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Talukdar A, Ganguly D, Roy S, Das N, Sarkar D. Structural Evolution and Translational Potential for Agonists and Antagonists of Endosomal Toll-like Receptors. J Med Chem 2021; 64:8010-8041. [PMID: 34107682 DOI: 10.1021/acs.jmedchem.1c00300] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Toll-like receptors (TLRs) are members of a large family of evolutionarily conserved pattern recognition receptors (PRRs), which serve as key components of the innate immune system by playing a pivotal role in sensing "nonself" ligands. Endosomal TLRs (TLR3, TLR7, TLR8, and TLR9) can recognize pathogen-derived nucleic acid and initiate an innate immune response because they react against both self- and non-self-origin nucleic acid molecules. Accordingly, both receptor agonists and antagonists are potentially useful in disparate clinical contexts and thus are globally sought after. Recent research has revealed that agonists and antagonists share an overlapping binding region. This Perspective highlights rational medicinal chemistry approaches to elucidate the structural attributes of small molecules capable of agonism or antagonism or of elegantly switching between the two. The structural evolution of different chemotypes can provide the framework for the future development of endosomal TLR agonists and antagonists.
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Affiliation(s)
- Arindam Talukdar
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India.,Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India
| | - Dipyaman Ganguly
- IICB-Translational Research Unit of Excellence, Department of Cancer Biology and Inflammatory Disorders, CSIR-Indian Institute of Chemical Biology, CN6, Sector V, Salt Lake, Kolkata 700091, West Bengal, India.,Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India
| | - Swarnali Roy
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
| | - Nirmal Das
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India.,Academy of Scientific and Innovative Research, Ghaziabad 201002, Uttar Pradesh, India
| | - Dipika Sarkar
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
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Structural analysis reveals TLR7 dynamics underlying antagonism. Nat Commun 2020; 11:5204. [PMID: 33060576 PMCID: PMC7562955 DOI: 10.1038/s41467-020-19025-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 09/25/2020] [Indexed: 12/22/2022] Open
Abstract
Toll-like receptor 7 (TLR7) recognizes both microbial and endogenous RNAs and nucleosides. Aberrant activation of TLR7 has been implicated in several autoimmune diseases including systemic lupus erythematosus (SLE). Here, by modifying potent TLR7 agonists, we develop a series of TLR7-specific antagonists as promising therapeutic agents for SLE. These compounds protect mice against lethal autoimmunity. Combining crystallography and cryo-electron microscopy, we identify the open conformation of the receptor and reveal the structural equilibrium between open and closed conformations that underlies TLR7 antagonism, as well as the detailed mechanism by which TLR7-specific antagonists bind to their binding pocket in TLR7. Our work provides small-molecule TLR7-specific antagonists and suggests the TLR7-targeting strategy for treating autoimmune diseases. A series of Toll-like receptor 7 (TLR7)-specific antagonists and extensive structural analysis reveal the open conformation of the receptor and the structural basis of TLR7 antagonism. One of the compounds shows efficacy in treating mouse model of systemic lupus erythematosus.
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3
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Mukherjee A, Raychaudhuri D, Sinha BP, Kundu B, Mitra M, Paul B, Bandopadhyay P, Ganguly D, Talukdar A. A Chemical Switch for Transforming a Purine Agonist for Toll-like Receptor 7 to a Clinically Relevant Antagonist. J Med Chem 2020; 63:4776-4789. [PMID: 32302115 DOI: 10.1021/acs.jmedchem.0c00011] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Toll-like receptor 7 (TLR7) is an established therapeutic target in myriad autoimmune disorders, but no TLR7 antagonist is available for clinical use to date. Herein, we report a purine scaffold TLR7 antagonist, first-of-its-kind to our knowledge, which was developed by rationally dissecting the structural requirements for TLR7-targeted activity for a purine scaffold. Specifically, we identified a singular chemical switch at C-2 that could make a potent purine scaffold TLR7 agonist to lose agonism and acquire antagonist activity, which could further be potentiated by the introduction of an additional basic center at C-6. We ended up developing a clinically relevant TLR7 antagonist with favorable pharmacokinetics and 70.8% oral bioavailability in mice. Moreover, the TLR7 antagonists depicted excellent selectivity against TLR8. To further validate the in vivo applicability of this novel TLR7 antagonist, we demonstrated its excellent efficacy in preventing TLR7-induced pathology in a preclinical murine model of psoriasis.
