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Zheng Y, Chen Y, He Y, Rizzo A, Zhou Y, Low KH, Krenske EH, Chiu P. Dearomative Intramolecular (4+3) Cycloadditions of Thiophenes. Angew Chem Int Ed Engl 2024; 63:e202407059. [PMID: 38758985 DOI: 10.1002/anie.202407059] [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: 04/14/2024] [Revised: 05/16/2024] [Accepted: 05/17/2024] [Indexed: 05/19/2024]
Abstract
Unexpectedly facile dearomative intramolecular (4+3) cycloadditions of thiophenes with epoxy enolsilanes, providing sulfur-bridged cycloadducts, are reported. A total of fifteen thiophene substrates have been found to undergo (4+3) cycloaddition smoothly to produce endo and exo (4+3) adducts in yields of up to 83 % with moderate to good diastereoselectivity. Complete conservation of enantiomeric purity was observed when the optically enriched epoxide was used. The desulfurizing transformations of the sulfur-bridged skeleton of the cycloadducts provide functionalized 6,7-fused bicyclic frameworks consisting of 1,3-cycloheptadiene subunits. Density functional theory calculations reveal the origins of the facile dearomatization of thiophenes in these (4+3) cycloadditions.
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Affiliation(s)
- Yufen Zheng
- Department of Chemistry, and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Yueyao Chen
- Laboratory for Synthetic Chemistry and Chemical Biology Limited, Science Park, Shatin, Hong Kong
| | - Yuxuan He
- Department of Chemistry, and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Antonio Rizzo
- Department of Chemistry, and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Yuchen Zhou
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Kam-Hung Low
- Department of Chemistry, and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Elizabeth H Krenske
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Pauline Chiu
- Department of Chemistry, and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong
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Singh K, Kumar P, Bhatia R, Mehta V, Kumar B, Akhtar MJ. Nipecotic acid as potential lead molecule for the development of GABA uptake inhibitors; structural insights and design strategies. Eur J Med Chem 2022; 234:114269. [DOI: 10.1016/j.ejmech.2022.114269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 03/05/2022] [Accepted: 03/05/2022] [Indexed: 11/04/2022]
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An overview of structurally diversified anticonvulsant agents. ACTA PHARMACEUTICA (ZAGREB, CROATIA) 2019; 69:321-344. [PMID: 31259739 DOI: 10.2478/acph-2019-0023] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/15/2018] [Indexed: 01/19/2023]
Abstract
There are several limited approaches to treat epilepsy in hospitals, for example, using medicines, surgery, electrical stimulation and dietary interventions. Despite the availability of all these new and old approaches, seizure is particularly difficult to manage. The quest for new antiepileptic molecules with more specificity and less CNS toxicity continues for medicinal chemists until a new and ideal drug arrives. This review covers new antiseizure molecules of different chemical classes, the exact mode of action of which is still unidentified. Newer agents include sulfonamides, thiadiazoles, semi- and thiosemicarbazones, pyrrolidine-2,5-diones, imidazoles, benzothiazoles and amino acid deriva tives. These new chemical entities can be useful for the design and development of forthcoming antiseizure agents.
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Zafar S, Jabeen I. GRID-independent molecular descriptor analysis and molecular docking studies to mimic the binding hypothesis of γ-aminobutyric acid transporter 1 (GAT1) inhibitors. PeerJ 2019; 7:e6283. [PMID: 30723616 PMCID: PMC6360079 DOI: 10.7717/peerj.6283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 12/14/2018] [Indexed: 12/13/2022] Open
Abstract
Background The γ-aminobutyric acid (GABA) transporter GAT1 is involved in GABA transport across the biological membrane in and out of the synaptic cleft. The efficiency of this Na+ coupled GABA transport is regulated by an electrochemical gradient, which is directed inward under normal conditions. However, in certain pathophysiological situations, including strong depolarization or an imbalance in ion homeostasis, the GABA influx into the cytoplasm is increased by re-uptake transport mechanism. This mechanism may lead to extra removal of extracellular GABA which results in numerous neurological disorders such as epilepsy. Thus, small molecule inhibitors of GABA re-uptake may enhance GABA activity at the synaptic clefts. Methods In the present study, various GRID-independent molecular descriptor (GRIND) models have been developed to shed light on the 3D structural features of human GAT1 (hGAT1) inhibitors using nipecotic acid and N-diarylalkenyl piperidine analogs. Further, a binding hypothesis has been developed for the selected GAT1 antagonists by molecular docking inside the binding cavity of hGAT1 homology model. Results Our results indicate that two hydrogen bond acceptors, one hydrogen bond donor and one hydrophobic region at certain distances from each other play an important role in achieving high inhibitory potency against hGAT1. Our docking results elucidate the importance of the COOH group in hGAT1 antagonists by considering substitution of the COOH group with an isoxazol ring in compound 37, which subsequently leads to a three order of magnitude decrease in biological activity of 37 (IC50 = 38 µM) as compared to compound 1 (IC50 = 0.040 µM). Discussion Our docking results are strengthened by the structure activity relationship of the data series as well as by GRIND models, thus providing a significant structural basis for understanding the binding of antagonists, which may be useful for guiding the design of hGAT1 inhibitors.
