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Evtushenko A, Evtushenko V, Gusakova A, Suslova T, Varlamova Y, Zavadovskiy K, Lebedev D, Kutikhin A, Pavlyukova E, Mamchur S. Neurohumoral Markers of Cardiac Autonomic Denervation after Surgical Ablation of Long-Standing Persistent Atrial Fibrillation. Life (Basel) 2023; 13:1340. [PMID: 37374123 PMCID: PMC10300786 DOI: 10.3390/life13061340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 06/02/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
Although the autonomic nervous system has an evident impact on cardiac electrophysiology and radiofrequency ablation (RFA) is the conventional technique for treating persistent atrial fibrillation, the specific effects of RFA have been insufficiently studied to date. Here, we investigated whether RFA affects neurohumoral transmitter levels and myocardial 123I-metaiodobenzylguanidine (123I-MIBG) uptake. To perform this task, we compared two groups of patients with acquired valvular heart disease: patients who had undergone surgical AF ablation and patients with sinus rhythm. The decrease in norepinephrine (NE) level in the coronary sinus had a direct association with the heart-to-mediastinum ratio (p = 0.02) and a negative correlation with 123I-MIBG uptake defects (p = 0.01). The NE level decreased significantly after the main surgery, both in patients with AF (p = 0.0098) and sinus rhythm (p = 0.0039). Furthermore, the intraoperative difference between the norepinephrine levels in the ascending aorta and coronary sinus (ΔNE) of -400 pg/mL was determined as a cut-off value to evaluate RFA efficacy, as denervation failed in all patients with ΔNE < -400 pg/mL. Hence, ΔNE can be utilized to predict the efficacy of the "MAZE-IV" procedure and to assess the risk of AF recurrence after RFA.
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Affiliation(s)
- Alexey Evtushenko
- Department of Cardiovascular Surgery, Research Institute for Complex Issues of Cardiovascular Diseases, 6 Sosnovy Boulevard, Kemerovo 650002, Russia; (A.E.); (S.M.)
| | - Vladimir Evtushenko
- Cardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, 111a Kievskaya Street, Tomsk 634012, Russia
| | - Anna Gusakova
- Cardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, 111a Kievskaya Street, Tomsk 634012, Russia
| | - Tatiana Suslova
- Cardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, 111a Kievskaya Street, Tomsk 634012, Russia
| | - Yulia Varlamova
- Cardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, 111a Kievskaya Street, Tomsk 634012, Russia
| | - Konstantin Zavadovskiy
- Cardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, 111a Kievskaya Street, Tomsk 634012, Russia
| | - Denis Lebedev
- Department of Cardiovascular Surgery, Research Institute for Complex Issues of Cardiovascular Diseases, 6 Sosnovy Boulevard, Kemerovo 650002, Russia; (A.E.); (S.M.)
| | - Anton Kutikhin
- Department of Cardiovascular Surgery, Research Institute for Complex Issues of Cardiovascular Diseases, 6 Sosnovy Boulevard, Kemerovo 650002, Russia; (A.E.); (S.M.)
| | - Elena Pavlyukova
- Cardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, 111a Kievskaya Street, Tomsk 634012, Russia
| | - Sergey Mamchur
- Department of Cardiovascular Surgery, Research Institute for Complex Issues of Cardiovascular Diseases, 6 Sosnovy Boulevard, Kemerovo 650002, Russia; (A.E.); (S.M.)
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2
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Hong D, Lee K. Polymorphic structures of 3-phenyl-1 H-1,3-benzo-diazol-2(3 H)-one. Acta Crystallogr E Crystallogr Commun 2023; 79:534-537. [PMID: 37288468 PMCID: PMC10242737 DOI: 10.1107/s2056989023003961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 05/03/2023] [Indexed: 06/09/2023]
Abstract
The polymorphic structures (I and II) of 3-phenyl-1H-1,3-benzo-diazol-2(3H)-one, C13H10N2O, acquired from pentane diffusion into the solution in THF, are reported. The structures show negligible differences in bond distances and angles, but the C-N-C-C torsion angles between the backbone and the phenyl substituent, 123.02 (15)° for I and 137.18 (11)° for II, are different. Compound I features a stronger C=O⋯H-N hydrogen bond than that in II, while the structure of II exhibits a stronger π-π inter-action than in I, as confirmed by the shorter inter-centroid distance [3.3257 (8) Å in II in comparison to 3.6862 (7) Å in I]. Overall, the supra-molecular inter-actions of I and II are distinct, presumably originating from the variation in the dihedral angle.
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Affiliation(s)
- Dabeen Hong
- Department of Chemical Education and Research Institute of Natural Sciences, Gyeongsang National University, Gyeongsangnam-do 52828, Republic of Korea
| | - Kyounghoon Lee
- Department of Chemical Education and Research Institute of Natural Sciences, Gyeongsang National University, Gyeongsangnam-do 52828, Republic of Korea
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3
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Taddei C, Gee AD. Recent progress in [ 11 C]carbon dioxide ([ 11 C]CO 2 ) and [ 11 C]carbon monoxide ([ 11 C]CO) chemistry. J Labelled Comp Radiopharm 2018; 61:237-251. [PMID: 29274276 PMCID: PMC6485328 DOI: 10.1002/jlcr.3596] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 11/20/2017] [Accepted: 12/12/2017] [Indexed: 01/07/2023]
Abstract
[11 C]Carbon dioxide ([11 C]CO2 ) and [11 C]carbon monoxide ([11 C]CO) are 2 attractive precursors for labelling the carbonyl position (C═O) in a vast range of functionalised molecules (eg, ureas, amides, and carboxylic acids). The development of radiosynthetic methods to produce functionalised 11 C-labelled compounds is required to enhance the radiotracers available for positron emission tomography, molecular, and medical imaging applications. Following a brief summary of secondary 11 C-precursor production and uses, the review focuses on recent progress with direct 11 C-carboxylation routes with [11 C]CO2 and 11 C-carbonylation with [11 C]CO. Novel approaches to generate [11 C]CO using CO-releasing molecules (CO-RMs), such as silacarboxylic acids and disilanes, applied to radiochemistry are described and compared with standard [11 C]CO production methods. These innovative [11 C]CO synthesis strategies represent efficient and reliable [11 C]CO production processes, enabling the widespread use of [11 C]CO chemistry within the wider radiochemistry community.
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Affiliation(s)
- Carlotta Taddei
- School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
| | - Antony D. Gee
- School of Biomedical Engineering and Imaging SciencesKing's College LondonLondonUK
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4
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Meng Y, Wang B, Ren L, Zhao Q, Yu W, Chang J. I2-Mediated transition-metal-free aromatic C–H amination for the synthesis of benzimidazol-2-ones and related heterocycles. NEW J CHEM 2018. [DOI: 10.1039/c8nj03166e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A practical I2-mediated aromatic C–H amination reaction was established for benzimidazol-2-one synthesis under transition-metal-free conditions. The present reaction can be performed directly from disubstituted amines and isocyanates without the purification of the urea intermediates in a scalable fashion.
