1
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Rrapi M, Batsika CS, Nikitas NF, Tappin NDC, Triandafillidi I, Renaud P, Kokotos CG. Photochemical Synthesis of Lactones, Cyclopropanes and ATRA Products: Revealing the Role of Sodium Ascorbate. Chemistry 2024; 30:e202400253. [PMID: 38324672 DOI: 10.1002/chem.202400253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Revised: 02/06/2024] [Accepted: 02/06/2024] [Indexed: 02/09/2024]
Abstract
Light-mediated processes have received significant attention, since they have re-surfaced unconventional reactivity platforms, complementary to conventional polar chemistry. γ-Lactones and cyclopropanes are prevalent moieties, found in numerous natural products and pharmaceuticals. Among various methods for their synthesis, light-mediated protocols are coming to the spotlight, although these are contingent upon the use of photoorgano- or metal-based catalysts. Herein, we introduce a novel photochemical activation of iodo-reagents via the use of cheap sodium ascorbate or ascorbic acid to enable their homolytic scission and addition onto double bonds. The developed protocol was applied successfully to the formal [3+2] cycloaddition for the synthesis of γ-lactones, traditional atom transfer radical addition (ATRA) reactions and the one-pot two-step conversion of alkenes to cyclopropanes. In all cases, the desired products were obtained in good to high yields, while the reaction mechanism was thoroughly investigated. Depending on the nature of the iodo-reagent, a halogen or a hydrogen-bonded complex is formed, which initiates the process.
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Affiliation(s)
- Marie Rrapi
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens, 15771, Greece
| | - Charikleia S Batsika
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens, 15771, Greece
| | - Nikolaos F Nikitas
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens, 15771, Greece
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Nicholas D C Tappin
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Ierasia Triandafillidi
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens, 15771, Greece
| | - Philippe Renaud
- Department of Chemistry, Biochemistry, and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Christoforos G Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens, 15771, Greece
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2
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Xie X, Dong S, Hong K, Huang J, Xu X. Catalytic Asymmetric Difluoroalkylation Using In Situ Generated Difluoroenol Species as the Privileged Synthon. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2307520. [PMID: 38318687 PMCID: PMC11005710 DOI: 10.1002/advs.202307520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/29/2023] [Indexed: 02/07/2024]
Abstract
A robust and practical difluoroalkylation synthon, α,α-difluoroenol species, which generated in situ from trifluoromethyl diazo compounds and water in the presence of dirhodium complex, is disclosed. As compared to the presynthesized difluoroenoxysilane and in situ formed difluoroenolate under basic conditions, this difluoroenol intermediate displayed versatile reactivity, resulting in dramatically improved enantioselectivity under mild conditions. As demonstrated in catalytic asymmetric aldol reaction and Mannich reactions with ketones or imines in the presence of chiral organocatalysts, quinine-derived urea, and chiral phosphoric acid (CPA), respectively, this relay catalysis strategy provides an effective platform for applying asymmetric fluorination chemistry. Moreover, this method features a novel 1,2-difunctionalization process via installation of a carbonyl motif and an alkyl group on two vicinal carbons, which is a complementary protocol to the metal carbene gem-difunctionalization reaction.
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Affiliation(s)
- Xiongda Xie
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, P. R. China
| | - Shanliang Dong
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, P. R. China
| | - Kemiao Hong
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, P. R. China
| | - Jingjing Huang
- School of Chemistry, Sun Yat-Sen University, Guangzhou, Guangdong, 510275, P. R. China
| | - Xinfang Xu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, P. R. China
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3
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Hou YJ, Zhao L, Chai GL, Zhong K, Chang J. Highly Enantioselective Chiral Diol-Catalyzed Conjugate Addition of Boronic Acids to α,β-Unsaturated Trifluoromethyl Ketones. J Org Chem 2023. [PMID: 38006355 DOI: 10.1021/acs.joc.3c02281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2023]
Abstract
The (R)-3,3'-(3,5-(CF3)2-C6H3)2-BINOL-catalyzed enantioselective conjugate addition of organic boronic acids to α,β-unsaturated 1,1,1-trifluoromethyl ketones affords corresponding addition products bearing a stereogenic center at the β-position in moderate to high yields and excellent enantioselectivities (up to 99% ee), without any 1,2-addition product formation. Moreover, this catalytic protocol features mild reaction conditions, a broad substrate scope, suitability for alkenylboronic acids and (hetero)arylboronic acids, and easy scale-up.
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Affiliation(s)
- Ya-Jing Hou
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Lu Zhao
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Guo-Li Chai
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Kangbao Zhong
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
| | - Junbiao Chang
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
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4
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Columbus I, Ghindes-Azaria L, Herzog IM, Blum E, Parvari G, Eichen Y, Cohen Y, Gershonov E, Drug E, Saphier S, Elias S, Smolkin B, Zafrani Y. Species-specific lipophilicities of fluorinated diketones in complex equilibria systems and their potential as multifaceted reversible covalent warheads. Commun Chem 2023; 6:197. [PMID: 37715018 PMCID: PMC10504258 DOI: 10.1038/s42004-023-01004-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 09/05/2023] [Indexed: 09/17/2023] Open
Abstract
Combined molecular, physicochemical and chemical properties of electrophilic warheads can be applied to create covalent drugs with diverse facets. Here we study these properties in fluorinated diketones (FDKs) and their multicomponent equilibrium systems in the presence of protic nucleophiles, revealing the potential of the CF2(CO)2 group to act as a multifaceted warhead for reversible covalent drugs. The equilibria compositions of various FDKs in water/octanol contain up to nine species. A simultaneous direct species-specific 19F-NMR-based log P determination of these complex equilibria systems was achieved and revealed in some cases lipophilic to hydrophilic shifts, indicating possible adaptation to different environments. This was also demonstrated in 19F-MAS-NMR-based water-membrane partitioning measurements. An interpretation of the results is suggested by the aid of a DFT study and 19F-DOSY-NMR spectroscopy. In dilute solutions, a model FDK reacted with protected cysteine to form two hemi-thioketal regioisomers, indicating possible flexible regio-reactivity of CF2(CO)2 warheads toward cysteine residues.
