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

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Author: search.filters.author.Gulea, Aurelian

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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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    COMPUȘI COORDINATIVI AI FIERULUI(III) CU UNELE TIOSEMICARBAZONE N(4) – SUBSTITUITE ALE DERIVAȚILOR SALICIL ALDEHIDEI ȘI CINAM ALDEHIDEI
    (CEP USM, 2024) Bîrcă, Maria; Rusnac, Roman; Gulea, Aurelian
    In this paper, the purpose of synthesis of Fe(III) coordination compounds with some N(4)-substituted thiosemicarbazones of salicyl aldehyde and cinnam aldehyde derivatives was pursued: which contain as a radical in the N(4) position: tert-butyl, cyclohexyl; allyl, methyl. The structure of thiosemicarbazones HnL1-5 was confirmed by FTIR spectroscopy and TLC analysis, melting point and NMR spectra. Based on the above-mentioned ligands, 5 coordination combinations were obtained, the research of which was carried out with the help of infrared spectroscopy. All synthesized compounds are being researched for their biological properties: antimicrobial and antifungal, as well as antioxidant capacities.
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    USE OF MICROMOLECULAR COPPER COMPLEXES OF THIOSEMICARBAZIDES AS AN ENDOGENOUS CATALASE INDUCER/ACTIVATOR
    (2024) Andronache, Lilia; Pantea, Valeriana; Gulea, Aurelian; Tagadiuc, Olga; Matcovschi, Valerii
    Oxidative stress is a major mechanism in the pathogenesis of many diseases, including severe multifactorial ones. Catalase (CAT), along with superoxide dismutase, is one of the first-line antioxidant defense enzymes. The development of methods/compounds that can increase/induce CAT will provide new possibilities to strengthen antioxidant protection and prevent oxidative damage to cells and tissues.
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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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    SINTEZA ȘI STUDIUL COMPUȘILOR COORDINATIVI HOMO- ȘI HETEROMETALICI AI CU(II) ȘI BI(III) CU 4-ETILTIOSEMICARBAZONELE 2-FORMIL ȘI 2-ACETILPIRIDINEI
    (CEP USM, 2023) Neguța, Elena; Gulea, Aurelian; Cotovaia, Aliona; Bulimestru, Ion; Bălan, Greta; Șova, Sergiu
    În această lucrare sunt prezentate sinteza și studiul a două serii de compuși coordina- tivi homo- și heterometalici ai Cu(II) și Bi(III) cu 4-etiltiosemicarbazonele 2-formil și 2-acetilpiridinei, cu formulele generale: {Cu(HL)}Cu(edta)•nH2O, {Cu(L)}2Cu(edta)•nH2O în cazul complecșilor homometalici ai Cu(II) și {Cu(L)}Bi(edta)•nH2O (n = 1 - 5), pentru compușii heterometalici Cu(II)-Bi(III). În complecșii sintetizați, 4-etiltiosemicarbazonele 2-formilpiridinei (HFoPyTSC-4Et) și 2-acetilpiridinei (HAcPyTSC-4Et) sunt în formă monodeprotonată (L) sau nedeprotonată (HL), iar edta4- reprezintă ionul etilendiamintetracetat. A fost determinată activitatea antimicrobiană și antifungică a compușilor homo- și heterometalici obținuți. Rezultatele au demonstrat că cea mai mare activitate antimicrobiană a manifestat-o compusul [Cu(AcPyTSC-4Et)Bi(edta)]·5H2O, fiind de cca 76 și 19 ori mai activ decât Furacilina (CMI = 4,67 μg/mL) în cazul tulpinilor Staphylococcus aureus (ATCC 25923) și Bacillus cereus (ATCC 11778), respectiv. Iar împotriva tulpinei Candida albicans, cel mai activ agent antifungic a fost compusul {Cu(AcPyTSC-4Et)}2Cu(edta)·H2O, cu CMI = 0,98 μg/mL, care este de cca 32 de ori mai activ decât Nistatina (CMI = 32,0 μg/ mL).