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Affiliation(s)
- Yinggao Meng
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- China
| | - Bingnan Wang
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- China
| | - Linning Ren
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- China
| | - Qiongli Zhao
- Collaborative Innovation Centre of New Drug Research and Safety Evaluation
- China
- School of Pharmaceutical Sciences
- Zhengzhou University
- Zhengzhou
| | - Wenquan Yu
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- China
| | - Junbiao Chang
- College of Chemistry and Molecular Engineering
- Zhengzhou University
- Zhengzhou
- China
- Collaborative Innovation Centre of New Drug Research and Safety Evaluation
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5
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Lu Y, Jung JH, Lee HJ, Moon BS, Lee BC, Kim SE. Synthesis andIn VivoEvaluation of a Kit-Type99mTc-labeledN-(2-Aminoethyl)-3-(4-(2-hydroxy-3-(isopropylaminopropoxy)phenyl)propanamide as a Selective β1-Adrenoceptor-binding SPECT Radiotracer. B KOREAN CHEM SOC 2016. [DOI: 10.1002/bkcs.11027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Yingqing Lu
- Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology; Seoul National University; Seoul 08826 Korea
| | - Jae Ho Jung
- Department of Nuclear Medicine, Seoul National University College of Medicine; Seoul National University Bundang Hospital; Seongnam 13620 Korea
| | - Hong Jin Lee
- Department of Nuclear Medicine, Seoul National University College of Medicine; Seoul National University Bundang Hospital; Seongnam 13620 Korea
| | - Byung Seok Moon
- Department of Nuclear Medicine, Seoul National University College of Medicine; Seoul National University Bundang Hospital; Seongnam 13620 Korea
| | - Byung Chul Lee
- Department of Nuclear Medicine, Seoul National University College of Medicine; Seoul National University Bundang Hospital; Seongnam 13620 Korea
- Center for Nanomolecular Imaging and Innovative Drug Development; Advanced Institutes of Convergence Technology; Suwon 16229 Korea
| | - Sang Eun Kim
- Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology; Seoul National University; Seoul 08826 Korea
- Department of Nuclear Medicine, Seoul National University College of Medicine; Seoul National University Bundang Hospital; Seongnam 13620 Korea
- Center for Nanomolecular Imaging and Innovative Drug Development; Advanced Institutes of Convergence Technology; Suwon 16229 Korea
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6
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Rotstein BH, Liang SH, Placzek MS, Hooker JM, Gee AD, Dollé F, Wilson AA, Vasdev N. (11)C[double bond, length as m-dash]O bonds made easily for positron emission tomography radiopharmaceuticals. Chem Soc Rev 2016; 45:4708-26. [PMID: 27276357 PMCID: PMC5000859 DOI: 10.1039/c6cs00310a] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The positron-emitting radionuclide carbon-11 ((11)C, t1/2 = 20.3 min) possesses the unique potential for radiolabeling of any biological, naturally occurring, or synthetic organic molecule for in vivo positron emission tomography (PET) imaging. Carbon-11 is most often incorporated into small molecules by methylation of alcohol, thiol, amine or carboxylic acid precursors using [(11)C]methyl iodide or [(11)C]methyl triflate (generated from [(11)C]carbon dioxide or [(11)C]methane). Consequently, small molecules that lack an easily substituted (11)C-methyl group are often considered to have non-obvious strategies for radiolabeling and require a more customized approach. [(11)C]Carbon dioxide itself, [(11)C]carbon monoxide, [(11)C]cyanide, and [(11)C]phosgene represent alternative reactants to enable (11)C-carbonylation. Methodologies developed for preparation of (11)C-carbonyl groups have had a tremendous impact on the development of novel PET tracers and provided key tools for clinical research. (11)C-Carbonyl radiopharmaceuticals based on labeled carboxylic acids, amides, carbamates and ureas now account for a substantial number of important imaging agents that have seen translation to higher species and clinical research of previously inaccessible targets, which is a testament to the creativity, utility and practicality of the underlying radiochemistry.
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Affiliation(s)
| | - Steven H Liang
- Massachusetts General Hospital, Harvard Medical School, Boston, USA.
| | - Michael S Placzek
- Athinoula A. Martinos Center for Biomedical Imaging, MGH, HMS, Charlestown, USA and McLean Hospital, Belmont, USA
| | - Jacob M Hooker
- Athinoula A. Martinos Center for Biomedical Imaging, MGH, HMS, Charlestown, USA
| | | | - Frédéric Dollé
- CEA - Institut d'imagerie biomédicale, Service hospitalier Frédéric Joliot, Université Paris-Saclay, Orsay, France
| | - Alan A Wilson
- Centre for Addiction and Mental Health, Toronto, Canada
| | - Neil Vasdev
- Massachusetts General Hospital, Harvard Medical School, Boston, USA.
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7
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Eckelman WC, Dilsizian V. Chemistry and biology of radiotracers that target changes in sympathetic and parasympathetic nervous systems in heart disease. J Nucl Med 2015; 56 Suppl 4:7S-10S. [PMID: 26033907 DOI: 10.2967/jnumed.114.142802] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Following the discovery of the sympathetic and parasympathetic nervous system, numerous adrenoceptor drugs were radiolabeled and potent radioligands were prepared in order to image the β-adrenergic and the muscarinic systems. But the greatest effort has been in preparing noradrenaline analogs, such as norepinephrine, (11)C-metahydroxyephedrine, and (123)I-metaiodobenzylguanidine that measure cardiac sympathetic nerve varicosities. Given the technical and clinical challenges in designing and validating targeted adrenoceptor-binding radiotracers, namely the heavily weighted flow dependence and relatively low target-to-background ratio, both requiring complicated mathematic analysis, and the inability of targeted adrenoceptor radioligands to have an impact on clinical care of heart disease, the emphasis has been on radioligands monitoring the norepinephrine pathway. The chemistry and biology of such radiotracers, and the clinical and prognostic impact of these innervation imaging studies in patients with heart disease, are examined.
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Affiliation(s)
| | - Vasken Dilsizian
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland
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8
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Yu J, Gao C, Song Z, Yang H, Fu H. Metal-Free Oxidative C-H Amidation ofN,N′-Diarylureas with PhI(OAc)2: Synthesis of Benzimidazol-2-one Derivatives. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500726] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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9
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Chen X, Werner RA, Javadi MS, Maya Y, Decker M, Lapa C, Herrmann K, Higuchi T. Radionuclide imaging of neurohormonal system of the heart. Am J Cancer Res 2015; 5:545-58. [PMID: 25825596 PMCID: PMC4377725 DOI: 10.7150/thno.10900] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 01/02/2015] [Indexed: 12/18/2022] Open
Abstract
Heart failure is one of the growing causes of death especially in developed countries due to longer life expectancy. Although many pharmacological and instrumental therapeutic approaches have been introduced for prevention and treatment of heart failure, there are still limitations and challenges. Nuclear cardiology has experienced rapid growth in the last few decades, in particular the application of single photon emission computed tomography (SPECT) and positron emission tomography (PET), which allow non-invasive functional assessment of cardiac condition including neurohormonal systems involved in heart failure; its application has dramatically improved the capacity for fundamental research and clinical diagnosis. In this article, we review the current status of applying radionuclide technology in non-invasive imaging of neurohormonal system in the heart, especially focusing on the tracers that are currently available. A short discussion about disadvantages and perspectives is also included.
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Mamedov VA, Zhukova NA, Zamaletdinova AI, Beschastnova TN, Kadyrova MS, Rizvanov IK, Syakaev VV, Latypov SK. Reaction for the synthesis of benzimidazol-2-ones, imidazo[5,4-b]-, and imidazo[4,5-c]pyridin-2-ones via the rearrangement of quinoxalin-2-ones and their aza analogues when exposed to enamines. J Org Chem 2014; 79:9161-9. [PMID: 25203611 DOI: 10.1021/jo501526a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A synthetically useful protocol has been developed for the preparation of highly functionalized N-pyrrolylbenzimidazol-2-ones. The reaction of variously substituted 3-aroyl- and 3-alkanoylquinoxalin-2(1H)-ones with commercially available enamines in acetic acid results in a rapid rearrangement and formation of N-pyrrolylbenzimidazol-2-ones in modest to excellent yields. The key step of the rearrangement involves the novel ring contraction of 3-aroyl- and 3-alkanoylquinoxalin-2(1H)-ones with enamines. In this case, the atom of carbon which is displaced from the pyrazine ring of quinoxalin-2(1H)-one becomes the fourth carbon atom of the newly formed pyrrole ring. The method is applicable for the aza analogues of quinoxalin-2(1H)-ones.
