Browsing by Author "Ciumacov, Iurie"

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Coordination compounds of cobalt, nickel, copper and zinc with thiosemicarbazone and 3-phenylpropenal semicarbazone [Articol]
(2006) Samusi, Nina; Gulea, Aurelian; Țapcov, Victor; Ciumacov, Iurie; Roșu, Tudor
Hydrates of 3-phenylpropenal thiosemicarbazone (HL•H2O) and semicarbazone (HL'•H2O) react in methanol with cobalt, nickel, copper, and zinc chlorides, nitrates, and acetates to form coordination compounds MX2•2HL•nSolv [M = Co, Ni, Cu, Zn; X = Cl, NO3; HL = C6H5CH=CH-CH=N-NHC(O)NH2; n = 0-3; Solv = H2O, CH3OH], CuX2•HL• nH2O [M = Ni, Cu; n = 0, 1], ML2•nH2O and ML'•nH2O [M = Co, Ni, Zn; HL' = C6H 5CH=CH-CH=N-NHC(O)NH2; n = 0-3]. In the presence of amines (A = C5H5N, 2-CH3C5H4N, 3-CH3C5H4N, and 4-CH3C 5H4N) these reactions yield the complexes Cu(A)LCl•CH3OH and M(A)LX•nH2O [M = Cu, Ni; X = Cl, NO3; n = 0-2]. The copper complexes with the amine ligands are of polynuclear structure, and other complexes are monomeric. Carbazones (HL and HL') are included in the complexes as bidentate N,S-and N,O-ligands. The thermolysis of the complexes involves the stages of removing solvent crystallization molecules (70-90°C), deaquation (150-170°C), and full thermal decomposition (500-580°C).
Coordination compounds of cobalt, nickel, copper, and zinc with 2-bromo-3-phenylpropenal benzoylhydrazone and thiosemicarbazone [Articol]
(2009) Samusi, Nina; Ciumacov, Iurie; Țapcov, Victor; Bocelli, Gabrielle; Simonov, Iurie; Gulea, Aurelian
By X-ray structural analysis the crystal structure of 2-bromo-3- phenylpropenal benzoylhydrazone (HL) was determined. The molecule is not flat. In the crystal the HL molecules form infinite chains with reciprocal van der Waals interaction. 2-Bromo-3-phenylpropenal hydrazone (HL) and thiosemicarbazone (HL') react with cobalt, nickel, copper and zinc chlorides, nitrates and acetates to form coordination compounds of the composition Cu(HL)(L)2 [HL = C6H5-CH=CBr-CH=N-NH-C(O)-C6H 5], MX2•2 HL'•nH2O [M = Co, Ni, Cu, Zn; X = Cl, NO3, HL' = C6H5-CH=CBr-CH=N-NH-C(S) -NH2; n = 0-3], MX2•HL•n H2O [M = Ni, Cu; n = 0, 1], and ML'2•nH2O [M = Co, Ni, Zn; n = 0-3]. The same reactions in the presence of amines (A = C5H 5N, 2-CH3C5H4N, 3-CH 3C5H4N, 4-CH3C5H 4N) afford complexes of the composition CuALCl and MALX•n H 2O [M = Cu, Ni; X = Cl, NO3; n = 0-2]. Structure of the coordination node in the amine-containing copper derivatives is polynuclear, in complexes Cu(HL)(L)2 is octahedral, in other compounds it is tetrahedral. The azomethines (HL and HL') in these complexes behave as bidentate N,O and N,S ligands. Thermolysis of the complexes includes a step of dehydration (60-90°C) and complete thermal decomposition (430-590°C).
