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Martinelli J, Romano E, Laczovics A, Horváth D, Grattoni E, Baranyai Z, Tei L. Improving the Stability and Kinetic Inertness of Mn(II) Complexes by Increasing the Bridge Length in Bicyclic CDTA-Like Ligands. Chemistry 2024; 30:e202400570. [PMID: 38597334 DOI: 10.1002/chem.202400570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 04/08/2024] [Accepted: 04/10/2024] [Indexed: 04/11/2024]
Abstract
Kinetic inertness of Mn(II)-based MRI contrast agents can be improved by increasing the rigidity of the polydentate ligand that tightly coordinate the metal ion. Taking inspiration from the remarkable increase in kinetic inertness of [Mn(CDTA)]2- compared to [Mn(EDTA)]2- due to the cyclohexyl backbone rigidity, we devised that bicyclic ligands would further improve the kinetic inertness of the Mn(II) complexes. The length of the alkyl bridge on the cyclohexane ring was varied from methylene (BCH-DTA), ethylene (BCO-DTA) to propylene (BCN-DTA) to evaluate the influence of the different trans-diaminotetraacetate ligands on relaxometric, thermodynamic and kinetic properties of the Mn(II) complexes. 1H and 17O NMR relaxometric studies showed a slight increase in relaxivity and a faster water exchange rate in these Mn(II)-complexes with respect to [Mn(CDTA)]2-. Solution studies revealed that the conditional stability (pMn) and dissociation half-life (t1/2) at pH 7.4 follow the order [Mn(BCH-DTA)]2-<[Mn(BCO-DTA)]2-<[Mn(BCN-DTA)]2- highlighting the effect of the bridge length on the overall stability of the Mn(II) complexes. Remarkably, [Mn(BCN-DTA)]2- shows an improved pMn value and a 7-times higher kinetic inertness than [Mn(CDTA)]2-. NMR studies on the Zn(II) analogues confirm the rigidity of the bicyclic complexes with an isomerization process at >313 K for the smaller bridged complex [Zn(BCH-DTA)]2-.
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Affiliation(s)
- Jonathan Martinelli
- Department of Science and Technological Innovation, University of Piemonte Orientale, Viale Teresa Michel 11, 15121, Alessandria, Italy
- Department of Health Sciences (DISSAL), Università di Genova, Via A. Pastore 1, 16132, Genova, Italy
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Largo R. Benzi 10, 16132, Genova, Italy
| | - Elisabetta Romano
- Department of Science and Technological Innovation, University of Piemonte Orientale, Viale Teresa Michel 11, 15121, Alessandria, Italy
| | - Attila Laczovics
- Faculty of Medicine, Institute of Medical Imaging, University of Debrecen, Nagyerdei körút 98, 4032, Debrecen, Hungary
| | - David Horváth
- Faculty of Science and Technology, Department of Physical Chemistry, Doctoral School of Chemistry, University of Debrecen, Egyetem tér 1, 4010, Debrecen, Hungary
- Bracco Imaging SpA, CRB Trieste, AREA Science Park, 34149, Basovizza (TS), Italy
| | - Elena Grattoni
- Bracco Imaging SpA, CRB Trieste, AREA Science Park, 34149, Basovizza (TS), Italy
- Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Trieste, Piazzale Europa 1, 34127, Trieste (TS), Italy
| | - Zsolt Baranyai
- Bracco Imaging SpA, CRB Trieste, AREA Science Park, 34149, Basovizza (TS), Italy
- Faculty of Science and Technology, Doctoral School of Chemistry, University of Debrecen, Egyetem tér 1, 4010, Debrecen, Hungary
| | - Lorenzo Tei
- Department of Science and Technological Innovation, University of Piemonte Orientale, Viale Teresa Michel 11, 15121, Alessandria, Italy
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Zapolotsky EN, Babailov SP, Fomin ES. STUDY OF THE STRUCTURE AND PARAMAGNETIC PROPERTIES OF THE [Dy(H2O)n(CyDTA)]– COMPLEX IN AN AQUEOUS SOLUTION USING NMR DATA. J STRUCT CHEM+ 2022. [DOI: 10.1134/s0022476622110142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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3
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Zapolotsky EN, Babailov SP. Conformational Dynamics and Thermosensory Properties of [Ln(H2O)n(EDTA)]– (Ln = Pr, Eu, Tb, Ho, Er, Tm) Complexes in Aqueous Solutions According to NMR Data. RUSS J INORG CHEM+ 2022. [DOI: 10.1134/s0036023622601064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Uzal-Varela R, Pérez-Fernández F, Valencia L, Rodríguez-Rodríguez A, Platas-Iglesias C, Caravan P, Esteban-Gómez D. Thermodynamic Stability of Mn(II) Complexes with Aminocarboxylate Ligands Analyzed Using Structural Descriptors. Inorg Chem 2022; 61:14173-14186. [PMID: 35994514 PMCID: PMC9455602 DOI: 10.1021/acs.inorgchem.2c02364] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
We present a quantitative analysis of the thermodynamic
stabilities
of Mn(II) complexes, defined by the equilibrium constants (log KMnL values) and the values of pMn obtained as
−log[Mn]free for total metal and ligand concentrations
of 1 and 10 μM, respectively. We used structural descriptors
to analyze the contributions to complex stability of different structural
motifs in a quantitative way. The experimental log KMnL and pMn values can be predicted to a good accuracy
by adding the contributions of the different motifs present in the
ligand structure. This allowed for the identification of features
that provide larger contributions to complex stability, which will
be very helpful for the design of efficient chelators for Mn(II) complexation.
This issue is particularly important to develop Mn(II) complexes for
medical applications, for instance, as magnetic resonance imaging
(MRI) contrast agents. The analysis performed here also indicates
that coordination number eight is more common for Mn(II) than is generally
assumed, with the highest log KMnL values generally observed for hepta- and octadentate ligands. The
X-ray crystal structure of [Mn2(DOTA)(H2O)2], in which eight-coordinate [Mn(DOTA)]2– units are bridged by six-coordinate exocyclic Mn(II) ions, is also
reported. We present empirical relationships
that allow estimating
the log K and pMn values of Mn(II) complexes
relevant as contrast agents for magnetic resonance imaging (MRI).
The prediction of complex stability with these expressions relies
on structural descriptors, providing a very powerful tool to aid with
ligand design.
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Affiliation(s)
- Rocío Uzal-Varela
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Francisco Pérez-Fernández
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Laura Valencia
- Departamento de Química Inorgánica, Facultad de Ciencias, Universidade de Vigo, As Lagoas, Marcosende, 36310 Pontevedra, Spain
| | - Aurora Rodríguez-Rodríguez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Peter Caravan
- The Institute for Innovation in Imaging and the A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 149, 13th Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
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Zapolotsky EN, Qu Y, Babailov SP. Lanthanide complexes with polyaminopolycarboxylates as prospective NMR/MRI diagnostic probes: peculiarities of molecular structure, dynamics and paramagnetic properties. J INCL PHENOM MACRO 2021; 102:1-33. [PMID: 34785985 PMCID: PMC8582344 DOI: 10.1007/s10847-021-01112-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 10/05/2021] [Indexed: 11/29/2022]
Abstract
The paramagnetic lanthanide complexes with polyaminopolycarboxylate (PAPC) ligands attract considerable attention from the standpoint of potential applications thereof as relaxation agents used in medical magnetic resonance imaging (MRI) and in luminescent materials, as well as owing to promising use thereof as paramagnetic labels for studying the properties of biopolymers since they exhibit thermodynamic stability, good solubility in aqueous media and moderate toxicity. For the last decades, the NMR methods have been used to determine the physical and chemical properties of paramagnetic Ln compounds. The studies concerning paramagnetic NMR lanthanide-induced shifts (LISs) in dissolved Ln complexes, as well as the analysis of band shape as a function of temperature make it possible to obtain valuable information on the structure, intra- and intermolecular dynamics and paramagnetic properties thereof. This review is devoted solely to the following features: firstly, the processes of intramolecular dynamics of lanthanide complexes with polyamino-polycarboxylate ligands such as DOTA, EDTA and DTPA and their derivatives studied by NMR; secondly, the LISs of lanthanide complexes with EDTA, DOTA, DTPA and some of their derivatives depending on temperature and pH. Moreover, in this review, for the first time, the dependence of the activation energy of molecular dynamics in complexes with polydentate ligands on the atomic number of the lanthanide cation is analyzed and a monotonic change in energy is detected, which is due to the effect of lanthanide contraction. It should be noted that this phenomenon is quite general and may also appear in the future in many other series of lanthanide complexes with both other multidentate ligands and with bidentate and monodentate ligands. In the future, it is possible to predict the dependence of the properties of certain lanthanide complexes on the ionic radius of the lanthanide cation based on the approaches presented in the review. In this review, we have also presented the dynamic NMR as the main research method widely used to analyze the processes of molecular dynamics, and the structural studies based on the NMR relaxation spectroscopy and LIS analysis.
