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1.

001-es BibID:BIBFORM085254
Első szerző:Andersson, Ingegärd
Cím:Speciation in the aqueous H+/H2VO4?/H2O2/phosphate system / Ingegärd Andersson, András Gorzsás; Csaba Kerezsi, Imre Tóth, Lage Pettersson
Dátum:2005
ISSN:1477-9226
Megjegyzések:The speciation in the aqueous H+/H2VO4?/phosphate (dihydrogen phosphate, P?) and H+/H2VO4?/H2O2/P? systems has been determined in the physiological medium of 0.150 M Na(Cl) at 25 °C. A combination of multinuclear NMR integral and chemical shift (Bruker AMX500) as well as potentiometric data (glass electrode) have been collected and treated simultaneously by the computer program LAKE. The pKa-values for phosphoric acid have been determined by potentiometric and 31P NMR chemical shift data, and have been found to be 1.85 ± 0.02, 6.69 ± 0.02 and 11.58 ± 0.07. The errors given are 3?. Altogether nine vanadate-phosphate species have been found in the ternary H+/H2VO4?/P? system in the pH region 1-11, with the following compositions: VP, VP2 and V14P. Equilibrium is very slow in acidic solutions, requiring more than 3 months for the formation of V14P species. On the other hand, less than 15 min are needed for equilibration at neutral and alkaline pH. In the quaternary H+/H2VO4?/H2O2/P? system, four new species have been found in addition to all binary and ternary complexes. They are of VXP and VX2P compositions, where X denotes the peroxo ligand. 51V and 31P NMR chemical shifts, compositions and formation constants are given, and equilibrium conditions are illustrated in distribution diagrams as well as the fit of the model to the experimental data. Biological and medical relevance of the species is also discussed and physiological conditions are modelled.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Dalton Transactions. - 22 (2005), p. 3658-3666. -
További szerzők:Gorzsás András Kerezsi Csaba Tóth Imre (1950-) (vegyész) Pettersson, Lage
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2.

001-es BibID:BIBFORM136817
035-os BibID:(WoS)001724587800001
Első szerző:Balogh Bettina Diána (vegyész)
Cím:How do copper(II) and zinc(II) bind to tau protein, and how might this promote aggregation? / Bettina Diána Balogh, Giuseppe Di Natale, Giuseppe Pappalardo, Katalin Várnagy
Dátum:2026
ISSN:1477-9226
Megjegyzések:Neurodegenerative tauopathies are characterized by extracellular protein deposits of amyloid-β and the intracellular aggregates of hyperphosphorylated tau in the brain. A great number of publications support that essential metal ions (such as zinc and copper) play an important role in the development of neurodegeneration. The histidine imidazole rings are frequent metal binding sites in proteins, and tau is relatively rich in this moiety. The 12 histidyl residues of the protein are well separated and can be found in different chemical environments; hence, their metal binding properties differ, at least slightly. The comparison of the metal binding affinity of the His32 moiety from the N-terminal part of tau with that of the His329- His330 residues from the R3 domain revealed that His32 is a more favourable binding site for copper(II) ions than the adjacent histidine residues in neutral medium, while the His329-His330 moieties provide a binding site for zinc(II) ions at physiological pH. To further elucidate the metal binding ability of His32 and His329-His330, we studied the complex formation processes of a chimeric peptide (AcTMHQDNIHHKP-NH2) that contains the 30-34 residues (TMHQD) linked to the 327-332 residues (NIHHKP) in a single molecule (tau(30-34)(327-332)). The pH potentiometric, spectroscopic (UV-Vis and CD) and mass spectrometry studies on the copper(II) complexes of the peptide revealed that in equimolar samples, predominantly mononuclear complexes with 1 : 1 stoichiometry are formed. At physiological pH and in alkaline samples, the His32 imidazole nitrogen becomes the main, albeit not exclusive, anchoring group. The coordination mode of these copper(II) complexes involves imidazole-N donor atoms and deprotonated amide functions. In the presence of zinc(II) ions, only mononuclear species are formed. The results obtained for the mixed copper(II)-zinc(II) complexes indicate that the N-terminal imidazole nitrogen (His32) is the main anchoring group for copper(II) ions, while zinc(II) is accumulated at one of the adjacent histidyl residues if both metal ions are present in the solution at physiological pH. These findings are in agreement with the hypothesis that zinc(II), by binding to the R3 region, aggravates the aggregation processes of the R3 region and may increase the tau`s toxicity.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Dalton Transactions. - 55 : 14 (2026), p. 5788-5804. -
További szerzők:Di Natale, Giuseppe Pappalardo, Giuseppe Várnagy Katalin (1961-) (vegyész)
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3.