Coordination compounds of copper (II) nitrate with products of aminotris(hydroxymethyl)methane condensation with salicyl- and 5-nitrosalicylaldehydes: Synthesis and crystal structures [Articol]
(2005) Ciumacov, Iurie; Țapcov, Victor; Simonov, Iurie; Antoșciac, Boris; Bocelli, Gabrielle; Perrin, Monique; Starnicova, Zoia; Samusi, Nina; Gulea, Aurelian
The crystal structures of copper(II) nitrate complexes with 2-(2-hydroxybenzylideneamino)-2-hydroxymethylpropane-1,3-diol (HL) and 2-hydroxymethyl-2-(2-hydroxy-5-nitrobenzylideneamino)propane-1,3-diol (HL 1) were determined. The resulting complexes were formulated as [Cu3OL3(H2O2]NO3 • 3H2O (I) and [Cu(H2O)L1]NO3 (II). The crystals of I are monoclinic, a = 17.809(4) Å, b = 30.549(6) Å, c = 18.962(4) Å, β = 115.36(3)°, space group Cc, Z = 8, R = 0.0482. Complex I is composed of two independent three-dimensional μ 3-oxo complexes; the coordination polyhedron of the copper atoms in both compounds is an elongated tetragonal bipyramid. The coordination polyhedron of the third Cu atom is a tetragonal pyramid. The bases of the pyramids are composed of the oxygen atoms of the phenol and alcohol OH groups, the imine N atom of ligand L, and μ 3-oxo atoms. The phenol and water O atoms serve as the apices in both the tetragonal bipyramids. The crystals of II are triclinic, a = 6.062(1) Å, b = 7.701(2) Å, c = 16.162(3) ̊, α = 88.15(3)°, β = 84.94(3)°, γ = 78.13(3)°, space group P1̄, Z = 2, R = 0.0272. Complex II is composed of polymer chains formed by coordination bonds between the copper atom and two O atoms of the amino alcohol in the azomethine of the neighboring complex connected to the initial one by translation along the x axis. These chains are linked through hydrogen bonds involving the oxygen atoms of the NO2 groups. The benzene rings of the azomethine ligands of the adjoining complexes from different chains are antiparallel to each other. The coordination polyhedron of the central atom is an elongated tetragonal bipyramid. Its equatorial plane is formed by the phenol O atom, one of the alcohol O atoms, the N atom of ligand L1, and the O atom of the amino alcohol in the neighboring complex. The apices are the O atom of the water molecule and the O atom of the amino alcohol in the neighboring azomethine molecule. In complexes I and II, the outer-sphere nitrato group mainly serves to unite trimers and polymers in the crystal by means of hydrogen bonds.
Coordination compounds of copper(II) with substituted 3-{[(2-hydroxyphenyl) methylidene]amino}propane-1,2-diols [Articol]
(2013) Gulea, Aurelian; Ciumacov, Iurie; Graur, Vasilii; Țapcov, Victor
3-{[(2-Hydroxyphenyl)methylidene]amino}propane-1,2-diol, its 5-chloro-,5-bromo-, 5-nitro-, 3-methoxy derivatives, and 3-{[(2-hydroxynaphthyl- 1)methylidene]amino}propane-1,2-diol react with hydrates of copper(II) chloride, bromide and nitrate in ethanol to form coordination compounds Cu(L)X·nH2O. Template condensation reaction between 3-aminopropane-1,2-diol and 2,3-, 2,4- or 2,5-dihydroxybenzaldehyde in the presence of copper(II) nitrate trihydrate results in similar compounds Cu(L)NO3·nH2O. Structure of some of the condensation products was identified by X-ray analysis. Thermolysis of the substances obtained occurs through the dehydration step (70-90 C) and complete thermal decomposition (290-560 C).
