1
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Ismatullah H, Jabeen I, Kiani YS. Structural and functional insight into a new emerging target IP 3R in cancer. J Biomol Struct Dyn 2024; 42:2170-2196. [PMID: 37070253 DOI: 10.1080/07391102.2023.2201332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 04/05/2023] [Indexed: 04/19/2023]
Abstract
Calcium signaling has been identified as an important phenomenon in a plethora of cellular processes. Inositol 1,4,5-trisphosphate receptors (IP3Rs) are ER-residing intracellular calcium (Ca2+) release channels responsible for cell bioenergetics by transferring calcium from the ER to the mitochondria. The recent availability of full-length IP3R channel structure has enabled the researchers to design the IP3 competitive ligands and reveal the channel gating mechanism by elucidating the conformational changes induced by ligands. However, limited knowledge is available for IP3R antagonists and the exact mechanism of action of these antagonists within a tumorigenic environment of a cell. Here in this review a summarized information about the role of IP3R in cell proliferation and apoptosis has been discussed. Moreover, structure and gating mechanism of IP3R in the presence of antagonists have been provided in this review. Additionally, compelling information about ligand-based studies (both agonists and antagonists) has been discussed. The shortcomings of these studies and the challenges toward the design of potent IP3R modulators have also been provided in this review. However, the conformational changes induced by antagonists for channel gating mechanism still display some major drawbacks that need to be addressed. However, the design, synthesis and availability of isoform-specific antagonists is a rather challenging one due to intra-structural similarity within the binding domain of each isoform. HighlightsThe intricate complexity of IP3R's in cellular processes declares them an important target whereby, the recently solved structure depicts the receptor's potential involvement in a complex network of processes spanning from cell proliferation to cell death.Pharmacological inhibition of IP3R attenuates the proliferation or invasiveness of cancers, thus inducing necrotic cell death.Despite significant advancements, there is a tremendous need to design new potential hits to target IP3R, based upon 3D structural features and pharmacophoric patterns.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Humaira Ismatullah
- Department of Sciences, School of Interdisciplinary Engineering and Sciences (SINES), National University of Sciences and Technology (NUST), Islamabad, Pakistan
| | - Ishrat Jabeen
- Department of Sciences, School of Interdisciplinary Engineering and Sciences (SINES), National University of Sciences and Technology (NUST), Islamabad, Pakistan
| | - Yusra Sajid Kiani
- Department of Sciences, School of Interdisciplinary Engineering and Sciences (SINES), National University of Sciences and Technology (NUST), Islamabad, Pakistan
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2
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Kennett A, Epple S, van der Valk G, Georgiou I, Gout E, Vivès RR, Russell AJ. Modified minimal-size fragments of heparan sulfate as inhibitors of endosulfatase-2 (Sulf-2). Chem Commun (Camb) 2024; 60:436-439. [PMID: 38086706 DOI: 10.1039/d3cc02565a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Sulf-2 has been identified as a putative target for anticancer therapies. Here we report the design and synthesis of sulfated disaccharide inhibitors based on IdoA(2S)-GlcNS(6S). Trisulfated disaccharide inhibitor IdoA(2S)-GlcNS(6Sulfamate) demonstrated potent Sulf-2 inhibition. The IC50 value was determined to be 39.8 μM ± 18.3, which is comparable to a tetrasaccharide inhibitor of HSulf-1 reported in the literature. We propose that the disaccharide IdoA(2S)-GlcNS(6S) is the shortest fragment size required for effective inhibition of the Sulfs.
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Affiliation(s)
- Alice Kennett
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK.
| | - Sven Epple
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK.
| | | | - Irene Georgiou
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK.
| | - Evelyne Gout
- Univ. Grenoble Alpes, CNRS, CEA, IBS, Grenoble, France
| | | | - Angela J Russell
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK.
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
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3
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Della-Felice F, de Andrade Bartolomeu A, Pilli RA. The phosphate ester group in secondary metabolites. Nat Prod Rep 2022; 39:1066-1107. [PMID: 35420073 DOI: 10.1039/d1np00078k] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Covering: 2000 to mid-2021The phosphate ester is a versatile, widespread functional group involved in a plethora of biological activities. Its presence in secondary metabolites, however, is relatively rare compared to other functionalities and thus is part of a rather unexplored chemical space. Herein, the chemistry of secondary metabolites containing the phosphate ester group is discussed. The text emphasizes their structural diversity, biological and pharmacological profiles, and synthetic approaches employed in the phosphorylation step during total synthesis campaigns, covering the literature from 2000 to mid-2021.
