- Homo- and heterobinuclear Cu2+ and Zn2+ complexes of abiotic cyclic hexaazapyridinocyclophanes as SOD mimics
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The new receptor 3,7,11,15,19,23-hexaaza-1(2,6)-pyridinacyclotetracosaphane (L1) containing a complete sequence of propylenic chains has been synthesised. The acid-base behaviour and Cu2+ and Zn2+ coordination have been analysed by p
- Belda, Raquel,Blasco, Salvador,Verdejo, Bego?a,Jiménez, Hermas R.,Doménech-Carbó, Antonio,Soriano, Conxa,Latorre, Julio,Terencio, Carmen,García-Espa?a, Enrique
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p. 11194 - 11204
(2013/08/23)
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- Intermolecular binding modes in a novel [1 + 1] condensation 1 H -pyrazole azamacrocycle: A solution and solid state study with evidence for CO2 fixation
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The synthesis of a novel cyclophane (L1) consisting of a 1H-pyrazole moiety linked through methylene groups to a 1,5,9,13-tetraazadecane chain is described. As far as we know, this is one of the first reported syntheses of a [1 + 1] condensation 1H-pyrazole azamacrocyclic ligand. The crystal structures of the complexes [Cu2(H(H-1L1))(H-1L1)] (ClO4)3·3.75H2O (1) and ([Cu 2(H(H-1L1))0.5(H-1L1) 1.5]2(ClO4)3Br2·4. 2H2O (2) show that Cu2+ coordination leads to formation of 2:2 Cu2+:L dinuclear dimeric complexes in which the 1H-pyrazole units lose a proton behaving as bis(monodentate) bridging ligands. Unlike previously reported complexes of [2 + 2] pyrazole azamacrocycles, the pyrazolate units in 1 are pointing outward from the macrocyclic cavity to bind the Cu 2+ ions. Inner coordination with formation of 1:1 Cu2+:L complexes is however observed in [1 + 1] pyridine azamacrocycles as shown by the crystal structure here presented of the complex [CuL2](ClO4) 2 (3). Crystals of [Cu3(H-1L1) 2(CO3)(H2O)](ClO4) 2·8H2O (4) grown by evaporating aqueous solution at pH 9 containing Cu2+ and L1 in 3:2 molar ratio show the presence of a further Cu2+ coordinated to the two free amine groups found in structures 1 and 2. The metal ion fills its coordination sphere capturing atmospheric CO2 as a η1,η2-bidentate carbonate anion placed in the equatorial position and an axial water molecule. pH-metric data, UV-vis spectroscopic data, EPR measurements, and HR-ESI-MS data support that the outer coordination mode with formation of 2:2 dinuclear dimeric and 3:2 trinuclear complexes is preserved in aqueous solution.
- Belda, Raquel,Pitarch-Jarque, Javier,Soriano, Conxa,Llinares, Jose M.,Blasco, Salvador,Ferrando-Soria, Jesus,Garcia-Espana, Enrique
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p. 10795 - 10803
(2013/10/22)
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- A convenient modified short route for the preparation of [32]ane-N 8 hydrochloride
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A conve nient modified short-cut route for the prep a ration of a 32-membered octaazamacrocyclic mol ecule, 1,5,9,13,17,21,25,29- octaazacyclodotriacontane hydrochlo ride, [32]ane-N8·8HCl has been de scribed. The proper tetramine has been con t
- Misra, Tarun Kumar,Chen, Tse-Shien,Wong, Ken-Tsung,Liu, Chuen-Ying
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p. 793 - 797
(2007/10/03)
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- Synthesis and characterization of various unsubstituted and mono-N-substituted tetraazamacrocycles
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Syntheses of tetraazamacrocycles have been carried out by using p-toluenesulfonyl chloride as protective group.The and were also obtained by the template synthesis.Mono-N-functionalization of tetraazamacrocycles was accomplished by reaction of a fivefold excess of the free macrocycles with 1 equivalent of a suitable alkylating or arylating reagent.The key point of the synthesis lies in the use of an excess of the macrocycle over the substituting reactants to reduce the formation of polysubstituted derivatives, and in the easy separation of the excess of unreacted macrocycle.All the products were characterized on the basis of spectral studies (1H and 13C NMR, including 2D NMR and NOE difference studies) and mass spectrometry.Key words: tetraazamacrocycles, improved synthesis, protective group, N-tosylation, template synthesis, NOE difference spectroscopy.
- Meunier, I.,Mishra, A. K.,Hanquet, B.,Cocolios, P.,Guilard, R.
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p. 685 - 695
(2007/10/02)
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- Design and Synthesis of Macromonocyclic Polyamines Composed of Natural Methylene Arrays
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A general synthetic method applicable to acyclic and cyclic polyamines was developed.The methodology was exemplified by systematical synthesis of twelve macromonocyclic polyamines, 1 (N4) through 12 (N8), composed of the combination of four natural polyamine segments, spermidine, spermine, thermine, and thermospermine.These twelve designed macrocycles are exhausted numbers of possible structures defined by three arbitrarily chosen criteria concerning with methylene chain arrays and nitrogen content (four to eight).The common elements of the structural characteristics were analyzed and were found to be reduced to readily available three classes of simple N,N'-ditosylalkanediamines derived from diamines and triamine.Nitrogen content was increased systematically through the reaction of N,N'-ditosylalkanediamine with one of three ω-phthalimidated electrophiles followed by regeneration of the same functionality at symmetrical both terminals as the starting materials via a series of transformation reaction, in excellent yields.Tractable formamide intermediate profits the facile synthesis of acyclic polyamines with long chains.Cyclization was achieved, under high dilution conditions, through the reaction of α,ω-bis(tosylamide) with α,ω-ditosylates in DMF in the presence of cesium carbonate.The cyclization occurred in practical synthetic yields even in the formation of multi-membered ring when the shorter electrophile and the longest α,ω-bis(tosylamide) reacted.
- Iwata, Masaaki,Kuzuhara, Hiroyoshi
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p. 198 - 210
(2007/10/02)
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- 123. Synthesis and Protonation Features of 24-, 27- and 32-membered Macrocyclic Polyamines
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Three macrocyclic polyamines ane-N6 1, ane-N8 2 and ane-N6O3 3 of ring size 24, 32 and 27, respectively, have been synthesized.They contain either trimethylenediamine of ethylenediamine units.The acyclic analog 4, as the reference compound, wa
- Dietrich, Bernard,Hosseini, Mir Wais,Lehn, Jean-Marie,Sessions, Richard B.
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p. 1262 - 1278
(2007/10/02)
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- TETRAAZAMACROCYCLES LIPOPHILES: SYNTHESE ET APPLICATION A L'EXTRACTION DE Cu(II), Cd(II) et Pb(II)
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The synthesis of three lipophilic n-dodecyl tetraazacycloalkenes is descricribed.Extraction of Cu(II), Cd(II) and Pb(II) is related.
- Muller, Frederic R.,Handel, Henri
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p. 2769 - 2772
(2007/10/02)
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