Novel Octahedral Nickel (II) Complex with Flexible Piperazinyl Moiety Exhibits Potent Cytotoxic Effect Along with Anti-Migratory and Anti-Metastatic Effect on Human Cancer Cells.

Synthesis of non-platinum transition metal complexes with N,O donor chelating ligand for application against pathogenesis of cancer with higher efficacy and selectivity is currently an important field of research. We assessed the anti-cancer effect of a mixed ligand Ni(II) complex on human breast and lung cancer cell lines in this investigation. Mononuclear mixed ligand octahedral Ni(II) complex [NiL(NO)(MeOH)] complex (1), with tri-dentate phenol-based ligand 2,4-dichloro-6-((4-methylpiperazin-1-yl) methyl) phenol (HL) along with methanol and nitrate as ancillary ligand was prepared.

Tetra-, tri-, and mononuclear manganese(II/III) complexes of a phenol-based N2O2 capping ligand: use of carboxylates as ancillary ligands in tuning the nuclearity of the complexes.

Manganese(II/III) complexes of a phenol-based tetradentate ligand L(2-) [H(2)L = N,N'-dimethyl-N,N'-bis(2-hydroxy-3,5-dimethylbenzyl)-ethylenediamine], namely, [Mn(4)(L)(2)(PhCOO)(6)] (1), [Mn(3)(L)(2)(CH(3)CH(2)COO)(2)(OMe)(2)].H(2)O (2), and [Mn(L){(CH(3))(3)CCOO}(CH(3)OH)].CH(3)OH (3), have been synthesized.

Reporting a new class of divanadium(V) compounds connected by an unsupported hydroxo bridge.

Dinuclear oxovanadium(V) compounds [LV(V)O(mu-OH)OV (V)L](PF6) [H2L = N,N'-tert-ethylene bis(salicylideneimine) (H 2Salen) and its derivatives] ( 1- 3) have been obtained by aerial oxidation of V (IV)OL precursors in THF in the presence of added NH 4PF 6. The oxidized vanadium(V) probably extracts an OH (-) ligand from the residual moisture in the solvent and is retained as an unsupported hydroxo-bridge between the metal centers of these compounds as confirmed by single-crystal X-ray diffraction analyses. The molecules of 1- 3 have centrosymmetric structures with each vanadium center having a distorted octahedral geometry.

Tetra- and dinuclear nickel(II)-vanadium(IV/V) heterometal complexes of a phenol-based N2O2 ligand: synthesis, structures, and magnetic and redox properties.

The tetra- and binuclear heterometallic complexes of nickel(II)-vanadium(IV/V) combinations involving a phenol-based primary ligand, viz., N,N'-dimethyl-N,N'-bis(2-hydroxy-3,5-dimethylbenzyl)ethylenediamine (H2L1), are reported in this work. Carboxylates and beta-diketonates have been used as ancillary ligands to obtain the tetranuclear complexes [Ni(II)(2)V(V)(2)(RCOO)(2)(L(1))(2)O(4)] (R = Ph, 1; R = Me(3)C, 2) and the binuclear types [(beta-diket)Ni(II)L(1)V(IV)O(beta-diket)] (3 and 4), respectively.

Bi- and trinuclear copper(II) complexes of a sterically constrained phenol-based tetradentate ligand: syntheses, structures, and magnetic studies.

Copper(II) complexes (1-3) of a sterically constrained phenol-based tetradentate N(2)O(2) ligand 1,4-bis(2-hydroxy-3,5-dimethylbenzyl)piperazine (H(2)L) have been reported. The associated anions of the copper(II) ion precursors have profound influence on the stoichiometry of the products. Thus, with perchlorate ion, the product is a binuclear compound [Cu(2)L(2)] (1), while with coordinating anions viz.

Honeycomb nets with interpenetrating frameworks involving iminodiacetato-copper(II) blocks and bipyridine spacers: syntheses, characterization, and magnetic studies.

Three coordination polymers of copper(II), viz. ([Cu(ida)(4,4'-bipyH)]ClO(4))( proportional, variant ) (1), ([Cu(2)(ida)(2)(micro-4,4'-bipy)].2H(2)O)( proportional, variant ) (2), and [Cu(2)(ida)(2)(bpa)]( proportional, variant ) (3) have been synthesized by the process of self-assembly using Cu(ida) [ida = iminodiacetate(2-)] as the building block and 4,4'-bipyridyl and 1,2-bis(4-pyridyl)ethane (bpa) as linkers.

Equilibrium studies in solution involving nickel(II) complexes of flexidentate Schiff base ligands: isolation and structural characterization of the planar red and octahedral green species involved in the equilibrium.

Three new flexidentate 5-substituted salicylaldimino Schiff base ligands (L1-OH-L3-OH) based on 1-(2-aminoethyl)piperazine (X=H, L1-OH; X=NO2, L2-OH; and X=Br, L3-OH) and their nickel(II) complexes (1a, 1b, 2, and 3) have been reported. The piperazinyl arm of these ligands can in principle have both boat and chair conformations that allow the ligands to bind the Ni(II) center in an ambidentate manner, forming square-planar and/or octahedral complexes. The nature of substitution in the salicylaldehyde aromatic ring and the type of associated anion in the complexes have profound influences on the coordination geometry of the isolated products.

Adduct formation between alkali metal ions and anionic LV(V)O(2)(-) (L(2-) = tridentate ONS ligands) species: syntheses, structural investigation, and photochemical studies.

Syntheses of alkali metal adducts [LVO(2)M(H(2)O)(n)] (1-7) (M = Na(+), K(+), Rb(+), and Cs(+); L = L(1)(-)L(3)) of anionic cis-dioxovanadium(V) species (LVO(2)(-)) of tridentate dithiocarbazate-based Schiff base ligands H(2)L (S-methyl-3-((5-(R-2-hydroxyphenyl))methyl)dithiocarbazate, R = H, L = L(1); R = NO(2), L = L(2); R = Br, L = L(3)) have been reported. The LVO(2)(-) moieties here behave like an analogue of carboxylate group and have displayed interesting variations in their binding pattern with the change in size of the alkali metal ions as revealed in the solid state from the X-ray crystallographic analysis of 1, 3, 6, and 7. The compounds have extended chain structures, forming ion channels, and are stabilized by strong Coulombic and hydrogen-bonded interactions.