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Affiliation(s)
- Eugeny N. Zapolotsky
- A.V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Av. Lavrentyev 3, Novosibirsk, Russia 630090
| | - Yanyang Qu
- Institute of Chemical Materials, CAEP, P. O. Box 919-311, Mianyang, 621900 Sichun China
| | - Sergey P. Babailov
- A.V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Av. Lavrentyev 3, Novosibirsk, Russia 630090
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Reaction mechanisms relevant to the formation and utilization of [Ru(edta)(NO)] complexes in aqueous media. J Inorg Biochem 2021; 225:111595. [PMID: 34555599 DOI: 10.1016/j.jinorgbio.2021.111595] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/13/2021] [Accepted: 08/27/2021] [Indexed: 12/11/2022]
Abstract
The advancement of Ru(edta) complexes (edta4- = ethylenediamineteraacetate) mediated reactions, including NO generation and its utilization, has not been systematically reviewed to date. This review aims to report the research progress that has been made in exploring the application of Ru(edta) complexes in trapping and generation of NO. Furthermore, utilization of the potential of Ru(edta) complexes to mimic NO synthase and nitrite reductase activity, including thermodynamics and kinetics of NO binding to Ru(edta) complexes, their NO scavenging (in vitro), and antitumor activity will be discussed. Also, the role of [Ru(edta)(NO)] in mediating electrochemical reduction of nitrite, S-nitrosylation of biological thiols, and cross-talk between NO and H2S, will be covered. Reports on the NO-related chemistry of Fe(edta) complexes showing similar behavior are contextualized in this review for comparison purposes. The research contributions compiled herein will provide in-depth mechanistic knowledge for understanding the diverse routes pertaining to the formation of the [Ru(edta)(NO)] species, and its role in effecting the aforementioned reactions of biochemical significance.
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Baranyai Z, Carniato F, Nucera A, Horváth D, Tei L, Platas-Iglesias C, Botta M. Defining the conditions for the development of the emerging class of Fe III-based MRI contrast agents. Chem Sci 2021; 12:11138-11145. [PMID: 34522311 PMCID: PMC8386674 DOI: 10.1039/d1sc02200h] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 07/07/2021] [Indexed: 02/05/2023] Open
Abstract
Fe(iii) complexes are attracting growing interest in chemists developing diagnostic probes for Magnetic Resonance Imaging because they leverage on an endogenous metal and show superior stability. However, in this case a detailed understanding of the relationship between the chemical structure of the complexes, their magnetic, thermodynamic, kinetic and redox properties and the molecular parameters governing the efficacy (relaxivity) is still far from being available. We have carried out an integrated 1H and 17O NMR relaxometric study as a function of temperature and magnetic field, on the aqua ion and three complexes chosen as reference models, together with theoretical calculations, to obtain accurate values of the parameters that control their relaxivity. Moreover, thermodynamic stability and dissociation kinetics of the Fe(iii) chelates, measured in association with the ascorbate reduction behaviour, highlight their role and mutual influence in achieving the stability required for use in vivo. An integrated 1H and 17O NMR relaxometric study on model systems allowed to highlight that the Fe(III) complexes might represent the best alternative to Gd-based MRI contrast agents at the magnetic fields of current and future clinical scanners.![]()
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Affiliation(s)
- Zsolt Baranyai
- Bracco Research Centre, Bracco Imaging S.p.A. Via Ribes 5 10010 Colleretto Giacosa Italy
| | - Fabio Carniato
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale "A. Avogadro" Viale T. Michel 11 15121 Alessandria Italy
| | - Alessandro Nucera
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale "A. Avogadro" Viale T. Michel 11 15121 Alessandria Italy
| | - Dávid Horváth
- Bracco Research Centre, Bracco Imaging S.p.A. Via Ribes 5 10010 Colleretto Giacosa Italy.,Department of Physical Chemistry, University of Debrecen Egyetem tér 1. H-4010 Debrecen Hungary
| | - Lorenzo Tei
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale "A. Avogadro" Viale T. Michel 11 15121 Alessandria Italy
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA), Departamento de Química, Facultade de Ciencias, Universidade da Coruña 15071 A Coruña Galicia Spain
| | - Mauro Botta
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale "A. Avogadro" Viale T. Michel 11 15121 Alessandria Italy
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Orzeł Ł, Oszajca M, Polaczek J, Porębska D, van Eldik R, Stochel G. High-Pressure Mechanistic Insight into Bioinorganic NO Chemistry. Molecules 2021; 26:molecules26164947. [PMID: 34443535 PMCID: PMC8401417 DOI: 10.3390/molecules26164947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/06/2021] [Accepted: 08/12/2021] [Indexed: 11/23/2022] Open
Abstract
Pressure is one of the most important parameters controlling the kinetics of chemical reactions. The ability to combine high-pressure techniques with time-resolved spectroscopy has provided a powerful tool in the study of reaction mechanisms. This review is focused on the supporting role of high-pressure kinetic and spectroscopic methods in the exploration of nitric oxide bioinorganic chemistry. Nitric oxide and other reactive nitrogen species (RNS) are important biological mediators involved in both physiological and pathological processes. Understanding molecular mechanisms of their interactions with redox-active metal/non-metal centers in biological targets, such as cofactors, prosthetic groups, and proteins, is crucial for the improved therapy of various diseases. The present review is an attempt to demonstrate how the application of high-pressure kinetic and spectroscopic methods can add additional information, thus enabling the mechanistic interpretation of various NO bioinorganic reactions.
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Affiliation(s)
- Łukasz Orzeł
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland; (Ł.O.); (M.O.); (J.P.); (D.P.)
| | - Maria Oszajca
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland; (Ł.O.); (M.O.); (J.P.); (D.P.)
| | - Justyna Polaczek
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland; (Ł.O.); (M.O.); (J.P.); (D.P.)
| | - Dominika Porębska
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland; (Ł.O.); (M.O.); (J.P.); (D.P.)
| | - Rudi van Eldik
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland; (Ł.O.); (M.O.); (J.P.); (D.P.)
- Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Egerlandstr 1, 91058 Erlangen, Germany
- Correspondence: (R.v.E.); (G.S.); Tel.: +48-66-777-2932 (R.v.E.); +48-12-686-2502 (G.S.)
| | - Grażyna Stochel
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland; (Ł.O.); (M.O.); (J.P.); (D.P.)
- Correspondence: (R.v.E.); (G.S.); Tel.: +48-66-777-2932 (R.v.E.); +48-12-686-2502 (G.S.)
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Anbu S, Hoffmann SHL, Carniato F, Kenning L, Price TW, Prior TJ, Botta M, Martins AF, Stasiuk GJ. A Single-Pot Template Reaction Towards a Manganese-Based T 1 Contrast Agent. Angew Chem Int Ed Engl 2021; 60:10736-10744. [PMID: 33624910 PMCID: PMC8252504 DOI: 10.1002/anie.202100885] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Indexed: 12/23/2022]
Abstract
Manganese-based contrast agents (MnCAs) have emerged as suitable alternatives to gadolinium-based contrast agents (GdCAs). However, due to their kinetic lability and laborious synthetic procedures, only a few MnCAs have found clinical MRI application. In this work, we have employed a highly innovative single-pot template synthetic strategy to develop a MnCA, MnLMe , and studied the most important physicochemical properties in vitro. MnLMe displays optimized r1 relaxivities at both medium (20 and 64 MHz) and high magnetic fields (300 and 400 MHz) and an enhanced r1b =21.1 mM-1 s-1 (20 MHz, 298 K, pH 7.4) upon binding to BSA (Ka =4.2×103 M-1 ). In vivo studies show that MnLMe is cleared intact into the bladder through renal excretion and has a prolonged blood half-life compared to the commercial GdCA Magnevist. MnLMe shows great promise as a novel MRI contrast agent.
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Affiliation(s)
- Sellamuthu Anbu
- Department of Biomedical SciencesUniversity of HullCottingham RoadHullHU6 7RXUK
- Department of ChemistryUniversity of HullCottingham RoadHullHU6 7RXUK
| | - Sabrina H. L. Hoffmann
- Werner Siemens Imaging CenterDepartment of Preclinical Imaging and RadiopharmacyEberhard Karls University Tübingen, Röntgenweg 13/172076TübingenGermany
| | - Fabio Carniato
- Dipartimento di Scienze e InnovazioneTecnologicaUniversità del Piemonte Orientale “A. Avogadro”Viale Teresa Michel 1115121AlessandriaItaly
| | - Lawrence Kenning
- MRI centreHull Royal Infirmary Hospital NHS TrustAnlaby RoadHullHU3 2JZUK
| | - Thomas W. Price
- Department of Imaging Chemistry and BiologySchool of Biomedical Engineering and Imaging SciencesKing's College LondonFourth Floor Lambeth WingSt Thomas' HospitalLondonSE1 7EHUK
| | - Timothy J. Prior
- Department of ChemistryUniversity of HullCottingham RoadHullHU6 7RXUK
| | - Mauro Botta
- Dipartimento di Scienze e InnovazioneTecnologicaUniversità del Piemonte Orientale “A. Avogadro”Viale Teresa Michel 1115121AlessandriaItaly
| | - Andre F. Martins
- Werner Siemens Imaging CenterDepartment of Preclinical Imaging and RadiopharmacyEberhard Karls University Tübingen, Röntgenweg 13/172076TübingenGermany
- Cluster of Excellence iFIT (EXC 2180) “Image-Guided and Functionally Instructed Tumor Therapies”University of TuebingenGermany
| | - Graeme J. Stasiuk
- Department of Imaging Chemistry and BiologySchool of Biomedical Engineering and Imaging SciencesKing's College LondonFourth Floor Lambeth WingSt Thomas' HospitalLondonSE1 7EHUK
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Anbu S, Hoffmann SHL, Carniato F, Kenning L, Price TW, Prior TJ, Botta M, Martins AF, Stasiuk GJ. A Single-Pot Template Reaction Towards a Manganese-Based T1 Contrast Agent. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 133:10831-10839. [PMID: 38505690 PMCID: PMC10947048 DOI: 10.1002/ange.202100885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Indexed: 12/20/2022]
Abstract
Manganese-based contrast agents (MnCAs) have emerged as suitable alternatives to gadolinium-based contrast agents (GdCAs). However, due to their kinetic lability and laborious synthetic procedures, only a few MnCAs have found clinical MRI application. In this work, we have employed a highly innovative single-pot template synthetic strategy to develop a MnCA, MnLMe, and studied the most important physicochemical properties in vitro. MnLMe displays optimized r 1 relaxivities at both medium (20 and 64 MHz) and high magnetic fields (300 and 400 MHz) and an enhanced r 1 b=21.1 mM-1 s-1 (20 MHz, 298 K, pH 7.4) upon binding to BSA (K a=4.2×103 M-1). In vivo studies show that MnLMe is cleared intact into the bladder through renal excretion and has a prolonged blood half-life compared to the commercial GdCA Magnevist. MnLMe shows great promise as a novel MRI contrast agent.
