1
|
Ewert J, Glück C, Strasdeit H, Fischer L, Stressler T. Influence of the metal ion on the enzyme activity and kinetics of PepA from Lactobacillus delbrueckii. Enzyme Microb Technol 2018; 110:69-78. [DOI: 10.1016/j.enzmictec.2017.10.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/13/2017] [Accepted: 10/10/2017] [Indexed: 10/18/2022]
|
2
|
Nakajima T, Yamashiro C, Taya M, Kure B, Tanase T. Systematic Synthesis of Di‐, Tri‐, and Tetranuclear Homo‐ and Heterometal Complexes Using a Mononuclear Copper Synthon with a Tetradentate Amino Alcohol Ligand. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600142] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Takayuki Nakajima
- Department of Chemistry Faculty of Science Nara Women's University Kitauoya‐nishi‐machi 630‐8506 Nara Japan
| | - Chisako Yamashiro
- Department of Chemistry Faculty of Science Nara Women's University Kitauoya‐nishi‐machi 630‐8506 Nara Japan
| | - Megumi Taya
- Department of Chemistry Faculty of Science Nara Women's University Kitauoya‐nishi‐machi 630‐8506 Nara Japan
| | - Bunsho Kure
- Department of Chemistry Faculty of Science Nara Women's University Kitauoya‐nishi‐machi 630‐8506 Nara Japan
| | - Tomoaki Tanase
- Department of Chemistry Faculty of Science Nara Women's University Kitauoya‐nishi‐machi 630‐8506 Nara Japan
| |
Collapse
|
3
|
Fuchs M, Zevaco T, Dinjus E, Walter O. catena-Poly[[aqua-zinc(II)]-μ-N,N'-bis-(2-cyano-3-eth-oxy-3-oxoprop-1-en-yl)benzene-1,2-diaminido]. Acta Crystallogr Sect E Struct Rep Online 2014; 70:m187-8. [PMID: 24860317 PMCID: PMC4011238 DOI: 10.1107/s1600536814008381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 04/14/2014] [Indexed: 11/10/2022]
Abstract
The slightly yellow-coloured title complex, [Zn(C18H16N4O4)(H2O)] n , crystallizes with one mol-ecule in the asymmetric unit. The structure clearly shows the mer-η(4) O,O,N,N-binding mode of the N,N'-bis-(2-cyano-ethyl-propeno-yl)-1,2-di-amido-benzene ligand stabilizing the Zn centre of a distorted octa-hedral environment. The fifth coordination site in one apical position is held by a coordinating solvent water mol-ecule whereas the complete octa-hedral coordination sphere is completed by coordination of one N atom from a CN group of a neighbouring mol-ecule, leading to the final polymeric structure consisting of zigzag staggered chains in parallel orientation along the c-axis direction. Between the coord-in-ated water solvent molecule and the N atoms of uncoord-in-ated cyano-groups of neighboured units, two H-bridge bonds are formed. One of these H-bridge bonds is of inter- whereas the other of intra-strand nature, leading to a two-dimensional network parallel to (110) stabilizing the supramolecular structure. Six Zn-O or Zn-N bonds are found with lengths ranging from 2.061 (1) to 2.185 (1) Å and bond angles about the Zn atom are clustered in the ranges 79.83 (4)-104.21 (4) and 167.05 (4)-170.28 (4)°.
Collapse
Affiliation(s)
- Monica Fuchs
- IKFT, KIT-Campus Nord, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Thomas Zevaco
- IKFT, KIT-Campus Nord, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Eckhard Dinjus
- IKFT, KIT-Campus Nord, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Olaf Walter
- IKFT, KIT-Campus Nord, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| |
Collapse
|
4
|
Patra A, Bera M. Spectroscopic investigation of new water soluble and complexes for the substrate binding models of xylose/glucose isomerases. Carbohydr Res 2014; 384:87-98. [DOI: 10.1016/j.carres.2013.12.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 11/30/2013] [Accepted: 12/03/2013] [Indexed: 11/24/2022]
|
5
|
Garcia L, Lazzaretti M, Diguet A, Mussi F, Bisceglie F, Xie J, Pelosi G, Buschini A, Baigl D, Policar C. An intrinsically fluorescent glycoligand for direct imaging of ligand trafficking in artificial and living cell systems. NEW J CHEM 2013. [DOI: 10.1039/c3nj00380a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
6
|
|
7
|
Wałęsa-Chorab M, Gorczyński A, Kubicki M, Hnatejko Z, Patroniak V. Self-assembly of a tridentate Schiff-base ligand with Zn(II) in the presence of lanthanides: Novel crystal structures and spectroscopic properties. Polyhedron 2012. [DOI: 10.1016/j.poly.2011.08.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
8
|
Patra A, Sen TK, Bhattacharyya R, Mandal SK, Bera M. Diversity of carboxylate binding in a new tetranuclear zinc cluster: correlation between spectroscopic investigations and carboxylate binding modes. RSC Adv 2012. [DOI: 10.1039/c2ra01317g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
9
