Facultatea de Chimie şi Tehnologie Chimică / Faculty of Chemistry and Chemical Technology
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Item COORDINATION COMPOUNDS OF COPPER(II) WITH BENZOYLHYDRAZONES OF SUBSTITUTED SALICYLALDEHYDES(2003) Samusi, Nina; Țapcov, Victor; Kerner, A.Benzoylhydrazones of 5-nitro- (H2L1), 3-nitro- (H2L2), 5-chloro- (H2L3), 5-bromo- (H2L4), and 3,5-dibromosalicylaldehydes (H 2L5) react in ethanol with copper acetate to form complexes CuL1-5. In the presence of amines (A = C5H 5N, 3-CH3C5H4N), the above reactions give complexes CuL1-5A·nH2O (n = 0, 1). When cuprous bromide or nitrate and benzoylhydrazone H2L3 were used as starting materials, complexes Cu(HL3)X (X = Br-, NO3-) were isolated. The resulting complexes all are polynuclear structures in which azomethines H2L1-5 behave as tridentate O,N,O-ligands. Thermolysis of the complexes involves the stages of dehydration (70-90°C), deaquation (120-150°C) or deamination (150-180°C), and complete thermal decomposition (350-500°C).Item COORDINATION COMPOUNDS OF COBALT, NICKEL, AND COPPER WITH ISONITROSOACETONE BENZOYLHYDRAZONE(2002) Țapcov, VictorBenzoylhydrazine and isonitrosoacetone react in ethanol with cobalt, nickel, and copper halides and acetates to give the coordination compounds MX2(HL)·nH2O, MX2(HL) 2·nH2O, and ML2·nH2O [M = Co, Ni, Cu; X = Cl, Br; HL = C6H5C(O)NHNC(CH 3)CHNOH; n = 1-4]. The same reactions performed in the presence of sodium acetate and pyridine (pH 7-8) yield the complexes MLCl·nH 2O and MPy2LCl·nH2O (n = 1-4). All the complexes have a pseudooctahedral coordination geometry. The hydrazone HL behaves as a tridentate O,N,N-donor ligand. Thermolysis of the substances involves dehydration (70-90°C), deaquation (155-170°C) or deamination (175-195°C), and complete thermal decomposition (285-360°C).Item UNGUENT „IZOFURAL” - PREPARAT ANTIBACTERIAN NOU.COMUNICARE I. STUDIUL ACTIVITĂŢII ANTIBACTERIENE(2010) Prisacari, Viorel; Buraciova, Svetlana; Uncu, Livia; Vâslouh, Oxana; Țapcov, VictorStudiul dat se referă la un preparat nou “Izofural”, care manifestă activitate antibacteriană pronunţată faţă de bacteriile grampozitive şi gramnegative.Item EFECTUL ANTIBACTERIAN AL UNOR COMPUŞI ORGANICI NOI DIN RÂNDUL SULFANILAMIDELOR(2009) Prisacari, Viorel; Buraciova, Svetlana; Țapcov, Victor; Gulea, AurelianStudiul 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.Item 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, AurelianFor 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.Item 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, 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 COORDINATION COMPOUNDS OF COPPER AND NICKEL WITH N,N'-[4,4'-(PERFLUORO-1,4-PHENYLENE)BIS(OXY)BIS(4,1-PHENYLENE)]- BIS[2-(PYRIDIN-2-YLMETHYLIDENE)HYDRAZINECARBOTHIOAMIDE] AND ITS DERIVATIVES(2014) Pahonțu, Elena; Țapcov, Victor; Poirier, Donald; Gulea, AurelianN,N′-[4,4′-(Perfluoro-1,4-phenylene)bis(oxy)bis(4,1-phenylene)] bis[2-(pyridin-2-ylmethylidene)-hydrazinecarbothioamide] as well as its methyl and phenyl derivatives react with copper and nickel chlorides in ethanol to form coordination compounds. In the products, the hydrazinecarbothioamides act as doubly deprotonated bridging ligands. The prepared complexes have been found to inhibit in vitro the growth and propagation of the myeloid human leukemia HL-60 cancer cells at the 10-5-10-7 mol/L concentration.Item COORDINATION COMPOUNDS OF COPPER(II) WITH SUBSTITUTED 3-{[(2-HYDROXYPHENYL)METHYLIDENE]AMINO}PROPANE-1,2-DIOLS(2013) Gulea, Aurelian; Ciumacov, Iurie; Graur, Vasilii; Țapcov, Victor3-{[(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).Item SYNTHESIS, STRUCTURE, AND ANTIMICROBIAL ACTIVITY OF COPPER(II) CHELATES CONTAINING IMIDAZOLE AND CONDENSATION PRODUCTS OF α-AMINO ACIDS WITH SALICYLALDEHYDE AND ITS DERIVATIVES(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, STRUCTURE AND PROPERTIES OF COMPLEX COMPOUNDS OF COBALT, NICKEL, COPPER AND ZINC WITH 2-FORMYLPYRIDINE SEMICARBAZONE(2009) Gulea, Aurelian; Gînju, Dumitru; Bairac, Natalia; Poirier, Donald; Țapcov, Victor2-Formylpyridine semicarbazone L reacts with cobalt, nickel, copper and zinc chlorides, nitrates and perchlorites to form coordination compounds of compositions ML2X2•nH2O (M=Co, Ni, Cu, Zn; X = Cl, NO3, ClO4; L = NC5H 4-CH=N-NH-C(O)-NH2; n = 0, 1) and CuLX2• nH2O (X = Cl, Br, NO3; n = 0-0.5). Complex CuL(NO 3)2 has polynuclear, CuLX2•0.5H 2O (X = Cl, Br), binuclear, and other compounds, mononuclear structures. Azomethine L behaves in them as tridental N,N,O-ligand. Thermolysis of these complexes proceeds through such stages as dehydration (80-95°C), deactivation (145-155°C) and complete theral degradation (170-590°C). Complexes CuLX2•nH2O (X = Cl, NO3; n = 0-0.5) were established to inhibit in vitro the growth and reproduction of 100% of cancer cells of human mieloid leukaemia HL-60 at 10-4 M concentration. At 10-5 M concentration they inhibit only 10% of cells, and at 10-6 M concentration they do not possess anticancer activity.