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Caillet E, Nunes L, Eliseeva SV, Ndiaye M, Isaac M, Pallier A, Morfin JF, Meudal H, Petoud S, Routier S, Platas-Iglesias C, Buron F, Bonnet CS. Investigation of Ln 3+ complexation by a DOTA derivative substituted by an imidazothiadiazole: synthesis, solution structure, luminescence and relaxation properties. Dalton Trans 2024; 53:9028-9041. [PMID: 38726882 DOI: 10.1039/d4dt00533c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
We investigated the coordination properties of original macrocyclic Ln3+ complexes comprising an imidazothiadiazole heterocycle. The thermodynamic stability of the Gd3+ complex was determined by a combination of potentiometric and photophysical measurements. The kinetic inertness was assessed in highly acidic media. The solution structure of the Ln3+ complex was unambiguously determined by a set of photophysical measurements and 1H, 13C, 89Y NMR data in combination with DFT calculations, which proved coordination of the heterocycle to Ln3+. The ability of the imidazothiadiazole moiety to sensitize Tb3+ luminescence was investigated. Finally, the relaxation properties were investigated by recording 1H nuclear magnetic relaxation dispersion (NMRD) profiles and 17O measurements. The water exchange rate is similar to that of GdDOTA as the less negative charge of the ligand is compensated for by the presence of a bulky heterocycle. Relaxivity is constant over a large range of pH values, demonstrating the favorable properties of the complex for imaging purposes.
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Affiliation(s)
- Emma Caillet
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
- Institut de Chimie Organique et Analytique UMR CNRS 7311, Université d'Orléans, Rue de Chartres, BP6759, 45067 Orléans Cedex 2, France.
| | - Léa Nunes
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
- Institut de Chimie Organique et Analytique UMR CNRS 7311, Université d'Orléans, Rue de Chartres, BP6759, 45067 Orléans Cedex 2, France.
| | - Svetlana V Eliseeva
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
| | - Modou Ndiaye
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
- Institut de Chimie Organique et Analytique UMR CNRS 7311, Université d'Orléans, Rue de Chartres, BP6759, 45067 Orléans Cedex 2, France.
| | - Manon Isaac
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
| | - Agnès Pallier
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
| | - Jean-François Morfin
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
| | - Hervé Meudal
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
| | - Stéphane Petoud
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
| | - Sylvain Routier
- Institut de Chimie Organique et Analytique UMR CNRS 7311, Université d'Orléans, Rue de Chartres, BP6759, 45067 Orléans Cedex 2, France.
| | - Carlos Platas-Iglesias
- Universidade da Coruña, Centro de Interdisciplinar de Química e Bioloxía (CICA) and Departamento de Química, Facultade de Ciencias, 15071, A Coruña, Galicia, Spain
| | - Frédéric Buron
- Institut de Chimie Organique et Analytique UMR CNRS 7311, Université d'Orléans, Rue de Chartres, BP6759, 45067 Orléans Cedex 2, France.
| | - Célia S Bonnet
- Centre de Biophysique Moléculaire CNRS UPR 4301, Université d'Orléans, Rue Charles Sadron, 45071 Orléans Cedex 2, France.
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2
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Kanal E, Maki JH, Schramm P, Marti-Bonmati L. Evolving Characteristics of Gadolinium-Based Contrast Agents for MR Imaging: A Systematic Review of the Importance of Relaxivity. J Magn Reson Imaging 2024. [PMID: 38699938 DOI: 10.1002/jmri.29367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 03/15/2024] [Accepted: 03/15/2024] [Indexed: 05/05/2024] Open
Abstract
Gadolinium-based contrast agents (GBCAs) are widely and routinely used to enhance the diagnostic performance of magnetic resonance imaging and magnetic resonance angiography examinations. T1 relaxivity (r1) is the measure of their ability to increase signal intensity in tissues and blood on T1-weighted images at a given dose. Pharmaceutical companies have invested in the design and development of GBCAs with higher and higher T1 relaxivity values, and "high relaxivity" is a claim frequently used to promote GBCAs, with no clear definition of what "high relaxivity" means, or general concurrence about its clinical benefit. To understand whether higher relaxivity values translate into a material clinical benefit, well-designed, and properly powered clinical studies are necessary, while mere in vitro measurements may be misleading. This systematic review of relevant peer-reviewed literature provides high-quality clinical evidence showing that a difference in relaxivity of at least 40% between two GBCAs results in superior diagnostic efficacy for the higher-relaxivity agent when this is used at the same equimolar gadolinium dose as the lower-relaxivity agent, or similar imaging performance when used at a lower dose. Either outcome clearly implies a relevant clinical benefit. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.
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Affiliation(s)
- Emanuel Kanal
- Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
- Division of Emergency Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Jeffrey H Maki
- Department of Radiology, University of Colorado Anschutz Medical Center, Aurora, Colorado, USA
| | - Peter Schramm
- Department of Neuroradiology, University Luebeck and Universitaetsklinikum Schleswig-Holstein Campus Luebeck, Luebeck, Germany
| | - Luis Marti-Bonmati
- Department of Radiology and GIBI230 Research Group on Biomedical Imaging, Hospital Universitario y Politécnico de La Fe and Instituto de Investigación Sanitaria La Fe, Valencia, Spain
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3
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Nizou G, Garda Z, Molnár E, Esteban-Gómez D, Le Fur M, Fougère O, Rousseaux O, Platas-Iglesias C, Tripier R, Tircsó G, Beyler M. Exploring the Limits of Ligand Rigidification in Transition Metal Complexes with Mono- N-Functionalized Pyclen Derivatives. Inorg Chem 2024; 63:3931-3947. [PMID: 38348851 DOI: 10.1021/acs.inorgchem.3c04451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
We report the synthesis of a new family of side-bridged pyclen ligands. The incorporation of an ethylene bridge between two adjacent nitrogen atoms was reached from the pyclen-oxalate precursor described previously. Three new side-bridged pyclen macrocycles, Hsb-3-pc1a, sb-3-pc1py, and Hsb-3-pc1pa, were obtained with the aim to assess their coordination properties toward Cu2+ and Zn2+ ions. We also prepared their nonreinforced analogues H3-pc1a, 3-pc1py, and H3-pc1pa as comparative benchmarks. The two series of ligands were characterized and their coordination properties were investigated in detail. The Zn2+ and Cu2+ complexes with the nonside-bridged series H3-pc1a, 3-pc1py, and H3-pc1pa were successfully isolated and their structures were assessed by X-ray diffraction studies. In the case of the side-bridged family, the synthesis of the complexes was far more difficult and, in some cases, unsuccessful. The results of our studies demonstrate that this difficulty is related to the extreme stiffening and basicity of such side-bridged pyclens.
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Affiliation(s)
- Gwladys Nizou
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor Le Gorgeu, Brest 29200, France
| | - Zoltán Garda
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | - Enikő Molnár
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | - David Esteban-Gómez
- Centro Interdisciplinar de Química e Bioloxía (CICA) and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Mariane Le Fur
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor Le Gorgeu, Brest 29200, France
| | - Olivier Fougère
- Groupe Guerbet, Centre de Recherche d'Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - Olivier Rousseaux
- Groupe Guerbet, Centre de Recherche d'Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - Carlos Platas-Iglesias
- Centro Interdisciplinar de Química e Bioloxía (CICA) and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Raphaël Tripier
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor Le Gorgeu, Brest 29200, France
| | - Gyula Tircsó
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | - Maryline Beyler
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor Le Gorgeu, Brest 29200, France
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Hamon N, Godec L, Jourdain E, Lucio-Martínez F, Platas-Iglesias C, Beyler M, Charbonnière LJ, Tripier R. Synthesis and Photophysical Properties of Lanthanide Pyridinylphosphonic Tacn and Pyclen Derivatives: From Mononuclear Complexes to Supramolecular Heteronuclear Assemblies. Inorg Chem 2023; 62:18940-18954. [PMID: 37935007 DOI: 10.1021/acs.inorgchem.3c02522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
Synthetic methodologies were developed to achieve the preparation of ligands L1 and L2 consisting of tacn- and pyclen-based chelators decorated with pyridinylphosphonic pendant arms combined with ethylpicolinamide or acetate coordinating functions, respectively. Phosphonate functions have been selected for their high affinity toward Ln3+ ions compared to their carboxylated counterparts and for their steric hindrance that favors the formation of less-hydrated complexes. Thanks to regiospecific N-functionalization of the macrocyclic backbones, the two ligands were isolated with good yields and implicated in a comprehensive photophysical study for the complexation of Eu3+, Tb3+, and Yb3+. The coordination behavior of L1 and L2 with these cations has been first investigated by means of a combination of UV-vis absorption spectroscopy, steady-state and time-resolved luminescence spectroscopy, and 1H and 31P NMR titration experiments. Structural characterization in solution was assessed by NMR spectroscopy, corroborated by theoretical calculations. Spectroscopic characterization of the Ln3+ complexes of L1 and L2 was done in water and D2O and showed the effective sensitization of the lanthanide metal-centered emission spectra, each exhibiting typical lanthanide emission bands. The results obtained for the phosphonated ligands were compared with those reported previously for the corresponding carboxylated analogues.
