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By introduction of 2,2′-bipy or 1,10-phen as a second organic ligand, four new zinc(ii) diphosphonate hybrids with mixed ligands, namely, [Zn(2,2′-bipy)(hedpH2)]·0.5H2O (1), [Zn(1,10-phen)(hedpH2)]·H2O (2), [Zn2(1,10-phen)(hedpH2)2]·H2O (3) and [Zn(1,10-phen)(hedpH2)] (4) (hedpH4= 1-hydroxyethylidenediphosphonate, 2,2′-bipy = 2,2′-bipyridine, 1,10-phen = 1,10-phenanthroline) have been synthesized under hydrothermal conditions. Compounds 1and 2adopt a two-dimensional supramolecular network structure containing {[Zn(2,2′-bipy)(hedpH2)]2} or {[Zn(1,10-phen)(hedpH2)]2} units. The neighboring units interdigitate through hydrogen bonding interactions to give a 2D supramolecular network. Compounds 3and 4also have a two-dimensional supramolecular network structure. In compounds 3and 4, 1D Zn–diphosphonate chains were formed. These 1D chains are further connected to adjacent chains through hydrogen bonds to form a 2D supramolecular network. A notable feature for compound 4is the presence of the alternate left- and right-handed helical chains in the structure. The luminescence properties of compounds 1–4have also been studied. [ABSTRACT FROM AUTHOR]

Reaction of the Ir(iii) dimer [(η5-C5Me5)IrCl2]2with PMeXyl2(Xyl = 2,6-C6H3Me2), in the presence of the poorly coordinating base 2,2,6,6-tetramethyl piperidine, gives a chloride complex 1-Cl, resulting from hydrogen chloride elimination involving one of the phosphine benzylic hydrogen atoms and concomitant cyclometallation. Related compounds containing other halide or pseudohalide ligands, 1-Br, 1-Cl, 1-SCN, can be made, the latter featuring S-coordination of the ambidentate thiocyanate to the soft Ir(iii) Lewis acid centre, as suggested by IR data and demonstrated by X-ray crystallography. Hydride 2-H, and alkyl derivatives 3(Me) and 4(CH2SiMe3) can also be prepared from 1-Cland appropriate hydride and alkylating reagents. An interesting H/D exchange chemistry that occurs in the presence of CD3OD has been disclosed for 1-Cl, 1-Brand 2-H. For the halide derivatives, deuterium incorporation takes place into the methylene and methyl sites of their cyclometallated ligand, whereas for 2-Honly the hydride and methylene (Ir–CH2) protons participate in the exchange, which is strikingly accelerated by catalytic amounts of acids. [ABSTRACT FROM AUTHOR]

The reaction of bis(ferrocenyl)methylsilane 1with two carbosilane dendritic cores containing terminal allyl units gives dendrimers functionalized with eight interacting ferrocenyl units. They show two reversible ferrocenyl waves in cyclic voltammetry (CV) and form derivatized Pt electrodes. Platinum electrodes modified with electrodeposited films of these two dendrimers exhibit electrocatalytic activity towards the reduction of oxygen and both oxidation and reduction of hydrogen peroxide. The molecular structure of 1has been determined by single-crystal X-ray diffraction studies. [ABSTRACT FROM AUTHOR]