Crystal structure of 4,4-bipyridine-containing complexes of copper(II) nitrate with 1-[(2-Hydroxyethylimino)methyl]naphthalen-2-ol and 2-[(2-hydroxyethylimino)methyl]phenol [Articol]
(2009) Ciumacov, Iurie; Țapcov, Victor; Petrenko, Peter A.; Popovschi, Liliana; Simonov, Iurie; Bocelli, Gabrielle; Antoșciac, Boris; Paraschivescu, Andrei; Gulea, Aurelian
The crystal structures of (μ-4,4-bipyridine)-di(nitrato-1-[(2- hydroxyethylimino)methyl]naphthalen-2-olocopper (I) and catena-di(μ-4,4'- bipyridine)di(μ-4,4'-bipyridine)-di(nitrato-2-[2-(hydroxyethylimino) methyl]phenolocopper)diaquacopper(II) nitrate (II) were determined. In the crystal of I, each of the two copper atoms coordinates a singly deprotonated tridentate azomethine molecule, a nitrate ion, and bipyridine, which functions as a bridge between the central atoms. The copper coordination polyhedron is a slightly distorted tetragonal pyramid with the base formed by the imine and bipyridine nitrogen atoms and the phenol and alcohol oxygen atoms. The axial site in the pyramid is occupied by the oxygen atom of the monodentate nitrate groups. In the trinuclear structure II with C2 crystal chemical symmetry, the terminal coordination unit is composed through copper coordination of monodeprotonated 2-[2-(hydroxyethylimino)methyl]phenol, bipyridine, and the nitrate anion. In the crystal, the trinuclear molecules form infinite ribbons along the z axis in which the pyridine molecules perform the bridging function. The central copper atom has an octahedral configuration formed by the nitrogen atoms of four 4,4'-bipyridine molecules and oxygen of two water molecules
Crystal structure of copper sulfate and thiocyanate complexes with 5-bromo-and 5-nitrosalicylaldehyde thiosemicarbazones [Articol]
(2008) Ciumacov, Iurie; Jeanneau, Erwann; Bejenari, Natalia; Țapcov, Victor; Gulea, Aurelian
The crystal structures of (5-bromosalicylidenethiosemicarbazido) aquacopper(II) sulfato(5-bromosalicylidenethiosemicarbazido)aquacuprate(II) tetrahydrate (I), (5-nitrosalicylidenethiosemicarbazido) dimethylsulfoxide(methanol)copper(II) sulfate (II), and catena(μ-thiocyanato) (5-nitrosalicylidenethiosemicarbazido)copper(II) (III) were determined. In structure I, the independent part of the unit cell contains four water molecules of crystallization and the cation-anion complex [Cu(H2O)(L)] [Cu(H2O)(L)(SO4)] containing two nonequivalent copper complexes (A and B). In these, the metal atom coordinates monodeprotonated 5-bromosalicylaldehyde thiosemicarbazone (HL) and water molecules, and in anion B also a sulfate ion. In complex ions A and B, sulfur, azomethine nitrogen, and phenolic oxygen of the salicylidene thiosemicarbazone fragment, and also water molecule form a distorted planar square around the metal atom. The axial vertex of the pyramid in anion B is occupied by the oxygen atom of the monodentate sulfate anion. In structure II, the independent part of the unit cell contains the (5-nitrosalicylidenethiosemicarbazido)dimethylsulfoxide(methanol)copper(II) complex cation and the sulfate anion. The coordination polyhedron of the central atom is a slightly distorted tetragonal pyramid whose base is formed by sulfur, azomethine nitrogen, phenolic oxygen of thiosemicarbazone, and dimethyl sulfoxide oxygen. The axial position is occupied by the methanol oxygen atom. In structure III, the copper atom coordinates 5-nitrosalicylaldehyde thiosemicarbazone and the thiocyanate ion, which combines complexes into infinite polymer chains along the [010] direction. The copper coordination polyhedron in III is a slightly distorted tetragonal pyramid whose base is formed by sulfur, azomethine nitrogen, phenolic oxygen of thiosemicarbazone, and nitrogen of thiocyanate ion, the axial vertex is occupied by sulfur of thiocyanate ion of the neighboring complex.
Crystal structure of nitrate tris (4-allylthiosemicarbazide)-chromium(III) hydrate [Articol]
(2016) Ciumacov, Iurie; Petrenko, Peter A.; Graur, Vasilii; Țapcov, Victor; Gulea, Aurelian
The crystal structure of nitrate tris(4-allylthiosemicarbazide)chromium(III) hydrate [CrL3](NO3)3(H2O)1.05 (I), where L is 4-allylthiosemicarbazide, is determined. The asymmetric unit of the cell of the crystal structure of I contains a complex of a chromium ion with three bidentate coordinated molecules L. The outer coordination sphere of the central atom contains a disordered water molecule and three nitrate ions. The coordination polyhedron of the chromium atom in complex I is an octahedron. In the crystal, the complexes of the compound under study are joined with each other by the outer-sphere nitrato groups into a three-dimensional branched net of hydrogen bonds.