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Affiliation(s)
- Nadège Hamon
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor Le Gorgeu, Brest 29200, France
| | - Léna Godec
- Equipe de Synthèse pour l'analyse, Institut Pluridisciplinaire Hubert Curien, UMR 7178, CNRS/Université de Strasbourg, ECPM, 25 rue Becquerel, Strasbourg 67087, Cedex 2, France
| | - Elsa Jourdain
- Equipe de Synthèse pour l'analyse, Institut Pluridisciplinaire Hubert Curien, UMR 7178, CNRS/Université de Strasbourg, ECPM, 25 rue Becquerel, Strasbourg 67087, Cedex 2, France
| | - Fátima Lucio-Martínez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, A Coruña 15008, Spain
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, A Coruña 15008, Spain
| | - Maryline Beyler
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor Le Gorgeu, Brest 29200, France
| | - Loïc J Charbonnière
- Equipe de Synthèse pour l'analyse, Institut Pluridisciplinaire Hubert Curien, UMR 7178, CNRS/Université de Strasbourg, ECPM, 25 rue Becquerel, Strasbourg 67087, Cedex 2, France
| | - Raphaël Tripier
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor Le Gorgeu, Brest 29200, France
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5
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Hamon N, Bridou L, Roux M, Maury O, Tripier R, Beyler M. Design of Bifunctional Pyclen-Based Lanthanide Luminescent Bioprobes for Targeted Two-Photon Imaging. J Org Chem 2023; 88:8286-8299. [PMID: 37273214 DOI: 10.1021/acs.joc.3c00287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In the past, Lanthanide Luminescent Bioprobes (LLBs) based on pyclen-bearing π-extended picolinate antennas were synthesized and demonstrated well-adapted optical properties for biphotonic microscopy. The objective of this work is to develop a strategy to design bifunctional analogues of the previously studied LLBs presenting an additional reactive chemical group to allow their coupling to biological vectors to reach deep in vivo targeted two-photon bioimaging. Herein, we elaborated a synthetic scheme allowing the introduction of a primary amine on the para position of the macrocyclic pyridine unit. The photophysical and bioimaging studies demonstrate that the introduction of the reactive function does not alter the luminescent properties of the LLBs paving the way for further applications.
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Affiliation(s)
- Nadège Hamon
- Univ Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 BREST, France
| | - Lucile Bridou
- Univ Lyon, ENS de Lyon, CNRS UMR 5182, Laboratoire de Chimie, Lyon F-69342, France
| | - Margaux Roux
- Univ Lyon, ENS de Lyon, CNRS UMR 5182, Laboratoire de Chimie, Lyon F-69342, France
| | - Olivier Maury
- Univ Lyon, ENS de Lyon, CNRS UMR 5182, Laboratoire de Chimie, Lyon F-69342, France
| | - Raphaël Tripier
- Univ Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 BREST, France
| | - Maryline Beyler
- Univ Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 BREST, France
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6
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Mekhail MA, Pota K, Kharel S, Freire DM, Green KN. Pyridine modifications regulate the electronics and reactivity of Fe-pyridinophane complexes. Dalton Trans 2023; 52:892-901. [PMID: 36537287 PMCID: PMC10903111 DOI: 10.1039/d2dt03485a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
12-Membered pyridinophanes are the focus of many studies as biological mimics, chelators, and catalytic precursors. Therefore, the desire to tune the reactivity of pyridinophanes to better control the applications of derivative metal complexes has inspired many structure-activity relationship studies. However, the separation of structural versus electronic changes imparted by ligand modification has made these structure-activity relationship studies of transition metal catalysts challenging to define. In this work we show that 4-substitution of the pyridine ring in 12-membered tetra-aza pyridinophanes successfully provides a regulatory handle on the electronic properties of the metal center and, therefore, the catalytic C-C coupling activity of the respective iron complexes. The C-C coupling reaction catalyzed by Fe(L1-L6) provides a range of yields (32-58%) that directly correlate with iron redox potentials (ΔE1/2 = 152 mV) and metal binding constants (Δlog β = 3.45), while the geometry of the complexes was virtually indistinguishable. These are the first results to definitively show the redox potential and metal binding as independent properties from the coordination chemistry in one ligand series. Adjustments to these chemical properties were then shown to provide a regulatory handle for the C-C coupling reactivity tuned via pyridine substitution in pyridinophanes.
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Affiliation(s)
- Magy A Mekhail
- Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, Texas 76129, USA.
| | - Kristof Pota
- Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, Texas 76129, USA.
| | - Sugam Kharel
- Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, Texas 76129, USA.
| | - David M Freire
- Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, Texas 76129, USA.
| | - Kayla N Green
- Department of Chemistry and Biochemistry, Texas Christian University, Fort Worth, Texas 76129, USA.
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7
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Uzal-Varela R, Rodríguez-Rodríguez A, Wang H, Esteban-Gómez D, Brandariz I, Gale EM, Caravan P, Platas-Iglesias C. Prediction of Gd(III) complex thermodynamic stability. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214606] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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8
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Váradi B, Lihi N, Bunda S, Nagy A, Simon G, Kéri M, Papp G, Tircsó G, Esteban-Gómez D, Platas-Iglesias C, Kálmán FK. Physico-Chemical Characterization of a Highly Rigid Gd(III) Complex Formed with a Phenanthroline Derivative Ligand. Inorg Chem 2022; 61:13497-13509. [PMID: 35972786 DOI: 10.1021/acs.inorgchem.2c02050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The discovery of the nephrogenic systemic fibrosis (NSF) and its link with the in vivo dissociation of certain Gd(III)-based contrast agents (CAs) applied in the magnetic resonance imaging (MRI) induced a still growing research to replace the compromised agents with safer alternatives. In recent years, several ligands were designed to exploit the luminescence properties of the lanthanides, containing structurally constrained aromatic moieties, which may form rigid Gd(III) complexes. One of these ligands is (1,10-phenanthroline-2,9-diyl)bis(methyliminodiacetic acid) (H4FENTA) designed and synthesized to sensitize Eu(III) and Tb(III) luminescence. Our results show that the conditional stability of the [Gd(FENTA)]- chelate calculated for physiological pH (pGd = 19.7) is similar to those determined for [Gd(DTPA)]2- (pGd = 19.4) and [Gd(DOTA)]- (pGd = 20.1), routinely used in the clinical practice. The [Gd(FENTA)]- complex is remarkably inert with respect to its dissociation (t1/2 = 872 days at pH = 7 and 25 °C); furthermore, its relaxivity values determined at different field strengths and temperatures (e.g., r1p = 4.3 mM-1s-1at 60 MHz and 37 °C) are ca. one unit higher than those of [Gd(DTPA)]2- (r1p = 3.4 mM-1 s-1) and [Gd(DOTA)]- (r1p = 3.1 mM-1 s-1) under the same conditions. Moreover, significant improvement on the relaxivity was observed in the presence of serum proteins (r1p = 6.9 mM-1 s-1 at 60 MHz and 37 °C). The luminescence lifetimes recorded in H2O and D2O solutions indicate the presence of a water molecule (q = 1) in the inner sphere of the complex directly coordinated to the metal ion, possessing a relatively high water exchange rate (kex298 = 29(2) × 106 s-1). The acceleration of the water exchange can be explained by the steric compression around the water binding site due to the rigid structure of the complex, which was supported by DFT calculations. On the basis of these results, ligands containing a phenanthroline platform have great potential in the design of safer Gd(III) agents for MRI.
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Affiliation(s)
- Balázs Váradi
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary.,Doctoral School of Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, Debrecen H-4032, Hungary
| | - Norbert Lihi
- ELKH-DE Mechanisms of Complex Homogeneous and Heterogeneous Chemical Reactions Research Group, Department of Inorganic and Analytical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary
| | - Szilvia Bunda
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary
| | - Antónia Nagy
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary
| | - Gréta Simon
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary
| | - Mónika Kéri
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary
| | - Gábor Papp
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary
| | - Gyula Tircsó
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary
| | - David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Univer-sidade da Coruña, A Coruña, Galicia 15071, Spain
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Univer-sidade da Coruña, A Coruña, Galicia 15071, Spain
| | - Ferenc K Kálmán
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Debrecen H-4032, Hungary
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9
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Harriswangler C, Caneda-Martínez L, Rousseaux O, Esteban-Gómez D, Fougère O, Pujales-Paradela R, Valencia L, Fernández MI, Lepareur N, Platas-Iglesias C. Versatile Macrocyclic Platform for the Complexation of [ natY/ 90Y]Yttrium and Lanthanide Ions. Inorg Chem 2022; 61:6209-6222. [PMID: 35418232 PMCID: PMC9044452 DOI: 10.1021/acs.inorgchem.2c00378] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Indexed: 11/29/2022]
Abstract
We report a macrocyclic ligand (H3L6) based on a 3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane platform containing three acetate pendant arms and a benzyl group attached to the fourth nitrogen atom of the macrocycle. The X-ray structures of the YL6 and TbL6 complexes reveal nine coordination of the ligand to the metal ions through the six nitrogen atoms of the macrocycle and three oxygen atoms of the carboxylate pendants. A combination of NMR spectroscopic studies (1H, 13C, and 89Y) and DFT calculations indicated that the structure of the YL6 complex in the solid state is maintained in an aqueous solution. The detailed study of the emission spectra of the EuL6 and TbL6 complexes revealed Ln3+-centered emission with quantum yields of 7.0 and 60%, respectively. Emission lifetime measurements indicate that the ligand offers good protection of the metal ions from surrounding water molecules, preventing the coordination of water molecules. The YL6 complex is remarkably inert with respect to complex dissociation, with a lifetime of 1.7 h in 1 M HCl. On the other hand, complex formation is fast (∼1 min at pH 5.4, 2 × 10-5 M). Studies using the 90Y-nuclide confirmed fast radiolabeling since [90Y]YL6 is nearly quantitatively formed (radiochemical yield (RCY) > 95) in a short time over a broad range of pH values from ca. 2.4 to 9.0. Challenging experiments in the presence of excess ethylenediaminetetraacetic acid (EDTA) and in human serum revealed good stability of the [90Y]YL6 complex. All of these experiments combined suggest the potential application of H3L6 derivatives as Y-based radiopharmaceuticals.