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Affiliation(s)
- Franco Della-Felice
- Institute of Chemistry, University of Campinas (UNICAMP), P.O. Box 6154, CEP 13083-970 Campinas, Sao Paulo, Brazil.,Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain.
| | | | - Ronaldo Aloise Pilli
- Institute of Chemistry, University of Campinas (UNICAMP), P.O. Box 6154, CEP 13083-970 Campinas, Sao Paulo, Brazil
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4
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Gambardella J, Morelli MB, Wang X, Castellanos V, Mone P, Santulli G. The discovery and development of IP3 receptor modulators: an update. Expert Opin Drug Discov 2021; 16:709-718. [PMID: 33356639 DOI: 10.1080/17460441.2021.1858792] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Introduction: Inositol 1,4,5-trisphosphate receptors (IP3Rs) are intracellular calcium (Ca2+) release channels located on the endoplasmic/sarcoplasmic reticulum. The availability of the structure of the ligand-binding domain of IP3Rs has enabled the design of compatible ligands, but the limiting step remains their actual effectiveness in a biological context.Areas covered: This article summarizes the compelling literature on both agonists and antagonists targeting IP3Rs, emphasizing their strengths and limitations. The main challenges toward the discovery and development of IP3 receptor modulators are also described.Expert opinion: Despite significant progress in recent years, the pharmacology of IP3R still has major drawbacks, especially concerning the availability of specific antag onists. Moreover, drugs specifically targeting the three different subtypes of IP3R are especially needed.
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Affiliation(s)
- Jessica Gambardella
- Department of Medicine (Division of Cardiology), Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, Montefiore University Hospital, New York City, USA.,Department of Molecular Pharmacology, Fleischer Institute for Diabetes and Metabolism, Einstein-Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York City, USA.,Department of Advanced Biomedical Sciences, "Federico II" University, Naples, Italy.,International Translational Research and Medical Education (ITME), Naples, Italy
| | - Marco B Morelli
- Department of Medicine (Division of Cardiology), Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, Montefiore University Hospital, New York City, USA.,Department of Molecular Pharmacology, Fleischer Institute for Diabetes and Metabolism, Einstein-Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York City, USA
| | - Xujun Wang
- Department of Medicine (Division of Cardiology), Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, Montefiore University Hospital, New York City, USA
| | - Vanessa Castellanos
- Department of Medicine (Division of Cardiology), Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, Montefiore University Hospital, New York City, USA
| | - Pasquale Mone
- University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Gaetano Santulli
- Department of Medicine (Division of Cardiology), Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, Montefiore University Hospital, New York City, USA.,Department of Molecular Pharmacology, Fleischer Institute for Diabetes and Metabolism, Einstein-Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York City, USA.,Department of Advanced Biomedical Sciences, "Federico II" University, Naples, Italy.,International Translational Research and Medical Education (ITME), Naples, Italy
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5
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Su X, Dohle W, Mills SJ, Watt JM, Rossi AM, Taylor CW, Potter BVL. Inositol Adenophostin: Convergent Synthesis of a Potent Agonist of d- myo-Inositol 1,4,5-Trisphosphate Receptors. ACS OMEGA 2020; 5:28793-28811. [PMID: 33195933 PMCID: PMC7659177 DOI: 10.1021/acsomega.0c04145] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 10/08/2020] [Indexed: 06/11/2023]
Abstract
d-myo-Inositol 1,4,5-trisphosphate receptors (IP3Rs) are Ca2+ channels activated by the intracellular messenger inositol 1,4,5-trisphosphate (IP3, 1). The glyconucleotide adenophostin A (AdA, 2) is a potent agonist of IP3Rs. A recent synthesis of d-chiro-inositol adenophostin (InsAdA, 5) employed suitably protected chiral building blocks and replaced the d-glucose core by d-chiro-inositol. An alternative approach to fully chiral material is now reported using intrinsic sugar chirality to avoid early isomer resolution, involving the coupling of a protected and activated racemic myo-inositol derivative to a d-ribose derivative. Diastereoisomer separation was achieved after trans-isopropylidene group removal and the absolute ribose-inositol conjugate stereochemistry assigned with reference to the earlier synthesis. Optimization of stannylene-mediated regiospecific benzylation was explored using the model 1,2-O-isopropylidene-3,6-di-O-benzyl-myo-inositol and conditions successfully transferred to one conjugate diastereoisomer with 3:1 selectivity. However, only roughly 1:1 regiospecificity was achieved on the required diastereoisomer. The conjugate regioisomers of benzyl derivatives 39 and 40 were successfully separated and 39 was transformed subsequently to InsAdA after amination, pan-phosphorylation, and deprotection. InsAdA from this synthetic route bound with greater affinity than AdA to IP3R1 and was more potent in releasing Ca2+ from intracellular stores through IP3Rs. It is the most potent full agonist of IP3R1 known and .equipotent with material from the fully chiral synthetic route.
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Affiliation(s)
- Xiangdong Su
- Medicinal
Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, U.K.
| | - Wolfgang Dohle
- Medicinal
Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, U.K.
| | - Stephen J. Mills
- Medicinal
Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, U.K.
| | - Joanna M. Watt
- Medicinal
Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, U.K.
- Wolfson
Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
| | - Ana M. Rossi
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K.
| | - Colin W. Taylor
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U.K.
| | - Barry V. L. Potter
- Medicinal
Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, U.K.