The synthesis of novel heterobimetallic derivatives of general formula [RuClCp(PPh3)-μ-dmoPTA-1κP:2κ2N,N′-M(acac-κ2O,O′)2] (M = Ni (3), Zn (4); dmoPTA = 3,7-dimethyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane) is described. The preparations of the ruthenium–cobalt analogue (M = Co (2)) and the starting compound [RuClCp(HdmoPTA-κP)(PPh3)](CF3SO3) have been revised and their yield improved. Similar to 2, the solid state structures of 3and 4show that the dmoPTA-P and the dmoPTA-NCH3atoms are involved in the coordination to the {RuCpCl(PPh3)} and {M(acac)2} moieties, respectively. The size of the diffusing units is almost the same for the three binuclear complexes, indicating that they exhibit similar solution structures. The diamagnetic ruthenium–zinc derivative was fully characterized in solution at 193 K by NMR as two diastereomeric pairs of enantiomers (R-Ru, Δ-Zn; R-Ru, Λ-Zn; S-Ru, Δ-Zn; S-Ru, Λ-Zn). Finally, the electrochemical properties of the complexes have been investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Twelve Pt(ii) complexes with cis-PtP2S2pharmacophores (where P2refers to two monodentate or one bidentate phosphane ligand and S2is a dithiolato ligand) were prepared, characterized and evaluated as potential antiproliferative agents. The various compounds were first studied from the structural point of view; afterward, their solubility properties as well as their solution behaviour were analyzed in detail. Antiproliferative properties were specifically evaluated against A2780 human ovarian carcinoma cells, either resistant or sensitive to cisplatin. For comparison purposes similar studies were carried out on four parent cis-dichloro bisphosphane Pt(ii)complexes. On the whole, the cis-PtP2S2compounds displayed significant antiproliferative properties while the cis-PtP2Cl2(cis-dichloro bisphosphane Pt(ii)) compounds revealed quite poor biological performances. To gain further insight into the molecular mechanisms of these bisphosphane Pt(ii) compounds, the reactions of selected complexes against the model protein cytochrome c were investigated by ESI-MS and their adduct formation explored. A relevant reactivity with cyt c was obtained only for cis-PtP2Cl2compounds, whereas cis-PtP2S2compounds turned out to be nearly unreactive. The obtained results are interpreted and discussed in the frame of the current knowledge of anticancer platinum compounds and their structure–activity-relationships. The observation of appreciable antiproliferative effects for the relatively inert cis-PtP2S2compounds strongly suggests that these compounds will undergo specific activation within the cellular environment. [ABSTRACT FROM AUTHOR]

Pseudooctahedral complexes [MCl3(NtBu)L2] (M = Nb, L = py 1, ½ tmeda 3; M = Ta, L = py 2, ½ tmeda 4) have been studied by spectroscopic methods. By a VT 1H NMR experiment a mutual exchange process between the pyaxand pyfreein the complexes 1–2was observed, whereas 13C and 15N NMR studies showed in the complexes 3–4a tmeda ligand with an axial/equatorial coordination mode. The reaction of 2with 3 equiv of Grignard reagent produces the methathesis products [TaR3(NtBu)] (R = CH2CMeCH25, CH2CHCHCH36) in which 2-methylallyl and 2-butenyl groups appear with a η3- and σ-coordination mode, respectively. When, toluene solutions of the compounds 5–6were treated with 2 equiv of 2,6-dimethylphenylisocyanide the imido bisiminoacyl compounds [TaR(NtBu){C(R)NAr-κ1C}2] (Ar = 2,6-Me2C6H3; R = CH2CMeCH27, CH2CHCHCH38) can be isolated, viaan imido iminoacyl intermediate [TaR2(NtBu){C(R)NAr-κ1C}] (Ar = 2,6-Me2C6H3; R = CH2CMeCH29) as we have observed in the treatment of 5with 1 equiv of isocyanide; however, the analogous reaction between 5and COPh2leads to the formation of the trisalkoxo imido compound [Ta(OCPh2R)3(NtBu)] (R = CH2CMeCH210). All new complexes were studied by IR and multinuclear NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Two {Co3+–Zn2+} heterobimetallic coordination networks have been synthesized utilizing Co3+complex as the building blocks. The structural studies reveal 2D sheet-like networks where the Co3+containing building blocks are connected through Zn2+ions. Two different building blocks generate two unique networks as evidenced by the crystallographic studies and other properties. These networks are shown to catalyze Lewis metal ion assisted Strecker reaction in heterogeneous manner. [ABSTRACT FROM AUTHOR]