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Affiliation(s)
- Charlene Harriswangler
- Centro
de Investigacións Científicas Avanzadas (CICA) and Departamento
de Química, Facultade de Ciencias, Universidade da Coruña, 15071 Galicia, A Coruña, Spain
| | - Laura Caneda-Martínez
- Centro
de Investigacións Científicas Avanzadas (CICA) and Departamento
de Química, Facultade de Ciencias, Universidade da Coruña, 15071 Galicia, A Coruña, Spain
| | - Olivier Rousseaux
- Groupe
Guerbet, Centre de Recherche d’Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - David Esteban-Gómez
- Centro
de Investigacións Científicas Avanzadas (CICA) and Departamento
de Química, Facultade de Ciencias, Universidade da Coruña, 15071 Galicia, A Coruña, Spain
| | - Olivier Fougère
- Groupe
Guerbet, Centre de Recherche d’Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - Rosa Pujales-Paradela
- Centro
de Investigacións Científicas Avanzadas (CICA) and Departamento
de Química, Facultade de Ciencias, Universidade da Coruña, 15071 Galicia, A Coruña, Spain
| | - Laura Valencia
- Departamento
de Química Inorgánica, Facultad de Ciencias, Universidade de Vigo, As Lagoas, Marcosende, 36310 Pontevedra, Spain
| | - M. Isabel Fernández
- Centro
de Investigacións Científicas Avanzadas (CICA) and Departamento
de Química, Facultade de Ciencias, Universidade da Coruña, 15071 Galicia, A Coruña, Spain
| | - Nicolas Lepareur
- Univ
Rennes, Centre Eugène Marquis, Inrae, Inserm, Institut NUMECAN
(Nutrition, Métabolismes et Cancer)—UMR_A 1341, UMR_S
1241, F-35000 Rennes, France
| | - Carlos Platas-Iglesias
- Centro
de Investigacións Científicas Avanzadas (CICA) and Departamento
de Química, Facultade de Ciencias, Universidade da Coruña, 15071 Galicia, A Coruña, Spain
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10
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Lucio-Martínez F, Garda Z, Váradi B, Kálmán FK, Esteban-Gómez D, Tóth É, Tircsó G, Platas-Iglesias C. Rigidified Derivative of the Non-macrocyclic Ligand H 4OCTAPA for Stable Lanthanide(III) Complexation. Inorg Chem 2022; 61:5157-5171. [PMID: 35275621 PMCID: PMC8965877 DOI: 10.1021/acs.inorgchem.2c00501] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
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The stability constants
of lanthanide complexes with the potentially
octadentate ligand CHXOCTAPA4–,
which contains a rigid 1,2-diaminocyclohexane scaffold functionalized
with two acetate and two picolinate pendant arms, reveal the formation
of stable complexes [log KLaL = 17.82(1)
and log KYbL = 19.65(1)]. Luminescence
studies on the Eu3+ and Tb3+ analogues evidenced
rather high emission quantum yields of 3.4 and 11%, respectively.
The emission lifetimes recorded in H2O and D2O solutions indicate the presence of a water molecule coordinated
to the metal ion. 1H nuclear magnetic relaxation dispersion
profiles and 17O NMR chemical shift and relaxation measurements
point to a rather low water exchange rate of the coordinated water
molecule (kex298 = 1.58 ×
106 s–1) and relatively high relaxivities
of 5.6 and 4.5 mM–1 s–1 at 20
MHz and 25 and 37 °C, respectively. Density functional theory
calculations and analysis of the paramagnetic shifts induced by Yb3+ indicate that the complexes adopt an unprecedented cis geometry
with the two picolinate groups situated on the same side of the coordination
sphere. Dissociation kinetics experiments were conducted by investigating
the exchange reactions of LuL occurring with Cu2+. The
results confirmed the beneficial effect of the rigid cyclohexyl group
on the inertness of the Lu3+ complex. Complex dissociation
occurs following proton- and metal-assisted pathways. The latter is
relatively efficient at neutral pH, thanks to the formation of a heterodinuclear
hydroxo complex. A
non-macrocyclic ligand containing a rigid cyclohexyl spacer
forms thermodynamically stable complexes with the lanthanide(III)
ions in aqueous solution. The complexes also show remarkable kinetic
inertness, though a structural change facilitates dissociation through
the metal-assisted mechanism for the small lanthanides. The Gd(III)
complex displays a relatively high relaxivity due to the presence
of a water molecule coordinated to the metal ion, while the Eu(III)
and Tb(III) analogues display strong metal-centered luminescence.
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Affiliation(s)
- Fátima Lucio-Martínez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Zoltán Garda
- Department of Physical Chemistry, University of Debrecen, Egyetem tér 1, H-4010 Debrecen, Hungary
| | - Balázs Váradi
- Department of Physical Chemistry, University of Debrecen, Egyetem tér 1, H-4010 Debrecen, Hungary.,Doctoral School of Chemistry, University of Debrecen, Egyetem tér 1, H-4010 Debrecen, Hungary
| | - Ferenc Krisztián Kálmán
- Department of Physical Chemistry, University of Debrecen, Egyetem tér 1, H-4010 Debrecen, Hungary
| | - David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, 15071 A Coruña, Galicia, Spain
| | - Éva Tóth
- Centre de Biophysique Moléculaire, CNRS UPR 4301, Université d'Orléans, rue Charles Sadron, 45071 Orléans, Cedex 2, France
| | - Gyula Tircsó
- Department of Physical Chemistry, University of Debrecen, Egyetem tér 1, H-4010 Debrecen, Hungary
| | - Carlos Platas-Iglesias
- 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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11
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Panza N, Tseberlidis G, Caselli A, Vicente R. Recent progresses in the chemistry of 12-membered pyridine-containing tetraazamacrocycles: From synthesis to catalysis. Dalton Trans 2022; 51:10635-10657. [DOI: 10.1039/d2dt00597b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This article provides an overview (non-comprehensive) on recent developments regarding pyridine-containing 12-membered tetraazamacrocycles with pyclen or Py2N2 backbones and their metal complexes from 2017 to the present. Firstly, the synthesis...
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12
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Leygue N, Picard C, Faure P, Bourrier E, Lamarque L, Zwier JM, Galaup C. Design of novel tripyridinophane-based Eu(III) complexes as efficient luminescent labels for bioassay applications. Org Biomol Chem 2021; 20:182-195. [PMID: 34878481 DOI: 10.1039/d1ob02092g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this work, the development of highly luminescent europium(III) complexes in water solution is reported, including their syntheses, analyses of their photophysical properties and applications in bioassays. Three Eu(III) complexes are derived from new ligands based on a tripyridinophane platform. There are four distinct sections in the structure of these ligands: an 18-membered polyaminocarboxylic macrocycle to bind efficiently lanthanide ions in aqueous solutions, three chromophoric subunits (4-(phenylethynyl)pyridine moieties) to effectively sensitize the emission of the metal, two peripheral moieties to solubilise the complex in aqueous media (sulfonate, sulfobetaine or glucose groups) and a free NH2 group available for grafting or bioconjugation. In our synthetic procedure, a pivotal macrocyclic platform is obtained with a high yield in the crucial macrocyclization step due to a metal template ion effect (74% yield). In Tris aqueous buffer (pH 7.4), the Eu(III) complexes show a maximum excitation wavelength at 320 nm, a suitable overall quantum yield (14%), a relatively long lifetime (0.80 ms) and a one-photon brightness in the range of 10 000 M-1 cm-1. Importantly, these photophysical properties are retained at dilute concentrations, even in the presence of a very large excess of potentially competing species, such as EDTA or Mg2+ ions. Furthermore, we report the bioconjugation of a Eu(III) complex labelled by an N-hydroxysuccinimide ester reactive group with an antibody (anti-glutathione-S-transferase) and the successful application of the corresponding antibody conjugate in the detection of GST-biotin in a fluoroimmunoassay. These new complexes provide a solution for high sensitivity in Homogeneous Time-Resolved Fluorescence (HTRF®) bioassays.
