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O'Sullivan J, Colleran J, Twamley B, Heaney F. Highly Selective Fluorimetric Turn-Off Detection of Copper(II) by Two Different Mechanisms in Calix[4]arene-Based Chemosensors and Chemodosimeters. Chempluschem 2020; 84:1610-1622. [PMID: 31943920 DOI: 10.1002/cplu.201900448] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 09/09/2019] [Indexed: 01/01/2023]
Abstract
Isoxazolo-pyrene tethered calix[4]arenes selectively detect copper(II) ions without interference from related perchlorate ions. The fluorescence emission of the probes, synthesised by nitrile oxide alkyne cycloaddition, and characterised by spectroscopic and crystallographic data, is rapidly reduced by Cu(II) ions. Detection limits are in the micromolar or sub-micromolar range (0.3-3.6 μM) based on a 1 : 1 sensor:analyte interaction. Voltammetric behaviour and 1 H NMR data provide new insights into the sensing mechanism which is dependent on the calixarene substitution pattern. When the calixarene lower rim is fully substituted, Cu(II) detection occurs through a traditional chelation mechanism. In contrast, for calixarenes 1,3-disubstituted on the lower rim, detection takes place through a chemodosimetric redox reaction. The isolation of a calix[4]diquinone from the reaction with excess Cu(ClO4 )2 provides confirmation that the sensor-analyte interaction culminates in irreversible sensor oxidation.
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Affiliation(s)
- Justine O'Sullivan
- Department of Chemistry, Maynooth University, Maynooth, Co. Kildare, W23 F2H6, Ireland
| | - John Colleran
- School of Chemical & Pharmaceutical Sciences, and Applied Electrochemistry Group Focas Institute, Camden Row, Technical University Dublin, Kevin Street, Dublin 8, D08 NF82, Ireland
| | - Brendan Twamley
- School of Chemistry, Trinity College Dublin, University of Dublin, Dublin 2, Ireland
| | - Frances Heaney
- Department of Chemistry, Maynooth University, Maynooth, Co. Kildare, W23 F2H6, Ireland
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2
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Ishiki HM, Filho JMB, da Silva MS, Scotti MT, Scotti L. Computer-aided Drug Design Applied to Parkinson Targets. Curr Neuropharmacol 2018; 16:865-880. [PMID: 29189169 PMCID: PMC6080092 DOI: 10.2174/1570159x15666171128145423] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 11/24/2017] [Indexed: 12/01/2022] Open
Abstract
Background Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by debilitating motor deficits, as well as autonomic problems, cognitive declines, changes in affect and sleep disturbances. Although the scientific community has performed great efforts in the study of PD, and from the most diverse points of view, the disease remains incurable. The exact mechanism underlying its progression is unclear, but oxidative stress, mitochondrial dysfunction and inflammation are thought to play major roles in the etiology. Objective Current pharmacological therapies for the treatment of Parkinson’s disease are mostly inadequate, and new therapeutic agents are much needed. Methods In this review, recent advances in computer-aided drug design for the rational design of new compounds against Parkinson disease; using methods such as Quantitative Structure-Activity Relationships (QSAR), molecular docking, molecular dynamics and pharmacophore modeling are discussed. Results In this review, four targets were selected: the enzyme monoamine oxidase, dopamine agonists, acetylcholine receptors, and adenosine receptors. Conclusion Computer aided-drug design enables the creation of theoretical models that can be used in a large database to virtually screen for and identify novel candidate molecules.
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Affiliation(s)
- Hamilton M Ishiki
- University of Western Sao Paulo (Unoeste), Presidente Prudente, SP, Brazil
| | | | | | - Marcus T Scotti
- Federal University of Paraiba, Campus I, Joao Pessoa-PB, Brazil
| | - Luciana Scotti
- Federal University of Paraiba, Campus I, Joao Pessoa-PB, Brazil
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3
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Tomassoli I, Gündisch D. The twin drug approach for novel nicotinic acetylcholine receptor ligands. Bioorg Med Chem 2015; 23:4375-4389. [PMID: 26142318 PMCID: PMC4527756 DOI: 10.1016/j.bmc.2015.06.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/30/2015] [Accepted: 06/10/2015] [Indexed: 01/10/2023]
Abstract
The association of two pharmacophoric entities generates so-called 'twin drugs' or dimer derivatives. We applied this approach for the design of a small compound library for the interaction with α4β2(∗) nicotinic acetylcholine receptors (nAChRs). In this compound series, the nAChR ligand N,N-dimethyl-2-(pyridin-3-yloxy)ethan-1-amine 9 served as one pharmacological entity and it was initially kept constant as one part of the 'twin' compound. 'Twin' compounds with identical or non-identical entities using the 'no linker mode' or 'overlap' mode were synthesized and evaluated for their nAChR affinities. Compound 17a showed the highest affinity for the α4β2(∗) nAChR subtype (Ki=0.188 nM) and its (di)fluoro analogs could retain nanomolar affinities, when replacing pyridine as the hydrogen bond acceptor system by mono- or difluoro-phenyls. The 'twin drug' approach proved to provide compounds with high affinity and subtype selectivity for α4β2(∗) nAChRs.