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Affiliation(s)
- Vakhid A Mamedov
- A.E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Center of the Russian Academy of Sciences , Arbuzov str. 8, Kazan 420088, Russian Federation
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11
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Khanapur S, Paul S, Shah A, Vatakuti S, Koole MJB, Zijlma R, Dierckx RAJO, Luurtsema G, Garg P, van Waarde A, Elsinga PH. Development of [18F]-labeled pyrazolo[4,3-e]-1,2,4- triazolo[1,5-c]pyrimidine (SCH442416) analogs for the imaging of cerebral adenosine A2A receptors with positron emission tomography. J Med Chem 2014; 57:6765-80. [PMID: 25061687 DOI: 10.1021/jm500700y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cerebral adenosine A2A receptors (A2ARs) are attractive therapeutic targets for the treatment of neurodegenerative and psychiatric disorders. We developed high affinity and selective compound 8 (SCH442416) analogs as in vivo probes for A2ARs using PET. We observed the A2AR-mediated accumulation of [18F]fluoropropyl ([18F]-10b) and [18F]fluoroethyl ([18F]-10a) derivatives of 8 in the brain. The striatum was clearly visualized in PET and in vitro autoradiography images of control animals and was no longer visible after pretreatment with the A2AR subtype-selective antagonist KW6002. In vitro and in vivo metabolite analyses indicated the presence of hydrophilic (radio)metabolite(s), which are not expected to cross the blood-brain-barrier. [18F]-10b and [18F]-10a showed comparable striatum-to- cerebellum ratios (4.6 at 25 and 37 min post injection, respectively) and reversible binding in rat brains. We concluded that these compounds performed equally well, but their kinetics were slightly different. These molecules are potential tools for mapping cerebral A2ARs with PET.
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Affiliation(s)
- Shivashankar Khanapur
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen , Groningen, The Netherlands
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12
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Ernst JB, Tay NES, Jui NT, Buchwald SL. Regioselective synthesis of benzimidazolones via cascade C-N coupling of monosubstituted ureas. Org Lett 2014; 16:3844-6. [PMID: 24971635 PMCID: PMC4216194 DOI: 10.1021/ol501531q] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
![]()
A direct
method for the regioselective construction of benzimidazolones
is reported wherein a single palladium catalyst is employed to couple
monosubstituted urea substrates with differentially substituted 1,2-dihaloaromatic
systems. In this method, the catalyst is able to promote a cascade
of two discrete chemoselective C–N bond-forming processes that
allows the highly selective and predictable formation of complex heterocycles
from simple, readily available starting materials.
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Affiliation(s)
- Johannes B Ernst
- Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
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13
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Sakr TM, Moustapha ME, Motaleb MA. 99mTc-nebivolol as a novel heart imaging radiopharmaceutical for myocardial infarction assessment. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2168-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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14
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El-Tawoosy M, Ibrahim IT. Radioiodination and biological evaluation of salbutamol as a β2-adrenoceptor agonist. RADIOCHEMISTRY 2012. [DOI: 10.1134/s1066362212040169] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Amin AM. Iodine-125-terbutaline (125ITB): a new β2-adrenoceptor probe for lung imaging. J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.2935] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- A. M. Amin
- Labeled Compounds Department; Hot Lab. Center; Atomic Energy Authority; 13759; Cairo; Egypt
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16
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Elsinga PH, Doze P, Maas B, Van Waarde A, Wegman T, Vaalburg W. Synthesis and evaluation of radiolabelled antagonists for beta-adrenoceptor imaging in the brain with pet. J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.2580440192] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Stephenson KA, Wilson AA, Houle S, Vasdev N. Synthesis and in vitro evaluation of derivatives of the β1-adrenergic receptor antagonist HX-CH 44. Bioorg Med Chem Lett 2011; 21:5506-9. [PMID: 21783363 DOI: 10.1016/j.bmcl.2011.06.106] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 06/22/2011] [Accepted: 06/24/2011] [Indexed: 10/18/2022]
Affiliation(s)
- Karin A Stephenson
- PET Centre, Centre for Addiction and Mental Health, Department of Psychiatry, University of Toronto, 250 College St., Toronto, Ontario, Canada M5T 1R8
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18
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Beyer A, Reucher CMM, Bolm C. Potassium hydroxide/dimethyl sulfoxide promoted intramolecular cyclization for the synthesis of benzimidazol-2-ones. Org Lett 2011; 13:2876-9. [PMID: 21534616 DOI: 10.1021/ol2008878] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new protocol for intramolecular N-arylations of ureas to form benzimidazol-2-ones has been developed. The cyclization reaction occurs in the presence of KOH and DMSO at close to ambient temperature. Under these conditions the yields are high and a wide range of functional groups are tolerated.
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Affiliation(s)
- Astrid Beyer
- Institute of Organic Chemistry, RWTH Aachen University, Aachen, Germany
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19
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Motaleb MA, Moustapha ME, Ibrahim IT. Synthesis and biological evaluation of 125I-nebivolol as a potential cardioselective agent for imaging β1-adrenoceptors. J Radioanal Nucl Chem 2011. [DOI: 10.1007/s10967-011-1069-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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20
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Maruyama T, Onda K, Hayakawa M, Seki N, Takahashi T, Moritomo H, Suzuki T, Matsui T, Takasu T, Nagase I, Ohta M. Synthesis and evaluation of novel phenoxypropanolamine derivatives containing acetanilides as potent and selective β3-adrenergic receptor agonists. Bioorg Med Chem 2009; 17:3283-94. [DOI: 10.1016/j.bmc.2009.03.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 03/23/2009] [Accepted: 03/24/2009] [Indexed: 11/17/2022]
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21
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18F-labelled cardiac PET tracers: selected probes for the molecular imaging of transporters, receptors and proteases. Basic Res Cardiol 2008; 103:131-43. [DOI: 10.1007/s00395-008-0703-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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van Waarde A, Doorduin J, de Jong JR, Dierckx RA, Elsinga PH. Synthesis and preliminary evaluation of (S)-[11C]-exaprolol, a novel β-adrenoceptor ligand for PET. Neurochem Int 2008; 52:729-33. [DOI: 10.1016/j.neuint.2007.09.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Accepted: 09/03/2007] [Indexed: 10/22/2022]
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Abstract
The aberrant expression and function of certain receptors in tumours and other diseased tissues make them preferable targets for molecular imaging. PET and SPECT radionuclides can be used to label specific ligands with high affinity for the target receptors. The functional information obtained from imaging these receptors can be used to better understand the systems under investigation and for diagnostic and therapeutic applications. This review discusses some of the aspects of receptor imaging with small molecule tracers by PET and SPECT and reviews some of the tracers for the receptor imaging of tumours and brain, heart and lung disorders.
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Affiliation(s)
- Aviv Hagooly
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., Campus Box 8225, St. Louis, MO 63110, USA.