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Affiliation(s)
- Sadia Zafar
- Research Center for Modeling and Simulation (RCMS), National University of Sciences and Technology (NUST), Islamabad, Federal, Pakistan
| | - Ishrat Jabeen
- Research Center for Modeling and Simulation (RCMS), National University of Sciences and Technology (NUST), Islamabad, Federal, Pakistan
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Sowa AR, Brooks AF, Shao X, Henderson BD, Sherman P, Arteaga J, Stauff J, Lee AC, Koeppe RA, Scott PJH, Kilbourn MR. Development of Positron Emission Tomography Radiotracers for the GABA Transporter 1. ACS Chem Neurosci 2018; 9:2767-2773. [PMID: 29763549 DOI: 10.1021/acschemneuro.8b00183] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In vivo positron emission tomography (PET) imaging of the γ-aminobutyric acid (GABA) receptor complex has been accomplished using radiolabeled benzodiazepine derivatives, but development of specific presynaptic radioligands targeting the neuronal membrane GABA transporter type 1 (GAT-1) has been less successful. The availability of new structure-activity studies of GAT-1 inhibitors and the introduction of a GAT-1 inhibitor (tiagabine, Gabatril) into clinical use prompted us to reinvestigate the syntheses of PET ligands for this transporter. Initial synthesis and rodent PET studies of N-[11C]methylnipecotic acid confirmed the low brain uptake of that small and polar molecule. The common design approach to improve blood-brain barrier permeability of GAT-1 inhibitors is the attachment of a large lipophilic substituent. We selected an unsymmetrical bis-aromatic residue attached to the ring nitrogen by a vinyl ether spacer from a series recently reported by Wanner and coworkers. Nucleophilic aromatic substitution of an aryl chloride precursor with [18F]fluoride was used to prepare the desired candidate radiotracer ( R, E/ Z)-1-(2-((4-fluoro-2-(4-[18F]fluorobenzoyl)styryl)oxy)ethyl)piperidine-3-carboxylic acid (( R, E/ Z)-[18F]10). PET studies in rats showed no brain uptake, which was not altered by pretreatment of animals with the P-glycoprotein inhibitor cyclosporine A, indicating efflux by Pgp was not responsible. Subsequent PET imaging studies of ( R, E/ Z)-[18F]10 in rhesus monkey brain showed very low brain uptake. Finally, to test if the free carboxylic acid group was the likely cause of poor brain uptake, PET studies were done using the ethyl ester derivative of ( R, E/ Z)-[18F]10. Rapid and significant monkey brain uptake of the ester was observed, followed by a slow washout over 90 min. The blood-brain barrier permeability of the ester supports a hypothesis that the free acid function limits brain uptake of nipecotic acid-based GAT-1 radioligands, and future radiotracer efforts should investigate the use of carboxylic acid bioisosteres.
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Affiliation(s)
- Alexandra R. Sowa
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48105, United States
| | - Allen F. Brooks
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Xia Shao
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Bradford D. Henderson
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Philip Sherman
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Janna Arteaga
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Jenelle Stauff
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Adam C. Lee
- E.I. du Pont de Nemours and Company, DuPont Haskell Global Center for Health Sciences, P.O. Box 30, Newark, Delaware 19714, United States
| | - Robert A. Koeppe
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
| | - Peter J. H. Scott
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48105, United States
| | - Michael R. Kilbourn
- Department of Radiology, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
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Zafar S, Jabeen I. Structure, Function, and Modulation of γ-Aminobutyric Acid Transporter 1 (GAT1) in Neurological Disorders: A Pharmacoinformatic Prospective. Front Chem 2018; 6:397. [PMID: 30255012 PMCID: PMC6141625 DOI: 10.3389/fchem.2018.00397] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 08/20/2018] [Indexed: 02/03/2023] Open
Abstract
γ-Aminobutyric acid (GABA) Transporters (GATs) belong to sodium and chloride dependent-transporter family and are widely expressed throughout the brain. Notably, GAT1 is accountable for sustaining 75% of the synaptic GABA concentration and entails its transport to the GABAA receptors to initiate the receptor-mediated inhibition of post-synaptic neurons. Imbalance in ion homeostasis has been associated with several neurological disorders related to the GABAergic system. However, inhibition of the GABA uptake by these transporters has been accepted as an effective approach to enhance GABAergic inhibitory neurotransmission in the treatment of seizures in epileptic and other neurological disorders. Here, we reviewed computational methodologies including molecular modeling, docking, and molecular dynamic simulations studies to underscore the structure and function of GAT1 in the GABAergic system. Additionally, various SAR and QSAR methodologies have been reviewed to probe the 3D structural features of inhibitors required to modulate GATs activity. Overall, present review provides an overview of crucial role of GAT1 in GABAergic system and its modulation to evade neurological disorders.
