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Doyle LM, O'Sullivan S, Di Salvo C, McKinney M, McArdle P, Murphy PV. Stereoselective Epimerizations of Glycosyl Thiols. Org Lett 2018; 19:5802-5805. [PMID: 29039672 DOI: 10.1021/acs.orglett.7b02760] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Glycosyl thiols are widely used in stereoselective S-glycoside synthesis. Their epimerization from 1,2-trans to 1,2-cis thiols (e.g., equatorial to axial epimerization in thioglucopyranose) was attained using TiCl4, while SnCl4 promoted their axial-to-equatorial epimerization. The method included application for stereoselective β-d-manno- and β-l-rhamnopyranosyl thiol formation. Complex formation explains the equatorial preference when using SnCl4, whereas TiCl4 can shift the equilibrium toward the 1,2-cis thiol via 1,3-oxathiolane formation.
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Affiliation(s)
- Lisa M Doyle
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland H91 TK33
| | - Shane O'Sullivan
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland H91 TK33
| | - Claudia Di Salvo
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland H91 TK33
| | - Michelle McKinney
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland H91 TK33
| | - Patrick McArdle
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland H91 TK33
| | - Paul V Murphy
- School of Chemistry, National University of Ireland Galway , University Road, Galway, Ireland H91 TK33
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2
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Padiyar LT, Zulueta MML, Sabbavarapu NM, Hung SC. Yb(OTf) 3-Catalyzed Desymmetrization of myo-Inositol 1,3,5-Orthoformate and Its Application in the Synthesis of Chiral Inositol Phosphates. J Org Chem 2017; 82:11418-11430. [PMID: 29019688 DOI: 10.1021/acs.joc.7b01919] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A variety of inositol phosphates including myo-inositol 1,4,5-trisphosphate, which is a secondary messenger in transmembrane signaling, were selectively synthesized via Yb(OTf)3-catalyzed desymmetrization of myo-inositol 1,3,5-orthoformate using a proline-based chiral anhydride as an acylation precursor. The investigated catalytic system could regioselectively differentiate the enantiotopic hydroxy groups of myo-inositol 1,3,5-orthoformate in the presence of a chiral auxiliary. This key step to generate a suitably protected chiral myo-inositol derivatives is described here as a unified approach to access inositol phosphates.
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Affiliation(s)
- Laxmansingh T Padiyar
- Genomics Research Center, Academia Sinica , 128 Section 2 Academia Road, Taipei 115, Taiwan
| | - Medel Manuel L Zulueta
- Genomics Research Center, Academia Sinica , 128 Section 2 Academia Road, Taipei 115, Taiwan
| | | | - Shang-Cheng Hung
- Genomics Research Center, Academia Sinica , 128 Section 2 Academia Road, Taipei 115, Taiwan
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3
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Inositol polyphosphates intersect with signaling and metabolic networks via two distinct mechanisms. Proc Natl Acad Sci U S A 2016; 113:E6757-E6765. [PMID: 27791083 DOI: 10.1073/pnas.1606853113] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Inositol-based signaling molecules are central eukaryotic messengers and include the highly phosphorylated, diffusible inositol polyphosphates (InsPs) and inositol pyrophosphates (PP-InsPs). Despite the essential cellular regulatory functions of InsPs and PP-InsPs (including telomere maintenance, phosphate sensing, cell migration, and insulin secretion), the majority of their protein targets remain unknown. Here, the development of InsP and PP-InsP affinity reagents is described to comprehensively annotate the interactome of these messenger molecules. By using the reagents as bait, >150 putative protein targets were discovered from a eukaryotic cell lysate (Saccharomyces cerevisiae). Gene Ontology analysis of the binding partners revealed a significant overrepresentation of proteins involved in nucleotide metabolism, glucose metabolism, ribosome biogenesis, and phosphorylation-based signal transduction pathways. Notably, we isolated and characterized additional substrates of protein pyrophosphorylation, a unique posttranslational modification mediated by the PP-InsPs. Our findings not only demonstrate that the PP-InsPs provide a central line of communication between signaling and metabolic networks, but also highlight the unusual ability of these molecules to access two distinct modes of action.