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Affiliation(s)
- Isabelle Tomassoli
- Department of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo, Hilo, HI, USA
| | - Daniela Gündisch
- Department of Pharmaceutical Sciences, The Daniel K. Inouye College of Pharmacy, University of Hawai'i at Hilo, Hilo, HI, USA.
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4
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Computational studies of novel carbonyl-containing diazabicyclic ligands interacting with α4β2 nicotinic acetylcholine receptor (nAChR) reveal alternative binding modes. Bioorg Med Chem Lett 2013; 23:5105-13. [DOI: 10.1016/j.bmcl.2013.07.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 07/05/2013] [Accepted: 07/16/2013] [Indexed: 11/22/2022]
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5
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Xiao Y, Hammond PS, Mazurov AA, Yohannes D. Multiple Interaction Regions in the Orthosteric Ligand Binding Domain of the α7 Neuronal Nicotinic Acetylcholine Receptor. J Chem Inf Model 2012; 52:3064-73. [DOI: 10.1021/ci3001953] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yunde Xiao
- Targacept, Inc., 200 East
First Street, Suite 300, Winston-Salem, North Carolina 27101, United
States
| | - Philip S. Hammond
- Targacept, Inc., 200 East
First Street, Suite 300, Winston-Salem, North Carolina 27101, United
States
| | - Anatoly A. Mazurov
- Targacept, Inc., 200 East
First Street, Suite 300, Winston-Salem, North Carolina 27101, United
States
| | - Daniel Yohannes
- Targacept, Inc., 200 East
First Street, Suite 300, Winston-Salem, North Carolina 27101, United
States
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Mazurov AA, Miao L, Bhatti BS, Strachan JP, Akireddy S, Murthy S, Kombo D, Xiao YD, Hammond P, Zhang J, Hauser TA, Jordan KG, Miller CH, Speake JD, Gatto GJ, Yohannes D. Discovery of 3-(5-chloro-2-furoyl)-3,7-diazabicyclo[3.3.0]octane (TC-6683, AZD1446), a novel highly selective α4β2 nicotinic acetylcholine receptor agonist for the treatment of cognitive disorders. J Med Chem 2012; 55:9181-94. [PMID: 22793665 DOI: 10.1021/jm3006542] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Diversification of essential nicotinic cholinergic pharmacophoric elements, i.e., cationic center and hydrogen bond acceptor, resulted in the discovery of novel potent α4β2 nAChR selective agonists comprising a series of N-acyldiazabicycles. Core characteristics of the series are an exocyclic carbonyl moiety as a hydrogen bond acceptor and endocyclic secondary amino group. These features are positioned at optimal distance and with optimal relative spatial orientation to provide near optimal interactions with the receptor. A novel potent and highly selective α4β2 nAChR agonist 3-(5-chloro-2-furoyl)-3,7-diazabicyclo[3.3.0]octane (56, TC-6683, AZD1446) with favorable pharmaceutical properties and in vivo efficacy in animal models has been identified as a potential treatment for cognitive deficits associated with psychiatric or neurological conditions and is currently being progressed to phase 2 clinical trials as a treatment for Alzheimer's disease.
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Affiliation(s)
- Anatoly A Mazurov
- Targacept, Inc., Winston Salem, North Carolina 27101, United States.
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7
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Yu LF, Tückmantel W, Eaton JB, Caldarone B, Fedolak A, Hanania T, Brunner D, Lukas RJ, Kozikowski AP. Identification of novel α4β2-nicotinic acetylcholine receptor (nAChR) agonists based on an isoxazole ether scaffold that demonstrate antidepressant-like activity. J Med Chem 2012; 55:812-23. [PMID: 22148173 DOI: 10.1021/jm201301h] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
There is considerable evidence to support the hypothesis that the blockade of nAChR is responsible for the antidepressant action of nicotinic ligands. The nicotinic acetylcholine receptor (nAChR) antagonist, mecamylamine, has been shown to be an effective add-on in patients that do not respond to selective serotonin reuptake inhibitors. This suggests that nAChR ligands may address an unmet clinical need by providing relief from depressive symptoms in refractory patients. In this study, a new series of nAChR ligands based on an isoxazole-ether scaffold have been designed and synthesized for binding and functional assays. Preliminary structure-activity relationship (SAR) efforts identified a lead compound 43, which possesses potent antidepressant-like activity (1 mg/kg, IP; 5 mg/kg, PO) in the classical mouse forced swim test. Early stage absorption, distribution, metabolism, excretion, and toxicity (ADME-Tox) studies also suggested favorable drug-like properties, and broad screening toward other common neurotransmitter receptors indicated that compound 43 is highly selective for nAChRs over the other 45 neurotransmitter receptors and transporters tested.