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Affiliation(s)
- Sellamuthu Anbu
- Department of Biomedical SciencesUniversity of HullCottingham RoadHullHU6 7RXUK
- Department of ChemistryUniversity of HullCottingham RoadHullHU6 7RXUK
| | - Sabrina H. L. Hoffmann
- Werner Siemens Imaging CenterDepartment of Preclinical Imaging and RadiopharmacyEberhard Karls University Tübingen, Röntgenweg 13/172076TübingenGermany
| | - Fabio Carniato
- Dipartimento di Scienze e InnovazioneTecnologicaUniversità del Piemonte Orientale “A. Avogadro”Viale Teresa Michel 1115121AlessandriaItaly
| | - Lawrence Kenning
- MRI centreHull Royal Infirmary Hospital NHS TrustAnlaby RoadHullHU3 2JZUK
| | - Thomas W. Price
- Department of Imaging Chemistry and BiologySchool of Biomedical Engineering and Imaging SciencesKing's College LondonFourth Floor Lambeth WingSt Thomas' HospitalLondonSE1 7EHUK
| | - Timothy J. Prior
- Department of ChemistryUniversity of HullCottingham RoadHullHU6 7RXUK
| | - Mauro Botta
- Dipartimento di Scienze e InnovazioneTecnologicaUniversità del Piemonte Orientale “A. Avogadro”Viale Teresa Michel 1115121AlessandriaItaly
| | - Andre F. Martins
- Werner Siemens Imaging CenterDepartment of Preclinical Imaging and RadiopharmacyEberhard Karls University Tübingen, Röntgenweg 13/172076TübingenGermany
- Cluster of Excellence iFIT (EXC 2180) “Image-Guided and Functionally Instructed Tumor Therapies”University of TuebingenGermany
| | - Graeme J. Stasiuk
- Department of Imaging Chemistry and BiologySchool of Biomedical Engineering and Imaging SciencesKing's College LondonFourth Floor Lambeth WingSt Thomas' HospitalLondonSE1 7EHUK
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11
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Porcar-Tost O, Pallier A, Esteban-Gómez D, Illa O, Platas-Iglesias C, Tóth É, Ortuño RM. Stability, relaxometric and computational studies on Mn 2+ complexes with ligands containing a cyclobutane scaffold. Dalton Trans 2021; 50:1076-1085. [PMID: 33367361 DOI: 10.1039/d0dt03402a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The stability constants of Mn2+ complexes with ligands containing a trans-1,2-cyclobutanediamine spacer functionalized with picolinate and/or carboxylate functions were determined using potentiometric titrations (25 °C, 0.1 M KCl). The stability constant of the complex with a hexadentate ligand containing four acetate groups (L14-, log KMnL = 10.26) is improved upon replacing one (L24-, log KMnL = 14.71) or two (L34-, log KMnL = 15.81) carboxylate groups with picolinates. The [Mn(L1)]2- complex contains a water molecule coordinated to the metal ion in aqueous solutions, as evidenced by 1H NMRD studies and 17O chemical shifts and transverse relaxation rates. The 1H relaxivities determined at 60 MHz (3.3 and 2.4 mM-1 s-1 at 25 and 37 °C, respectively) are comparable to those of monohydrated complexes such as [Mn(edta)]2-. The exchange rate of the inner-sphere water molecule (k = 248 × 106 s-1) is slightly lower than that of the edta4- analogue. DFT calculations (M11/def2-TZVP) suggest that the water exchange reaction follows a dissociatively activated mechanism, providing activation parameters in reasonably good agreement with the experimental data. DFT calculations also show that the 17O hyperfine coupling constant A/ℏ is affected slightly by changes in the Mn-Owater distance and the orientation of the water molecule with respect to the Mn-O vector.
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Affiliation(s)
- Oriol Porcar-Tost
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain.
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Garda Z, Molnár E, Hamon N, Barriada JL, Esteban-Gómez D, Váradi B, Nagy V, Pota K, Kálmán FK, Tóth I, Lihi N, Platas-Iglesias C, Tóth É, Tripier R, Tircsó G. Complexation of Mn(II) by Rigid Pyclen Diacetates: Equilibrium, Kinetic, Relaxometric, Density Functional Theory, and Superoxide Dismutase Activity Studies. Inorg Chem 2020; 60:1133-1148. [PMID: 33378171 DOI: 10.1021/acs.inorgchem.0c03276] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We report the Mn(II) complexes with two pyclen-based ligands (pyclen = 3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene) functionalized with acetate pendant arms at either positions 3,6 (3,6-PC2A) or 3,9 (3,9-PC2A) of the macrocyclic fragment. The 3,6-PC2A ligand was synthesized in five steps from pyclen oxalate by protecting one of the secondary amine groups of pyclen using Alloc protecting chemistry. The complex with 3,9-PC2A is characterized by a higher thermodynamic stability [log KMnL = 17.09(2)] than the 3,6-PC2A analogue [log KMnL = 15.53(1); 0.15 M NaCl]. Both complexes contain a water molecule coordinated to the metal ion, which results in relatively high 1H relaxivities (r1p = 2.72 and 2.91 mM-1 s-1 for the complexes with 3,6-PC2A and 3,9-PC2A, respectively, at 25 °C and 0.49 T). The coordinated water molecule displays fast exchange kinetics with the bulk in both cases; the rates (kex298) are 140 × 106 and 126 × 106 s-1 for [Mn(3,6-PC2A)(H2O)] and [Mn(3,9-PC2A)(H2O)], respectively. The two complexes were found to be remarkably inert with respect to their dissociation, with half-lives of 63 and 21 h, respectively, at pH = 7.4 in the presence of excess Cu(II). The r1p values recorded in blood serum remain constant at least over a period of 120 h. Cyclic voltammetry experiments show irreversible oxidation features shifted to higher potentials with respect to [Mn(EDTA)(H2O)]2- (H4EDTA = ethylenediaminetetraacetic acid) and [Mn(PhDTA)(H2O)]2- (H4PhDTA = phenylenediamine-N,N,N',N'-tetraacetic acid), indicating that the PC2A complexes reported here have a lower tendency to stabilize Mn(III). The superoxide dismutase activity of the Mn(II) complexes was tested using the xanthine/xanthine oxidase/p-nitro blue tetrazolium chloride assay at pH = 7.8. The Mn(II) complexes of 3,6-PC2A and 3,9-PC2A are capable of assisting decomposition of the superoxide anion radical. The kinetic rate constant of the complex of 3,9-PC2A is smaller by 1 order of magnitude than that of 3,6-PC2A.
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Affiliation(s)
| | | | - Nadège Hamon
- Université Brest, UMR-CNRS 6521, CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
| | - José Luis Barriada
- Centro de Investigacións Científicas Avanzadas and Departamento de Química, Universidade da Coruña, Campus da Zapateira, Rúa da Fraga 10, 15008 A Coruña, Spain
| | - David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas and Departamento de Química, Universidade da Coruña, Campus da Zapateira, Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Balázs Váradi
- Doctoral School of Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | | | | | | | | | | | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas and Departamento de Química, Universidade da Coruña, Campus da Zapateira, Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Éva Tóth
- Centre de Biophysique Moléculaire, CNRS, rue Charles Sadron, 45071 Orléans, Cedex 2, France
| | - Raphaël Tripier
- Université Brest, UMR-CNRS 6521, CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
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Gupta A, Caravan P, Price WS, Platas-Iglesias C, Gale EM. Applications for Transition-Metal Chemistry in Contrast-Enhanced Magnetic Resonance Imaging. Inorg Chem 2020; 59:6648-6678. [PMID: 32367714 DOI: 10.1021/acs.inorgchem.0c00510] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Contrast-enhanced magnetic resonance imaging (MRI) is an indispensable tool for diagnostic medicine. However, safety concerns related to gadolinium in commercial MRI contrast agents have emerged in recent years. For patients suffering from severe renal impairment, there is an important unmet medical need to perform contrast-enhanced MRI without gadolinium. There are also concerns over the long-term effects of retained gadolinium within the general patient population. Demand for gadolinium-free MRI contrast agents is driving a new wave of inorganic chemistry innovation as researchers explore paramagnetic transition-metal complexes as potential alternatives. Furthermore, advances in personalized care making use of molecular-level information have motivated inorganic chemists to develop MRI contrast agents that can detect pathologic changes at the molecular level. Recent studies have highlighted how reaction-based modulation of transition-metal paramagnetism offers a highly effective mechanism to achieve MRI contrast enhancement that is specific to biochemical processes. This Viewpoint highlights how recent advances in transition-metal chemistry are leading the way for a new generation of MRI contrast agents.