Crystal Structure of the Acetic Acid Solvate of N-(Prop-2-En-1-Yl)-2-(Pyrid-2-Ylmethylidene) Hydrazinecarboselenoamide [Articol]
(2018) Ciumacov, Iurie; Petrenko, Peter A.; Graur, Vasilii; Țapcov, Victor; Gulea, Aurelian
The crystal structure of the acetic acid solvate of N-(prop-2-en-1-yl)-2-(pyrid-2- ylmethylidene)hydrazinecarboselenoamide (I) is determined. The asymmetric unit of the unit cell in its crystal structure contains a molecule of I and an acetic acid molecule. The molecule of I is non-planar; the angle between the mean square planes of hydrazinecarboselenoamide A(Sе1N1N2N3С1C2) and prop-2-en-1-yl (С5С6C7) moieties is 82.3°. In the crystal, the acetic acid molecules link the molecules of I in endless chains along the [010] direction.
Crystal structures of 3-phenylpropenal thiosemicarbazone and its nickel and zinc chelates [Articol]
(2006) Ciumacov, Iurie; Samusi, Nina; Bocelli, Gabrielle; Suponițchi, Chiril; Țapcov, Victor; Gulea, Aurelian
3-Phenylpropenal thiosemicarbazone hydrate C6H 5-HC=CH-CH=N-NH-C(S)-NH2 • H2O (HL • H2O, I) and two chelates [Ni(L)2] • nCH3OH (II) and [Zn(L)2] (III) are studied by X-ray diffraction. The crystals of I are orthorhombic: a = 6.227(1) Å, b = 7.763(2) Å, c = 25.585(5) Å, β = 90°, space group P212 121, Z = 4, R = 0.0426. A nonplanar molecule of I has an E conformation. The crystals of II are triclinic: a = 6.551(2) Å, b = 10.752(3) Å, c = 10.885(3) Å, α = 64.751(5)°, β = 82.753(5)°, γ = 89.857(5)°, space group, Z = 1, R = 0.0661. In a centrosymmetric molecule of II, the central atom coordinates two deprotonated ligands L through the immine nitrogen atom and thioamide sulfur atom at the vertices of a distorted square. The crystals of III are monoclinic: a = 25.342(2) Å, b = 9.150(2) Å, c = 21.340(3) Å, α = 90°, β = 111.84(2)°, γ = 90°, space group C2/c, Z = 8, R = 0.0556. In a molecule of complex III, two deprotonated bidentate ligands L are coordinated by the zinc ion through the immine nitrogen atoms and thioamide sulfur atoms to form a distorted tetrahedron at the central atom. In both II and III, ligand L after coordination by the metal ion changes the E conformation with respect to the N(1)-C(2) bond for the Z conformation. In crystals I-III, molecules are packed to form infinite layers parallel to the planes (001) and (010)
Crystal structures of [N′-(2- oxidobenzylidene)-N-(prop-2-en-1-yl carbamohydrazonothioato(2-)](1,10- phenanthroline)copper and [N′-(2- oxidobenzylidene)-N-(prop-2-)- en-1-yl)- carbamohydrazonothioato(2-)](2,2′- bipyridine)copper hemihydrates [Articol]
(2022) Ciumacov, Iurie; Graur, Vasilii; Ulchina, Ianina; Smaglii, Vadim; Gulea, Aurelian; Garbuz, Olga; Țapcov, Victor
The crystal structures and biological properties of [N′-(2-oxidobenzylidene)-N-(prop-2-en-1-yl)-carbamohydrazonothioato(2-)](1,10-phenanthroline)copper hemihydrate [Cu(1,10-Phen)(L)]·0.5H2O (I) and [N′-(2-oxidobenzylidene)-N-(prop-2-en-1-yl)-carbamohydrazonothioato(2-)](2,2′-bipyridine)copper hemihydrate [Cu(2,2′-BPy)(L)]·0.5H2O (II), where Н2L is 2-(2-hydroxybenzylidene)-N-(prop-2-en-1-yl)hydrazinecarbothioamide, are determined. The asymmetric unit of the unit cell in the crystal structures of I and II contains a copper complex with bidentate amine and a ligand coordinated by the azomethine nitrogen atom, the deprotonated phenolic oxygen atom, and the sulfur atom in the thiol form. The coordination polyhedron of the copper atom in compounds I and II is a distorted tetragonal pyramid. Obtained coordination compounds I and II exhibit antimicrobial and antifungal activities and have minimum inhibitory concentration and bactericidal concentration values in a range of 1.5-500 µg/mL. The study of the antioxidant activity shows that compounds I and II are less active than uncoordinated thiosemicarbazone H2L, but more active than trolox used in medical practice.