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Abstract
In recent years, the importance of alterations of cardiac autonomic nerve function in the pathophysiology of heart diseases including heart failure, arrhythmia, ische-mic heart disease, and diabetes has been increasingly recognized. Several radiolabeled compounds have been synthesized for noninvasive imaging, including single photon emission CT and positron emission tomography (PET). The catecholamine analogue I-123 metaiodobenzylguanidine (MIBG) is the most commonly used tracer for mapping of myocardial presynaptic sympathetic innervation on a broad clinical basis. In addition, radiolabeled catecholamines and catecholamine analogues are available for PET imaging, which allows absolute quantification and tracer kinetics modeling. Postsynaptic receptor PET imaging added new insights into mechanisms of heart disease. These advanced imaging techniques provide noninvasive, repeatable in vivo information of autonomic nerve function in the human heart and are promising for providing profound insights into molecular pathophysiology, monitoring of treatment, and determination of individual outcome.
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Affiliation(s)
- Takahiro Higuchi
- Nuklearmedizinische Klinik und Poliklinik, Klinikum Rechts der Isar der Technischen Universität München, Ismaninger Strasse 22, 81675 München, Germany
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Lautamäki R, Tipre D, Bengel FM. Cardiac sympathetic neuronal imaging using PET. Eur J Nucl Med Mol Imaging 2007; 34 Suppl 1:S74-85. [PMID: 17479262 DOI: 10.1007/s00259-007-0442-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Balance of the autonomic nervous system is essential for adequate cardiac performance, and alterations seem to play a key role in the development and progression of various cardiac diseases. PET AS AN IMAGING TOOL PET imaging of the cardiac autonomic nervous system has advanced extensively in recent years, and multiple pre- and postsynaptic tracers have been introduced. The high spatial and temporal resolution of PET enables noninvasive quantification of neurophysiologic processes at the tissue level. Ligands for catecholamine receptors, along with radiolabeled catecholamines and catecholamine analogs, have been applied to determine involvement of sympathetic dysinnervation at different stages of heart diseases such as ischemia, heart failure, and arrhythmia. REVIEW This review summarizes the recent findings in neurocardiological PET imaging. Experimental studies with several radioligands and clinical findings in cardiac dysautonomias are discussed.
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Affiliation(s)
- Riikka Lautamäki
- Division of Nuclear Medicine, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, USA
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Nishijima KI. A Study on the Highly Efficient Synthesis and Pharmaceutical Evaluation of PET Radiopharmaceuticals for the Clinical Application. YAKUGAKU ZASSHI 2006; 126:737-45. [PMID: 16946587 DOI: 10.1248/yakushi.126.737] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Positron Emission Tomography (PET) is an advanced non-invasive technology used in the field of nuclear medicine for clinical diagnosis using radiotracers labeled with short-lived positron emitting radionuclides such as (11)C (half-life: 20.4 min), (13)N, (15)O and (18)F. The present study describes an efficient rapid synthesis method for [(11)C]Phosgene ([(11)C]COCl(2)) which is an important potential precursor for preparation of PET radiopharmaceuticals. Catalytic oxidation of [(11)C]CCl(4) using Fe(2)O(3) powder mixed with Fe granules as an oxidizing agent was newly accomplished with a development of fully automated synthetic apparatus. Utilization of produced [(11)C]COCl(2) provided a substantial synthesis of [2-(11)C]thymine as a key intermediate for preparation of [2-(11)C]thymidine, a PET tracer to evaluate cellular proliferation. Direct ring closure reaction of the alkali metal salt of beta-(N-benzoyl-amino)methacrylamide with [(11)C]COCl(2) readily proceeded under mild conditions to afford [2-(11)C]thymine in fair yield reproducibly. By way of further application, a useful PET ligand for beta-adrenoreceptors, S-(-)-[(11)C]CGP-12177 (CGP) was synthesized in markedly high yield with high specific activity and radiochemical purity. CGP for intravenous injection was prepared in 25 min after EOB with a yield of 1.5+/-0.2 GBq. These results of quality control tests demonstrated that CGP preparation is suitable for routine clinical use. Thus, CGP-PET study has been newly added to clinical PET for cardiac functional investigation in Hokkaido University Hospital.
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Affiliation(s)
- Ken-ichi Nishijima
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Japan.
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Higuchi T, Schwaiger M. Noninvasive Imaging of Heart Failure: Neuronal Dysfunction and Risk Stratification. Heart Fail Clin 2006; 2:193-204. [PMID: 17386889 DOI: 10.1016/j.hfc.2006.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Takahiro Higuchi
- Nuklearmedizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität München, München, Germany
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Wagner S, Law MP, Riemann B, Pike VW, Breyholz HJ, Höltke C, Faust A, Renner C, Schober O, Schäfers M, Kopka K. Synthesis of an18F-labelled high affinityβ1-adrenoceptor PET radioligand based on ICI 89,406. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.1037] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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van Waarde A, Maas B, Doze P, Slart RH, Frijlink HW, Vaalburg W, Elsinga PH. Positron Emission Tomography Studies of Human Airways Using an Inhaled β-Adrenoceptor Antagonist, S-11 C-CGP 12388. Chest 2005; 128:3020-7. [PMID: 16236982 DOI: 10.1378/chest.128.4.3020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
OBJECTIVES Positron emission tomography (PET) scanning may provide information on changes in the density and affinity of airway beta-adrenoceptors in lung diseases. However, the injection of a radiolabeled beta-blocker results in a pulmonary PET signal that reflects the binding of the ligand in the alveoli and not in the airways. Better discrimination between alveolar and airway beta-adrenoceptors may be possible with an inhaled radioligand. DESIGN A nebulizer was used to administer the antagonist S-11C-CGP12388 in aerosol form. Eight volunteers inhaled the tracer twice, at baseline and after pretreatment with a beta-adrenergic drug. In both PET scan studies, a dynamic scan of the lungs was followed by a whole-body scan to assess the inhaled dose. Pulmonary uptake was quantified using a region-of-interest-based analysis. SETTING University hospital. PARTICIPANTS Healthy volunteers. INTERVENTIONS Pretreatment consisted either of inhaled salbutamol (400 microg, 20 min before the scan), or orally administered pindolol (3 x 5 mg during a period of 16 h before PET scanning). RESULTS Drug pretreatment did not affect pulmonary deposition of the radioligand. The agonist salbutamol accelerated the monoexponential washout of 11C not only in the peripheral lung (mainly alveoli), but also in the central lung (mainly airways) and in the main bronchi. An even larger increase of the washout rate was induced by the antagonist pindolol. CONCLUSION The similar effects of pindolol and salbutamol on tracer kinetics suggest that accelerated washout is due to the blockade of beta-adrenoceptors. Thus, the interaction of drugs with airway beta-adrenoceptors can be visualized using PET scanning and an inhaled radioligand.
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Affiliation(s)
- Aren van Waarde
- Department of Internal Medicine & Molecular Imaging, University Medical Center of Groningen, PO Box 30001, 9700RB Groningen, Netherlands.
