Browsing by Author "Bulmaga, Petru"

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    COORDINATION PECULIARITIES OF THE SALICYLALDEHYDE S-METHYLISOTHIOSEMICARBAZONE IN THE PALLADIUM COMPLEXES
    (Academia de Ştiinţe a Moldovei, 2006) Revenco, Mihail; Bourosh, Pavlina; Duca, Gheorghe; Simonov, Yurii; Bulmaga, Petru; Jora, Elena; Gdaniec, Maria; Ketrush, Petru
    Two coordination modes of salicylaldehyde S-methylthiosemicarbazone (Me-S-HSATSC-NH2) have been observed in the palladium complexes with this ligand. The interaction between Me-S-HSATSC-NH2 and tetrachloropalladate gives rise to the formation of a compound of the composition Pd(Me-S-SATSC-NH2)Cl which one has a planar structure. The organic ligand behaves as a monodeprotonated acid coordinated by O,N,S donor atoms set. This is the only case when the thioalkylated thiosemicarbazone uses the sulfur atom for coordination. The forth position in the coordination polyhedron of the complex is occupied by the chloride ion.figureMolecular structure of [Pd(Me-S-SATSC-NH2)Cl] and [Pd(Me-S-SATSC-N-NO)NO2]When the solution of K2[Pd(NO2)4] was treated with Me-S-HSATSC-NH2, the organic reagent undergoes a more dramatic chemical transformation carrying out to the formation of a new derivative of thiosemicarbazide – nitrozothioamide Me-S-SATSC-N-NO. The newly synthesized organic reagent is a monodeprotonated acid bound via O,N,N donor set, while the alkylated sulfur atom is uncoordinated. The forth site is occupied by NO2-ion coordinated by nitrogen atom (see fig.). The possible causes, driving the system to the formation of nitrosothioamide, and the impact of the anion on the coordination mode of the organic ligand will be discussed.
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    POLIMERI ANALOGI DIN COPOLIMERI DE N-VINILPIROLIDONĂ GREFAT CU FTALOCIANINĂ DE ZINC
    (CEP USM, 2023) Robu, Ștefan; Potlog, Tamara; Lungu, Ion; Bulmaga, Petru; Tiulenau, Pavel; Prisacari, Viorel; Sava, Veronica
    În lucrare este descrisă sinteza polimerilor analogi din N-vinilpirolidonă cu clorură de acriloil funcționalizați cu ftalocianină de zinc utilizând metoda Friedel-Crafts. Grefarea ftalocianinei de zinc la copolimerul de N-vinilpirolidonă s-a realizat la temperaturi joase (3-5 ⁰C), cu utilizarea catalizatorului AlCl3 anhidru. Purificarea polimerilor noi s-a realizat prin precipitarea în apă. Analiza structurii chimice a polimer analogilor s-a realizat prin utilizarea spectroscopiei IR și UV/Vis. A fost evaluată activitatea antimicrobiană, in vitro, a copolimerilor grefați cu ftalocianină de zinc față de tulpinile microbiene ca S. Aureus, E. Coli, Ps. Aeruginosa și altele. S-a demonstrat că polimer analogii obținuți posedă activitate bactericidă relativ înaltă față de culturile Ps. Aeruginosa, Pr. Vulgaris în comparație cu furacilina sau clorhexidina, utilizate în calitate de substanțe de referință.
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    SINTEZA ŞI CERCETAREA UNOR COPOLIMERI DIN N-VINILCARBAZOL CU ALCHENE SUPERIOARE
    (CEP USM, 2008) Robu, Ştefan; Mitcov, Dmitri; Bulmaga, Petru; Dragalina, Galina; Barbă, Nicanor
    The synthesis and investigations of binary N-vinylcarbazole copolymers with higher alkenes and ternary N-vinylcarbazole copolymers with oct-1-ene, hexadec-1-ene and vinylacetate are presented in this paper. The structure of synthesized copolymers was determined using IR and 1H NMR spectroscopies and elemental analysis. Copolymerization constants were determined using UV spectroscopy. The results of copolymer thin films, sensitized with iodoform, cross-linking after UV and laser ( λ = 0,42 μm) irradiation are presented. It was determined that thin films deposited from these copolymers cross-link 1,5–2,0 times faster than other carbazole containing copolymers known in literature. In coherent He-Cd (λ = 0,42 μm) laser light were recorded high quality holograms, that allow to recommend these fotorezistive materials as optical information recording media.
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    SINTEZA ȘI CERCETAREA FTALOCIANINELOR DE ZN SUBSTITUITE CU GRUPĂRI NITRO ȘI AMINO
    (CEP USM, 2022-11-10) Popuşoi, Ana; Lungu, Ion; Rusnac, Roman; Bulmaga, Petru; Robu, Ştefan; Potlog, Tamara
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    SINTEZA ȘI CERCETAREA UNOR COPOLIMERI DIN CHITOSAN GREFAȚI CU FTALOCIANINĂ DE ZINC, PENTRU SCOPURI MEDICINALE
    (CEP USM, 2024) Popușoi, Ana; Potlog, Tamara; Bulmaga, Petru; Sadohina, Olga; Robu, Ștefan
    In the present work, we describe new copolymers of chitosan grafted with zinc aminomethylphthalocyanine, which was obtained through the mono-(o-carboxybenzamidomethyl) hydrolysis of zinc phthalocyanine at a temperature of 170-175 ℃. Copolymers of aminomethylphthalocyanine with mass contents of 10%, 20%, and 30% of H2nCH2-PCZn were successfully synthesized, and they exhibited good solubility in water and other organic solvents. The chemical structure of the copolymers was proposed through infrared molecular absorption spectroscopy. according to their optical properties in the uV-VIs region, these water-soluble copolymers can be utilized in photodynamic therapy.