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6
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Shipton ML, Riley AM, Rossi AM, Brearley CA, Taylor CW, Potter BVL. Both d- and l-Glucose Polyphosphates Mimic d- myo-Inositol 1,4,5-Trisphosphate: New Synthetic Agonists and Partial Agonists at the Ins(1,4,5)P 3 Receptor. J Med Chem 2020; 63:5442-5457. [PMID: 32286062 PMCID: PMC7260056 DOI: 10.1021/acs.jmedchem.0c00215] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
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Chiral sugar derivatives are potential
cyclitol surrogates of the
Ca2+-mobilizing intracellular messenger d-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3]. Six novel polyphosphorylated analogues derived from both d- and l-glucose were synthesized. Binding to Ins(1,4,5)P3 receptors [Ins(1,4,5)P3R] and the ability to release
Ca2+ from intracellular stores via type 1 Ins(1,4,5)P3Rs were investigated. β-d-Glucopyranosyl 1,3,4-tris-phosphate,
with similar phosphate regiochemistry and stereochemistry to Ins(1,4,5)P3, and α-d-glucopyranosyl 1,3,4-tris-phosphate
are full agonists, being equipotent and 23-fold less potent than Ins(1,4,5)P3, respectively, in Ca2+-release assays and similar
to Ins(1,4,5)P3 and 15-fold weaker in binding assays. They
can be viewed as truncated analogues of adenophostin A and refine
understanding of structure-activity relationships for this Ins(1,4,5)P3R agonist. l-Glucose-derived ligands, methyl α-l-glucopyranoside 2,3,6-trisphosphate and methyl α-l-glucopyranoside 2,4,6-trisphosphate, are also active, while
their corresponding d-enantiomers, methyl α-d-glucopyranoside 2,3,6-trisphosphate and methyl α-d-glucopyranoside 2,4,6-trisphosphate, are inactive. Interestingly,
both l-glucose-derived ligands are partial agonists: they
are among the least efficacious agonists of Ins(1,4,5)P3R yet identified, providing new leads for antagonist development.
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Affiliation(s)
- Megan L Shipton
- Drug Discovery & Medicinal Chemistry, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, U. K
| | - Andrew M Riley
- Drug Discovery & Medicinal Chemistry, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, U. K
| | - Ana M Rossi
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U. K
| | - Charles A Brearley
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, U. K
| | - Colin W Taylor
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, U. K
| | - Barry V L Potter
- Drug Discovery & Medicinal Chemistry, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, U. K
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7
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Mills SJ, Rossi AM, Konieczny V, Bakowski D, Taylor CW, Potter BVL. d- chiro-Inositol Ribophostin: A Highly Potent Agonist of d- myo-Inositol 1,4,5-Trisphosphate Receptors: Synthesis and Biological Activities. J Med Chem 2020; 63:3238-3251. [PMID: 32052631 PMCID: PMC7104261 DOI: 10.1021/acs.jmedchem.9b01986] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Analogues
of the Ca2+-releasing intracellular messenger d-myo-inositol 1,4,5-trisphosphate [1, Ins(1,4,5)P3] are important synthetic targets. Replacement
of the α-glucopyranosyl motif in the natural product mimic adenophostin 2 by d-chiro-inositol in d-chiro-inositol adenophostin 4 increased
the potency. Similar modification of the non-nucleotide Ins(1,4,5)P3 mimic ribophostin 6 may increase the activity. d-chiro-Inositol ribophostin 10 was synthesized by coupling as building blocks suitably protected
ribose 12 with l-(+)-3-O-trifluoromethylsulfonyl-6-O-p-methoxybenzyl-1,2:4,5-di-O-isopropylidene-myo-inositol 11. Separable
diastereoisomeric 3-O-camphanate esters of (±)-6-O-p-methoxy-benzyl-1,2:4,5-di-O-isopropylidene-myo-inositol allowed the preparation
of 11. Selective trans-isopropylidene
deprotection in coupled 13, then monobenzylation gave
separable regioisomers 15 and 16. p-Methoxybenzyl group deprotection of 16, phosphitylation/oxidation,
then deprotection afforded 10, which was a full agonist
in Ca2+-release assays; its potency and binding affinity
for Ins(1,4,5)P3R were similar to those of adenophostin.
Both 4 and 10 elicited a store-operated
Ca2+ current ICRAC in patch-clamped cells, unlike
Ins(1,4,5)P3 consistent with resistance to metabolism. d-chiro-Inositol ribophostin is the most potent
small-molecule Ins(1,4,5)P3 receptor agonist without a
nucleobase yet synthesized.
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Affiliation(s)
- Stephen J Mills
- Drug Discovery & Medicinal Chemistry, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
| | - Ana M Rossi
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Vera Konieczny
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Daniel Bakowski
- Centre of Integrative Physiology, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Colin W Taylor
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Barry V L Potter
- Drug Discovery & Medicinal Chemistry, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
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8
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Mannino MP, Demchenko AV. Synthesis of β-Glucosides with 3-O-Picoloyl-Protected Glycosyl Donors in the Presence of Excess Triflic Acid: Defining the Scope. Chemistry 2020; 26:2938-2946. [PMID: 31886911 DOI: 10.1002/chem.201905278] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Indexed: 11/08/2022]
Abstract
Excellent β-stereoselectivity for the glycosylation with glucosyl donors equipped with the 3-O-picoloyl (Pico) group, without the use of participating group, was achieved in the presence of NIS/excess TfOH promoter system. A complete investigation of the scope of this reaction was performed, revealing all important attributes of successful glycosylation. While altering the halogen source was tolerated, substitution of the triflate anion resulted in complete loss of stereoselectivity. Protonation of the Pico group was determined to be crucial in this reaction. The stability or extent of the protonated pyridine ring was also found to be another important key factor in obtaining high stereoselectivity. The nucleophilicity of the acceptor was found to be proportional to the stereoselectivity obtained, suggesting an SN 2-like mechanism.
