2. Articole
Permanent URI for this collectionhttps://msuir.usm.md/handle/123456789/46
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Item Coordination compounds of cobalt, nickel, copper, and zinc with N 1,N 2-bis (pyridin-2-ylmethylidene)benzene-1,2-diamine and its derivatives [Articol](2014) Pahonțu, Elena; Gulea, Aurelian; Poirier, Donald; Țapcov, Victoro-Phenylenediamine reacts with 2-formyl-, 2-acetyl-, or 2-benzoylpyridine in ethanol in the presence of cobalt, nickel, copper, or zinc chlorides to form monomeric complexes ML1-3Cl2·nH2O {M = Co, Ni, Cu, Zn; L1 = N 1,N 2-bis(pyridin-2-ymethylidene)benzene-1,2-diamine, L2 = N 1,N 2-bis(pyridin-2-ylethylidene) benzene-1,2-diamine, L3 = N 1,N 2-bis[phenyl(pyridin-2-yl)methylidene]benzene-1,2-diamine; n = 0-3}. The condensation products (L1-L3) act in the complexes as tetradentate N,N,N,N-ligands. Thermolysis of the complexes occurs in two stages: dehydration (70-95°C) and complete degradation (320-450°C). At concentrations of 10-5-10-7 M, the complexes inhibit in vitro growth and proliferation of HL-60 human promyelocytic leukemia cells.Item Synthesis, structure, and antimicrobial activity of copper (II) chelates containing imidazole and condensation products of α-amino acids with salicylaldehyde and its derivatives [Articol](2013) Gulea, Aurelian; Lozan-Tîrșu, Carolina; Țapcov, Victor; Ciumacov, Iurie; Janno, E.; Rudic, ValeriuSalicylaldehyde, 5-bromo- and 5-nitrosalicylaldehydes, 2- hydroxynaphthalene-1-carbaldehyde, and 2,3-, 2,4-, and 2,5- dihydroxybenzaldehydes reacted with glycine, alanine, and phenylalanine in ethanol in the presence of imidazole (Im) and copper(II) acetate hydrate to give copper(II) chelates with the composition Cu(Im)(L) · nH2O (H2L is the condensation product of the above aldehydes with α-amino acids; n = 0-2). The structure of the complex Cu(Im)(L 1) [H2L1 = 2-(2-hydroxybenzylideneamino)acetic acid] was determined by X-ray analysis. The crystalline structure of [2-(2-hydroxybenzylideneamino)acetato](imidazole)copper is formed by polymeric chains of the Cu(Im)(L1) molecules linked through bridging oxygen atoms in the carboxy groups of the Schiff base ligand. The coordination unit has a distorted tetragonal pyramid configuration, where the pyramid base is composed of the phenol and carboxy oxygen atoms, CH=N nitrogen atom in the ligand H2L1 and imidazole nitrogen atom. The oxygen atom in the carboxy group in the neighboring molecule occupies the apical position of the coordination pyramid. The other coordination compounds also have polynuclear structure with the Schiff base H2L acting as doubly deprotonated tridentate O,N,O-ligand and bridging carboxy groups. Thermal decomposition of the complexes includes their dehydration (70-95 C), while complete thermal decomposition occurs at 360-530 C. The synthesized complexes showed selective antimicrobial activity in the concentration range from 75 to 300 μg/ml against a number of standard strains of Staphylococcus aureus and Escherichia coli.Item Synthesis, characterization, molecular docking studies and in vitro screening of new metal complexes with Schiff base as antimicrobial and antiproliferative agents [Articol](2019) Paponțu, Elena; Proks, Maria; Șova, Sergiu; Lupașcu, Gina; Ilieș, Diana Carolina; Bărbuceanu, Ștefania Felicia; Socea, Laura Ileana; Badea, Mihaela; Păunescu, Virgil; Istrati, Dorin; Gulea, Aurelian; Drăgănescu, Doina; Dinu Pîrvu, Cristina ElenaA series of Cu(II), Co(II), Pd(II), Pt(II), Zn(II), Cd(II) and Fe(III) complexes were designed and synthesized using Schiff base 1-phenyl-2,3-dimethyl-4-(N-3-formyl-6-methylchromone)-3-pyrazolin-5-one (HL). The new metal complexes were investigated using various physicochemical techniques including elemental and thermal analyses, molar electric conductivity and magnetic susceptibility measurements, as well as spectroscopic methods. Also, the crystal structures of ligand HL and the Pd(II) complex were determined using single-crystal X-ray diffraction analysis. For all compounds, the antimicrobial activity was