Facultatea de Chimie şi Tehnologie Chimică / Faculty of Chemistry and Chemical Technology

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    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, Victor
    o-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.
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    Synthesis, Structure, and Biological Activity of Copper(II), Nickel(II), Cobalt(III), and Iron(III) Coordination Compounds with 2-{2-[(Prop-2-en-1-yl)carbamothioyl]hydrazinylidene}propanoic Acid [Articol]
    (2020) Gulea, Aurelian; Graur, Vasilii; Diurici, E.; Ulchina, Ianina; Bouroș, Pavlina; Balan, Greta; Burduniuc, Olga; Țapcov, Victor; Rudic, Valeriu
    2-Oxopropanoic acid reacts in ethanol with N-(prop-2-en-1-yl)hydrazinecarbothioamide in a 1 : 1 mole ratio to form thiosemicarbazone H2L. Coordination compounds Cu(HL)X [X = Cl–, Br–, NO3–], Cu(H2O)(L), Ni(HL)2, Co(HL)2X [X = Cl–, Br–], and Fe(HL)2X [X = NO3–, Br–] are formed in the reactions of H2L with copper(II), nickel(II), cobalt(II), and iron(III) salts. The reactions of Cu(H2O)(L) with imidazole (Im) and 3,4-dimethylpyridine (3,4-Lut) result in mixed-ligand complexes Cu(A)(L) [A = Im, 3,4-Lut]. The structures of two copper complexes were determined by single crystal X-ray diffraction analysis. The synthesized complexes exhibit selective antimicrobial and antifungal activity in the concentration range of 15.62–1000 μg/mL. The introduction of amines into the inner sphere of copper complexes leads to an increase in the antimicrobial activity.
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    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.
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    Synthesis, Structure, and Biological Activity of Copper and Cobalt Coordination Compounds with Substituted 2-(2-Hydroxybenzylidene)-N-(prop-2-en-1-yl) hydrazinecarbothioamides [Articol]
    (2019) Gulea, Aurelian; Graur, Vasilii; Ciumacov, Iurie; Petrenko, Peter A.; Balan, Greta; Burduniuc, Olga; Țapcov, Victor; Rudic, Valeriu
    The reaction of N-(prop-2-en-1-yl)hydrazinecarbothioamide with substituted 2-hydroxybenzaldehydes afforded the corresponding Schiff bases which were used as ligands to obtain copper and cobalt coordination compounds Cu(NL1–6)X · n H2O (X = Cl−, NO3−; n = 0–3), Co(HL2)2NO3, and Co(NL6)2Cl. The structure of the isolated complexes was determined by NMR spectroscopy and X-ray analysis. The complexes were tested for antimicrobial and antifungal activity against S. aureus, E. coli, and yeast-like fungi. Inhibitory effect of the initial thioamides and their complexes against human myeloid leukemia HL-60 cancer cell line was also studied.
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    Micromolecular inhibitors of superoxide radicals [Articol]
    (2021) Andronache, Lilia; Pantea, Valeriana; Gulea, Aurelian; Șveț, Inna; Graur, Vasilii; Matcovschi, Valerii; Gamaniuc, Marina; Gudumac, Valentin
    Background: Currently, there is a growing interest in new copper (Cu2+) heterocyclic coordination compounds (CC), isothiosemicarbazide derivates, which demonstrated multiple beneficial properties, but their effect on reactions with free radicals such as the superoxide radical has not been investigated. Material and methods: The action of new micromolecular complexes of copper (Cu2+) chloride and bromide with methyl n- (prop-2-en-1-yl) -2- (pyridin2-ylmethylidene) hydrazine carbimidothioate on capturing activity of the superoxide radical was determined by the spectrophotometric method in vitro experiments. Results: It was established that the micromolecular complexes of copper (II) chloride and bromide with methyl n-(prop-2-en-1-yl)-2-(pyridin-2ylmethylidene) hydrazine carbimidothioate have been found to possess strong superoxide radical inhibitor properties when interacting with a superoxide radical. In addition to this, the IC50 of the studied compounds depends on the nature of the acid-ligand in the internal sphere of the complex and increases in the following sequence: Cl-–Br-. Conclusions: The established property of mentioned compounds is new, because their use as micromolecular inhibitors of superoxide radicals has not been described so far. The synthesized CC expand the arsenal of superoxide radical inhibitors with high biological activity. Their possible significance for the development of new treatment strategies for diseases associated with the overproduction of superoxide radicals is discussed.
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    Coordination compound as inhibitor of superoxid radical [Articol]
    (2019) Garbuz, Olga; Pantea, Valeria; Usataia, Irina; Graur, Vasilii; Țapcov, Victor; Sardari, Veronica; Tagadiuc, Olga; Gudumac, Valentin; Gulea, Aurelian
    A fost obținut un nou compus coordinativ biologic activ, nitratul de cupru [2 - ({2 [(ethylsulfanyl) (prop-2-en-1-yl) carbononoimidooyl] -hydrazinylidene} methyl) phenolate], care face parte din clasa isotiosemicarbazidelor metalelor de tranziție.S-a stabilit că acesta exercită proprietăți anti radicalice performante la acțiunea moleculei organice cu radicalul superoxidic. Datorită acestei poroprietăți compusul obținut poate avea o potențială aplicare in medicină in calitate de inhibitor al radicalilor superoxidici in corpul uman, care poate duce la prevenirea deteriorării tesutului cellular, aterosclerozii si carcinogenezei.Compusul coordinativ sintetizat extinde arsenalul inhibitorilor de radicali superoxidici cu activitate biologică importanta.