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Affiliation(s)
- Abhishek Gupta
- Nanoscale Organisation and Dynamics Group, School of Science and Health, Western Sydney University, Penrith, New South Wales 2751, Australia.,Ingham Institute of Applied Medical Research, Liverpool, New South Wales 2170, Australia
| | | | - William S Price
- Nanoscale Organisation and Dynamics Group, School of Science and Health, Western Sydney University, Penrith, New South Wales 2751, Australia.,Ingham Institute of Applied Medical Research, Liverpool, New South Wales 2170, Australia
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, A Coruña, Galicia 15071, Spain
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14
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Hubbard CD, Chatterjee D, Oszajca M, Polaczek J, Impert O, Chrzanowska M, Katafias A, Puchta R, van Eldik R. Inorganic reaction mechanisms. A personal journey. Dalton Trans 2020; 49:4599-4659. [PMID: 32162632 DOI: 10.1039/c9dt04620h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
This review covers highlights of the work performed in the van Eldik group on inorganic reaction mechanisms over the past two decades in the form of a personal journey. Topics that are covered include, from NO to HNO chemistry, peroxide activation in model porphyrin and enzymatic systems, the wonder-world of RuIII(edta) chemistry, redox chemistry of Ru(iii) complexes, Ru(ii) polypyridyl complexes and their application, relevant physicochemical properties and reaction mechanisms in ionic liquids, and mechanistic insight from computational chemistry. In each of these sections, typical examples of mechanistic studies are presented in reference to related work reported in the literature.
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Affiliation(s)
- Colin D Hubbard
- Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Egerlandstr. 1, 91058 Erlangen, Germany.
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15
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Peters JA, Djanashvili K, Geraldes CF, Platas-Iglesias C. The chemical consequences of the gradual decrease of the ionic radius along the Ln-series. Coord Chem Rev 2020. [DOI: 10.1016/j.ccr.2019.213146] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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16
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Bond CJ, Sokolow GE, Crawley MR, Burns PJ, Cox JM, Mayilmurugan R, Morrow JR. Exploring Inner-Sphere Water Interactions of Fe(II) and Co(II) Complexes of 12-Membered Macrocycles To Develop CEST MRI Probes. Inorg Chem 2019; 58:8710-8719. [PMID: 31247845 DOI: 10.1021/acs.inorgchem.9b01072] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Several paramagnetic Co(II) and Fe(II) macrocyclic complexes were prepared with the goal of introducing a bound water ligand to produce paramagnetically shifted water 1H resonances and for paramagnetic chemical exchange saturation transfer (paraCEST) applications. Three 12-membered macrocycles with amide pendent groups including 1,7-bis(carbamoylmethyl)-1,4,7,10-tetraazacyclodocane (DCMC), 4,7,10-tris(carbamoylmethyl)-,4,7,10-triaza-12-crown-ether (N3OA), and 4,10-bis(carbamoylmethyl)-4,10-diaza-12-crown-ether (NODA) were prepared and their Co(II) complexes were characterized in the solid state and in solution. The crystal structure of [Co(DCMC)]Br2 featured a six-coordinated Co(II) center with distorted octahedral geometry, while [Co(NODA)(OH2)]Cl2 and [Co(N3OA)](NO3)2 were seven-coordinated. The analogous Fe(II) complexes of NODA and NO3A were successfully prepared, but the complex of DCMC oxidized rapidly to the Fe(III) form. Similarly, [Fe(NODA)]2+ oxidized over several days, forming crystals of the Fe(III) complex isolated as the μ-O bridged dimer. Magnetic susceptibility values and paramagnetic NMR spectra of the Fe(II) complexes of NODA and N3OA, as well as Co(II) complexes of DCMC, NODA, and N3OA, were consistent with high spin complexes. CEST peaks ranging from 60 ppm to 70 ppm, attributed to NH groups of the amide pendents, were identified. Variable-temperature 17O NMR spectra of Co(II) and Fe(II) NODA complexes were consistent with rapid exchange of the water ligand with bulk water. Notably, the Co(II) and Fe(II) complexes presented here produced substantial paramagnetic shifts of bulk water 1H resonances, independent of having an inner-sphere water.
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Affiliation(s)
- Christopher J Bond
- Department of Chemistry , University at Buffalo, State University of New York , Amherst , New York 14260 , United States
| | - Gregory E Sokolow
- Department of Chemistry , University at Buffalo, State University of New York , Amherst , New York 14260 , United States
| | - Matthew R Crawley
- Department of Chemistry , University at Buffalo, State University of New York , Amherst , New York 14260 , United States
| | - Patrick J Burns
- Department of Chemistry , University at Buffalo, State University of New York , Amherst , New York 14260 , United States
| | - Jordan M Cox
- Department of Chemistry , University at Buffalo, State University of New York , Amherst , New York 14260 , United States
| | - Ramasamy Mayilmurugan
- Department of Chemistry , University at Buffalo, State University of New York , Amherst , New York 14260 , United States
| | - Janet R Morrow
- Department of Chemistry , University at Buffalo, State University of New York , Amherst , New York 14260 , United States
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17
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Wang H, Jordan VC, Ramsay IA, Sojoodi M, Fuchs BC, Tanabe KK, Caravan P, Gale EM. Molecular Magnetic Resonance Imaging Using a Redox-Active Iron Complex. J Am Chem Soc 2019; 141:5916-5925. [PMID: 30874437 PMCID: PMC6726119 DOI: 10.1021/jacs.9b00603] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We introduce a redox-active iron complex, Fe-PyC3A, as a biochemically responsive MRI contrast agent. Switching between Fe3+-PyC3A and Fe2+-PyC3A yields a full order of magnitude relaxivity change that is field-independent between 1.4 and 11.7 T. The oxidation of Fe2+-PyC3A to Fe3+-PyC3A by hydrogen peroxide is very rapid, and we capitalized on this behavior for the molecular imaging of acute inflammation, which is characterized by elevated levels of reactive oxygen species. Injection of Fe2+-PyC3A generates strong, selective contrast enhancement of inflamed pancreatic tissue in a mouse model (caerulein/LPS model). No significant signal enhancement is observed in normal pancreatic tissue (saline-treated mice). Importantly, signal enhancement of the inflamed pancreas correlates strongly and significantly with ex vivo quantitation of the pro-inflammatory biomarker myeloperoxidase. This is the first example of using metal ion redox for the MR imaging of pathologic change in vivo. Redox-active Fe3+/2+ complexes represent a new design paradigm for biochemically responsive MRI contrast agents.
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Affiliation(s)
- Huan Wang
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Veronica Clavijo Jordan
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
- Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114, United States
| | - Ian A. Ramsay
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
| | - Mozhdeh Sojoodi
- Division of Surgical Oncology, Massachusetts General Hospital/Harvard Medical School, WRN401, 55 Fruit Street, Boston, Massachusetts 02114, United States
| | - Bryan C. Fuchs
- Division of Surgical Oncology, Massachusetts General Hospital/Harvard Medical School, WRN401, 55 Fruit Street, Boston, Massachusetts 02114, United States
| | - Kenneth K. Tanabe
- Division of Surgical Oncology, Massachusetts General Hospital/Harvard Medical School, WRN401, 55 Fruit Street, Boston, Massachusetts 02114, United States
| | - Peter Caravan
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
- Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, Boston, Massachusetts 02114, United States
| | - Eric M. Gale
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, 149 Thirteenth Street, Charlestown, Massachusetts 02129, United States
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18
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Molnár E, Váradi B, Garda Z, Botár R, Kálmán FK, Tóth É, Platas-Iglesias C, Tóth I, Brücher E, Tircsó G. Remarkable differences and similarities between the isomeric Mn(II)- cis - and trans- 1,2-diaminocyclohexane- N , N , N ′, N ′-tetraacetate complexes. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2017.07.071] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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19
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Laine S, Bonnet CS, Kálmán FK, Garda Z, Pallier A, Caillé F, Suzenet F, Tircsó G, Tóth É. Mn2+ complexes of open-chain ligands with a pyridine backbone: less donor atoms lead to higher kinetic inertness. NEW J CHEM 2018. [DOI: 10.1039/c8nj00648b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The loss of a coordinating donor atom in the ligand leads to lower thermodynamic stability, but higher kinetic inertness of Mn2+ complexes.
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Affiliation(s)
- Sophie Laine
- Centre de Biophysique Moléculaire
- CNRS
- Université d’Orléans
- rue Charles Sadron
- 45071 Orléans
| | - Célia S. Bonnet
- Centre de Biophysique Moléculaire
- CNRS
- Université d’Orléans
- rue Charles Sadron
- 45071 Orléans
| | - Ferenc K. Kálmán
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- Debrecen
- Hungary
| | - Zoltán Garda
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- Debrecen
- Hungary
| | - Agnès Pallier
- Centre de Biophysique Moléculaire
- CNRS
- Université d’Orléans
- rue Charles Sadron
- 45071 Orléans
| | - Fabien Caillé
- Centre de Biophysique Moléculaire
- CNRS
- Université d’Orléans
- rue Charles Sadron
- 45071 Orléans
| | - Franck Suzenet
- Institut de Chimie Organique et Analytique
- UMR 7311 CNRS
- Université d’Orléans
- rue de Chartres
- 45067 Orléans
| | - Gyula Tircsó
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- Debrecen
- Hungary
| | - Éva Tóth
- Centre de Biophysique Moléculaire
- CNRS
- Université d’Orléans
- rue Charles Sadron
- 45071 Orléans
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20
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Pota K, Garda Z, Kálmán FK, Barriada JL, Esteban-Gómez D, Platas-Iglesias C, Tóth I, Brücher E, Tircsó G. Taking the next step toward inert Mn2+ complexes of open-chain ligands: the case of the rigid PhDTA ligand. NEW J CHEM 2018. [DOI: 10.1039/c8nj00121a] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Equilibrium, dissociation kinetics, relaxometric and electrochemical properties of the [Mn(PhDTA)]2− complex were investigated and the structure of the [Mn(PhDTA)]2− complex was studied by using DFT calculations.