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Affiliation(s)
- Ishay Columbus
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Lee Ghindes-Azaria
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Ido Michael Herzog
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Eliav Blum
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Galit Parvari
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa, Israel
| | - Yoav Eichen
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa, Israel
| | - Yoram Cohen
- School of Chemistry, Tel Aviv University, Tel Aviv, Israel
| | - Eytan Gershonov
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Eyal Drug
- Department of Analytic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Sigal Saphier
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel.
| | - Shlomi Elias
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Boris Smolkin
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel
| | - Yossi Zafrani
- Department of Organic Chemistry, Israel Institute for Biological Research, Ness Ziona, Israel.
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5
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Putta P, Chaudhuri P, Guardia-Wolff R, Rosenbaum MA, Graham LM. iPLA2 inhibition blocks LysoPC-induced TRPC6 externalization and promotes Re-endothelialization of carotid injuries in hypercholesterolemic mice. Cell Calcium 2023; 112:102734. [PMID: 37030190 PMCID: PMC10234282 DOI: 10.1016/j.ceca.2023.102734] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 03/13/2023] [Accepted: 03/30/2023] [Indexed: 04/10/2023]
Abstract
Lipid oxidation products, including lysophosphatidylcholine (lysoPC), accumulate at the site of arterial injury after vascular interventions and hinder re-endothelization. LysoPC activates calcium-permeable channels, specifically canonical transient receptor potential 6 (TRPC6) channels that induce a sustained increase in intracellular calcium ion concentration [Ca2+]i and contribute to dysregulation of the endothelial cell (EC) cytoskeleton. Activation of TRPC6 leads to inhibition of EC migration in vitro and delayed re-endothelization of arterial injuries in vivo. Previously, we demonstrated the role of phospholipase A2 (PLA2), specifically calcium-independent PLA2 (iPLA2), in lysoPC-induced TRPC6 externalization and inhibition of EC migration in vitro. The ability of FKGK11, an iPLA2-specific pharmacological inhibitor, to block TRPC6 externalization and preserve EC migration was assessed in vitro and in a mouse model of carotid injury. Our data suggest that FKGK11 prevents lysoPC-induced PLA2 activity, blocks TRPC6 externalization, attenuates calcium influx, and partially preserves EC migration in vitro. Furthermore, FKGK11 promotes re-endothelization of an electrocautery carotid injury in hypercholesterolemic mice. FKGK11 has similar arterial healing effects in male and female mice on a high-fat diet. This study suggests that iPLA2 is a potential therapeutic target to attenuate calcium influx through TRPC6 channels and promote EC healing in cardiovascular patients undergoing angioplasty.
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Affiliation(s)
- Priya Putta
- Department of Biomedical Engineering, Cleveland Clinic, Cleveland, OH, 44195, United States.
| | - Pinaki Chaudhuri
- Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, 44106, United States
| | - Rocio Guardia-Wolff
- Department of Biomedical Engineering, Cleveland Clinic, Cleveland, OH, 44195, United States
| | - Michael A Rosenbaum
- Surgical Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, 44106, United States
| | - Linda M Graham
- Department of Biomedical Engineering, Cleveland Clinic, Cleveland, OH, 44195, United States; Department of Vascular Surgery, Cleveland Clinic, Cleveland, OH, 44195, United States
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6
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Zhang X, Zhang X, Song Q, Sivaguru P, Wang Z, Zanoni G, Bi X. A Carbene Strategy for Progressive (Deutero)Hydrodefluorination of Fluoroalkyl Ketones. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202116190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Xiaolong Zhang
- Department of Chemistry Northeast Normal University Changchun 130024 China
| | - Xinyu Zhang
- Department of Chemistry Northeast Normal University Changchun 130024 China
| | - Qingmin Song
- Department of Chemistry Northeast Normal University Changchun 130024 China
| | | | - Zikun Wang
- Department of Chemistry Northeast Normal University Changchun 130024 China
| | - Giuseppe Zanoni
- Department of Chemistry University of Pavia Viale Taramelli 12 27100 Pavia Italy
| | - Xihe Bi
- Department of Chemistry Northeast Normal University Changchun 130024 China
- State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China
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7
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Mild and efficient one-pot synthesis of (E)-styrylperfluoroalkyl ketone from styrene. RESULTS IN CHEMISTRY 2022. [DOI: 10.1016/j.rechem.2021.100260] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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8
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Zhang X, Zhang X, Song Q, Sivaguru P, Wang Z, Zanoni G, Bi X. A Carbene Strategy for Progressive (Deutero)Hydrodefluorination of Fluoroalkyl Ketones. Angew Chem Int Ed Engl 2021; 61:e202116190. [PMID: 34889004 DOI: 10.1002/anie.202116190] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Indexed: 12/29/2022]
Abstract
Hydrodefluorination is one of the most promising chemical strategies to degrade perfluorochemicals into partially fluorinated compounds. However, controlled progressive hydrodefluorination remains a significant challenge, owing to the decrease in the strength of C-F bonds along with the defluorination. Here we describe a carbene strategy for the sequential (deutero)hydrodefluorination of perfluoroalkyl ketones under rhodium catalysis, allowing for the controllable preparation of difluoroalkyl- and monofluoroalkyl ketones from aryl- and even alkyl-substituted perfluoro-alkyl ketones in high yield with excellent functional group tolerance. The reaction mechanism and the origin of the intriguing chemoselectivity of the reaction were rationalized by density functional theory (DFT) calculations.