|
Chanu OB, Kumar A, Ahmed A, Lal R. Synthesis and characterisation of heterometallic trinuclear copper(II) and zinc(II) complexes derived from bis(2-hydroxy-1-naphthaldehyde)oxaloyldihydrazone. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2011.11.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
10
|
Takemura Y, Okui Y, Kure B, Nakajima T, Tanase T, Mikuriya M, Takahashi M. Octanuclear iron(III) complexes supported by Kemp’s tricarboxylate ligands. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2011.09.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
11
|
Bera M, Patra A. New dinuclear copper(II) and zinc(II) complexes for the investigation of sugar–metal ion interactions. Carbohydr Res 2011; 346:2075-83. [DOI: 10.1016/j.carres.2011.06.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Revised: 06/06/2011] [Accepted: 06/21/2011] [Indexed: 10/18/2022]
|
12
|
Seubert CK, Sun Y, Lan Y, Powell AK, Thiel WR. From a Simple Pyrazole‐Derived 1,2‐Amino Alcohol to Mono‐ and Multinuclear Complexes by Tailoring Hydrogen Bond Patterns. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201001231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Christoph K. Seubert
- Fachbereich Chemie, TU Kaiserslautern, Erwin‐Schrödinger‐Str. Geb. 54, 67663 Kaiserslautern, Germany, Fax: +49‐631‐2054647
| | - Yu Sun
- Fachbereich Chemie, TU Kaiserslautern, Erwin‐Schrödinger‐Str. Geb. 54, 67663 Kaiserslautern, Germany, Fax: +49‐631‐2054647
| | - Yanhua Lan
- Karlsruher Institut für Technologie (KIT), Institut fürAnorganische Chemie, Engesserstr. 15, 76131 Karlsruhe, Germany
| | - Annie K. Powell
- Karlsruher Institut für Technologie (KIT), Institut fürAnorganische Chemie, Engesserstr. 15, 76131 Karlsruhe, Germany
| | - Werner R. Thiel
- Fachbereich Chemie, TU Kaiserslautern, Erwin‐Schrödinger‐Str. Geb. 54, 67663 Kaiserslautern, Germany, Fax: +49‐631‐2054647
| |
Collapse
|
13
|
Gilg K, Mayer T, Ghaschghaie N, Klüfers P. The metal-binding sites of glycose phosphates. Dalton Trans 2009:7934-45. [PMID: 19771356 DOI: 10.1039/b909431h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In aqueous solution, the reducing sugar phosphates D-arabinose 5-phosphate, D-ribose 5-phosphate, D-fructose 1,6-bisphosphate, D-fructose 6-phosphate, D-glucose 6-phosphate and D-mannose 6-phosphate provide metal-binding sites at their glycose core on reaction with Pd(II)(en) or M(III)(tacn) residues (M = Ga, Co; en = ethylenediamine, tacn = 1,4,7-triazacyclononane). The individual species were detected by one- and two-dimensional NMR spectroscopy. The coordination patterns are related to the metal-binding modes of the respective parent glycoses. In detail, ribo- and arabinofuranose phosphate favour kappaO(1,3) coordination, whereas the ketofuranose core of fructose phosphate and fructose bisphosphate provides the kappaO(2,3) chelator thus maintaining the configuration of the respective major solution anomer. On palladium excess, D-fructose 6-phosphate is metallated twice in a unique kappaO(1,3):kappaO(2,4) metallation pattern. Dimetallation is also found for the aldohexose phosphates. A mixed glycose-core-phosphate chelation was detected for Pd(II)(en) and M(III)(tacn) residues with M = Al, Ga in the pH range just above the physiological pH for the D-fructose 1,6-bisphosphate ligand. The results are discussed in relation to D-fructose-1,6-bisphosphate-metabolism in class-II aldolases.
Collapse
Affiliation(s)
- Kathrin Gilg
- Department of Chemistry and Biochemistry of the Ludwig Maximilian University Munich, Butenandtstr. 5-13, D-81377 Munich, Germany
| | | | | | | |
Collapse
|
14
|
Sathisha MP, Budagumpi S, Kulkarni NV, Kurdekar GS, Revankar VK, Pai KSR. Synthesis, structure, electrochemistry and spectral characterization of (D-glucopyranose)-4-phenylthiosemicarbazide metal complexes and their antitumor activity against Ehrlich ascites carcinoma in Swiss albino mice. Eur J Med Chem 2009; 45:106-13. [PMID: 19854545 DOI: 10.1016/j.ejmech.2009.09.031] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2009] [Revised: 09/09/2009] [Accepted: 09/17/2009] [Indexed: 11/30/2022]
Abstract
The novel glycosyl saccharide derivative, (D-glucopyranose)-4-phenylthiosemicarbazide (LH) and its complexes, with cobalt(II), nickel(II), copper(II) and zinc(II) were synthesized, characterised and tested for cytotoxic effects. The copper complex, [CuLCl] inhibited Ehrlich Ascites Carcinoma (EAC) induced cancer cell lines in Swiss albino mice at LC50=1.94 x 10(-8) (LC50=2.76 x 10(-8) for cisplatin) and so distinctly better than free ligand and other complexes.