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Affiliation(s)
- Li-Fang Yu
- Drug Discovery Program, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612, United States
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8
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Computational analysis of the binding ability of heterocyclic and conformationally constrained epibatidine analogs in the neuronal nicotinic acetylcholine receptor. Mol Divers 2009; 14:201-11. [DOI: 10.1007/s11030-009-9161-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Accepted: 05/09/2009] [Indexed: 11/26/2022]
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9
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10
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Convenient synthesis of isoxazolines via tandem isomerization of allyl compounds to vinylic derivatives and 1,3-dipolar cycloaddition of nitrile oxides to the vinylic compounds. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.07.176] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Carroll FI, Robinson TP, Brieaddy LE, Atkinson RN, Mascarella SW, Damaj MI, Martin BR, Navarro HA. Synthesis and Nicotinic Acetylcholine Receptor Binding Properties of Bridged and Fused Ring Analogues of Epibatidine. J Med Chem 2007; 50:6383-91. [DOI: 10.1021/jm0704696] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- F. Ivy Carroll
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, and Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - T. Philip Robinson
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, and Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Lawrence E. Brieaddy
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, and Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Robert N. Atkinson
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, and Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - S. Wayne Mascarella
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, and Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - M. Imad Damaj
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, and Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Billy R. Martin
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, and Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298
| | - Hernán A. Navarro
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, and Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298
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12
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Vargas-Sanchez M, Lakhdar S, Couty F, Evano G. Reaction of azetidines with chloroformates. Org Lett 2007; 8:5501-4. [PMID: 17107057 DOI: 10.1021/ol062128c] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of an azetidine with a chloroformate can give either the dealkylated heterocycle or the ring-opened product (gamma-chloroamine), which can further cyclize to the oxazinanone. A general study of this underrated reaction was conducted and revealed that azetidines can undergo smooth nucleophilic ring-opening reactions to highly functionalized gamma-chloroamines in the presence of a variety of alkyl chloroformates under mild reaction conditions. Yields are usually good, and parameters governing this reaction were evaluated. [reaction: see text].
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Affiliation(s)
- Monica Vargas-Sanchez
- Institut Lavoisier de Versailles, UMR CNRS 8180, Université de Versailles Saint Quentin en Yvelines, 45 avenue des Etats-Unis, 78035 Versailles Cedex, France
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13
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Romanelli MN, Gratteri P, Guandalini L, Martini E, Bonaccini C, Gualtieri F. Central Nicotinic Receptors: Structure, Function, Ligands, and Therapeutic Potential. ChemMedChem 2007; 2:746-67. [PMID: 17295372 DOI: 10.1002/cmdc.200600207] [Citation(s) in RCA: 145] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The growing interest in nicotinic receptors, because of their wide expression in neuronal and non-neuronal tissues and their involvement in several important CNS pathologies, has stimulated the synthesis of a high number of ligands able to modulate their function. These membrane proteins appear to be highly heterogeneous, and still only incomplete information is available on their structure, subunit composition, and stoichiometry. This is due to the lack of selective ligands to study the role of nAChR under physiological or pathological conditions; so far, only compounds showing selectivity between alpha4beta2 and alpha7 receptors have been obtained. The nicotinic receptor ligands have been designed starting from lead compounds from natural sources such as nicotine, cytisine, or epibatidine, and, more recently, through the high-throughput screening of chemical libraries. This review focuses on the structure of the new agonists, antagonists, and allosteric ligands of nicotinic receptors, it highlights the current knowledge on the binding site models as a molecular modeling approach to design new compounds, and it discusses the nAChR modulators which have entered clinical trials.
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Affiliation(s)
- M Novella Romanelli
- Laboratory of Design, Synthesis, and Study of Biologically Active Heterocycles (HeteroBioLab), Department of Pharmaceutical Sciences, University of Florence, via Ugo Schiff 6, 50019 Sesto Fiorentino, Italy.
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14
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Ma SH, Yoon DH, Ha HJ, Lee WK. Preparation of enantiopure 2-acylazetidines and their reactions with chloroformates. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2006.11.033] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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15
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Yogeeswari P, Sriram D, Ratan Bal T, Thirumurugan R. Epibatidine and its analogues as nicotinic acetylcholine receptor agonist: an update. Nat Prod Res 2006; 20:497-505. [PMID: 16644549 DOI: 10.1080/14786410600604583] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Epibatidine (EPB) (1), an alkaloid isolated from the skin of the Ecuadorian poison frog, Epipedobates tricolor has attracted attention because of its exceptionally powerful analgesic properties: several hundred times greater than those of morphine, and the fact that it acts at nicotine rather than opiate receptors. Although the substance is toxic, it does serve as a lead compound in the development of drugs for pain relief as well as treatment of disorders whose pathogenesis involves nicotinic receptors. In this article, isolation, synthetic methods, effect on neuronal and neuromuscular nicotinic receptors, therapeutic potential, toxicity, nicotinic pharmacophore structural modifications related issues of 1 are discussed.
