1
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Synthesis and evaluation of a collection of purine-like C-nucleosides as antikinetoplastid agents. Eur J Med Chem 2020; 212:113101. [PMID: 33385837 DOI: 10.1016/j.ejmech.2020.113101] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 12/17/2022]
Abstract
The kinetoplastid parasites Trypanosoma brucei, Trypanosoma cruzi and Leishmania spp. are the causative agents of neglected tropical diseases with a serious burden in several parts of the world. These parasites are incapable of synthesizing purines de novo, and therefore rely on ingenious purine salvage pathways to acquire and process purines from their host. Purine nucleoside analogs that may interfere with these pathways therefore constitute a privileged source of new antikinetoplastid agents. In this study, we synthetized a collection of C-nucleosides employing five different heterocyclic nucleobase surrogates. C-nucleosides are chemically and enzymatically stable and allow for extensive structural modification. Inspired by earlier 7-deazaadenosine nucleosides and known antileishmanial C-nucleosides, we introduced different modifications tailored towards antikinetoplastid activity. Both adenosine and inosine analogs were synthesized with the aim of discovering new antikinetoplastid hits and expanding knowledge of structure-activity relationships. Several promising hits with potent activity against Trypanosoma brucei, Trypanosoma cruzi and Leishmania infantum were discovered, and the nature of the nucleobase surrogate was found to have a profound influence on the selectivity profile of the compounds.
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2
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Chen P, Luo K, Yu X, Yuan X, Liu X, Lin J, Jin Y. Cu-Catalyzed Direct Amination of Cyclic Amides via C-OH Bond Activation Using DMF. Org Lett 2020; 22:6547-6551. [PMID: 32806150 DOI: 10.1021/acs.orglett.0c02320] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herein, we describe a Cu-catalyzed approach to directly accessing aromatic heterocyclic amines from cyclic amides. The most-reported methods for cyclic amide conversions to aromatic heterocyclic amines use an activating group, such as a halogen atom or a trifluoromethane sulfonyl group. However, subsequent elimination of activating groups during the amination process results in significant waste. This copper-catalyzed direct amination of cyclic amides in DMF forms aromatic heterocyclic amines with environmental friendliness and readily available reagents. A plausible radical mechanism has been proposed for the reaction. Meanwhile, the coordinating effect of the N1 atom is key to the success of this reaction, which provides assistance to the copper ions for the activation and amination of C-O bonds.
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Affiliation(s)
- Peng Chen
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
| | - Kaixiu Luo
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
| | - Xianglin Yu
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
| | - Xu Yuan
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
| | - Xiaoyu Liu
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
| | - Jun Lin
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
| | - Yi Jin
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, P.R. China
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3
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Hulpia F, Bouton J, Campagnaro GD, Alfayez IA, Mabille D, Maes L, de Koning HP, Caljon G, Van Calenbergh S. C6-O-alkylated 7-deazainosine nucleoside analogues: Discovery of potent and selective anti-sleeping sickness agents. Eur J Med Chem 2020; 188:112018. [PMID: 31931339 DOI: 10.1016/j.ejmech.2019.112018] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 12/27/2019] [Accepted: 12/27/2019] [Indexed: 01/02/2023]
Abstract
African trypanosomiasis, a deadly infectious disease caused by the protozoan Trypanosoma brucei spp., is spread to new hosts by bites of infected tsetse flies. Currently approved therapies all have their specific drawbacks, prompting a search for novel therapeutic agents. T. brucei lacks the enzymes necessary to forge the purine ring from amino acid precursors, rendering them dependent on the uptake and interconversion of host purines. This dependency renders analogues of purines and corresponding nucleosides an interesting source of potential anti-T. brucei agents. In this study, we synthesized and evaluated a series of 7-substituted 7-deazainosine derivatives and found that 6-O-alkylated analogues in particular showed highly promising in vitro activity with EC50 values in the mid-nanomolar range. SAR investigation of the O-alkyl chain showed that antitrypanosomal activity increased, and also cytotoxicity, with alkyl chain length, at least in the linear alkyl chain series. However, this could be attenuated by introducing a terminal branch point, resulting in the highly potent and selective analogues, 36, 37 and 38. No resistance related to transporter-mediated uptake could be identified, earmarking several of these analogues for further in vivo follow-up studies.