Collapse
Affiliation(s)
- M P Sathisha
- Department of Studies in Chemistry, Karnatak University, Pavate Nagar, Dharwad 580 003, Karnataka, India
| | | | | | | | | | | |
Collapse
|
15
|
Sathisha M, Revankar V. Interaction of Co(II), Ni(II), Cu(II), and Zn(II) with N,N′-(aldose)2-thiocarbohydrazide: synthesis, electrochemistry, and spectral characterization. J COORD CHEM 2009. [DOI: 10.1080/00958970902842463] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- M.P. Sathisha
- a Department of Chemistry , Karnatak University , Dharwad–580 003, India
| | - V.K. Revankar
- a Department of Chemistry , Karnatak University , Dharwad–580 003, India
| |
Collapse
|
16
|
Burkhardt A, Spielberg E, Simon S, Görls H, Buchholz A, Plass W. Hydrogen Bonds as Structural Directive towards Unusual Polynuclear Complexes: Synthesis, Structure, and Magnetic Properties of Copper(II) and Nickel(II) Complexes with a 2-Aminoglucose Ligand. Chemistry 2008; 15:1261-71. [DOI: 10.1002/chem.200800670] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
17
|
Burkhardt A, Spielberg ET, Görls H, Plass W. Chiral Tetranuclear μ3-Alkoxo-Bridged Copper(II) Complex with 2 + 4 Cubane-Like Cu4O4 Core Framework and Ferromagnetic Ground State. Inorg Chem 2008; 47:2485-93. [DOI: 10.1021/ic701777t] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anja Burkhardt
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Carl-Zeiss-Promenade 10, 07745 Jena, Germany
| | - Eike T. Spielberg
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Carl-Zeiss-Promenade 10, 07745 Jena, Germany
| | - Helmar Görls
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Carl-Zeiss-Promenade 10, 07745 Jena, Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Carl-Zeiss-Promenade 10, 07745 Jena, Germany
| |
Collapse
|
18
|
Storr T, Merkel M, Song-Zhao GX, Scott LE, Green DE, Bowen ML, Thompson KH, Patrick BO, Schugar HJ, Orvig C. Synthesis, Characterization, and Metal Coordinating Ability of Multifunctional Carbohydrate-Containing Compounds for Alzheimer's Therapy. J Am Chem Soc 2007; 129:7453-63. [PMID: 17511455 DOI: 10.1021/ja068965r] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Dysfunctional interactions of metal ions, especially Cu, Zn, and Fe, with the amyloid-beta (A beta) peptide are hypothesized to play an important role in the etiology of Alzheimer's disease (AD). In addition to direct effects on A beta aggregation, both Cu and Fe catalyze the generation of reactive oxygen species (ROS) in the brain further contributing to neurodegeneration. Disruption of these aberrant metal-peptide interactions via chelation therapy holds considerable promise as a therapeutic strategy to combat this presently incurable disease. To this end, we developed two multifunctional carbohydrate-containing compounds N,N'-bis[(5-beta-D-glucopyranosyloxy-2-hydroxy)benzyl]-N,N'-dimethyl-ethane-1,2-diamine (H2GL1) and N,N'-bis[(5-beta-D-glucopyranosyloxy-3-tert-butyl-2-hydroxy)benzyl]-N,N'-dimethyl-ethane-1,2-diamine (H2GL2) for brain-directed metal chelation and redistribution. Acidity constants were determined by potentiometry aided by UV-vis and 1H NMR measurements to identify the protonation sites of H2GL1,2. Intramolecular H bonding between the amine nitrogen atoms and the H atoms of the hydroxyl groups was determined to have an important stabilizing effect in solution for the H2GL1 and H2GL2 species. Both H2GL1 and H2GL2 were found to have significant antioxidant capacity on the basis of an in vitro antioxidant assay. The neutral metal complexes CuGL1, NiGL1, CuGL2, and NiGL2 were synthesized and fully characterized. A square-planar arrangement of the tetradentate ligand around CuGL2 and NiGL2 was determined by X-ray crystallography with the sugar moieties remaining pendant. The coordination properties of H2GL1,2 were also investigated by potentiometry, and as expected, both ligands displayed a higher affinity for Cu2+ over Zn2+ with H2GL1 displaying better coordinating ability at physiological pH. Both H2GL1 and H2GL2 were found to reduce Zn2+- and Cu2+- induced Abeta1-40 aggregation in vitro, further demonstrating the potential of these multifunctional agents as AD therapeutics.