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Affiliation(s)
- Kristof Pota
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- H-4032 Debrecen
- Hungary
| | - Zoltán Garda
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- H-4032 Debrecen
- Hungary
| | - Ferenc Krisztián Kálmán
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- H-4032 Debrecen
- Hungary
| | - José Luis Barriada
- Centro de Investigaciones Científicas Avanzadas (CICA)
- Departamento de Química, Universidade da Coruña
- Spain
| | - David Esteban-Gómez
- Centro de Investigaciones Científicas Avanzadas (CICA)
- Departamento de Química, Universidade da Coruña
- Spain
| | - Carlos Platas-Iglesias
- Centro de Investigaciones Científicas Avanzadas (CICA)
- Departamento de Química, Universidade da Coruña
- Spain
| | - Imre Tóth
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- H-4032 Debrecen
- Hungary
| | - Ernő Brücher
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- H-4032 Debrecen
- Hungary
| | - Gyula Tircsó
- Department of Inorganic and Analytical Chemistry
- Faculty of Science and Technology
- University of Debrecen
- H-4032 Debrecen
- Hungary
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21
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Complex of ytterbium ethylenediaminetetraacetate as combined NMR paramagnetic probe for in situ control of temperature and pH in aqueous media. Polyhedron 2018. [DOI: 10.1016/j.poly.2017.11.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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22
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Vanasschen C, Molnár E, Tircsó G, Kálmán FK, Tóth É, Brandt M, Coenen HH, Neumaier B. Novel CDTA-based, Bifunctional Chelators for Stable and Inert MnII Complexation: Synthesis and Physicochemical Characterization. Inorg Chem 2017. [DOI: 10.1021/acs.inorgchem.7b00460] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christian Vanasschen
- Institut für Neurowissenschaften und Medizin, INM-5: Nuklearchemie, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Enikő Molnár
- Department of Inorganic and Analytical Chemistry, Faculty
of Science and Technology, University of Debrecen, Debrecen, Egyetem tér 1, H-4010, Hungary
| | - Gyula Tircsó
- Department of Inorganic and Analytical Chemistry, Faculty
of Science and Technology, University of Debrecen, Debrecen, Egyetem tér 1, H-4010, Hungary
| | - Ferenc K. Kálmán
- Department of Inorganic and Analytical Chemistry, Faculty
of Science and Technology, University of Debrecen, Debrecen, Egyetem tér 1, H-4010, Hungary
- Centre de Biophysique Moléculaire,
CNRS, Université d’Orléans, rue Charles Sadron, 45071 Orléans, Cedex 2, France
- Le Studium, Loire Valley Institute for Advanced Studies, 1 Rue
Dupanloup, 45000 Orléans, France
| | - Éva Tóth
- Centre de Biophysique Moléculaire,
CNRS, Université d’Orléans, rue Charles Sadron, 45071 Orléans, Cedex 2, France
| | - Marie Brandt
- Institut für Neurowissenschaften und Medizin, INM-5: Nuklearchemie, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Heinz H. Coenen
- Institut für Neurowissenschaften und Medizin, INM-5: Nuklearchemie, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Bernd Neumaier
- Institut für Neurowissenschaften und Medizin, INM-5: Nuklearchemie, Forschungszentrum Jülich GmbH, Jülich, Germany
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23
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Vanasschen C, Brandt M, Ermert J, Coenen HH. Radiolabelling with isotopic mixtures of (52g/55)Mn(II) as a straight route to stable manganese complexes for bimodal PET/MR imaging. Dalton Trans 2016; 45:1315-21. [PMID: 26685974 DOI: 10.1039/c5dt04270d] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Radiolabelling using isotopic mixtures of (52g/55)Mn(ii) offers fast and easy access to new small molecule PET/MR tracers, composed of chemically identical reporting units. trans-1,2-Diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA) was radiolabelled with carrier-added (52g)Mn(ii) in >99% radiochemical yield, producing the first manganese-based bimodal PET/MR probe. The Mn-CDTA chelate was shown to be very stable to air oxidation and sufficiently inert to decomplexation in blood serum. These data sparked our interest in functionalized CDTA ligands for the design of optimized PET/MR tracers.
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Affiliation(s)
- Christian Vanasschen
- Institut für Neurowissenschaften und Medizin, INM-5: Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany.
| | - Marie Brandt
- Institut für Neurowissenschaften und Medizin, INM-5: Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany.
| | - Johannes Ermert
- Institut für Neurowissenschaften und Medizin, INM-5: Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany.
| | - Heinz H Coenen
- Institut für Neurowissenschaften und Medizin, INM-5: Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany.
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Mundlapati VR, Jena P, Acharya AN, Kar AK, Dash AC, Biswal HS. Water exchange reaction of a manganese catalase mimic: oxygen-17 NMR relaxometry study on (aqua)manganese(iii) in a salen scaffold and its reactions in a mildly basic medium. RSC Adv 2016. [DOI: 10.1039/c6ra23154c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Water exchange of trans-[MnIII(salen)(OH2)2]+ studied by line broadening 17OH2 NMR discloses its mechanism as associative interchange (Ia).
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Affiliation(s)
- V. Rao Mundlapati
- School of Chemical Sciences
- National Institute of Science Education and Research (NISER)
- Institute of Physics Campus
- Bhubaneswar 751 005
- India
| | - Priyambada Jena
- Department of Chemistry
- College of Engineering and Technology
- Bhubaneswar 751003
- India
| | - Achyut N. Acharya
- Department of Chemistry
- College of Engineering and Technology
- Bhubaneswar 751003
- India
| | - Akshaya K. Kar
- Department of Chemistry
- Utkal University
- Bhubaneswar 751004
- India
| | - Anadi C. Dash
- Department of Chemistry
- Utkal University
- Bhubaneswar 751004
- India
| | - Himansu S. Biswal
- School of Chemical Sciences
- National Institute of Science Education and Research (NISER)
- Institute of Physics Campus
- Bhubaneswar 751 005
- India
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25
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Formation of anti- versus syn-dinuclear CuII complexes from bis-glycinamide ligands. Synergistic roles of a His/His dyad and supporting-ligand backbones in CuII binding. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2015.11.063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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26
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Gale EM, Atanasova IP, Blasi F, Ay I, Caravan P. A Manganese Alternative to Gadolinium for MRI Contrast. J Am Chem Soc 2015; 137:15548-57. [PMID: 26588204 PMCID: PMC4764508 DOI: 10.1021/jacs.5b10748] [Citation(s) in RCA: 222] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used to diagnose soft tissue and vascular abnormalities. However, safety concerns limit the use of iodinated and gadolinium (Gd)-based CT and MRI contrast media in renally compromised patients. With an estimated 14% of the US population suffering from chronic kidney disease (CKD), contrast media compatible with renal impairment is sorely needed. We present the new manganese(II) complex [Mn(PyC3A)(H2O)](-) as a Gd alternative. [Mn(PyC3A)(H2O)](-) is among the most stable Mn(II) complexes at pH 7.4 (log KML = 11.40). In the presence of 25 mol equiv of Zn at pH 6.0, 37 °C, [Mn(PyC3A)(H2O)](-) is 20-fold more resistant to dissociation than [Gd(DTPA)(H2O)](2-). Relaxivity of [Mn(PyC3A)(H2O)](-) in blood plasma is comparable to commercial Gd contrast agents. Biodistribution analysis confirms that [Mn(PyC3A)(H2O)](-) clears via a mixed renal/hepatobiliary pathway with >99% elimination by 24 h. [Mn(PyC3A)(H2O)](-) was modified to form a bifunctional chelator and 4 chelates were conjugated to a fibrin-specific peptide to give Mn-FBP. Mn-FBP binds the soluble fibrin fragment DD(E) with Kd = 110 nM. Per Mn relaxivity of Mn-FBP is 4-fold greater than [Mn(PyC3A)(H2O)](-) and increases 60% in the presence of fibrin, consistent with binding. Mn-FBP provided equivalent thrombus enhancement to the state of the art Gd analogue, EP-2104R, in a rat model of arterial thrombosis. Mn metabolite analysis reveals no evidence of dechelation and the probe was >99% eliminated after 24 h. [Mn(PyC3A)(H2O)](-) is a lead development candidate for an imaging probe that is compatible with renally compromised patients.
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Affiliation(s)
- Eric M. Gale
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Iliyana P. Atanasova
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Francesco Blasi
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Ilknur Ay
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
| | - Peter Caravan
- The Athinoula A. Martinos Center for Biomedical Imaging, The Institute for Innovation in Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129
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Mereshchenko AS, Olshin PK, Karabaeva KE, Panov MS, Wilson RM, Kochemirovsky VA, Skripkin MY, Tveryanovich YS, Tarnovsky AN. Mechanism of Formation of Copper(II) Chloro Complexes Revealed by Transient Absorption Spectroscopy and DFT/TDDFT Calculations. J Phys Chem B 2015; 119:8754-63. [PMID: 26079181 DOI: 10.1021/acs.jpcb.5b03889] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Copper(II) complexes are extremely labile with typical ligand exchange rate constants on the order of 10(6)-10(9) M(-1) s(-1). As a result, it is often difficult to identify the actual formation mechanism of these complexes. In this work, using UV-vis transient absorption when probing in a broad time range (20 ps to 8 μs) in conjunction with DFT/TDDFT calculations, we studied the dynamics and underlying reaction mechanisms of the formation of extremely labile copper(II) CuCl4(2-) chloro complexes from copper(II) CuCl3(-) trichloro complexes and chloride ions. These two species, produced via photochemical dissociation of CuCl4(2-) upon 420 nm excitation into the ligand-to-metal-charge-transfer electronic state, are found to recombine into parent complexes with bimolecular rate constants of (9.0 ± 0.1) × 10(7) and (5.3 ± 0.4) × 10(8) M(-1) s(-1) in acetonitrile and dichloromethane, respectively. In dichloromethane, recombination occurs via a simple one-step addition. In acetonitrile, where [CuCl3](-) reacts with the solvent to form a [CuCl3CH3CN](-) complex in less than 20 ps, recombination takes place via ligand exchange described by the associative interchange mechanism that involves a [CuCl4CH3CN](2-) intermediate. In both solvents, the recombination reaction is potential energy controlled.
