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Matsushima Y, Ogawa Y, Nishi K, Nakata K. Concise synthesis of amino acid component of amicoumacins via dihydrooxazine formation through intramolecular conjugate addition. Biosci Biotechnol Biochem 2023; 87:131-137. [PMID: 36416802 DOI: 10.1093/bbb/zbac182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 11/02/2022] [Indexed: 11/24/2022]
Abstract
Amicoumacins are a family of antibiotics with a variety of important bioactivities. A concise and efficient method was developed for synthesizing the amino acid component of amicoumacins via the corresponding dihydrooxazine intermediate. The dihydrooxazine ring was formed with complete stereoselectivity through an intramolecular conjugate addition of a δ-trichloroacetimidoyloxy-α,β-unsaturated ester, which was obtained from a known 4,6-O-p-methoxybenzylidene-protected d-glucose. The synthesis developed in this study can be used to synthesize the building blocks of amicoumacins and can likely be adapted for the synthesis of other types of molecules possessing dihydrooxazine rings or amino alcohol moieties.
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Affiliation(s)
- Yoshitaka Matsushima
- Department of Agricultural Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, Japan
| | - Yukako Ogawa
- Department of Agricultural Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, Japan
| | - Katsuya Nishi
- Department of Agricultural Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, Japan
| | - Kyosuke Nakata
- Department of Agricultural Chemistry, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo, Japan
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2
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Matsushima Y, Orita M. Concise synthesis of the Taxol side chain and demethoxy-4-epi-cytoxazone via oxazoline formation through intramolecular benzylic substitution of a bis-trichloroacetimidate. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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3
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Ortiz CLD, Completo GC, Nacario RC, Nellas RB. Potential Inhibitors of Galactofuranosyltransferase 2 (GlfT2): Molecular Docking, 3D-QSAR, and In Silico ADMETox Studies. Sci Rep 2019; 9:17096. [PMID: 31745103 PMCID: PMC6863818 DOI: 10.1038/s41598-019-52764-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/01/2019] [Indexed: 11/08/2022] Open
Abstract
A strategy in the discovery of anti-tuberculosis (anti-TB) drug involves targeting the enzymes involved in the biosynthesis of Mycobacterium tuberculosis' (Mtb) cell wall. One of these enzymes is Galactofuranosyltransferase 2 (GlfT2) that catalyzes the elongation of the galactan chain of Mtb cell wall. Studies targeting GlfT2 have so far produced compounds showing minimal inhibitory activity. With the current challenge of designing potential GlfT2 inhibitors with high inhibition activity, computational methods such as molecular docking, receptor-ligand mapping, molecular dynamics, and Three-Dimensional-Quantitative Structure-Activity Relationship (3D-QSAR) were utilized to deduce the interactions of the reported compounds with the target enzyme and enabling the design of more potent GlfT2 inhibitors. Molecular docking studies showed that the synthesized compounds have binding energy values between -3.00 to -6.00 kcal mol-1. Two compounds, #27 and #31, have registered binding energy values of -8.32 ± 0.01, and -8.08 ± 0.01 kcal mol-1, respectively. These compounds were synthesized as UDP-Galactopyranose mutase (UGM) inhibitors and could possibly inhibit GlfT2. Interestingly, the analogs of the known disaccharide substrate, compounds #1-4, have binding energy range of -10.00 to -19.00 kcal mol-1. The synthesized and newly designed compounds were subjected to 3D-QSAR to further design compounds with effective interaction within the active site. Results showed improved binding energy from -6.00 to -8.00 kcal mol-1. A significant increase on the binding affinity was observed when modifying the aglycon part instead of the sugar moiety. Furthermore, these top hit compounds were subjected to in silico ADMETox evaluation. Compounds #31, #70, #71, #72, and #73 were found to pass the ADME evaluation and throughout the screening, only compound #31 passed the predicted toxicity evaluation. This work could pave the way in the design and synthesis of GlfT2 inhibitors through computer-aided drug design and can be used as an initial approach in identifying potential novel GlfT2 inhibitors with promising activity and low toxicity.
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Affiliation(s)
- Christopher Llynard D Ortiz
- Institute of Chemistry, College of Arts and Sciences, University of the Philippines Los Banos, College, Laguna, 4031, Philippines
- Institute of Chemistry, College of Science, University of the Philippines Diliman, Diliman, Quezon City, 1101, Philippines
| | - Gladys C Completo
- Institute of Chemistry, College of Arts and Sciences, University of the Philippines Los Banos, College, Laguna, 4031, Philippines
| | - Ruel C Nacario
- Institute of Chemistry, College of Arts and Sciences, University of the Philippines Los Banos, College, Laguna, 4031, Philippines
| | - Ricky B Nellas
- Institute of Chemistry, College of Science, University of the Philippines Diliman, Diliman, Quezon City, 1101, Philippines.