001-es BibID:BIBFORM103968
035-os BibID:(WoS)000700168000001 (Scopus)85117440520
Első szerző:Balogh Bettina Diána (vegyész)
Cím:Thermodynamics and structural characterization of the nickel(II) and zinc(II) complexes of various peptide fragments of tau protein / Balogh Bettina Diána, Szunyog Györgyi, Lukács Márton, Szakács Bence, Sóvágó Imre, Várnagy Katalin
Dátum:2021
ISSN:1477-9226
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Dalton Transactions. - 50 : 40 (2021), p. 14411-14420. -
További szerzők:Szunyog Györgyi (1991-) (okleveles vegyész) Lukács Márton (1992-) (vegyész) Szakács Bence (1996-) (vegyész) Sóvágó Imre (1946-) (vegyész) Várnagy Katalin (1961-) (vegyész)
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4.

001-es BibID:BIBFORM067207
Első szerző:Baranyai Zsolt (vegyész)
Cím:A shortcut to high-affinity Ga-68 and Cu-64 radiopharmaceuticals : one-pot click chemistry trimerisation on the TRAP platform / Zsolt Baranyai, Dominik Reich, Adrienn Vágner, Martina Weineisen, Imre Tóth, Hans-Jürgen Wester, Johannes Notni
Dátum:2015
ISSN:1477-9226
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Dalton Transactions. - 44 : 24 (2015), p. 11137-11146. -
További szerzők:Reich, Dominik Vágner Adrienn (1990-) (vegyész, kémikus) Weineisen, Martina Tóth Imre (1950-) (vegyész) Wester, Hans J. Notni, Johannes
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5.

001-es BibID:BIBFORM030848
Első szerző:Bíró Linda (vegyész)
Cím:Hydrolytic behaviour and chloride ion binding capability of [Ru(n6-p-cym)(H2O)3]2+ : a solution equilibrium study / Linda Bíró, Etelka Farkas, Péter Buglyó
Dátum:2012
ISSN:1477-9226
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Dalton Transactions. - 41 : 1 (2012), p. 285-291. -
További szerzők:Farkas Etelka (1948-) (vegyész) Buglyó Péter (1965-) (vegyész)
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6.

001-es BibID:BIBFORM016457
Első szerző:Bíró Linda (vegyész)
Cím:Complex formation between Ru(eta(6)-p-cym)(H2O)(3) (2+) and (O,O) donor ligands with biological relevance in aqueous solution / Linda Bíró, Etelka Farkas, Péter Buglyó
Dátum:2010
ISSN:1477-9226
Megjegyzések:The interaction between [Ru(eta(6)-p-cym)(H2O)(3)](2+) and (O,O) type chelators with different basicity of the donor atoms was studied using combined pH-potentiometric, H-1-NMR and ESI-TOF-MS techniques. The studied nine ligands are building blocks of reported complexes with antitumor activity or may model (O, O) donor serum components capable of interacting with the administered half-sandwich ruthenium(II) type drug. Composition and stability constants of the [Ru(eta(6)-p-cym)(O,O)Y] type species (Y: H2O or OH-) were determined (T = 25.0 degrees C; I = 0.20 M (KCl)) and the metal ion binding strengths of the ligands are discussed. It was found that ligands with two low basicity O donors (oxalic and cyclobutane-1,1-dicarboxylic acid) bind the metal ion at acidic conditions but are not able to prevent the hydrolysis at physiologically relevant conditions. Ligands with one low and one high basicity O donor (lactic and salicylic acid) are weak binders for Ru(eta(6)-p-cym)(H2O)(3)](2+). Pyrone or pyridinone based ligands are capable of binding the metal ion over a wide pH range and no hydrolysis product is detectable at pH = 7.4. The obtained speciation models may help in the rationalization of the biological activity of such complexes and provide a deeper insight into the solution behaviour of half-sandwich Ru(II) complexes with potential anticancer activity.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
anticancer complexes
derivatives
ruthenium
hydrolysis
catechol
serum
Megjelenés:Dalton Transactions. - 39 : 42 (2010), p. 10272-10278. -
További szerzők:Farkas Etelka (1948-) (vegyész) Buglyó Péter (1965-) (vegyész)
Pályázati támogatás:K76142
OTKA
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7.