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Affiliation(s)
| | - Ishrat Jabeen
- Research Center for Modeling and Simulation, National University of Sciences and Technology, Islamabad, Pakistan
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Marunnan SM, Pulikkal BP, Jabamalairaj A, Bandaru S, Yadav M, Nayarisseri A, Doss VA. Development of MLR and SVM Aided QSAR Models to Identify Common SAR of GABA Uptake Herbal Inhibitors used in the Treatment of Schizophrenia. Curr Neuropharmacol 2018; 15:1085-1092. [PMID: 27919211 PMCID: PMC5725540 DOI: 10.2174/1567201814666161205131745] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Revised: 02/05/2016] [Accepted: 11/03/2016] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Alterations in GABAnergic system are implicated in the pathophysiology of schizophrenia. Available antipsychotics that target GABA receptor form a desirable therapeutic strategy in the treatment regimen of schizophrenia, unfortunately, suffer serious setback due to their prolonged side effects. The present investigation focuses on developing QSAR models from the biological activity of herbal compounds and their derivatives that promise to be alternative candidates to GABA uptake inhibitors. METHODS Three sets of compounds were undertaken in the study to develop QSAR models. The first set consisted of nine compounds which included Magnolol, Honokiol and other GABA acting established compounds. The second set consisted of 16 derivatives of N-diarylalkenylpiperidinecarboxylic acid. The third QSAR dataset was made up of thirty two compounds which were Magnolol and Honokiol derivatives. Multiple linear regressions (MLR) and support vector machine (SVM) supervised quantitative structure-activity relationship (QSAR) models were developed to predict the biological activity of these three sets. The purpose of taking three QSAR sets of diverse chemical structures but identical in their GABA targeting and pharmacological action was to identify common chemical structure features responsible for structure-activity relationship (SAR). RESULTS Linear and non-linear QSAR models confirmed that the three sets shared common structural descriptors derived from WHIM (Weighted Holistic Invariant Molecular descriptors), 3D-MoRSE and Eigenvalue classes. CONCLUSION It was concluded that properties like electro negativity and polarizability play a crucial role in controlling the activity of herbal compounds against GABA receptor.
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Affiliation(s)
- Sahila Mohammed Marunnan
- Department of Biochemistry and Bioinformatics, Karpagam University, Coimbatore- 641 021, Tamil Nadu, India.,Department of Bioinformatics, SIAS-Centre for Scientific Research, Safi Institute of Advanced Study (SIAS), Rasiya Nagar, Vazhayoor East, Malappuram-673633, Kerala, India
| | | | - Anitha Jabamalairaj
- Department of Bioinformatics, SIAS-Centre for Scientific Research, Safi Institute of Advanced Study (SIAS), Rasiya Nagar, Vazhayoor East, Malappuram-673633, Kerala, India
| | - Srinivas Bandaru
- Bioinformatics Research Laboratory, Eminent Biosciences, Vijaynagar, Indore-452010, India
| | - Mukesh Yadav
- Bioinformatics Research Laboratory, Eminent Biosciences, Vijaynagar, Indore-452010, India
| | - Anuraj Nayarisseri
- Bioinformatics Research Laboratory, Eminent Biosciences, Vijaynagar, Indore-452010, India.,In Silico Research Laboratory, LeGene Biosciences, Vijaynagar, Indore-452010, India
| | - Victor Arokia Doss
- Department of Biochemistry, PSG College of Arts and Science, Coimbatore-641 014, India