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Affiliation(s)
- Perumal Yogeeswari
- Medicinal Chemistry Research Laboratory, Pharmacy group, Birla Institute of Technology and Science, Pilani 333 031, India.
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16
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The Chemistry and Pharmacology of Anatoxin-a and Related Homotropanes with respect to Nicotinic Acetylcholine Receptors. Mar Drugs 2006. [DOI: 10.3390/md403228] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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17
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Paul Singh Ishar M, Singh G, Elango M, Subramaniam V. Regio- and Exo-p-Facial Selective 1,3-Dipolar Cycloaddition of a-(3-Pyridyl)-N-phenylnitrone to Norbornadiene: Activation of a p-Bond of Norbornadiene and Control of Regiochemistry of Nitrone Cycloaddition by Nitrone Addition to the Other Double Bond. HETEROCYCLES 2006. [DOI: 10.3987/com-06-10732] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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18
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Dukat M, Ramunno A, Banzi R, Damaj MI, Martin B, Glennon RA. 3-(2-Aminoethyl)pyridine analogs as α4β2 nicotinic cholinergic receptor ligands. Bioorg Med Chem Lett 2005; 15:4308-12. [PMID: 16039854 DOI: 10.1016/j.bmcl.2005.06.053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Revised: 06/16/2005] [Accepted: 06/16/2005] [Indexed: 11/23/2022]
Abstract
An examination of several 3-(2-aminoethyl)pyridine analogs suggests that they likely orient at alpha4beta2 nicotinic cholinergic receptors in a different fashion than their correspondingly substituted nicotine analogs.
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Affiliation(s)
- Małgorzata Dukat
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298-0540, USA
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19
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Singh G, Ishar MPS, Girdhar NK, Singh L. Investigations on regio- and stereoselectivities in cycloadditions involving α- (3-pyridyl)-N-phenylnitrone: Development of an efficient route to novel nicotine analogs. J Heterocycl Chem 2005. [DOI: 10.1002/jhet.5570420603] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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20
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Kanne DB, Tomizawa M, Durkin KA, Casida JE. 6'-Methylpyrido[3,4-b]norhomotropane: synthesis and outstanding potency in relation to the alpha4beta2 nicotinic receptor pharmacophore model. Bioorg Med Chem Lett 2005; 15:877-81. [PMID: 15686879 DOI: 10.1016/j.bmcl.2004.12.069] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2004] [Revised: 12/21/2004] [Accepted: 12/22/2004] [Indexed: 10/25/2022]
Abstract
6'-Methylpyrido[3,4-b]norhomotropane [synthesis as the racemate reported here] is more potent at the alpha4beta2 nicotinic receptor than any previous bridged nicotinoid. The two nitrogens and 6'-methyl substituent are superimposable on the two nitrogens and 6-chloro substituent of epibatidine, with the best fit on comparing the chair conformer of the (1R)-pyridonorhomotropane with natural (1R)-epibatidine. In this pharmacophore model, the 6'-methyl substituent may be equivalent to the acetyl methyl of acetylcholine.
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Affiliation(s)
- David B Kanne
- Environmental Chemistry and Toxicology Laboratory, Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720-3112, USA
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21
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Daly JW. Nicotinic Agonists, Antagonists, and Modulators From Natural Sources. Cell Mol Neurobiol 2005; 25:513-52. [PMID: 16075378 DOI: 10.1007/s10571-005-3968-4] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2004] [Accepted: 04/14/2004] [Indexed: 10/25/2022]
Abstract
1. Acetylcholine receptors were initially defined as nicotinic or muscarinic, based on selective activation by two natural products, nicotine and muscarine. Several further nicotinic agonists have been discovered from natural sources, including cytisine, anatoxin, ferruginine, anabaseine, epibatidine, and epiquinamide. These have provided lead structures for the design of a wide range of synthetic agents. 2. Natural sources have also provided competitive nicotinic antagonists, such as the Erythrina alkaloids, the tubocurarines, and methyllycaconitine. Noncompetitive antagonists, such as the histrionicotoxins, various izidines, decahydroquinolines, spiropyrrolizidine oximes, pseudophrynamines, ibogaine, strychnine, cocaine, and sparteine have come from natural sources. Finally, galanthamine, codeine, and ivermectin represent positive modulators of nicotinic function, derived from natural sources. 3. Clearly, research on acetylcholine receptors and functions has been dependent on key natural products and the synthetic agents that they inspired.