The ligand [(1,3-phenylene)bis(methylene)]bis(1-ethyl-imidazol-2-ylidene) (2) (abbreviated as EtCNHCCHCNHCwith CH = central aromatic ring, = CH2spacer) has been synthesised, and isolated, by deprotonation of [(1,3-phenylene)bis(methylene)]bis(1-ethyl-imidazolium) dichloride, Et(CHimid.CHCHimid.)Cl2(1) with LiN(SiMe3)2. This new, remarkably stable NHC dicarbene ligand is quantitatively protonated with HBr to form [(1,3-phenylene)bis(methylene)]bis(1-ethyl-imidazolium) dibromide Et(CHimid.CHCHimid.)Br2(3) and reprotonated slowly enough in MeOH to allow observation of the monoprotonated intermediate 4. Dicarbene 2reacts with S8to give the dithione compound [(1,3-phenylene)bis(methylene)]bis(1-ethyl-imidazol-2-thione) Et[(SC)CH(CS)] (6). Reaction of 2with [IrCl(CO)(PPh3)2] and [Ir(μ-Cl)(cod)]2yielded the mononuclear [Ir(CO)(PPh3)2Et(CHimid.CHCNHC)(PF6)](PF6) (8) and [IrCl(cod)Et(CHimid.CHCNHC)](PF6) (10) complexes, respectively, and the dinuclear complexes [{Ir(CO)(PPh3)2}2Et(μ-CNHCCHCNHC)](PF6)2(7) and [{IrCl(cod)}2Et(μ-CNHCCHCNHC)] (9), respectively, in which 2acts as a bridging, non-pincer type ligand. Only one other Ir(i) complex has been reported before containing a CNHCCHCNHCligand. The structures of 6and 9were determined by X-ray diffraction and depict different conformations of the (1,3-phenylene)bis(methylene) (or xylylene) moiety. The mononuclear Ir complex 9reacted smoothly with [Rh(μ-Cl)(cod)]2and Cs2CO3to generate a rare example of a heteronuclear NHC complex, [IrRhCl2(cod)2Et(μ-CNHCCHCNHC)] (11). [ABSTRACT FROM AUTHOR]

The combination of a [1111]metacyclophane blocked in 1,3-alternate conformation and bearing four imidazole units with MX2(M = Co, Cu, Zn and Hg; X = Cl or Br) complexes leads to the formation of a series of analogous neutral metallamacrotricycles. In all cases, the structure of the binuclear complexes has been studied by X-ray diffraction methods on single crystals. [ABSTRACT FROM AUTHOR]

(S,R)-Indan–ambox ligand and its ruthenium(ii) complex have been prepared and successfully applied to asymmetric hydrogenation of prochiral simple ketones. A wide range of unfunctionalized ketones are reduced by Ru(ii)-indan–ambox catalyst with excellent enantioselectivities (up to 97% ee). [ABSTRACT FROM AUTHOR]

Key elements in this communication are a very efficient microwave synthesis of [RuCp(naphthalene)][PF6], the precursor of [RuCp(CH3CN)3][PF6], and a Pd-catalysed asymmetric hydrogenolysis to afford planar chiral ruthenium complexes with high levels of enantioselectivity using a bulky chiral phosphoramidite ligand. [ABSTRACT FROM AUTHOR]

Heteroleptic complexes, formed selectively by using a 1 : 1 combination of a σ-donor and a π-acceptor ligand, are involved in Rh- and Pd-catalysed reactions. [ABSTRACT FROM AUTHOR]

Six novel Cd(II) complexes, Cd(bpmi)2Cl2 (1), [Cd(bpmi)2(NO3)2(H2O)]n (2), [Cd2(bpmi)2Cl2(N3)2(CH3OH)2]n (3), [Cd(bpmi)Cl2]n (4), [Cd(bpmi)(SCN)2]n (5) and [Cd(bpmi)(N3)2]n (6), are synthesized by the reaction of different Cd(II) salts with an asymmetric multidentate ligand 1-(benzotriazole-1-methyl)-2-propylimidazole (bpmi). X-ray single-crystal analyses reveal that these complexes show rich structural chemistry ranging from mononuclear (1), one-dimensional (2 and 3), two-dimensional (4 and 5) to three-dimensional (6) structures. These complexes share common features such as they all contain inorganic SBUs and have a high degree of dependence on the corresponding counter anions. In this paper, the fine regulation of counter anions has been discussed in detail. Furthermore, these complexes have been investigated by solid-state UV-vis spectra, thermogravimetric analyses and fluorescence spectra. [ABSTRACT FROM AUTHOR]