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Affiliation(s)
- Michael P Mannino
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri, 63121, USA
| | - Alexei V Demchenko
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri, 63121, USA
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9
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Mannino MP, Demchenko AV. Synthesis of β-Glucosides with 3-O-Picoloyl-Protected Glycosyl Donors in the Presence of Excess Triflic Acid: A Mechanistic Study. Chemistry 2020; 26:2927-2937. [PMID: 31886924 DOI: 10.1002/chem.201905277] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Indexed: 12/26/2022]
Abstract
Our previous study showed that picoloylated donors are capable of providing excellent facial stereoselectivity through the H-bond-mediated aglycone delivery (HAD) pathway. Presented herein is a detailed mechanistic study of stereoselective glycosylation with 3-O-picoloylated glucosyl donors. While reactions of glycosyl donors equipped with the 3-O-benzoyl group are typically non-stereoselective because these reactions proceed via the oxacarbenium intermediate, 3-O-picoloylated donors are capable of providing enhanced, but somewhat relaxed, β-stereoselectivity by the HAD pathway. In an attempt to refine this reaction, we noticed that glycosylations are highly β-stereoselective in the presence of NIS and stoichiometric TfOH. The HAD pathway is highly unlikely because the picoloyl nitrogen is protonated under these reaction conditions. The protonation and glycosylation were studied by low-temperature NMR, and the intermediacy of the glycosyl triflate has been observed. This article is dedicated to broadening the scope of this reaction in application to a variety of substrates and targets.
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Affiliation(s)
- Michael P Mannino
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri, 63121, USA
| | - Alexei V Demchenko
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri, 63121, USA
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10
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Dohle W, Su X, Mills SJ, Rossi AM, Taylor CW, Potter BVL. A synthetic cyclitol-nucleoside conjugate polyphosphate is a highly potent second messenger mimic. Chem Sci 2019; 10:5382-5390. [PMID: 31171961 PMCID: PMC6540904 DOI: 10.1039/c9sc00445a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
A densely functionalised phosphorylated chiro-inositol-nucleoside ether conjugate constructed from cyclic fragments is the most potent IP3 receptor ligand discovered.
Reactions that form sec–sec ethers are well known, but few lead to compounds with dense functionality around the O-linkage. Replacement of the α-glucopyranosyl unit of adenophostin A, a potent d-myo-inositol 1,4,5-trisphosphate (IP3R) agonist, with a d-chiro-inositol surrogate acting substantially as a pseudosugar, leads to “d-chiro-inositol adenophostin”. At its core, this cyclitol-nucleoside trisphosphate comprises an ether linkage between the axial 1-hydroxyl position of d-chiro-inositol and the 3′-hydroxyl group of an adenosine ribose sugar. A divergent synthesis of d-chiro-inositol adenophostin has been achieved. Key features of the synthetic strategy to produce a triol for phosphorylation include a new selective mono-tosylation of racemic 1,2:4,5-di-O-isopropylidene-myo-inositol using tosyl imidazole; subsequent conversion of the product into separable camphanate ester derivatives, one leading to a chiral myo-inositol triflate used as a synthetic building block and the other to l-1-O-methyl-myo-inositol [l-(+)-bornesitol] to assign the absolute configuration; the nucleophilic coupling of an alkoxide of a ribose pent-4-ene orthoester unit with a structurally rigid chiral myo-inositol triflate derivative, representing the first sec–sec ether formation between a cyclitol and ribose. Reaction of the coupled product with a silylated nucleobase completes the assembly of the core structure. Further protecting group manipulation, mixed O- and N-phosphorylation, and subsequent removal of all protecting groups in a single step achieves the final product, avoiding a separate N6 protection/deprotection strategy. d-chiro-Inositol adenophostin evoked Ca2+ release through IP3Rs at lower concentrations than adenophostin A, hitherto the most potent known agonist of IP3Rs.