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Affiliation(s)
- Xiaolong Zhang
- Department of Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Xinyu Zhang
- Department of Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Qingmin Song
- Department of Chemistry, Northeast Normal University, Changchun, 130024, China
| | | | - Zikun Wang
- Department of Chemistry, Northeast Normal University, Changchun, 130024, China
| | - Giuseppe Zanoni
- Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy
| | - Xihe Bi
- Department of Chemistry, Northeast Normal University, Changchun, 130024, China.,State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, China
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9
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Lantaño B, Yerien DE, Barata-Vallejo S, Postigo A. Visible light-catalyzed fluoroalkylation reactions of free aniline derivatives. Photochem Photobiol Sci 2021; 20:971-983. [PMID: 34283407 DOI: 10.1007/s43630-021-00078-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 07/15/2021] [Indexed: 11/24/2022]
Abstract
The electron-rich nature of aminoaromatic compounds and the electrophilic character of fluoroalkyl RF radicals allow for a special match in substitution reactions. We herein present visible light photocatalyzed fluoroalkylation reactions of aniline derivatives, with a study of the reaction mechanisms. The examples evaluated make use of different photocatalysts, such as polypyridyl complexes of Ir or Ru transition metals, organic dyes such as Rose Bengal, phthalocyanine-metal organocatalysts, or visible-light activated complexes. Different visible light sources that span from the blue region of the electromagnetic spectrum to low power red light irradiation sources deliver the excited photocatalysts that ensue into the production of fluoroalkyl RF radicals. In turn, many sources of RF radicals can be employed, such as fluoroalkyl halides, Togni's reagents, Umemoto's reagent, etc. All these protocol variants demonstrate the expansion of the methodology and the versatility of photocatalytic techniques applied to a special family of organic compounds such as aminoaromatic substrates, which has been studied by different groups. Contributions from our own laboratory will be given.
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Affiliation(s)
- Beatriz Lantaño
- Departamento de Ciencias Químicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, CP 1113, Buenos Aires, Argentina
| | - Damian E Yerien
- Departamento de Ciencias Químicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, CP 1113, Buenos Aires, Argentina
| | - Sebastián Barata-Vallejo
- Departamento de Ciencias Químicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, CP 1113, Buenos Aires, Argentina.,ISOF, Consiglio Nazionale Delle Ricerche, Via P. Gobetti 101, 40129, Bologna, Italy
| | - Al Postigo
- Departamento de Ciencias Químicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 954, CP 1113, Buenos Aires, Argentina.
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10
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Batsika CS, Gerogiannopoulou ADD, Mantzourani C, Vasilakaki S, Kokotos G. The design and discovery of phospholipase A 2 inhibitors for the treatment of inflammatory diseases. Expert Opin Drug Discov 2021; 16:1287-1305. [PMID: 34143707 DOI: 10.1080/17460441.2021.1942835] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
AREAS COVERED This review article summarizes the most important synthetic PLA2 inhibitors developed to target each one of the four major types of human PLA2 (cytosolic cPLA2, calcium-independent iPLA2, secreted sPLA2, and lipoprotein-associated Lp-PLA2), discussing their in vitro and in vivo activities as well as their recent applications and therapeutic properties. Recent findings on the role of PLA2 in the pathobiology of COVID-19 are also discussed. EXPERT OPINION Although a number of PLA2 inhibitors have entered clinical trials, none has reached the market yet. Lipoprotein-associated PLA2 is now considered a biomarker of vascular inflammation rather than a therapeutic target for inhibitors like darapladib. Inhibitors of cytosolic PLA2 may find topical applications for diseases like atopic dermatitis and psoriasis. Inhibitors of secreted PLA2, varespladib and varespladib methyl, are under investigation for repositioning in snakebite envenoming. A deeper understanding of PLA2 enzymes is needed for the development of novel selective inhibitors. Lipidomic technologies combined with medicinal chemistry approaches may be useful tools toward this goal.
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Affiliation(s)
| | | | - Christiana Mantzourani
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Greece
| | - Sofia Vasilakaki
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Greece
| | - George Kokotos
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Greece
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11
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Shen T, Lambert TH. Electrophotocatalytic diamination of vicinal C-H bonds. Science 2021; 371:620-626. [PMID: 33542135 DOI: 10.1126/science.abf2798] [Citation(s) in RCA: 99] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 01/06/2021] [Indexed: 01/07/2023]
Abstract
The conversion of unactivated carbon-hydrogen (C-H) bonds to carbon-nitrogen (C-N) bonds is a highly valued transformation. Existing strategies typically accomplish such reactions at only a single C-H site because the first derivatization diminishes the reactivity of surrounding C-H bonds. Here, we show that alkylated arenes can undergo vicinal C-H diamination reactions to form 1,2-diamine derivatives through an electrophotocatalytic strategy, using acetonitrile as both solvent and nitrogen source. The reaction is catalyzed by a trisaminocyclopropenium (TAC) ion, which undergoes anodic oxidation to furnish a stable radical dication while the cathodic reaction reduces protons to molecular hydrogen. Irradiation of the TAC radical dication (wavelength of maximum absorption of 450 to 550 nanometers) with a white-light compact fluorescent light generates a strongly oxidizing photoexcited intermediate. Depending on the electrolyte used, either 3,4-dihydroimidazole or aziridine products are obtained.