001-es BibID:BIBFORM117863
035-os BibID:(WOS)001137891900001 (Scopus)85181518337
Első szerző:Bonczidai-Kelemen Dóra
Cím:The role of the terminal cysteine moiety in a metallopeptide mimicking the active site of the NiSOD enzyme / Dóra Bonczidai-Kelemen, Klaudia Tóth, István Fábián, Norbert Lihi
Dátum:2024
ISSN:1477-9226
Megjegyzések:Superoxide dismutase (SOD) enzymes are pivotal in regulating oxidative stress. In order to model Ni containing SOD enzymes, the results of the thermodynamic, spectroscopic and SOD activity studies on the complexes formed between nickel(ii) and a NiSOD related peptide, CysCysAspLeuProCysGlyValTyr-NH2 (wtCC), are reported. Cysteine was introduced to replace the first histidine residue in the amino acid sequence of the active site of the NiSOD enzyme. The novel peptide exhibits 3 times higher metal binding affinity compared to the native NiSOD fragment. This is due to the presence of the first cysteine in the coordination sphere of nickel(ii). At physiological pH, the (NH2,S-,S-,S-) coordinated complex is the major species. This coordination mode is altered when one thiolate group is replaced by an amide nitrogen of the peptide backbone above pH 7.5. The nickel complexes of wtCC exhibit similar SOD activity to that of the complex formed with the active site fragment of the native NiSOD. The reaction between the complexes and the superoxide anion was studied by the sequential stopped-flow method. These studies revealed that the nickel(ii) complex is always in excess over the nickel(iii) complex during the dismutation process. However, the nickel(iii) species is also involved in a relatively fast degradation process. This unambiguously proves that a protective mechanism must be operative in the NiSOD enzyme which prevents the oxidation of the sulfur atom of cysteine in the presence of O2?. The results provide new possibilities for the use of NiSOD mimics in bio- and industrial catalytic processes.
Tárgyszavak:Természettudományok Kémiai tudományok magyar nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Amino acids
Binding energy
Coordination reactions
Nickel compounds
Peptides
pH
Superoxide dismutase
Active site
Amino acid sequence
Histidine residues
Metallopeptides
Ni-containing superoxide dismutase
Nickel complex
Super oxide dismutase
Superoxide dismutase activities
Superoxide dismutases
Terminal cysteine
Amides
Megjelenés:Dalton Transactions. - 53 : 4 (2024), p. 1648-1656. -
További szerzők:Tóth Klaudia (1998-) (általános orvos) Fábián István (1956-) (vegyész) Lihi Norbert (1990-) (vegyész)
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8.