Crystal structures of nitrato-{2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo}aquacopper and chloro-{2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo}copper [Articol]
(2015) Ciumacov, Iurie; Paholnițcaia, Anastasia; Petrenko, Peter A.; Țapcov, Victor; Poirier, Donald; Gulea, Aurelian
Two crystal modifications of nitrato-{2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo}aquacopper (I and II) and two modifications of chloro-{2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo}copper (III and IV) have been synthesized and studied by X-ray diffraction. In structures I and II, the copper atoms coordinate a monodeprotonated molecule of the organic ligand, nitrate ions, and a water molecule. In crystals of I, the complexes are monomeric, whereas complexes II are linked via nitrate ions to form polymeric chains. In both structures the coordination polyhedron of the copper atom can be described as a distorted tetragonal bipyramid—(4 + 1 + 1) in I and (4 + 2) in II. These coordination polyherdra have different compositions. In structures III and IV, the metal atoms coordinate a monodeprotonated {2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazole molecule and chloride ions. In III the complex-forming ion has square-planar coordination geometry, whereas structure IV consists of centrosymmetric dimers with two bridging chlorine atoms. It was found that nitrato-{2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo}aquacopper possesses antitumor activity.
Crystal structures of nitrato-{4-bromo-2-[(2-hydroxyethylimion)methyl] phenolo}-(3,5-dibromopyridine)copper and nitrato-{2,4-dibromo-6-[(2- hydroxyethylimino)methyl]phenolo}-(3,5-dibromopyridine)copper [Articol]
(2006) Ciumacov, Iurie; Țapcov, Victor; Bocelli, Gabrielle; Neburger, Markus; Gulea, Aurelian
The crystal structures of nitrato-{4-bromo-2-[2-hydroxyethylimino)methyl] phenolo}-(3,5-dibromopyridine)copper (I) and nitrato-{2,4-dibromo-6-[(2- hydroxyethylimino)methyl]phenolo}-(3,5-dibromopyridine)copper (II) are determined. The crystals of compound I are orthorhombic: a = 14.157(3) Å, b = 15.420(3) Å, c = 17.494(4) Å, space group Pbca, Z = 8, R = 0.067. The crystals of compound II are monoclinic: a = 10.675 Å, b = 13.973 Å, c = 14.007 Å, β = 111.92°, space group P2 1/n, Z = 4, R = 0.0464. In the structures of compounds I and II, the copper atom coordinates, correspondingly, singly deprotonated 4-bromo-2-[(2-hydroxyethylimino)methyl]phenol and 2,4-dibromo-6-[(2- hydroxyethylimino)methyl]phenol molecules, and 3,5-dibromopyridine, and the nitrate ion. The coordination polyhedron of the copper ion in complexes I and II is a slightly distorted tetragonal pyramid. The bases of the pyramids are formed by the imine and pyridine nitrogen atoms and the phenolic and alcoholic oxygen atoms, and the axial vertices are occupied by the oxygen atoms of the monodentate nitrato groups. In the complexes under study, the six-membered metallocycles have asymmetric gauche conformation. In crystal, complexes I are united, due to the slip plane a, through bifurcate hydrogen bonds into infinite chains along the direction [100]. Complexes II in crystal form two-dimensional networks by means of hydrogen bonds.