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Affiliation(s)
- Fabian Hulpia
- Laboratory for Medicinal Chemistry (Campus Heymans), Ghent University, Ottergemsesteenweg 460, B-9000, Gent, Belgium
| | - Jakob Bouton
- Laboratory for Medicinal Chemistry (Campus Heymans), Ghent University, Ottergemsesteenweg 460, B-9000, Gent, Belgium
| | - Gustavo D Campagnaro
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, United Kingdom
| | - Ibrahim A Alfayez
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, United Kingdom
| | - Dorien Mabille
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsplein 1 (S7), B-2610, Wilrijk, Belgium
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsplein 1 (S7), B-2610, Wilrijk, Belgium
| | - Harry P de Koning
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8TA, United Kingdom
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Universiteitsplein 1 (S7), B-2610, Wilrijk, Belgium
| | - Serge Van Calenbergh
- Laboratory for Medicinal Chemistry (Campus Heymans), Ghent University, Ottergemsesteenweg 460, B-9000, Gent, Belgium.
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4
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Kershaw Cook LJ, Ramsay ML. Ditopic bis-heteroazolylpyridines for construction of fluorescent silver(I) bridged metalloligands. INORG CHEM COMMUN 2019. [DOI: 10.1016/j.inoche.2019.04.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Novosjolova I, Bizdēna Ē, Turks M. Synthesis and Applications of Azolylpurine and Azolylpurine Nucleoside Derivatives. European J Org Chem 2015. [DOI: 10.1002/ejoc.201403527] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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6
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Samanta R, Narayan R, Bauer JO, Strohmann C, Sievers S, Antonchick AP. Oxidative regioselective amination of chromones exposes potent inhibitors of the hedgehog signaling pathway. Chem Commun (Camb) 2015; 51:925-8. [DOI: 10.1039/c4cc08376h] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A novel selective coupling of chromones with azoles for the synthesis of biologically active compounds was developed.
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Affiliation(s)
- Rajarshi Samanta
- Max-Planck Institute of Molecular Physiology
- Abteilumg Chemische Biologie
- Dortmund
- Germany
| | - Rishikesh Narayan
- Max-Planck Institute of Molecular Physiology
- Abteilumg Chemische Biologie
- Dortmund
- Germany
| | - Jonathan O. Bauer
- Technische Universität Dortmund
- Fakultät für Chemie und Chemische Biologie
- Anorganische Chemie
- Dortmund
- Germany
| | - Carsten Strohmann
- Technische Universität Dortmund
- Fakultät für Chemie und Chemische Biologie
- Anorganische Chemie
- Dortmund
- Germany
| | - Sonja Sievers
- Max-Planck Institute of Molecular Physiology
- Abteilumg Chemische Biologie
- Dortmund
- Germany
| | - Andrey P. Antonchick
- Max-Planck Institute of Molecular Physiology
- Abteilumg Chemische Biologie
- Dortmund
- Germany
- Technische Universität Dortmund
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7
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Novosjolova I, Bizdēna Ē, Turks M. Application of 2,6-diazidopurine derivatives in the synthesis of thiopurine nucleosides. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.09.095] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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8
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Kitchen JA, Olguín J, Kulmaczewski R, White NG, Milway VA, Jameson GNL, Tallon JL, Brooker S. Effect of N4-Substituent Choice on Spin Crossover in Dinuclear Iron(II) Complexes of Bis-Terdentate 1,2,4-Triazole-Based Ligands. Inorg Chem 2013; 52:11185-99. [DOI: 10.1021/ic4014416] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jonathan A. Kitchen
- Department
of Chemistry and the MacDiarmid Institute for Advanced Materials and
Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Juan Olguín
- Department
of Chemistry and the MacDiarmid Institute for Advanced Materials and
Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Rafal Kulmaczewski
- Department
of Chemistry and the MacDiarmid Institute for Advanced Materials and
Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Nicholas G. White
- Department
of Chemistry and the MacDiarmid Institute for Advanced Materials and
Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Victoria A. Milway
- Department
of Chemistry and the MacDiarmid Institute for Advanced Materials and
Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Guy N. L. Jameson
- Department
of Chemistry and the MacDiarmid Institute for Advanced Materials and
Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Jeffery L. Tallon
- MacDiarmid
