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

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Author: search.filters.author.Garbuz, OlgaEnd date: 2022

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    Synthesis, Structure, and Biological Activity of Mixed-Ligand Amine-Containing Copper(II) Coordination Compounds with 2-(2-Hydroxybenzylidene)-N-(prop-2-en-1-yl)hydrazinecarbothioamide [Articol]
    (2021) Gulea, Aurelian; Graur, Vasilii; Ulchina, Ianina; Bouroș, Pavlina; Smaglii, Vadim; Garbuz, Olga; Țapcov, Victor
    Сopper(II) nitrate reacts in ethanol with 2-(2-hydroxybenzylidene)-N-(prop-2-en-1-yl)hydrazinecarbothioamide H2L in an 1 : 1 molar ratio to form the coordination compound Cu(HL)NO3·H2O. The introduction of amines [imidazole (Im), 3,5-dibromopyridine (3,5-Br2Py), and 4-methylpyridine (4-Pic)] into the reaction mixture in a molar ratio 1 : 1 : 2 leads to the formation of CuA(HL)NO3·nH2O [A = Im, 3,5-Br2Py, 4-Pic; n = 0, 3] complexes. The structure of the obtained compounds was determined by X-ray structural analysis. The synthesized complexes exhibit antimicrobial, antifungal, antioxidant, and anticancer activities.
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    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.
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    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.
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    Sinteza combinațiilor coordinative noi ale unor metale 3d în baza N(4)-(acetat de etil) tiosemicarbazonelor 2-formil și 2-acetil piridinei. Proprietăți antioxidante [Articol]
    (2022) Rusnac, Anna; Garbuz, Olga; Șova, Sergiu; Gulea, Aurelian
    The given work includes the description of methods for the synthesis of new coordinative combinations of Cu(II), Mn(II), Fe(III) Co(III), Ni(II) and Zn(II) with N(4)-(ethyl acetate) thiosemicarbazones of 2-formylpyridine and 2-acetylpyridine. The characterization of the newly synthesized compounds was carried out using 1H NMR, 13C NMR, FTIR spectroscopy, conductivity, and elemental analysis. In addition, the structures of N(4)-(ethyl acetate) thiosemicarbazide and N(4)-(ethyl acetate) thiosemicarbazone 2-acetylpyridine (HL2) were determined using single crystal X-ray diffraction. The antioxidant activity of coordinative combinations was studied and compared with that of free ligands. The most pronounced antioxidant properties are possessed by [Ni(L2)Cl], whose value of IC50=15,05 μM is three times higher than the IC50=46,76 μM of the non-coordinating ligand and about 2,5 times higher than the reference substances Rutin and Trolox.
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    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, Aurelian
    A 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.
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    Metodă nouă de apreciere a toxicităţii substanţelor chimice [Articol]
    (Imprimt Plus, 2018-09-21) Toderaș, Ion; Gulea, Aurelian; Gudumac, Valentin; Roșcov, Elena; Garbuz, Olga
    We developed a new invention that relates to method for assessing the toxicity of chemical substances.The method of the invention includes the preparation of the culture of Paramecium caudatum, adding to the samples investigated to test chemicals in various concentrations, incubating the sample to be studied and control the addition of colourant 3-amino-7-dimethylamino-2-methylphenazine hydrochloride, incubation with subsequent addition of solution of formalin, centrifuging the sample, removing the supernatant, adding the solution of hydroxide of sodium, determine the absorbance using a spectrophotometer, followed by calculating the percentage of paramecii viability and determine the lethal concentration (LC50) at the same time as the value of the concentration LC50 is small, the toxicity of the tested substance is higher.
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    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.
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    Evaluation of the action of some coordination compounds on infusoria Paramecium caudatum (Ehrenberg, 1833) viability [Articol]
    (2021) Roșcov, Elena; Toderaș, Ion; Gulea, Aurelian; Floquet, Sebastien; Fuior, Arcadie; Garbuz, Olga
    Articolul oferă noi perspective asupra activității biologice a sărurilor de sodiu și litiu ale complexului binuclear [Mo2O4(EDTA)]2- – un model molecular sintetic binecunoscut al centrului activ al molibdoenzimelor. Experiențele clasice cu ciliatul standard Paramecium caudatum (Ehrenberg, 1833) demonstrează un efect stimulator neașteptat asupra viabilității acestora, crescând semnificativ rata lor de reproducere la concentrații micromolare ale sării de litiu în mediul nutritiv.
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    Synthesis of Highly Functionalized Biologically Active Tetracyclic Diterpenoids from ent-Kaur-16-en-19-oic Acid under Modified Prévost-Woodward Reaction Conditions [Articol]
    (2021) Morărescu, Olga; Grinco, Marina; Kulcițki, Veaceslav; Barba, Alic; Garbuz, Olga; Gulea, Aurelian; Ungur, Nikon
    A procedure has been developed for the synthesis of highly functionalized tetracyclic diterpenoids from natural ent-kaur-16-en-19-oic acid under modified Prévost–Woodward reaction conditions. The reaction follows an unusual pathway which leads mainly to bromination or rearrangement products. The transforma­tion of ent-kaur-16-en-19-oic acid afforded a mixture of (16ZE)-17-bromo-ent-kaur-16-en-19-oic, (15R,16E)-17-bromo-15-acetoxy-ent-kaur-16-en-19-oic, (16S)-17-bromo-16-acetoxy-ent-kaur-19-oic, (15S)-15-acetoxy-ent-kaur-16-en-19-oic, and (15S)-15-hydroxy-ent-kaur-16-en-19-oic acids, the latter two being reported previously. The newly syn­thesized compounds were evaluated for their cytotoxicity against two cancer cell lines, HeLa and BxPC-3.
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    The Antiproliferative, Antioxidant Activities and Toxicity of Mixed-Ligand Amine-Containing Copper (II) Coordination Compounds with 2-(2-Hydroxybenzylidene)-N-(Prop-2-En-1-Yl) Hydrazinecarbothioamide [Articol]
    (2021-09-16) Garbuz, Olga; Toderaș, Ion; Ulchina, Ianina; Graur, Vasile; Railean, Nadejda; Gulea, Aurelian
    Five compounds 2-(2-Hydroxybenzylidene)-N-(prop-2-en1-yl)hydrazinecarbothioamide (H2L), bis[μ2-2-({2-[(prop-2-en-1-yl) carbamothioyl] hydrazinylidene}methyl) phenolatoS,N,O:O] diaquadicopper (II) nitrate (1), bis [μ2-2-({2-[(prop-2-en-1-yl) carbamothioyl] hydrazinylidene}methyl)phenolato-S,N,O:O]d iimidazoldicopper(II) nitrate (2), bis[μ2-2-({2-[(prop-2en-1-yl)carbamothioyl]-hydrazinylidene}methyl)phenolato-S,N,O:O]bis-(3,5-dibromopyridine)dicopper( II) nitrate hexahydrate (3), bis[μ2-2-({2-[(prop-2-en-1-yl)carbamothioyl]-hydrazinylidene}methyl) phenolato-S,N,O:O]bis(4-methylpyridine)dicopper(II) nitrate hexahydrate (4) were synthesized. The antiproliferative properties of these compounds towards cancer cell lines HeLa, RD and normal cell line MDCK have been investigated. The tested compounds demonstrated high antioxidant and antiproliferative, selective activities towards cancer cells. Direct toxic evaluation of compounds was performed by Daphnia magna bioassay.