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    Coordination chemistry in the Republic of Moldova [Articol]
    (2009) Bulhac, Ion; Gulea, Aurelian; Batâr, Dumitru
    This article is dedicated to the history of apparition and development of Coordination chemistry in Moldova. The main scientific centres are characterized, as well as their main research directions. The most valuable results in fundamental and applicative research are described, obtained in the field of coordination chemistry in the republic.
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    Synthesis, Structure, and Biological Activity of Copper(II), Nickel(II), Cobalt(III), and Iron(III) Coordination Compounds with 2-{2-[(Prop-2-en-1-yl) carbamothioyl] hydrazinylidene} propanoic Acid [Articol]
    (2020) Gulea, А. P.; Graur, V. О.; Diuricia, E. C.; Ulchina, Ia. I.; Bourosh, P. N.; Balanc, G. G.; Burduniuc, O. S.; Tsapkov, V. I.; Rudic, V. F.
    2-Oxopropanoic acid reacts in ethanol with N-(prop-2-en-1-yl)hydrazinecarbothioamide in a 1 : 1 mole ratio to form thiosemicarbazone H2L. Coordination compounds Cu(HL)X [X = Cl–, Br–, NO 3 –], Cu(H 2O)(L), Ni(HL)2, Co(HL)2X [X = Cl–, Br–], and Fe(HL)2X [X = NO3 – , Br–] are formed in the reactions of H2L with copper(II), nickel(II), cobalt(II), and iron(III) salts. The reactions of Cu(H2O)(L) with imidazole (Im) and 3,4-dimethylpyridine (3,4-Lut) result in mixed-ligand complexes Cu(A)(L) [A = Im, 3,4-Lut]. The structures of two copper complexes were determined by single crystal X-ray diffraction analysis. The synthesized complexes exhibit selective antimi- crobial and antifungal activity in the concentration range of 15.62–1000 μg/mL. The introduction of amines into the inner sphere of copper complexes leads to an increase in the antimicrobial activity.
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    Sinteza combinațiilor coordinative ale cuprului(II) și nichelului(II) în baza N(4)-(p-benzoat de etil) tiosemicarbazonelor 5-Br (3,5-di Br) salicilaldehidei [Articol]
    (CEP USM, 2021) Rusnac, Anna
    This article aims to synthesize 2 new organic substances N(4)-(p-ethyl-4-benzoate) thiosemicarbazone 5-Br (3,5-diBr) salicylaldehyde. Based on them, 15 coordination compounds of Cu (II) and Ni (II) were obtained. The organic compound was analysed by IR spectroscopy and characterized by 1H and 13C nuclear magnetic resonance (NMR). The coordination compounds were chemically characterized by elemental analysis and IR spectroscopy. On the basis of IR spectroscopy and elemental analysis showed that the ligands were coordinated to the metal tridentate ligands the sulfur-thionic atom, the azomethine nitrogen atom and the oxygen-phenolic atom. After recrystallization {Ni(HL1)NO3}·2H2O in a 1:3 binary solvent mixtures of N,N-dimethylformamide, ethanol. Single crystals have been obtained, and established the structure by X-ray analysis. Where the ligand is double deprotonated, due to the DMF which possesses basic properties and has favored its double deprotonation, coordinates to the central atom through the sulf-thionic atoms, azomethine nitrogen, oxygen-phenolic, the fourth position is occupied by oxygen from the DMF solvent molecule. The compound formed has a plane square geometry, in the outer sphere coordination compound: is a DMF, co-crystallization molecule.
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    Synthesis and antimicrobial activity of coordination compounds of copper with substituted salicylaldehyde thiosemicarbazones [Articol]
    (Springer, 2005) Prisakar, V. I.; Tsapkov, V. I.; Buracheeva, S.A.; Byrke, M.S.; Gulya, A. P.
    New coordination compounds of copper(II) with thiosemicarbazones of 5-chloro-, 5-bromo-, 5-nitro-, 5-methyl-, 3,5-dichloro-, and 3,5-dibromo-substituted salicylaldehyde have been synthesized and tested with respect to eight strains of staphyloccoccus, streptococcus, and colon bacillus. These compounds exhibit high antimicrobial activity. The composition and structure of the synthesized complexes have been studied by means of elemental analysis and by magnetochemical, IR, and thermogravimetric techniques. The antimicrobial activity of the obtained coordination compounds depends both on the nature of substituents in the benzene ring of salicylaldehyde and on the nature of acid ligands. The maximum antimicrobial activity was observed for copper(II) complexes with thiosemicarbazone of 3,5-dibromsalicyladehyde.