studied against a series of standard strains: Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, Escherichia coli, Acinetobacter baumannii, Candida albicans, Candida krusei and Cryptococcus neoformans. The in vitro antiproliferative activity of the ligand and complexes was evaluated against ten cancer cell lines: MSC, A375, B16 4A5, HT-29, MCF-7, HEp-2, BxPC-3, RD, MDCK and L20B. At 10 μM concentration a significant cytotoxic effect of the Co(II), Pd(II) and Cd(II) complexes was observed against B16 4A5 murine melanoma cells. The Zn(II) complex is active against HEp-2, RD and MDCK cancer cell lines, where IC50 values vary between 1.0 and 77.6 and for BxPC-3 the activity index versus doxorubicin is 3.7 times higher.Item Synthesis, characterization, crystal structure and antimicrobial activity of copper(II) complexes with the Schiff base derived from 2-hydroxy-4-methoxybenzaldehyde [Articol](2015) Pahonțu, Elena; Ilieș, Diana Carolina; Șova, Sergiu; Paraschivescu, Codruța; Badea, Mihaela; Gulea, Aurelian; Roșu, TudorA novel Schiff base, ethyl 4-[(E)-(2-hydroxy-4-methoxyphenyl)methyleneamino] benzoate (HL), was prepared and structurally characterized on the basis of elemental analyses, 1H NMR, 13C NMR, UV-Vis and IR spectral data. Six new copper(II) complexes, [Cu(L)(NO3)(H2O)2] (1), [Cu(L)2] (2), [Cu(L)(OAc)] (3), [Cu2 (L)2Cl2(H2O)4] (4), [Cu(L)(ClO4)(H2O)] (5) and [Cu2(L2S)(ClO4)(H2O)]ClO4·H2O (6) have been synthesized. The characterization of the newly formed compounds was done by IR, UV-Vis, EPR, FAB mass spectroscopy, elemental and thermal analysis, magnetic susceptibility measurements and molar electric conductivity. The crystal structures of Schiff base and the complex [Cu2(L2S)(ClO4)(H2O)]ClO4·H2O (6) have been determined by single crystal X-ray diffraction studies. Both copper atoms display a distorted octahedral coordination type [O4NS]. This coordination is ensured by three phenol oxygen, two of which being related to the μ-oxo-bridge, the nitrogen atoms of the azomethine group and the sulfur atoms that come from the polydentate ligand. The in vitro antimicrobial activity against Escherichia coli ATCC 25922, Salmonella enteritidis, Staphylococcus aureus ATCC 25923, Enterococcus and Candida albicans strains was studied and compared with that of free ligand. The complexes 1, 2, 5 showed a better antimicrobial activity than the Schiff base against the tested microorganismsItem Synthesis, Structure, and Biologic Activity of Some Copper, Nickel, Cobalt, and Zinc Complexes with 2-Formylpyridine N4-Allylthiosemicarbazone [Articol](2022) Graur, Vasilii; Ciumacov, Iurie; Garbuz, Olga; Hureau, Christelle; Țapcov, Victor; Gulea, AurelianA series of zinc(II) ([Zn(H2O)(L)Cl] (1)), copper (II) ([Cu(L)Cl] (2), [Cu(L)Br] (3), [Cu2(L)2(CH3COO)2]·4H2O (4)), nickel(II) ([Ni(HL)2]Cl2·H2O (5)), and cobalt(III) ([Co(L)2]Cl (6)) complexes were obtained with 2-formylpyridine N4-allylthiosemicarbazone (HL). In addition another two thiosemicarbazones (3-formylpyridine N4-allylthiosemicarbazone (HLa) and 4-formylpyridine N4-allylthiosemicarbazone (HLb)) have been obtained. The synthesized thiosemicarbazones have been studied using 1H and 13C NMR spectroscopy, IR spectroscopy, and X-ray diffraction analysis. The composition and structure of complexes were studied using elemental analysis, IR and UV-Vis spectroscopies, molar conductivity, and magnetic susceptibility measurements. Single crystal X-ray diffraction analysis elucidated the structure of thiosemicarbazones HL, HLa, and HLb, as well as complexes 4 and 5. The antiproliferative properties of these compounds toward a series of cancer cell lines (HL-60, HeLa, BxPC-3, RD) and a normal cell line (MDCK) have been investigated. The nickel complex shows high selectivity (SI > 1000) toward HL-60 cell line and is the least toxic. The zinc complex shows the highest selectivity toward RD cell line (SI = 640). The copper complexes (2-4) are the most active molecular inhibitors of proliferation of cancer cells, but exhibit not such a high selectivity and are