Collapse
Affiliation(s)
- Tim Storr
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Burkhardt A, Buchholz A, Görls H, Plass W. Synthesis, Structure and Magnetic Properties of a Tetranuclear Copper(II) Complex on the Basis of a 2-Substituted Glucopyranoside Schiff Base Ligand. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200600404] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
20
|
Kato M, Sah AK, Tanase T, Mikuriya M. Tetranuclear Copper(II) Complexes Bridged by α-d-Glucose-1-Phosphate and Incorporation of Sugar Acids through the Cu4 Core Structural Changes. Inorg Chem 2006; 45:6646-60. [PMID: 16903719 DOI: 10.1021/ic060202h] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tetranuclear copper(II) complexes containing alpha-D-glucose-1-phosphate (alpha-D-Glc-1P), [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(bpy)4(H2O)2]X3 [X = NO3 (1a), Cl (1b), Br (1c)], and [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(phen)4(H2O)2](NO3)3 (2) were prepared by reacting the copper(II) salt with Na2[alpha-D-Glc-1P] in the presence of diimine ancillary ligands, and the structure of 2 was characterized by X-ray crystallography to comprise four {Cu(phen)}2+ fragments connected by the two sugar phosphate dianions in 1,3-O,O' and 1,1-O mu4-bridging fashion as well as a mu-hydroxo anion. The crystal structure of 2 involves two chemically independent complex cations in which the C2 enantiomeric structure for the trapezoidal tetracopper(II) framework is switched according to the orientation of the alpha-D-glucopyranosyl moieties. Temperature-dependent magnetic susceptibility data of 1a indicated that antiferromagnetic spin coupling is operative between the two metal ions joined by the hydroxo bridge (J = -52 cm(-1)) while antiferromagnetic interaction through the Cu-O-Cu sugar phosphate bridges is weak (J = -13 cm(-1)). Complex 1a readily reacted with carboxylic acids to afford the tetranuclear copper(II) complexes, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-CA)2(bpy)4](NO3)2 [CA = CH3COO (3), o-C6H4(COO)(COOH) (4)]. Reactions with m-phenylenediacetic acid [m-C6H4(CH2COOH)2] also gave the discrete tetracopper(II) cationic complex [Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)(CH2COOH))2(bpy)4](NO3)2 (5a) as well as the cluster polymer formulated as {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)2)(bpy)4](NO3)2}n (5b). The tetracopper structure of 1a is converted into a symmetrical rectangular core in complexes 3, 4, and 5b, where the hydroxo bridge is dissociated and, instead, two carboxylate anions bridge another pair of Cu(II) ions in a 1,1-O monodentate fashion. The similar reactions were applied to incorporate sugar acids onto the tetranuclear copper(II) centers. Reactions of 1a with delta-D-gluconolactone, D-glucuronic acid, or D-glucaric acid in dimethylformamide resulted in the formation of discrete tetracopper complexes with sugar acids, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-SA)2(bpy)4](NO3)2 [SA = D-gluconate (6), D-glucuronate (7), D-glucarateH (8a)]. The structures of 6 and 7 were determined by X-ray crystallography to be almost identical with that of 3 with additional chelating coordination of the C-2 hydroxyl group of D-gluconate moieties (6) or the C-5 cyclic O atom of D-glucuronate units (7). Those with D-glucaric acid and D-lactobionic acid afforded chiral one-dimensional polymers, {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-glucarate)(bpy)4](NO3)2}n (8b) and {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-lactobionate)(bpy)4(H2O)2](NO3)3}n (9), respectively, in which the D-Glc-1P-bridged tetracopper(II) units are connected by sugar acid moieties through the C-1 and C-6 carboxylate O atoms in 8b and the C-1 carboxylate and C-6 alkoxy O atoms of the gluconate chain in 9. When complex 7 containing d-glucuronate moieties was heated in water, the mononuclear copper(II) complex with 2-dihydroxy malonate, [Cu(mu-O2CC(OH)2CO2)(bpy)] (10), and the dicopper(II) complex with oxalate, [Cu2(mu-C2O4)(bpy)2(H2O)2](NO3)2 (11), were obtained as a result of oxidative degradation of the carbohydrates through C-C bond cleavage reactions.
Collapse
Affiliation(s)
- Merii Kato
- Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-higashi-machi, Nara 630-8285, Japan
| | | | | | | |
Collapse
|
21
|
