Shu-Hua Zhang

Dinuclear copper(II) complex and 1-D copper(II) complex with taurine Schiff base: synthesis, crystal structure, and properties

A dinuclear copper(II) compound, [Cu(btssb)(H2O)]2 · 4(H2O) (1), and a 1-D chain copper(II) compound, [Cu(ctssb)(H2O)] n (2) [where H2btssb is 2-[(5-bromo-2-hydroxy-benzylidene)-amino]-ethanesulfonic acid and H2ctssb is 2-[(3,5-dichloro-2-hydroxy-benzylidene)-amino]-ethanesulfonic acid], were prepared and characterized. Compound 1 crystallizes in the monoclinic space group P21/c, with a = 10.109(2) Å, b = 20.473(4) Å, c = 6.803(1) Å, β = 100.32(3)°, V = 1385.1(5) Å3, and Z = 2; R 1 for 1796 observed reflections [I > 2σ(I)] was 0.0357. The geometry around each copper(II) can be described as slightly distorted square pyramidal. The CuII ··· CuII distance is 5.471(1) Å. Compound 1 formed a 1-D network through O–H ··· O hydrogen bonds and 1-D water chains exist. The 1-D chain complex 2 crystallizes in the triclinic space group P 1, with a = 5.030(2) Å, b = 7.725(2) Å, c = 17.011(5) Å, α = 92.706(4)°, β = 97.131(4)°, γ = 102.452(3)°, V = 638.6(3) Å3, and Z = 2; R 1 for 1897 observed reflections [I > 2σ(I)] was 0.0171. In 2, Cu(II) was also a slightly distorted square pyramid formed by two oxygens and one nitrogen from ctssb, one oxygen from another ctssb, and one water molecule. The complex formed a 1-D chain through O–S–O bridge of ctssb ligand. The 1-D chain further constructed a double chain through O−H ··· O hydrogen bonds.

Preparation of 4-([2,2′:6′,2″-terpyridin]-4′-yl)-N,N-diethylaniline Ni II and Pt II complexes and exploration of their in vitro cytotoxic activities

Two metal complexes of NiLCl2 (1) and [PtLCl]Cl (2) with 4-([2,2:6,2″-terpyridin]-4-yl)-N,N-diethylaniline (L) were synthesized and characterized. 1 and 2 exhibited selective cytotoxicity to T-24xa0cells more than L, compared with the normal liver cell line (HL-7702). Various experiments showed that L, 1 and 2 caused T-24xa0cell cycle arrest at S phase, as shown by the down-regulation of cdc25 A, cyclin A, cyclin B and CDK2 and the up-regulation of p21, p27 and p53. Furthermore, complexes 1 and 2, especially complex 2, acted as telomerase inhibitors targeting c-myc G-quadruplex DNA and triggered cell apoptosis. In addition, 1 and 2 also caused mitochondrial dysfunction. Taken together, we found that 1 and 2 exerted their cytotoxic activity mainly via inhibiting telomerase by interaction with c-myc quadruplex and disruption of mitochondrial function.

Dodecanuclear water cluster in bowl: microwave-assisted synthesis of a heptanuclear cobalt(II) cluster

A heptanuclear double-bowl-like cluster [Co7(mmp)6(OH)6]2·(ClO4)2·12H2O (1·12H2O, Hmmp is 2-methoxy-6-methyliminomethyl-phenol) has been synthesized through the microwave-assisted reaction of Co(ClO4)2·6H2O with 2-hydroxy-3-methoxy-benzaldehyde (Hhmb) and methylamine in mixed solvent (acetonitrile : distilled water = 9 : 1) for 29 min. 1·12H2O was heated until 180 °C and it formed a non-water complex [Co7(mmp)6(OH)6]2·(ClO4)2 (1). The core of 1·12H2O can be described as a double bowl, while the dodecanuclear water cluster stands on the bowl. Magnetic investigations show that 1·12H2O and 1 display ferromagnetic interaction between cobalt ions. Moreover, 1 shows single molecular magnet behavior under 2 K. Magnetic studies indicate that hydrogen bond plays a vital role in transferring magnetic exchange effects. Graphical Abstract Using microwave assisted heating solvothermal method, a double-bowl-like heptanuclear cluster [Co7(mmp)6(OH)6]2·(ClO4)2·12H2O (1·12H2O) has been synthesized. We study the thermolysis of 1·12H2O through TG and XRD. 1 was formed through heating 1·12H2O. Magnetic behavior between 1 and 1·12H2O indicates hydrogen bonds playing an important role for transferring magnetic exchange effects. 1 shows a single molecular magnet behavior under 2u2009K.

