Search

WOS: 000389165400048 The present study describes the synthesis, spectroscopic and electrochemical characterization of Cu(II)sulfathiazole (Hstz:4-amino-N-(1,3-thiazol-2-yl) benzene sulfonamide) complexes with dien (diethylenetriamine). The techniques used for the characterization have been single crystal X-ray diffraction, IR and EPR. The structural study indicated that the [Cu(stz)(2)dien] complex crystallizes in the monoclinic space group Pna2(1) with Z= 4. Two sulfathiazole anions were coordinated to the metal ion through N atom of the deprotonated sulfonamido group. Almost square-bipyramidal geometry with value of tau parameter approximate to 0.048 has been completed with three nitrogen atoms of dien molecule. The most important spectral features of the complex with its structural,properties were compared and discussed. The electrochemical study indicated the formation and the irreversibility of the mixed ligand metal complex. Biological study of the [Cu(stz)(2)dien]center dot 3H(2)O against Gram-positive and Gram-negative bacterial and fungal strains complex showed very strong antibacterial activity with MIC values ranging from 1 to 4 mu g/mL. (C) 2016 Elsevier Ltd. All rights reserved. Ondokuz Mayis University Research FundOndokuz Mayis University [PYO.FEN.1904.12.019] We would like thank to Ondokuz Mayis University Research Fund (PYO.FEN.1904.12.019) for financial support.

[M(saccharinato)2(H2O)4] (M = Cu2+, Ni2+, Co2+) react with nicotinamide to form mixed ligand complexes, [Cu(saccharinato)2(nicotinamide)(H2O)]⋅(H2O) (1) and [M(nicotinamide)2(H2O)4]⋅(saccharinate)2 (2: M = Ni2+; 3: M = Co2+), and their crystal structures have been determined by X-ray diffraction. In 1, the Cu2+ atom in an octahedral configuration is coordinated by two monodentate saccharinato ligands in the trans arrangement through the deprotonated ring nitrogens, by two bidentate nicotinamide ligands, one through the pyridyl ring nitrogen and the other through the amide oxygen, and by a water molecule, thus forming a nicotinamide-bridged one-dimensional extended structure. In the isomorphous complexes 2 and 3, the octahedral metal atom, which rides on a crystallographic center of symmetry, is coordinated by two monodentate nicotinamide ligands through the ring nitrogens and four water molecules to form a discrete [M(nicotinamide)2(H2O)4]2 + structural unit, which captures up and down two saccharinate ions, each through three hydrogen bonds: two hydrogen bonds between two water ligands and the ring N and the carbonyl O atoms and one between the amide N of the nicotinamide ligand and the carbonyl O.

WOS: 000348955300017 PubMed: 25485867 In this study, [Ni(dien)(2)]center dot smz(2)center dot(Hsmz: sulfamethazine and dien: diethylenetriamine) complex has been synthesized and its crystal structure has been determined by X-ray diffraction technique. The title complex crystallizes in orthorhombic system with space group Pbnb [a=8.556(5), b=16.228(5), c = 28.209(5) angstrom, V = 3917(3) angstrom(3) and Z= 4 . The nickel(II) ion has distorted octahedral coordination geometry. The metal atom, which rides on a crystallographic center of symmetry, is coordinated by six nitrogen atoms of two dien ligands to form a discrete [Ni(dien)(2)](2+) unit, which captures two sulfamethazine ions, each through intermolecular hydrogen bonds. The powder EPR spectrum of Cu2+ doped Ni(II) complex was recorded at room temperature. The vibrational investigation has been carried out by considering the characteristic bands related to the functional groups of the complex. The electrochemical behavior of Ni(II) ions in the presence and in the absence of smz and dien were studied by square wave and cyclic voltammetry. A well-defined irreversible peak at -1.112V different from those of the Ni(II)-smz (-0.876 V) and the Ni(II)-dien complex (-1.064 V) was observed in the solution containing Ni(II) ions, which was attributed to the formation of the new mixed ligand complex of Ni(II) with smz and dien. (C) 2014 Elsevier B.V. All rights reserved. Ondokuz Mayis University Research FundOndokuz Mayis University [PYO.FEN.1904.09.025] We would like thank to Ondokuz Mayis University Research Fund (PYO.FEN.1904.09.025) for financial support and also Prof.Dr.Orhan Buyukgungor for collecting XRD data.

To investigate the effects of noise on mismatch negativity (MMN) responses and the possible benefits of an adaptive directional BEAM microphone in noise during MMN recordings, and to compare the cochlear implant-evoked potential results with normal hearing subjects. Materials and methods: /da/ and /di/ speech stimuli were used to elicit MMN responses in 11 Freedom cochlear implant users and in 11 normal hearing subjects. Speech noise was delivered at 80 dB sound pressure level (-10 dB signal-to-noise ratio). All subjects were tested in quiet and noisy conditions. To compare the microphone effects, MMN responses for the cochlear implant group were recorded with an omnidirectional and adaptive directional BEAM microphone mode in noise. Results: The MMN responses of the cochlear implantees and the normal hearing group were remarkably similar in terms of latency, amplitude, and morphology in both quiet and noisy conditions. MMN peak latencies were significantly prolonged in the noisy conditions compared to the quiet conditions for both groups. There was a significant decrease in MMN latencies when using an adaptive directional microphone in noise. Conclusion: MMN could be a useful tool to evaluate postoperative cortical auditory performance. BEAM technology provides an ease of discrimination similar to quiet settings for cochlear implant recipients in noisy environments (BEAM and Freedom are trademarks of Cochlear Limited).