Kato M, Tanase T, Mikuriya M. Dinuclear Copper(II) Complexes with {Cu2(μ-hydroxo)bis(μ-carboxylato)}+ Cores and Their Reactions with Sugar Phosphate Esters: A Substrate Binding Model of Fructose-1,6-bisphosphatase. Inorg Chem 2006; 45:2925-41. [PMID: 16562948 DOI: 10.1021/ic051942d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reactions of CuX2.nH2O with the biscarboxylate ligand XDK (H2XDK = m-xylenediamine bis(Kemp's triacid imide)) in the presence of N-donor auxiliary ligands yielded a series of dicopper(II) complexes, [Cu2(mu-OH)(XDK)(L)2]X (L = N,N,N',N'-tetramethylethylenediamine (tetmen), X = NO3 (1a), Cl (1b); L = N,N,N'-trimethylethylenediamine (tmen), X = NO3 (2a), Cl (2b); L =2,2'-bipyridine (bpy), X = NO3 (3); L = 1,10-phenanthroline (phen), X = NO3 (4); L = 4,4'-dimethyl-2,2'-bipyridine (Me2bpy), X = NO3 (5); L = 4-methyl-1,10-phenanthroline (Mephen), X = NO3 (6)). Complexes 1-6 were characterized by X-ray crystallography (Cu...Cu = 3.1624(6)-3.2910(4) A), and the electrochemical and magnetic properties were also examined. Complexes 3 and 4 readily reacted with diphenyl phosphoric acid (HDPP) or bis(4-nitrophenyl) phosphoric acid (HBNPP) to give [Cu2(mu-phosphate)(XDK)(L)2]NO3 (L = bpy, phosphate = DPP (11); L = phen, phosphate = DPP (12), BNPP (13)), where the phsophate diester bridges the two copper ions in a mu-1,3-O,O' bidentate fashion (Cu...Cu = 4.268(3)-4.315(1) A). Complexes 4 and 6 with phen and Mephen have proven to be good precursors to accommodate a series of sugar monophosphate esters (Sugar-P) onto the biscarboxylate-bridged dicopper centers, yielding [Cu2(mu-Sugar-P)(XDK)(L)2] (Sugar-P = alpha-D-Glc-1-P (23a and b), D-Glc-6-P (24a and b), D-Man-6-P (25a), D-Fru-6-P (26a and b); L = phen (a), Mephen (b)) and [Cu2(mu-Gly-n-P)(XDK)(Mephen)2] (Gly-n-P = glycerol n-phosphate; n = 2 (21), 3 (22)), where Glc, Man, and Fru are glucose, mannose, and fructose, respectively. The structure of [Cu2(mu-MNPP)(XDK)(phen)2(CH3OH)] (20) was characterized as a reference compound (H2MNPP = 4-nitrophenyl phosphoric acid). Complexes 4 and 6 also reacted with d-fructose 1,6-bisphosphate (D-Fru-1,6-P2) to afford the tetranuclear copper(II) complexes formulated as [Cu4(mu-D-Fru-1,6-P2)(XDK)2(L)4] (L = phen (27a), Mephen (27b)). The detailed structure of 27a was determined by X-ray crystallography to involve two different tetranuclear complexes with alpha- and beta-anomers of D-Fru-1,6-P2, [Cu4(mu-alpha-D-Fru-1,6-P2)(XDK)2(phen)4] and [Cu4(mu-beta-D-Fru-1,6-P2)(XDK)2(phen)4], in which the D-Fru-1,6-P2 tetravalent anion bridges the two [Cu2(XDK)(phen)2]2+ units through the C1 and C6 phosphate groups in a mu-1,3-O,O' bidentate fashion (Cu...Cu = 4.042(2)-4.100(2) A). Notably, the structure with alpha-D-Fru-1,6-P2 demonstrated the presence of a strong hydrogen bond between the C2 hydroxyl group and the C1 phosphate oxygen atom, which may support the previously proposed catalytic mechanism in the active site of fructose-1,6-bisphosphatase.
Collapse
Affiliation(s)
- Merii Kato
- Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-higashi-machi, Nara 630-8285, Japan
| | | | | |
Collapse
|
22
|
Sah AK, Tanase T, Mikuriya M. Tri- and Tetranuclear Copper(II) Complexes Consisting of Mononuclear Cu(II) Chiral Building Blocks with a Sugar-Derived Schiff's Base Ligand. Inorg Chem 2006; 45:2083-92. [PMID: 16499370 DOI: 10.1021/ic051862+] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new sugar-derived Schiff's base ligand N-(3-tert-butyl-2-hydroxybenzylidene)-4,6-O-ethylidene-beta-D-glucopyranosylamine (H3L1) has been developed which afforded the coordinatively labile, alcoholophilic trinuclear Cu(II) complex [Cu3(L1)2(CH3OH)(H2O)] (1). Complex 1 has been further used in the synthesis of a series of alcohol-bound complexes with a common formula of [Cu3(L1)2(ROH)2] (R = Me (2), Et (3), nPr (4), nBu (5), nOct (6)). X-ray structural analyses of complexes 2-6 revealed the collinearity of trinuclear copper(II) centers with Cu-Cu-Cu angles in the range of 166-172 degrees . The terminal and central coppers are bound with NO3 and O4 atoms, respectively, and exhibit square-planar geometry. The trinuclear structures of 2-6 can be viewed as the two {Cu(L1)}- fragments capture a copper(II) ion in the central position, which is further stabilized by a hydrogen-bonding interaction between the alcohol ligands and the sugar C-3 alkoxo group. Complex 2 exhibits a strong antiferromagnetic interaction between the Cu(II) ions (J = -238 cm(-1)). Diffusion of methanol into a solution of complex 1 in a chloroform/THF mixed solvent afforded the linear trinuclear complex [Cu(3)(L1)2(CH3OH)2(THF)2] (7). The basic structure of 7 is identical to complex 2; however, THF binding about the terminal coppers (Cu-O(THF) = 2.394(7) and 2.466(7) A) has introduced the square-pyramidal geometry, indicating that the planar trinuclear complexes 2-6 are coordinatively unsaturated and the terminal metal sites are responsible for further ligations. In the venture of proton-transfer reactions, a successful proton transfer onto the saccharide C-3 alkoxo group has been achieved using 4,6-O-ethylidene-d-glucopyranose, resulting in the self-assembled tetranuclear complex, [Cu4(HL1)4] (8), consisting of the mononuclear Cu(II) chiral building blocks, {Cu(HL1)}.