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Zhang MR, Ogawa M, Yoshida Y, Suzuki K. Selective synthesis of [2-(11)C]2-iodopropane and [1-(11)C]iodoethane using the loop method by reacting methylmagnesium bromide with [11C]carbon dioxide. Appl Radiat Isot 2005; 64:216-22. [PMID: 16194603 DOI: 10.1016/j.apradiso.2005.07.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2005] [Revised: 07/08/2005] [Accepted: 07/23/2005] [Indexed: 10/25/2022]
Abstract
[2-(11)C]2-iodopropane ([2-(11)C]i-PrI) and [1-(11)C]iodoethane ([1-(11)C]EtI) were selectively synthesized using the loop method by reacting methylmagnesium bromide (MeMgBr) with [11C]carbon oxide ([11C]CO2), followed by treatment with LiAlH4 and then HI. The loop method, in which a low amount of MeMgBr was used for the Grignard reaction, diminished the formation of non-radioactive iodomethane (MeI) and improved the specific activity of [2-(11)C]i-PrI and [1-(11)C]EtI. By examining the reaction temperature and time of MeMgBr with [11C]CO2 in the loop, we determined the optimal respective conditions of forming [2-(11)C]i-PrI and [1-(11)C]EtI. Moreover, [2-(11)C]i-PrI and [1-(11)C]EtI could be simultaneously synthesized at a designated ratio in one production run. These substances were obtained by gas chromatographic purification as two radiochemically pure products. All the processes from the production of [11C]CO2 to the purification of [11C]RI were automated. When we started from about 37 GBq of [11C]CO2, 3.9-5.3 GBq of [1-(11)C]EtI or 3.7-4.4 GBq of [2-(11)C]i-PrI was obtained with a specific activity of 37-99 GBq/micromol at EOS (n=3). This amount of radioactivity is sufficient for the synthesis of [11C]radioligands.
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Affiliation(s)
- Ming-Rong Zhang
- Department of Medical Imaging, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan
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Nishijima K, Kuge Y, Seki K, Ohkura K, Morita K, Nakada K, Tamaki N. Preparation and pharmaceutical evaluation for clinical application of high specific activity S-(-)[11C]CGP-12177, a radioligand for beta-adrenoreceptors. Nucl Med Commun 2005; 25:845-9. [PMID: 15266181 DOI: 10.1097/01.mnm.0000134320.39903.75] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Although S-(-)[C]CGP-12177 is a useful positron emission tomography (PET) ligand for beta-adrenoreceptors, the difficulty in radiolabelling the compound has prevented its extensive clinical application. Recently, we have developed a simple synthesis method for S-(-)[C]CGP-12177. In the present study, we attempted to prepare S-(-)[C]CGP-12177 with a high specific activity for intravenous injection which is feasible for the clinical evaluation of beta-adrenoreceptors. METHODS The [C]methane produced during irradiation of a N2--H2 (95/5) mixture with an 18 MeV proton beam (20 microA, 30 min) was chlorinated using Cl2 to yield [C]carbon tetrachloride. S-(-)[C]CGP-12177 was synthesized by reacting the diamino precursor with [C]phosgene produced by oxidizing [C]carbon tetrachloride on a Fe--Fe2O3 column. The product was purified by using reversed phase, high-performance liquid chromatography (RP-HPLC) and the radioactive fraction containing S-(-)[C]CGP-12177 was collected and evaporated to dryness. S-(-)[C]CGP-12177 dissolved in physiological saline was sterilized through a 0.22 microm membrane filter. The radiochemical purity and the mass of the compound were determined with RP-HPLC. The residual organic solvents were determined with GC. Tests for sterility and the presence of bacterial endotoxins were also performed. RESULTS S-(-)[C]CGP-12177 for intravenous injection was prepared in 25 min after the end of bombardment with a yield of 1.5+/-0.2 GBq. Specific activity was found to be 385.4+/-133.0 GBq/ micromol at the end of synthesis (EOS) (n=3). Radiochemical purity was found to be more than 99%. Toluene was not detected in the solution. The ethanol concentration was determined to be 60.3+/-52.5 ppm. Tests for sterility and bacterial endotoxins showed negative results. CONCLUSION We successfully prepared S-(-)[C]CGP-12177 formulated for intravenous injection with high purity and high specific activity, which is feasible for the clinical evaluation of beta-adrenoreceptors.
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Affiliation(s)
- K Nishijima
- Department of Tracer Kinetics and Department of Nuclear Medicine, Graduate School of Medicine, Hokkaido University, Sapporo, Japan
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Elsinga PH, van Waarde A, Vaalburg W. Receptor imaging in the thorax with PET. Eur J Pharmacol 2005; 499:1-13. [PMID: 15363946 DOI: 10.1016/j.ejphar.2004.06.057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2004] [Revised: 06/23/2004] [Accepted: 06/29/2004] [Indexed: 10/26/2022]
Abstract
This review focuses on positron emission tomography (PET)-imaging of receptors in the sympathetic and the parasympathetic systems of heart and lung and highlights the human applications of PET. For the alpha-adrenoceptor, only [11C]GB67 (N2-[6-[(4-amino-6,7-dimethoxy-2-quinazolinyl)(methyl)amino]hexyl]-N2-[11C]methyl-2-furamide hydrochloride) has been developed. Its potential for application in patients needs to be assessed. For both the beta-adrenergic and the muscarinic systems, potent PET radioligands have been prepared and evaluated in patients. It has been possible to measure receptor densities quantitatively in human heart [[11C]MQNB: [11C]methylquinuclidinyl benzilate, [11C]CGP12177: S-(3'-t-butylamino-2'-hydroxypropoxy)-benzimidazol-2-[11C]one and [11C]CGP12388: (S)-4-(3-(2'-[11C]isopropylamino)-2-hydroxypropoxy)-2H-benzimidazol-2-one] and qualitatively in lung [[11C]VC002: N-[11C]-methyl-piperidin-4-yl-2-cyclohexyl-2-hydroxy-2-phenylacetate and [11C]CGP12177]. Besides these subtype nonselective radioligands, the development of compounds that are selective for one subtype are ongoing and have not found successful application in humans yet.
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Affiliation(s)
- Philip H Elsinga
- Groningen University Hospital, PET-center, P.O. Box 30001, 9700 RB Groningen, The Netherlands.
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de Jong RM, Willemsen ATM, Slart RHJA, Blanksma PK, van Waarde A, Cornel JH, Vaalburg W, van Veldhuisen DJ, Elsinga PH. Myocardial beta-adrenoceptor downregulation in idiopathic dilated cardiomyopathy measured in vivo with PET using the new radioligand (S)-[11C]CGP12388. Eur J Nucl Med Mol Imaging 2004; 32:443-7. [PMID: 15592928 DOI: 10.1007/s00259-004-1701-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2004] [Accepted: 09/09/2004] [Indexed: 01/08/2023]
Abstract
PURPOSE The beta-adrenoceptor (beta-AR) plays an important role in heart failure. Recently, the new tracer (S)-[11C]CGP12388 has been developed. It displays excellent properties for investigation of the cardiac beta-ARs in vivo with positron emission tomography (PET). Furthermore, the simple production method allows its use in a routine clinical setting. The aim of this study was to investigate whether decreased myocardial beta-AR density in patients with idiopathic dilated cardiomyopathy (IDC) can be estimated using (S)-[11C]CGP12388 PET. METHODS Myocardial beta-AR density was investigated in six patients with IDC and six age-matched healthy controls, using (S)-[11C]CGP12388 PET. RESULTS Beta-AR densities of 5.4+/-1.3 pmol/g (mean +/- SD) were observed in patients; these values were significantly lower than those observed in healthy controls (8.4+/-1.5 pmol/g, p<0.005). CONCLUSION This study indicates that PET with (S)-[11C]CGP12388 is applicable for the measurement of myocardial beta-AR density in patients. A highly significant reduction in beta-AR density was found in patients with IDC compared with healthy controls.
