2. Articole

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Author: search.filters.author.Rusnac, AnnaSubject: search.filters.subject.coordination compounds

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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, characterization, antioxidant activity evaluation of 3d metals complexes with N(4)-((3)-ethyl benzoate) thiosemicarbazones of 2-formyl(2-acetyl, 2-benzoil)pyridine [Articol]
    (CEP USM, 2022) Rusnac, Anna; Garbuz, Olga; Shova, Sergiu; Gulea, Aurelian
    The paper presents the synthesis of new coordination compounds of Cu(II), Mn(II), Fe(III) Co(III), Ni(II) and Zn(II) with N(4)-((3)-ethyl benzoate)thiosemicarbazones of 2-formyl pyridine derivatives obtained through the condensation of N(4)-((m)-ethyl benzoate) thiosemicarbazide with 2-pyridinecarboxaldehyde, 2-acetylpyridine and 2-benzoylpyridine. The characterization of new compounds was done by 1H NMR, 13C NMR, IR spectroscopy, conductivity and elemental analysis. In addition, the structures of the ligands (HL1,3) were determined by single-crystal X-ray diffraction. The effect of these complexes on antioxidant activity were studied and compared with those of free ligands. The best result was found to be on coordination compound [Zn(L1)Cl], with IC50 = 11.45 μM, it is better than the free ligand HL1, IC50 = 13.15 μM and is better than the substance Trolox, IC50 = 15.86 μM (it is a pronounced antioxidant taken as a control substance).
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    Sinteza combinațiilor coordinative ale cuprului(II) și nichelului(II) în baza N(4)-(p-benzoat de etil) tiosemicarbazonelor 5-Br (3,5-di Br) salicilaldehidei [Articol]
    (CEP USM, 2021) Rusnac, Anna
    This article aims to synthesize 2 new organic substances N(4)-(p-ethyl-4-benzoate) thiosemicarbazone 5-Br (3,5-diBr) salicylaldehyde. Based on them, 15 coordination compounds of Cu (II) and Ni (II) were obtained. The organic compound was analysed by IR spectroscopy and characterized by 1H and 13C nuclear magnetic resonance (NMR). The coordination compounds were chemically characterized by elemental analysis and IR spectroscopy. On the basis of IR spectroscopy and elemental analysis showed that the ligands were coordinated to the metal tridentate ligands the sulfur-thionic atom, the azomethine nitrogen atom and the oxygen-phenolic atom. After recrystallization {Ni(HL1)NO3}·2H2O in a 1:3 binary solvent mixtures of N,N-dimethylformamide, ethanol. Single crystals have been obtained, and established the structure by X-ray analysis. Where the ligand is double deprotonated, due to the DMF which possesses basic properties and has favored its double deprotonation, coordinates to the central atom through the sulf-thionic atoms, azomethine nitrogen, oxygen-phenolic, the fourth position is occupied by oxygen from the DMF solvent molecule. The compound formed has a plane square geometry, in the outer sphere coordination compound: is a DMF, co-crystallization molecule.
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    Sinteza combinațiilor coordinative cu unele metale 3d în baza N(4)-(4-benzoat de etil) tiosemicarbazone ale derivaților aldehidei salicilice. proprietăți antimicrobiene, antifungice și antioxidative [Articol]
    (CEP USM, 2021) Rusnac, Anna; Țurcanu, Nina; Burduniuc, Olga; Balan, Greta; Garbuz, Olga; Gulea, Aurelian
    În lucrare este descrisă sinteza a 4 substanțe organice noi N(4)-(4-benzoat de etil) tiosemicarbazone ale derivaților aldehidei salicilice și a 29 combinații coordinative ale Cu(II), Ni(II), Zn(II) și Co(III). Structurile substanțelor sintetizate au fost confirmate cu ajutorul spectroscopiei IR și RMN, analizei elementale, magnetochimiei și, în cazul [Ni(L2) DMF]·DMF, difracției cu raze X. Studiul activității antimicrobiene s-a dovedit a fi în limita concentrației 0,125-0,500 mg/mL, iar activitate antifungică a înregistrat cel mai bun rezultat pe Cryptococcus neoformans la complexul {Ni(HL1)Cl}•C2H5OH•3H2O, unde CMI=0,016 mg/mL, fiind mai activ decât substanța martor Nistatina. Cele mai bune rezultate ale testului ABTS au fost înregistrate la ligandul H2L3(7) și la complexul {Ni(HL3) NO3}•H2O (7.8), care la concentrația 100 µM inhibă 54,4% din radicali ABTS•+.
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    Compușii coordinativi ai unor biometale cu liganzii în baza tiosemicarbazonelor ce conțin 4-aminobenzoat de etil [Articol]
    (CEP USM, 2020) Rusnac, Anna
    Lucrarea prezintă studiul literaturii de specialitate în care se iau în atenție sinteza și proprietățile biologice ale unor compuși coordinativi ai metalelor 3d cu liganzii în baza N(4)- aril -tiosemicarbazone. Conform literaturii de specialitate, există doar o tiosemicarbazonă a 2-acetilpiridinei în baza 4-aminobenzoatului de etil. Compușii coordinativi ai metalelor 3d cu N(4)-ariltiosemicarbazone posedă un spectru larg de activități biologice, cum ar fi: antibacteriană, antifungică, antivirală, antimalarială, antitumorală. Compușii coordinativi descriși în prezenta lucrare au o capacitate de inhibiţie sporită la nivel de concentraţii nanomolare (IC50= 0,01-0,001 μM) care întrec de zeci şi sute de ori activitatea antitumorală, spre exemplu, a doxorubicinei.