| 1. |
- Gyepesova, Dalma, et al.
(författare)
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Structural aspects of some Cu(II) complexes containing Schiff base.
- 2004
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Ingår i: Abstracts, ECM-22, 26-31 August 2004, Budapest, Hungary, Acta Cryst.. - 9639319406 ; A60, s. 266-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A group of copper(II) complexes containing Schiff bases,derived from salicylaldehyde and various amino acids, isinteresting due to their biological activities. Structures of (N-salicylidene-rac-glutamato)(1-methylimidazole)Cu(II) I, (Nsalicylidene-rac-glutamato)(2-methylimidazole)Cu(II) II and (N-salicylidene-L-glutamato)(2-ethylimidazole)Cu(II)III have been determined. Electron structure of thesecompounds has been investigated by the B3LYP method.In the all here presented complexes three donor atoms (O, Nand O) of the Schiff base and a fourth donor atom from theimidazole ligand (N) define the basal plane of Cu(II).Depending on different substituents R1 and R2 on theimidazole ring, changes of coordination sphere of Cu(II) isvarying (square-planar or square-pyramidal) as well as way of packing of molecules in the crystal.
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| 2. |
- Langer, Vratislav, 1949, et al.
(författare)
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(1-Methylimidazole)(N-salicylidene-rac-glutamato)copper(II)
- 2003
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Ingår i: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E59:12, s. m1181-m1183
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Tidskriftsartikel (refereegranskat)abstract
- The title racemic compound, [Cu(C12H11NO5)(C4H6N2)], adopts a square-planar copper(II) coordination mode with the tridentate N-salicylidenglutamato Schiff base dianion and the 1-methylimidazole ligand. Dimers of centrosymmetrically related molecules are formed. The theoretical investigation of the electronic structure of the title compound by the B3LYP method is presented.
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| 3. |
- Langer, Vratislav, 1949, et al.
(författare)
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Crystal and electronic structure of aqua(N-salicylidene-methylester-L-glutamato)Cu(II) monohydrate
- 2004
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Ingår i: Zeitschfrift für Kristallographie. - : Walter de Gruyter GmbH. - 0044-2968. ; 219:2, s. 112-116
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Tidskriftsartikel (refereegranskat)abstract
- The absolute structure of the title compound, CuNC13H17O7, has been determined. The crystal structure consists of the molecular units Cu(N-sal-5-met-L-glu)(H2O) connected by a three-dimensional network of hydrogen bonds. The coordination polyhedron in the complex is approximately square-pyramidal with a pentacoordinated Cu(II) atom. The base of the pyramid is formed by nitrogen and oxygen atoms belonging to the molecule, while the apex of the pyramid contains a weakly bonded oxygen atom of the carboxylic group of another molecule. The B3LYP/SVP method and basis set in Gaussian98 was used for quantum chemical calculation of the nature of CuX (X = O, N) bonds. While the calculated dissociation energy of the weakly bonded crystalline water is only 17.2 kJ/mol, the bonding energy of the water molecule coordinating to the Cu atom is 62.3 kJ/mol.
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| 4. |
- Langer, Vratislav, 1949, et al.
(författare)
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Dimeric (isoquinoline)(N-salicylidene-D,L-glutamato)copper(II) ethanol solvate
- 2009
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Ingår i: Acta Crystallographica Section C: Crystal Structure Communications. - 0108-2701 .- 1600-5759. ; C65:5, s. m208-m210
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Tidskriftsartikel (refereegranskat)abstract
- The title racemic complex, bis[μ-N-(2-oxidobenzylidene)-D,L-glutamato(2-)]bis[(isoquinoline)copper(II)] ethanol disolvate, [Cu2(C12H11NO5)2(C9H7N)2]·2C2H6O, adopts a square-pyramidal CuII coordination mode with a tridentate N-salicylideneglutamato Schiff base dianion and an isoquinoline ligand bound in the basal plane. The apex of the pyramid is occupied by a phenolic O atom from the adjacent chelate molecule at an apical distance of 2.487(3) Å, building a dimer located on the crystallographic inversion center. The Cu...Cu spacing within the dimers is 3.3264(12) Å. The ethanol solvent molecules are hydrogen bonded to the dimeric complex molecules, forming infinite chains in the a direction. The biological activity of the title complex has been studied.
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| 5. |
- Langer, Vratislav, 1949, et al.
(författare)
-
(N-salicylidene-D,L-glutamato) (2-methylimidazole)copper(II).
- 2004
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Ingår i: Acta Crystallographica Section E: Structure Reports Online. - 1600-5368. ; E60:1, s. m129-m132
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Tidskriftsartikel (refereegranskat)abstract
- The title racemic compound, [Cu(C12H11NO5)(C4H6N2)], adopts a square-pyramidal Cu(II) coordination with the tridentate N-salicylideneglutamate Schiff base dianion and the 2-methylimidazole ligand in the basal plane. The apex of the pyramid is occupied by a carboxylic acid O atom from the neighbouring chelate at a distance of 2.479(4)Å, leading to infinite one-dimensional chains along the crystallographic a axis. Strong N-H...O and O-H...O hydrogen bonds form a helix parallel to the c axis. The electronic structure of the title compound has also been investigated by the B3LYP method.
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| 6. |
- Langer, Vratislav, 1949, et al.
(författare)
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Novel type of Cu(II) complex containing Schiff base
- 2004
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Ingår i: Abstracts, ECM-22, 26-31 August 2004, Budapest, Hungary, Acta Cryst.. - 9639319406 ; A60, s. 221-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Recently, special interest has been devoted to the group ofcopper(II) complexes containing Schiff bases, derived fromsalicylaldehyde and various amino acids, and N-, or O- donorneutral ligands due to their biological activities. From this group of substances the structures of (N- salicylidene-racglutamato)(1-methylimidazole)Cu(II), (N-salicylidenerac-glutamato)(2-methylimidazole)Cu(II), (N-salicylidene-L-glutamato)(2-ethylimidazole)Cu(II) and aqua(Nsalicylidene-methylester-L-glutamato)Cu(II)monohydrate have been determined. Electronic structure of these compounds has been investigated by the B3LYP method. A continuation of these studies is a new complex transbis(ethanol)tetrakis(imidazole)Cu(II)(2+) bis[µ-(N-salicylidene-L-glutamato-N,O)-κO:κO´-(imidazole)Cu(II)](2-)presented here.This complex has quite spectacular structural features. Bothions are located on inverse centre. The cation is mononuclear, while the anion is binuclear. The quantum chemical calculation of the electronic structure has also been done by the B3LYP method.
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