Institute for Advanced Materials and Nanotechnology, Callaghan Innovation, P.O. Box 31310, Lower Hutt 5040, New Zealand
| | - Sally Brooker
- Department
of Chemistry and the MacDiarmid Institute for Advanced Materials and
Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
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9
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Kovaļovs A, Novosjolova I, Bizdēna Ē, Bižāne I, Skardziute L, Kazlauskas K, Jursenas S, Turks M. 1,2,3-Triazoles as leaving groups in purine chemistry: a three-step synthesis of N6-substituted-2-triazolyl-adenine nucleosides and photophysical properties thereof. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2012.11.095] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Zhang Q, Cheng G, Huang YZ, Qu GR, Niu HY, Guo HM. Regioselective N9 alkylation of purine rings assisted by β-cyclodextrin. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.07.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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Kokatla HP, Lakshman MK. Two-step, one-pot synthesis of inosine, guanosine, and 2'-deoxyguanosine O6-ethers via intermediate O6-(benzotriazol-1-yl) derivatives. CURRENT PROTOCOLS IN NUCLEIC ACID CHEMISTRY 2012; Chapter 1:Unit1.26. [PMID: 22700333 DOI: 10.1002/0471142700.nc0126s49] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A simple method for the etherification at the O(6)-position of silyl-protected inosine, guanosine, and 2'-deoxyguanosine is described. Typically, a THF solution of the silylated nucleoside is treated with 1H-benzotriazol-1-yloxy-tris(dimethylamino)phosphonium hexafluorophosphate (BOP) and Cs(2)CO(3) under a nitrogen atmosphere. Conversion to the O(6)-(benzotriazol-1-yl) ethers occurs within about 10 min for inosine, and within about 60 min for guanosine and 2'-deoxyguanosine. Then, for reaction with alcohols, the reaction mixture is evaporated and the O(6)-(benzotriazol-1-yl) ether is treated with Cs(2)CO(3) and an appropriate alcohol, at room temperature. On the other hand, for reaction with phenols, Cs(2)CO(3) and the appropriate phenol are added to the reaction mixture without evaporation, and the reaction is carried out at 70°C. Subsequently, workup, isolation, and purification lead to the requisite O(6)-alkyl or O(6)-aryl ethers in good to excellent yields.
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Affiliation(s)
- Hari Prasad Kokatla
- The City College and The City University of New York, New York City, NY, USA
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12
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Cho JH, Coats SJ, Schinazi RF. Efficient synthesis of exo-N-carbamoyl nucleosides: application to the synthesis of phosphoramidate prodrugs. Org Lett 2012; 14:2488-91. [PMID: 22554490 DOI: 10.1021/ol300777p] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An efficient protection protocol for the 6-exo-amino group of purine nucleosides with various chloroformates was developed utilizing N-methylimidazole (NMI). The reaction of an exo-N(6)-group of adenosine analogue 1 with alkyl/and aryl chloroformates under optimized conditions provided the N(6)-carbamoyl adenosines (2a-j) in good to excellent yields. The reaction of N(6)-Cbz-protected nucleosides (5a-c) with phenyl phosphoryl chloride (7) using t-BuMgCl followed by catalytic hydrogenation afforded the corresponding phosphoramidate pronucleotides (8a-c) in excellent yield.
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Affiliation(s)
- Jong Hyun Cho
- Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine , and Veterans Affairs Medical Center, Decatur, Georgia 30033, United States, and RFS Pharma, LLC , 1860 Montreal Road, Tucker, Georgia 30084, United States
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13
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Andrei M, Bakkebø T, Klaveness J, Taskén K, Undheim K. Stereoselective synthesis of (RP)-8-substituted-N⁶-acylated and N⁶-alkylated adenosine-3',5'-cyclic phosphorothioic acids as cAMP antagonists. Eur J Med Chem 2011; 46:5935-40. [PMID: 22041460 DOI: 10.1016/j.ejmech.2011.10.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Revised: 09/29/2011] [Accepted: 10/02/2011] [Indexed: 01/29/2023]
Abstract
N(6)-Monoalkylated, N(6)-dialkylated and N(6)-acylated (R(P))-adenosine 3',5'-cyclic phosphorothioic acids have been prepared by stereoselective syntheses from cAMP for a study of protein kinase A antagonist activity. The antagonist activity of the parent primary 6-amino cAMP derivative was reduced after N-monoalkylation. No significant activity was detected in the N,N-dialkylated derivative. Mono N-acylation had little effect on the activity. Hydrogen bonding involving the 6-amino group in cAMPS seems necessary for activity.