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    SPECTROSCOPIC PROPERTIES OF ZnPc(COOH)4/Ch/Fe3O4 SUPRAMOLECULAR ARCHITECTURES
    (CEP USM, 2024) Druță, Alexandrina; Lungu, Ion; Popușoi, Ana; Potlog, Tamara; Bulmaga, Petru; Rusnac, Roman
    This paper presents the synthesis of ZnPc(COOH)4/Ch/Fe3O4 supramolecular architectures at various ZnPc(COOH)4 and Ch/Fe3O4 concentrations explored in the synthesis process. Ch/Fe3O4 composite was prepared by a simple solution mixing-evaporation method. The validation of the synthesis was achieved through FTIR analysis and UV-Vis spectroscopy. FTIR of composite indicated an interaction between chitosan and Fe3O4 NPs. The chemical interaction of ZnPc(COOH)4 with Ch/F3O4 composite is confirmed by the shift of the signal from ν(C=O)) of protonated COOH groups in the FTIR spectrum of ZnPc(COOH)4, associated with spitting, to (νsym(COO)) and (νasym(COO)) that correspond to deprotonated carboxylic group. The absorption spectra of ZnPc(COOH)₄ revealed IR Q band with two subbands situated at 640 nm 700 nm. Also, the effect of various ZnPc(COOH) and Ch/Fe3O4 concentrations on absorbance of ZnPc(COOH)4/Ch/Fe3O4 supramolecular architecture is discussed.
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    STRUCTURE OF PALLADIUM COMPLEXES WITH 8-QUINOLINEALDEHYDE THIOSEMICARBAZONE
    (Academia de Ştiinţe a Moldovei, 2006) Bourosh, Pavlina; Bulmaga, Petru; Revenco, Mihail; Jora, Elena; Gdaniec, Maria; Simonov, Yurii A.
    The coordination compounds of palladium(II) with 8-quinolinaldehyde thiosemicarbazone (HQATSC) have not been described yet. When a solution of K2[PdCl4] is treated with an equimolar amount of HQATSC in warm ethanol or dimethylformamide a yellow crystalline precipitate of Pd(QATSC)Cl is formed. The solubility of the resulted compound in DMF is increased when thiourea (Thio) is added. During 3 days yellow well defined crystals were formed and selected for X-ray investigation. The composition of the separated crystals can be described with a conventional formula Pd(QATSC)Cl⋅1,5Thio⋅H2O. A detailed X-ray investigation showed that the product is a new type of palladium complexes with HQATSC, formed by the cation [Pd(QATSC)(Thio)]+, Cl- anion, water and thiourea uncoordinated molecules. This result suggests that increasing of the ion solubility in the presence of Thio is due to the substitution of the chloride-ion from the inner sphere by thiourea molecule, resulting in formation of a cation-anion type of the complex. The structure of the complex cation is presented in the figure. The square-planar coordination of Pd(II) is provided by two nitrogen atoms and sulfur atom of the monodeprotonated residue of 8-quinolinealdehyde thiosemicarbazone. The bond distances in the palladium coordination polyhedron are: Pd(1)N(1) 2.116(4), Pd(1)-N(2) 2.013(4), Pd(1)-S(1) 2.44(1), PdS(1A) 2.336(1) Å. The real composition of the complex is [Pd(Q ATSC)(Thio)]Cl.0,5Thio.0.5H2O. The non-coordinated Thio and H2O molecules are randomly disordered over two positions with occupancy factors equal to 0.5. The components are involved into system of hydrogen bonds, and the composition should be formally described by the dimeric formula [Pd(QATSC)(Thio)]2Cl2 .Thio.H2O.
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    STRUCTURE OF PALLADIUM COMPLEXES WITH TRIDENTATE THIOSEMICARBAZONES
    (Academia de Ştiinţe a Moldovei, 2012) Bulmaga, Petru; Bourosh, Pavlina; Jora, Elena; Revenco Mihail; Lipkowski, Janusz; Wicher, B.; Palamarciuc, Oleg
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    SYNTHESIS, STRUCTURE AND SPECTROPHOTOMETRIC PROPERTIES OF PALLADIUM(II) 8-QUINOLINALDEHYDE N(4)-(2,4,6)- TRIMETHYLPHENYLTHIOSEMICARBAZONE
    (Academia de Ştiinţe a Moldovei, 2015) Bulmaga, Petru; Bourosh, Pavlina; Sirbu, Ana; Corja, Ion; Cazac, Tatiana