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4
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A Small Molecule Inhibitor of PDK1/PLCγ1 Interaction Blocks Breast and Melanoma Cancer Cell Invasion. Sci Rep 2016; 6:26142. [PMID: 27199173 PMCID: PMC4873738 DOI: 10.1038/srep26142] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 04/21/2016] [Indexed: 12/02/2022] Open
Abstract
Strong evidence suggests that phospholipase Cγ1 (PLCγ1) is a suitable target to counteract tumourigenesis and metastasis dissemination. We recently identified a novel signalling pathway required for PLCγ1 activation which involves formation of a protein complex with 3-phosphoinositide-dependent protein kinase 1 (PDK1). In an effort to define novel strategies to inhibit PLCγ1-dependent signals we tested here whether a newly identified and highly specific PDK1 inhibitor, 2-O-benzyl-myo-inositol 1,3,4,5,6-pentakisphosphate (2-O-Bn-InsP5), could affect PDK1/PLCγ1 interaction and impair PLCγ1-dependent cellular functions in cancer cells. Here, we demonstrate that 2-O-Bn-InsP5 interacts specifically with the pleckstrin homology domain of PDK1 and impairs formation of a PDK1/PLCγ1 complex. 2-O-Bn-InsP5 is able to inhibit the epidermal growth factor-induced PLCγ1 phosphorylation and activity, ultimately resulting in impaired cancer cell migration and invasion. Importantly, we report that 2-O-Bn-InsP5 inhibits cancer cell dissemination in zebrafish xenotransplants. This work demonstrates that the PDK1/PLCγ1 complex is a potential therapeutic target to prevent metastasis and it identifies 2-O-Bn-InsP5 as a leading compound for development of anti-metastatic drugs.
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5
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Thomas MP, Mills SJ, Potter BVL. The "Other" Inositols and Their Phosphates: Synthesis, Biology, and Medicine (with Recent Advances in myo-Inositol Chemistry). Angew Chem Int Ed Engl 2016; 55:1614-50. [PMID: 26694856 PMCID: PMC5156312 DOI: 10.1002/anie.201502227] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Indexed: 12/24/2022]
Abstract
Cell signaling via inositol phosphates, in particular via the second messenger myo-inositol 1,4,5-trisphosphate, and phosphoinositides comprises a huge field of biology. Of the nine 1,2,3,4,5,6-cyclohexanehexol isomers, myo-inositol is pre-eminent, with "other" inositols (cis-, epi-, allo-, muco-, neo-, L-chiro-, D-chiro-, and scyllo-) and derivatives rarer or thought not to exist in nature. However, neo- and d-chiro-inositol hexakisphosphates were recently revealed in both terrestrial and aquatic ecosystems, thus highlighting the paucity of knowledge of the origins and potential biological functions of such stereoisomers, a prevalent group of environmental organic phosphates, and their parent inositols. Some "other" inositols are medically relevant, for example, scyllo-inositol (neurodegenerative diseases) and d-chiro-inositol (diabetes). It is timely to consider exploration of the roles and applications of the "other" isomers and their derivatives, likely by exploiting techniques now well developed for the myo series.
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Affiliation(s)
- Mark P Thomas
- Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Stephen J Mills
- Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Barry V L Potter
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK.
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6
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Pavlovic I, Thakor DT, Jessen HJ. Synthesis of 2-diphospho-myo-inositol 1,3,4,5,6-pentakisphosphate and a photocaged analogue. Org Biomol Chem 2016; 14:5559-62. [DOI: 10.1039/c6ob00094k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Diphosphoinositol polyphosphates (inositol pyrophosphates, X-InsP7) are a family of second messengers with important roles in eukaryotic biology. A new approach targeting 2-InsP7 and a photocaged analogue is described.