The present paper describes a simple access to chiral N,N-donor ligands based on a dioxolane backbone containing two pyrazoles. These ligands can be considered as nitrogen donor analogues to the well established chiral bidentate DIOP ligands which had found wide applications in enantioselective catalysis. The co-ordination chemistry of these ligands is shown exemplarily for palladium(ii) and rhodium(i) complexes. All compounds were completely characterized by means of NMR and IR spectroscopy and by elemental analysis. A series of X-ray structural investigations completes the characterization. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis, structure, and properties of a series of PNP pincer complexes of osmium OsH3Cl[HN(C2H4PiPr2)2] (1), OsH3[N(C2H4PiPr2)2] (2), OsH4[HN(C2H4PiPr2)2] (3), and OsH2(PMe3)[HN(C2H4PiPr2)2] (4). The tetrahydride 3operates as an efficient catalyst at 0.1 mol% loading for the reactions of amination and dehydrogenative coupling of primary alcohols, producing secondary amines and symmetrical esters, respectively. The catalyst 3is distinguished by outstanding stability, and it can be used in an aqueous environment at temperatures as high as 200 °C. [ABSTRACT FROM AUTHOR]

The paper reports the synthesis and characterisation of a series of flexible di-bidentate bridging ligands in which two 4-methyl-2,2′-bipyridine groups are linked at the 4′-position by polymethylene (bbn), linear polyether (bbOn) or linear alkylamine (bbNn) chains of varying length (n). The enantiomers (ΔΔ/ΛΛ) of the racforms of the ruthenium(ii) dinuclear complexes incorporating these ligands – i.e. [{Ru(phen)2}2(μ-BL)]4+(phen = 1,10-phenanthroline; BL = bbn, bbOnor bbNn) – have been isolated by reaction of Δ- or Λ-[Ru(phen)2(py)2]2+(py = pyridine) with the respective bridging ligands. Mononuclear species - in which only one of the bidentate moieties of the bridging ligand is coordinated – have also been isolated, as well as trinuclear and tetranuclear species involving the bb7bridge. Fluorescence displacement studies of the DNA-binding of the dinuclear complexes containing the bbOnand bbNnbridges generally revealed a lower affinity than their bbnanalogues for an oligonucleotide containing a single bulge site; the mononuclear complexes showed a lower affinity - and the trinuclear and tetranuclear complexes a higher affinity – than the dinuclear species, revealing an interesting interplay of lipophilicity, electrostatics and size in the complex/nucleic acid interaction. Cytotoxicity studies of these complexes against a murine leukaemia cell line revealed that the presence of the polyether or polyamine links in the chain lowered the cytotoxicity compared with their polymethylene analogues, and that the bb7-bridged trinuclear and tetranuclear complexes showed considerably enhanced cytotoxicity compared with the dinuclear Rubb7analogue. [ABSTRACT FROM AUTHOR]

The cyclooctatetraene (COT) ring may act as an effective π-type ligand in metal complexes and very often in such complexes it adopts the planar structure, which in fact is not the most favourable conformation when compared with the free COT molecule. Such planarization is usually considered as an effect of COT ring aromatization due to charge transfer from the metal centre into the COT ligand and reorganization of the π-electron structure from a 4nto 4n+2 Hückel system. In this paper it has been shown that the conformational changes of the COT ring, leading to its planarization and partial bond equalization, in the first order are connected with the complexation efficiency and not with the aromatization of COT itself. Such a conclusion was drawn on the basis of statistical analysis of X-ray data collected in the Crystal Structure Database (47 COT rings were taken into consideration, all found in the selected highest quality X-ray measurements) and advanced quantum-chemical calculations, including analysis of the electron density distribution made in the framework of Atoms-in-Molecules Quantum Theory. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis and characterisation of Ru-based, water-soluble complexes [RuII(X)(Y)(TMC)] (X, Y = H2O or OH; TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane) capable of behaving as colorimetric, water-soluble, dissolved N2sensors. Unlike previous water-soluble N2complexes, binding to N2is both reversible and pH-switchable, i.e., binding can be switched on at high pHs and switched off at low pHs. Sensing can be performed at partial pressures of N2as low as 0.01 MPa. [ABSTRACT FROM AUTHOR]