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Affiliation(s)
- Andrey S Mereshchenko
- †Institute of Chemistry, Saint-Petersburg State University, 198504 Saint-Petersburg, Russian Federation
| | - Pavel K Olshin
- †Institute of Chemistry, Saint-Petersburg State University, 198504 Saint-Petersburg, Russian Federation
| | - Kanykey E Karabaeva
- ‡Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, United States
| | - Maxim S Panov
- †Institute of Chemistry, Saint-Petersburg State University, 198504 Saint-Petersburg, Russian Federation
| | - R Marshall Wilson
- ‡Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, United States
| | - Vladimir A Kochemirovsky
- †Institute of Chemistry, Saint-Petersburg State University, 198504 Saint-Petersburg, Russian Federation
| | - Mikhail Yu Skripkin
- †Institute of Chemistry, Saint-Petersburg State University, 198504 Saint-Petersburg, Russian Federation
| | - Yury S Tveryanovich
- †Institute of Chemistry, Saint-Petersburg State University, 198504 Saint-Petersburg, Russian Federation
| | - Alexander N Tarnovsky
- ‡Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, United States
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28
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Elhabiri M, Abada S, Sy M, Nonat A, Choquet P, Esteban-Gómez D, Cassino C, Platas-Iglesias C, Botta M, Charbonnière LJ. Importance of Outer-Sphere and Aggregation Phenomena in the Relaxation Properties of Phosphonated Gadolinium Complexes with Potential Applications as MRI Contrast Agents. Chemistry 2015; 21:6535-46. [DOI: 10.1002/chem.201500155] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Indexed: 11/10/2022]
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29
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Janicki R, Mondry A. Thermodynamics of the hydration equilibrium derived from the luminescence spectra of the solid state for the case of the Eu–EDTA system. Phys Chem Chem Phys 2015; 17:29558-65. [DOI: 10.1039/c5cp02429c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Spectroscopic evidence of the hydration equilibrium for the case of the Eu–EDTA system.
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Affiliation(s)
- R. Janicki
- University of Wrocław
- Faculty of Chemistry
- F. Joliot-Curie 14
- 50-383 Wrocław
- Poland
| | - A. Mondry
- University of Wrocław
- Faculty of Chemistry
- F. Joliot-Curie 14
- 50-383 Wrocław
- Poland
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30
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Negri R, Baranyai Z, Tei L, Giovenzana GB, Platas-Iglesias C, Bényei AC, Bodnár J, Vágner A, Botta M. Lower denticity leading to higher stability: structural and solution studies of Ln(III)-OBETA complexes. Inorg Chem 2014; 53:12499-511. [PMID: 25387307 DOI: 10.1021/ic5020225] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The heptadentate ligand OBETA (2,2'-oxybis(ethylamine)-N,N,N',N'-tetraacetic acid) was reported to form complexes with Ln(3+) ions more stable than those formed by the octadentate and more popular congener EGTA (ethylene glycol O,O'-bis(ethylamine)-N,N,N',N'-tetraacetic acid). The structural features leading to this puzzling coordination paradox were investigated by X-ray diffraction, solution state NMR, molecular modeling, and relaxometric studies. The stability constant of Gd(OBETA) (log KGdL = 19.37, 0.1 M KCl) is 2 orders of magnitude higher than that of the higher denticity analogue Gd(EGTA) (log KGdL = 17.66, 0.1 M KCl). The half-lives (t1/2) for the dissociation reactions of Gd(OBETA) and Gd(EGTA) ([Cu(2+)]tot = 0.2 mM, [Cit(3-)]tot = 0.5 mM, [PO4(3-)]tot = 1.0 mM, and [CO3(2-)]tot = 25 mM at pH = 7.4 and 25 °C in 0.1 M KCl solution) are 6.8 and 0.63 h, respectively, reflecting the much higher inertness of Gd(OBETA) near physiological conditions. NMR studies and DFT calculations using the B3LYP functional and a large-core ECP indicate that the [Gd(OBETA)(H2O)2](-) complex most likely exists in solution as the Δ(λλ)(δδδδ)A/Λ(δδ)(λλλλ)A enantiomeric pair, with an activation free energy for the enantiomerization process of ∼40 kJ·mol(-1). The metal ion is nine-coordinate by seven donor atoms of the ligand and two inner-sphere water molecules. The X-ray crystal structure of [C(NH2)3]3[Lu(OBETA)(CO3)]·2H2O is in agreement with the predictions of DFT calculations, the two coordinated water molecules being replaced by a bidentate carbonate anion. The (1)H NMRD and (17)O NMR study revealed that the two inner-sphere water molecules in Gd(OBETA) are endowed with a relatively fast water exchange rate (kex(298) = 13 × 10(6) s(-1)). The higher thermodynamic stability and inertness of Ln(OBETA) complexes, peaking in the center of the 4f series, combined with the presence of two coordinated water molecules suggests that Gd(OBETA) is a promising paramagnetic probe for MRI applications.
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Affiliation(s)
- Roberto Negri
- Dipartimento di Scienze del Farmaco, Università degli Studi del Piemonte Orientale "A. Avogadro" , Largo Donegani 2/3, I-28100 Novara, Italy
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31
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Janicki R, Mondry A. A new approach to determination of hydration equilibria constants for the case of [Er(EDTA)(H2O)n]−complexes. Phys Chem Chem Phys 2014; 16:26823-31. [DOI: 10.1039/c4cp04093g] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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32
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Gale EM, Mukherjee S, Liu C, Loving GS, Caravan P. Structure-redox-relaxivity relationships for redox responsive manganese-based magnetic resonance imaging probes. Inorg Chem 2014; 53:10748-61. [PMID: 25226090 PMCID: PMC4186673 DOI: 10.1021/ic502005u] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Indexed: 12/11/2022]
Abstract
A library of 10 Mn-containing complexes capable of switching reversibly between the Mn(II) and Mn(III) oxidation states was prepared and evaluated for potential usage as MRI reporters of tissue redox activity. We synthesized N-(2-hydroxybenzyl)-N,N',N'-ethylenediaminetriacetic acid (HBET) and N-(2-hydroxybenzyl-N,N',N'-trans-1,2-cyclohexylenediaminetriacetic acid (CyHBET) ligands functionalized (-H, -OMe, -NO2) at the 5-position of the aromatic ring. The Mn(II) complexes of all ligands and the Mn(III) complexes of the 5-H and 5-NO2 functionalized ligands were synthesized and isolated, but the Mn(III) complexes with the 5-OMe functionalized ligands were unstable. (1)H relaxivity of the 10 isolable complexes was measured at pH 7.4 and 37 °C, 1.4 T. Thermodynamic stability, pH-dependent complex speciation, hydration state, water exchange kinetics of the Mn(II) complexes, and pseudo-first order reduction kinetics of the Mn(III) complexes were studied using a combination of pH-potentiometry, UV-vis spectroscopy, and (1)H and (17)O NMR measurements. The effects of ligand structural and electronic modifications on the Mn(II/III) redox couple were studied by cyclic voltammetry. The Mn(II) complexes are potent relaxation agents as compared to the corresponding Mn(III) species with [Mn(II)(CyHBET)(H2O)](2-) exhibiting a 7.5-fold higher relaxivity (3.3 mM(-1) s(-1)) than the oxidized form (0.4 mM(-1) s(-1)). At pH 7.4, Mn(II) exists as a mixture of fully deprotonated (ML) and monoprotonated (HML) complexes and Mn(II) complex stability decreases as the ligands become more electron-releasing (pMn for 10 μM [Mn(II)(CyHBET-R')(H2O)](2-) decreases from 7.6 to 6.2 as R' goes from -NO2 to -OMe, respectively). HML speciation increases as the electron-releasing nature of the phenolato-O donor increases. The presence of a water coligand is maintained upon conversion from HML to ML, but the water exchange rate of ML is faster by up to 2 orders of magnitude (k(ex)(310) for H[Mn(II)(CyHBET)(H2O)](-) and [Mn(II)(CyHBET)(H2O)](2-) are 1.2 × 10(8) and 1.0 × 10(10) s(-1), respectively). The Mn(II/III) redox potential can be tuned over a range of 0.30 V (E(1/2) = 0.27-0.57 V) through electronic modifications to the 5-substituent of the aromatic ligand component. However, care must be taken in tuning the ligand electronics to avoid Mn(III)-ligand autoredox. Taken together, these results serve to establish criteria for optimizing Mn(III) versus Mn(II) relaxivity differentials, complex stability, and Mn(II/III) redox potential.
