Facultatea de Chimie şi Tehnologie Chimică / Faculty of Chemistry and Chemical Technology
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Item ACTIVITATEA ANTIOXIDANTĂ A FILMELOR CU EXTRACTE DIN PRODUSE VEGETALE DE SOPHORA JAPONICA L.(CEP USM, 2024) Grigoraș, Carolina; Ciocârlan, Alexandru; Gonţa, MariaPlant products of S. japonica, more precisely: flowers, fruits and seeds collected in May and September, respectively, have been conditioned, and the products obtained serve as a source of raw material. The extracts were obtained from the vegetable raw material by maceration, distillation and hydrodistillation using various solvents, with the subsequent incorporation into the filmogenic mixture of chitosan:pectin, to obtain polymeric films. The obtained films were evaluated according to quality indices, thus the appearance, smell and mechanical properties were analyzed, the thickness of the films was measured and antioxidant properties were determined. The prepared biomaterials are uniform, thin, elastic, flexible, have no smell and have a specific color of the composition, manifest an antioxidant activity, but this varies depending on the composition of the prepared films.Item 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, GretaThe 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.Item 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, OlgaThe 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.Item POLIFENOLII DIN VINURILE MOLDOVENEȘTI ȘI IMPLICAREA LOR ÎN PROCESE ANTIOXIDANTE ȘI ANTI-STRES(Editura USM, 2023) Druța, Raisa; Duca, Gheorghe; Sturza, Rodica; Covaci, Ecaterina; Subotin, IuriePrezentul studiu analizează proprietățile antioxidante și anti-stres corelate polifenolilor din struguri și vin, precum și impactul lor asupra proceselor oxidative din alimente, care afectează diferite clase de compuși: acizii grași, vitamine, aminoacizi. Sunt detaliate compoziția, activitatea antioxidantă și mecanismele posibile de reacție ale flavonoidelor, flavonolilor, flavonelor, antocianiadinelor. A fost cercetată compoziția polifenolilor individuali și activitatea antioxidantă a vinurilor moldovenești de soiuri autohtone. S-a constatat, că vinurile moldovenești autohtone: roșii - Rară Neagră, Fetească Neagră și albe - Feteasca Albă, Feteasca Regală, Viorica prezintă surse veritabile de compuși bioactivi, cu capacitate antioxidantă importantă. Dintre polifenolii importanți, compușii majoritari determinați în toate probele au fost acidul galic, resveratrolul, acidul cafeic, catehina, epicatehina și procianidinele.Item SYNTHESIS OF QUERCETIN FUNCTIONALIZED CHITOSAN AND DETERMINATION OF ANTIOXIDANT PROPERTIES(2023) Gonța, Maria; Duca, Gheorghe; Sârbu, Elena; Robu, Ștefan; Mocanu, LarisaThis paper is dedicated to the synthesis of a copolymer with reducing properties obtained by functionalizing chitosan with quercetin and determining the antioxidant activity of the derivatives obtained depending on the molar mass of the polymer. For this purpose, low molecular weight chitosan was obtained by oxidizing commercial chitosan with hydrogen peroxide and further functionalization with quercetin by the covalent grafting method. The functionalization process was performed through the following steps: functionalization of chitosan with ethyl chloroformate to increase the reactivity of the amine group to the hydroxyl group of quercetin and grafting the quercetin molecule to the synthesized intermediate. The comparative antioxidant properties of the composite obtained by grafting technical