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Novel heterogeneous catalyst systems based on Pd(0) nanoparticles onto amine functionalized silica-cellulose substrates [Pd(0)-EDA/SCs]: Synthesis, characterization and catalytic activity toward C–C and C–S coupling reactions in water under limiting basic conditions. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.molcata.2015.07.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Sahila MM, Babitha PP, Bandaru S, Nayarisseri A, Doss VA. Molecular docking based screening of GABA (A) receptor inhibitors from plant derivatives. Bioinformation 2015; 11:280-9. [PMID: 26229288 PMCID: PMC4512002 DOI: 10.6026/97320630011280] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 06/25/2015] [Accepted: 06/04/2015] [Indexed: 12/05/2022] Open
Abstract
UNLABELLED The present antipsychotic drugs have known to show serious concerns like extra pyramidal side effects therefore, pursuit for novel antipsychotic GABAnergic drugs has lately focused on the folkloric medicine from plant derivatives as better treatment option of schizophrenia. The present study centers to identify potential inhibitors of plant origin for GABA receptor through in silico approaches. Three compound datasets were undertaken in the study. The first set consisted of seven compounds which included Magnolol, Honokiol and other plant derivatives. The second set consisted of 16 derivatives of N-diarylalkenyl-piperidinecarboxylic acid synthesized by Zheng et al., 2006. The third dataset had thirty two compounds which were Magnolol and Honokiol analogues synthesized by Fuchs et al., 2014. All the compounds were docked at the allosteric site of the GABA (A) receptor. The compounds were further tested for ADMET and biological activity. We observed Honokiol and its derivatives demonstrated superior druglike properties than any compound undertaken in the study. Further, compound 61 [2-(4-methoxyphenyl)-4-propylphenol] of dataset three - a synthetic derivative of honokiol had better profile than its parent compound. In a possible attempt to identify compound with even better efficacious compound than 61, virtual screening was performed, 135 compounds akin to compound 61 were retrieved. Interestingly none of the 135 compounds showed better druggable properties than compound 61. Our in silico pharmacological profiling of compounds is in coherence and is complemented by the findings of Fuchs et al, which also revealed compound 61 to be the good potentiator of GABA receptor. ABBREVIATIONS GABA (A) R - Gamma Amino Butyric Acid Receptor, subtype A, GPCR - G Protein Coupled Receptor, OPLS - Optimized Potentials for Liquid Simulations, PDB - Protein Data Bank, PLP - Piece wise Linear Potential, T.E.S.T - Toxicity Estimation Software Tool, TCM - Traditional Chinese Medicine.
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Affiliation(s)
- Mohammed Marunnan Sahila
- Department of Bioinformatics, School of Life Sciences, Karpagam University, Coimbatore 641021, India
- Department of Bioinformatics, SIAS-Centre for Scientific, Research, Safi Institute of Advanced Study(SIAS) , Rasiya Nagar, Vazhayoor East, Malappuram-673633, Kerala, India
| | | | - Srinivas Bandaru
- Bioinformatics Research Laboratory, Eminent Biosciences, Vijaynagar, Indore - 452010, India
| | - Anuraj Nayarisseri
- Bioinformatics Research Laboratory, Eminent Biosciences, Vijaynagar, Indore - 452010, India
| | - Victor Arokia Doss
- Department of Biochemistry, PSG College of Arts and Science, Coimbatore - 641 014, India
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Kour M, Paul S. Sulfonated carbon/nano-metal oxide composites: a novel and recyclable solid acid catalyst for organic synthesis in benign reaction media. NEW J CHEM 2015. [DOI: 10.1039/c5nj00607d] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel catalytic system based on the use of nano-metal oxides and carbon has been designed and exhibits excellent catalytic activity for acid catalyzed organic reactions.