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Affiliation(s)
- Tao Shen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14850, USA
| | - Tristan H Lambert
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14850, USA.
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12
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Type 1 interferon-dependent repression of NLRC4 and iPLA2 licenses down-regulation of Salmonella flagellin inside macrophages. Proc Natl Acad Sci U S A 2020; 117:29811-29822. [PMID: 33177235 DOI: 10.1073/pnas.2002747117] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Inflammasomes have been implicated in the detection and clearance of a variety of bacterial pathogens, but little is known about whether this innate sensing mechanism has any regulatory effect on the expression of stimulatory ligands by the pathogen. During infection with Salmonella and many other pathogens, flagellin is a major activator of NLRC4 inflammasome-mediated macrophage pyroptosis and pathogen eradication. Salmonella switches to a flagellin-low phenotype as infection progresses to avoid this mechanism of clearance by the host. However, the host cues that Salmonella perceives to undergo this switch remain unclear. Here, we report an unexpected role of the NLRC4 inflammasome in promoting expression of its microbial ligand, flagellin, and identify a role for type 1 IFN signaling in switching of Salmonella to a flagellin-low phenotype. Early in infection, activation of NLRC4 by flagellin initiates pyroptosis and concomitant release of lysophospholipids which in turn enhance expression of flagellin by Salmonella thereby amplifying its ability to elicit cell death. TRIF-dependent production of type 1 IFN, however, later represses NLRC4 and the lysophospholipid biosynthetic enzyme iPLA2, causing a decline in intracellular lysophospholipids that results in down-regulation of flagellin expression by Salmonella These findings reveal a previously unrecognized immune-modulating regulatory cross-talk between endosomal TLR signaling and cytosolic NLR activation with significant implications for the establishment of infection with Salmonella.
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13
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Nelson AJ, Stephenson DJ, Bone RN, Cardona CL, Park MA, Tusing YG, Lei X, Kokotos G, Graves CL, Mathews CE, Kramer J, Hessner MJ, Chalfant CE, Ramanadham S. Lipid mediators and biomarkers associated with type 1 diabetes development. JCI Insight 2020; 5:138034. [PMID: 32814707 PMCID: PMC7455134 DOI: 10.1172/jci.insight.138034] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 07/09/2020] [Indexed: 01/13/2023] Open
Abstract
Type 1 diabetes (T1D) is a consequence of autoimmune β cell destruction, but the role of lipids in this process is unknown. We previously reported that activation of Ca2+-independent phospholipase A2β (iPLA2β) modulates polarization of macrophages (MΦ). Hydrolysis of the sn-2 substituent of glycerophospholipids by iPLA2β can lead to the generation of oxidized lipids (eicosanoids), pro- and antiinflammatory, which can initiate and amplify immune responses triggering β cell death. As MΦ are early triggers of immune responses in islets, we examined the impact of iPLA2β-derived lipids (iDLs) in spontaneous-T1D prone nonobese diabetic mice (NOD), in the context of MΦ production and plasma abundances of eicosanoids and sphingolipids. We find that (a) MΦNOD exhibit a proinflammatory lipid landscape during the prediabetic phase; (b) early inhibition or genetic reduction of iPLA2β reduces production of select proinflammatory lipids, promotes antiinflammatory MΦ phenotype, and reduces T1D incidence; (c) such lipid changes are reflected in NOD plasma during the prediabetic phase and at T1D onset; and (d) importantly, similar lipid signatures are evidenced in plasma of human subjects at high risk for developing T1D. These findings suggest that iDLs contribute to T1D onset and identify select lipids that could be targeted for therapeutics and, in conjunction with autoantibodies, serve as early biomarkers of pre-T1D.
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Affiliation(s)
- Alexander J Nelson
- Department of Cell, Developmental, and Integrative Biology, and.,Comprehensive Diabetes Center, University of Alabama at Birmingham (UAB), Birmingham, Alabama, USA
| | - Daniel J Stephenson
- Department of Cell Biology, Microbiology and Molecular Biology (CMMB), University of South Florida, Tampa, Florida, USA
| | - Robert N Bone
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Christopher L Cardona
- Department of Cell Biology, Microbiology and Molecular Biology (CMMB), University of South Florida, Tampa, Florida, USA
| | - Margaret A Park
- Department of Cell Biology, Microbiology and Molecular Biology (CMMB), University of South Florida, Tampa, Florida, USA
| | - Ying G Tusing
- Department of Cell, Developmental, and Integrative Biology, and.,Comprehensive Diabetes Center, University of Alabama at Birmingham (UAB), Birmingham, Alabama, USA
| | - Xiaoyong Lei
- Department of Cell, Developmental, and Integrative Biology, and.,Comprehensive Diabetes Center, University of Alabama at Birmingham (UAB), Birmingham, Alabama, USA
| | - George Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens, Greece
| | - Christina L Graves
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida Health Science Center, Gainesville, Florida, USA
| | - Joanna Kramer
- Max McGee Research Center for Juvenile Diabetes, Department of Pediatrics at Medical College of Wisconsin and Children's Research Institute of Children's Hospital of Wisconsin, Milwaukee, Wisconsin, USA
| | - Martin J Hessner