Introducing N-Heteroaromatic Bases into Copper(II) Thiosemicarbazon Complexes: A Way to Change their Biological Activity [Articol]
(2022) Ulchina, Ianina; Graur, Vasilii; Țapcov, Victor; Ciumacov, Iurie; Garbuz, Olga; Burduniuc, Olga; Ceban, Emil; Gulea, Aurelian
Three new copper(II) complexes, [Cu(1,10-Phen)(L)] (1), [Cu(2,2’- Bpy)(L)] (2) and [Cu(3,4-Lut)(L)] (3), where H2L=2-[(2,4- dihydroxyphenyl)methylidene]-N-(prop-2-en-1-yl)hydrazine-1- carbothioamide, 1,10-Phen=1,10-phenanthroline, 2,2’-Bpy= 2,2’-bipyridine, 3,4-Lut=3,4-lutidine, have been synthesized and characterized by elemental analysis, FTIR spectroscopy and single crystal X-ray crystallography (1, 2). All compounds are mononuclear. The introduction of a monodentate N-heteroaromatic base (3,4-dimethylpyridine) has led to a significant increase of antimicrobial activity against Gram-negative Escherichia coli and antifungal activity against Candida albicans compared to the pro-ligand and the precursor complex [Cu- (L)H2O]. The introduction of bidentate N-heteroaromatic bases did not lead to such increase of antimicrobial and antifungal activities. Moreover, complex 3 surpasses the inhibitory activity of tetracycline toward Enterobacter cloacae and the inhibitory activity of fluconazole toward Candida parapsilosis and Cryptococcus neoformans. The study of antioxidant activity against cation radicals ABTS* + showed that complexes 1–3 are more active than Trolox, but only introduction of the monodentate Nheteroaromatic base (3,4-dimethylpyridine) led to the increase of antioxidant properties compared to the precursor complex.
Nickel (II) Complexes with Pentane-2,4-dione Bis(4-allylthiosemicarbazone) [Articol]
(2020) Gulea, Aurelian; Graur, Vasilii; Ciumacov, Iurie; Petrenko, Peter; Garbuz, Olga; Țapcov, Victor; Gudumac, Valentin
Reaction of pentane-2,4-dione with N-(prop-2-en-1-yl)hydrazinecarbothioamide at a 1: 2 molar ratio in ethanol resulted in the formation of a pyrazole derivative. The latter reacted with nickel perchlorate at a 1: 1 molar ratio to form the nickel complex with pentane-2,4-dione bis(4-allylthiosemicarbazone). The same type of nickel complex was obtained as a result of N-(prop-2-en-1-yl)hydrazinecarbothioamide reaction with pentane-2,4-dione and nickel nitrate at a 2: 1: 1 molar ratio. Antimicrobial, antifungal, antioxidant, and anticancer activities of the obtained compounds were studied.
Novel 2-formylpyridine 4-allyl-S-methylisothiosemicarbazone and Zn(II), Cu(II), Ni(II) and Co(III) complexes: Synthesis, characterization, crystal structure, antioxidant, antimicrobial and antiproliferative activity [Articol]
(2019) Balan, Greta; Usataia, Irina; Graur, Vasilii; Ciumacov, Iurie; Petrenko, Peter; Gudumac, Valentin; Gulea, Aurelian; Pahonțu, Elena; Burduniuc, Olga
New zinc (II), copper (II), nickel (II) and cobalt (III) complexes, [Zn (HL)2]I2 (1), [Cu (HL)Cl2] (2), [Cu (HL)Br2] (3), [Cu (HL)(H2O)2](ClO4)2 (4), [Ni (HL)2]I2·H2O (5), [Co(L)2]Cl (6), [Co(L)2]NO3 (7), [Co(L)2]I·[Co(L)2](I3) (8) were obtained with 2-formylpyridine 4-allyl-S-methylisothiosemicarbazone (HL). The isothiosemicarbazone ligand was characterized by NMR (1H and 13C), IR spectroscopy and X-ray diffraction. All the complexes were characterized by elemental analysis, IR, UV–Vis, ESI-MS spectroscopy, molar conductivity, magnetic susceptibility measurements. X-ray diffraction analysis on the monocrystal and powder elucidated the structure of the complexes 1, 5, 7 and 8. The ligand and the complexes were tested for their antioxidant and antimicrobial activity against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Candida albicans. Also, the antiproliferative properties of these compounds on human leukemia HL-60, human cervical epithelial HeLa, human epithelial pancreatic adenocarcinoma BxPC-3, human muscle rhabdomyosarcoma spindle, large multinucleated RD cells and normal MDCK cells have been investigated. The nickel complex 5 and cobalt complexes 6, 7 showed promising antiproliferative activity and low toxicity.