This paper illustrates the versatility of mono- and heterobinuclear complexes with dissymmetric compartmental ligands in designing molecular and supramolecular heterometallic systems. Mononuclear complexes with side-off bicompartmental ligands derived from o-vanillin act efficiently, through their empty compartment, as hydrogen-bond receptors and as second coordination sphere ligands. These Schiff- bases are also suitable for synthesizing 3d-3d′ and 3d-4f heterobinuclear complexes. Both 3d-3d′ and 3d-4f complexes can be employed as nodes in obtaining coordination polymers with various dimensionalities and network topologies, as well as interesting magnetic and optical properties. [ABSTRACT FROM AUTHOR]

For over 30 years cisplatin has been one of the most active antitumour agents in clinical use, nevertheless research for overcoming cisplatin toxicity and resistance or for improving its efficacy has never ceased. In this context we have recently proposed dinuclear Pt complexes with bridging geminal bisphosphonates as novel Pt-prodrugs with potential activity at the bone surface after embedment in inorganic matrices and implantation at the tumour site. In the present paper we report the synthesis and full characterization of four new platinum complexes having a dinuclear structure with a bisphosphonate (2-ammonium-1-hydroxyethane-1,1-diyl-bisphosphonate or 3-ammonium-1-hydroxypropane-1,1-diyl-bisphosphonate, AHBP-H and PAM-H, respectively) acting as a bridging ligand between two platinum moieties (cis-[Pt(NH3)2]2+, directly related to cisplatin, and [Pt(cis-1,4-DACH)]2+, known to be able to overcome the cisplatin resistance). Moreover, as a preliminary investigation, the in vitrocytotoxicity of the new complexes has been evaluated on a panel of 13 human tumour cell lines including cisplatin- and multidrug-resistant sublines. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis, crystal structures, and magnetic properties of a series of mixed-valence polynuclear manganese complexes bridged by a dianionic 1,2,4-triazole-based ligand L2−(H2L = 3-(2-phenol)-5-(pyridin-2-yl)-1,2,4-triazole). Complexes 1to 3show a similar binuclear structure, with the central core of [MnIIMnIII(L)2] and some other small molecules also coordinated to the two Mn centers. The two [MnIIMnIII(L)2] subunits can be further connected by different dicarboxylic acids to construct non-charged tetranuclear complexes 4to 7. In these complexes, each deprotonated dianionic ligand L2−acts as a μ2-bridged ligand to coordinate two Mn centers viathe 1,2,4-triazole ring. Bond valence sum (BVS) calculations and Mn surrounding bond lengths indicate that the Mn center coordinated to the pyridine N atoms in the +2 oxidation state, while another Mn center coordinated to the phenolic O atoms is in the +3 oxidation state. The MnIIIcentre shows Jahn–Teller elongation along one of the axes. Magnetic studies show the presence of ferromagnetic MnIII–MnIIcoupling in the binuclear (1–3) and tetranuclear (4–7) complexes with the magnetic coupling constant (J) ranging from 0.58 to 1.17 cm−1, based on the Hamiltonian H= −2JS1·S2(S1= 5/2 and S2= 2). In all cases both z′J′ (intermolecular interactions) and Dparameter (Zero Field Splitting of the Mn (III) ion) has been introduced to improve the corresponding fit. The relationship of the coupling interaction between the MnII/MnIIIand their electronic structures is discussed. [ABSTRACT FROM AUTHOR]

This paper reports the first systematical synthesis of near-monodisperse potassium and lithium rare earth (RE) fluoride (K(Li)REF4) nanocrystals with diverse shapes (cubic KLaF4and KCeF4wormlike nanowires, nanocubes and nanopolyhedra; cubic LiREF4(RE = Pr to Gd, Y) nanopolyhedra; tetragonal LiREF4(RE = Tb to Lu, Y) rhombic nanoplates) viaco-thermolysis of Li(CF3COO) or K(CF3COO) and RE(CF3COO)3in a hot oleic acid/oleylamine/1-octadecene solution. The effects of the solvent composition, reaction temperature and time on the crystal phase purity, shape, and size of the as-prepared nanocrystals have been investigated in detail. The formation of monodisperse nanocrystals is found to strongly depend upon the nature of both alkali metals from Li to K, and the rare earth series from La to Lu and Y. Based on the series of experimental results, a controlled-growth mechanism has also been proposed. In addition, the ease of doping of these as-synthesized host nanocrystals for designed luminescence properties is assessed. For example, monodisperse and single-crystalline Eu3+doped KGdF4, Yb3+and Er3+co-doped LiYF4nanocrystals redispersed in cyclohexane exhibit visible room-temperature red and green emissions under ultraviolet (UV) excitation and near infrared (NIR) 980 nm laser excitation, respectively. [ABSTRACT FROM AUTHOR]