Naumov, Pance/0000-0003-2416-6569 WOS: 000167079800001 Four novel mixed ligand complexes of Cu(II), Co(II), Ni(II) and Zn(ll) with saccharin and nicotinamide were synthesised and characterised on the basis of elemental analysis, FT-IR spectroscopic study, W-Vis spectrometric and magnetic susceptibility data. The structure of the Cu (II) complex is completely different from those of the Co(II), Ni(ZI) and Zn(II) complexes. From the frequencies of the saccharinato CO and SO2 modes, it has been proven that the saccharinato ligands in the structure of the Cu complex are coordinated to the metal ion ([Cu(NA)(2)(Sac)(2)(H2O)], where NA - nicotinamide, Sac - saccharinato ligand or ion), whilst in the Co(II), Ni(II) and Zn(II) complexes are uncoordinated and exist as ions ([M(NA)(2)(H2O)(4)](Sac)(2)). (C) 2001 Elsevier Science B.V. All rights reserved.

Polymeric copper(II), [Cu(μ-dpc)(μ-4-hymp)] n (1), and monomeric nickel(II), [Ni(dpc)(4-hymp)(H2O)2]·H2O (2), (dpc: dipicolinate, 4-hymp: 4-hydroxymethyl pyridine), dipicolinate complexes have been prepared and characterized by spectroscopic (IR, UV–Vis, EPR), thermal (TG/DTA), X-ray diffraction technique and electrochemical methods. In both the dipicolinate complexes, the dpc dianion acts as a tridentate ligand. In polymeric copper(II) complex, the 4-hymp and dpc ligands adopt a bridging position between the Cu(II) centers, forming the elongated octahedral geometry. The polymeric chains are linked to one another via O–H···O hydrogen bond interactions, forming the 3-D polymeric structure. The Ni(II) ion is bonded to dpc ligand through pyridine N atom together with one O atom of each carboxylate group, two aqua ligands and N pyridine atom of 4-hymp, forming the distorted octahedral geometry. The Ni(II) complexes are connected to one another via O–H···O hydrogen bonds, forming R 4 2 (18) motifs in 2-D pattern. The powder EPR spectra of copper(II) complex have indicated that the paramagnetic center is in rhombic symmetry with the Cu2+ ion having distorted octahedral geometry. IR and UV–Vis spectroscopes all agree with the observed crystal structure.

Naumov, Pance/0000-0003-2416-6569; Ibrahim, Abdul Razak/0000-0002-1982-9375 WOS: 000171453800009 The Cd atom in the title compound, [Cd(C7H4NO3S)(2) (C6H6N2O)(2) (H2O)(2)], lies on an inversion centre and is six-coordinate in an all-trans octahedral geometry. Hydrogen bonds involving a water molecule and the amido group of a nicotinamide ligand link adjacent molecules into layers.

As a class of materials, metal phosphonates have been known for almost 30 years, but in recent years the research has expanded rapidly due to the important applications of metal bisphosphonate compounds in industrial processes such as ion-exchange, catalysis and sorption [1-3]. Recently, several metal complexes of clodronate, (dichloromethylene)-bisphosphonate, Cl2MBP, which is one of the best-documented bisphosphonates used effectively in medical applications, and its symmetrical dialkyl ester derivatives, have been prepared for studying the properties of solid materials [4]. The arrangement of metal complexes of bisphosphonates is dependent on the size of the organic group connected to the phosphonate groups, and also on the number of donor atoms of the ligand and on the degree of protonation of the phosphonate group [2]. In this study, a new, selective and simple method for the preparation of amide ester derivatives of Cl2MBP, has been developed. Four metal complexes of one of these synthesized ligands, P-piperidinium-P umethyl-(dichloromethylene)bis-phosphonate have been prepared in order to study the effect of the cyclic amine group on the complexing properties of the ligand and on the dimensionalities of its metal complexes. The compounds were crystallised by the gel method, and the structures of the complex crystals were characterized by single crystal X-ray diffraction methods, elemental analyses and thermal analyses. The methyl ester of piperidine derivative of Cl2MBP ligand forms the first wheel-like metal complex of bisphosphonate; the packing of the copper complex consist of channels occupied by aqua ligands and lattice water molecules. The complex, which has a unique hexameric structure, differs from rather common heptanuclear transition metal clusters such as Cu6Na, Co6Na, Fe6Na, Zn7, Mn7 and Cu7, where the seventh metal ion occupies the central position as a cation template. The other three compounds are polymers; Mg, Zn and Cd complexes consist of one-dimensional chains with different composition. In addition, in the case of the zinc complex, the coordinated Na cations hold the chains together forming a two-dimensional layered construction. Divalent metal cations are capable of forming different compounds with the methyl ester of piperidine derivative of clodronic acid. These kinds of structures provide new information about the ability of the amino derivatives of clodronic acid to form polymeric structures and microporous materials that can be utilized in chemical applications.