Publications by authors named "Vukadin M Leovac"

A series of 18 novel N-Mannich bases derived from 5-adamantyl-1,2,4-triazole-3-thione was synthesized and characterized using NMR spectroscopy and X-ray diffraction technique. All derivatives were evaluated for their anticancer potential against four human cancer cell lines. Several tested compounds exerted good cytotoxic activities on K562 and HL-60 cell lines, along with pronounced selectivity, showing lower cytotoxicity against normal fibroblasts MRC-5 compared to cancer cells.

View Article and Find Full Text PDF

Three novel copper complexes with tridentate N2O ligand di(2-pyridil) ketone 1-adamantoyl hydrazone (Addpy) of the formula [Cu(II)2Cu(I)2(Addpy)2Br2(μ-Br4)] (1), catena-poly[CuCl(μ-Addpy)(μ-Cl)CuCl2]n (2) and [Cu(Addpy)(NCS)2] (3) were synthesized. Complexes are characterized by X-ray crystallography, spectral (UV-Vis, FTIR), electrochemical (CV) analyses, and magnetochemical measurements. Investigation of anticancer potential of Cu(II) complexes, mode of cell death, apoptosis, and inhibition of angiogenesis were performed.

View Article and Find Full Text PDF

The title compound, C9H13N4O3(+)·NO3(-), is the first structurally characterized Schiff base derived from semicarbazide and pyridoxal. Unusually for an unsubstituted semicarbazone, the compound adopts a syn conformation, in which the carbonyl O atom is in a cis disposition relative to the azomethine N atom. This arrangement is supported by a pair of hydrogen bonds between the organic cation and the nitrate anion.

View Article and Find Full Text PDF

New polymeric copper(II) complexes with two tridentate ONS thiosemicarbazone ligands containing substituted pyrazolone moiety were synthesized and characterized by means of spectroscopic, electrochemical and crystallographic techniques. While both ligands exist as different tautomers in the solid state and DMSO-d(6) solution, Cu(II) ion coordinates the ligands from the same tautomeric form with square-pyramidal geometry around each Cu atom. In the crystal structures, the copper(II) complex cation forms polymeric chains {[Cu(L)Cl](+)}(n) with a bridging chlorine atom.

View Article and Find Full Text PDF

The asymmetric unit of the title compound, (C(12)H(18)N(3)O(4))(2)[ZnCl(4)]·CH(3)OH, consists of two Girard reagent-based cations, a tetra-chlorido-zincate anion and a mol-ecule of methanol as solvate. These components are inter-connected in the crystal structure by an extensive network of O-H⋯O, N-H⋯O, C-H⋯O, O-H⋯N, O-H⋯Cl, N-H⋯Cl and C-H⋯Cl hydrogen bonds. The shortest inter-molecular inter-action is realized between the cation and anion [H⋯Cl = 2.

View Article and Find Full Text PDF

The title compound, [Cu(C(9)H(13)N(5)O(2))(CH(4)O)](NO(3))(2), consists of square-planar cationic complex units where the Cu(II) centre is coordinated by an N,N',O-tridentate pyridoxal-aminoguanidine Schiff base adduct and a methanol molecule. The tridentate ligand is a zwitterion exhibiting an almost planar conformation. The dihedral angles between the mean planes of the pyridoxal ring and the six- and five-membered chelate rings are all less than 2.

View Article and Find Full Text PDF

The title compound, [Ni(C(20)H(17)N(3)OP)(N(3))], is the first complex with a semicarbazide-based ligand having a P atom as one of the donors. The influence of the P atom on the deformation of the coordination geometry of the Ni(II) ion is evident but less expressed than in the cases of complexes with analogous seleno- and thiosemicarbazide ligands. The torsion angles involving the two bonds formed by the P atom within the six-membered chelate ring have the largest values [C-P-Ni-N = 24.

View Article and Find Full Text PDF

In the paper a joint experimental and theoretical study of 3,5-dimethyl-1H-pyrazole-1-carboxamidine (L) as well as its complexes CoL2(H2O)2(NO3)2 and NiL2(H2O)2(NO3)2 is reported. On the basis of FT-IR experiments and a DFT-derived scaled quantum mechanical force field the normal coordinate analysis of L was carried out. The FT-IR spectra of the two complexes were interpreted using the present assignment of L and computed vibrational data of the complexes.

View Article and Find Full Text PDF

A copper(II) complex with the pyridoxal-aminoguanidine (PL-AG) Schiff base adduct, as an organic compound of the very potent biological activity and promising pharmacological importance in the treatment of diabetic complications, has been prepared and characterized. The X-ray structural analysis of the [CuCl2(PL-AG)] complex showed that it has a distorted pseudo-square-pyramidal (4+1) structure with the tridentate ONN Schiff base in the equatorial plane, with the Cu-O(1), Cu-N(1) and Cu-N(3) bond lengths of 1.917(2)A, 1.

View Article and Find Full Text PDF

The title compound, [Ni(C(28)H(30)N(3)O(2)PS)], crystallizes with two independent molecules in the asymmetric unit. The Ni(II) atoms are in significantly deformed square-planar environments formed by an ONNP donor set from a thiosemicarbazide-based tetradentate ligand. The Ni(II) atom and the ONN donor atoms are nearly coplanar, while the P atom deviates from their mean planes by 0.

View Article and Find Full Text PDF

The title Cu(II) complex, [Cu2(NCS)4(C6H10N4)2], represents the first crystal structure of a polynuclear transition metal complex with the 3,5-dimethyl-1H-pyrazole-1-carboxamidine ligand (HL). It is compared with previously reported crystal structures of metal complexes with the same HL ligand. The molecule contains an eight-membered binuclear Cu2(NCS)2 ring, which is centrosymmetric and in a chair conformation.

View Article and Find Full Text PDF

In the crystal structure of the title complex, [Co(C(6)H(8)N(3)S)(3)], the Co(III) atom is octahedrally coordinated by three monodeprotonated bidentate 3,5-dimethyl-1H-pyrazole-1-thiocarboxamide ligands with two thiocarboxamide N atoms in axial positions. The asymmetric unit contains two molecules (A and B) and these molecules are arranged in chains in an alternating fashion connected by N-H..

View Article and Find Full Text PDF

The title compound, dibromo(3-hydroxy-5-hydroxymethyl-2-methyl-4-pyridinecarboxaldehyde semicarbazone-kappa(3)N(1),O(3),O(3'))copper(II), [CuBr(2)(C(9)H(12)N(4)O(3))], consists of discrete complex units with the tridentate pyridoxal semicarbazone ligand as a zwitterion in an almost planar configuration. The Cu(II) ions are in a distorted square-pyramidal coordination, with the equatorial Br atom at a distance of 2.4017 (6) A and the apical Br atom at a distance of 2.

View Article and Find Full Text PDF

Part XLIII: Novaković et al. (2002). The title complex, [Cu(NO(3))(C(10)H(14)N(4)O(2)S)(H(2)O)](NO(3)), is the first metal complex with a Schiff base derived from isothiosemicarbazide and pyridoxal (pyridoxal is 3-hydroxy-5-hydroxymethyl-2-methylpyridine-4-carboxaldehyde).

View Article and Find Full Text PDF

In the title compound, [ZnCl(C(2)H(7)N(3)S)(2)]Cl, the Zn(II) ion is five-coordinated in a distorted trigonal-bipyramidal arrangement, with the hydrazine N atoms located in the apical positions. The structure is stabilized by N[bond]H..

View Article and Find Full Text PDF