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Affiliation(s)
- I. Pavlovic
- Department of Chemistry
- University of Zürich
- 8057 Zürich
- Switzerland
| | - D. T. Thakor
- Department of Chemistry
- University of Zürich
- 8057 Zürich
- Switzerland
| | - H. J. Jessen
- Department of Chemistry and Pharmacy
- Albert-Ludwigs University Freiburg
- 79104 Freiburg
- Germany
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7
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Thomas MP, Mills SJ, Potter BVL. Die “anderen” Inositole und ihre Phosphate: Synthese, Biologie und Medizin (sowie jüngste Fortschritte in dermyo-Inositolchemie). Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201502227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Mark P. Thomas
- Department of Pharmacy & Pharmacology; University of Bath; Claverton Down Bath BA2 7AY Vereinigtes Königreich
| | - Stephen J. Mills
- Department of Pharmacy & Pharmacology; University of Bath; Claverton Down Bath BA2 7AY Vereinigtes Königreich
| | - Barry V. L. Potter
- Department of Pharmacology; University of Oxford; Mansfield Road Oxford OX1 3QT Vereinigtes Königreich
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8
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Frihed TG, Bols M, Pedersen CM. Mechanisms of Glycosylation Reactions Studied by Low-Temperature Nuclear Magnetic Resonance. Chem Rev 2015; 115:4963-5013. [DOI: 10.1021/cr500434x] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
| | - Mikael Bols
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
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9
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Wang H, Godage HY, Riley AM, Weaver JD, Shears SB, Potter BVL. Synthetic inositol phosphate analogs reveal that PPIP5K2 has a surface-mounted substrate capture site that is a target for drug discovery. ACTA ACUST UNITED AC 2014; 21:689-99. [PMID: 24768307 PMCID: PMC4085797 DOI: 10.1016/j.chembiol.2014.03.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 02/28/2014] [Accepted: 03/17/2014] [Indexed: 11/17/2022]
Abstract
Diphosphoinositol pentakisphosphate kinase 2 (PPIP5K2) is one of the mammalian PPIP5K isoforms responsible for synthesis of diphosphoinositol polyphosphates (inositol pyrophosphates; PP-InsPs), regulatory molecules that function at the interface of cell signaling and organismic homeostasis. The development of drugs that inhibit PPIP5K2 could have both experimental and therapeutic applications. Here, we describe a synthetic strategy for producing naturally occurring 5-PP-InsP4, as well as several inositol polyphosphate analogs, and we study their interactions with PPIP5K2 using biochemical and structural approaches. These experiments uncover an additional ligand-binding site on the surface of PPIP5K2, adjacent to the catalytic pocket. This site facilitates substrate capture from the bulk phase, prior to transfer into the catalytic pocket. In addition to demonstrating a “catch-and-pass” reaction mechanism in a small molecule kinase, we demonstrate that binding of our analogs to the substrate capture site inhibits PPIP5K2. This work suggests that the substrate-binding site offers new opportunities for targeted drug design. Chemical synthesis of 5-PP-InsP4 and a diphosphorylated analog Chemical synthesis of inositol polyphosphate analogs with hydrophobic groups An inositol pyrophosphate kinase has a surface-mounted, substrate capture site Structural and biochemical characterization of a catch-and-pass catalytic cycle
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Affiliation(s)
- Huanchen Wang
- Inositol Signaling Group, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Himali Y Godage
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, Somerset BA2 7AY, UK
| | - Andrew M Riley
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, Somerset BA2 7AY, UK
| | - Jeremy D Weaver
- Inositol Signaling Group, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Stephen B Shears
- Inositol Signaling Group, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA.
| | - Barry V L Potter
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, Somerset BA2 7AY, UK.