- Max McGee Research Center for Juvenile Diabetes, Department of Pediatrics at Medical College of Wisconsin and Children's Research Institute of Children's Hospital of Wisconsin, Milwaukee, Wisconsin, USA
| | - Charles E Chalfant
- Department of Cell Biology, Microbiology and Molecular Biology (CMMB), University of South Florida, Tampa, Florida, USA.,Research Service, James A. Haley Veterans Hospital, Tampa, Florida, USA
| | - Sasanka Ramanadham
- Department of Cell, Developmental, and Integrative Biology, and.,Comprehensive Diabetes Center, University of Alabama at Birmingham (UAB), Birmingham, Alabama, USA
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14
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Li Y, Zhao YT, Zhou T, Chen MQ, Li YP, Huang MY, Xu ZC, Zhu SF, Zhou QL. Highly Enantioselective O-H Bond Insertion Reaction of α-Alkyl- and α-Alkenyl-α-diazoacetates with Water. J Am Chem Soc 2020; 142:10557-10566. [PMID: 32406233 DOI: 10.1021/jacs.0c04532] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Catalytic asymmetric reactions in which water is a substrate are rare. Enantioselective transition-metal-catalyzed insertion of carbenes into the O-H bond of water can be used to incorporate water into the stereogenic center, but the reported chiral catalysts give good results only when α-aryl-α-diazoesters are used as the carbene precursors. Herein we report the first highly enantioselective O-H bond insertion reactions between water and α-alkyl- and α-alkenyl-α-diazoesters as carbene precursors, with catalysis by a combination of achiral dirhodium complexes and chiral phosphoric acids or chiral phosphoramides. Participation of the phosphoric acids or phosphoramides in the carbene transfer reaction markedly suppressed competing side reactions, such as β-H migration, carbene dimerization, and olefin isomerization, and thus ensured good yields of the desired products. Fine-tuning of the ester moiety facilitated enantiocontrol of the proton transfer reactions of the enol intermediates and resulted in excellent enantioselectivity. This protocol represents an efficient new method for preparation of multifunctionalized chiral α-alkyl and α-alkenyl hydroxyl esters, which readily undergo various transformations and can thus be used for the synthesis of bioactive compounds. Mechanistic studies revealed that the phosphoric acids and phosphoramides promoted highly enantioselective [1,2]- and [1,3]-proton transfer reactions of the enol intermediates. Maximization of molecular orbital overlap in the transition states of the proton transfer reactions was the original driving force to involve the proton shuttle catalysts in this process.
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Affiliation(s)
- You Li
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yu-Tao Zhao
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Ting Zhou
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Meng-Qing Chen
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yi-Pan Li
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Ming-Yao Huang
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Zhen-Chuang Xu
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Shou-Fei Zhu
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Qi-Lin Zhou
- The State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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15
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Koutoulogenis GS, Kokotou MG, Hayashi D, Mouchlis VD, Dennis EA, Kokotos G. 2-Oxoester Phospholipase A 2 Inhibitors with Enhanced Metabolic Stability. Biomolecules 2020; 10:biom10030491. [PMID: 32213911 PMCID: PMC7175278 DOI: 10.3390/biom10030491] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 12/21/2022] Open
Abstract
2-Oxoesters constitute an important class of potent and selective inhibitors of human cytosolic phospholipase A2 (GIVA cPLA2) combining an aromatic scaffold or a long aliphatic chain with a short aliphatic chain containing a free carboxylic acid. Although highly potent 2-oxoester inhibitors of GIVA cPLA2 have been developed, their rapid degradation in human plasma limits their pharmaceutical utility. In an effort to address this problem, we designed and synthesized two new 2-oxoesters introducing a methyl group either on the α-carbon to the oxoester functionality or on the carbon carrying the ester oxygen. We studied the in vitro plasma stability of both derivatives and their in vitro inhibitory activity on GIVA cPLA2. Both derivatives exhibited higher plasma stability in comparison with the unsubstituted compound and both derivatives inhibited GIVA cPLA2, however to different degrees. The 2-oxoester containing a methyl group on the α-carbon atom to the oxoester functionality exhibits enhancement of the metabolic stability and retains considerable inhibitory potency.
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Affiliation(s)
- Giorgos S. Koutoulogenis
- Department of Chemistry, National and Kapodistrian University of Athens, Athens 15771, Greece; (G.S.K.); (M.G.K.)
| | - Maroula G. Kokotou
- Department of Chemistry, National and Kapodistrian University of Athens, Athens 15771, Greece; (G.S.K.); (M.G.K.)
| | - Daiki Hayashi
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0601, USA; (D.H.); (V.D.M.)
| | - Varnavas D. Mouchlis
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0601, USA; (D.H.); (V.D.M.)
| | - Edward A. Dennis
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0601, USA; (D.H.); (V.D.M.)
- Correspondence: (E.A.D.); (G.K.); Tel.: +1-858-534-3055 (E.A.D.); +30-210-7274462 (G.K.)
| | - George Kokotos
- Department of Chemistry, National and Kapodistrian University of Athens, Athens 15771, Greece; (G.S.K.); (M.G.K.)
- Correspondence: (E.A.D.); (G.K.); Tel.: +1-858-534-3055 (E.A.D.); +30-210-7274462 (G.K.)