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Affiliation(s)
- Nadine Leygue
- SPCMIB, UMR5068 CNRS-Université Paul Sabatier-Toulouse III, 118 Route de Narbonne, F-31062 Toulouse, France.
| | - Claude Picard
- SPCMIB, UMR5068 CNRS-Université Paul Sabatier-Toulouse III, 118 Route de Narbonne, F-31062 Toulouse, France.
| | - Pamela Faure
- Cisbio Bioassays, BP 84175, 30200 Codolet, France.
| | | | | | | | - Chantal Galaup
- SPCMIB, UMR5068 CNRS-Université Paul Sabatier-Toulouse III, 118 Route de Narbonne, F-31062 Toulouse, France.
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13
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Le Fur M, Fougère O, Lepareur N, Rousseaux O, Tripier R, Beyler M. Tuning the lipophilic nature of pyclen-based 90Y3+ radiopharmaceuticals for β-radiotherapy. Metallomics 2021; 13:6445036. [PMID: 34850060 DOI: 10.1093/mtomcs/mfab070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/16/2021] [Indexed: 01/31/2023]
Abstract
Pyclen-dipicolinate chelates proved to be very efficient chelators for the radiolabeling with β--emitters such as 90Y. In this study, a pyclen-dipicolinate ligand functionalized with additional C12 alkyl chains was synthesized. The radiolabeling with 90Y proved that the addition of saturated carbon chains does not affect the efficiency of the radiolabeling, whereas a notable increase in lipophilicity of the resulting 90Y radiocomplex was observed. As a result, the compound could be extracted in Lipiodol® and encapsulated in biodegrable pegylated poly(malic acid) nanoparticles demonstrating the potential of lipophilic pyclen-dipicolinate derivatives as platforms for the design of radiopharmaceuticals for the treatment of liver or brain cancers by internal radiotherapy.
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Affiliation(s)
- Mariane Le Fur
- Univ Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
| | - Olivier Fougère
- Guerbet group, Centre de Recherche d'Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - Nicolas Lepareur
- Univ Rennes, Centre Eugène Marquis, Inrae, Inserm, Institut NUMECAN [(Nutrition, Métabolismes et Cancer)]-UMR_A 1341, UMR_S 1241, Avenue de la Bataille Flandres, Dunkerque CS 44229, 35042 Rennes Cedex, France
| | - Olivier Rousseaux
- Guerbet group, Centre de Recherche d'Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - Raphaël Tripier
- Univ Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
| | - Maryline Beyler
- Univ Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
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14
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Abad‐Galán L, Cieslik P, Comba P, Gast M, Maury O, Neupert L, Roux A, Wadepohl H. Excited State Properties of Lanthanide(III) Complexes with a Nonadentate Bispidine Ligand. Chemistry 2021; 27:10303-10312. [PMID: 33780569 PMCID: PMC8360039 DOI: 10.1002/chem.202005459] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Indexed: 12/03/2022]
Abstract
EuIII , TbIII , GdIII and YbIII complexes of the nonadentate bispidine derivative L2 (bispidine=3,7-diazabicyclo[3.3.1]nonane) were successfully synthesized and their emission properties studied. The X-ray crystallography reveals full encapsulation by the nonadentate ligand L2 that enforces to all LnIII cations a common highly symmetrical capped square antiprismatic (CSAPR) coordination geometry (pseudo C4v symmetry). The well-resolved identical emission spectra in solid state and in solution confirm equal structures in both media. As therefore expected, this results in long-lived excited states and high emission quantum yields ([EuIII L2 ]+ , H2 O, 298 K, τ=1.51 ms, ϕ=0.35; [TbIII L2 ]+ , H2 O, 298 K, τ=1.95 ms, ϕ=0.68). Together with the very high kinetic and thermodynamic stabilities, these complexes are a possible basis for interesting biological probes.
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Affiliation(s)
- Laura Abad‐Galán
- Université de LyonENS de LyonLaboratoire de ChimieCNRS UMR 5182Université Claude Bernard Lyon 169342LyonFrance
| | - Patrick Cieslik
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
| | - Peter Comba
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
- Universität HeidelbergInterdisciplinary Center for Scientific Computing69120HeidelbergGermany
| | - Michael Gast
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
| | - Olivier Maury
- Université de LyonENS de LyonLaboratoire de ChimieCNRS UMR 5182Université Claude Bernard Lyon 169342LyonFrance
| | - Lucca Neupert
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
| | - Amandine Roux
- Université de LyonENS de LyonLaboratoire de ChimieCNRS UMR 5182Université Claude Bernard Lyon 169342LyonFrance
| | - Hubert Wadepohl
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
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15
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Song B, Wen X, Zhang X, Liu Q, Ma H, Tan M, Yuan J. Bioconjugates of versatile β-diketonate-lanthanide complexes as probes for time-gated luminescence and magnetic resonance imaging of cancer cells in vitro and in vivo. J Mater Chem B 2021; 9:3161-3167. [PMID: 33885620 DOI: 10.1039/d1tb00144b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Magnetic resonance imaging (MRI) and optical imaging (OI) are attractive for constructing bimodal probes due to their complementary imaging characteristics. The combination of these two techniques could be a useful tool to simultaneously obtain both anatomical and molecular information as well as to significantly improve the accuracy of detection. In this study, we found that β-diketonate-lanthanide complexes, BHHBCB-Ln3+, could covalently bind to proteins to exhibit long-lived and intense luminescence (Ln3+ = Eu3+, τ = 0.52 ms, Φ = 0.40) and remarkably high relaxivity (Ln3+ = Gd3+, r1 = 35.67 mM-1 s-1, r2 = 43.25 mM-1 s-1) with excellent water solubility, stability and biocompatibility. Hence, we conjugated BHHBCB-Ln3+ with a tumor-targetable biomacromolecule, transferrin (Tf), to construct the probes, Tf-BHHBCB-Ln3+, for time-gated luminescence (TGL, Ln3+ = Eu3+) and MR (Ln3+ = Gd3+) imaging of cancerous cells in vitro and in vivo. As expected, the as-prepared probes showed high specificity to bind with the transferrin receptor-overexpressed cancerous cells, to enable the probe molecules to be accumulated in these cells. Using Tf-BHHBCB-Ln3+ as probes, the cultured cancerous cells and the tumors in tumor-bearing mice have been clearly visualized by background-free TGL and in vivo MR imaging. The research outcomes suggested the potential of β-diketonate-lanthanide complexes for use in constructing bimodal TGL/MR imaging bioprobes.
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Affiliation(s)
- Bo Song
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China.
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16
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Kostelnik TI, Scheiber H, Cappai R, Choudhary N, Lindheimer F, Guadalupe Jaraquemada-Peláez MD, Orvig C. Phosphonate Chelators for Medicinal Metal Ions. Inorg Chem 2021; 60:5343-5361. [PMID: 33719399 DOI: 10.1021/acs.inorgchem.1c00290] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A family of phosphonate-bearing chelators was synthesized to study their potential in metal-based (radio)pharmaceuticals. Three ligands (H6phospa, H6dipedpa, H6eppy; structures illustrated in manuscript) were fully characterized, including X-ray crystallographic structures of H6phospa and H6dipedpa. NMR spectroscopy techniques were used to confirm the complexation of each ligand with selected trivalent metal ions. These methods were particularly useful in discerning structural information for Sc3+ and La3+ complexes. Solution studies were conducted to evaluate the complex stability of 15 metal complexes. As a general trend, H6phospa was noted to form the most stable complexes, and H6eppy associated with the least stable complexes. Moreover, In3+ complexes were determined to be the most stable, and complexes with La3+ were the least stable, across all metals. Density functional theory (DFT) was employed to calculate structures of H6phospa and H6dipedpa complexes with La3+ and Sc3+. A comparison of experimental 1H NMR spectra with calculated 1H NMR spectra using DFT-optimized structures was used as a method of structure validation. It was noted that theoretical NMR spectra were very sensitive to a number of variables, such as ligand configuration, protonation state, and the number/orientation of explicit water molecules. In general, the inclusion of an explicit second shell of water molecules qualitatively improved the agreement between theoretical and experimental NMR spectra versus a polarizable continuum solvent model alone. Formation constants were also calculated from DFT results using potential-energy optimized structures. Strong dependence of molecular free energies on explicit water molecule number, water molecule configuration, and protonation state was observed, highlighting the need for dynamic data in accurate first-principles calculations of metal-ligand stability constants.
