| 1. |
- Massoud, Al-Shimaà A A, 1980, et al.
(författare)
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Bis 4,5-diazafluoren-9-one silver(I) nitrate: synthesis, X-ray structures, solution chemistry, hydrogel loading, DNA coupling and anti-bacterial screening
- 2011
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Ingår i: New Journal of Chemistry. - : Royal Society of Chemistry (RSC). - 1369-9261 .- 1144-0546. ; 35:3, s. 640-648
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Tidskriftsartikel (refereegranskat)abstract
- Synthesis of bis-4,5-diazafluoren-9-one silver(I) nitrate I (dafone = 4,5-diazafluoren-9-one) and the low temperature X-ray single crystal structure of [Ag(4,5-diazafluoren-9-one)2NO3], crystal form 1, and a re-determination of [Ag(4,5-diazafluoren-9-one)2]NO3 . H2O, crystal form 2 are presented. Crystal form 1 has a distorted trigonal planar coordination geometry around Ag(I) with an N-Ag-N bond angle of 123.45(7)o. Crystal form 2 has a perfect linear coordination around Ag, with N-Ag-N 180.0o. Compound I was characterized by 1H-NMR, biological activity and ESI-MS in DMSO at room temperature. The biological activity was determined against 6 different resistant clinical isolates; two Gram-positive (Staphylococcus aureus and Streptococcus pyogenes) and four Gram-negative (Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, and Salmonella sp.) in comparison with 15 known antibiotics used in the treatment of diabetic foot infections. Compound I showed broad spectrum activity against all the test organisms. P. mirabilis and S. aureus and K. pneumoniae were the most sensitive clinical isolates (MIC = 4, 6 and 4 μg ml-1, respectively). Three different hydrogels containing I or Ag2SO4 were prepared and the antimicrobial activity against Ps. aeruginosa (ATCC 15442) compared, showing more or less equal activity on a weight basis, but I seems to have a significant better performance per silver ion. The Ag(I) complex also binds more effectively to calf thymus DNA than the dafone ligand itself.
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| 2. |
- Abu-Youssef, Morsy A. M., et al.
(författare)
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Synthesis, Crystal Structure, Quantum Chemical Calculations, DNA Interactions, and Antimicrobial Activity of [Ag(2-amino-3-methylpyridine)2]NO3 and [Ag(pyridine-2-carboxaldoxime)NO3]
- 2010
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Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 49:21, s. 9788-9797
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Tidskriftsartikel (refereegranskat)abstract
- [Ag(2-amino-3-methylpyridine)2]NO3 (1) and [Ag(pyridine-2-carboxaldoxime)NO3] (2) were prepared from corresponding ligands and AgNO3 in water/ethanol solutions, and the products were characterized by IR, elemental analysis, NMR, and TGA. The X-ray crystal structures of the two compounds show that the geometry around the silver(I) ion is bent for complex 1 with nitrate as an anion and trigonal planar for complex 2 with nitrate coordinated. ESI-MS results of solutions of 2 indicate the independent existence in solution of the [Ag(pyridine-2-carboxaldoxime)]+ ion. The geometries of the complexes are well described by DFT calculations using the ZORA relativistic approach. The compounds were tested against 14 different clinically isolated and four ATCC standard bacteria and yeasts and also compared with 17 commonly used antibiotics. Both 1 and 2 exhibited considerable activity against S. lutea, M. lutea, and S. aureus and against the yeast Candida albicans, while 2-amino-3-methylpyridine is slightly active and pyridine-2-carboxaldoxime shows no antimicrobial activity. In addition, the interaction of these metal complexes with DNA was investigated. Both 1 and 2 bind to DNA and reduce its electrophoretic mobility with different patterns of migration, while the ligands themselves induce no change.
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| 3. |
- Massoud, Al-Shimaà A A, 1980, et al.
(författare)
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2D Bipyrimidine silver(I) nitrate: Synthesis, X-ray structure, solution chemistry and anti-microbial activit
- 2011
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Ingår i: Inorganic Chemistry Communication. - : Elsevier BV. - 1387-7003. ; 14:4, s. 550-553
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Tidskriftsartikel (refereegranskat)abstract
- Synthesis and X-ray single crystal structure analysis of the compound {[Ag2(μ2-bpym)(μ-O-NO3)2]}n, (1), (where bpym = 2,2′-bipyrimidine) are presented. Compound (1) has a (6,3)-2D honeycomb structure with a tetrahedral coordination geometry around the Ag(I) ion. In contrary to the solid state structural investigation, ESI-MS for (1) in solution shows a strong peak at m/z 423.0269 which indicates that the [Ag(bpym)2]+ cation is dominating instead of [Ag2(bpym)]2+. The anti-microbial activity of (1) was screened against 15 multi-drug resistant bacteria in comparison to silver(I) sulphadiazine and it showed a high activity against Burkholderia mallei which causes glanders; with a MIC value of 4 μg/ml.
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| 4. |
- Massoud, Al-Shimaà A A, 1980, et al.