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Affiliation(s)
- Ayan Mukherjee
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Deblina Raychaudhuri
- IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata 700032, India
| | - Bishnu Prasad Sinha
- IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata 700032, India
| | - Biswajit Kundu
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India
| | - Mousumi Mitra
- IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata 700032, India
| | - Barnali Paul
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Purbita Bandopadhyay
- IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata 700032, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Dipyaman Ganguly
- IICB-Translational Research Unit of Excellence, CSIR-Indian Institute of Chemical Biology, Kolkata 700032, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Arindam Talukdar
- Department of Organic and Medicinal Chemistry, CSIR-Indian Institute of Chemical Biology, 4 Raja S. C. Mullick Road, Kolkata 700032, West Bengal, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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4
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Akinbobuyi B, Wang L, Upchurch KC, Byrd MR, Chang CA, Quintana JM, Petersen RE, Seifert ZJ, Boquin JR, Oh S, Kane RR. Synthesis and immunostimulatory activity of substituted TLR7 agonists. Bioorg Med Chem Lett 2016; 26:4246-9. [PMID: 27476423 DOI: 10.1016/j.bmcl.2016.07.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 07/20/2016] [Accepted: 07/21/2016] [Indexed: 11/18/2022]
Abstract
Fifteen new substituted adenines were synthesized as potential TLR7 agonists. These compounds, along with 9 previously reported compounds, were analyzed for TLR7 activity and for the selective stimulation of B cell proliferation. Several functionalized derivatives exhibit significant activity, suggesting their potential for use as vaccine adjuvants.
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Affiliation(s)
- Babatope Akinbobuyi
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Lei Wang
- Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Katherine C Upchurch
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Matthew R Byrd
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Charles A Chang
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA
| | - Jeremy M Quintana
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Rachel E Petersen
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Zacharie J Seifert
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - José R Boquin
- Department of Chemistry, Augustana College, 639 38th Street, Rock Island, IL 61201, USA
| | - SangKon Oh
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Robert R Kane
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA; Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA.
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5
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Bilbao N, Vázquez-González V, Aranda MT, González-Rodríguez D. Synthesis of 5-/8-Halogenated or Ethynylated Lipophilic Nucleobases as Potential Synthetic Intermediates for Supramolecular Chemistry. European J Org Chem 2015. [DOI: 10.1002/ejoc.201501026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Akinbobuyi B, Byrd MR, Chang CA, Nguyen M, Seifert ZJ, Flamar AL, Zurawski G, Upchurch KC, Oh S, Dempsey SH, Enke TJ, Le J, Winstead HJ, Boquín JR, Kane RR. Facile syntheses of functionalized toll-like receptor 7 agonists. Tetrahedron Lett 2015; 56:458-460. [PMID: 25601818 DOI: 10.1016/j.tetlet.2014.11.126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Protein conjugates of toll-like receptor 7 agonists have been shown to elicit powerful immune responses. In order to facilitate our studies in this area our group has developed efficient syntheses for a number of functionalized derivatives that retain immune stimulatory activity.
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Affiliation(s)
- Babatope Akinbobuyi
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Matthew R Byrd
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Charles A Chang
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA
| | - Mysa Nguyen
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Zacharie J Seifert
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA
| | - Anne-Laure Flamar
- Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Gerard Zurawski
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA ; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Katherine C Upchurch
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA
| | - SangKon Oh
- Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA ; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
| | - Stephen H Dempsey
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - Thomas J Enke
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - John Le
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - Hunter J Winstead
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - José R Boquín
- Department of Chemistry, Augustana College, 639 38 Street, Rock Island, IL 61201, USA
| | - Robert R Kane
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX 76798, USA ; Institute of Biomedical Studies, Baylor University, One Bear Place #97224, Waco, TX 76798, USA ; Baylor Institute for Immunology Research, Baylor Research Institute, 3434 Live Oak Street, Dallas, TX 75204, USA
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7
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Venkatesh V, Shukla A, Sivakumar S, Verma S. Purine-stabilized green fluorescent gold nanoclusters for cell nuclei imaging applications. ACS APPLIED MATERIALS & INTERFACES 2014; 6:2185-91. [PMID: 24445024 DOI: 10.1021/am405345h] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We report facile one-pot synthesis of water-soluble green fluorescent gold nanoclusters (AuNCs), capped with 8-mercapto-9-propyladenine. The synthesized AuNCs were characterized by Fourier transform infrared (FTIR), powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), (1)H NMR, and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. These nanoclusters show high photostability and biocompatibility. We observed that AuNCs stain cell nuclei with high specificity, where the mechanism of AuNC uptake was established through pathway-specific uptake inhibitors. These studies revealed that cell internalization of AuNCs occurs via a macropinocytosis pathway.
