👤 Ermakova, E. A.

Abstract Complex compounds [CuL(phen)(H2O)(NO3)]NO3 (1), [CuL(bipy)(NO3)2]·2EtOH (2), [CuL2(H2O)2 (NO3)2] (2a), [CuL(dmbipy)(NO3)2]·3EtOH (3), and [CuL2(NO3)2] (3a), where L is 3-(5-phenyl-2H-tetrazol-2-yl)pyridine, phen is 1,10-phenanthroline, bipy is 2,2′-bipyridine, and dmbipy is 4,4′-dimethyl-2,2′-bipyridine, are obtained and structurally characterized. It is shown that L behaves as the monodentate ligand being coordinated by the nitrogen atom of the pyridine ring. The coordination polyhedron made of copper atoms is a square pyramid in complexes 1 and 3, a distorted octahedron and a distorted square in complexes 2a and 3a respectively. Complex 1 is characterized by the elemental analysis, powder X-ray diffraction, and IR spectroscopy. Furthermore, its cytotoxic properties are studied on human larynx carcinoma (Hep2), breast adenocarcinoma (MCF7), and non-tumor human fibroblast (MRC5) cell lines. Complex 1 is shown to exhibit the pronounced cytotoxic action (LC50(Hep2) = 4.1±0.4 µM and LC50(MCF7) = 4.9±0.1 µM), however, does not exhibit selectivity against tumor cell lines (LC50(MRC5) = = 3.06 ±0.02 µM). Show less

Nickel(II) complexes of 1H-tetrazol-5-acetic acid (H2L) and oligopyridines (1,10-phenanthroline /2,2’-bipyridine derivatives) have been synthesized and characterized by physicochemical methods (elemental and thermogravimetric analysis, powder X-ray diffraction, and IR spectroscopy). The behavior of the complexes in solution was studied by UV–Vis spectroscopy, conductometry, and mass spectrometry. The stability of the complexes over 48 h in aqueous solution and in phosphate-buffered saline was demonstrated using UV–Vis spectroscopy. These compounds were investigated for their cytotoxic and cytostatic activity against HepG2 (hepatocellular carcinoma), and Hep2 (larynx carcinoma) human cancer cell lines. Cytotoxicity was also studied on human non-cancerous cell line MRC-5 (lung fibroblast). All the compounds did not show cytotoxic activity against the tested cell lines in 1–50-µM concentration range. However, compounds showed a cytostatic effect against HepG2 and Hep2 cell lines. The most pronounced cytostatic properties were found for the complex [Ni(dmphen)2L]·2C2H5OH·2H2O (1). In addition, we report three new crystal structures: [Ni(phen)2L]·H2O, [Ni(dmbipy)2L]·2C2H5OH, and [Ni(dmphen)2L]·2C2H5OH·2H2O, where L2– behaves as a bidentate ligand which is coordinated to the Ni(II) ion via N,O atoms. Show less

Herein, we present the synthesis, characterization, and in vitro investigation of cytotoxic activity against cancer (HepG-2, MCF-7) and non-cancerous (Hek-293, MRC-5) cell lines of six copper(II) complexes with 1H-tetrazole-5-acetic acid (H2L) and secondary ligands, such as olygopyridines (dmphen – 4,7-dimethyl-1,10-phenanthroline, phendione – 1,10 phenanthroline-5,6-dione, 5-Cl-phen – 5-chloro-1,10-phenanthroline, phen – 1,10 phenanthroline, dmbipy – 2,2′-bi-4-picoline, bipy – 2,2′-bipyridine). These compounds were characterized by powder X-ray diffraction, IR spectroscopy, elemental, and thermogravimetric analysis. The behavior of the complexes in solution was studied by optical spectroscopy, conductometry, and EPR. The DNA binding constant has been obtained for complex 5 using UV–vis spectroscopy. The antimicrobial activity of the complexes has been investigated against E. coli, S. aureus, P. italicum, and C. steinii. In addition, eight new crystal structures were obtained: [Cu(5-Cl-phen)L]n·0.5DMSO·1.5H2O (3a), [Cu(phen)L]n·2.5nH2O (4·2.5nH2O), [Cu3(phen)2(H2O)(HL)2L2]n·6nH2O (4a), [Cu(dmbipy)L]n (5), [Cu(dmbipy)(HL)2] (5a), [Cu3(dmpiby)2(HL)2L2]n·2nH2O·2nC2H5OH (5b), [Cu(bipy)L]n (6), and [Cu(bipy)(H2O)L] (6a). Show less

Abstract A novel mononuclear manganese(II) complex with 5-methyltetrazole and 4,7-dimethyl-1,10-phenanthroline is synthesized and characterized by physico-chemical methods (elemental and powder XRD analyses, IR spectroscopy). It is shown by the single-crystal XRD analysis that the coordination environment of the manganese(II) atom is a distorted octahedron. The stability of the complex in an aqueous solution and in phosphate-buffered saline is studied by optical spectroscopy. The cytotoxic activity of the obtained compound is studied on human laryngeal carcinoma cells (Hep-2) and non-cancerous human fibroblasts (MRC-5). The complex exhibits pronounced cytotoxic properties in the studied concentration range: IC50 is 11.1±0.4 µM on the Hep-2 cancer cell line and 0.63±0.05 µM on the MRC-5 line. Show less

Abstract The complex [Zn(Phen)(H2O)L2] (I), where HL is 5-benzyltetrazole, Phen is 1,10-phenanthroline, was synthesized. The compound was characterized by standard physicochemical methods (elemental analysis, powder X-ray diffraction, IR spectroscopy). According to X-ray diffraction data (CCDC no. 2220597), zinc coordination environment in the crystal structure of I corresponds to a distorted trigonal bipyramid. The ligand HL is monodentate and is coordinated via tetrazolate ring nitrogen. The stability of complex I was studied by NMR spectroscopy in DMSO. The cytotoxic properties of the compound were assessed against HepG-2 (hepatocellular carcinoma) and MRC-5 (noncancerous human fibroblasts) cells. Complex I exhibits weak cytotoxic properties in the studied concentration range (1–100 µM). Show less