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14
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Isakovic L, Saavedra OM, Llewellyn DB, Claridge S, Zhan L, Bernstein N, Vaisburg A, Elowe N, Petschner AJ, Rahil J, Beaulieu N, Gauthier F, MacLeod AR, Delorme D, Besterman JM, Wahhab A. Constrained (l-)-S-adenosyl-l-homocysteine (SAH) analogues as DNA methyltransferase inhibitors. Bioorg Med Chem Lett 2009; 19:2742-6. [DOI: 10.1016/j.bmcl.2009.03.132] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Revised: 03/23/2009] [Accepted: 03/25/2009] [Indexed: 11/29/2022]
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15
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Kang F, Sui Z, Murray WV. Phosphonium Coupling in the Direct Bond Formations of Tautomerizable Heterocycles via C–OH Bond Activation. European J Org Chem 2009. [DOI: 10.1002/ejoc.200801004] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Fu‐An Kang
- Johnson & Johnson Pharmaceutical Research and Development, LLC 665 Stockton Drive, Exton, PA 19341, USA, Fax: +1‐610‐458‐8249
| | - Zhihua Sui
- Johnson & Johnson Pharmaceutical Research and Development, LLC 665 Stockton Drive, Exton, PA 19341, USA, Fax: +1‐610‐458‐8249
| | - William V. Murray
- Johnson & Johnson Pharmaceutical Research and Development, LLC 665 Stockton Drive, Exton, PA 19341, USA, Fax: +1‐610‐458‐8249
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16
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Lakshman MK, Choudhury A, Bae S, Rochttis E, Pradhan P, Kumar A. Synthesis of N6 , N6-Dialkyl Adenine Nucleosides With In Situ Formed Hexaalkylphosphorus Triamides. European J Org Chem 2008; 2009:152-159. [PMID: 23930082 DOI: 10.1002/ejoc.200800752] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Reactions between secondary amines and phosphorus trichloride (PCl3) leads to the formation of the corresponding tris(dialkylamino)phosphines or hexaalkylphosphorus triamides [HAPT: (R2N)3P]. Reaction of silyl-protected 2'-deoxyinosine and acetyl-protected inosine with the in situ formed HAPT and iodine (I2) leads to the formation of N6,N6-dialkyl adenosine and 2'-deoxyadenosine. In some cases the stoichiometry of the amine is important as also the use of a tertiary amine base. The effect of amine stoichiometry on the reaction of HAPT with I2 has been studied by 31P{1H} NMR.
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Affiliation(s)
- Mahesh K Lakshman
- Department of Chemistry, The City College and The City University of New York, 160 Convent Avenue, New York, NY 10031-9198, U.S.A
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17
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Bae S, Lakshman MK. A Novel Polymer Supported Approach to Nucleoside Modification. J Org Chem 2008; 73:3707-13. [PMID: 18429630 DOI: 10.1021/jo702558n] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Suyeal Bae
- The City College and The City University of New York, 160 Convent Avenue, New York, New York 10031-9198
| | - Mahesh K. Lakshman
- The City College and The City University of New York, 160 Convent Avenue, New York, New York 10031-9198
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18
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Ikejiri M, Saijo M, Morikawa S, Fukushi S, Mizutani T, Kurane I, Maruyama T. Synthesis and biological evaluation of nucleoside analogues having 6-chloropurine as anti-SARS-CoV agents. Bioorg Med Chem Lett 2007; 17:2470-3. [PMID: 17336519 PMCID: PMC7126875 DOI: 10.1016/j.bmcl.2007.02.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2006] [Revised: 01/22/2007] [Accepted: 02/09/2007] [Indexed: 12/16/2022]
Abstract
Nucleoside analogues that have 6-chloropurine as the nucleobase were synthesized and evaluated for anti-SARS-CoV activity by plaque reduction and yield reduction assays in order to develop novel anti-SARS-CoV agents. Among these analogues, two compounds, namely, 1 and 11, exhibited promising anti-SARS-CoV activity that was comparable to those of mizoribine and ribavirin, which are known anti-SARS-CoV agents. Moreover, we observed several SAR trends such as the antiviral effects of the 6-chloropurine moiety, unprotected 5′-hydroxyl group and benzoylated 5′-hydroxyl group.
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Affiliation(s)
- Masahiro Ikejiri
- Faculty of Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan
| | - Masayuki Saijo
- Special Pathogens Laboratory, Department of Virology 1, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan
| | - Shigeru Morikawa
- Special Pathogens Laboratory, Department of Virology 1, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan
| | - Shuetsu Fukushi
- Special Pathogens Laboratory, Department of Virology 1, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan
| | - Tetsuya Mizutani
- Special Pathogens Laboratory, Department of Virology 1, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan
| | - Ichiro Kurane
- Special Pathogens Laboratory, Department of Virology 1, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan
| | - Tokumi Maruyama
- Faculty of Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan
- Corresponding author.