001-es BibID:BIBFORM016458
Első szerző:Budimir, Ana
Cím:Water exchange rates of water-soluble manganese(III) porphyrins of therapeutical potential / Ana Budimir, József Kalmár, István Fábián, Gábor Lente, István Bányai, Ines Batinić-Haberle, Mladen Biruš
Dátum:2010
ISSN:1477-9226
Megjegyzések:The activation parameters and the rate constants of the water-exchange reactions of (MnTE)-T-III-2-PyP5+ (meso-tetrakis(N-ethylpyridinium-2-yl) porphyrin) as cationic, Mn(III)TnHex-2-PyP5+ (meso-tetrakis(N-n-hexylpyridinium-2-yl) porphyrin) as sterically shielded cationic, and (MnTSPP3-)-T-III (meso-tetrakis(4-sulfonatophenyl) porphyrin) as anionic manganese(III) porphyrins were determined from the temperature dependence of O-17 NMR relaxation rates. The rate constants at 298 K were obtained as 4.12 x 10(6) s(-1), 5.73 x 10(6) s(-1), and 2.74 x 10(7) s(-1), respectively. On the basis of the determined entropies of activation, an interchange-dissociative mechanism (I-d) was proposed for the cationic complexes (Delta double dagger S = similar to 0 J mol(-1) K-1) whereas a limiting dissociative mechanism (D) was proposed for (MnTSPP3-)-T-III complex (Delta S double dagger = + 79 J mol(-1) K-1). The obtained water exchange rate of (MnTSPP3-)-T-III corresponded well to the previously assumed value used by Koenig et al. (S. H. Koenig, R. D. Brown and M. Spiller, Magn. Reson. Med., 1987, 4, 52-260) to simulate the H-1 NMRD curves, therefore the measured value supports the theory developed for explaining the anomalous relaxivity of (MnTSPP3-)-T-III complex. A magnitude of the obtained water-exchange rate constants further confirms the suggested inner sphere electron transfer mechanism for the reactions of the two positively charged Mn(III) porphyrins with the various biologically important oxygen and nitrogen reactive species. Due to the high biological and clinical relevance of the reactions that occur at the metal site of the studied Mn(III) porphyrins, the determination of water exchange rates advanced our insight into their efficacy and mechanism of action, and in turn should impact their further development for both diagnostic (imaging) and therapeutic purposes.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
superoxide-dismutase activity
deficient escherichia-coli
nuclear
magnetic-resonance
iron(iii) porphyrins
oxidative stress
redox
modulation
contrast-media
mechanism
relaxation
complexes
Megjelenés:Dalton Transactions. - 39 (2010), p. 4405-4410. -
További szerzők:Kalmár József (1985-) (vegyész) Fábián István (1956-) (vegyész) Lente Gábor (1973-) (vegyész) Bányai István (1953-) (vegyész) Batinić-Haberle, Ines Biruš, Mladen
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9.

001-es BibID:BIBFORM086035
Első szerző:Buglyó Péter (vegyész)
Cím:Interaction between the low molecular mass components of blood serum and the VO(iv)-DHP system (DHP = 1,2-dimethyl-3-hydroxy-4(1H)-pyridinone) / Péter Buglyó, Tamás Kiss, Erzsébet Kiss, Daniele Sanna, Eugenio Garribba, Giovanni Micera
Dátum:2002
ISSN:0300-9246 1364-5447
Megjegyzések:In order to estimate the impact of the low molecular mass (l.m.m.) VO(IV) binders of blood serum on the potentially insulin-enhancing drug [VO(DHP)(2)] [DHP=1,2-dimethyl-3-hydroxy-4(1H)-pyridinone], the speciation in the binary system VO(IV)-DHP and in the ternary systems VO-DHP-ligand B (B=oxalate, lactate, citrate or phosphate) was studied by pH-potentiometry at 25.0degreesC and at an ionic strength I=0.2 mol dm(-3) (KCl). The binding modes of the complexes formed were determined by spectroscopic (electronic absorption and EPR) techniques. DHP was found to form stable mono and bis complexes via the coordination of (O,O) chelate(s). Through displacement of the oxo group of VO(), the tris complex is also formed, especially at a high excess of ligand. The results in the ternary systems demonstrate that, at physiological pH, none of the B ligands can compete with DHP; [VO(DHP)(2)] therefore seems to remain almost completely intact, even in the presence of citrate, the strongest competitor among these B ligands. These findings indicate that, for DHP, unlike maltol or picolinic acid, ternary complex formation and thus transformation reactions with the l.m.m. binders of biofluids, is almost negligible. From among the three carrier molecules, only DHP can efficiently compete with serum transferrin for binding of VO(IV).
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Journal of the Chemical Society. Dalton Transactions. - 11 (2002), p. 2275-2282. -
További szerzők:Kiss Tamás (1950-) (vegyész) Kiss Erzsébet (vegyész) Sanna, Daniele (1956-) (vegyész) Garribba, Eugenio Micera, Giovanni
Pályázati támogatás:T31896
OTKA
F32235
OTKA
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10.