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16
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Pertusati F, Ferla S, Bassetto M, Brancale A, Khandil S, Westwell AD, McGuigan C. A new series of bicalutamide, enzalutamide and enobosarm derivatives carrying pentafluorosulfanyl (SF5) and pentafluoroethyl (C2F5) substituents: Improved antiproliferative agents against prostate cancer. Eur J Med Chem 2019; 180:1-14. [DOI: 10.1016/j.ejmech.2019.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/30/2019] [Accepted: 07/01/2019] [Indexed: 01/31/2023]
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17
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Nikolaou A, Kokotou MG, Vasilakaki S, Kokotos G. Small-molecule inhibitors as potential therapeutics and as tools to understand the role of phospholipases A 2. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:941-956. [PMID: 30905350 PMCID: PMC7106526 DOI: 10.1016/j.bbalip.2018.08.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/10/2018] [Accepted: 08/16/2018] [Indexed: 11/20/2022]
Abstract
Phospholipase A2 (PLA2) enzymes are involved in various inflammatory pathological conditions including arthritis, cardiovascular and autoimmune diseases. The regulation of their catalytic activity is of high importance and a great effort has been devoted in developing synthetic inhibitors. We summarize the most important small-molecule synthetic PLA2 inhibitors developed to target each one of the four major types of human PLA2 (cytosolic cPLA2, calcium-independent iPLA2, secreted sPLA2, and lipoprotein-associated LpPLA2). We discuss recent applications of inhibitors to understand the role of each PLA2 type and their therapeutic potential. Potent and selective PLA2 inhibitors have been developed. Although some of them have been evaluated in clinical trials, none reached the market yet. Apart from their importance as potential medicinal agents, PLA2 inhibitors are excellent tools to unveil the role that each PLA2 type plays in cells and in vivo. Modern medicinal chemistry approaches are expected to generate improved PLA2 inhibitors as new agents to treat inflammatory diseases.
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Affiliation(s)
- Aikaterini Nikolaou
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - Maroula G Kokotou
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - Sofia Vasilakaki
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - George Kokotos
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece.
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18
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Dedaki C, Kokotou MG, Mouchlis VD, Limnios D, Lei X, Mu CT, Ramanadham S, Magrioti V, Dennis EA, Kokotos G. β-Lactones: A Novel Class of Ca 2+-Independent Phospholipase A 2 (Group VIA iPLA 2) Inhibitors with the Ability To Inhibit β-Cell Apoptosis. J Med Chem 2019; 62:2916-2927. [PMID: 30798607 DOI: 10.1021/acs.jmedchem.8b01216] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Ca2+-independent phospholipase A2 (GVIA iPLA2) has gained increasing interest recently as it has been recognized as a participant in biological processes underlying diabetes development and autoimmune-based neurological disorders. The development of potent GVIA iPLA2 inhibitors is of great importance because only a few have been reported so far. We present a novel class of GVIA iPLA2 inhibitors based on the β-lactone ring. This functionality in combination with a four-carbon chain carrying a phenyl group at position-3 and a linear propyl group at position-4 of the lactone ring confers excellent potency. trans-3-(4-Phenylbutyl)-4-propyloxetan-2-one (GK563) was identified as being the most potent GVIA iPLA2 inhibitor ever reported ( XI(50) 0.0000021, IC50 1 nM) and also one that is 22 000 times more active against GVIA iPLA2 than GIVA cPLA2. It was found to reduce β-cell apoptosis induced by proinflammatory cytokines, raising the possibility that it can be beneficial in countering autoimmune diseases, such as type 1 diabetes.
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Affiliation(s)
- Christina Dedaki
- Laboratory of Organic Chemistry, Department of Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771 , Greece
| | - Maroula G Kokotou
- Laboratory of Organic Chemistry, Department of Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771 , Greece.,Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California, San Diego , La Jolla, San Diego , California 92093-0601 , United States
| | - Varnavas D Mouchlis
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California, San Diego , La Jolla, San Diego , California 92093-0601 , United States
| | - Dimitris Limnios
- Laboratory of Organic Chemistry, Department of Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771 , Greece.,Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California, San Diego , La Jolla, San Diego , California 92093-0601 , United States
| | | | - Carol T Mu
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California, San Diego , La Jolla, San Diego , California 92093-0601 , United States
| | | | - Victoria Magrioti
- Laboratory of Organic Chemistry, Department of Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771 , Greece
| | - Edward A Dennis
- Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine , University of California, San Diego , La Jolla, San Diego , California 92093-0601 , United States
| | - George Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771 , Greece
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19
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Prasher P, Mudila H, Sharma M, Khati B. Developmental perspectives of the drugs targeting enzyme-instigated inflammation: a mini review. Med Chem Res 2019. [DOI: 10.1007/s00044-019-02315-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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20
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Kumar A, Janes T, Chakraborty S, Daw P, von Wolff N, Carmieli R, Diskin-Posner Y, Milstein D. C−C Bond Formation of Benzyl Alcohols and Alkynes Using a Catalytic Amount of KOt
Bu: Unusual Regioselectivity through a Radical Mechanism. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201812687] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Amit Kumar
- Department of Organic Chemistry; Weizmann Institute of Science; Rehovot 76100 Israel
| | - Trevor Janes
- Department of Organic Chemistry; Weizmann Institute of Science; Rehovot 76100 Israel
| | - Subrata Chakraborty
- Department of Organic Chemistry; Weizmann Institute of Science; Rehovot 76100 Israel
| | - Prosenjit Daw
- Department of Organic Chemistry; Weizmann Institute of Science; Rehovot 76100 Israel
| | - Niklas von Wolff
- Department of Organic Chemistry; Weizmann Institute of Science; Rehovot 76100 Israel
| | - Raanan Carmieli
- Chemical Research Support; Weizmann Institute of Science; Rehovot 76100 Israel
| | - Yael Diskin-Posner
- Chemical Research Support; Weizmann Institute of Science; Rehovot 76100 Israel
| | - David Milstein
- Department of Organic Chemistry; Weizmann Institute of Science; Rehovot 76100 Israel
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21
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Kumar A, Janes T, Chakraborty S, Daw P, von Wolff N, Carmieli R, Diskin-Posner Y, Milstein D. C-C Bond Formation of Benzyl Alcohols and Alkynes Using a Catalytic Amount of KO t Bu: Unusual Regioselectivity through a Radical Mechanism. Angew Chem Int Ed Engl 2019; 58:3373-3377. [PMID: 30605258 DOI: 10.1002/anie.201812687] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Indexed: 01/24/2023]
Abstract
We report a C-C bond-forming reaction between benzyl alcohols and alkynes in the presence of a catalytic amount of KOt Bu to form α-alkylated ketones in which the C=O group is located on the side derived from the alcohol. The reaction proceeds under thermal conditions (125 °C) and produces no waste, making the reaction highly atom efficient, environmentally benign, and sustainable. Based on our mechanistic investigations, we propose that the reaction proceeds through radical pathways.