Bis(4,6-dibromo-2-formylphenolato-κ2O,O′)bis(dimethyl sulfoxide-κO)nickel(II)

In the title compound, [Ni(C7H3Br2O2)2(C2H6OS)2], the NiII atom lies on a centre of inversion and is coordinated in an octaxadhedral geometry by four O atoms from two bidentate 4,6-dibromo-2-formylxadphenolate ligands and two O atoms from two dimethyl sulfoxide molxadecules. Short Br⋯Br contacts exist between molxadecules.

Triaqua­[2-(2-pyridylmethyl­eneamino)­ethanesulfonato-κ3N,N′,O]nickel(II) perchlorate monohydrate

In the title compound, [Ni(C8H9N2O3S)(H2O)3)]ClO4·H2O, the NiII atom is coordinated by the two N atoms [Ni—N = 2.054u2005(3) and 2.077u2005(3)u2005A] and one O atom [Ni—O = 2.070u2005(2)u2005A] from a tridentate 2-(2-pyridylmethylxadene)xadaminoxadethanesulfonate [or N-(2-pyridylmethylxadidene)xadtaurine] ligand and three water molxadecules [Ni—O = 2.025u2005(3)–2.081u2005(3)u2005A] in a distorted octaxadhedral geometry. An extensive three-dimensional network of O—H⋯O hydrogen bonds, involving perchlorate anions, and coordinating and non-coordinating water molxadecules, stabilizes the crystal packing.

Aqua{2-[(E)-(3,5-di­bromo-2-oxido­phenyl)­methyl­ene­amino]­ethanesulfonato-κ3O,N,O′}(1,10-phenanthroline-κ2N,N′)­nickel(II) ethanol solvate

The title compound, [Ni(C9H9Br2NO4S)(C8H8N2)(H2O)]·C2H5OH, was synthesized in a water–ethanol solution. In the structure, the Ni atom is six-coordinated by three ligands to form the neutral complex, in which the Ni atom has a distorted octahedral coordination geometry. Molecules form dimers through O—H⋯O hydrogen bonds.

Tris[2-eth­oxy-6-(methyl­imino­meth­yl)phenolato-κ2N,O1]cobalt(III) monohydrate

In the title compound, [Co(C10H12NO2)3]·H2O, the CoIII ion is coordinated by three O atoms and three N atoms from three bidentate 2-ethoxy-6-(methyliminomethyl)phenolate ligands in a slightly distorted octahedral environment. The water molecule connects two ligands by O—H⋯O hydrogen bonds. One terminal methyl group is disordered over two positions, with site-occupancy factors of 0.412u2005(15) and 0.588u2005(15).

Bis{2-[6-(1H-benzimidazol-2-yl-κN3)-2-pyridyl-κN]benzimidazolato-κN}manganese(II)

In the title compound, [Mn(C19H12N5)2], each MnII atom lies on a position of site symmetry 222 and has a distorted octahedral coordination geometry made up from six N atoms of two tridentate 2-[6-(1H-benzimidazol-2-yl)-2-pyridyl]benzimidazolate ligands. The complex molecules are linked into layers parallel to (001) by N—H⋯N hydrogen bonds, with the H atoms disordered over four symmetry-equivalent non-coordinated N atoms.

cis-Aqua­bis(2,4-dichloro-6-formyl­phenolato-κ2O,O′)(N,N-dimethyl­formamide-κO)nickel(II)

In the title compound, [Ni(C7H3Cl2O2)2(C3H7NO)(H2O)], the NiII ion is coordinated by four O atoms from two bidentate 2,4-dichloro-6-formylphenolate ligands, one O atom from a water ligand and one O atom from a dimethylformamide ligand in a slightly distorted octahedral environment. In the crystal structure, centrosymmetric dimers are formed though O—H⋯O and O—H⋯Cl hydrogen bonds; π–π stacking interactions, with a centroid–centroid distance of 3.796u2005(2)u2005Å, are also found.

[2‐(3,5‐Dibromo‐2‐oxidobenzyl­amino)‐3‐phenyl­propanoato‐κ3N,O,O′](1,10‐phenanthroline‐κ2N,N′)zinc(II) dihydrate

In the title complex, [Zn(C16H13Br2NO3)(C12H8N2)]·2H2O or [Zn(L)(phen)]·2H2O, [LH2 = 2-(3,5-dibromo-2-hydrxadoxy-benzylxadamino)-3-phenylpropionic acid and phen = 1,10-phenanthroline], the ZnII atom is coordinated in a slightly distorted square-pyramidal geometry by two O atoms and one N atom from an L2− ligand and two N atoms from a phen ligand. One of the carboxylxadate O atoms is in the apical position. In the crystal structure, complex molxadecules are linked into a chain along the c axis through N—H⋯O hydrogen bonds; the water molxadecules are connected to the chains via O—H⋯O hydrogen bonds.