(författare)
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Effects of Different Substituents on the Crystal Structures and Antimicrobial Activities of Six Ag(I) Quinoline Compounds
- 2013
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Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 52:7, s. 4046-4060
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Tidskriftsartikel (refereegranskat)abstract
- The syntheses and single crystal X-ray structures of [Ag(5-nitroquinoline)(2)]NO3 (1), [Ag(8-nitroquinoline)(2)]NO3 center dot H2O (2), [Ag(6-methoxy-8-nitroquinoline)(NO3)](n) (3), [Ag(3-quinolinecarbonitrile)(NO3)](n) (4), [Ag(3-quinolinecarbonitrile)(2)]NO3 (5), and [Ag(6-quinolinecarboxylic acid)(2)]NO3 (6) are described. As an alternative to solution chemistry, solid-state grinding could be used to prepare compounds 1 and 3, but the preparation of 4 and 5 in this way failed. The Ag(I) ions in the monomeric compounds 1, 2, 5, and 6 are coordinated to two ligands via the nitrogen atoms of the quinoline rings, thereby forming a distorted linear coordination geometry with Ag-N bond distances of 2.142(2)-2.336(2) angstrom and N-Ag-N bond angles of 163.62(13)degrees-172.25(13)degrees. The 1D coordination polymers 3 and 4 contain Ag(I) centers coordinating one ligand and two bridging nitrate groups, thereby forming a distorted trigonal planar coordination geometry with Ag-N bond distances of 2.2700(14) and 2.224(5) angstrom, Ag-O bond distances of 2.261(4)-2.536(5) angstrom, and N-Ag-O bond angles of 115.23(5)degrees-155.56(5)degrees. Hirshfeld surface analyses of compounds 1-6 are presented as d(norm) and curvedness maps. The d(norm) maps show different interaction sites around the Ag(I) ions, i.e., Ag center dot center dot center dot Ag interactions and possible O-H center dot center dot center dot O, C-H center dot center dot center dot O, C-H center dot center dot center dot N, and C-H center dot center dot center dot C hydrogen bonds. Curvedness maps are a good way of visualizing pi-pi tacking interactions between molecules. The antimicrobial activities of compounds 1, 2, and 6 were screened against 15 different multidrug-resistant strains of bacteria isolated from diabetic foot ulcers and compared to the antimicrobial activities of the clinically used silver sulfadiazine (SS). Compound 2 showed activity similar to SS against this set of test organisms, being active against all strains and having slightly better average silver efficiency than SS (5 vs 6 mu g Ag/mL). Against the standard nonresistant bacterial strains of Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis, and Streptococcus pyogenes, compound 1 performed better than silver nitrate, with an average MIC of 6 mu g Ag/mL versus 18 mu g Ag/mL for the reference AgNO3. Electrospray ionization mass spectrometry (ESI-MS) analyses of compounds 3 and 6 in DMSO/MeOH confirm the two-coordinated Ag+ complexes in solution, and the results of the H-1 NMR titrations of DMSO solutions of 5-nitroquinoline and 8-nitroquinoline with AgNO3 in DMSO suggest that 5-nitroquinoline is more strongly coordinated to the silver ion.
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| 5. |
- Massoud, Al-Shimaà A A, 1980, et al.
(författare)
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The coordination polymer poly[(μ3-3-aminocarbonylpyrazine-2-carboxylato-κ3N1:O2:O2')silver(I)]
- 2011
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Ingår i: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C67:1, s. m1-m4
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Tidskriftsartikel (refereegranskat)abstract
- The title compound, [Ag(C6H4N3O3)]n or [Ag(pyzca)]n (where pyzca is 3-aminocarbonylpyrazine-2-carboxylate), (I), was obtained by silver-catalysed partial hydrolysis of pyrazine-2,3-dicarbonitrile in aqueous solution. The compound has a distorted trigonal-planar coordination geometry around the AgI ion, with each ligand bridging three AgI ions to form a one-dimensional strand of molecules parallel to the b axis. An extensive hydrogen-bond pattern connects these strands to form a three-dimensional network of mog topology.
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| 6. |
- Soliman, S.M., et al.
(författare)
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Towards the chemical control of molecular packing: syntheses and crystal structures of three trans-[NiL4(NCS)2] complexes
- 2014
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Ingår i: Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials. - 2052-5206 .- 2052-5192. ; 70:1, s. 115-125
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Tidskriftsartikel (refereegranskat)abstract
- Three nickel(II) isothiocyanato complexes of the formulatrans-[NiL4(NCS)2] (L = ethylisonicotinate, methylisonicotinateand 4-benzoylpyridine) have been prepared: [Ni(ethylisonicotinate)4(NCS)2] (I), [Ni(methylisonicotinate)4(NCS)2](II) and [Ni(4-benzoylpyridine)4(NCS)2] (III). All threecomplexes are monomeric and have a distorted octahedralgeometry around NiII. Despite their apparent molecularsimilarity, the crystal density of (III) (1.454 g cm 3) issignificantly higher than that of (I) and (II) (both1.408 g cm 3), suggesting that the molecular packing is mostefficient in (III). A study of the molecular Hirshfeld surfaces,together with density functional theory (DFT) calculations,provide insights into the origin of the molecular packingfeatures, and it is suggested that the greater crystal density of(III) results from smaller intermolecular electrostatic repulsions.
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