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Affiliation(s)
- V Venkatesh
- Department of Chemistry, ‡Department of Chemical Engineering, Material Science Programme, and §DST Thematic Unit of Excellence on Soft Nanofabrication, Indian Institute of Technology Kanpur , Kanpur, Uttar Pradesh 208016, India
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8
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Chumachenko SA, Shablykin OV, Vasilenko AN, Brovarets VS. Recyclization of 2-methoxy-5-morpholino-1,3-oxazole-4-carbonitrile by benzylamine, phenethylamine, and phenylhydrazine. RUSS J GEN CHEM+ 2013. [DOI: 10.1134/s1070363213090144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Roethle PA, McFadden RM, Yang H, Hrvatin P, Hui H, Graupe M, Gallagher B, Chao J, Hesselgesser J, Duatschek P, Zheng J, Lu B, Tumas DB, Perry J, Halcomb RL. Identification and Optimization of Pteridinone Toll-like Receptor 7 (TLR7) Agonists for the Oral Treatment of Viral Hepatitis. J Med Chem 2013; 56:7324-33. [DOI: 10.1021/jm400815m] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Paul A. Roethle
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Ryan M. McFadden
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Hong Yang
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Paul Hrvatin
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Hon Hui
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Michael Graupe
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Brian Gallagher
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Jessica Chao
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Joseph Hesselgesser
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Paul Duatschek
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Jim Zheng
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Bing Lu
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Daniel B. Tumas
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Jason Perry
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
| | - Randall L. Halcomb
- Departments of †Medicinal Chemistry, ‡Clinical Virology, §Drug Metabolism, ∥Biology, and ⊥Structural Chemistry, Gilead Sciences, 333 Lakeside Drive, Foster City, California 94404, United States
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Nicolaou KC, Ellery SP, Rivas F, Saye K, Rogers E, Workinger TJ, Schallenberger M, Tawatao R, Montero A, Hessell A, Romesberg F, Carson D, Burton D. Synthesis and biological evaluation of 2',4'- and 3',4'-bridged nucleoside analogues. Bioorg Med Chem 2011; 19:5648-69. [PMID: 21840722 PMCID: PMC3348725 DOI: 10.1016/j.bmc.2011.07.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 07/12/2011] [Accepted: 07/13/2011] [Indexed: 10/18/2022]
Abstract
Most nucleosides in solution typically exist in equilibrium between two major sugar pucker forms, N-type and S-type, but bridged nucleosides can be locked into one of these conformations depending on their specific structure. While many groups have researched these bridged nucleosides for the purpose of determining their binding affinity for antisense applications, we opted to look into the potential for biological activity within these conformationally-locked structures. A small library of 2',4'- and 3',4'-bridged nucleoside analogues was synthesized, including a novel 3',4'-carbocyclic bridged system. The synthesized compounds were tested for antibacterial, antitumor, and antiviral activities, leading to the identification of nucleosides possessing such biological activities. To the best of our knowledge, these biologically active compounds represent the first example of 2',4'-bridged nucleosides to demonstrate such properties. The most potent compound, nucleoside 33, exhibited significant antiviral activity against pseudoviruses SF162 (IC(50)=7.0 μM) and HxB2 (IC(50)=2.4 μM). These findings render bridged nucleosides as credible leads for drug discovery in the anti-HIV area of research.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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Zhong QF, Sun LP. An efficient synthesis of 6,9-disubstituted purin-8-ones via copper-catalyzed coupling/cyclization. Tetrahedron 2010. [DOI: 10.1016/j.tet.2010.04.106] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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13
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Weterings JJ, Khan S, van der Heden van Noort GJ, Melief CJ, Overkleeft HS, van der Burg SH, Ossendorp F, van der Marel GA, Filippov DV. 2-Azidoalkoxy-7-hydro-8-oxoadenine derivatives as TLR7 agonists inducing dendritic cell maturation. Bioorg Med Chem Lett 2009; 19:2249-51. [DOI: 10.1016/j.bmcl.2009.02.095] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 02/23/2009] [Accepted: 02/24/2009] [Indexed: 01/24/2023]
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14
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Butler RS, Myers AK, Bellarmine P, Abboud KA, Castellano RK. Highly fluorescent donor–acceptor purines. ACTA ACUST UNITED AC 2007. [DOI: 10.1039/b618171f] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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15
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Parcher BW, Erion DM, Dang Q. An efficient synthesis of 5-aminoimidazol-2-ones via cyclization reactions of 2-aminoacetonitriles and isocyanates. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.01.088] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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