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10
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Capolicchio S, Thakor DT, Linden A, Jessen HJ. Synthesis of unsymmetric diphospho-inositol polyphosphates. Angew Chem Int Ed Engl 2013; 52:6912-6. [PMID: 23712702 DOI: 10.1002/anie.201301092] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 03/29/2013] [Indexed: 11/05/2022]
Affiliation(s)
- Samanta Capolicchio
- Organic Chemistry Institute, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
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11
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Capolicchio S, Thakor DT, Linden A, Jessen HJ. Synthesis of Unsymmetric Diphospho-Inositol Polyphosphates. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201301092] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Godage H, Riley AM, Woodman TJ, Thomas MP, Mahon MF, Potter BVL. Regioselective opening of myo-inositol orthoesters: mechanism and synthetic utility. J Org Chem 2013; 78:2275-88. [PMID: 23438216 PMCID: PMC3601604 DOI: 10.1021/jo3027774] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Indexed: 01/06/2023]
Abstract
Acid hydrolysis of myo-inositol 1,3,5-orthoesters, apart from orthoformates, exclusively affords the corresponding 2-O-acyl myo-inositol products via a 1,2-bridged five-membered ring dioxolanylium ion intermediate observed by NMR spectroscopy. These C-2-substituted inositol derivatives provide valuable precursors for rapid and highly efficient routes to 2-O-acyl inositol 1,3,4,5,6-pentakisphosphates and myo-inositol 1,3,4,5,6-pentakisphosphate with biologically interesting and anticancer properties. Deuterium incorporation into the α-methylene group of such alkyl ester products (2-O-C(O)CD2R), when the analogous alkyl orthoester is treated with deuterated acid, is established utilizing the novel orthoester myo-inositol 1,3,5-orthobutyrate as an example. Such deuterated ester products provide intermediates for deuterium-labeled synthetic analogues. Investigation into this selective formation of 2-O-ester products and the deuterium incorporation is presented with proposed mechanisms from NMR experiments.
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Affiliation(s)
- Himali
Y. Godage
- Wolfson
Laboratory of Medicinal Chemistry, Department of Pharmacy
and Pharmacology, X-ray
Crystallographic Suite, Department of Chemistry, University of Bath, Bath BA2 7AY, U.K
| | - Andrew M. Riley
- Wolfson
Laboratory of Medicinal Chemistry, Department of Pharmacy
and Pharmacology, X-ray
Crystallographic Suite, Department of Chemistry, University of Bath, Bath BA2 7AY, U.K
| | - Timothy J. Woodman
- Wolfson
Laboratory of Medicinal Chemistry, Department of Pharmacy
and Pharmacology, X-ray
Crystallographic Suite, Department of Chemistry, University of Bath, Bath BA2 7AY, U.K
| | - Mark P. Thomas
- Wolfson
Laboratory of Medicinal Chemistry, Department of Pharmacy
and Pharmacology, X-ray
Crystallographic Suite, Department of Chemistry, University of Bath, Bath BA2 7AY, U.K
| | - Mary F. Mahon
- Wolfson
Laboratory of Medicinal Chemistry, Department of Pharmacy
and Pharmacology, X-ray
Crystallographic Suite, Department of Chemistry, University of Bath, Bath BA2 7AY, U.K
| | - Barry V. L. Potter
- Wolfson
Laboratory of Medicinal Chemistry, Department of Pharmacy
and Pharmacology, X-ray
Crystallographic Suite, Department of Chemistry, University of Bath, Bath BA2 7AY, U.K
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13
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Vidyasagar A, Pathigoolla A, Sureshan KM. Chemoselective alcoholysis/acetolysis of trans-ketals over cis-ketals and its application in the total synthesis of the cellular second messenger, d-myo-inositol-1,4,5-trisphosphate. Org Biomol Chem 2013; 11:5443-53. [DOI: 10.1039/c3ob40789f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Adiyala Vidyasagar
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram 695016, India
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Vibhute AM, Sureshan KM. H2SO4-silica: an eco-friendly heterogeneous catalyst for the differential protection of myo-inositol hydroxyl groups. RSC Adv 2013. [DOI: 10.1039/c3ra40506k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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15
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Wu M, Dul BE, Trevisan AJ, Fiedler D. Synthesis and characterization of non-hydrolysable diphosphoinositol polyphosphate second messengers. Chem Sci 2013; 4:405-410. [PMID: 23378892 DOI: 10.1039/c2sc21553e] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The diphosphoinositol polyphosphates (PP-IPs) are a central group of eukaryotic second messengers. They regulate numerous processes, including cellular energy homeostasis and adaptation to environmental stresses. To date, most of the molecular details in PP-IP signalling have remained elusive, due to a lack of appropriate methods and reagents. Here we describe the expedient synthesis of methylene-bisphosphonate PP-IP analogues. Their characterization revealed that the analogues exhibit significant stability and mimic their natural counterparts very well. This was further confirmed in two independent biochemical assays, in which our analogues potently inhibited phosphorylation of the protein kinase Akt and hydrolytic activity of the Ddp1 phosphohydrolase. The non-hydrolysable PP-IPs thus emerge as important tools and hold great promise for a variety of applications.