001-es BibID:BIBFORM010511
Első szerző:Buglyó Péter (vegyész)
Cím:Novel half-sandwich Ru(II)-hydroxamate complexes : synthesis, characterization and equilibrium study in aqueous solution / Péter Buglyó, Etelka Farkas
Dátum:2009
ISSN:1477-9226
Megjegyzések:Novel half-sandwich Ru(II)-benzohydroxamate complexes were synthesized. [Ru(eta(6)-p-cymene)(mu-bha)](2)Cl-2 (bhaH = benzohydroxamic acid) with (O,O) coordination of the ligand, was characterized by elemental analysis, spectroscopic (H-1-NMR, IR) and ESI-MS methods. Replacement of the chloride of the precursor by CF3SO3- and reaction of the obtained [Ru(eta(6)-p-cym)(acetone)(3)](CF3SO3)(2) with bhaH affords [Ru(eta(6)-p-cymene)(mu-bha)](2)(CF3SO3)(2), the crystal and molecular structure of which has been determined by X-ray crystallography. In this complex, the first reported structure of an organometallic Ru(II)-hydroxamate, the carbonyl oxygens of the bha ligands coordinate to one of the Ru units and the hydroxamate oxygens bridge the two Ru atoms. Hydrolytic behaviour of [Ru(eta(6)-p-cym)Cl-x(H2O)(3-x)]((2-x)+) (x = 0-3) present in aqueous solution and its complex forming capabilities with N-methyl-acetohydroxamic acid (meahaH) were studied by pH-potentiometric, H-1-NMR, UV-Vis and ESI-MS methods. Formation constants of the various species present in solution are reported. The data are consistent with the formation of the stable, monomeric [Ru(eta(6)-p-cym)(meaha)](+) as the major species at physiological pH.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Dalton Transactions. - 38 (2009), p. 8063-8070. -
További szerzők:Farkas Etelka (1948-) (vegyész)
Pályázati támogatás:K76142
OTKA
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11.