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4
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Short synthesis of epi-cytoxazone via oxazoline formation through intramolecular benzylic substitution of a bis-trichloroacetimidate. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2017.11.057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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5
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Cheung ST, Miller MS, Pacoma R, Roland J, Liu J, Schumacher AM, Hsieh-Wilson LC. Discovery of a Small-Molecule Modulator of Glycosaminoglycan Sulfation. ACS Chem Biol 2017; 12:3126-3133. [PMID: 29099173 DOI: 10.1021/acschembio.7b00885] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glycosaminoglycans (GAGs) play critical roles in diverse processes ranging from viral infection to neuroregeneration. Their regiospecific sulfation patterns, which are generated by sulfotransferases, are key structural determinants that underlie their biological activity. Small-molecule modulators of these sulfotransferases could serve as powerful tools for understanding the physiological functions of GAGs, as well as potential therapeutic leads for human diseases. Here, we report the development of the first cell-permeable, small-molecule inhibitor selective for GAG sulfotransferases, which was obtained using a high-throughput screen targeted against Chst15, the sulfotransferase responsible for biosynthesis of chondroitin sulfate-E (CS-E). We demonstrate that the molecule specifically inhibits GAG sulfotransferases in vitro, decreases CS-E and overall sulfation levels on cell-surface and secreted chondroitin sulfate proteoglycans (CSPGs), and reverses CSPG-mediated inhibition of axonal growth. These studies pave the way toward a new set of pharmacological tools for interrogating GAG sulfation-dependent processes and may represent a novel therapeutic approach for neuroregeneration.
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Affiliation(s)
- Sheldon T. Cheung
- Division
of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Michelle S. Miller
- Division
of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Reynand Pacoma
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United States
| | - Jason Roland
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United States
| | - Jian Liu
- Division
of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Andrew M. Schumacher
- Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, California 92121, United States
| | - Linda C. Hsieh-Wilson
- Division
of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
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Gade M, Chaudhary PM, Thulasiram HV, Kikkeri R. Engineering Cell Surface Glycans with Carbohydrate Enantiomers to Alter Bacterial Binding and Adhesion. ChemistrySelect 2017. [DOI: 10.1002/slct.201701875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Madhuri Gade
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road Pune- 411008 India
| | - Preeti Madhukar Chaudhary
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road Pune- 411008 India
| | - Hirekodathakallu V. Thulasiram
- Chemical Biology Unit; Division of Organic Chemistry; CSIR-National chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
| | - Raghavendra Kikkeri
- Department of Chemistry; Indian Institute of Science Education and Research; Dr. Homi Bhabha Road Pune- 411008 India
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7
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Ghiselli G. Drug-Mediated Regulation of Glycosaminoglycan Biosynthesis. Med Res Rev 2016; 37:1051-1094. [DOI: 10.1002/med.21429] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 10/26/2016] [Accepted: 10/26/2016] [Indexed: 12/22/2022]
Affiliation(s)
- Giancarlo Ghiselli
- Glyconova Srl; Parco Scientifico Silvano Fumero; Via Ribes 5 Colleretto Giacosa, (TO) Italy
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Ghiselli G, Maccarana M. Drugs affecting glycosaminoglycan metabolism. Drug Discov Today 2016; 21:1162-9. [PMID: 27217160 DOI: 10.1016/j.drudis.2016.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 04/07/2016] [Accepted: 05/13/2016] [Indexed: 01/02/2023]
Abstract
Glycosaminoglycans (GAGs) are charged polysaccharides ubiquitously present at the cell surface and in the extracellular matrix. GAGs are crucial for cellular homeostasis, and their metabolism is altered during pathological processes. However, little consideration has been given to the regulation of the GAG milieu through pharmacological interventions. In this review, we provide a classification of small molecules affecting GAG metabolism based on their mechanism of action. Furthermore, we present evidence to show that clinically approved drugs affect GAG metabolism and that this could contribute to their therapeutic benefit.