Collapse
Affiliation(s)
- Ajay K Sah
- Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-higashi-machi, Nara 630-8285, Japan
| | | | | |
Collapse
|
23
|
Sah AK, Tanase T. Amine mediated proton transfer reaction and C–Cl bond activation of solvent chloroform by a trinuclear copper(ii) complex of a glucopyranosylamine derived ligand. Dalton Trans 2006:3742-51. [PMID: 16883400 DOI: 10.1039/b606485j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An amine mediated C-Cl bond activation process of the solvent chloroform has been explored by a coordinatively labile trinuclear Cu(II) complex, [Cu3(L1)2(MeOH)(H2O)] (1), derived from N-(3-tert-butyl-2-hydroxybenzylidene)-4,6-O-ethylidene--D-glucopyranosylamine (H3L1). The effect of activation is extremely high with methylamine, resulting in the formation of [Cu(MeNH2)5]Cl2 (2) and [Cu(L2)2] (3; HL2 = 2-tert-butyl-6-[(methylimino)methyl]phenol), however, under identical conditions it is moderate with ethylamine resulting in the isolation of crystals of the intermediate amine bound trinuclear copper(II) complex, [Cu3(L1)2(EtNH2)2(MeOH)2] (5), which was further converted into the mononuclear complex, [Cu(HL1)(EtNH2)] (6), in a novel crystal-to-crystal transformation. The successive isolation of the ethylamine-bound tri- and mononuclear complexes, 5 and 6, supported the occurrence of proton transfer reactions, which might be a key step in C-Cl bond activation. The primary and secondary amines, 2-aminomethylpyridine, N,N-dimethylethylenediamine, and 1,4,7-triazacyclononane, also having chelating features further enhance the rate of activation. No activation has been noted in the case of triethylamine and N,N,N,N-tetramethylethylenediamine. Formation of a carbene-trapped compound, 2,6-xylyl isocyanide, was confirmed in the reaction of complex 1 with 1,4,7-triazacyclononane and 2,6-xylidine in CHCl3, suggesting that the C-Cl bond cleavage led to the generation of dichlorocarbene. In addition, the mononuclear complex 6 has been transformed into a homotrinuclear complex [Cu3(L1)2(MeOH)2] by treatment with Cu(II) ions in MeOH/CHCl3, suggesting the possibility that the former could be regarded as a suitable metalloligand for heterotrimetallic complex synthesis.
Collapse
Affiliation(s)
- Ajay K Sah
- Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-higashi-machi, Nara, 630-8285, Japan
| | | |
Collapse
|
24
|
Weston J. Mode of action of bi- and trinuclear zinc hydrolases and their synthetic analogues. Chem Rev 2005; 105:2151-74. [PMID: 15941211 DOI: 10.1021/cr020057z] [Citation(s) in RCA: 272] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jennie Weston
- Institut für Organische und Makromolekulare Chemie, Friedrich-Schiller-Universität, Jena, Germany.
| |
Collapse
|
25
|
Anda C, Bencini A, Berni E, Ciattini S, Chuburu F, Danesi A, Giorgi C, Handel H, Le Baccon M, Paoletti P, Tripier R, Turcry V, Valtancoli B. Mono- and Dinuclear CuII and ZnII Complexes of Cyclen-Based Bis(macrocycles) Containing Two Aminoalkyl Pendant Arms of Different Lengths. Eur J Inorg Chem 2005. [DOI: 10.1002/ejic.200400896] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
26
|
Storr T, Sugai Y, Barta CA, Mikata Y, Adam MJ, Yano S, Orvig C. Carbohydrate-Appended 2,2‘-Dipicolylamine Metal Complexes as Potential Imaging Agents. Inorg Chem 2005; 44:2698-705. [PMID: 15819555 DOI: 10.1021/ic048528i] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three discrete carbohydrate-appended 2,2'-dipicolylamine ligands were complexed to the {M(CO)(3)}(+) (M = (99m)Tc/Re) core: 2-(bis(2-pyridinylmethyl)amino)ethyl-beta-d-glucopyranoside (L(1)()), 2-(bis(2-pyridinylmethyl)amino)ethyl-beta-D-xylopyranoside (L(2)()), and 2-(bis(2-pyridinylmethyl)amino)ethyl-alpha-d-mannopyranoside (L(3)). An ethylene spacer is used to separate the carbohydrate moiety and the dipicolylamine (DPA) function in all three ligands. The Re complexes [Re(L(1-3))(CO)(3)]Br were characterized by (1)H and (13)C 1D/2D NMR spectroscopies, which confirmed the pendant nature of the carbohydrate moieties in solution. NMR measurements also established the long-range asymmetric effect of the carbohydrate functions on the chelating portion of the ligand. One analogue, [Re(L(1))(CO)(3)]Cl, was characterized in the solid state by X-ray crystallography. Further characterization was provided by IR spectroscopy, elemental analysis, conductivity, and mass spectrometry. Radiolabeling of L(1)-L(3) with [(99m)Tc(H(2)O)(3)(CO)(3)](+) afforded high yield compounds of identical character to the Re analogues. The radiolabeled compounds were found to be stable toward ligand exchange in the presence of a large excess of either cysteine or histidine over a 24-h period.