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Affiliation(s)
- Amit Kumar
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Trevor Janes
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Subrata Chakraborty
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Prosenjit Daw
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Niklas von Wolff
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Raanan Carmieli
- Chemical Research Support, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Yael Diskin-Posner
- Chemical Research Support, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - David Milstein
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
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22
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Guo YP, Tang BS, Liu HL, Huang JJ, Xu Q, Sun QY, Yan XX, Guo JF. Impaired iPLA 2β activity affects iron uptake and storage without iron accumulation: An in vitro study excluding decreased iPLA 2β activity as the cause of iron deposition in PLAN. Brain Res 2019; 1712:25-33. [PMID: 30707893 DOI: 10.1016/j.brainres.2019.01.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/13/2019] [Accepted: 01/27/2019] [Indexed: 01/12/2023]
Abstract
PLA2G6-associated neurodegeneration (PLAN, NBIA2) is the second most common type of neurodegeneration with brain iron accumulation (NBIA), caused by recessive mutations of PLA2G6 gene, which encodes Ca2+-independent phospholipase A2β (iPLA2β). In most PLAN cases, decreased iPLA2β activity and iron deposition was observed meanwhile, and researchers also identified a PLA2G6 mutation family without iron deposition shown by MRI images. This brought us the question of whether decreased iPLA2β activity was the cause of iron deposition in PLAN. In this study, we used S-BEL as the antagonist of iPLA2β to block its activity and used SH-SY5Y cells as the expression system. We incubated SH-SY5Y cells with different concentrations of S-BEL. The results showed that decreased iPLA2β activity led no obvious iron accumulation, while changes of cells state and activation of apoptosis were observed. To further investigate the cause of unchanged iron level, we examined the cellular iron regulatory proteins involved in iron uptake, storage and export. The results were as follows: TfR1 (iron uptake protein) expression was decreased, the expression of ferritin heavy chain and light chain (iron storage protein) was increased. There was no alteration of the expression of DMT1 (iron uptake protein) and FPN1 (iron export protein). Under the condition of decreased iPLA2β activity, there was no obvious iron accumulation but iron uptake activity decreased and iron storage activity increased. Therefore, we speculate that the decreased iPLA2β activity may not be the main reason for iron deposition in PLAN.
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Affiliation(s)
- Yu-Pei Guo
- Center for Brain Disorders Research, Capital Medical University and Beijing Institute of Brain Disorders, Beijing 100069, People's Republic of China; Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Bei-Sha Tang
- Center for Brain Disorders Research, Capital Medical University and Beijing Institute of Brain Disorders, Beijing 100069, People's Republic of China; Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China; National Clinical Research Center for Geriatric Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China; Center for Medical Genetics, Central South University, Changsha 410008, Hunan, People's Republic of China; Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Hong-Li Liu
- Center for Brain Disorders Research, Capital Medical University and Beijing Institute of Brain Disorders, Beijing 100069, People's Republic of China; Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Juan-Juan Huang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Qian Xu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China; National Clinical Research Center for Geriatric Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China; Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Qi-Ying Sun
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China; National Clinical Research Center for Geriatric Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China; Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Xin-Xiang Yan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China; Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China
| | - Ji-Feng Guo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan, People's Republic of China; National Clinical Research Center for Geriatric Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China; Center for Medical Genetics, Central South University, Changsha 410008, Hunan, People's Republic of China; Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha 410008, Hunan, People's Republic of China.
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23
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Triandafillidi I, Tzaras DI, Kokotos CG. Green Organocatalytic Oxidative Methods using Activated Ketones. ChemCatChem 2018. [DOI: 10.1002/cctc.201800013] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ierasia Triandafillidi
- Laboratory of Organic Chemistry; Department of Chemistry; National and Kapodistrian University of Athens, Panepistimiopolis; 15771 Athens Greece
| | - Dimitrios Ioannis Tzaras
- Laboratory of Organic Chemistry; Department of Chemistry; National and Kapodistrian University of Athens, Panepistimiopolis; 15771 Athens Greece
| | - Christoforos G. Kokotos
- Laboratory of Organic Chemistry; Department of Chemistry; National and Kapodistrian University of Athens, Panepistimiopolis; 15771 Athens Greece
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24
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Nikolaou A, Ninou I, Kokotou MG, Kaffe E, Afantitis A, Aidinis V, Kokotos G. Hydroxamic Acids Constitute a Novel Class of Autotaxin Inhibitors that Exhibit in Vivo Efficacy in a Pulmonary Fibrosis Model. J Med Chem 2018; 61:3697-3711. [PMID: 29620892 DOI: 10.1021/acs.jmedchem.8b00232] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Autotaxin (ATX) catalyzes the hydrolysis of lysophosphatidylcholine (LPC) generating the lipid mediator lysophosphatidic acid (LPA). Both ATX and LPA are involved in various pathological inflammatory conditions, including fibrosis and cancer, and have attracted great interest as medicinal targets over the past decade. Thus, the development of novel potent ATX inhibitors is of great importance. We have developed a novel class of ATX inhibitors containing the zinc binding functionality of hydroxamic acid. Such novel hydroxamic acids that incorporate a non-natural δ-amino acid residue exhibit high in vitro inhibitory potency over ATX (IC50 values 50-60 nM). Inhibitor 32, based on δ-norleucine, was tested for its efficacy in a mouse model of pulmonary inflammation and fibrosis induced by bleomycin and exhibited promising efficacy. The novel hydroxamic ATX inhibitors provide excellent tools for the study of the role of the enzyme and could contribute to the development of novel therapeutic agents for the treatment of fibrosis and other chronic inflammatory diseases.