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19
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Zhong M, Robins MJ. Regiospecific N9 Alkylation of 6-(Heteroaryl)purines: Shielding of N7 by a Proximal Heteroaryl C−H1. J Org Chem 2006; 71:8901-6. [PMID: 17081021 DOI: 10.1021/jo061759h] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Purine alkylations have been plagued with formation of mixtures of N9 (usually desired), N7, and other regioisomers. We have developed methods for synthesis of 6-(azolyl)purine derivatives whose X-ray crystal structures show essentially coplanar conformations of the linked azole-purine rings. Such ring orientations position the C-H of the azole above N7 of the purine, which results in protection of N7 from alkylating agents. Treatment of 6-(2-butylimidazol-1-yl)-2-chloropurine (9) with sodium hydride in DMF followed by addition of ethyl iodide resulted in exclusive formation of 6-(2-butylimidazol-1-yl)-2-chloro-9-ethylpurine (10), whereas identical treatment of 2-chloro-6-(4,5-diphenylimidazol-1-yl)purine (11) produced a regioisomeric mixture 12/13 (N9/N7, approximately 5:1). The linked imidazole and purine rings are coplanar in 9 (the butyl side chain is extended away from the purine ring and C-H is over N7) but are rotated approximately 57 degrees in 11, and the more bulky azole substituent in 11 did not prevent formation of the minor N7 regioisomer 13. Access to various regioisomerically pure 9-alkylpurines is now readily available.
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Affiliation(s)
- Minghong Zhong
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602-5700, USA
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20
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Godzina P, Adrych-Rozek K, Markiewicz WT. Synthetic Oligonucleotide Combinatorial Libraries. 3. Synthesis of Polyamevonucleosides. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/07328319908044615] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Przemyslaw Godzina
- a Institute of Bioorganic Chemistry, Polish Academy of Sciences , Noskowskiego 12, PL-61704 , Poznah , Poland
| | - Katarzyna Adrych-Rozek
- a Institute of Bioorganic Chemistry, Polish Academy of Sciences , Noskowskiego 12, PL-61704 , Poznah , Poland
| | - Wojciech T. Markiewicz
- a Institute of Bioorganic Chemistry, Polish Academy of Sciences , Noskowskiego 12, PL-61704 , Poznah , Poland
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21
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Markiewicz WT, Godzina P, Markiewicz M. Synthesis of Polyaminooligonucleotides and Their Combinatorial Libraries. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/07328319908044749] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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22
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Lagisetty P, Russon LM, Lakshman MK. A General Synthesis of C6-Azolyl Purine Nucleosides. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200504565] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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23
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Lagisetty P, Russon LM, Lakshman MK. A General Synthesis of C6-Azolyl Purine Nucleosides. Angew Chem Int Ed Engl 2006; 45:3660-3. [PMID: 16639768 DOI: 10.1002/anie.200504565] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Pallavi Lagisetty
- Department of Chemistry, The City College and The City University of New York, 138th Street at Convent Avenue, New York, NY 10031, USA
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24
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Zhong M, Nowak I, Cannon JF, Robins MJ. Structure and Synthesis of 6-(Substituted-imidazol-1-yl)purines: Versatile Substrates for Regiospecific Alkylation and Glycosylation at N91. J Org Chem 2006; 71:4216-21. [PMID: 16709063 DOI: 10.1021/jo060340o] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
X-ray crystal structures of several 6-(azolyl)purine base and nucleoside derivatives show essentially coplanar conformations of the purine and appended 6-(azolyl) rings. However, the planes of the purine and imidazole rings are twisted approximately 57 degrees in a 2-chloro-6-(4,5-diphenylimidazol-1-yl)purine nucleoside, and a twist angle of approximately 61 degrees was measured between the planes of the purine and pyrrole rings in the structure of a 6-(2,5-dimethylpyrrol-1-yl)purine nucleoside derivative. Shielding "above" N7 of the purine ring by a proximal C-H on the 6-azolyl moiety is apparent with the coplanar compounds, but this effect is diminished in those without coplanarity. Syntheses of 6-(azolyl)purines from both base and nucleoside starting materials are described. Treatment of 2,6-dichloropurine with imidazole gave 2-chloro-6-(imidazol-1-yl)purine. Modified Appel reactions at C6 of trityl-protected hypoxanthine and guanine derivatives followed by detritylation gave 6-(imidazol-1-yl)- and 2-amino-6-(imidazol-1-yl)purines. Imidazole was introduced at C6 of 2',3',5'-tri-O-acetylinosine by a modified Appel reaction, and solvolysis of the glycosyl linkage gave 6-(imidazol-1-yl)purine. Guanosine triacetate was transformed into the protected 2,6-dichloropurine nucleoside, which was subjected to S(N)Ar displacement with imidazoles at C6 followed by glycosyl solvolysis to provide 2-chloro-6-(substituted-imidazol-1-yl)purines. Potential applications of these purine derivatives are outlined.
