2. Articole

Permanent URI for this collectionhttps://msuir.usm.md/handle/123456789/46

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Author: search.filters.author.Graur, Vasilii

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    Synthesis and biological activity of n-(4-methoxyphenyl)-2-oxopropanamide 4-phenylthiosemicarbazone and its copper(II) complexes
    (CEP USM, 2024) Graur, Ianina; Usataia, Irina; Graur, Vasilii; Tsapkov, Victor; Gulea, Aurelian; Garbuz, Olga; Balan, Greta
    The new N-(4-methoxyphenyl)-2-oxopropanamide 4-phenylthiosemicarbazone (HL) and its 5 copper(II) coordination compounds [Cu(L)X] (X = Cl- (I); Br- (II); NO3- (III); CH3COO- (IV); Cl2CHCOO- (V)) have been synthesized and characterized by elemental analysis, FTIR and NMR spectra. Coordination of 4-phenylthiosemicarbazone HL with the copper(II) atom led to increased antibacterial activity against Staphylococcus aureus and Bacillus cereus. Non-coordinated 4-phenylthiosemicarbazone (HL) showed the highest activity in relation to ABTS•+ cation radicals; its activity is close to that of Trolox, which is used in medicine. The antibacterial and antioxidant activities of the synthesized complexes are influenced by the nature of the acidic residue in their composition.
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    Exploring the antioxidant activity of 1-(piperidin-1-yl) propane-1,2-dione 4-phenylthiosemicarbazone and 3d metal coordination compounds with this ligand
    (CEP USM, 2024) Graur, Ianina; Maxim, Mihail; Graur, Vasilii; Tsapkov, Victor; Gulea, Aurelian; Garbuz, Olga
    The new 1-(piperidin-1-yl)propane-1,2-dione 4-phenylthiosemicarbazone (HL) and its 7 coordination compounds [Cu(L)X] (X = Br- (I); Cl- (II); NO3 - (III); CH3COO- (IV); Cl2CHCOO- (V)), [Co(L)2]NO3 (VI), [Fe(L)2]NO3 (VII) have been synthesized and characterized by elemental analysis, FTIR, 1H, 13C NMR spectra and molar electric conductibility. For the obtained compounds it was studied the antioxidant activity towards ABTS•+ radical cation. Uncoordinated 4-phenylthiosemicarbazone HL is the most active one with IC50 14.1 μM. Its activity is higher than that of Trolox which is used in medicine as an antioxidant. Among all the synthesized coordination compounds, the iron(III) complex VII showed the greatest activity. The antioxidant activity of metal complexes is influenced by the anion and the nature of the central metal atom.
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    Synthesis of 2-formylpyridine 4-allylselenosemicarbazone
    (Institutul de Chimie, AȘM, 2014-05-28) Graur, Vasilii
    From the literature source it is known that in many cases enhancement of biological activity is observed when going from semicarbazones/thiosemicarbazones to the corresponding selenosemicarbazones. Many selenosemicarbazones possess antimicrobial, antimalarial, and antitumor activity. Therefore, the aim of this work is finding the synthesis conditions, determination of the composition and structure of 2-formylpyridine 4-allylselenosemicarbazone.
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    COORDINATION COMPOUNDS OF COPPER(II) WITH SUBSTITUTED 3-{[(2-HYDROXYPHENYL)METHYLIDENE]AMINO}PROPANE-1,2-DIOLS
    (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).
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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)HYDRAZINE- CARBOTHIOAMIDE
    (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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    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
    (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
    (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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    NICKEL(II) COMPLEXES WITH PENTANE-2,4-DIONE BIS(4-ALLYLTHIOSEMICARBAZONE)
    (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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    SYNTHESIS, STRUCTURE, AND BIOLOGICAL ACTIVITY OF COPPER AND COBALT COORDINATION COMPOUNDS WITH SUBSTITUTED 2-(2-HYDROXYBENZYLIDENE)-N-(PROP-2-EN-1-YL)HYDRAZINE- CARBOTHIOAMIDES
    (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.