significantly more toxic. Zinc and copper complexes manifest high antibacterial activity. It was found that calculated at B3LYP level of theory different reactivity descriptors of studied compounds strongly correlate with their biological activity.Item Expresia enzimelor glutationice în țesutul splenic este influențată de derivații tiosemicarbazidei [Articol](2021) Andronache, Lilia; Pantea, Valeriana; Gulea, Aurelian; Șveț, Ina; Ghindă, Sergiu; Privalova, Elena; Smeșnoi, Valentina; Gudumac, ValentinAdministrarea unor baze heterociclice Schiff noi și complexelor lor cu cuprul (II), derivați ai tiosemicarbazidei induce influenţe variate asupra activității enzimelor glutation-dependente în țesutul splenic. Este evidentă acţiunea selectivă a compușilor studiați asupra expresării enzimelor glutationice care se manifestă prin tendinţă de diminuare nesemnificativă a glutationreductazei (GR) și glutationperoxidazei (GPO), creșterea neimportantă a glutation-S-transferazei (GST) și depresia marcată a nivelului glutaredoxinei. Sporul leger al GST la acțiunea compușilor studiați poate fi considerată drept o reacție de protecție orientată să stagneze intensitatea proceselor peroxidice și să susțină activitatea ciclului glutationic, iar diminuarea enzimoactivității glutaredoxinei denotă efectul lor antiproliferativ, citostatic. Sunt necesare studii suplimentare pentru a evalua mecanismele de acțiune ale compușilor cercetați asupra activității enzimelor glutation-dependente în alte biosisteme și experimente pe animale pentru a aprecia importanța practică a rezultatelor obținute.Item Sinteza dirijată a bazelor Schiff care conţin hidrazinobenzotiazol, 4-aminotriazol, lizină şi compuşii lor coordinativi [Articol](CEP USM, 2016) Paholniţcaia, AnastasiaLucrarea prezintă o revistă a bazelor Schiff care conţin hidrazinobenzotiazol, 4-aminotriazol, lizină şi compuşii coordinativi cu aceşti liganzi descrise în literatura de specialitate. Compuşii coordinativi ai elementelor 3d cu aceşti liganzi au deferită compoziţie, structură şi proprietăţi. Liganzii şi compuşii coordinativi manifestă activitate antitumorală, antibacteriană, antituberculoasă, antiinflamatoare. Compuşii coordinativi ai cuprului cu aceşti liganzi manifestă activitate antitumorală sporită în comparaţie cu bazele Schiff corespunzătoare.Item Synthesis, characterization, crystal structure and antimicrobial activity of copper(II) complexes with the schiff base derived from 2-hydroxy-4-methoxybenzaldehyde [Articol](Molecular Diversity Preservation International (MDPI), 2015) Pahonțu, Elena; Ilieș, Diana-Carolina; Shova, Sergiu; Paraschivescu, Codruța; Badea, Mihaela; Gulea, Aurelian; Roșu, TudorA novel Schiff base, ethyl 4-[(E)-(2-hydroxy-4-methoxyphenyl)methylene-amino]benzoate (HL), was prepared and structurally characterized on the basis of elemental analyses, 1H NMR, 13C NMR, UV-Vis and IR spectral data. Six new copper(II) complexes, [Cu(L)(NO3)(H2O)2] (1), [Cu(L)2] (2), [Cu(L)(OAc)] (3), [Cu2 (L)2Cl2(H2O)4] (4), [Cu(L)(ClO4)(H2O)] (5) and [Cu2(L2S)(ClO4)(H2O)]ClO4·H2O (6) have been synthesized. The characterization of the newly formed compounds was done by IR, UV-Vis, EPR, FAB mass spectroscopy, elemental and thermal analysis, magnetic susceptibility measurements and molar electric conductivity. The crystal structures of Schiff base and the complex [Cu2(L2S)(ClO4)(H2O)]ClO4·H2O (6) have been determined by single crystal X-ray diffraction studies. Both copper atoms display a distorted octahedral coordination type [O4NS]. This coordination is ensured by three phenol oxygen, two of which being related to the µ-oxo-bridge, the nitrogen atoms of the azomethine group and the sulfur atoms that come from the polydentate ligand. The in vitro antimicrobial activity against Escherichia coli ATCC 25922, Salmonella enteritidis, Staphylococcus aureus ATCC 25923, Enterococcus and Candida albicans strains was studied and compared with that of free ligand. The complexes 1, 2, 5 showed a better antimicrobial activity than the Schiff base against the tested microorganisms.