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Affiliation(s)
- Giancarlo Ghiselli
- Glyconova Srl, Parco Scientifico Silvano Fumero, Via Ribes 5, 10010 Colleretto Giacosa (TO), Italy.
| | - Marco Maccarana
- Department of Experimental Medical Science, Biomedical Center C12, Lund University, Tornavägen 10, SE-221 84 Lund, Sweden
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Kiss L, Fülöp F. Synthesis of carbocyclic and heterocyclic β-aminocarboxylic acids. Chem Rev 2013; 114:1116-69. [PMID: 24299148 DOI: 10.1021/cr300454h] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Loránd Kiss
- Institute of Pharmaceutical Chemistry, University of Szeged , H-6720 Szeged, Eötvös utca 6, Hungary
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van Wijk XMR, van Kuppevelt TH. Heparan sulfate in angiogenesis: a target for therapy. Angiogenesis 2013; 17:443-62. [PMID: 24146040 DOI: 10.1007/s10456-013-9401-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 10/15/2013] [Indexed: 01/02/2023]
Abstract
Heparan sulfate (HS), a long linear polysaccharide of alternating disaccharide residues, interacts with a wide variety of proteins, including many angiogenic factors. The involvement of HS in signaling of pro-angiogenic factors (e.g. vascular endothelial growth factor and fibroblast growth factor 2), as well as interaction with anti-angiogenic factors (e.g. endostatin), warrants its role as an important modifier of (tumor) angiogenesis. This review summarizes our current understanding of the role of HS in angiogenic growth factor signaling, and discusses therapeutic strategies to target HS and modulate angiogenesis.
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Affiliation(s)
- Xander M R van Wijk
- Department of Biochemistry (280), Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, PO. Box 9101, 6500 HB, Nijmegen, The Netherlands
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Reddy BS, Reddy AB, Reddy GR, Reddy PR. Synthesis and Antibacterial Activity of Novel [3-(4-substitutedphenylamino)-8-azabicyclo [3.2.1] oct-8yl]-phenyl-methanone Derivatives. JOURNAL OF THE KOREAN CHEMICAL SOCIETY-DAEHAN HWAHAK HOE JEE 2011. [DOI: 10.5012/jkcs.2011.55.6.969] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Matsushima Y, Kino J. Synthesis ofN-Bz-Protected D-Daunosamine and D-Ristosamine by Silica Gel Promoted Intramolecular Conjugate Addition of Trichloroacetimidates obtained from Osmundalactone and Its Epimer. European J Org Chem 2010. [DOI: 10.1002/ejoc.200901402] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
BACKGROUND The guanidine group defines chemical and physicochemical properties of many compounds of medical interest and guanidine-containing derivatives constitute a very important class of therapeutic agents suitable for the treatment of a wide spectrum of diseases. OBJECTIVE To review the most important pharmacological properties, mechanisms of action and therapeutic uses of simple guanidine derivatives, cyclic analogues of guanidines as well as peptides, peptidomimetics and peptoids incorporating arginine. METHODS The review presents both the recent patent literature and original papers dealing with guanidine derivatives that show interesting biological activity and emphasizes the newest developing drugs. CONCLUSION Recent achievements in the synthesis of guanidine-containing molecules with diverse chemical, biochemical and pharmacological properties make them of great importance to the design and development of novel drugs acting at CNS, anti-inflammatory agents, inhibitors of Na(+)/H(+) exchanger, inhibitors of NO synthase, antithrombotic, antidiabetic and chemotherapeutic agents as well as guanidinium-based transporters and vectors.
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Affiliation(s)
- Franciszek Saczewski
- Department of Chemical Technology of Drugs, Medical University of Gdansk, Al. Gen. Hallera 107, Gdansk, Poland.
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14
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Kazi B, Kiss L, Forró E, Fülöp F. Synthesis of orthogonally protected azepane β-amino ester enantiomers. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2009.10.072] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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15
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Sánchez-Fernández EM, Rísquez-Cuadro R, Aguilar-Moncayo M, García-Moreno MI, Mellet CO, García Fernández JM. Generalized Anomeric Effect in gem-Diamines: Stereoselective Synthesis of α-N-Linked Disaccharide Mimics. Org Lett 2009; 11:3306-9. [DOI: 10.1021/ol901125n] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Elena M. Sánchez-Fernández
- Instituto de Investigaciones Químicas, CSIC and Universidad de Sevilla, Américo Vespucio 49, Isla de la Cartuja, E-41092 Sevilla, Spain, and Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apartado 1203, E-41071 Sevilla, Spain
| | - Rocío Rísquez-Cuadro
- Instituto de Investigaciones Químicas, CSIC and Universidad de Sevilla, Américo Vespucio 49, Isla de la Cartuja, E-41092 Sevilla, Spain, and Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apartado 1203, E-41071 Sevilla, Spain
| | - Matilde Aguilar-Moncayo
- Instituto de Investigaciones Químicas, CSIC and Universidad de Sevilla, Américo Vespucio 49, Isla de la Cartuja, E-41092 Sevilla, Spain, and Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apartado 1203, E-41071 Sevilla, Spain
| | - M. Isabel García-Moreno