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Affiliation(s)
- Richard M de Jong
- Deparment of Cardiology, Groningen University Hospital, Groningen, The Netherlands
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Abstract
The autonomic nervous system plays a key role for regulation of cardiac performance, and the importance of alterations of innervation in the pathophysiology of various heart diseases has been increasingly emphasized. Nuclear imaging techniques have been established that allow for global and regional investigation of the myocardial nervous system. The guanethidine analog iodine 123 metaiodobenzylguanidine (MIBG) has been introduced for scintigraphic mapping of presynaptic sympathetic innervation and is available today for imaging on a broad clinical basis. Not much later than MIBG, positron emission tomography (PET) has also been established for characterizing the cardiac autonomic nervous system. Although PET is methodologically demanding and less widely available, it provides substantial advantages. High spatial and temporal resolution along with routinely available attenuation correction allows for detailed definition of tracer kinetics and makes noninvasive absolute quantification a reality. Furthermore, a series of different radiolabeled catecholamines, catecholamine analogs, and receptor ligands are available. Those are often more physiologic than MIBG and well understood with regard to their tracer physiologic properties. PET imaging of sympathetic neuronal function has been successfully applied to gain mechanistic insights into myocardial biology and pathology. Available tracers allow dissection of processes of presynaptic and postsynaptic innervation contributing to cardiovascular disease. This review summarizes characteristics of currently available PET tracers for cardiac neuroimaging along with the major findings derived from their application in health and disease.
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Affiliation(s)
- Frank M Bengel
- Nuklearmedizinische Klinik der Technischen Universität Müchen, 81675 Munich, Germany.
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Soma LR, Uboh CE, Guan F, Luo Y, Teleis D, Runbo L, Birks EK, Tsang DS, Habecker P. Tissue distribution of clenbuterol in the horse. J Vet Pharmacol Ther 2004; 27:91-8. [PMID: 15096106 DOI: 10.1111/j.1365-2885.2004.00558.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Plasma and tissue concentrations of clenbuterol (CLB) were determined following oral (p.o.) administration of 1.6 microg/kg twice daily (b.i.d.) for 2 weeks. Horses were administered the last dose on morning of day 15, killed at 0.25, 24, 48, and 72 h post-administration. At 0.25 h, the highest tissue concentrations of CLB were found in the liver (16.21 ng/g), lung (6.48 ng/g), left ventricle (4.99 ng/g), kidney (3.35 ng/g), bronchi (2.56 ng/g), right ventricle (2.08 ng/g), and eye fluids (1.09 ng/g) all of which were higher than that of plasma (1.10 ng/mL). The elimination half-lives (t(1/2k)) for CLB in tissues ranged from 21.2 to 56.3 h, the longest were in the eye fluids (56.9 h), spleen (21.2 h), cerebrum (27.1 h), cerebellum (21.5) and cecum (23.7 h). The t(1/2k) for plasma was 10.9 h. Tissue/plasma ratios of liver (14.7), lung (5.9), left ventricle (4.6), kidney (3.1), bronchi, (2.3) and right ventricle (1.9) were high at 0.25 h and remained elevated up to 72 h. Accumulation and sustained high concentration of CLB relative to plasma in these tissues contributed to the prolonged elimination and the ability to quantify CLB in plasma and urine for a prolonged period.
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Affiliation(s)
- L R Soma
- School of Veterinary Medicine, University of Pennsylvania, New Bolton Center Campus, West Street Road, Kennett Square, PA 19348, USA.
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Roger G, Lagnel B, Besret L, Bramoullé Y, Coulon C, Ottaviani M, Kassiou M, Bottlaender M, Valette H, Dollé F. Synthesis, radiosynthesis and In vivo evaluation of 5-[3-(4-Benzylpiperidin-1-yl)prop-1-ynyl]-1,3-dihydrobenzoimidazol-2-[11C]one, as a potent NR1A/2B subtype selective NMDA PET radiotracer. Bioorg Med Chem 2003; 11:5401-8. [PMID: 14642584 DOI: 10.1016/j.bmc.2003.09.036] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Recently, a new series of potent and highly subtype-selective 1-(heteroarylalkynyl)-4-benzylpiperidine antagonists of the NMDA receptors has been described by Pfizer Laboratories. In this series, 5-[3-(4-benzylpiperidin-1-yl)prop-1-ynyl]-1,3-dihydrobenzoimidazol-2-one (1) was identified as a selective antagonist for the NR1(A)/2B subtype, displaying IC(50) values for inhibition of the NMDA responses of 5.3 nM for this subtype (compared to NR1(A)/2A: 35 microM and NR1(A)/2C>100 microM) and was active in rat at a relatively low dosage (10mg/kg po). Derivative 1 has been synthesized in four chemical steps in good overall yield and labelled with carbon-11 at its benzoimidazolone ring using [(11)C]phosgene. The pharmacological profile of [(11)C]-1 was evaluated in vivo in rats with biodistribution studies and brain radioactivity monitored with intracerebral radiosensitive beta-microprobes. The brain uptake of [(11)C]-1 was extremely low (0.07% I.D./mL on average at 30 min) and rather uniform across the different brain structures. This in vivo brain regional distribution of [(11)C]-1 did not match with autoradiographic or binding data obtained with other NR2B subtype-selective NMDA ligands. Competition studies with ifenprodil (20 mg/kg, ip, 30 min before the radiotracer injection) failed to demonstrate specific binding of the radiotracer in the brain. In view of these results, and especially considering the low brain penetration of the radiotracer, [(11)C]-1 does not have the required properties for imaging NMDA receptors using positron emission tomography.
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Affiliation(s)
- Gaëlle Roger
- Département de Recherche Médicale, CEA/DSV, 4 Place du Général Leclerc, F-91401 Orsay, France
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Schirrmacher E, Schirrmacher R, Thews O, Dillenburg W, Helisch A, Wessler I, Buhl R, Höhnemann S, Buchholz HG, Bartenstein P, Machulla HJ, Rösch F. Synthesis and preliminary evaluation of (R,R)(S,S) 5-(2-(2-[4-(2-[(18)F]fluoroethoxy)phenyl]-1-methylethylamino)-1-hydroxyethyl)-benzene-1,3-diol ([(18)F]FEFE) for the in vivo visualisation and quantification of the beta2-adrenergic receptor status in lung. Bioorg Med Chem Lett 2003; 13:2687-92. [PMID: 12873495 DOI: 10.1016/s0960-894x(03)00538-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The (18)F-labeled beta2-adrenergic receptor ligand (R,R)(S,S) 5-(2-(2-[4-(2-[(18)F]fluoroethoxy)phenyl]-1-methylethylamino)-1-hydroxyethyl)-benzene-1,3-diol, a derivative of the original highly selective racemic fenoterol, was synthesized in an overall radiochemical yield of 20% after 65 min with a radiochemical purity higher than 98%. The specific activity was in the range of 50-60 GBq/micromol. In vitro testing of the non-radioactive fluorinated fenoterol derivative with isolated guinea pig trachea was conducted to obtain an IC(50) value of 60 nM. Preliminary ex vivo organ distribution and in vivo experiments with positron emission tomography (PET) on guinea pigs were performed to study the biodistribution as well as the displacement of the radiotracer to prove specific binding to the beta2-receptor.
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Affiliation(s)
- Esther Schirrmacher
- Institute of Nuclear Chemistry, University of Mainz, Fritz Strassmann-Weg 2, D-55128, Mainz, Germany.