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    SYNTHESIS, COMPUTATIONAL PHARMACOKINETICS REPORT, ADMET STUDY AND MOLECULAR DOCKING OF NEW THIOSEMICARBAZONES POTENTIAL INHIBITORS OF HER2 - POSITIVE BREAST CANCER
    (CEP USM, 2024) Rusnac, Roman; Ciursin, Andrei; Gulea, Aurelian
    To maintain a high level of healthcare, humanity needs to develop new drugs. Thiosemicarbazones represent a very interesting class of substances from the point of view of their biological activities. Despite this, their use is very limited due to their toxicity. To solve this problem, it is possible to synthesize thiosemicarbazones based on natural substances. This can reduce their toxicity without loss of effectiveness. a number of computational methods can be used for the design and preliminary evaluation of thiosemicarbazones, which will help eliminate many unsuitable candidates. This will help reduce the cost and speed up the pace of development of new effective substances from this class. such methods include aDMeT calculations and molecular docking.
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    COMBINAȚII COORDINATIVE ALE CUPRULUI(II) CU ({(2 [(PIRIDIN-2-IL)METILIDEN]HIDRAZINCARBOTIOIL} AMINO) ACETAT DE ETIL CU PROPRIETĂȚI ANTIOXIDATIVE
    (CEP USM, 2024) Bîrcă, Maria; Rusnac, Anna; Garbuz, Olga; Evtodienco, Carolina; Gulea, Aurelian
    In this work, ethyl 2-isothiocyanatoacetate and [(hydrazinecarbotyoyl)amino]ethyl acetate, which are precursors of thiosemicarbazones, were synthesized.Based on these compounds, the synthesis of two new thiosemicarbazones ethyl 2-(2-(pyridin-2-ylmethylene)hydrazinecarbothioamido)acetate (Hl1) and ethyl 2-(2-(1-(pyridin-2-yl)-ethylidene)hydrazinecarbothioamide)acetate (Hl2) with yields between 85-88%. The thiosemicarbazones obtained were confrmed using 1H and 13C-nMR and FTIR spectroscopy. For the frst time, 8 coordination compounds were obtained based on thiosemicarbazone (Hl1 - Hl2) and Cu(II) salts: [Cu(l1)Br], [Cu(l1)(H2O)Cl], [Cu(l1)nO3], [Cu(l1)(H2O)ClO4], [Cu(l2)Br], [Cu(l2)(H2O)Cl], [Cu(l2)nO3], [Cu(l2)(H2O) ClO 4]. The composition of the synthesized coordination compounds was determined by elemental metal analysis and IR spectroscopy.For the synthesized compounds, the antioxidant capacity was evaluated by means of the aBTs method. In which ethyl 2-(2-(pyridin-2-ylmethylene)hydrazinecarbothioamido)acetate (Hl1) and ethyl 2-(2-(1-(pyridin-2-yl)ethylidene)hydrazinecarbothioamido)acetate (Hl2) were shown to exhibit the best results compared to the reference substance Trolox.
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    EFECTUL ANTIBACTERIAN AL UNOR COMPUŞI ORGANICI NOI DIN RÂNDUL SULFANILAMIDELOR
    (2009) Prisacari, Viorel; Buraciova, Svetlana; Țapcov, Victor; Gulea, Aurelian
    Studiul dat se referă la un grup de substanţe sintetice noi din rândul sulfanilamidelor, care manifestă activitate antibacteriană pronunţată faţă de bacteriile grampozitive şi gramnegative şi, totodată, toxicitate joasă.
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    SYNTHESIS,CHARACTERIZATION,ANDBIOLOGICALPROPERTIESOFTHE COPPER(II)COMPLEXESWITHNOVELLIGAND:N-[4-({2-[1-(PYRIDIN2-YL)ETHYLIDENE]HYDRAZINECARBOTHIOYL}AMINO)PHENYL]ACETAMIDE
    (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.
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    COORDINATION COMPOUNDS OF COBALT, NICKEL, COPPER, AND ZINC WITH N1,N2 -BIS(PYRIDIN-2-YLMETHYLIDENE)BENZENE-1,2-DIAMINE AND ITS DERIVATIVES
    (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.