In this paper, ten novel silver(I) sulfonates containing pyrazine derivatives, [Ag(L1)(Pyr)(H2O)] (1), [Ag(L1)(2,3-Pyr)] (2), [Ag(L1)(2,5-Pyr)]·H2O (3), [Ag(L1)(2,3,5-Pyr)] (4), [Ag(L1)(2,3,5,6-Pyr)] (5), [Ag(L2)(Pyr)] (6), [Ag(L2)(2,3-Pyr)] (7), [Ag(L2)(2,6-Pyr)] (8), [Ag(L2)(2-Pyr)] (9), and [Ag(L2)(2,5-Pyr)]·H2O (10) (L1 = 3-amino-4-methylbenzenesulfonate anion; L2 = 2-amino-3,5-dimethylbenzenesulfonate anion; Pyr = pyrazine; 2-Pyr = 2-methylpyrazine; 2,3-Pyr = 2,3-dimethylpyrazine; 2,6-Pyr = 2,6-dimethylpyrazine; 2,5-Pyr = 2,5-dimethylpyrazine; 2,3,5-Pyr = 2,3,5-trimethylpyrazine; 2,3,5,6-Pyr = 2,3,5,6-tetramethylpyrazine), have been synthesized and characterized by elemental analyses, IR spectroscopy and X-ray crystallography. In 1and 7, the silver(I) centers are linked by bridging pyrazine ligands to form one-dimensional (1D) chains. The silver(I) ions of the compounds 2–6are bridged by pyrazine ligands and sulfonate anions to form 2D polymeric structures. Compounds 8–10show 3D structures with diamond topologies. These results indicate that the steric hindrance of the pyrazine derivatives and the sulfonate anions containing different substituting groups play important roles in the framework formation of the silver(I) polymers. In addition, the luminescent properties of these compounds are also discussed in detail. [ABSTRACT FROM AUTHOR]

The paper reports on the synthesis, crystal structure, differential scanning calorimetry (DSC) and magnetic properties of a spin crossover salt of formula [Fe(bpp)2](cis,cis-1,3,5-Hchtc)·5.5 H2O (1) (bpp = 2,6-bis(pyrazol-3yl)pyridine; cis,cis-1,3,5-Hchtc = monoprotonated cyclohexanetricarboxylate dianion). The salt shows a porous structure with water molecules sitting in the channels. The electronic configuration of the Fe2+ions is high-spin (HS). Desolvation of 1yields a material exhibiting an abrupt spin crossover with a thermal hysteresis loop located near room temperature (T1/2↑ = 319 K and T1/2↓ = 309 K). Rehydration of this desolvated salt yields an essentially low-spin (LS) material. This is the first example of a series of hydrogen-bonded porous structures that combine a Fe(bpp)2spin crossover unit acting as a hydrogen-bond donor and polycarboxylate anions acting as hydrogen-bond acceptors with different connectivities. [ABSTRACT FROM AUTHOR]