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Affiliation(s)
| | | | - Cynthia Liu
- The Athinoula
A. Martinos Center for Biomedical Imaging, Department of Radiology,
Massachusetts General Hospital, Harvard
Medical School, 149 Thirteenth
Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - Galen S. Loving
- The Athinoula
A. Martinos Center for Biomedical Imaging, Department of Radiology,
Massachusetts General Hospital, Harvard
Medical School, 149 Thirteenth
Street, Suite 2301, Charlestown, Massachusetts 02129, United States
| | - Peter Caravan
- The Athinoula
A. Martinos Center for Biomedical Imaging, Department of Radiology,
Massachusetts General Hospital, Harvard
Medical School, 149 Thirteenth
Street, Suite 2301, Charlestown, Massachusetts 02129, United States
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33
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Babailov SP, Dubovskii PV, Zapolotsky EN. Paramagnetic lanthanides as magnetic resonance thermo-sensors and probes of molecular dynamics: Holmium-DOTA complex. Polyhedron 2014. [DOI: 10.1016/j.poly.2014.04.067] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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34
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Meier R, Platas-Iglesias C, Heinemann FW, Linti G, Schulte J, Srivastava SK. Secrets of Solid State and Aqueous Solution Structures of [Ni(tmdta)]2–. Inorg Chem 2014; 53:6684-97. [DOI: 10.1021/ic5004325] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Roland Meier
- Inorganic
Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058 Erlangen, Germany
| | - Carlos Platas-Iglesias
- Departamento
de Química Fundamental, Universidade da Coruña, Campus
da Zapateira, Rúa da Fraga 10, 15008, Coruña, Spain
| | - Frank W. Heinemann
- Inorganic
Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 1, 91058 Erlangen, Germany
| | - Gerald Linti
- Anorganisch-Chemisches
Institut, University of Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany
| | - Jürgen Schulte
- Chemistry
Department, Binghamton University, State University of New York, P.O. Box 6000 Binghamton, New York 13902-6000, United States
| | - Sunil K. Srivastava
- Department
of Pure and Applied Physics, Guru Ghasidas Vishwavidyalaya, Koni, Bilaspur Chhattisgarh 495009, India
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35
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Quantum chemical investigations of the water exchange mechanism on [Al(III)(H₂O)₅(L)]²⁺ as a function of the donor strength of the anionic L. J Mol Model 2014; 20:2083. [PMID: 24531724 DOI: 10.1007/s00894-014-2083-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 11/03/2013] [Indexed: 10/25/2022]
Abstract
Water exchange reactions of the complexes Al(H₂O)₅(L)]²⁺·H₂O for L = →OCN⁻, F⁻, CF₃⁻, →NC⁻, →CN⁻, Cl⁻, Br⁻, H⁻, SH⁻, OH⁻, →NCO⁻, →NCS⁻, →SCN⁻, CF₃CH₂⁻, CH₃⁻, Et⁻, i-Pr⁻ and t-but⁻, were studied by DFT calculations (B3LYP/6-311+G**). The reactions follow a dissociative (D) pathway for Al(H₂O)₅(L)]²⁺·H₂O to form the five-coordinate intermediate [Al(H₂O)₄L]²⁺·2H₂O for the weaker donor ligands of the series. On increasing the donor strength of L, the five-coordinate intermediate becomes significantly more stable than the reactant state. At this point there is a mechanistic changeover to an associative (A) pathway for [Al(H₂O)₄L]²⁺·2H₂O as reactant to form a six-coordinate intermediate Al(H₂O)₅(L)]²⁺·H₂O. For some of the anionic ligands L = → NC⁻, →CN⁻, Cl⁻, OH⁻ and →SCN⁻) the energy gap between the reactant and intermediate states is small, such that the water exchange mechanism lies in the boarder of dissociative and associative pathways. The water exchange process involves cis- and trans-orientated transition states to form the product state that is similar to the reactant state.
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36
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Warżajtis B, Rychlewska U, Radanović DD, Stanojević IM, Drašković NS, Radulović NS, Djuran MI. Carboxylato-bridged polymeric complexes of chromium(III) with the hexadentate (±)-1,3-pentanediamine-N,N,N′,N′-tetraacetate ligand carrying different counter ions. Stereospecific formation and crystal structures of Na[Cr(1,3-pndta)]·H2O, K[Cr(1,3-pndta)]·H2O and Ca[Cr(1,3-pndta)]2·4H2O. Polyhedron 2014. [DOI: 10.1016/j.poly.2013.09.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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37
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Esteban-Gómez D, Cassino C, Botta M, Platas-Iglesias C. 17O and 1H relaxometric and DFT study of hyperfine coupling constants in [Mn(H2O)6]2+. RSC Adv 2014. [DOI: 10.1039/c3ra45721d] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Gale EM, Zhu J, Caravan P. Direct measurement of the Mn(II) hydration state in metal complexes and metalloproteins through 17O NMR line widths. J Am Chem Soc 2013; 135:18600-8. [PMID: 24088013 DOI: 10.1021/ja4094132] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Here we describe a simple method to estimate the inner-sphere hydration state of the Mn(II) ion in coordination complexes and metalloproteins. The line width of bulk H2(17)O is measured in the presence and absence of Mn(II) as a function of temperature, and transverse (17)O relaxivities are calculated. It is demonstrated that the maximum (17)O relaxivity is directly proportional to the number of inner-sphere water ligands (q). Using a combination of literature data and experimental data for 12 Mn(II) complexes, we show that this method provides accurate estimates of q with an uncertainty of ±0.2 water molecules. The method can be implemented on commercial NMR spectrometers working at fields of 7 T and higher. The hydration number can be obtained for micromolar Mn(II) concentrations. We show that the technique can be extended to metalloproteins or complex:protein interactions. For example, Mn(II) binds to the multimetal binding site A on human serum albumin with two inner-sphere water ligands that undergo rapid exchange (1.06 × 10(8) s(-1) at 37 °C). The possibility of extending this technique to other metal ions such as Gd(III) is discussed.
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Affiliation(s)
- Eric M Gale
- The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital , Harvard Medical School , 149 Thirteenth Street, Suite 2301, Charlestown, Massachusetts 02129, United States
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Babailov SP, Stabnikov PA, Zapolotsky EN, Kokovkin VV. Lanthanides as NMR Probes of Fast Molecular Dynamics at High Magnetic Fields and Temperature Sensors: Conformational Interconversion of Erbium Ethylenediaminetetraacetate Complexes. Inorg Chem 2013; 52:5564-9. [DOI: 10.1021/ic400525r] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sergey P. Babailov
- A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences,
Av. Lavrentyev 3, Novosibirsk 630090, Russian Federation
| | - Pavel A. Stabnikov
- A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences,
Av. Lavrentyev 3, Novosibirsk 630090, Russian Federation
| | - Eugeny N. Zapolotsky
- A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences,
Av. Lavrentyev 3, Novosibirsk 630090, Russian Federation
| | - Vasily V. Kokovkin
- A. V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences,
Av. Lavrentyev 3, Novosibirsk 630090, Russian Federation
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40
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Rolla GA, Platas-Iglesias C, Botta M, Tei L, Helm L. 1H and 17O NMR relaxometric and computational study on macrocyclic Mn(II) complexes. Inorg Chem 2013; 52:3268-79. [PMID: 23437979 DOI: 10.1021/ic302785m] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Herein we report a detailed 1H and 17O relaxometric investigation of Mn(II) complexes with cyclen-based ligands such as 2-(1,4,7,10-tetraazacyclododecan-1-yl)acetic acid (DO1A), 2,2'-(1,4,7,10-tetraazacyclododecane-1,4-diyl)diacetic acid (1,4-DO2A), 2,2'-(1,4,7,10-tetraazacyclododecane-1,7-diyl)diacetic acid (1,7-DO2A), and 2,2',2"-(1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid (DO3A). The Mn(II) complex with the heptadentate ligand DO3A does not have inner sphere water molecules (q = 0), and therefore, the metal ion is most likely seven-coordinate. The hexadentate DO2A ligand has two isomeric forms: 1,7-DO2A and 1,4-DO2A. The Mn(II) complex with 1,7-DO2A is predominantly six-coordinate (q = 0). In aqueous solutions of [Mn(1,4-DO2A)], a species with one coordinated water molecule (q = 1) prevails largely, whereas a q = 0 form represents only about 10% of the overall population. The Mn(II) complex of the pentadentate ligand DO1A also contains a coordinated water molecule. DFT calculations (B3LYP model) are used to obtain information about the structure of this family of closely related complexes in solution, as well as to determine theoretically the 17O and 1H hyperfine coupling constants responsible for the scalar contribution to 17O and 1H NMR relaxation rates and 17O NMR chemical shifts. These calculations provide 17O A/ħ values of ca. 40 × 10(6) rad s(-1), in good agreement with experimental data. The [Mn(1,4-DO2A)(H2O)] complex is endowed with a relatively fast water exchange rate (k(ex)298 = 11.3 × 10(8) s(-1)) in comparison to the [Mn(EDTA)(H2O)]2- analogue (k(ex)298 = 4.7 × 10(8) s(-1)), but about 5 times lower than that of the [Mn(DO1A)(H2O)]+ complex (k(ex)298 = 60 × 10(8) s(-1)). The water exchange rate measured for the latter complex represents the highest water exchange rate ever measured for a Mn(II) complex.
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Affiliation(s)
- Gabriele A Rolla
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale Amedeo Avogadro, Viale T. Michel 11, 15121, Alessandria, Italy
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41
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de Sá A, Bonnet CS, Geraldes CFGC, Tóth É, Ferreira PMT, André JP. Thermodynamic stability and relaxation studies of small, triaza-macrocyclic Mn(ii) chelates. Dalton Trans 2013; 42:4522-32. [DOI: 10.1039/c2dt32496b] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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42
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Lieb D, Friedel FC, Yawer M, Zahl A, Khusniyarov MM, Heinemann FW, Ivanović-Burmazović I. Dinuclear Seven-Coordinate Mn(II) Complexes: Effect of Manganese(II)-Hydroxo Species on Water Exchange and Superoxide Dismutase Activity. Inorg Chem 2012; 52:222-36. [DOI: 10.1021/ic301714d] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Dominik Lieb
- Department
of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstr.
1, 91058 Erlangen, Germany
| | - Felix C. Friedel
- Department
of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstr.
1, 91058 Erlangen, Germany
| | - Mirza Yawer
- Department
of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstr.
1, 91058 Erlangen, Germany
| | - Achim Zahl
- Department
of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstr.
1, 91058 Erlangen, Germany
| | - Marat M. Khusniyarov
- Department
of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstr.