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Affiliation(s)
- Thomas I Kostelnik
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, V6T 1Z1 Vancouver, British Columbia, Canada.,Life Sciences Division, TRIUMF, 4004 Wesbrook Mall, V6T 2A3 Vancouver, British Columbia, Canada
| | - Hayden Scheiber
- Department of Chemistry, University of British Columbia, V6T 1Z1 Vancouver, British Columbia, Canada
| | - Rosita Cappai
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, V6T 1Z1 Vancouver, British Columbia, Canada.,Dipartimento di Scienze della Vita e dell'Ambiente, University of Cagliari, 09042 Cagliari, Italy
| | - Neha Choudhary
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, V6T 1Z1 Vancouver, British Columbia, Canada.,Life Sciences Division, TRIUMF, 4004 Wesbrook Mall, V6T 2A3 Vancouver, British Columbia, Canada
| | - Felix Lindheimer
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, V6T 1Z1 Vancouver, British Columbia, Canada.,Anorganisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 276, 69120 Heidelberg, Germany
| | - María de Guadalupe Jaraquemada-Peláez
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, V6T 1Z1 Vancouver, British Columbia, Canada
| | - Chris Orvig
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, 2036 Main Mall, V6T 1Z1 Vancouver, British Columbia, Canada
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17
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Kovacs D, Kocsi D, Wells JAL, Kiraev SR, Borbas KE. Electron transfer pathways in photoexcited lanthanide(iii) complexes of picolinate ligands. Dalton Trans 2021; 50:4244-4254. [PMID: 33688904 DOI: 10.1039/d1dt00616a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A series of luminescent lanthanide(iii) complexes consisting of 1,4,7-triazacyclononane frameworks and three secondary amide-linked carbostyril antennae were synthesised. The metal binding sites were augmented with two pyridylcarboxylate donors yielding octadentate ligands. The antennae carried methyl, methoxymethyl or trifluoromethyl substituents in their 4-positions, allowing for a range of excited state energies and antenna electronic properties. The 1H NMR spectra of the Eu(iii) complexes were found to be analogous to each other. Similar results were obtained in the solid-state by single-crystal X-ray crystallography, which showed the structures to have nine-coordinate metal ions with heavily distorted tricapped trigonal prismatic geometries. Steady-state and time-resolved luminescence spectroscopy showed that the antennae could sensitize both Tb(iii) and Eu(iii), however, quantum yields were lower than in other octadentate complexes lacking pyridylcarboxylate. Complexes with more electron-poor pyridines were less emissive even when equipped with the same antenna. The oxidation and reduction potentials of the antennae and the pyridinecarboxylates, respectively, were determined by cyclic voltammetry. The obtained values were consistent with electron transfer from the excited antenna to the pyridine providing a previously unexplored quenching pathway that could efficiently compete with energy transfer to the lanthanide. These results show the crucial impact that photophysically innocent ligand binding sites can have on lanthanide luminescence.
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Affiliation(s)
- Daniel Kovacs
- Department of Chemistry, Ångström Laboratory, Box 523, Uppsala University, 75120, Uppsala, Sweden.
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18
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Chirayil S, Jordan VC, Martins AF, Paranawithana N, Ratnakar SJ, Sherry AD. Manganese(II)-Based Responsive Contrast Agent Detects Glucose-Stimulated Zinc Secretion from the Mouse Pancreas and Prostate by MRI. Inorg Chem 2021; 60:2168-2177. [PMID: 33507742 PMCID: PMC8112388 DOI: 10.1021/acs.inorgchem.0c02688] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A Mn(II)-based zinc-sensitive MRI contrast agent, MnPyC3A-BPEN, was prepared, characterized, and applied in imaging experiments to detect glucose-stimulated zinc secretion (GSZS) from the mouse pancreas and prostate in vivo. Thermodynamic and kinetic stability tests showed that MnPyC3A-BPEN has superior kinetic inertness compared to GdDTPA, is less susceptible to transmetalation in the presence of excess Zn2+ ions, and less susceptible to transchelation by albumin. In comparison with other gadolinium-based zinc sensors bearing a single zinc binding moiety, MnPyC3A-BPEN appears to be a reliable alternative for imaging β-cell function in the pancreas and glucose-stimulated zinc secretion from the prostate.
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Affiliation(s)
- Sara Chirayil
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Veronica Clavijo Jordan
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - André F Martins
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
- Werner Siemens Imaging Center, Eberhard Karls University Tübingen, Tübingen 72076, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided and Functionally Instructed Tumor Therapies", University of Tübingen, Tübingen 72076, Germany
- Department of Chemistry, University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Namini Paranawithana
- Department of Chemistry, University of Texas at Dallas, Richardson, Texas 75080, United States
| | - S James Ratnakar
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - A Dean Sherry
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
- Department of Chemistry, University of Texas at Dallas, Richardson, Texas 75080, United States
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19
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Nizou G, Molnár E, Hamon N, Kálmán FK, Fougère O, Rousseaux O, Esteban-Gòmez D, Platas-Iglesias C, Beyler M, Tircsó G, Tripier R. Pyclen-Based Ligands Bearing Pendant Picolinate Arms for Gadolinium Complexation. Inorg Chem 2021; 60:2390-2405. [PMID: 33486958 DOI: 10.1021/acs.inorgchem.0c03277] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We report the synthesis of two pyclen-based regioisomer ligands (pyclen = 3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene) functionalized with picolinic acid pendant arms either at positions 3,9-pc2pa (L5) or 3,6-pc2pa (L6) of the macrocyclic fragment. The ligands were prepared by the regiospecific protection of one of the amine nitrogen atoms of the macrocycle using Boc and Alloc protecting groups, respectively. The X-ray structure of the Gd(III) complex of L5 contains trinuclear [(GdL5)3(H2O)3]3+ entities in which the monomeric units are joined by μ2-η1:η1-carboxylate groups. However, the 1H and 89Y NMR spectra of its Y(III) analogue support the formation of monomeric complexes in solution. The Tb(III) complexes are highly luminescent, with emission quantum yields of up to 28% for [TbL5]+. The luminescence lifetimes recorded in H2O and D2O solutions indicate the presence of a water molecule coordinated to the metal ion, as also evidenced by the 1H relaxivities measured for the Gd(III) analogues. The Gd(III) complexes present very different exchange rates of the coordinated water molecule (kex298 = 87.1 × 106 and 1.06 × 106 s-1 for [GdL5]+ and [GdL6]+, respectively). The very high water exchange rate of [GdL5]+ is associated with the steric hindrance originating from the coordination of the ligand around the water binding site, which favors a dissociatively activated water exchange process. The Gd(III) complexes present rather high thermodynamic stabilities (log KGdL = 20.47 and 19.77 for [GdL5]+ and [GdL6]+, respectively). Furthermore, these complexes are remarkably inert with respect to their acid-assisted dissociation, in particular the complex of L5.
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Affiliation(s)
- Gwladys Nizou
- Univ. Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
| | - Enikő Molnár
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | - Nadège Hamon
- Univ. Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
| | - Ferenc Krisztián Kálmán
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | - Olivier Fougère
- Groupe Guerbet, Centre de Recherche d'Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - Olivier Rousseaux
- Groupe Guerbet, Centre de Recherche d'Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - David Esteban-Gòmez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Maryline Beyler
- Univ. Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
| | - Gyula Tircsó
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | - Raphaël Tripier
- Univ. Brest, UMR-CNRS 6521 CEMCA, 6 avenue Victor le Gorgeu, 29238 Brest, France
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20
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Aquino LEDN, Barbosa GA, Ramos JDL, O K Giese S, Santana FS, Hughes DL, Nunes GG, Fu L, Fang M, Poneti G, Carneiro Neto AN, Moura RT, Ferreira RAS, Carlos LD, Macedo AG, Soares JF. Seven-Coordinate Tb 3+ Complexes with 90% Quantum Yields: High-Performance Examples of Combined Singlet- and Triplet-to-Tb 3+ Energy-Transfer Pathways. Inorg Chem 2021; 60:892-907. [PMID: 33393287 DOI: 10.1021/acs.inorgchem.0c03020] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Seven-coordinate, pentagonal-bipyramidal (PBP) complexes [Ln(bbpen)Cl] and [Ln(bbppn)Cl], in which Ln = Tb3+ (products I and II), Eu3+ (III and IV), and Gd3+ (V and VI), with bbpen2- = N,N'-bis(2-oxidobenzyl)-N,N'-bis(pyridin-2-ylmethyl)ethylenediamine and bbppn2- = N,N'-bis(2-oxidobenzyl)-N,N'-bis(pyridin-2-ylmethyl)-1,2-propanediamine, were synthesized and characterized by single-crystal X-ray diffraction analysis, alternating-current magnetic susceptibility measurements, and photoluminescence (steady-state and time-resolved) spectroscopy. Under a static magnetic field of 0.1 T, the Tb3+ complexes I and II revealed single-ion-magnet behavior. Also, upon excitation at 320 nm at 300 K, I and II presented very high absolute emission quantum yields (0.90 ± 0.09 and 0.92 ± 0.09, respectively), while the corresponding Eu3+ complexes III and IV showed no photoluminescence. Detailed theoretical calculations on the intramolecular energy-transfer rates for the Tb3+ products indicated that both singlet and triplet ligand excited states contribute efficiently to the overall emission performance. The expressive quantum yields, QLnL, measured for I and II in the solid state and a dichloromethane solution depend on the excitation wavelength, being higher at 320 nm. Such a dependence was rationalized by computing the intersystem crossing rates (WISC) and singlet fluorescence lifetimes (τS) related to the population dynamics of the S1 and T1 levels. Thin films of product II showed high air stability and photostability upon continuous UV illumination, which allowed their use as downshifting layers in a green light-emitting device (LED). The prototypes presented a luminous efficacy comparable with those found in commercial LED coatings, without requiring encapsulation or dispersion of II in host matrixes. The results indicate that the PBP environment determined by the ethylenediamine (en)-based ligands investigated in this work favors the outstanding optical properties in Tb3+ complexes. This work presents a comprehensive structural, chemical, and spectroscopic characterization of two Tb3+ complexes of mixed-donor, en-based ligands, focusing on their outstanding optical properties. They constitute good molecular examples in which both triplet and singlet excited states provide energy to the Tb3+ ion and lead to high values of QLnL.