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Affiliation(s)
- Wolfgang Dohle
- Medicinal Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Xiangdong Su
- Medicinal Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Stephen J Mills
- Medicinal Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Ana M Rossi
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
| | - Colin W Taylor
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
| | - Barry V L Potter
- Medicinal Chemistry & Drug Discovery, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
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11
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Rossi AM, Taylor CW. IP3 receptors – lessons from analyses ex cellula. J Cell Sci 2018; 132:132/4/jcs222463. [DOI: 10.1242/jcs.222463] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
ABSTRACT
Inositol 1,4,5-trisphosphate receptors (IP3Rs) are widely expressed intracellular channels that release Ca2+ from the endoplasmic reticulum (ER). We review how studies of IP3Rs removed from their intracellular environment (‘ex cellula’), alongside similar analyses of ryanodine receptors, have contributed to understanding IP3R behaviour. Analyses of permeabilized cells have demonstrated that the ER is the major intracellular Ca2+ store, and that IP3 stimulates Ca2+ release from this store. Radioligand binding confirmed that the 4,5-phosphates of IP3 are essential for activating IP3Rs, and facilitated IP3R purification and cloning, which paved the way for structural analyses. Reconstitution of IP3Rs into lipid bilayers and patch-clamp recording from the nuclear envelope have established that IP3Rs have a large conductance and select weakly between Ca2+ and other cations. Structural analyses are now revealing how IP3 binding to the N-terminus of the tetrameric IP3R opens the pore ∼7 nm away from the IP3-binding core (IBC). Communication between the IBC and pore passes through a nexus of interleaved domains contributed by structures associated with the pore and cytosolic domains, which together contribute to a Ca2+-binding site. These structural analyses provide evidence to support the suggestion that IP3 gates IP3Rs by first stimulating Ca2+ binding, which leads to pore opening and Ca2+ release.
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Affiliation(s)
- Ana M. Rossi
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
| | - Colin W. Taylor
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK
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12
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Riley AM, Unterlass JE, Konieczny V, Taylor CW, Helleday T, Potter BVL. A synthetic diphosphoinositol phosphate analogue of inositol trisphosphate. MEDCHEMCOMM 2018; 9:1105-1113. [PMID: 30079174 PMCID: PMC6071853 DOI: 10.1039/c8md00149a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 05/01/2018] [Indexed: 01/17/2023]
Abstract
Diphosphoinositol phosphates (PP-InsPs) are inositol phosphates (InsPs) that contain PP (diphosphate) groups. Converting a phosphate group in an InsP into a diphosphate has been reported to enhance affinity for some binding proteins. We synthesised 1-PP-Ins(4,5)P2, the first diphosphate analogue of the intracellular signalling molecule InsP3, and examined its effects on InsP3 receptors, which are intracellular Ca2+ channels. 1-PP-Ins(4,5)P2 was indistinguishable from InsP3 in its ability to bind to and activate type 1 InsP3 receptors, indicating that the diphosphate modification of InsP3 affected neither affinity nor efficacy. Nevertheless, 1-PP-Ins(4,5)P2 is the most potent 1-phosphate modified analogue of InsP3 yet identified. PP-InsPs are generally hydrolysed by diphosphoinositol phosphate phosphohydrolases (DIPPs), but 1-PP-Ins(4,5)P2 was not readily metabolised by human DIPPs. Differential scanning fluorimetry showed that 1-PP-Ins(4,5)P2 stabilises DIPP proteins, but to a lesser extent than naturally occurring substrates 1-PP-InsP5 and 5-PP-InsP5. The non-hydrolysable InsP7 analogues 1-PCP-InsP5 and 5-PCP-InsP5 showed comparable stabilising abilities to their natural counterparts and may therefore be promising substrate analogues for co-crystallisation with DIPPs.
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Affiliation(s)
- Andrew M. Riley
- Medicinal Chemistry and Drug Discovery
, Department of Pharmacology
, University of Oxford
,
Mansfield Road
, Oxford OX1 3QT
, UK
.
; Fax: +44 (0)1865 271853
; Tel: +44 (0)1865 271945
| | - Judith E. Unterlass
- Science for Life Laboratory
, Department of Oncology-Pathology
, Karolinska Institutet
,
SE-171 21 Solna
, Sweden
| | - Vera Konieczny
- Department of Pharmacology
, University of Cambridge
,
Tennis Court Road
, Cambridge CB2 1PD
, UK
| | - Colin W. Taylor
- Department of Pharmacology
, University of Cambridge
,
Tennis Court Road
, Cambridge CB2 1PD
, UK
| | - Thomas Helleday
- Science for Life Laboratory
, Department of Oncology-Pathology
, Karolinska Institutet
,
SE-171 21 Solna
, Sweden
| | - Barry V. L. Potter
- Medicinal Chemistry and Drug Discovery
, Department of Pharmacology
, University of Oxford
,
Mansfield Road
, Oxford OX1 3QT
, UK
.
; Fax: +44 (0)1865 271853
; Tel: +44 (0)1865 271945
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13
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Wu C, Li Y, Liu M, Liu J, Hua X, Zhang D, Xiong L, Yang N, Wang B, Li Z. Design, Synthesis, and Insecticidal Activities of Novel Pyranoside Derivatives Targeting at Potential Second Calcium Channel IP3Receptor. CHINESE J CHEM 2016. [DOI: 10.1002/cjoc.201600460] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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14
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Vibhute AM, Pushpanandan P, Varghese M, Koniecnzy V, Taylor CW, Sureshan KM. Synthesis of dimeric analogs of adenophostin A that potently evoke Ca 2+ release through IP 3 receptors. RSC Adv 2016; 6:86346-86351. [PMID: 28066549 PMCID: PMC5171214 DOI: 10.1039/c6ra19413c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 09/05/2016] [Indexed: 11/21/2022] Open
Abstract
Syntheses and Ca2+ release potentials of four dimeric analogs of adenophostin A (AdA) through activation of type 1 IP3R are reported. These analogs are full agonists of IP3R and are equipotent to AdA, the most potent agonist of IP3R.