Collapse
Affiliation(s)
- Tim Storr
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | | | | | | | | | | | | |
Collapse
|
27
|
Benniston AC, Gunning P, Peacock RD. Synthesis and binding properties of hybrid cyclophane-azamacrocyclic receptors. J Org Chem 2005; 70:115-23. [PMID: 15624913 DOI: 10.1021/jo048621o] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three new azamacrocyclic-cyclophane hybrid receptors L(1), L(2), and L(3) have been synthesized that incorporate either 1,4,7,10-tetraazacyclododecane (cyclen) or 1,4,7-triazacyclononane (tacn) unit(s) tethered via a short amidic spacer to an electron donor and a H-bonding crown ether polycycle. The crown ether is designed to act as a host toward biologically relevant guests, whereas the macrocycle can coordinate a zinc(II) or a copper(II) ion. The pK(a) of this bound water in the zinc(II) complex of L(1) and L(2) is approximately 7.5. Isothermal calorimetry experiments carried out on [ZnL(1)(L2)(OH(2))](CF(3)SO(3))(2) and [Zn(2)L(2)(OH(2))(2)](CF(3)SO(3))(4) in buffered water (pH 7.4) at 25 degrees C show that the host strongly binds a series of phosphate derivatives. In comparison, the complex [CuL(3)(OH(2))(2)](CF(3)SO(3))(2) is a poor receptor toward phosphate substrates.
Collapse
Affiliation(s)
- Andrew C Benniston
- Molecular Photonics Laboratory, School of Natural Sciences (Chemistry), Bedson Building, University of Newcastle, Newcastle upon Tyne NE1 7RU, UK.
| | | | | |
Collapse
|
28
|
Kato M, Tanase T. Tetranuclear copper(II) complex with glucose-1-phosphate and its phosphate ester exchange with ATP. Inorg Chem 2005; 44:8-10. [PMID: 15627353 DOI: 10.1021/ic0487631] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The novel tetranuclear copper(II) complexes with alpha-d-glucose-1-phosphates, [Cu(4)(mu-OH)(alpha-d-Glc-1P)(2)(L)(4)(H(2)O)(2)](NO(3))(3) (L = bpy (1), phen (2)), were prepared and characterized by X-ray crystallography. Complex 1 was further transformed into the ATP stabilized tetracopper(II) complex of [Cu(4)(ATP)(2)(bpy)(4)] (4), where ATP is adenosine 5'-triphosphate.
Collapse
Affiliation(s)
- Merii Kato
- Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-higashi-machi, Nara 630-8285, Japan
| | | |
Collapse
|
29
|
Sah AK, Kato M, Tanase T. Trinuclear coordinatively labile Cu(ii) complex of 4,6-O-ethylidene-β-d-glucopyranosylamine derived Schiff base ligand and its reactivity towards primary alcohols and amines. Chem Commun (Camb) 2005:675-7. [PMID: 15672174 DOI: 10.1039/b413923b] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel neutral trinuclear Cu(II) complex of a Schiff base ligand derived from D-glucose has been synthesised and structurally characterised, which exhibits excellent alcohol binding affinity and activates the C-Cl bond of chloroform in the presence of primary amine.
Collapse
Affiliation(s)
- Ajay K Sah
- Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-higashi-machi, Nara 630-8285, Japan
| | | | | |
Collapse
|
30
|
Sah AK, Tanase T. Crystal-to-crystal transformation from tri- to mononuclear Cu(ii) complex with a sugar-derived ligand via proton transfer reaction and rearrangement of hydrogen bonding networks. Chem Commun (Camb) 2005:5980-1. [PMID: 16333500 DOI: 10.1039/b513788h] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Treatment of a glycosylamine derived Cu(II) complex with ethylamine resulted in crystal-to-crystal transformation from trinuclear complex [Cu3(L1)2(EtNH2)2(MeOH)2]x2MeOHxCHCl3 (2x2MeOHxCHCl3) to a dimeric structure of mononuclear complex [Cu(HL1)(EtNH2)] (3) through proton transfer reaction and rearrangement of hydrogen bonding networks.