Synthesis and antileukaemia activity of N-(2,4-dimethylphenyl)hydrazine carbothioamide and its azomethine derivatives [Articol]
(2012) Gulea, Aurelian; Barba, Alic; Jalbă, Alexandru; Poirier, Donald; Petrenko, Peter A.; Ciumacov, Iurie; Sargun, Artur
Prezenta lucrare conţine date despre sinteza, caracterizarea şi evaluarea in vitro a activităţii biologice a N-(2,4-dimetilfenil)hidrazinocarbotioamidei şi a cinci derivaţi azometinici ai acesteia, obţinuţi prin condensarea N-(2,4-dimetilfenil)hidrazincarbotioamidei cu diferiţi compuşi carbonilici. Compoziţia şi structura cristalină a compuşilor sintetizaţi a fost determinată cu ajutorul spectroscopiei 1H, 13C RMN şi a difracţiei cu raze X a monocristalelor. Toţi compuşii obţinuţi au fost testaţi ca inhibitori ai proliferării celulelor de leucemie umană HL-60. A fost stabilit că N-(2,4-dimetilfenil)-2-(tiofen- 3-ilmetilen)hidrazinocarbotioamida şi N-(2,4-dimetilfenil)-2-(2-hidroxibenziliden) hidrazinocarbotioamida sunt cei mai activi agenţi antiproliferativi obţinuţi în acest studiu.
Synthesis and structure of Di(μ-O phenoxy)-bisnitrato-2-[2- (hydroxyethylimino)-methyl]-phenoloimidazolecopper [Articol]
(2004) Ciumacov, Iurie; Antoșciac, Boris; Țapcov, Victor; Bocelli, Gabrielle; Gulea, Aurelian
The crystal structure of di(μ-O phenoxy)-bisnitrato-2-[2- (hydroxyethylimino)-methyl]-phenoloimid-azolecopper was determined. The crystals are monoclinic: a = 10.222(2) , b = 13.810(3) , c = 10.620(2) , β =103.67(3)°, space group P2 1/n, Z = 2, R = 0.050. The copper atom coordinates the singly deprotonated 2-[2-(hydroxyethylimino)-methyl]-phenol molecule, imidazole, and nitrate ion. The coordination polyhedron of the central atom is an extended tetragonal bipyramid with imine and imidazole nitrogen atoms and phenol and alcohol oxygen atoms lying in its base. One axial vertex of the bipyramid is occupied by the oxygen atom of the nitrato group and the other vertex, by phenol oxygen atom of the neighboring complex joined with the initial complex by the symmetry center. Two bridging phenol oxygen atoms unite the complexes into a centrosymmetrical dimer.
Synthesis, characterization, andbiological properties of the copper(II) complexes with novellig and: N-[4-({2-[1-(pyridin2-yl)ethylidene] hydrazinecarbothioyl}amino) phenyl] acetamide [Articol]
(2023) Rusnac, Roman; Garbuz, Olga; Ciumacov, Iurie; Țapcov, Victor; Hureau, Christelle; Istrati, Dorin; Gulea, Aurelian
For the first time, a thiosemicarbazone-type ligand containing a paracetamol structural unit was synthesized. Five new coordination compounds based on copper(II) salts: [Cu(L)CH3COO] (1), [{Cu(L)Cl}2]·H2O (2), [Cu(L)H2O·DMF]NO3 (3), [Cu(L)Br] (4), [Cu(L)H2O]ClO4 (5), were obtained, where HL is N-[4-({2-[1-(pyridin-2-yl)ethylidene]hydrazinecarbothioyl}amino)phenyl]acetamide. The new HL was characterized by NMR, FTIR, spectroscopy, and X-ray crystallography. All copper(II) coordination compounds were characterized by elemental analysis, FTIR, EPR spectroscopy, and molar electrical conductivity. Furthermore, single crystal X-ray diffraction analysis elucidated the structures of thiosemicarbazone HL as well as complexes 1–3. All compounds were tested for antimicrobial, antifungal, and antioxidant activities, and their toxicity to Daphnia magna was studied. Biological evaluation has revealed that most of the synthesized compounds demonstrate promising antibacterial, antifungal, and antioxidant activities. In many cases, their antibacterial/antifungal activity is comparable to that of certain drugs used in medicine for these purposes, and in some cases, even surpasses them. HL and complexes 2–5 exhibit antioxidant activity that surpasses that of Trolox. Furthermore, HL and complex 2 display virtually no toxicity to D. magna.