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van der Meij M, Carruthers NI, Herscheid JD, Jablonowski JA, Leysen JE, Windhorst AD. ReductiveN-alkylation of secondary amines with [2-11C]acetone. J Labelled Comp Radiopharm 2003. [DOI: 10.1002/jlcr.740] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Matarrese M, Moresco RM, Romeo G, Turolla EA, Simonelli P, Todde S, Belloli S, Carpinelli A, Magni F, Russo F, Galli Kienle M, Fazio F. [11C]RN5: a new agent for the in vivo imaging of myocardial alpha1-adrenoceptors. Eur J Pharmacol 2002; 453:231-8. [PMID: 12398909 DOI: 10.1016/s0014-2999(02)02454-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The radiolabelling with the positron-emitter Carbon-11 and the biological evaluation in rats of 3-[2-[4-(2-[11C]methoxyphenyl)piperazin-1-yl]ethyl]pyrimido[5,4-b]indole-2,4-dione ([11C]RN5), alpha1-adrenoceptor antagonist (K(i)=0.21 nM), as a putative radioligand for the non-invasive assessment of alpha1-adrenoceptors with positron emission tomography (PET) is reported. The radiosynthesis procedure consisted of O-methylation of des-methyl precursor with [11C]methyl iodide in the presence of potassium hydroxide in dimethylformamide (DMF) at 80 degrees C. [11C]RN5 was obtained in >99% radiochemical purity in 25 min with a radiochemical yield in the 20-30% range, end of synthesis (EOS) (non-decay corrected) and a specific radioactivity of 92.5+/-18.5 GBq/micromol. Pre-clinical studies in rats showed a high uptake of [11C]RN5 in heart, spleen, adrenal gland, lung and kidney but not in the brain. Inhibition studies with high doses of different adrenergic antagonists indicate that more than 70% of myocardial uptake of [11C]RN5 is due to specific binding to alpha1-adrenoceptors. Our results indicate that [11C]RN5 is suitable to be further developed as a potential radioligand for the in vivo PET imaging of myocardial alpha1-adrenoceptors in humans.
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Affiliation(s)
- Mario Matarrese
- Institute of Molecular Bioimaging and Physiology-CNR, University of Milano/Bicocca, Institute San Raffaele, Via Olgettina 60, 20132, Milan, Italy
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Steffan RJ, Ashwell MA, Solvibile WR, Matelan E, Largis E, Han S, Tillet J, Mulvey R. Novel substituted 4-aminomethylpiperidines as potent and selective human β3-agonists. Part 1: aryloxypropanolaminomethylpiperidines. Bioorg Med Chem Lett 2002; 12:2957-61. [PMID: 12270183 DOI: 10.1016/s0960-894x(02)00607-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The synthesis and SAR of a series of human beta3 adrenoreceptor agonists based on a template derived from a common pharmacophore coupled with 4-aminomethylpiperidine is described. Potent and selective agents were identified such as 26 that was in vitro active in CHO cells expressing human beta3-AR (EC50=49 nM, IA=1.1), and in vivo active in a transgenic mouse model.
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Affiliation(s)
- Robert J Steffan
- Chemical Sciences, Wyeth Research, 500 Arcola Rd, Collegeville, PA 19426, USA.
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Doze P, Elsinga PH, Maas B, Van Waarde A, Wegman T, Vaalburg W. Synthesis and evaluation of radiolabeled antagonists for imaging of beta-adrenoceptors in the brain with PET. Neurochem Int 2002; 40:145-55. [PMID: 11738481 DOI: 10.1016/s0197-0186(01)00081-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Five potent, lipophilic beta-adrenoceptor antagonists (carvedilol, pindolol, toliprolol and fluorinated analogs of bupranolol and penbutolol) were labeled with either carbon-11 or fluorine-18 and evaluated for cerebral beta-adrenoceptor imaging in experimental animals. The standard radioligand for autoradiography of beta-adrenoceptors, [125I]-iodocyanopindolol, was also included in this survey. All compounds showed either very low uptake in rat brain or a regional distribution that was not related to beta-adrenoceptors, whereas some ligands did display specific binding in heart and lungs. Apparently, the criteria of a high affinity and a moderately high lipophilicity were insufficient to predict the suitability of beta-adrenergic antagonists for visualization of beta-adrenoceptors in the central nervous system.
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Affiliation(s)
- Petra Doze
- PET-Center, Groningen University Hospital, P.O. Box 30.001, 9700 RB Groningen, The Netherlands
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42
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Elsinga PH, Doze P, van Waarde A, Pieterman RM, Blanksma PK, Willemsen AT, Vaalburg W. Imaging of beta-adrenoceptors in the human thorax using (S)-[(11)C]CGP12388 and positron emission tomography. Eur J Pharmacol 2001; 433:173-6. [PMID: 11755150 DOI: 10.1016/s0014-2999(01)01499-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We report positron emission tomography studies of beta-adrenoceptors in the human thorax with (S)-[(11)C]CGP12388 (4-(3-(2'-[(11)C]-isopropylamino)-2-hydroxypropoxy)-2H-benzimidazol-2-one). Beta-adrenoceptors have previously been quantified using (S)-[(11)C]CGP12177 (4-(3-tert-butylamino-2-hydroxypropoxy)-2H-benzimidazol-2[(11)C]-one), but (S)-[(11)C]CGP12388 is more easily prepared and therefore more suitable in a clinical setting. (S)-[(11)C]CGP12388 was administered to five healthy volunteers on two separate days (control and pindolol block study). Arterial plasma samples were used to determine clearance, metabolites, and protein binding of the radioligand. Heart, lung and spleen showed high uptake of radioactivity, which was strongly suppressed (68-77%) by pindolol. Plasma clearance of (S)-[(11)C]CGP12388 was rapid, binding to plasma proteins was low (53+/-4%), and the radioligand was slowly metabolized. (S)-[(11)C]CGP12388 produces high-quality images of the human thorax. Uptake of (S)-[(11)C]CGP12388 in heart, lung and spleen represents binding to beta-adrenoceptors. (S)-[(11)C]-CGP12388 seems useful for imaging of beta-adrenoceptors in a clinical setting.
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Affiliation(s)
- P H Elsinga
- PET-center, Groningen University Hospital, P.O. Box 30001, 9700 RB Groningen, The Netherlands.
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43
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Ashwell MA, Solvibile WR, Han S, Largis E, Mulvey R, Tillet J. 4-Aminopiperidine ureas as potent selective agonists of the human beta(3)-adrenergic receptor. Bioorg Med Chem Lett 2001; 11:3123-7. [PMID: 11720857 DOI: 10.1016/s0960-894x(01)00645-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The preparation and structure-activity relationships (SARs) of potent agonists of the human beta(3)-adrenergic receptor (AR) derived from a 4-aminopiperidine scaffold are described. Examples combine human beta(3)-AR potency with selectivity over human beta(1)-AR and/or human beta(2)-AR agonism. Compound 29s was identified as a potent (EC(50)=1nM) and selective (greater than 400-fold over beta(1)- with no beta(2)-AR agonism) full beta(3)-AR agonist with in vivo activity in a transgenic mouse model of thermogenesis.
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Affiliation(s)
- M A Ashwell
- Chemical Sciences, Wyeth-Ayerst Research, PO Box CN-8000, USA.