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Affiliation(s)
- Mingxuan Wu
- Department of Chemistry, Princeton University, Washington Rd., 85 Princeton, NJ, 08544, USA. Tel: +1 609 258 1025
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Mart A, Shashidhar MS. Elaboration of the ether cleaving ability and selectivity of the classical Pearlman's catalyst [Pd(OH)2/C]: concise synthesis of a precursor for a myo-inositol pyrophosphate. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.09.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Manoel EA, Pais KC, Cunha AG, Coelho MAZ, Freire DM, Simas AB. On the kinetic resolution of sterically hindered myo-inositol derivatives in organic media by lipases. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.tetasy.2012.01.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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18
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Vibhute AM, Vidyasagar A, Sarala S, Sureshan KM. Regioselectivity among six secondary hydroxyl groups: selective acylation of the least reactive hydroxyl groups of inositol. Chem Commun (Camb) 2012; 48:2448-50. [DOI: 10.1039/c2cc17241k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Falasca M, Chiozzotto D, Godage HY, Mazzoletti M, Riley AM, Previdi S, Potter BVL, Broggini M, Maffucci T. A novel inhibitor of the PI3K/Akt pathway based on the structure of inositol 1,3,4,5,6-pentakisphosphate. Br J Cancer 2010; 102:104-14. [PMID: 20051961 PMCID: PMC2813745 DOI: 10.1038/sj.bjc.6605408] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Owing to its role in cancer, the phosphoinositide 3-kinase (PI3K)/Akt pathway is an attractive target for therapeutic intervention. We previously reported that the inhibition of Akt by inositol 1,3,4,5,6-pentakisphosphate (InsP(5)) results in anti-tumour properties. To further develop this compound we modified its structure to obtain more potent inhibitors of the PI3K/Akt pathway. METHODS Cell proliferation/survival was determined by cell counting, sulphorhodamine or acridine orange/ethidium bromide assay; Akt activation was determined by western blot analysis. In vivo effect of compounds was tested on PC3 xenografts, whereas in vitro activity on kinases was determined by SelectScreen Kinase Profiling Service. RESULTS The derivative 2-O-benzyl-myo-inositol 1,3,4,5,6-pentakisphosphate (2-O-Bn-InsP(5)) is active towards cancer types resistant to InsP(5) in vitro and in vivo. 2-O-Bn-InsP(5) possesses higher pro-apoptotic activity than InsP(5) in sensitive cells and enhances the effect of anti-cancer compounds. 2-O-Bn-InsP(5) specifically inhibits 3-phosphoinositide-dependent protein kinase 1 (PDK1) in vitro (IC(50) in the low nanomolar range) and the PDK1-dependent phosphorylation of Akt in cell lines and excised tumours. It is interesting to note that 2-O-Bn-InsP(5) also inhibits the mammalian target of rapamycin (mTOR) in vitro. CONCLUSIONS InsP(5) and 2-O-Bn-InsP(5) may represent lead compounds to develop novel inhibitors of the PI3K/Akt pathway (including potential dual PDK1/mTOR inhibitors) and novel potential anti-cancer drugs.