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Affiliation(s)
| | - Guilherme A Barbosa
- Department of Chemistry, Federal University of Paraná, 81530-900 - Curitiba-PR, Brazil
| | - Jaqueline de L Ramos
- Department of Chemistry, Federal University of Paraná, 81530-900 - Curitiba-PR, Brazil
| | - Siddhartha O K Giese
- Department of Chemistry, Federal University of Paraná, 81530-900 - Curitiba-PR, Brazil
| | - Francielli S Santana
- Department of Chemistry, Federal University of Paraná, 81530-900 - Curitiba-PR, Brazil
| | - David L Hughes
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, U.K
| | - Giovana G Nunes
- Department of Chemistry, Federal University of Paraná, 81530-900 - Curitiba-PR, Brazil
| | - Lianshe Fu
- Phantom-g, CICECO - Aveiro Institute of Materials, Department of Physics, University of Aveiro, 3810-193 - Aveiro, Portugal
| | - Ming Fang
- Phantom-g, CICECO - Aveiro Institute of Materials, Department of Physics, University of Aveiro, 3810-193 - Aveiro, Portugal
| | - Giordano Poneti
- Institute of Chemistry, Federal University of Rio de Janeiro, 21941-909 - Rio de Janeiro-RJ, Brazil
| | - Albano N Carneiro Neto
- Phantom-g, CICECO - Aveiro Institute of Materials, Department of Physics, University of Aveiro, 3810-193 - Aveiro, Portugal
| | - Renaldo T Moura
- Department of Chemistry and Physics, Federal University of Paraíba, 58397-000 - Areia-PB, Brazil
| | - Rute A S Ferreira
- Phantom-g, CICECO - Aveiro Institute of Materials, Department of Physics, University of Aveiro, 3810-193 - Aveiro, Portugal
| | - Luís D Carlos
- Phantom-g, CICECO - Aveiro Institute of Materials, Department of Physics, University of Aveiro, 3810-193 - Aveiro, Portugal
| | - Andreia G Macedo
- Phantom-g, CICECO - Aveiro Institute of Materials, Department of Physics, University of Aveiro, 3810-193 - Aveiro, Portugal.,Department of Physics, Federal University of Technology, 80230-901 - Curitiba, PR, Brazil
| | - Jaísa F Soares
- Department of Chemistry, Federal University of Paraná, 81530-900 - Curitiba-PR, Brazil
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21
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Abad Galán L, Hamon N, Nguyen C, Molnár E, Kiss J, Mendy J, Hadj-Kaddour K, Onofre M, Trencsényi G, Monnereau C, Beyler M, Tircsó G, Gary-Bobo M, Maury O, Tripier R. Design of polyazamacrocyclic Gd3+ theranostic agents combining magnetic resonance imaging and two-photon photodynamic therapy. Inorg Chem Front 2021. [DOI: 10.1039/d0qi01519a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
New “all-in-one” theranostic systems, combining a magnetic resonance imaging contrast agent with a biphotonic photodynamic therapy photosensitiser generating cytotoxic singlet oxygen, were successfully developed and characterized.
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22
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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: 29] [Impact Index Per Article: 7.3] [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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23
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Fremy G, Raibaut L, Cepeda C, Sanson M, Boujut M, Sénèque O. A novel DOTA-like building block with a picolinate arm for the synthesis of lanthanide complex-peptide conjugates with improved luminescence properties. J Inorg Biochem 2020; 213:111257. [DOI: 10.1016/j.jinorgbio.2020.111257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/07/2020] [Accepted: 09/09/2020] [Indexed: 12/28/2022]
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24
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Nizou G, Favaretto C, Borgna F, Grundler PV, Saffon-Merceron N, Platas-Iglesias C, Fougère O, Rousseaux O, van der Meulen NP, Müller C, Beyler M, Tripier R. Expanding the Scope of Pyclen-Picolinate Lanthanide Chelates to Potential Theranostic Applications. Inorg Chem 2020; 59:11736-11748. [DOI: 10.1021/acs.inorgchem.0c01664] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Gwladys Nizou
- Univ. Brest, UMR CNRS 6521 CEMCA, 6 avenue Le Gorgeu, CS93837, 29200 Brest, France
| | - Chiara Favaretto
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, Forschungsstrasse 111, 5232 Villigen-PSI, Switzerland
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Francesca Borgna
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, Forschungsstrasse 111, 5232 Villigen-PSI, Switzerland
| | - Pascal V. Grundler
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, Forschungsstrasse 111, 5232 Villigen-PSI, Switzerland
| | - Nathalie Saffon-Merceron
- Service commun Rayons X ICT-FR2599, Université Paul Sabatier, Bâtiment 2R1, 118 route de Narbonne, 31062 Toulouse, Cedex 09, France
| | - Carlos Platas-Iglesias
- Departamento de Química, Facultade de Ciencias & Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain
| | - Olivier Fougère
- Guerbet group, Centre de Recherche d’Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG, Cedex, France
| | - Olivier Rousseaux
- Guerbet group, Centre de Recherche d’Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG, Cedex, France
| | - Nicholas P. van der Meulen
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, Forschungsstrasse 111, 5232 Villigen-PSI, Switzerland
- Laboratory of Radiochemistry, Paul Scherrer Institute, Forschungsstrasse 111, 5232 Villigen-PSI, Switzerland
| | - Cristina Müller
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, Forschungsstrasse 111, 5232 Villigen-PSI, Switzerland
- Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland
| | - Maryline Beyler
- Univ. Brest, UMR CNRS 6521 CEMCA, 6 avenue Le Gorgeu, CS93837, 29200 Brest, France
| | - Raphaël Tripier
- Univ. Brest, UMR CNRS 6521 CEMCA, 6 avenue Le Gorgeu, CS93837, 29200 Brest, France
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25
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McCarver GA, Hinde RJ, Vogiatzis KD. Selecting Quantum-Chemical Methods for Lanthanide-Containing Molecules: A Balance between Accuracy and Efficiency. Inorg Chem 2020; 59:10492-10500. [DOI: 10.1021/acs.inorgchem.0c00808] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Gavin A. McCarver
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, United States
| | - Robert J. Hinde
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, United States
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26
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Hamon N, Roux A, Beyler M, Mulatier JC, Andraud C, Nguyen C, Maynadier M, Bettache N, Duperray A, Grichine A, Brasselet S, Gary-Bobo M, Maury O, Tripier R. Pyclen-Based Ln(III) Complexes as Highly Luminescent Bioprobes for In Vitro and In Vivo One- and Two-Photon Bioimaging Applications. J Am Chem Soc 2020; 142:10184-10197. [PMID: 32368907 DOI: 10.1021/jacs.0c03496] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In addition to the already described ligand L4a, two pyclen-based lanthanide chelators, L4b and L4c, bearing two specific picolinate two-photon antennas (tailor-made for each targeted metal) and one acetate arm arranged in a dissymmetrical manner, have been synthesized, to form a complete family of lanthanide luminescent bioprobes: [EuL4a], [SmL4a], [YbL4b], [TbL4c], and [DyL4c]. Additionally, the symmetrically arranged regioisomer L4a' was also synthesized as well as its [EuL4a'] complex to highlight the astonishing positive impact of the dissymmetrical N-distribution of the functional chelating arms. The investigation clearly shows the high performance of each bioprobe, which, depending on the complexed lanthanide, could be used in various applications. Each presents high brightness, quantum yields, and lifetimes. Staining of the complexes into living human breast cancer cells was observed. In addition, in vivo two-photon microscopy was performed for the first time on a living zebrafish model with [EuL4a]. No apparent toxicity was detected on the growth of the zebrafish, and images of high quality were obtained.