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Affiliation(s)
- Minghong Zhong
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602-5700, USA
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25
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Nowak I, Jones CT, Robins MJ. Selective removal of the 2'- and 3'-O-acyl groups from 2',3',5'-tri-O-acylribonucleoside derivatives with lithium trifluoroethoxide. J Org Chem 2006; 71:3077-81. [PMID: 16599602 DOI: 10.1021/jo0600104] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Selective cleavage of O2' and O3' ester groups from ribonucleoside derivatives has been accomplished with Dowex 1 x 2 (CF3CH2O-) in 2,2,2-trifluoroethanol (TFE) or lithium trifluoroethoxide/TFE. Deacylations with Li+ -OCH2CF3/TFE proceed at ambient temperature (or with mild heating) to give the 5'-O-acyl derivatives in superior yields and higher purity than prior approaches for selective O2' and O3' ester deprotection.
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Affiliation(s)
- Ireneusz Nowak
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602-5700, USA
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26
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Dirat O, Elliott JM, Jelley RA, Jones AB, Reader M. Expeditious synthesis of novel NK1 antagonists based on a 1,2,4-trisubstituted cyclohexane. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2005.12.067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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27
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Zhong M, Nowak I, Robins MJ. 6-(2-Alkylimidazol-1-yl)purines Undergo Regiospecific Glycosylation at N9. Org Lett 2005; 7:4601-3. [PMID: 16209489 DOI: 10.1021/ol051573p] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] Regioselective control of glycosylation of purines at N9 (versus N7) has been a continuing challenge. We now report Lewis acid catalyzed regiospecific glycosylations of 6-(2-alkylimidazol-1-yl)purines at N9. The 6-(2-alkyl)imidazole moiety also functions as a versatile leaving group that can be replaced by nucleophiles (S(N)Ar) and aryl groups (Suzuki cross-coupling).
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Affiliation(s)
- Minghong Zhong
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602-5700, USA
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28
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Liu J, Robins MJ. Fluoro, Alkylsulfanyl, and Alkylsulfonyl Leaving Groups in Suzuki Cross-Coupling Reactions of Purine 2‘-Deoxynucleosides and Nucleosides. Org Lett 2005; 7:1149-51. [PMID: 15760161 DOI: 10.1021/ol050063s] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] Protected 2'-deoxynucleoside and nucleoside derivatives of 6-fluoropurine, 6-(3-methylbutyl)sulfanylpurine, and 6-(3-methylbutyl)ylsulfonylpurine undergo nickel- or palladium-mediated C-C cross-coupling with arylboronic acids to give good yields of 6-arylpurine products.
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Affiliation(s)
- Jiangqiong Liu
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602-5700, USA
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29
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Liu J, Robins MJ. Azoles as Suzuki Cross-Coupling Leaving Groups: Syntheses of 6-Arylpurine 2‘-Deoxynucleosides and Nucleosides from 6-(Imidazol-1-yl)- and 6-(1,2,4-Triazol-4-yl)purine Derivatives1. Org Lett 2004; 6:3421-3. [PMID: 15355067 DOI: 10.1021/ol048490d] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] 6-(Imidazol-1-yl)-, 6-(benzimidazol-1-yl)-, and 6-(1,2,4-triazol-4-yl)purine nucleosides undergo a nickel-mediated C-C cross-coupling of azole-substituted purine derivatives with arylboronic acids to give good yields of 6-arylpurine nucleosides.