Inositol 1,4,5-trisphosphate receptors (IP3Rs) are tetrameric intracellular channels through which many extracellular stimuli initiate the Ca2+ signals that regulate diverse cellular responses. There is considerable interest in developing novel ligands of IP3R. Adenophostin A (AdA) is a potent agonist of IP3R and since some dimeric analogs of IP3R ligands are more potent than the corresponding monomer; we considered whether dimeric AdA analogs might provide agonists with increased potency. We previously synthesized traizolophostin, in which a simple triazole replaced the adenine of AdA, and showed it to be equipotent to AdA. Here, we used click chemistry to synthesize four homodimeric analogs of triazolophostin, connected by oligoethylene glycol chains of different lengths. We evaluated the potency of these analogs to release Ca2+ through type 1 IP3R and established that the newly synthesized dimers are equipotent to AdA and triazolophostin.
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Affiliation(s)
- Amol M Vibhute
- School of Chemistry , Indian Institute of Science Education and Research Thiruvananthapuram , Kerala 695016 , India . ; http://kms514.wix.com/kmsgroup
| | - Poornenth Pushpanandan
- School of Chemistry , Indian Institute of Science Education and Research Thiruvananthapuram , Kerala 695016 , India . ; http://kms514.wix.com/kmsgroup
| | - Maria Varghese
- School of Chemistry , Indian Institute of Science Education and Research Thiruvananthapuram , Kerala 695016 , India . ; http://kms514.wix.com/kmsgroup
| | - Vera Koniecnzy
- Department of Pharmacology , University of Cambridge , Tennis Court Road , Cambridge , CB2 1PD , UK
| | - Colin W Taylor
- Department of Pharmacology , University of Cambridge , Tennis Court Road , Cambridge , CB2 1PD , UK
| | - Kana M Sureshan
- School of Chemistry , Indian Institute of Science Education and Research Thiruvananthapuram , Kerala 695016 , India . ; http://kms514.wix.com/kmsgroup
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15
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Vibhute AM, Konieczny V, Taylor CW, Sureshan KM. Triazolophostins: a library of novel and potent agonists of IP3 receptors. Org Biomol Chem 2016; 13:6698-710. [PMID: 25869535 PMCID: PMC4533600 DOI: 10.1039/c5ob00440c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
IP3R initiate most cellular Ca2+ signaling. AdA is the most potent agonist of IP3R. The structural complexity of AdA makes synthesis of its analogs cumbersome. We report an easy method for generating a library of potent triazole-based analogs of AdA, triazolophostins, which are the most potent AdA analogs devoid of a nucleobase.
IP3 receptors are channels that mediate the release of Ca2+ from the intracellular stores of cells stimulated by hormones or neurotransmitters. Adenophostin A (AdA) is the most potent agonist of IP3 receptors, with the β-anomeric adenine contributing to the increased potency. The potency of AdA and its stability towards the enzymes that degrade IP3 have aroused interest in AdA analogs for biological studies. The complex structure of AdA poses problems that have necessitated optimization of synthetic conditions for each analog. Such lengthy one-at-a-time syntheses limit access to AdA analogs. We have addressed this problem by synthesizing a library of triazole-based AdA analogs, triazolophostins, by employing click chemistry. An advanced intermediate having all the necessary phosphates and a β-azide at the anomeric position was reacted with various alkynes under Cu(i) catalysis to yield triazoles, which upon deprotection gave triazolophostins. All eleven triazolophostins synthesized are more potent than IP3 and some are equipotent with AdA in functional analyses of IP3 receptors. We show that a triazole ring can replace adenine without compromising the potency of AdA and provide facile routes to novel AdA analogs.
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Affiliation(s)
- Amol M Vibhute
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala-695016, India.
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16
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Konieczny V, Stefanakis JG, Sitsanidis ED, Ioannidou NAT, Papadopoulos NV, Fylaktakidou KC, Taylor CW, Koumbis AE. Synthesis of inositol phosphate-based competitive antagonists of inositol 1,4,5-trisphosphate receptors. Org Biomol Chem 2016; 14:2504-14. [PMID: 26818818 DOI: 10.1039/c5ob02623g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Inositol 1,4,5-trisphosphate receptors (IP3Rs) are intracellular Ca(2+) channels that are widely expressed in animal cells, where they mediate the release of Ca(2+) from intracellular stores evoked by extracellular stimuli. A diverse array of synthetic agonists of IP3Rs has defined structure-activity relationships, but existing antagonists have severe limitations. We combined analyses of Ca(2+) release with equilibrium competition binding to IP3R to show that (1,3,4,6)IP4 is a full agonist of IP3R1 with lower affinity than (1,4,5)IP3. Systematic manipulation of this meso-compound via a versatile synthetic scheme provided a family of dimeric analogs of 2-O-butyryl-(1,3,4,6)IP4 and (1,3,4,5,6)IP5 that compete with (1,4,5)IP3 for binding to IP3R without evoking Ca(2+) release. These novel analogs are the first inositol phosphate-based competitive antagonists of IP3Rs with affinities comparable to that of the only commonly used competitive antagonist, heparin, the utility of which is limited by off-target effects.