001-es BibID:BIBFORM116497
035-os BibID:(WoS)001101303500001 (Scopus)85176281648
Első szerző:Bunda Szilvia (vegyész)
Cím:Bipyridil-based chelators for Gd(III) complexation: kinetic, structural and relaxation properties / Szilvia Bunda, Norbert Lihi, Zsófia Szaniszló, David Esteban-Gómez, Carlos Platas-Iglesias, Mónika Kéri, Gábor Papp, Ferenc Krisztián Kálmán
Dátum:2023
ISSN:1477-9226
Megjegyzések:In the last 20 years, research in the field of MRI (magnetic resonance imaging) contrast agents (CAs) has been intensified due to the emergence of a disease called nephrogenic systemic fibrosis (NSF). NSF has been linked to the in vivo dissociation of certain Gd(III)-based compounds applied in MRI as CAs. To prevent the dechelation of the probes after intravenous injection, the improvement of their in vivo stability is highly desired. The inertness of the Gd(III) chelates can be increased through the rigidification of the ligand structure. One of the potential ligands is (2,2 ',2 '',2 '''-(([2,2 '-bipyridine]-6,6 '-diylbis(methylene))bis(azanetriyl))tetraacetic acid) (H(4)DIPTA), which has been successfully used as a fluorescent probe for lanthanides; however, it has never been considered as a potential chelator for Gd(III) ions. In this paper, we report the thermodynamic, kinetic and structural features of the complex formed between Gd(III) and DIPTA. Since the solubility of the [Gd(DIPTA)](-) chelate is very low under acidic conditions, hampering its thermodynamic characterization, we can only assume that its stability is close to that determined for the structural analogue [Gd(FENTA)](-) (H(4)FENTA: (1,10-phenanthroline-2,9-diyl)bis(methyliminodiacetic acid)), which is similar to that determined for the agent [Gd(DTPA)](2-) routinely used in clinical practice. Unfortunately, the inertness of [Gd(DIPTA)](-) is significantly lower (t(1/2) = 1.34 h) than that observed for [Gd(EGTA)](-) and [Gd(DTPA)](2-) as a result of its spontaneous dissociation pathway during dechelation. The relaxivity values of [Gd(DIPTA)](-) are comparable with those of [Gd(FENTA)](-) and somewhat higher than the values characterizing [Gd(DTPA)](2-). Luminescence lifetime measurements indicate the presence of one water molecule (q = 1) in the inner sphere of the complex with a relatively high water exchange rate (k(ex)(298) = 43(5) x 10(6) s(-1)). DFT calculations suggest a rigid distorted tricapped trigonal prismatic polyhedron for the Gd(III) complex. On the basis of these results, we can conclude that the bipyridine backbone is not favourable with respect to the inertness of the chelate.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
koordinációs kémia
Gd(III)-komplex
kinetika
relaxivitás
Megjelenés:Dalton Transactions. - 52 : 45 (2023), p. 17030-17040. -
További szerzők:Lihi Norbert (1990-) (vegyész) Szaniszló Zsófia (1998-) (vegyészmérnök) Esteban-Gómez, David Platas-Iglesias, Carlos Kéri Mónika (1984-) (környezetkutató vegyész) Papp Gábor (1976-) (vegyész, kémikus) Kálmán Ferenc K. (1978-) (vegyész)
Pályázati támogatás:FK-134551
OTKA
2019-2.1.11-TET-2019-00084
Egyéb
ÚNKP-22-5
Egyéb
ÚNKP-23-5
Egyéb
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12.

001-es BibID:BIBFORM084830
Első szerző:Csajbók Éva (vegyész, kémikus)
Cím:Dynamic NMR properties of DOTA ligand: variable pH and temperature 1H NMR study on [K(HxDOTA)](3-x)- species / Éva Csajbók, István Bányai, Ernő Brücher
Dátum:2004
ISSN:1477-9226
Megjegyzések:The (1)H NMR spectra of [H(x)DOTA]((4-x)-) species are reported as a function of pH and temperature in aqueous solution. The spectra show line broadening both in ligand proton signals and also in the water proton signal by titration with KOH solution. The formation of different [K(H(x)DOTA)]((3-x)-) complexes is found to be responsible for this behaviour. At high pH the usual fluxional motions, i.e. the ring inversion and the change in the acetate arms' helicity, which are also characteristic for other but inert metal-DOTA complexes, have been detected. However, because of the kinetic lability of K(+)-O and K(+)-N coordinative bonds a new type of rearrangement appears. This new motion requires breaking of coordinative bonds in the complex and can be described as a certain type of "ring slewing" around the ring C-C bonds. At low temperature (about 270 K) the ring slewing slows down and becomes negligible compared with the ring inversion and the change in the arms' helicity. These two latter processes have the same rate. When the temperature is higher (about 320 K) the ring slewing accelerates and its rate exceeds the rate of ring inversion. At this temperature the change in the acetate arms' helicity has the same rate as the ring slewing. Additionally, in the pH range 4-5 a slow intermolecular proton exchange process has been observed between the water and the dissociable protons of [K(H(x)DOTA)]((3-x)-). A water-assisted proton exchange mechanism is proposed on the basis of the activation parameters. This finding supports the previously suggested slow proton motion hypothesis for the formation of DOTA complexes.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Dalton Transactions. - 2004 : 14 (2004), p. 2152-2156. -
További szerzők:Bányai István (1953-) (vegyész) Brücher Ernő (1935-) (vegyész)
Pályázati támogatás:OTKA T035127
OTKA
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
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