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Affiliation(s)
- John W Daly
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, DHHS, Bethesda, Maryland 20892, USA.
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23
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Carroll FI. Epibatidine structure–activity relationships. Bioorg Med Chem Lett 2004; 14:1889-96. [PMID: 15050621 DOI: 10.1016/j.bmcl.2004.02.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2003] [Revised: 02/03/2004] [Accepted: 02/03/2004] [Indexed: 10/26/2022]
Abstract
Epibatidine is a potent but nonselective nAChR agonist. Its biological effects appear to be mediated largely by alpha4beta2 nAChRs. Surprisingly, only a limited number of epibatidine analogues have been synthesized and evaluated in in vitro assays. Even fewer analogues have received in vivo pharmacological evaluation. In this paper, SAR studies directed toward epibatidine analogues will be reviewed.
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Affiliation(s)
- F Ivy Carroll
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, NC 27709, USA.
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24
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Abstract
Progress towards the development of alpha4beta2 nicotinic acetylcholinergic receptor pharmacophores is reviewed from the early Beers and Riech model to the newer vector models.
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Affiliation(s)
- Richard A Glennon
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA.
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Glennon RA. 2. Medicinal chemistry of alpha4beta2 nicotinic cholinergic receptor ligands. PROGRESS IN MEDICINAL CHEMISTRY 2004; 42:55-123. [PMID: 15003719 DOI: 10.1016/s0079-6468(04)42002-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Affiliation(s)
- Richard A Glennon
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Box 581 MCV Station, Richmond, VA 23298, USA
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26
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Dogruer D, Lee M, Dukat M, Damaj MI, Martin BR, Glennon RA. 3-(4-Aminobutyn-1-yl)pyridines: binding at α4β2 nicotinic cholinergic receptors. Bioorg Med Chem Lett 2004; 14:523-6. [PMID: 14698195 DOI: 10.1016/j.bmcl.2003.10.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The binding of a series pyridylbutynylamines 6 was examined at alpha4beta2 nACh receptors. Structural modifications, comparing 6 with pyridyl ethers 2, did not consistently result in parallel effects on receptor affinity, suggesting possible differences in their modes of binding. Furthermore, the binding of amine 6a seemed to be accounted for by the newer vector pharmacophore models.
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Affiliation(s)
- Deniz Dogruer
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, VA 23298-0540, Richmond, USA
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27
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Romanelli MN, Gualtieri F. Cholinergic nicotinic receptors: competitive ligands, allosteric modulators, and their potential applications. Med Res Rev 2003; 23:393-426. [PMID: 12710018 DOI: 10.1002/med.10037] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Discovery of the important role played by nicotinic acetylcholine receptors (nAChRs) in several CNS disorders has called attention to these membrane proteins and to ligands able to modulate their functions. The existence of different subtypes at multiple levels has complicated the understanding of this receptor's physiological role, but at the same time has increased the efforts to discover selective compounds in order to improve the pharmacological characterization of this kind of receptor and to make the possible therapeutical use of its modulators safer. This review focuses on the structure of new ligands for nAChRs, agonists, antagonists and allosteric modulators, and on their possible applications.
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Affiliation(s)
- M Novella Romanelli
- Dipartimento di Scienze Farmaceutiche, Università di Firenze, via Gino Capponi 9, 50121 Firenze, Italy.
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28
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Abstract
Epibatidine is a natural product that was isolated and identified by Daly and coworkers in 1992. Since that time, it has had a profound influence on the investigation of alpha4beta2 nicotinic cholinergic (nACh) receptor pharmacophore models, and has inspired the development of novel agents with therapeutic potential in CNS disorders. Apart from acetylcholine and nicotine, probably no other agent has had as much recent impact on nACh research as has epibatidine.
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Affiliation(s)
- Małgorzata Dukat
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, USA
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29
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Wei ZL, Petukhov PA, Xiao Y, Tückmantel W, George C, Kellar KJ, Kozikowski AP. Synthesis, nicotinic acetylcholine receptor binding affinities, and molecular modeling of constrained epibatidine analogues. J Med Chem 2003; 46:921-4. [PMID: 12620069 DOI: 10.1021/jm025613w] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Conformationally constrained epibatidine analogues 20a,b and 23a,b were synthesized using a radical cyclization as the key step. Radioligand displacement assays to six defined rat nicotinic acetylcholine receptor (nAChR) subtypes showed that 20a,b bind with moderate affinities, while 23a,b have low affinities. 20a exhibits higher affinity for the beta2 containing subtype than for the beta4 containing counterpart, while 20b possesses reversed selectivity. Modeling studies suggest that the spatial distribution of the ligand's atoms around the pharmacophore elements may control their nAChR subtype selectivity.