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44
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Eich K, Hammerle J, Kloiber W, Schwaiger M, Wester HJ. Development of a remote controlled synthesis apparatus for routine production of (S)-[11C]CGP 12388. J Labelled Comp Radiopharm 2001. [DOI: 10.1002/jlcr.25804401368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kumamoto T, Aoyama N, Nakano S, Ishikawa T, Narimatsu S. Synthesis of enantiomeric 4-hydroxypropranolols from 1,4-dihydroxynaphthalene. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0957-4166(01)00122-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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46
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Soloviev DV, Matarrese M, Moresco RM, Todde S, Bonasera TA, Sudati F, Simonelli P, Magni F, Colombo D, Carpinelli A, Kienle MG, Fazio F. Asymmetric synthesis and preliminary evaluation of (R)- and (S)-[11C]bisoprolol, a putative beta1-selective adrenoceptor radioligand. Neurochem Int 2001; 38:169-80. [PMID: 11137886 DOI: 10.1016/s0197-0186(00)00049-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
(+/-)-1-[4-(2-Isopropoxyethoxymethyl)-phenoxy]-3-isopropylamino-2-propanol (bisoprolol) is a potent, clinically used beta(1)-adrenergic agent. (R)-(+) and (S)-(-) enantiomers of bisoprolol were labelled with carbon-11 (t(1/2)=20.4 min) as putative tracers for the non-invasive assessment of the beta(1)-adrenoceptor subtype in the human heart and brain with positron emission tomography (PET). The radiosynthesis consisted of reductive alkylation of des-iso-propyl precursor with [2-11C]acetone in the presence of sodium cyanoborohydride and acetic acid. The stereo-conservative synthesis of (R)-(+) and (S)-(-)-1-[4-(2-isopropoxyethoxymethyl)-phenoxy]-3-amino-2-propanol to be used as the precursors for the radiosynthesis of [11C]bisoprolol enantiomers was readily accomplished by the use of the corresponding chiral epoxide in three steps starting from the commercially available hydroxybenzyl alcohol. The final labelled product (either (+) or (-)-1-[4-(-isopropoxyethoxymethyl)-phenoxy]-3- [11C]isopropylamino-2-propanol) was obtained in 99% radiochemical purity in 30 min with 15+/-5% (EOS, non-decay corrected) radiochemical yield and 3.5+/-1 Ci/micromol specific radioactivity. Preliminary biological evaluation of the tracer in rats showed that about 30% of heart uptake of [11C](S)-bisoprolol is due to specific binding. The high non-specific uptake in lung might mask the heart uptake, thus precluding the use of [11C](S)-bisoprolol for heart and lung studies by PET. The remarkably high uptake of the tracer in rat brain areas rich of beta-adrenergic receptors such as pituitary (1.8+/-0.3% I.D. at 30 min) was blocked by pre-treatment with the beta-adrenergic antagonists propranolol (45%) and bisoprolol (51%, p<0.05). [11C](S)-bisoprolol deserves further evaluation in other animal models as a putative beta(1) selective radioligand for in vivo investigation of central adrenoceptors.
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Visser TJ, van der Wouden EA, van Waarde A, Doze P, Elsinga PH, Vaalburg W. Synthesis and biodistribution of [11c]procaterol, a beta2-adrenoceptor agonist for positron emission tomography. Appl Radiat Isot 2000; 52:857-63. [PMID: 10800722 DOI: 10.1016/s0969-8043(99)00267-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The potent, subtype-selective radioligand (+/-)-erythro-5-(1-hydroxy-2-[11C]isopropyl-aminobutyl)-8-hydroxy-car bostyril ([11C]procaterol) was synthesized and evaluated for visualization of pulmonary beta2-adrenoceptors with positron emission tomography (PET). Procaterol was labelled by reductive alkylation of the desisopropyl precursor with [11C]acetone under the influence of NaCNBH3 and acetic acid. Synthesis and HPLC purification were performed in 34 min. Specific activities ranged from 26.5-39.3 TBq (about 700-1000 Ci)/mmol and the radiochemical yield was 2.4-8.6% (corrected for decay). Biodistribution studies were performed in male Wistar rats which were either untreated or predosed with (D,L)-propranolol hydrochloride (beta-adrenoceptor antagonist, 2.5 mg/kg), ICI 118551 (beta2-adrenoceptor antagonist, 0.15 mg/kg), CGP 20712A (beta1-adrenoceptor antagonist, 0.15 mg/kg) or isoprenaline (beta1-adrenoceptor agonist, 15 mg/kg). Specific binding was observed in lungs, spleen and red blood cells, tissues known to contain beta2-adrenoceptors. Pulmonary binding was blocked by propranolol, ICI 118551 and isoprenaline, but not by CGP 20712A. This binding pattern is consistent with the beta2 selectivity of the radioligand. The clearance of [11C]procaterol was biphasic, with a rapid distribution phase (t1/2 0.17 min) representing 90% of the injected dose followed by an elimination phase (t1/2 18.1 min). About 45% of the plasma radioactivity was unmetabolized procaterol at 15 min postinjection. In a dynamic PET-study, the lungs of untreated control rats could barely be detected and total/non-specific binding ratios rose to only 1.2 at 20 min postinjection. Although labelling and administration of (-) erythroprocaterol, the most active of 4 stereoisomers, may produce better results, [11C]procaterol seems unsuitable for beta-adrenoceptor imaging.
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Affiliation(s)
- T J Visser
- Positron Emission Tomography (PET) Center, Groningen University Hospital, The Netherlands
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48
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Pike VW, Law MP, Osman S, Davenport RJ, Rimoldi O, Giardinà D, Camici PG. Selection, design and evaluation of new radioligands for PET studies of cardiac adrenoceptors. PHARMACEUTICA ACTA HELVETIAE 2000; 74:191-200. [PMID: 10812957 DOI: 10.1016/s0031-6865(99)00032-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Changes in the numbers of human cardiac adrenoceptors (ARs) are associated with various diseases, such as myocardial ischemia, congestive heart failure, cardiomyopathy and hypertension. There is a clear need for capability to assess human cardiac ARs directly in vivo. Positron emission tomography (PET) is an imaging technique that provides this possibility, if effective radioligands can be developed for the targeted ARs. Here, the status of myocardial AR radioligand development for PET is described. Currently, there exist effective radioligands for imaging beta-ARs in human myocardium. One of these, [11C](S)-CGP 12177, is applied extensively to clinical research with PET, sometimes with other tracers of other aspects of the noradrenalin system. Alternative radioligands are in development for beta-ARs, including beta 1-selective radioligands. A promising radioligand for imaging myocardial alpha 1-ARs, [11C]GB67, is now being evaluated in human PET experiments.
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Affiliation(s)
- V W Pike
- MRC Cyclotron Unit, Imperial College School of Medicine, Hammersmith Hospital, London, UK.
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49
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van Waarde A, Elsinga PH, Doze P, Heldoorn M, Jaeggi KA, Vaalburg W. A novel beta-adrenoceptor ligand for positron emission tomography: evaluation in experimental animals. Eur J Pharmacol 1998; 343:289-96. [PMID: 9570478 DOI: 10.1016/s0014-2999(97)01528-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Myocardial and pulmonary beta-adrenoceptors can be imaged and quantified with the antagonist (S)-4-[3[(1,1-dimethylethyl)amino]-2-hydroxypropoxy]-1,3-dihydro-2H-b enzimidazol-2-[11C]-one (S-[11C]CGP-12177). The synthesis of this ligand (based on the reaction of a precursor with [11C]phosgene) is laborious and in many centers the final product has a low and variable specific activity. This prevents widespread use of S-[11C]CGP-12177 for studies in patients. We prepared S-[11C]CGP-12388, the isopropyl analogue of CGP-12177, by a reliable one-pot procedure and evaluated the radiopharmaceutical for beta-adrenoceptor imaging. Blocking experiments with subtype-selective beta-adrenergic drugs showed that myocardial and pulmonary uptake of S-[11C]CGP-12388 in anesthetized rats reflects ligand binding to beta1- and beta2-adrenoceptors. In this animal model, clearance, metabolism and tissue/plasma ratios of S-[11C]CGP-12388 were similar to those of S-[11C]CGP-12177. A [18F]fluoroisopropyl analogue of CGP-12177 showed less favorable characteristics. S-[11C]CGP-12388 was therefore selected for evaluation in humans and it may become the tracer of choice for clinical studies since it is easily prepared.
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Affiliation(s)
- A van Waarde
- Positron Emission Tomography Center, University Hospital, Groningen, The Netherlands
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