists today. As we know, azide is one of the most studied ligands in magnetochemistry, and its complexes display exciting magnetic properties ranging from long-range ordering to SMM (single-molecule magnet) and SCM (single-chain magnet) behavior. Additionally, the magnetic interaction through an azide bridge can be easily predicted based on its bridging mode and the M-N-M angles. The most typical bridging modes are end-to-end (EE, m2-1,3) and end-on (EO, m2-1,1), usually resulting in antiferromagnetic and ferromagnetic coupling, respectively, but this greatly depends on the Cu-N-Cu angle for end-on azides. Azides can also bridge more than two ions in their EO mode; for instance, it can bridge three metal ions in a pyramidal fashion analogous to that of a m3-OH group. In view of azides being able to take both m2-1,1 and m3-1,1,1 bridging modes, it may replace some OH positions in the 2D inorganic layer, which could lead to different magnetic behavior. To avoid the inorganic layer collapsing or aggregating into a 3D solid, a second ligand is usually introduced into the system. Herein, phthalic acid (H2-pta) is our second ligand of choice. A Cu / N3 /OH /pta network could have a high negative charge and counterion will then be needed. Herein we report the synthesis of an unusual 2D N3-Cu -OH complex, [CuACHTUNGTRENNUNG(H2O)6]ACHTUNGTRENNUNG[{Cu2(N3)4/3-(OH) ACHTUNGTRENNUNG(pta)}6] (1). Indeed, our results show that the [Cu ACHTUNGTRENNUNG(H2O)6] 2+ complex ion from the CuACHTUNGTRENNUNG(NO3)2 aqueous solution may serve as a template for the [Cu24] macrocycles. The crystal structure of complex 1 (Figure 1) consists of a new anionic 2D layer network containing two Cu ions, one phthalic anion (in m4-O,O’,O’’,O’’’ bridging mode), one m3 hydroxyl anion, and =3 azide anions, which take m2-1,1 and m3-1,1,1 bridging modes (Figure S1). As can be seen in Figure 1 (top), Cu1 is five-coordinate with a distorted square-based pyramid CuN2O3 geometry formed by the coordination of two nitrogen atoms, from the m2-1,1and m31,1,1-azide anions (apical position) (Cu1 N1=2.000(5), Cu1 N4=2.287(3) ;), and three oxygen atoms, one from the m3 hydroxyl anion and two from phthalic anions (Cu1 O5=1.969(4), Cu1 O1=1.983(4), Cu1 O4=2.018(4) ;). The square-based pyramidal coordination sphere of Cu2 is CuNO4, in which the N atom is from a m2-1,1 azide anion (Cu2 N1A=1.972(5) ;), and the four oxygen atoms are from two m3 hydroxyl anions and two phthalic anions (one occupied the apical position) (Cu2 O5=1.954(4), Cu2 O5A=1.979(4), Cu2 O2=2.646, Cu2 O3=1.934(4) ;). Two hydroxyl anions in the m3 mode (Cu1-O5-Cu2=100.74, Cu1-O5-Cu2A=118.24, Cu2-O5-Cu2A=100.308) bridge [a] Y.-F. Zeng, X. Hu, J.-P. Zhao, B.-W. Hu, Dr. F.-C. Liu, Prof. X.-H. Bu Department of Chemistry Nankai University Tianjin 300071 (China) Fax: (+86)22-2350-2458 E-mail : buxh@nankai.edu.cn [b] Dr. E. C. SaCudo Departament de QuJmica InorgKnica Universitat de Barcelona Diagonal, 647, Barcelona (Spain) Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/chem.200800068.

The X-ray crystal structures, magnetic susceptibilities from 2 to 300 K, and theoretical analyses of the magnetism for 1D and trinuclear azido Cu(II) carboxylate complexes [Cu(1.5)(hnta)(N(3))(2)(H(2)O)](n) (1) and [Cu(3)(hnta)(4)(N(3))(2)(H(2)O)(3)] (2), respectively, where hnta is 6-hydroxynicotinate, are described. Although both exhibit strong ferromagnetic coupling, discrete complex 2 exhibits long-range ferromagnetic ordering, while the very similar 1D system 1 does not. Density functional calculations provided accurate J values and allowed rationalization of the ferromagnetic coupling in terms of the magnetic orbitals and spin densities.