chitosan with quercetin and by grafting low molecular weight chitosan were studied by the DPPH (2,2-diphenyl-1-picrylhydrazyl radical) method. The obtained results indicate that a decrease in the molecular weight of chitosan contributed to its grafting with quercetin. As a result, the functionalized polymer composite acquired a higher antioxidant activity and can be successfully used to inhibit the oxidation of various organic substrates in the cosmetic, food and pharmaceutical industries.Item NOVEL 2-FORMYLPYRIDINE 4-ALLYL-S- METHYLISOTHIOSEMICARBAZONE AND ZN(II), CU(II), NI(II) AND CO(III) COMPLEXES: SYNTHESIS, CHARACTERIZATION, CRYSTAL STRUCTURE, ANTIOXIDANT, ANTIMICROBIAL AND ANTIPROLIFERATIVE ACTIVITY(2019) Balan, Greta; Usataia, Irina; Graur, Vasilii; Ciumacov, Iurie; Petrenko, Peter; Gudumac, Valentin; Gulea, Aurelian; Pahonțu, Elena; Burduniuc, OlgaNew zinc (II), copper (II), nickel (II) and cobalt (III) complexes, [Zn (HL)2]I2 (1), [Cu (HL)Cl2] (2), [Cu (HL)Br2] (3), [Cu (HL)(H2O)2](ClO4)2 (4), [Ni (HL)2]I2·H2O (5), [Co(L)2]Cl (6), [Co(L)2]NO3 (7), [Co(L)2]I·[Co(L)2](I3) (8) were obtained with 2-formylpyridine 4-allyl-S-methylisothiosemicarbazone (HL). The isothiosemicarbazone ligand was characterized by NMR (1H and 13C), IR spectroscopy and X-ray diffraction. All the complexes were characterized by elemental analysis, IR, UV–Vis, ESI-MS spectroscopy, molar conductivity, magnetic susceptibility measurements. X-ray diffraction analysis on the monocrystal and powder elucidated the structure of the complexes 1, 5, 7 and 8. The ligand and the complexes were tested for their antioxidant and antimicrobial activity against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Candida albicans. Also, the antiproliferative properties of these compounds on human leukemia HL-60, human cervical epithelial HeLa, human epithelial pancreatic adenocarcinoma BxPC-3, human muscle rhabdomyosarcoma spindle, large multinucleated RD cells and normal MDCK cells have been investigated. The nickel complex 5 and cobalt complexes 6, 7 showed promising antiproliferative activity and low toxicity.Item SYNTHESIS, CHARACTERIZATION, CRYSTAL STRUCTURE OF NOVEL CU (II), CO (III), FE (III) AND CR (III) COMPLEXES WITH 2‐ HYDROXYBENZALDEHYDE‐4‐ALLYL‐S‐METHYLISOTHIOSEMICARBAZONE: ANTIMICROBIAL, ANTIOXIDANT AND IN VITRO ANTIPROLIFERATIVE ACTIVITY(2018) Pahonțu, Elena; Usataia, Irina; Graur, Vasilii; Ciumacov, Iurie; Petrenko, Peter; Gudumac, Valentin; Gulea, Aurelian2-Hydroxybenzaldehyde-4-allyl-S-methylisothiosemicarbazone and Cu (II), Co (III), Fe (III) and Cr (III) complexes were synthesized and characterized. The new obtained compounds were investigated by elemental analysis, magnetic susceptibility measurements, molar electric conductivity, IR, 1H NMR, 13C NMR, UV–Vis spectroscopy. In addition, the structure of the ligand and six complexes has been determined by single-crystal X-ray diffraction analysis. The Cu atom in complex 3 is penta-coordinated in a distorted square–pyramidal coordination geometry, while the metals in complexes 5–9 are in a distorted octahedral environment. For all compounds the antimicrobial activity was studied on a series of standard strains, such as Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Salmonella abony and Candida albicans. The in vitro antiproliferative activity of the ligand and complexes was screened on human leukemia HL-60 cells, human cervical epithelial HeLa cells, human epithelial pancreatic adenocarcinoma BxPC-3 cells, human muscle rhabdomyosarcoma spindle and large