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Affiliation(s)
- Jiangqiong Liu
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602-5700, USA
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30
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Shallop AJ, Gaffney BL, Jones RA. Use of 13C as an indirect tag in 15N specifically labeled nucleosides. Syntheses of [8-13C-1,7,NH2-15N3]adenosine, -guanosine, and their deoxy analogues. J Org Chem 2004; 68:8657-61. [PMID: 14575499 DOI: 10.1021/jo0345446] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have previously reported the use of a 13C tag at the C2 of 15N-multilabeled purine nucleosides to distinguish the adjacent-labeled 15N atoms from those in an untagged nucleoside. We now introduce the use of an indirect tag at the C8 of 15N7-labeled purine nucleosides. This tag allows unambiguous differentiation between a pair of 15N7-labeled purines in which only one is 13C8 labeled. Although the very small C8-N7 coupling (<1 Hz) precludes its direct detection in 1D 15N spectra, 2D 1H-15N NMR experiments display the large C8-H8 coupling (>200 Hz) because H8 is coupled to both N7 and C8. The 13C8 atom is introduced by means of a ring closure of the exocyclic amino groups of a pyrimidinone using [13C]sodium ethyl xanthate. Here, we present methods for the syntheses of [8-13C-1,7,NH2-15N3]adenosine, -guanosine, and their deoxy analogues.
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Affiliation(s)
- Anthony J Shallop
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
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31
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Carvalho MA, Esteves TM, Proença MF, Booth BL. Efficient conversion of 6-cyanopurines into 6-alkoxyformimidoylpurines. Org Biomol Chem 2004; 2:1019-24. [PMID: 15034625 DOI: 10.1039/b400171k] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An extremely simple method for the selective synthesis of 9-aryl and 9-alkyl 6-alkoxy or 6-alkoxyformimidoylpurines from the corresponding 6-cyanopurines is described. The reaction is carried out with methanol or ethanol in the presence of DBU. At room temperature, nucleophilic attack by the primary alcohol occurs selectively on the cyano carbon atom, leading to 6-alkoxyformimidoylpurines in good yields. Heating the reaction mixture at a temperature greater than or equal to 78 degrees C leads to nucleophilic substitution of the substituent in the 6-position by the alkoxy group, generating the corresponding 6-alkoxypurines, also in excellent yields. The 6-alkoxyformimidoylpurines were used as intermediates in the synthesis of 6-carboxamidinopurines by reaction with methylamine (for 9-methylpurine 5a) or methyl ammonium chloride (for 9-arylpurines and 5b and 5c).
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Affiliation(s)
- M Alice Carvalho
- Departamento de Química, Universidade do Minho, Campus de Gualtar, 4710 Braga, Portugal
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32
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Nowak I, Robins MJ. Protection of the amino group of adenosine and guanosine derivatives by elaboration into a 2,5-dimethylpyrrole moiety. Org Lett 2003; 5:3345-8. [PMID: 12943423 DOI: 10.1021/ol035264f] [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: 11/30/2022]
Abstract
[reaction: see text] Protection of the amino group of adenine and guanine nucleosides was effected by heating the substrates in 2,5-hexanedione. The resulting 2,5-dimethylpyrrole adducts were stable toward bases but were hydrolyzed with TFA/H(2)O to regenerate the amino function.
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Affiliation(s)
- Ireneusz Nowak
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602-5700, USA
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33
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Lakshman MK. Palladium-catalyzed C–N and C–C cross-couplings as versatile, new avenues for modifications of purine 2′-deoxynucleosides. J Organomet Chem 2002. [DOI: 10.1016/s0022-328x(02)01267-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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34
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Raboisson P, Baurand A, Cazenave JP, Gachet C, Retat M, Spiess B, Bourguignon JJ. Novel antagonists acting at the P2Y(1) purinergic receptor: synthesis and conformational analysis using potentiometric and nuclear magnetic resonance titration techniques. J Med Chem 2002; 45:962-72. [PMID: 11831909 DOI: 10.1021/jm0104062] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The human P2Y(1) receptor is widely distributed in many tissues and has a classical structure of a G protein-coupled receptor. Activated by adenosine-5'-diphosphate (ADP), this receptor is essential for platelet aggregation. In the present paper, we describe the synthesis of novel P2Y(1) antagonists that could be of interest at least as tools to define the physiological roles of the P2Y(1) receptor, at best as new antithrombotic agents. Thus, we prepared the 2,N(6)-dimethyl-2'-deoxyadenosine-3',5'-bisphosphate derivative, 1e. The biological activity was demonstrated by the ability of compound 1e to inhibit ADP-induced platelet aggregation, shape change, and intracellular calcium rise. This compound was a full antagonist at the P2Y(1) receptor with a pA(2) value of 7.11 +/- 0.11 and was found to be 4-fold more potent than the reference N(6)-methyl-2'-deoxyadenosine-3',5'-bisphosphate (1a, pA(2) = 6.55 +/- 0.05), revealing the potency-enhancing effects of the 2-methyl group. The better activity of 1e as compared to 1a was analyzed using both potentiometric and nuclear magnetic resonance titration techniques, which highlighted specific conformational features of this compound. These results clearly indicate the preference for both compounds for an anti conformation at the N-glycosyl linkage. Furthermore, the percentage of S conformer of 1e is close to that of 1a, which is nearly 70% at pH = 2.8 and increases dramatically when pH increases. From the macroprotonation constants, it can be noted that compound 1e is significantly more basic than 1a. This is indeed expected for the N1 adenine nitrogen due to the electron-donating character of the methyl moiety. By considering the microconstants of the phosphate groups, the higher basicity of P3 and P5 for 1e may be due to the decrease in the local dielectric constant induced by the substitution of the hydrogen atom by a more lipophilic methyl group. Thus, it may be suggested that the gain in activity of 1e when compared to the reference compound 1a would result from its gain in basicity rather than steric and conformational modifications. The synthesis of the first selective radioligand acting at the P2Y(1) receptor ([(33)P]-N(6)-methyl-2'-deoxyadenosine-3',5'-bisphosphate, 17) is also reported and will be used in the future for efficient screening needed for drug optimization.