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Affiliation(s)
- Zhi-Liang Wei
- Drug Discovery Program, Department of Neurology, Georgetown University Medical Center, 3900 Reservoir Road, NW, Washington, DC 20057, USA
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30
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Ferretti G, Dukat M, Giannella M, Piergentili A, Pigini M, Quaglia W, Damaj MI, Martin BR, Glennon RA. Binding of nicotine and homoazanicotine analogues at neuronal nicotinic acetylcholinergic (nACh) receptors. Bioorg Med Chem Lett 2003; 13:733-5. [PMID: 12639569 DOI: 10.1016/s0960-894x(02)01031-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A total of 20 substituted analogues of nicotine (1a) and homoazanicotine (3a) were examined in order to determine whether or not they might bind in a similar manner at alpha4beta2 nicotinic acetylcholinergic (nACh) receptors. It was found that parallel structural changes in the two series resulted in parallel shifts in affinity. Evidence suggests that the two series are binding in a comparable fashion.
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Affiliation(s)
- G Ferretti
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298, USA
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31
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Beene DL, Brandt GS, Zhong W, Zacharias NM, Lester HA, Dougherty DA. Cation-pi interactions in ligand recognition by serotonergic (5-HT3A) and nicotinic acetylcholine receptors: the anomalous binding properties of nicotine. Biochemistry 2002; 41:10262-9. [PMID: 12162741 DOI: 10.1021/bi020266d] [Citation(s) in RCA: 233] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of tryptophan analogues has been introduced into the binding site regions of two ion channels, the ligand-gated nicotinic acetylcholine and serotonin 5-HT(3A) receptors, using unnatural amino acid mutagenesis and heterologous expression in Xenopus oocytes. A cation-pi interaction between serotonin and Trp183 of the serotonin channel 5-HT(3A)R is identified for the first time, precisely locating the ligand-binding site of this receptor. The energetic contribution of the observed cation-pi interaction between a tryptophan and the primary ammonium ion of serotonin is estimated to be approximately 4 kcal/mol, while the comparable interaction with the quaternary ammonium of acetylcholine is approximately 2 kcal/mol. The binding mode of nicotine to the nicotinic receptor of mouse muscle is examined by the same technique and found to differ significantly from that of the natural agonist, acetylcholine.
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Affiliation(s)
- Darren L Beene
- Divisions of Chemistry and Chemical Engineering and Biology, California Institute of Technology, Pasadena, California 91125, USA
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32
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Lee M, Dukat M, Liao L, Flammia D, Damaj MI, Martin B, Glennon RA. A comparison of the binding of three series of nicotinic ligands. Bioorg Med Chem Lett 2002; 12:1989-92. [PMID: 12113825 DOI: 10.1016/s0960-894x(02)00298-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A total of 24 aryl-substituted analogues of nicotine (1a) and two related series of nicotinic ligands, aminomethylpyridines 3 and ether analogues 8, were examined to determine if they bind at alpha4beta2 nACh receptors in a common manner. A modest correlation (r=0.785) was found between the affinities of the nicotine analogues and derivatives of 3, but little correlation (r=0.348) was found with analogues 8. However, a modest correlation (r=0.742) exists between the binding of analogues 3 and 8. It seems that 1-series and 8-series compounds bind differently but that the 3-series compounds share some intermediate binding similarity with both.
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Affiliation(s)
- Mase Lee
- Department of Medicinal Chemistry, School of Pharmacy, Box 980540, Virginia Commonwealth University, Richmond 23298, USA
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33
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Sharples CGV, Karig G, Simpson GL, Spencer JA, Wright E, Millar NS, Wonnacott S, Gallagher T. Synthesis and pharmacological characterization of novel analogues of the nicotinic acetylcholine receptor agonist (+/-)-UB-165. J Med Chem 2002; 45:3235-45. [PMID: 12109907 DOI: 10.1021/jm020814l] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
(+/-)-UB-165 (1) is a potent neuronal nicotinic acetylcholine receptor (nAChR) ligand, which displays functional selectivity between nAChR subtypes. Using UB-165 as a lead structure, two classes of racemic ligands were synthesized and assessed in binding assays for three major nAChR subtypes (alpha4beta2, alpha3beta4, and alpha7). The first class of compounds comprises the three pyridine isomers 4-6, corresponding to the 3-, 2-, and 4-substituted pyridine isomers, respectively. Deschloro UB-165 (4) displayed a 2-3-fold decrease in affinity at alpha4beta2 and alpha3beta4 nAChR subtypes, as compared with (+/-)-UB-165, while at the alpha7 subtype a 31-fold increase in affinity was observed. At each of the nAChR subtypes, high affinity binding was dependent on the presence of a 3-substituted pyridine, and the other isomers, 5 and 6, resulted in marked decreases in binding affinities. The second class of compounds is based on replacing the pyridyl unit of 1 with a diazine moiety, giving pyridazine (7), pyrimidine (8), and pyrazine (9), which retain the "3-pyridyl" substructure. Modest reductions in binding affinity were observed for all of the diazine ligands at all nAChR subtypes, with the exception of 7, which retained potency comparable to that of 4 in binding to alpha7 nAChR. In functional assays at the alpha3beta4 nAChR, all analogues 4-9 were less potent, as compared with 1, and the rank order of functional potencies correlated with that of binding potencies. Computational studies indicate that the 3-substituted pyridine 4 and 2-substituted pyridine 5, as well as the diazine analogues 7-9, all conform to a distance-based pharmacophore model recently proposed for the alpha4beta2 receptor. However, the nicotinic potencies of these ligands vary considerably and because 5 lacks appreciable nicotinic activity, it is clear that further refinements of this model are necessary in order to describe adequately the structural and electronic demands associated with this nAChR subtype. This rational series of compounds based on UB-165 presents a systematic approach to defining subtype specific pharmacophores.