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Affiliation(s)
- Nadège Hamon
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor le Gorgeu, 29200 Brest, France
| | - Amandine Roux
- Univ Lyon ENS de Lyon, CNRS Laboratoire de Chimie UMR 5182, Université Claude Bernard Lyon 1, F-69342 Lyon, France
| | - Maryline Beyler
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor le Gorgeu, 29200 Brest, France
| | - Jean-Christophe Mulatier
- Univ Lyon ENS de Lyon, CNRS Laboratoire de Chimie UMR 5182, Université Claude Bernard Lyon 1, F-69342 Lyon, France
| | - Chantal Andraud
- Univ Lyon ENS de Lyon, CNRS Laboratoire de Chimie UMR 5182, Université Claude Bernard Lyon 1, F-69342 Lyon, France
| | | | - Marie Maynadier
- NanoMedSyn, 15 Avenue Charles Flahault, F-34093 Montpellier Cedex 05, France
| | - Nadir Bettache
- IBMM, Univ Montpellier, CNRS, ENSCM, F-34000 Montpellier, France
| | - Alain Duperray
- INSERM, U1209, Université Grenoble 896 Alpes, IAB, F-38000 Grenoble, France
| | - Alexei Grichine
- INSERM, U1209, Université Grenoble 896 Alpes, IAB, F-38000 Grenoble, France
| | - Sophie Brasselet
- Univ Aix Marseille, CNRS, Centrale Marseille, Institut Fresnel, UMR 7249, F-13013 Marseille, France
| | - Magali Gary-Bobo
- IBMM, Univ Montpellier, CNRS, ENSCM, F-34000 Montpellier, France
| | - Olivier Maury
- Univ Lyon ENS de Lyon, CNRS Laboratoire de Chimie UMR 5182, Université Claude Bernard Lyon 1, F-69342 Lyon, France
| | - Raphaël Tripier
- Univ Brest, UMR CNRS 6521 CEMCA, 6 Avenue Victor le Gorgeu, 29200 Brest, France
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27
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Frías JC, Soriano J, Blasco S, García-España E, Rodríguez-Rodríguez A, Esteban-Gómez D, Carniato F, Botta M, Platas-Iglesias C, Albelda MT. Macrocyclic Pyclen-Based Gd 3+ Complex with High Relaxivity and pH Response. Inorg Chem 2020; 59:7306-7317. [PMID: 32379437 DOI: 10.1021/acs.inorgchem.0c00690] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report the synthesis and characterization of the macrocyclic ligand 2,2'-((2-(3,9-bis(carboxymethyl)-3,6,9-triaza-1(2,6)-pyridinacyclodecaphane-6-yl)ethyl)azanediyl)diacetic acid (H4L) and several of its complexes with lanthanide ions. The structure of the free ligand was determined using X-ray diffraction measurements. Two N atoms of the pyclen moiety in the trans position are protonated in the solid state, together with the exocyclic N atom and one of the carboxylate groups of the ligand. The relaxivity of the Gd3+ complex was found to increase from 6.7 mM-1 s-1 at pH 8.6 to 8.5 mM-1 s-1 below pH ≈ 6.0. Luminescence lifetime measurements recorded from H2O and D2O solutions of the Eu3+ complex evidence the presence of a single complex species in solution at low pH (∼5.0) that contains two inner-sphere water molecules. DFT calculations suggest that the coordination environment of the Ln3+ ion is fulfilled by the four N atoms of the pyclen unit, two oxygen atoms of the macrocyclic acetate groups, and an oxygen atom of an exocyclic carboxylate group. The two inner-sphere water molecules complete coordination number nine around the metal ion. At high pH (∼9.3), the lifetime of the excited 5D0 level of Eu3+ displays a biexponential behavior that can be attributed to the presence of two species in solution with hydration numbers of q = 0 and q = 1. The 1H NMR and DOSY spectra recorded from solutions of the Eu3+ and Y3+ complexes reveal a structural change triggered by pH and the formation of small aggregates at high pH values.
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Affiliation(s)
- Juan C Frías
- Departamento de Ciencias Biomédicas, Universidad CEU-Cardenal Herrera, CEU Universities, C/Ramón y Cajal, s/n, 46115 Alfara del Patriarca, Valencia, Spain
| | - José Soriano
- Departamento de Quı́mica Inorgánica, Instituto de Ciencia Molecular, Universidad de Valencia, Edificio de Institutos de Paterna, Apdo 22085, 46071 Valencia, Spain
| | - Salvador Blasco
- Departamento de Quı́mica Inorgánica, Instituto de Ciencia Molecular, Universidad de Valencia, Edificio de Institutos de Paterna, Apdo 22085, 46071 Valencia, Spain
| | - Enrique García-España
- Departamento de Quı́mica Inorgánica, Instituto de Ciencia Molecular, Universidad de Valencia, Edificio de Institutos de Paterna, Apdo 22085, 46071 Valencia, Spain
| | - Aurora Rodríguez-Rodríguez
- Centro de Investigacións Cientı́ficas Avanzadas (CICA) and Departamento de Quı́mica, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - David Esteban-Gómez
- Centro de Investigacións Cientı́ficas Avanzadas (CICA) and Departamento de Quı́mica, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Fabio Carniato
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale "A. Avogadro", Viale T. Michel 11, 15121 Alessandria, Italy
| | - Mauro Botta
- 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 Cientı́ficas Avanzadas (CICA) and Departamento de Quı́mica, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - M Teresa Albelda
- Departamento de Quı́mica Inorgánica, Universidad de Valencia, C/Dr. Moliner 50, 46100 Burjasot, Valencia, Spain
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28
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Monteiro JHSK. Recent Advances in Luminescence Imaging of Biological Systems Using Lanthanide(III) Luminescent Complexes. Molecules 2020; 25:E2089. [PMID: 32365719 PMCID: PMC7248892 DOI: 10.3390/molecules25092089] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 04/25/2020] [Accepted: 04/27/2020] [Indexed: 12/15/2022] Open
Abstract
The use of luminescence in biological systems allows one to diagnose diseases and understand cellular processes. Molecular systems, particularly lanthanide(III) complexes, have emerged as an attractive system for application in cellular luminescence imaging due to their long emission lifetimes, high brightness, possibility of controlling the spectroscopic properties at the molecular level, and tailoring of the ligand structure that adds sensing and therapeutic capabilities. This review aims to provide a background in luminescence imaging and lanthanide spectroscopy and discuss selected examples from the recent literature on lanthanide(III) luminescent complexes in cellular luminescence imaging, published in the period 2016-2020. Finally, the challenges and future directions that are pointing for the development of compounds that are capable of executing multiple functions and the use of light in regions where tissues and cells have low absorption will be discussed.
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29
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Leygue N, Galaup C, Lopera A, Delgado-Pinar E, Williams RM, Gornitzka H, Zwier JM, García-España E, Lamarque L, Picard C. Tripyridinophane Platform Containing Three Acetate Pendant Arms: An Attractive Structural Entry for the Development of Neutral Eu(III) and Tb(III) Complexes in Aqueous Solution. Inorg Chem 2020; 59:1496-1512. [PMID: 31913029 DOI: 10.1021/acs.inorgchem.9b03345] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report a detailed characterization of Eu3+ and Tb3+ complexes derived from a tripyridinophane macrocycle bearing three acetate side arms (H3tpptac). Tpptac3- displays an overall basicity (∑ log KiH) of 24.5, provides the formation of mononuclear ML species, and shows a good binding affinity for Ln3+ (log KLnL = 17.5-18.7). These complexes are also thermodynamically stable at physiological pH (pEu = 18.6, pTb = 18.0). It should be noted that the pGd value of Gd-tpptac (18.4) is only slightly lower than that of commercially available MRI contrast agents such as Gd-dota (pGd = 19.2). Moreover, a very good selectivity for these ions over the endogenous cations (log KCuL = 14.4, log KZnL = 12.9, and log KCaL = 9.3) is observed. The X-ray structure of the terbium complex shows the metal coordinated by the nine N6O3 donor set of the ligand and one inner-sphere water molecule. DFT calculations result in two Eu-tpptac structures with similar bond energies (ΔE = 0.145 eV): one structure in which the water is coordinated to the metal ion and one structure in which the water molecule is farther away from the ion, bound to the ligand with an OH-π bond. By detailed luminescence experiments, we demonstrate that the europium complex in aqueous solution presents a hydration equilibrium between nine-coordinate, dehydrated [Eu-tpptac]0 and ten-coordinate, monohydrated [Eu-tpptac(H2O)]0 species. A similar trend is observed for the terbium complex. Despite the presence of this hydration equilibrium, the H3tpptac ligand sensitizes Eu3+ and Tb3+ luminescence efficiently in buffered water at physiological pH. Particularly, the terbium complex displays a long excited-state lifetime of 2.24 ms and an overall quantum yield of 33% with a brightness of 3600 M-1 cm-1. Such features of Ln3+ complexes of H3tpptac indicate that this platform appears to be particularly appealing for the further development of luminescent lanthanide labels.