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Affiliation(s)
- M Falasca
- Queen Mary University of London, Barts and The London School of Medicine and Dentistry, Blizard Institute of Cell and Molecular Science, Centre for Diabetes, Inositide Signalling Group, 4 Newark Street, London E1 2AT, UK.
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Murali C, Gurale BP, Shashidhar MS. Intramolecular Hydrogen Abstraction in Radicals Derived from Inositol 1,3-Acetals: Efficient Access to Cyclitols. European J Org Chem 2010. [DOI: 10.1002/ejoc.200901156] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Best MD, Zhang H, Prestwich GD. Inositol polyphosphates, diphosphoinositol polyphosphates and phosphatidylinositol polyphosphate lipids: Structure, synthesis, and development of probes for studying biological activity. Nat Prod Rep 2010; 27:1403-30. [DOI: 10.1039/b923844c] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Devaraj S, Jagdhane RC, Shashidhar MS. Relative reactivity of hydroxyl groups in inositol derivatives: role of metal ion chelation. Carbohydr Res 2009; 344:1159-66. [DOI: 10.1016/j.carres.2009.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 04/04/2009] [Accepted: 04/09/2009] [Indexed: 10/20/2022]
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24
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The behaviour of inositol 1,3,4,5,6-pentakisphosphate in the presence of the major biological metal cations. J Biol Inorg Chem 2009; 14:1001-13. [PMID: 19415348 PMCID: PMC2745655 DOI: 10.1007/s00775-009-0510-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Accepted: 04/20/2009] [Indexed: 01/07/2023]
Abstract
The inositol phosphates are ubiquitous metabolites in eukaryotes, of which the most abundant are inositol hexakisphosphate (InsP 6) and inositol 1,3,4,5,6-pentakisphosphate [Ins(1,3,4,5,6)P5)]. These two compounds, poorly understood functionally, have complicated complexation and solid formation behaviours with multivalent cations. For InsP 6, we have previously described this chemistry and its biological implications (Veiga et al. in J Inorg Biochem 100:1800, 2006; Torres et al. in J Inorg Biochem 99:828, 2005). We now cover similar ground for Ins(1,3,4,5,6)P5, describing its interactions in solution with Na+, K+, Mg2+, Ca2+, Cu2+, Fe2+ and Fe3+, and its solid-formation equilibria with Ca2+ and Mg2+. Ins(1,3,4,5,6)P5 forms soluble complexes of 1:1 stoichiometry with all multivalent cations studied. The affinity for Fe3+ is similar to that of InsP6 and inositol 1,2,3-trisphosphate, indicating that the 1,2,3-trisphosphate motif, which Ins(1,3,4,5,6)P5 lacks, is not absolutely necessary for high-affinity Fe3+ complexation by inositol phosphates, even if it is necessary for their prevention of the Fenton reaction. With excess Ca2+ and Mg2+, Ins(1,3,4,5,6)P5 also forms the polymetallic complexes [M4(H2L)] [where L is fully deprotonated Ins(1,3,4,5,6)P5]. However, unlike InsP6, Ins(1,3,4,5,6)P5 is predicted not to be fully associated with Mg2+ under simulated cytosolic/nuclear conditions. The neutral Mg2+ and Ca2+ complexes have significant windows of solubility, but they precipitate as [Mg4(H2L)] x 23H2O or [Ca4(H2L)] x 16H2O whenever they exceed 135 and 56 microM in concentration, respectively. Nonetheless, the low stability of the [M4(H2L)] complexes means that the 1:1 species contribute to the overall solubility of Ins(1,3,4,5,6)P 5 even under significant Mg2+ or Ca2+ excesses. We summarize the solubility behaviour of Ins(1,3,4,5,6)P5 in straightforward plots.
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Sureshan KM, Riley AM, Potter BV. Rapid and efficient routes to phosphatidylinositol 3,4,5-trisphosphates via myo-inositol orthobenzoate. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.01.095] [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]
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