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34
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Brown LL, Kulkarni S, Pavlova OA, Koren AO, Mukhin AG, Newman AH, Horti AG. Synthesis and evaluation of a novel series of 2-chloro-5-((1-methyl-2-(S)-pyrrolidinyl)methoxy)-3-(2-(4-pyridinyl)vinyl)pyridine analogues as potential positron emission tomography imaging agents for nicotinic acetylcholine receptors. J Med Chem 2002; 45:2841-9. [PMID: 12061886 DOI: 10.1021/jm010550n] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reportedly, 2-[(18)F]fluoro-A-85380, 1, a promising radiotracer for imaging the nicotinic acetylcholine receptor (nAChR) by positron emission tomography (PET) in humans, exhibits slow penetration through the blood-brain barrier (BBB) due to its low lipophilicity. A ligand for nAChRs with greater lipophilicity than that of 1 would be potentially more favorable for PET imaging of nAChR due to its faster penetration through the BBB. Herein, a novel series of compounds has been developed based on the high affinity ligand for nAChRs, 2-chloro-5-((1-methyl-2-(S)-pyrrolidinyl)methoxy)-3-(2-(4-pyridinyl)vinyl)pyridine, 3b. The in vitro binding affinities for the new series were found to be in the range of K(i) = 9-331 pM. A molecular modeling study showed differences in the comformational profiles and the electronic properties of these compounds, which provides further insight into the structure-activity relationships at nAChR. Lipophilicities of the compounds 3b-6b have been found to be substantially higher than that of 1. As a result, compounds 3b-6b might exhibit a faster penetration through the BBB than the less lipophilic 1. The N-methyl derivatives 3b and 6b demonstrated very high affinities at nAChRs (K(i) = 28 and 23 pM, respectively) and will be targets for development of (11)CH(3)-labeled derivatives as radiotracers for PET imaging of nAChRs.
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Affiliation(s)
- LaVerne L Brown
- Neuroimaging Research Branch and Medicinal Chemistry Section, Intramural Research Program, National Institute on Drug Abuse, 5500 Nathan Shock Drive, Baltimore, MD 21224, USA
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35
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Avenoza A, Busto JH, Cativiela C, Dordal A, Frigola J, Peregrina JM. Synthesis, activity and theoretical study of ABT-418 analogues. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)00388-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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36
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Gündisch D, Kämpchen T, Schwarz S, Seitz G, Siegl J, Wegge T. Syntheses and evaluation of pyridazine and pyrimidine containing bioisosteres of (+/-)-pyrido[3.4-b]homotropane and pyrido-[3.4-b]tropane as novel nAChR ligands. Bioorg Med Chem 2002; 10:1-9. [PMID: 11738601 DOI: 10.1016/s0968-0896(01)00258-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Bioisosteric replacement of the pyridine pharmacophoric element in (+/-)-pyrido[3.4-b]homotropane (PHT) and pyrido[3.4-b]tropane with the pyridazine and pyrimidine nucleus resulted in hitherto unknown nAChR ligands such as 5-8. Inverse type Diels-Alder reactions constitute the key steps in the new routes to the pyridazine- or pyrimidine-annulated bioisosteres. The enantiopure (+)-2-tropinone (11) from the 'chiral pool' is transformed to the ring-expanded silyl enol ether 12 and to the enamine 15. Both proved to be highly dienophilic species in the inverse type [4+2] cycloaddition reactions with the 1,2,4,5-tetrazines 13 and 16a,b or with the 1,3,5-triazine 19 to provide the enantiopure target compounds 5-7. In the same way the racemic pyrimidine-annulated species 8 was obtained from 3-tropanone 21. The new ligands were tested for their in vitro affinity for (alpha4)2(beta2)3 and alpha7* nAChR subtype. In comparison to PHT, well known to exhibit affinity for agonist binding sites in rat brain approximately equivalent to that of (+)-anatoxin-a (1), replacement of the pyridine by the bioisosteric pyridazine resulted in 30-fold lower affinity at the (alpha4)2(beta2)3 subtype. The annulated diazinotropanes 6-8, ligands with ferruginine-like structures more or less retained the affinity of (-)-norferruginine (3) except of compound 7. Remarkably, all of the novel ligands are devoid of affinity at the alpha7* subtype.