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Affiliation(s)
- Pierre Raboisson
- Laboratoire de Pharmacochimie de la Communication Cellulaire, UMR 7081 du CNRS, Faculté de Pharmacie, Université Louis Pasteur, 74, Route du Rhin, 67401 Illkirch Cedex, France
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35
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Robins MJ, Miles RW, Samano MC, Kaspar RL. Syntheses of puromycin from adenosine and 7-deazapuromycin from tubercidin, and biological comparisons of the 7-aza/deaza pair. J Org Chem 2001; 66:8204-10. [PMID: 11722226 DOI: 10.1021/jo010935d] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protection (O5') of 2',3'-anhydroadenosine with tert-butyldiphenylsilyl chloride and epoxide opening with dimethylboron bromide gave the 3'-bromo-3'-deoxy xylo isomer which was treated with benzylisocyanate to give the 2'-O-(N-benzylcarbamoyl) derivative. Ring closure gave the oxazolidinone, and successive deprotection concluded an efficient route to 3'-amino-3'-deoxyadenosine. Analogous treatment of the antibiotic tubercidin [7-deazaadenosine; 4-amino-7-(beta-D-ribofuranosyl)pyrrolo[2,3-d]pyrimidine] gave 3'-amino-3'-deoxytubercidin. Trifluoroacetylation of the 3'-amino function, elaboration of the heterocyclic amino group into a (1,2,4-triazol-4-yl) ring with N,N'-bis[(dimethylamino)methylene]hydrazine, and nucleophilic aromatic substitution with dimethylamine gave puromycin aminonucleoside [9-(3-amino-3-deoxy-beta-D-ribofuranosyl)-6-(dimethylamino)purine] and its 7-deaza analogue. Aminoacylation [BOC-(4-methoxy-L-phenylalanine)] and deprotection gave puromycin and 7-deazapuromycin. Most reactions gave high yields at or below ambient temperature. Equivalent inhibition of protein biosynthesis in a rabbit reticulocyte system and parallel growth inhibition of several bacteria were observed with the 7-aza/deaza pair. Replacement of N7 in the purine ring of puromycin by "CH" has no apparent effect on biological activity.
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Affiliation(s)
- M J Robins
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602-5700, USA.
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36
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2-Amino-6-(1,2,4-triazol-4-yl)-purine: a useful intermediate in the synthesis of 9-alkylguanines. Tetrahedron Lett 2000. [DOI: 10.1016/s0040-4039(00)01236-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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37
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Fujii T, Itaya T. The Chemistry of Nx,Ny,Nz-Trimethyladenines and More Highly N-Methylated Adenines. HETEROCYCLES 1999. [DOI: 10.3987/rev-98-517] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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38
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Pagano AR, Zhao H, Shallop A, Jones RA. Syntheses of [1,7-15N2]- and [1,7,NH2-15N3]Adenosine and 2‘-Deoxyadenosine via an N1-Alkoxy-Mediated Dimroth Rearrangement. J Org Chem 1998. [DOI: 10.1021/jo9718152] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alex R. Pagano
- Department of Chemistry, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855
| | - Hong Zhao
- Department of Chemistry, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855
| | - Anthony Shallop
- Department of Chemistry, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855
| | - Roger A. Jones
- Department of Chemistry, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855
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