A new 3-D mixed valence copper-azido coordination polymer, [Cu I · Cu II (N 3 )(pzc) 2 (H 2 O)] n 1 , has been synthesized and characterized, and its magnetic properties studied. In this compound, the azide acts as rare asymmetric μ 1,1,3 bridging mode. The azide ligands and the Cu(2) ions act as 3-connecting nodes, and the Cu(1) ions act as 4-connecting nodes. The overall net takes rare topology with the Schlafli symbol of (6.8 2 )(6.8 2 )(6.8 5 ).

A new azido-NiII complex constructed from nicotinate has been obtained by cation−anion pairs as templates under hydrothermal conditions, which exhibits three-dimensional Kagome topology and ferromagnetic coupling.

A new 3D Mn(II) coordination polymer, [Mn(2)(HCO(2))(L)(2)(N(3)) x MeOH](infinity) (1) (L = nicotinate N-oxide), was synthesized by a solvothermal reaction and characterized magnetically. Complex 1 is a typical antiferromagnet with alternating azide/azide/formate/formate bridges, exhibiting a new -J(1)J(1)J(2)J(2)- coupling sequence. This is the first complex to contain an azide, formate and another type of carboxylate ligand.

Two new 3D copper(II) azido isomers, [Cu(N3)(nic)]infinity (1 and 2) (nic = nicotinate), have been synthesized and characterized. To the best of our knowledge, 1 is the first metal azido complex showing rutile-type topology, while 2 is a chiral compound obtained by spontaneous resolution upon crystallization.

Two M(II) tetranuclear complexes bridged only by azido, Mn4(N3)(7.3)Cl(0.7)L4 (1) and Co4(N3)8L4 (2) in which the four M(II) ions are precisely coplanar bridged only by six azido anions, were obtained by using 4,5-diazafluoren-9-one (L) as a corner ligand. Magnetic studies indicate that ferromagnetic coupling was conducted by the azido anions between M(II) ions. At low temperature, 1 exhibits a large magnetocaloric effect and 2 shows field-induced multiple magnetic relaxations.

A magnetic isolated chain-based substituted cobalt-formate framework was obtained with isonicotine as a spacer. In the chain, canted antiferromagnetic interactions exist in between the Co(II) ions, and slow magnetic relaxation is detected at low temperature. For the block effects of the isonicotine ligands, the complex could be considered as a peculiar example of a weak ferromagnetic single-chain-magnet.

We describe a new application of megaprimer polymerase chain reaction (PCR) for constructing a tandemly repeated DNA sequence using the drought responsive element (DRE) from Arabidopsis thaliana as an example. The key feature in the procedure was PCR primers with partial complementarity but differing melting temperatures (T(m)). The reverse primer had a higher T(m), a 3' end complementary to the DRE sequence and a 5' region complementary to the forward primer. The initial cycles of the PCR were conducted at a lower primer annealing temperature to generate products that served as megaprimers in the later cycles conducted at a higher temperature to prevent annealing of the forward primer. The region of overlap between the megaprimers was extended for generating products with a variable copy number (one to four copies) of tandem DRE sequence repeats (71 bp). The PCR product with four tandem repeats (4× DRE) was used as a template to generate tandem repeats with higher copies (copy number large than four) or demonstrated to bind DRE-binding protein in an yeast one-hybrid assay using promotorless reporter genes (HIS and lacZ). This PCR protocol has numerous applications for generating DNA fragments of repeated sequences.

Five new isomorphic three-dimensional (3D) heterometallic 3d-3d azide complexes, [CuNi(1-x)Co(x)(N(3))(2)(isonic)(2)](∞) (x = 0 for 1, x = 0.3 for 2, x = 0.5 for 3, x = 0.6 for 4, and x = 1 for 5), were obtained by assembling Cu(II), M(II) (Ni(II) and Co(II)), azide, and pyridyl carboxylate in hydrothermal condition. The 3D structure can be described as end on (EO) azide and syn,syn carboxylates mixed bridged alternate Cu-M chains linked by the pyridyl groups. Dominant ferromagnetic interactions were observed between the Cu(II) and M(II) ions in the chains. At low temperature diverse magnetic phenomena were presented in those complexes. As the Ni(II) ions were replaced by Co(II) ions with large anisotropy, the magnetism of the complexes change gradually from metamagnet to single-chain magnet (SCM)-like behaviors.