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Affiliation(s)
- Daniela Gündisch
- Department of Pharmaceutical Chemistry, Rhein.Friedr.Wilh. University, Kreuzbergweg 26, D-53115, Bonn, Germany
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37
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Tønder JE, Olesen PH, Hansen JB, Begtrup M, Pettersson I. An improved nicotinic pharmacophore and a stereoselective CoMFA-model for nicotinic agonists acting at the central nicotinic acetylcholine receptors labelled by. J Comput Aided Mol Des 2001; 15:247-58. [PMID: 11289078 DOI: 10.1023/a:1008140021426] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A study of a series of compounds with agonistic effect at the alpha4beta2 nicotinic acetylcholine receptors resulted in an improved pharmacophore model as well as a CoMFA model. The pharmacophore was composed of three pharmacophoric elements: (1) a site point (a) corresponding to a protonated nitrogen atom, (2) a site point (b) corresponding to an electronegative atom capable of forming a hydrogen bond, and (3) the centre of a heteroaromatic ring or a C=O bond (c). The pharmacophoric elements were related by the following parameters: (a-b) 7.3-8.0 A, (a-c) 6.5-7.4 A, and the angle between the two distance vectors (delta bac) 30.4-35.8 degrees. In addition to this, a stereoselective CoMFA model was developed, which showed good predictability even for compound classes not present in the training set.
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Affiliation(s)
- J E Tønder
- Health Care Discovery, Novo Nordisk A/S, Måløv, Denmark
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38
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Nielsen SF, Nielsen EO, Olsen GM, Liljefors T, Peters D. Novel potent ligands for the central nicotinic acetylcholine receptor: synthesis, receptor binding, and 3D-QSAR analysis. J Med Chem 2000; 43:2217-26. [PMID: 10841800 DOI: 10.1021/jm990973d] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the past few years the focus on central acetylcholine receptors has shifted from compounds with affinity for muscarinic acetylcholine receptors (mAChR) to compounds with affinity for nicotinic acetylcholine receptors (nAChR). The therapeutic potential includes treatment of a variety of diseases, e.g., Alzheimer's disease, Parkinson's disease, and Tourette's syndrome. This work describes the synthesis of six novel series of potent ligands with nanomolar affinity for the alpha4beta2 nAChR subtype. Structure-activity relationship (SAR) was evaluated by the calculation of a 3D-QSAR model. 3D-QSAR analysis of the compounds using the GRID/GOLPE methodology resulted in a model of high quality (R(2) = 0.97, Q(2) = 0.81). The coefficient plots reveal that the steric interactions between the target and our compounds are of major importance for the affinity. Bulky substituents in the 6-position of the pyridine ring will reduce the affinity of the compounds, whereas bulky ring systems including a sp(3)-nitrogen will increase the affinity of the compounds.
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Affiliation(s)
- S F Nielsen
- NeuroSearch A/S, 93 Pederstrupvej, DK-2750 Ballerup, Denmark
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39
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Olesen PH, Tønder JE, Hansen JB, Hansen HC, Rimvall K. Bioisosteric replacement strategy for the synthesis of 1-azacyclic compounds with high affinity for the central nicotinic cholinergic receptors. Bioorg Med Chem 2000; 8:1443-50. [PMID: 10896121 DOI: 10.1016/s0968-0896(00)00063-8] [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: 11/28/2022]
Abstract
Bioisosteric replacement of the isoxazole heterocycle in (3-methyl-5-isoxazolyl)methylene-azacyclic compounds with pyridine, oxadiazole, or an acyl group resulted in ligands with high to moderate affinity for the central nicotinic cholinergic receptors (IC50 = 2.0 to IC50 > 1000 nM) labeled by [3H]methylcarbamylcholine. Additionally, further support of an important distance parameter for high-affinity nicotinic compounds has been provided.
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Affiliation(s)
- P H Olesen
- Health Care Discovery, Novo Nordisk A/S, Målov, Denmark.
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40
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Tønder JE, Begtrup M, Bondo Hansen J, Olesen PH. Exploring the Stereoselectivity in the Peterson Reaction of Several 2-Substituted 1-Azabicyclo[2.2.2]octan-3-ones. Tetrahedron 2000. [DOI: 10.1016/s0040-4020(00)00015-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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