Collapse
Affiliation(s)
- Ajay K Sah
- Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoya-higashi-machi, Nara, 630-8285, Japan
| | | |
Collapse
|
31
|
Storr T, Obata M, Fisher CL, Bayly SR, Green DE, Brudziñska I, Mikata Y, Patrick BO, Adam MJ, Yano S, Orvig C. Novel Carbohydrate-Appended Metal Complexes for Potential Use in Molecular Imaging. Chemistry 2004; 11:195-203. [PMID: 15540259 DOI: 10.1002/chem.200400719] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Seven discrete sugar-pendant diamines were complexed to the {M(CO)(3)}(+) ((99m)Tc/Re) core: 1,3-diamino-2-propyl beta-D-glucopyranoside (L(1)), 1,3-diamino-2-propyl beta-D-xylopyranoside (L(2)), 1,3-diamino-2-propyl alpha-D-mannopyranoside (L(3)), 1,3-diamino-2-propyl alpha-D-galactopyranoside (L(4)), 1,3-diamino-2-propyl beta-D-galactopyranoside (L(5)), 1,3-diamino-2-propyl beta-(alpha-D-glucopyranosyl-(1,4)-D-glucopyranoside) (L(6)), and bis(aminomethyl)bis[(beta-D-glucopyranosyloxy)methyl]methane (L(7)). The Re complexes [Re(L(1)-L(7))(Br)(CO)(3)] were characterized by (1)H and (13)C 1D/2D NMR spectroscopy which confirmed the pendant nature of the carbohydrate moieties in solution. Additional characterization was provided by IR spectroscopy, elemental analysis, and mass spectrometry. Two analogues, [Re(L(2))(CO)(3)Br] and [Re(L(3))(CO)(3)Br], were characterized in the solid state by X-ray crystallography and represent the first reported structures of Re organometallic carbohydrate compounds. Conductivity measurements in H(2)O established that the complexes exist as [Re(L(1)-L(7))(H(2)O)(CO)(3)]Br in aqueous conditions. Radiolabelling of L(1)-L(7) with [(99m)Tc(H(2)O)(3)(CO)(3)](+) afforded in high yield compounds of identical character to the Re analogues. The radiolabelled compounds were determined to exhibit high in vitro stability towards ligand exchange in the presence of an excess of either cysteine or histidine over a 24 h period.
Collapse
Affiliation(s)
- Tim Storr
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Affiliation(s)
- Gerard Parkin
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| |
Collapse
|
33
|
de Hoog P, Pachon LD, Gamez P, Lutz M, Spek AL, Reedijk J. Solution-stable trinuclear zinc(ii) cluster from 4-methyl-2-N-(2-pyridylmethylene)aminophenol (HPyrimol). Dalton Trans 2004:2614-5. [PMID: 15514742 DOI: 10.1039/b407637k] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of zinc(II) acetate with 4-methyl-2-N-(2-pyridylmethyl)aminophenol (HPyramol) in methanol leads to a solution stable linear trinuclear zinc cluster with intramolecular ligand oxidation.
Collapse
Affiliation(s)
- Paul de Hoog
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, The Netherlands
| | | | | | | | | | | |
Collapse
|
34
|
Tei L, Bencini A, Blake AJ, Lippolis V, Perra A, Valtancoli B, Wilson C, Schröder M. Co-ordination chemistry of amino pendant arm derivatives of 1,4,7-triazacyclononane. Dalton Trans 2004:1934-44. [PMID: 15252580 DOI: 10.1039/b404312j] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The binding properties of 1,4,7-triazacyclononane ([9]aneN3) to metal cations can be adapted through sequential functionalisation of the secondary amines with aminoethyl or aminopropyl pendant arms to generate ligands with increasing numbers of donor atoms. The new amino functionalised pendant arm derivative of 1,4,7-triazacyclononane ([9]aneN3), L1, has been synthesised and its salt [H2L1]Cl2 characterised by X-ray diffraction. The protonation constants of the ligands L1-L4 having one, two or three aminoethyl or three aminopropyl pendant arms, respectively, on the [9]aneN3 framework, and the thermodynamic stabilities of their mononuclear complexes with CuII and ZnII have been investigated by potentiometric measurements in aqueous solutions. In order to discern the protonation sites of ligands L1-L4, 1H NMR spectroscopic studies were performed in D2O as a function of pH. While the stability constants of the CuII complexes increase on going from L1 to L2 and then decrease on going from L2 to L3 and L4, those for ZnII complexes increase from L1 to L3 and then decrease for L4. The X-ray crystal structures of the complexes [Cu(L1)(Br)]Br, [Zn(L1)(NO3)]NO3, [Cu(L2)](ClO4)2, [Ni(L2)(MeCN)](BF4)2, [Zn(L4)](BF4)2.MeCN and [Mn(L4)](NO3)2.1/2H2O have been determined. In both [Cu(L1)(Br)]Br and [Zn(L1)(NO3)]NO3 the metal ion is five co-ordinate and bound by four N-donors of the macrocyclic ligand and by one of the two counter-anions. The crystal structures of [Cu(L2)](ClO4)2 and [Ni(L2)(MeCN)](BF4)2 show the metal centre in slightly distorted square-based pyramidal and octahedral geometry, respectively, with a MeCN molecule completing the co-ordination sphere around NiII in the latter. In both [Zn(L4)](BF4)2.MeCN and [Mn(L4)](NO3)2.1/2H2O the metal ion is bound by all six N-donors of the macrocyclic ligand in a distorted octahedral geometry. Interestingly, and in agreement with the solution studies and with the marked preference of CuII to assume a square-based pyramidal geometry with these types of ligands, the reaction of L4 with one equivalent of Cu(BF4)2.4H2O in MeOH at room temperature yields a square-based pyramidal five co-ordinate CuII complex [Cu(L6)](BF4)2 where one of the three propylamino pendant arms of the starting ligand has been cleaved to give L6.
Collapse
Affiliation(s)
- Lorenzo Tei
- Dipartimento di Chimica Inorganica ed analitica, University of Cagliari, Complesso Universitario di Monserrato, S. S. 554 Bivio per Sestu, 09042 (CA), Italy
| | | | | | | | | | | | | | | |
Collapse
|
35
|
|