Syntheses and crystal structures of four new hydrazone-based Cu(ii) complexes, [{Cu(L1)(H2O)}2(μ-pyraz)](ClO4)2(1), [{Cu(L1)(OClO3)}2(μ-4,4′-bipy)] (2), [{Cu(L2H)}(μ-pyraz){Cu(L2H)(OClO3)}].(ClO4) (3) and [{Cu(L2)}2(μ-bpe)] (4) [L1H = condensation product of benzhydrazide and pyridine-2-carbaldehyde and L2H2= condensation product of benzoyl acetone and benzhydrazide], bridged by various organic spacers [pyrazine (pyraz), 4,4′-bipyridine (4,4′-bipy) and 1,2-di(4-pyridyl)ethane (bpe)] are reported in this paper. The single-crystal X-ray crystallographic studies reveal that all are dinuclear units where 1and 3form strong intermolecular H-bonding to form sheets of interconnected ions, whereas 2forms sheets of dinuclear chains through π–π interactions; in 4, molecules are linked only through van der Waals interactions. The variable-temperature magnetic moment studies reveal that 1and 3show antiferromagnetic coupling between the Cu(ii) centers at lower temperatures. The binding ability of 1with calf thymus DNA [CT-DNA] is reported using various spectroscopic studies (UV-Vis titration, circular dichroism and fluorescence). The binding constants of 1with CT-DNA, as calculated by different methodologies, are of the order of 105M−1. The mode of interaction between 1and CT-DNA has been predicted using circular dichroic (CD) spectroscopy, where it has been shown that 1most probably interacts with DNA viaintercalation between the base pairs leading to a change in B-DNA conformation. 1is also able to cleave supercoiled (SC) plasmid DNA pUC19 in a time and dose dependent manner as demonstrated by agarose gel electrophoresis, and also demonstrates its potential to cleave the SC plasmid DNA viaboth oxidative and hydrolytic mechanisms. Approximately 50% of leukemic cells are found to be dead when two representative leukemic cell lines are exposed to 1(∼80 μM) even for 24 h as determined by different cell cytotoxicity assays. Preliminary results also showed that, at 20 μM, 1could selectively induce apoptosis in leukemic cells without affecting normal lymphocytes. [ABSTRACT FROM AUTHOR]

In this paper, flowerlike Co11(HPO3)8(OH)6superstructures were selectively synthesized viaa facile hydrothermal route on a large scale in the presence of a certain amount of Ni2+ions, employing CoCl2·6H2O and NaH2PO2·H2O as the reactants, NaHCO3as the pH adjustor. HPO3−ions were provided based on the dismutation of H2PO2−ions in a weak basic solution. The reaction was carried out at 170 °C for 10 h. The as-obtained products were characterized by X-ray powder diffraction (XRD), energy dispersive spectrometry (EDS), field emission scanning electron microscopy (SEM), selected area electron diffraction (SAED) and high resolution transmission electron microscopy (HRTEM). Research showed that the Ni2+ions in the system played a crucial role in the formation of flowerlike Co11(HPO3)8(OH)6superstructures. Some factors influencing the morphology of Co11(HPO3)8(OH)6, including the reaction time, temperature, and the kinds of metal ions were investigated. A possible growth mechanism was proposed. [ABSTRACT FROM AUTHOR]

Seven isomorphous 1D chain Ln3+complexes Ln(BTA)(HCOO)(H2O)3(Ln = Pr (1), Gd (2), Eu (3), Tb (4) Dy (5), Er (6) and Yb (7)), and two formate coordinating and bridging 3D Ln3+complexes Ln(HCOO)3(Ln = Pr (8) and Nd (9)) have been synthesized and characterized by single crystal X-ray diffraction analysis. Although the Ln3+ions in 1–7have different radius, the trivalent lanthanide ions in 1–7show the same coordinated environment. The well-defined single crystal structures of 8and 9are first samples for formate-bridged Ln3+metallic complexes. The luminescent properties of solid samples of 2–5at room temperature and the magnetic property of 2have been also reported and discussed in this paper. [ABSTRACT FROM AUTHOR]

This paper describes the physical properties of the (Ni2)3+mixed-valence unit that is an excellent conductivity-enhanced tool for metal string complexes. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis and physical properties of a unique metal string complex isomer containing an asymmetric heterometallic backbone. [ABSTRACT FROM AUTHOR]

This paper deals with a notable halosulfite ion, (I2SO22−), which is a rare example of this inorganic anion species; the reaction of the platinum(ii) complex, [Pt(depe)2]I2with SO2afforded the complex, [Pt(depe)2](I2SO2) containing the rare anion; considering with the VSEPR concept, the structure of the anion could be interpreted as a distorted trigonal bipyramid. [ABSTRACT FROM AUTHOR]