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Affiliation(s)
- Vera Konieczny
- Department of Pharmacology, Tennis Court Road, Cambridge, CB2 1PD, UK.
| | - John G Stefanakis
- Laboratory of Organic Chemistry, Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
| | - Efstratios D Sitsanidis
- Laboratory of Organic Chemistry, Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
| | - Natalia-Anastasia T Ioannidou
- Laboratory of Organic Chemistry, Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
| | - Nikolaos V Papadopoulos
- Laboratory of Organic Chemistry, Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
| | - Konstantina C Fylaktakidou
- Laboratory of Organic, Bioorganic and Natural Product Chemistry, Molecular Biology and Genetics Department, Democritus University of Thrace, 68100 Alexandroupolis, Greece
| | - Colin W Taylor
- Department of Pharmacology, Tennis Court Road, Cambridge, CB2 1PD, UK.
| | - Alexandros E Koumbis
- Laboratory of Organic Chemistry, Chemistry Department, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
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17
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Abstract
Synthetic compounds open up new avenues to interrogate and manipulate intracellular Ca2+ signalling pathways. They may ultimately lead to drug-like analogues to intervene in disease. Recent advances in chemical biology tools available to probe Ca2+ signalling are described, with a particular focus on those synthetic analogues from our group that have enhanced biological understanding or represent a step towards more drug-like molecules. Adenophostin (AdA) is the most potent known agonist at the inositol 1,4,5-trisphosphate receptor (IP3R) and synthetic analogues provide a binding model for receptor activation and channel opening. 2-O-Modified inositol 1,4,5-trisphosphate (IP3) derivatives that are partial agonists at the IP3R reveal key conformational changes of the receptor upon ligand binding. Biphenyl polyphosphates illustrate that simple non-inositol surrogates can be engineered to give prototype IP3R agonists or antagonists and act as templates for protein co-crystallization. Cyclic adenosine 5'-diphosphoribose (cADPR) can be selectively modified using total synthesis, generating chemically and biologically stable tools to investigate Ca2+ release via the ryanodine receptor (RyR) and to interfere with cADPR synthesis and degradation. The first neutral analogues with a synthetic pyrophosphate bioisostere surprisingly retain the ability to release Ca2+, suggesting a new route to membrane-permeant tools. Adenosine 5'-diphosphoribose (ADPR) activates the Ca2+-, Na+- and K+-permeable transient receptor potential melastatin 2 (TRPM2) cation channel. Synthetic ADPR analogues provide the first structure-activity relationship (SAR) for this emerging messenger and the first functional antagonists. An analogue based on the nicotinic acid motif of nicotinic acid adenine dinucleotide phosphate (NAADP) antagonizes NAADP-mediated Ca2+ release in vitro and is effective in vivo against induced heart arrhythmia and autoimmune disease, illustrating the therapeutic potential of targeted small molecules.
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18
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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: 110] [Impact Index Per Article: 13.8] [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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19
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Komarova BS, Tsvetkov YE, Nifantiev NE. Design of α-Selective Glycopyranosyl Donors Relying on Remote Anchimeric Assistance. CHEM REC 2016; 16:488-506. [PMID: 26785933 DOI: 10.1002/tcr.201500245] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Indexed: 11/08/2022]
Abstract
Oligosaccharides have a variety of versatile biological effects, but unlike peptides and oligonucleotides, investigation of the roles of oligosaccharides is not easy. Since biosynthesis of oligosaccharides does not comply with direct genetic control, their isolation from natural sources and biotechnological preparation are complicated, due to the heterogeneous composition of raw carbohydrates. Oligosaccharide synthesis is needed for the establishment or confirmation of the structure of natural glycocompounds. Also, synthetically prepared, defined oligosaccharides and their derivatives are becoming increasingly important tools for many biological and immunological research projects. The key step of oligosaccharide synthesis involves glycosylation, a reaction that builds glycosidic bonds. Usually, construction of 1,2-trans-bonds is easy, and therefore, this reaction can even be included into automated syntheses. At this time, installation of the 1,2-cis-bond remains simultaneously frustrating and compelling. In our and other laboratories, a strategy of α-selective (1,2-cis) glycosylation, relying on remote anchimeric assistance with acyl groups, is studied. The state of the art in this work is summarized in this review.