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Affiliation(s)
- Nadine Leygue
- Laboratoire de Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique (SPCMIB) , Université Paul Sabatier-Toulouse III/CNRS (UMR5068) , 118 route de Narbonne , F-31062 Toulouse , France
| | - Chantal Galaup
- Laboratoire de Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique (SPCMIB) , Université Paul Sabatier-Toulouse III/CNRS (UMR5068) , 118 route de Narbonne , F-31062 Toulouse , France
| | - Alberto Lopera
- Instituto de Ciencia Molecular (ICMOL) , Universitat de València , C/Catedrático José Beltrán 2 , 46980 Paterna , Spain
| | - Estefanía Delgado-Pinar
- Instituto de Ciencia Molecular (ICMOL) , Universitat de València , C/Catedrático José Beltrán 2 , 46980 Paterna , Spain
| | - René M Williams
- Molecular Photonics Group, Van 't Hoff Institute for Molecular Sciences , University of Amsterdam , P.O. Box 94157, 1090 GD Amsterdam , The Netherlands
| | - Heinz Gornitzka
- CNRS, LCC , Université de Toulouse, UPS, INPT , 205 Route de Narbonne , F-31077 Toulouse Cedex 4 , France
| | - Jurriaan M Zwier
- Cisbio bioassays , Parc Marcel Boiteux, BP 84175, 30200 Codolet , France
| | - Enrique García-España
- Instituto de Ciencia Molecular (ICMOL) , Universitat de València , C/Catedrático José Beltrán 2 , 46980 Paterna , Spain
| | - Laurent Lamarque
- Cisbio bioassays , Parc Marcel Boiteux, BP 84175, 30200 Codolet , France
| | - Claude Picard
- Laboratoire de Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique (SPCMIB) , Université Paul Sabatier-Toulouse III/CNRS (UMR5068) , 118 route de Narbonne , F-31062 Toulouse , France
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30
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Johnston HM, Pota K, Barnett MM, Kinsinger O, Braden P, Schwartz TM, Hoffer E, Sadagopan N, Nguyen N, Yu Y, Gonzalez P, Tircsó G, Wu H, Akkaraju G, Chumley MJ, Green KN. Enhancement of the Antioxidant Activity and Neurotherapeutic Features through Pyridol Addition to Tetraazamacrocyclic Molecules. Inorg Chem 2019; 58:16771-16784. [PMID: 31774280 PMCID: PMC7323501 DOI: 10.1021/acs.inorgchem.9b02932] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alzheimer's and other neurodegenerative diseases are chronic conditions affecting millions of individuals worldwide. Oxidative stress is a consistent component described in the development of many neurodegenerative diseases. Therefore, innovative strategies to develop drug candidates that overcome oxidative stress in the brain are needed. To target these challenges, a new, water-soluble 12-membered tetraaza macrocyclic pyridinophane L4 was designed and produced using a building-block approach. Potentiometric data show that the neutral species of L4 provides interesting zwitterionic behavior at physiological pH, akin to amino acids, and a nearly ideal isoelectric point of 7.3. The copper(II) complex of L4 was evaluated by X-ray diffraction and cyclic voltammetry to show the potential modes of antioxidant activity derived, which was also demonstrated by 2,2-diphenyl-1-picrylhydrazyl and coumarin carboxylic acid antioxidant assays. L4 was shown to have dramatically enhanced antioxidant activity and increased biological compatibility compared to parent molecules reported previously. L4 attenuated hydrogen peroxide (H2O2)-induced cell viability loss more efficiently than precursor molecules in the mouse hippocampal HT-22 cell model. L4 also showed potent (fM) level protection against H2O2 cell death in a BV2 microglial cell culture. Western blot studies indicated that L4 enhanced the cellular antioxidant defense capacity via Nrf2 signaling activation as well. Moreover, a low-cost analysis and high metabolic stability in phase I and II models were observed. These encouraging results show how the rational design of lead compounds is a suitable strategy for the development of treatments for neurodegenerative diseases where oxidative stress plays a substantial role.
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Affiliation(s)
- Hannah M. Johnston
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Kristof Pota
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Madalyn M. Barnett
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Olivia Kinsinger
- Department of Biology, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Paige Braden
- Department of Biology, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Timothy M. Schwartz
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Emily Hoffer
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Nishanth Sadagopan
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Nam Nguyen
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Yu Yu
- Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas (UNT) Health Science Center, Fort Worth, Texas 76107, United States
| | - Paulina Gonzalez
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Gyula Tircsó
- Department of Inorganic and Analytical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, Debrecen H-4010, Hungary
| | - Hongli Wu
- Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas (UNT) Health Science Center, Fort Worth, Texas 76107, United States
- North Texas Eye Research Institute, University of North Texas (UNT) Health Science Center, Fort Worth, Texas 76107, United States
| | - Giridhar Akkaraju
- Department of Biology, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Michael J. Chumley
- Department of Biology, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
| | - Kayla N. Green
- Department of Chemistry and Biochemistry, Texas Christian University (TCU), 2950 S. Bowie, Fort Worth, Texas 76129, United States
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31
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Baranyai Z, Tircsó G, Rösch F. The Use of the Macrocyclic Chelator DOTA in Radiochemical Separations. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900706] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Zsolt Baranyai
- Bracco Research Centre Bracco Imaging spa Via Ribes 5 10010 Colleretto Giacosa (TO) Italy
| | - Gyula Tircsó
- Department of Physical Chemistry Faculty of Science and Technology University of Debrecen Egyetem tér 1 Debrecen 4032 Hungary
| | - Frank Rösch
- Institute of Nuclear Chemistry Johannes Gutenberg‐University of Mainz Fritz‐Strassmann‐Weg 2 55128 Mainz Germany
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32
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Green KN, Pota K, Tircsó G, Gogolák RA, Kinsinger O, Davda C, Blain K, Brewer SM, Gonzalez P, Johnston HM, Akkaraju G. Dialing in on pharmacological features for a therapeutic antioxidant small molecule. Dalton Trans 2019; 48:12430-12439. [PMID: 31342985 PMCID: PMC6863055 DOI: 10.1039/c9dt01800j] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The pyridinophane molecule L2 (3,6,9,15-tetraazabicyclo[9.3.1]penta-deca-1(15),11,13-trien-13-ol) has shown promise as a therapuetic for neurodegenerative diseases involving oxidative stress and metal ion misregulation. Protonation and metal binding stability constants with Mg2+, Ca2+, Cu2+, and Zn2+ ions were determined to further explore the therapeutic and pharmacological potential of this water soluble small molecule. These studies show that incorporation of an -OH group in position 4 of the pyridine ring decreases the pI values compared to cyclen and L1 (3,6,9,15-tetraazabicyclo[9.3.1]penta-deca-1(15),11,13-triene). Furthermore, this approach tunes the basicity of the tetra-aza macrocyclic ligand through the enhanced resonance stabilization of the -OH in position 4 and rigidity of the pyridine ring such that L2 has increased basicity compared to previously reported tetra-aza macrocycles. A metal binding preference for Cu2+, a redox cycling agent known to produce oxidative stress, indicates that this would be the in vivo metal target of L2. However, the binding constant of L2 with Cu2+ is moderated compared to cyclen due to the rigidity of the ligand and shows how ligand design can be used to tune metal selectivity. An IC50 = 298.0 μM in HT-22 neuronal cells was observed. Low metabolic liability was determined in both Phase I and II in vitro models. Throughout these studies other metal binding systems were used for comparison and as appropriate controls. The reactivity reported to date and pharmacological features described herein warrant further studies in vivo and the pursuit of L2 congeners using the knowledge that pyridine substitution in a pyridinophane can be used to tune the structure of the ligand and retain the positive therapeutic outcomes.
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Affiliation(s)
- Kayla N Green
- Department of Chemistry and Biochemistry, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA.
| | - Kristof Pota
- Department of Chemistry and Biochemistry, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA.
| | - Gyula Tircsó
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, Debrecen, H-4010, Hungary
| | - Réka Anna Gogolák
- Department of Physical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, Debrecen, H-4010, Hungary
| | - Olivia Kinsinger
- Department of Biology, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA
| | - Collin Davda
- Department of Chemistry and Biochemistry, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA.
| | - Kimberly Blain
- Department of Chemistry and Biochemistry, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA. and Department of Biology, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA
| | - Samantha M Brewer
- Department of Chemistry and Biochemistry, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA.
| | - Paulina Gonzalez
- Department of Chemistry and Biochemistry, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA.
| | - Hannah M Johnston
- Department of Chemistry and Biochemistry, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA.
| | - Giridhar Akkaraju
- Department of Biology, Texas Christian University, 2950 S. Bowie, Fort Worth, TX 76129, USA
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Clough TJ, Jiang L, Wong KL, Long NJ. Ligand design strategies to increase stability of gadolinium-based magnetic resonance imaging contrast agents. Nat Commun 2019; 10:1420. [PMID: 30926784 PMCID: PMC6441101 DOI: 10.1038/s41467-019-09342-3] [Citation(s) in RCA: 167] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 12/20/2018] [Indexed: 01/08/2023] Open
Abstract
Gadolinium(III) complexes have been widely utilised as magnetic resonance imaging (MRI) contrast agents for decades. In recent years however, concerns have developed about their toxicity, believed to derive from demetallation of the complexes in vivo, and the relatively large quantities of compound required for a successful scan. Recent efforts have sought to enhance the relaxivity of trivalent gadolinium complexes without sacrificing their stability. This review aims to examine the strategic design of ligands synthesised for this purpose, provide an overview of recent successes in gadolinium-based contrast agent development and assess the requirements for clinical translation.
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Affiliation(s)
- Thomas J Clough
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, Wood Lane, London, W12 0BZ, UK
| | - Lijun Jiang
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, Wood Lane, London, W12 0BZ, UK
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China
| | - Ka-Leung Wong
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China.
| | - Nicholas J Long
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, White City Campus, Wood Lane, London, W12 0BZ, UK.
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