Two new azido-Co(II) complexes with pyrazine carboxylato ligands, [Co(N(3))(L)·H(2)O](n) (L = pyrazine-2-carboxylato) (1) and [CoNa(N(3))(2)(L)](n) (2), have been obtained by carefully tuning the Co(II):N(3)(-) ratio. Here we present the structural and magnetic characterization of these new species. Modulation of the coordination environment of Co(II) leads to a variation of the magnetic properties of the obtained compounds. Complex 1 exhibits ferromagnetically coupled [Co(2)] units that form the rungs of the ladder with a nearly negligible coupling between these units, while complex 2 is a 2D arrangement of 1D Co(II) single-chain magnets.

By changing template cation but introducing trivalent iron ions in the known niccolite structural metal formate frameworks, three complexes formulated [NH(2)(CH(3))(2)][Fe(III)M(II)(HCOO)(6)] (M = Fe for 1, Mn for 2, and Co for 3) were synthesized and magnetically characterized. The variation in the compositions of the complexes leads to three different complexes: mixed-valent complex 1, heterometallic but with the same spin state complex 2, and heterometallic heterospin complex 3. The magnetic behaviors are closely related to the divalent metal ions used. Complex 1 exhibits negative magnetization assigned as Neel N-Type ferrimagnet, with an asymmetric magnetization reversal in the hysteresis loop, and complex 2 is an antiferromagnet with small spin canting (α(canting) ≈ 0.06° and T(canting) = 35 K), while complex 3 is a ferrimagnet with T(N) = 32 K.

The hydrothermal reaction of Ni(NO(3))(2).6H(2)O, NaN(3) phenanthroline and nicotinic acid yielded a one-dimensional (1D) complex, [Ni(1.5)(N(3))(2)(phen)(nic)](n) (1) (phen = phenanthroline, nic = nicotinate), which is a new example of the named orbital countercomplementarity-like complex. In 1, the nicotinate shows mu(3)-nic-N,O,O coordination mode, and the azide groups adopt mu(1,1) bridging mode linking Ni(II) ions to form a rare trinuclear Ni(II) unit bridged by a double mu(1,1) azido.

A new three-dimensional Mn(II) complex, [Mn(3)(HCO(2))(2)(L)(2)(OCH(3))(2)], 1 (L = nicotinate N-oxide), was synthesized by solvothermal reaction and magnetically characterized. Complex 1 exhibits an unprecedented 3,6-connected 5-nodal net topology with Schlafli notation {4(2);6}4{4(3)}2{4(6);6(6);8(3);10}2{4(8);6(6);8} and was assigned as a homospin ferrimagnet. Interestingly, when 1 was placed in air for ca. one month, the methoxy anions in 1 were gradually exchanged by hydroxyl anions and 1 underwent a single-crystal-to-single-crystal structural transition to a new but similar complex, [Mn(3)(HCO(2))(2)(L)(2)(OH)(2)] x 4 H(2)O, 2. The anion exchange and water molecules filling the channels of 2 affect the magnetic behavior at low temperature compared to that of 1.

Through the use of a series of structurally related benzoates bearing different substituents as coligands, three new azido-copper compounds, [Cu(benzoate)(N(3))](n) (1), [Cu(2-methyl-benzoate)(N(3))](n) (2), and [Cu(1-naphthoate)(N(3))](n) (3), have been successfully obtained and structurally and magnetically characterized. Single-crystal structure analyses indicated that the uncoordinating substituents in the benzoates greatly affect the structure of the complexes. Complex 1 displays isolated ferromagnetic chains with the largest Cu-N-Cu angle in known carboxylate/end-on-azido mixed-bridged copper systems, while complexes 2 and 3 were 2D coordination polymers, containing mu-(1,1,3,3) and mu-(1,1,3) bridging azides and exhibiting new azido-copper networks with (4(4)) and (4.8(2)) topologies, respectively. Furthermore, 2 was a chiral complex obtained through spontaneous resolution. In the low-temperature range, both 2 and 3 showed spontaneous magnetization with characteristics of soft ferromagnetic magnetism with phase transition temperatures of 13 and 10 K, respectively.