- Instituto de Investigaciones Químicas, CSIC and Universidad de Sevilla, Américo Vespucio 49, Isla de la Cartuja, E-41092 Sevilla, Spain, and Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apartado 1203, E-41071 Sevilla, Spain
| | - Carmen Ortiz Mellet
- Instituto de Investigaciones Químicas, CSIC and Universidad de Sevilla, Américo Vespucio 49, Isla de la Cartuja, E-41092 Sevilla, Spain, and Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apartado 1203, E-41071 Sevilla, Spain
| | - José M. García Fernández
- Instituto de Investigaciones Químicas, CSIC and Universidad de Sevilla, Américo Vespucio 49, Isla de la Cartuja, E-41092 Sevilla, Spain, and Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla, Apartado 1203, E-41071 Sevilla, Spain
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Gem-diamine 1-N-iminosugars as versatile glycomimetics: synthesis, biological activity and therapeutic potential. J Antibiot (Tokyo) 2009; 62:407-23. [DOI: 10.1038/ja.2009.53] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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Polyoxometalates as effective inhibitors for sialyl- and sulfotransferases. J Inorg Biochem 2009; 103:1061-6. [PMID: 19508952 DOI: 10.1016/j.jinorgbio.2009.05.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Revised: 04/14/2009] [Accepted: 05/06/2009] [Indexed: 11/22/2022]
Abstract
Sialylated and/or sulfated carbohydrate chains in glycoproteins and glycolipids play important roles in infection by microorganisms and diseases including cancer. Inhibitors of sialyl/sulfotransferases, responsible for the biosynthesis of these carbohydrate chains, could be medical agents against such infections and diseases. Polyoxometalates (PMs) are inorganic polyanionic molecules that have been shown to exhibit activity against tumors and infectious microorganisms; however, the effects of PMs on carbohydrate biosynthesis have never been investigated. Here, we found that some types of PMs can inhibit the enzymatic activities of specific sialyl/sulfotransferases. Several tungstate-type PMs inhibited Gal: alpha2,3-sialyltransferase-I (ST3Gal-I) activity at sub-nanomolar levels. The half-inhibitory concentration of the best inhibitors was 0.2 nM and the inhibition was non-competitive for both donor and acceptor substrates (Ki values approximately 0.5 nM). By certain vanadate-type PMs, ST3Gal-I and Gal 3-O-sulfotransferase-2 (Gal3ST-2) were specifically inhibited at nanomolar levels. The inhibitory effect of a tungstate-type PM on ST3Gal-I was reversible and electrostatic. A ST3Gal-I mutant protein which was converted (335)Arg residue in the C-terminal region to Glu, was rather insensitive to the PM, suggesting that specific C-terminal basic amino acid of ST3Gal-I is involved in the binding to PMs. Collectively, PMs are novel inhibitors of specific sialyl/sulfotransferases.
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Matsushima Y, Kino J. New Concise Route to 2-Amino-3-hydroxycycloalkanecarboxylic Acids by Imidate-Mediated Intramolecular Conjugate Addition. European J Org Chem 2009. [DOI: 10.1002/ejoc.200801173] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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19
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Matsushima Y, Kino J. Intramolecular conjugate addition of γ- and δ-trichloroacetimidoyloxy-α,β-unsaturated esters in an acyclic system. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.02.061] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Brown JR, Crawford BE, Esko JD. Glycan antagonists and inhibitors: a fount for drug discovery. Crit Rev Biochem Mol Biol 2008; 42:481-515. [PMID: 18066955 DOI: 10.1080/10409230701751611] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Glycans, the carbohydrate chains of glycoproteins, proteoglycans, and glycolipids, represent a relatively unexploited area for drug development compared with other macromolecules. This review describes the major classes of glycans synthesized by animal cells, their mode of assembly, and available inhibitors for blocking their biosynthesis and function. Many of these agents have proven useful for studying the biological activities of glycans in isolated cells, during embryological development, and in physiology. Some are being used to develop drugs for treating metabolic disorders, cancer, and infection, suggesting that glycans are excellent targets for future drug development.
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A new strategy for the preparation of heterocyclic β-amino esters: orthogonally protected β-amino esters with a piperidine skeleton. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2007.11.043] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Argyropoulos NG, Panagiotidis T, Coutouli-Argyropoulou E, Raptopoulou C. Asymmetric nitrone cycloadditions and their application to the synthesis of enantiopure pyrrolidine and pyrrolizidine derivatives. Tetrahedron 2007. [DOI: 10.1016/j.tet.2006.10.076] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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23
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Matsushima Y, Kino J. An intramolecular conjugate addition of γ-trichloroacetimidoyloxy-α,β-unsaturated esters: a very concise route to daunosamine, acosamine, ristosamine and 3-epi-daunosamine precursors. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.09.164] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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