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Affiliation(s)
- Bozhena S Komarova
- Laboratory of Glycoconjugate Chemistry, N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, Leninsky Prospect 47, 119991, Moscow, Russia
| | - Yury E Tsvetkov
- Laboratory of Glycoconjugate Chemistry, N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, Leninsky Prospect 47, 119991, Moscow, Russia
| | - Nikolay E Nifantiev
- Laboratory of Glycoconjugate Chemistry, N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, Leninsky Prospect 47, 119991, Moscow, Russia
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20
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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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21
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Saleem H, Tovey SC, Riley AM, Potter BVL, Taylor CW. Stimulation of inositol 1,4,5-trisphosphate (IP3) receptor subtypes by adenophostin A and its analogues. PLoS One 2013; 8:e58027. [PMID: 23469136 PMCID: PMC3585173 DOI: 10.1371/journal.pone.0058027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 01/30/2013] [Indexed: 11/25/2022] Open
Abstract
Inositol 1,4,5-trisphosphate receptors (IP3R) are intracellular Ca(2+) channels. Most animal cells express mixtures of the three IP3R subtypes encoded by vertebrate genomes. Adenophostin A (AdA) is the most potent naturally occurring agonist of IP3R and it shares with IP3 the essential features of all IP3R agonists, namely structures equivalent to the 4,5-bisphosphate and 6-hydroxyl of IP3. The two essential phosphate groups contribute to closure of the clam-like IP3-binding core (IBC), and thereby IP3R activation, by binding to each of its sides (the α- and β-domains). Regulation of the three subtypes of IP3R by AdA and its analogues has not been examined in cells expressing defined homogenous populations of IP3R. We measured Ca(2+) release evoked by synthetic adenophostin A (AdA) and its analogues in permeabilized DT40 cells devoid of native IP3R and stably expressing single subtypes of mammalian IP3R. The determinants of high-affinity binding of AdA and its analogues were indistinguishable for each IP3R subtype. The results are consistent with a cation-π interaction between the adenine of AdA and a conserved arginine within the IBC α-domain contributing to closure of the IBC. The two complementary contacts between AdA and the α-domain (cation-π interaction and 3″-phosphate) allow activation of IP3R by an analogue of AdA (3″-dephospho-AdA) that lacks a phosphate group equivalent to the essential 5-phosphate of IP3. These data provide the first structure-activity analyses of key AdA analogues using homogenous populations of all mammalian IP3R subtypes. They demonstrate that differences in the Ca(2+) signals evoked by AdA analogues are unlikely to be due to selective regulation of IP3R subtypes.
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Affiliation(s)
- Huma Saleem
- Department of Pharmacology, Cambridge, United Kingdom
| | | | - Andrew M. Riley
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom
| | - Barry V. L. Potter
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom
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22
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Saleem H, Tovey SC, Rahman T, Riley AM, Potter BVL, Taylor CW. Stimulation of inositol 1,4,5-trisphosphate (IP3) receptor subtypes by analogues of IP3. PLoS One 2013; 8:e54877. [PMID: 23372785 PMCID: PMC3556037 DOI: 10.1371/journal.pone.0054877] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 12/17/2012] [Indexed: 11/19/2022] Open
Abstract
Most animal cells express mixtures of the three subtypes of inositol 1,4,5-trisphosphate receptor (IP(3)R) encoded by vertebrate genomes. Activation of each subtype by different agonists has not hitherto been examined in cells expressing defined homogenous populations of IP(3)R. Here we measure Ca(2+) release evoked by synthetic analogues of IP(3) using a Ca(2+) indicator within the lumen of the endoplasmic reticulum of permeabilized DT40 cells stably expressing single subtypes of mammalian IP(3)R. Phosphorylation of (1,4,5)IP(3) to (1,3,4,5)IP(4) reduced potency by ~100-fold. Relative to (1,4,5)IP(3), the potencies of IP(3) analogues modified at the 1-position (malachite green (1,4,5)IP(3)), 2-position (2-deoxy(1,4,5)IP(3)) or 3-position (3-deoxy(1,4,5)IP(3), (1,3,4,5)IP(4)) were similar for each IP(3)R subtype. The potency of an analogue, (1,4,6)IP(3), in which the orientations of the 2- and 3-hydroxyl groups were inverted, was also reduced similarly for all three IP(3)R subtypes. Most analogues of IP(3) interact similarly with the three IP(3)R subtypes, but the decrease in potency accompanying removal of the 1-phosphate from (1,4,5)IP(3) was least for IP(3)R3. Addition of a large chromophore (malachite green) to the 1-phosphate of (1,4,5)IP(3) only modestly reduced potency suggesting that similar analogues could be used to measure (1,4,5)IP(3) binding optically. These data provide the first structure-activity analyses of key IP(3) analogues using homogenous populations of each mammalian IP(3)R subtype. They demonstrate broadly similar structure-activity relationships for all mammalian IP(3)R subtypes and establish the potential utility of (1,4,5)IP(3) analogues with chromophores attached to the 1-position.
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MESH Headings
- Amino Acid Sequence
- Animals
- Calcium/metabolism
- Cell Line
- Gene Expression
- Inositol 1,4,5-Trisphosphate/chemistry
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors/chemistry
- Inositol 1,4,5-Trisphosphate Receptors/genetics
- Inositol 1,4,5-Trisphosphate Receptors/metabolism
- Kinetics
- Ligands
- Mice
- Models, Molecular
- Molecular Docking Simulation
- Molecular Sequence Data
- Molecular Structure
- Protein Binding
- Rats
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Structure-Activity Relationship
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Affiliation(s)
- Huma Saleem
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | - Stephen C. Tovey
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | - Taufiq Rahman
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | - Andrew M. Riley
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom
| | - Barry V. L. Potter
- Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, United Kingdom
| | - Colin W. Taylor
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
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