The investigation of magnetic materials with fascinating structures and unusual magnetic behavior has witnessed flourishing development. Transition-metal hydroxides are of particular significance because of their potential application in magnetic devices (as substitutes for traditional ferrite or nanometric magnetic memory units), and have been extensively explored. Even so, it is still a tremendous challenge for researchers to rationally design, precisely control, artfully modulate, and effectively re-assemble new transition-metal/hydroxide species (hydroxide-bridged clusters, chains, and layers). In the hydroxyl inorganic layers (such as Cu(OH)2, FeO(OH), Mg(OH)2, etc.), the hydroxide groups are present in m2 and m3 modes. To replace some of the hydroxide ligands with other bridging groups in order to alter the magnetic properties is still a challenge to chemists today. As we know, azide is one of the most studied ligands in magnetochemistry, and its complexes display exciting magnetic properties ranging from long-range ordering to SMM (single-molecule magnet) and SCM (single-chain magnet) behavior. Additionally, the magnetic interaction through an azide bridge can be easily predicted based on its bridging mode and the M-N-M angles. The most typical bridging modes are end-to-end (EE, m2-1,3) and end-on (EO, m2-1,1), usually resulting in antiferromagnetic and ferromagnetic coupling, respectively, but this greatly depends on the Cu-N-Cu angle for end-on azides. Azides can also bridge more than two ions in their EO mode; for instance, it can bridge three metal ions in a pyramidal fashion analogous to that of a m3-OH group. In view of azides being able to take both m2-1,1 and m3-1,1,1 bridging modes, it may replace some OH positions in the 2D inorganic layer, which could lead to different magnetic behavior. To avoid the inorganic layer collapsing or aggregating into a 3D solid, a second ligand is usually introduced into the system. Herein, phthalic acid (H2-pta) is our second ligand of choice. A Cu / N3 /OH /pta network could have a high negative charge and counterion will then be needed. Herein we report the synthesis of an unusual 2D N3-Cu -OH complex, [CuACHTUNGTRENNUNG(H2O)6]ACHTUNGTRENNUNG[{Cu2(N3)4/3-(OH) ACHTUNGTRENNUNG(pta)}6] (1). Indeed, our results show that the [Cu ACHTUNGTRENNUNG(H2O)6] 2+ complex ion from the CuACHTUNGTRENNUNG(NO3)2 aqueous solution may serve as a template for the [Cu24] macrocycles. The crystal structure of complex 1 (Figure 1) consists of a new anionic 2D layer network containing two Cu ions, one phthalic anion (in m4-O,O’,O’’,O’’’ bridging mode), one m3 hydroxyl anion, and =3 azide anions, which take m2-1,1 and m3-1,1,1 bridging modes (Figure S1). As can be seen in Figure 1 (top), Cu1 is five-coordinate with a distorted square-based pyramid CuN2O3 geometry formed by the coordination of two nitrogen atoms, from the m2-1,1and m31,1,1-azide anions (apical position) (Cu1 N1=2.000(5), Cu1 N4=2.287(3) ;), and three oxygen atoms, one from the m3 hydroxyl anion and two from phthalic anions (Cu1 O5=1.969(4), Cu1 O1=1.983(4), Cu1 O4=2.018(4) ;). The square-based pyramidal coordination sphere of Cu2 is CuNO4, in which the N atom is from a m2-1,1 azide anion (Cu2 N1A=1.972(5) ;), and the four oxygen atoms are from two m3 hydroxyl anions and two phthalic anions (one occupied the apical position) (Cu2 O5=1.954(4), Cu2 O5A=1.979(4), Cu2 O2=2.646, Cu2 O3=1.934(4) ;). Two hydroxyl anions in the m3 mode (Cu1-O5-Cu2=100.74, Cu1-O5-Cu2A=118.24, Cu2-O5-Cu2A=100.308) bridge [a] Y.-F. Zeng, X. Hu, J.-P. Zhao, B.-W. Hu, Dr. F.-C. Liu, Prof. X.-H. Bu Department of Chemistry Nankai University Tianjin 300071 (China) Fax: (+86)22-2350-2458 E-mail : buxh@nankai.edu.cn [b] Dr. E. C. SaCudo Departament de QuJmica InorgKnica Universitat de Barcelona Diagonal, 647, Barcelona (Spain) Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/chem.200800068.

A novel one-dimensional manganese(II) azido complex, [Mn2(N3)4(phen)2]n (1), in which the azido bridging ligands take on an unusual new type of combination with the metal center as the sign of [−EO−EO−EO−EE−]n, has been hydrothermally synthesized, and its magnetic properties have been studied.