1, 91058 Erlangen, Germany
| | - Frank W. Heinemann
- Department
of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstr.
1, 91058 Erlangen, Germany
| | - Ivana Ivanović-Burmazović
- Department
of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Egerlandstr.
1, 91058 Erlangen, Germany
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43
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Babailov SP. Intermolecular dynamics and paramagnetic properties of ethylenediaminetetraacetate complexes with the yttrium subgroup rare earth elements using nuclear magnetic resonance. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2012; 50:793-797. [PMID: 23108837 DOI: 10.1002/mrc.3884] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 08/23/2012] [Accepted: 08/29/2012] [Indexed: 06/01/2023]
Abstract
(1)H nuclear magnetic resonance (NMR) measurements are reported for the D(2)O solutions of [Ln(3+)(EDTA(4-))](-) complexes, where EDTA(4-) is ethylenediaminetetraacetate anion, Ln(3+) = Tb(3+) (I), Ho(3+) (II), Tm(3+) (III), Yb(3+) (IV) and Lu(3+) (V). Temperature dependencies of the (1)H NMR spectra of paramagnetic I-IV have been analyzed using the dynamic NMR methods. It is found that the activation free energies (ΔG(‡)(298)) of the intermolecular EDTA ions exchange at [Ln(3+) (EDTA(4-))](-) complexes are 60±3 (I), 66±3 (II), 69±3 (III) and 74±3 (IV) kJ/mol (at pD = 7). A monotonic increase of the free energy of chemical exchange processes along the series of lanthanide [Ln(3+) (EDTA(4-))](-) complexes is probably related to the lanthanide contraction. The obtained results indicate that coordination compounds I-IV may be considered as thermometric NMR sensors and lanthanide paramagnetic probes for in situ temperature control in solution.
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Affiliation(s)
- Sergey P Babailov
- A.V. Nikolaev's Institute of Inorganic Chemistry SB RAS, Av. Lavrentyev, 3, Novosibirsk, 630090, Russia.
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44
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Drahoš B, Lukeš I, Tóth É. Manganese(II) Complexes as Potential Contrast Agents for MRI. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201101336] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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45
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Forgács A, Giovenzana GB, Botta M, Brücher E, Tóth I, Baranyai Z. Influence of
gem
‐Dimethyl Substitution on the Stability, Kinetics and Relaxometric Properties of PDTA Complexes. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201101294] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Attila Forgács
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem tér 1, 4010 Debrecen, Hungary, Fax: +36‐52‐518‐660
- Dipartimento di Scienze dell'Ambiente e della Vita (DISAV), Università degli Studi del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Giovanni B. Giovenzana
- Dipartimento di Scienze Chimiche, Alimentari, Farmaceutiche e Farmacologiche (DiSCAFF), Università del Piemonte Orientale “A. Avogadro”, Via Bovio 6, 28100 Novara, Italy
| | - Mauro Botta
- Dipartimento di Scienze dell'Ambiente e della Vita (DISAV), Università degli Studi del Piemonte Orientale “A. Avogadro”, Viale T. Michel 11, 15121 Alessandria, Italy
| | - Ernő Brücher
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem tér 1, 4010 Debrecen, Hungary, Fax: +36‐52‐518‐660
| | - Imre Tóth
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem tér 1, 4010 Debrecen, Hungary, Fax: +36‐52‐518‐660
| | - Zsolt Baranyai
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem tér 1, 4010 Debrecen, Hungary, Fax: +36‐52‐518‐660
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46
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Zhang CH, Chen YG, Tang Q, Liu SX. Polynuclear complexes of main group and transition metals with polyaminopolycarboxylate and polyoxometalate. Dalton Trans 2012; 41:9971-8. [DOI: 10.1039/c2dt12508k] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Drahoš B, Kotek J, Cı́sařová I, Hermann P, Helm L, Lukeš I, Tóth É. Mn2+ Complexes with 12-Membered Pyridine Based Macrocycles Bearing Carboxylate or Phosphonate Pendant Arm: Crystallographic, Thermodynamic, Kinetic, Redox, and 1H/17O Relaxation Studies. Inorg Chem 2011; 50:12785-801. [DOI: 10.1021/ic201935r] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bohuslav Drahoš
- Department of Inorganic Chemistry,
Faculty of Science, Universita Karlova (Charles
University), Hlavova 2030, 128 43 Prague 2, Czech Republic
- Centre de Biophysique Moléculaire, CNRS, rue Charles Sadron, 45071 Orléans, France
| | - Jan Kotek
- Department of Inorganic Chemistry,
Faculty of Science, Universita Karlova (Charles
University), Hlavova 2030, 128 43 Prague 2, Czech Republic
| | - Ivana Cı́sařová
- Department of Inorganic Chemistry,
Faculty of Science, Universita Karlova (Charles
University), Hlavova 2030, 128 43 Prague 2, Czech Republic
| | - Petr Hermann
- Department of Inorganic Chemistry,
Faculty of Science, Universita Karlova (Charles
University), Hlavova 2030, 128 43 Prague 2, Czech Republic
| | - Lothar Helm
- Ecole Polytechnique Fédérale de Lausanne, BCH, Lausanne, Switzerland
| | - Ivan Lukeš
- Department of Inorganic Chemistry,
Faculty of Science, Universita Karlova (Charles
University), Hlavova 2030, 128 43 Prague 2, Czech Republic
| | - Éva Tóth
- Centre de Biophysique Moléculaire, CNRS, rue Charles Sadron, 45071 Orléans, France
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48
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Xue Z, Daran JC, Champouret Y, Poli R. Ligand Adducts of Bis(acetylacetonato)iron(II): A 1H NMR Study. Inorg Chem 2011; 50:11543-51. [DOI: 10.1021/ic201486v] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhigang Xue
- LCC (Laboratoire de
Chimie de
Coordination), Université de Toulouse, UPS, INP, 205, route de Narbonne, F-31077 Toulouse, France
| | - Jean-Claude Daran
- LCC (Laboratoire de
Chimie de
Coordination), Université de Toulouse, UPS, INP, 205, route de Narbonne, F-31077 Toulouse, France
| | - Yohan Champouret
- LCC (Laboratoire de
Chimie de
Coordination), Université de Toulouse, UPS, INP, 205, route de Narbonne, F-31077 Toulouse, France
| | - Rinaldo Poli
- LCC (Laboratoire de
Chimie de
Coordination), Université de Toulouse, UPS, INP, 205, route de Narbonne, F-31077 Toulouse, France
- Institut Universitaire de France, 103, bd Saint-Michel, 75005 Paris, France
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49
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Drahoš B, Pniok M, Havlíčková J, Kotek J, Císařová I, Hermann P, Lukeš I, Tóth E. Mn2+ complexes of 1-oxa-4,7-diazacyclononane based ligands with acetic, phosphonic and phosphinic acid pendant arms: stability and relaxation studies. Dalton Trans 2011; 40:10131-46. [PMID: 21887440 DOI: 10.1039/c1dt10543d] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new class of macrocyclic ligands based on 1-oxa-4,7-diazacyclononane was synthesized and their Mn(2+) complexes were investigated with respect to stability and relaxation properties. Each ligand has two pendant arms involving carboxylic (H(2)L(1)--1-oxa-4,7-diazacyclononane-4,7-diacetic acid), phosphonic (H(4)L(2)--1-oxa-4,7-diazacyclononane-4,7-bis(methylenephosphonic acid)), phosphinic (H(2)L(3)--1-oxa-4,7-diazacyclononane-4,7-bis(methylenephosphinic acid)) or phenylphosphinic (H(2)L(4)--1-oxa-4,7-diazacyclononane-4,7-bis[methylene(phenyl)phosphinic acid]) acid moieties. H(2)L(3) and H(2)L(4) were synthesized for the first time. The crystal structure of the Mn(2+) complex with H(2)L(4) confirmed a coordination number of 6 for Mn(2+). The protonation constants of all ligands and the stability constants of their complexes with Mn(2+) and some biologically or biomedically relevant metal ions were determined by potentiometry. The protonation sequence of H(2)L(3) was followed by (1)H and (31)P NMR titration and the second protonation step was attributed to the second macrocyclic nitrogen atom. The potentiometric data revealed a relatively low thermodynamic stability of the Mn(2+) complexes with all ligands investigated. For H(2)L(3) and H(2)L(4), full Mn(2+) complexation cannot be achieved even with 100% ligand excess. The transmetallation of MnL(1) and MnL(2) with Zn(2+) was too fast to be followed at pH 6. Variable temperature (1)H NMRD and (17)O NMR measurements have been performed on MnL(1) and MnL(2) to provide information on water exchange and rotational dynamics. The (17)O chemical shifts indicate hydration equilibrium between mono- and bishydrated species for MnL(1), while MnL(2) is monohydrated. The water exchange is considerably faster on MnL(1) (k(ex)(298) = 1.2 × 10(9) s(-1)) than on MnL(2) (k(ex)(298) = 1.2 × 10(7) s(-1)). Small endogenous anions (phosphate, carbonate, citrate) do not replace the coordinated water in either of the complexes, but they induce their slow decomposition. All Mn(2+) complexes are stable toward air-oxidation.
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Affiliation(s)
- Bohuslav Drahoš
- Department of Inorganic Chemistry, Faculty of Science, Universita Karlova (Charles University), Hlavova, 2030, 128 43, Prague 2, Czech Republic
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50
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Tei L, Gugliotta G, Fekete M, Kálmán FK, Botta M. Mn(ii) complexes of novel hexadentate AAZTA-like chelators: a solution thermodynamics and relaxometric study. Dalton Trans 2011; 40:2025-32. [DOI: 10.1039/c0dt01114b] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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