Synthesis, characterization, crystal structure of novel Cu (II), Co (III), Fe (III) and Cr (III) complexes with 2-hydroxybenzaldehyde-4-allyl-S-methylisothiosemicarbazone: Antimicrobial, antioxidant and in vitro antiproliferative activity [Articol]
(2018) Pahonțu, Elena; Usataia, Irina; Graur, Vasilii; Ciumacov, Iurie; Petrenko, Peter; Gudumac, Valentin; Gulea, Aurelian
2-Hydroxybenzaldehyde-4-allyl-S-methylisothiosemicarbazone and Cu (II), Co (III), Fe (III) and Cr (III) complexes were synthesized and characterized. The new obtained compounds were investigated by elemental analysis, magnetic susceptibility measurements, molar electric conductivity, IR, 1H NMR, 13C NMR, UV–Vis spectroscopy. In addition, the structure of the ligand and six complexes has been determined by single-crystal X-ray diffraction analysis. The Cu atom in complex 3 is penta-coordinated in a distorted square–pyramidal coordination geometry, while the metals in complexes 5–9 are in a distorted octahedral environment. For all compounds the antimicrobial activity was studied on a series of standard strains, such as Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Salmonella abony and Candida albicans. The in vitro antiproliferative activity of the ligand and complexes was screened on human leukemia HL-60 cells, human cervical epithelial HeLa cells, human epithelial pancreatic adenocarcinoma BxPC-3 cells, human muscle rhabdomyosarcoma spindle and large multinucleated RD cells. The primary screening on a wider series of cancer cells showed that copper coordination compound 2 manifests high activity towards HeLa, BxPC-3 and RD cancer cells, which is three–six times higher than the activity of doxorubicin. The selectivity index that is the ratio between the IC50 value for the normal MDCK cells and IC50 values for the cancer cells varies in the range 2.44–21.17. This index is 5.5–11 times higher for the copper coordination compound 2 than for the doxorubicin. Cr (III), Fe (III) and Co (III) coordination compounds 6–9 manifest high antioxidant activity towards ABTS•+ that exceeds 47–67 times the activity of Trolox.
Synthesis, Structure and Biological Activity of Coordination Compounds of Copper, Nickel, Cobalt, and Iron with Ethyl N'-(2-Hydroxybenzylidene)-N-prop-2-en-1-ylcarbamohydrazonothioate [Articol]
(2020) Gulea, Aurelian; Usataia, Irina; Graur, Vasilii; Ciumacov, Iurie; Petrenko, Peter; Balan, Greta; Burduniuc, Olga; Țapcov, Victor; Rudic, Valeriu
N-(Prop-2-en-1-yl)hydrazonocarbothioamide reacts with iodoethane in methanol with further addition of 2-hydroxybenzaldehyde to form hydroiodide of carbamohydrazonothioate (HL·HI). The coordination compounds were obtained by interaction of HL or HL·HI with copper, nickel, cobalt and iron salts CuLХ·nH2O [X = Cl–, Br–, NO3–; n = 0–1], Ni(L)2·HI·CH3OH, Сo(L)2X [X = I–, NO3–] and Fe(L)2NO3. The structures of three complexes were established by single crystal X-ray analysis. The synthesized complexes exhibit selective antimicrobial and antifungal activity against a series of standard microorganisms and fungi in the concentration range of 30–500 μg/mL. In addition, nickel and iron complexes selectively inhibit the growth and proliferation of cancer cells and do not adversely affect normal cells.