The molecular 1:1 complexation of cinchona alkaloids by mono(6-deoxy-6-{[(R)-1-(hydroxymethyl)propyl]amino})-beta-cyclodextrin (1) in aqueous solution has been investigated by 2D-NMR, fluorescence titration, and fluorescence-lifetime experiments. Generally, with 1 as the host, in contrast to beta-cyclodextrin proper, strong binding of quinine (2; Ka = 84,200 M(-1)) and quinidine (3; Ka = 27,300 M(-1)) at pH 6.8 was observed, as monitored by an increase in fluorescence intensity, with a fair degree of diastereoisomer discrimination (ca. 3:1). To rationalize these results, two possible cooperative complexation modes, including specific H-bonding interactions to the chiral tether of the cyclodextrin portion, are proposed.

A new chiral 3D heterometallic coordination polymer [NaCo2(L)2(N3)·(MeOH)]∞ (1) (L = 2,6-pyridinedicarboxylate) was synthesized and characterized magnetically. Ferro- and antiferromagnetic interactions co-exist in 1, which results in a magnetic phase transition at the high temperature of 29 K.

The Cu(II) ions usually have different coordinated geometry to other 3d ions, especially Ni(II) and Co(II) ions, in azido-carboxylate mixed ligand systems. That provides a potential way to synthesize rare heterometallic 3d-3d azido complexes with peculiar magnetic properties. Assembling Cu(II), M(II) (M = Ni and Co), azido and nicotinic acid in hydrothermal condition, two novel isomorphic 3D heterometallic 3d-3d azido complexes, [CuM(N(3))(2)(nicotinate)(2)](∞) (M = Ni(II) for 1 and Co(II) for 2) were obtained. The structure of the complexes can be described as EO azido and syn,syn carboxylate mixed bridged spin sequence chains (-1/2-J(1)-1-J(2)-1/2- for 1 and -1/2-J(1)-3/2-J(2)-1/2- for 2) linked by the pyridyl groups. Dominant ferromagnetic interactions were observed between the Cu(II) and M(II) ions in the chains despite the largest M-N-M angle of about 129° in the 3d metal azido-carboxylate mixed coordinated systems and weak antiferromagnetic interactions between the chains. At low temperature, a spin-flop phase transition was present in the Co(II) involved complex 2.

Three new 1D lanthanide-azido complexes, [Ln(2)(N(3))(isonic)(2)-(OH)(3)(Hisonic)(H(2)O)](n) (Ln = Gd(III), Eu(III) and Sm(III)), were synthesized by hydrothermal reaction and their magnetic properties were studied.

A new 3D porous Ni(II)-azido complex has been synthesized and characterized and exhibits guest sorption properties explored by single-crystal to single-crystal transformations and linear ferromagnetic chains held together by a Ni-isonicotinate framework.

Four novel AgI coordination complexes with azole heterocycle ligands bearing acetic acid group, [AgL1]n (1), [Ag(L2HL2)]n (2), [AgL3]n (3) and [Ag(L4)]n (4) (here, HL1 = 1H-imidazole-1-acetic acid, HL2 =1H-benzimidazole-1-acetic acid, HL3 =1H-1,2,4-triazole-1-acetic acid, HL4 =1H-benzotriazole-1-acetic acid), have been synthesized and structurally characterized by elemental analysis, IR and X-ray diffraction. Structural analyses show that complex 1 possesses a two-dimensional structure, which contains silver chains formed by weak Ag–Ag interactions, and 2 consists of neutral chains connected by weak bonds (O⋯H⋯O), while 3 and 4 have a three-dimensional network and a one-dimensional chain structure, respectively. It is interesting that in 1 there exist Ag–Ag interactions with a separation of 3.156 A, which play an important role in the formation of the complex. Furthermore, the conductivity of 1 was studied in the powder state.

The reaction of LnIII salts with 1,5-naphthalenedisulfonate (1,5-NDS) or 2,7-naphthalenedisulfonate (2,7-NDS), and phenanthroline (phen) under hydrothermal conditions gave a series of new 2-D complexes {[Ln(1,5-NDS)1.5(phen)2(H2O)2]·3H2O}n [Ln = EuIII (1), GdIII (2), NdIII (3), TbIII (4)] and dinuclear compounds [Ln2(2,7-NDS)2(μ2-OH)2(phen)4(H2O)2]·4H2O [Ln = EuIII (5), GdIII (6), TbIII (7)], respectively. 1–4 are puckered (6,3) networks with 1,5-NDS as a bridge and phen chelating to LnIII ions. 5–7 are hydroxyl bridged dinuclear entities, which extend to 2-D networks by H-bonds.