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Affiliation(s)
- Manmeet Kour
- Department of Chemistry
- University of Jammu
- Jammu-180 006
- India
| | - Satya Paul
- Department of Chemistry
- University of Jammu
- Jammu-180 006
- India
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Jurik A, Reicherstorfer R, Zdrazil B, Ecker GF. Classification of High-Activity Tiagabine Analogs by Binary QSAR Modeling. Mol Inform 2013; 32:415-419. [PMID: 23956803 PMCID: PMC3743161 DOI: 10.1002/minf.201300020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 03/28/2013] [Indexed: 12/01/2022]
Affiliation(s)
- Andreas Jurik
- University of Vienna, Department of Medicinal Chemistry Althanstraße 14, A-1090 Vienna, Austria phone/fax: +431-4277-55110/-9551
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Heteroporphyrins. ADVANCES IN HETEROCYCLIC CHEMISTRY 2012. [DOI: 10.1016/b978-0-12-396531-8.00002-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Saha M, Pal AK, Nandi S. Pd(0) NPs: a novel and reusable catalyst for the synthesis of bis(heterocyclyl)methanes in water. RSC Adv 2012. [DOI: 10.1039/c2ra20445b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Singh K, Sharma S, Sharma A. Unique versatility of Amberlyst 15. An acid and solvent-free paradigm towards synthesis of bis(heterocyclyl)methane derivatives. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.molcata.2011.07.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Bartoli G, Cipolletti R, Di Antonio G, Giovannini R, Lanari S, Marcolini M, Marcantoni E. A convergent approach to (R)-Tiagabine by a regio- and stereocontrolled hydroiodination of alkynes. Org Biomol Chem 2010; 8:3509-17. [PMID: 20532411 DOI: 10.1039/c005042c] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The occurrence of unsaturated systems in natural products combined with the mildness and the wide range of applicability of CeCl(3) promoted methodologies suggest several potential future synthetic applications within the field of total synthesis of biologically active molecules. On this concept, the use of CeCl(3).7H(2)O-NaI system as an efficient heterogeneous promoter has been highlighted in the iodofunctionalization of carbon-carbon triple bonds. The study has shown that this method would be particularly interesting for the stereoselective formation of trisubstituted (Z)- or (E)-iodoalkenes by simply changing the nature of the solvent. The methodology has been successfully applied to the synthesis of (R)-1-[4,4-bis-(3-methyl-2-thienyl)-3-butenyl]-3-piperidinecarboxylic acid , named (R)-Tiagabine, which is a potent and selective gamma-aminobutyric acid (GABA) uptake inhibitor with proven anticonvulsant efficacy in humans.
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Affiliation(s)
- Giuseppe Bartoli
- Department of Organic Chemistry "A. Mangini", University of Bologna, viale Risorgiment 4, I-40136 Bologna, Italy
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Zhuang W, Zhao X, Zhao G, Guo L, Lian Y, Zhou J, Fang D. Synthesis and biological evaluation of 4-fluoroproline and 4-fluoropyrrolidine-2-acetic acid derivatives as new GABA uptake inhibitors. Bioorg Med Chem 2009; 17:6540-6. [PMID: 19703775 DOI: 10.1016/j.bmc.2009.08.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 08/03/2009] [Accepted: 08/04/2009] [Indexed: 11/26/2022]
Abstract
Preparation for the N-alkylated derivatives of enantiomerically pure (2S)-4-fluoroproline and (2S)-4-fluoropyrrolidine-2-acetic acid is described. The final compounds were evaluated as potential GAT-1 uptake inhibitors via cultured cell lines expressing mouse GAT-1. Compared with their corresponding 4-hydroxy compounds, these derivatives exhibited slight improvement on their inhibitory potency, but still much weaker than their corresponding compounds with no substituents at the C-4 of the pyrrolidine moiety, with the most potent affinity being about 1/15 fold as that of Tiagabine. The drastic decrease of their affinity may arise from sharp reduction of their basicity due to strong inductive effect of the 4-fluorine. However the configuration of the C-4 linking fluorine did not have much influence on their affinity for GAT-1.
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Affiliation(s)
- Weiping Zhuang
- Fujian Institute of Microbiology, No. 25, Jinbu road, Fuzhou 350007, China
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Merino P, Mannucci V, Tejero T. Exploring Nitrone Chemistry: Towards the Enantiodivergent Synthesis of 6-Substituted 4-Hydroxypipecolic Acid Derivatives. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800348] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Synthesis and biological evaluation of (R)-N-(diarylmethylthio/sulfinyl)ethyl/propyl-piperidine-3-carboxylic acid hydrochlorides as novel GABA uptake inhibitors. Bioorg Med Chem Lett 2007; 17:3769-73. [PMID: 17517506 DOI: 10.1016/j.bmcl.2007.04.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Revised: 04/02/2007] [Accepted: 04/05/2007] [Indexed: 11/16/2022]
Abstract
A series of new (R)-1-(2-diarylmethylthio/sulfinyl)ethyl-piperidine-3-carboxylic acid hydrochlorides 5a-d/6a-d and (R)-1-(3-diarylmethylthio)propyl-piperidine-3-carboxylic acid hydrochlorides 5'a-d were synthesized and evaluated as gamma-aminobutyric acid uptake inhibitors through cultured cell lines expressing mouse GAT1. Biological screening results demonstrated that the compounds 6a-d with diarylmethylsulfinyl ethyl side chain show more potent GAT1 inhibitory activities than 5a-d/5'a-d with diarylmethylthio ethyl/propyl moieties. Some of them, such as 6a, exhibited excellent inhibitions of [(3)H]-GABA uptake in cultured cells, which is 496-fold higher than (R)-nipecotic acid and 11.5 times less than tiagabine. The synthesis and structure-activity relationships are discussed.
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