multinucleated RD cells. The primary screening on a wider series of cancer cells showed that copper coordination compound 2 manifests high activity towards HeLa, BxPC-3 and RD cancer cells, which is three–six times higher than the activity of doxorubicin. The selectivity index that is the ratio between the IC50 value for the normal MDCK cells and IC50 values for the cancer cells varies in the range 2.44–21.17. This index is 5.5–11 times higher for the copper coordination compound 2 than for the doxorubicin. Cr (III), Fe (III) and Co (III) coordination compounds 6–9 manifest high antioxidant activity towards ABTS•+ that exceeds 47–67 times the activity of Trolox.Item SINTEZA ȘI CERCETAREA PROPRIETĂȚILOR FARMACOFORE ALE UNOR N-(DIMETILFENIL) HIDRAZINCARBOTIOAMIDE(2023) Erhan, Tatiana; Garbuz, Olga; Ungur, Nicon; Gulea, AurelianThe present study was focused on the synthesis of some N-(dimethylphenyl)hydrazine carbothioamides 1-4, that contain the following N-substituents: 2,4-dimethylphenyl; 2,5-dimethylphenyl; 2,6-dimethylphenyl; 3,4-dimethylphenyl, to increase lipophilicity and N-(dimethylphenyl)-2-(pyridin-2-ylmethylidene)hydrazinecarbothioamides 5-8, analogous of Triapine. The structural formula of the compounds was characterized by means of spectroscopy: FT-IR, 1H-, and 13CRMN, and the molecular structure, for the first time, by means of X-ray diffraction. The study of antioxidant activity has shown that all compounds 1-8 are powerful antioxidants. N-(dimethylphenyl)-2-(pyridin2-ylmethylidene)hydrazinecarbothioamides 5-8 were tested as inhibitors of MCF-7 (breast cancer) cell proliferation. It was found that all the compounds exhibit activity comparable to that of Doxorubicin, among them the compound N-(2,5-dimethylphenyl)-2-(pyridin-2-ylmethylidene)hydrazinecarbothioamide 6, with IC50=0.8 μM/L, demonstrated the highest activity.Item NOVEL ANTIOXIDANTS BASED ON SELECTED 3D METAL COORDINATION COMPOUNDS WITH 2-HYDROXYBENZALDEHYDE 4,S-DIALLYLISOTHIOSEMICARBAZONE(2023) Graur, Vasilii; Mardari, Anastasia; Bouroș, Pavlina; Cravțov, Victor; Usataia, Irina; Ulchina, Ianina; Garbuz, Olga; Gulea, Aurelian2-Hydroxybenzaldehyde 4,S-diallylisothiosemicarbazone (HL) was synthesized and characterized by 1H, 13C NMR and FTIR spectroscopies. It exists in solution in two isomeric forms: cis (~25%) and trans (~75%). Six stable complexes were obtained by interaction of HL with copper(II), nickel(II), cobalt(III) and iron(III) salts: [Cu(L)Cl] (1), [Cu(L)NO3] (2), [Cu(3,4-Lut)(L)NO3] (3), [Ni(L)OAc] (4), [Co(L)2]Cl (5), [Fe(L)2]NO3 (6). The synthesized complexes have been studied by elemental analysis, FTIR, molar electrical conductivity and single crystal X-ray diffraction (6). For all compounds the antioxidant activity against cation radicals ABTS•+ was studied. All complexes and free ligand are more active than trolox that is used in medicine practice. Complex 4 (IC50=7.20µM) is the most active one. The introduction of heterocyclic amine did not improve the antioxidant activity. The introduction of S-allyl group into isothiosemicarbazone affected the activity of the synthesized substances, and in some cases the resulting complexes exhibit greater activity than complexes with isothiosemicarbazones with other S-radicals.Item SINTEZA COMBINAȚIILOR COORDINATIVE NOI ALE UNOR METALE 3D ÎN BAZA N(4)-(ACETAT DE ETIL) TIOSEMICARBAZONELOR 2-FORMIL ȘI 2-ACETIL PIRIDINEI. PROPRIETĂȚI ANTIOXIDANTE(2022) Rusnac, Anna; Garbuz, Olga; Șova, Sergiu; Gulea, AurelianThe 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.