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Affiliation(s)
- Aikaterini Nikolaou
- Laboratory of Organic Chemistry, Department of Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis , Athens 15771 , Greece
| | - Ioanna Ninou
- Division of Immunology , Biomedical Sciences Research Center "Alexander Fleming" , Athens 16672 , Greece
| | - Maroula G Kokotou
- Laboratory of Organic Chemistry, Department of Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis , Athens 15771 , Greece
| | - Eleanna Kaffe
- Division of Immunology , Biomedical Sciences Research Center "Alexander Fleming" , Athens 16672 , Greece
| | | | - Vassilis Aidinis
- Division of Immunology , Biomedical Sciences Research Center "Alexander Fleming" , Athens 16672 , Greece
| | - George Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis , Athens 15771 , Greece
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25
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Sahoo AR, Lalitha G, Murugesh V, Bruneau C, Sharma GVM, Suresh S, Achard M. Ruthenium Phosphine–Pyridone Catalyzed Cross-Coupling of Alcohols To form α-Alkylated Ketones. J Org Chem 2017; 82:10727-10731. [DOI: 10.1021/acs.joc.7b02042] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Apurba R. Sahoo
- UMR
6226, Institut des Sciences Chimiques de Rennes, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Gummidi Lalitha
- Organic
and Biomolecular Chemistry Division, CSIR-IICT, Hyderabad 500 007, India
| | - V. Murugesh
- Organic
and Biomolecular Chemistry Division, CSIR-IICT, Hyderabad 500 007, India
| | - Christian Bruneau
- UMR
6226, Institut des Sciences Chimiques de Rennes, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | | | - Surisetti Suresh
- Organic
and Biomolecular Chemistry Division, CSIR-IICT, Hyderabad 500 007, India
| | - Mathieu Achard
- UMR
6226, Institut des Sciences Chimiques de Rennes, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
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26
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2-Oxoesters: A Novel Class of Potent and Selective Inhibitors of Cytosolic Group IVA Phospholipase A 2. Sci Rep 2017; 7:7025. [PMID: 28765606 PMCID: PMC5539244 DOI: 10.1038/s41598-017-07330-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 06/28/2017] [Indexed: 12/30/2022] Open
Abstract
Cytosolic phospholipase A2 (GIVA cPLA2) is the only PLA2 that exhibits a marked preference for hydrolysis of arachidonic acid containing phospholipid substrates releasing free arachidonic acid and lysophospholipids and giving rise to the generation of diverse lipid mediators involved in inflammatory conditions. Thus, the development of potent and selective GIVA cPLA2 inhibitors is of great importance. We have developed a novel class of such inhibitors based on the 2-oxoester functionality. This functionality in combination with a long aliphatic chain or a chain carrying an appropriate aromatic system, such as the biphenyl system, and a free carboxyl group leads to highly potent and selective GIVA cPLA2 inhibitors (XI(50) values 0.00007–0.00008) and docking studies aid in understanding this selectivity. A methyl 2-oxoester, with a short chain carrying a naphthalene ring, was found to preferentially inhibit the other major intracellular PLA2, the calcium-independent PLA2. In RAW264.7 macrophages, treatment with the most potent 2-oxoester GIVA cPLA2 inhibitor resulted in over 50% decrease in KLA-elicited prostaglandin D2 production. The novel, highly potent and selective GIVA cPLA2 inhibitors provide excellent tools for the study of the role of the enzyme and could contribute to the development of novel therapeutic agents for the treatment of inflammatory diseases.
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27
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Luo X, Cheng C, Tan Z, Li N, Tang M, Yang L, Cao Y. Emerging roles of lipid metabolism in cancer metastasis. Mol Cancer 2017; 16:76. [PMID: 28399876 PMCID: PMC5387196 DOI: 10.1186/s12943-017-0646-3] [Citation(s) in RCA: 379] [Impact Index Per Article: 54.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 04/03/2017] [Indexed: 12/16/2022] Open
Abstract
Cancer cells frequently display fundamentally altered cellular metabolism, which provides the biochemical foundation and directly contributes to tumorigenicity and malignancy. Rewiring of metabolic programmes, such as aerobic glycolysis and increased glutamine metabolism, are crucial for cancer cells to shed from a primary tumor, overcome the nutrient and energy deficit, and eventually survive and form metastases. However, the role of lipid metabolism that confers the aggressive properties of malignant cancers remains obscure. The present review is focused on key enzymes in lipid metabolism associated with metastatic disease pathogenesis. We also address the function of an important membrane structure-lipid raft in mediating tumor aggressive progression. We enumerate and integrate these recent findings into our current understanding of lipid metabolic reprogramming in cancer metastasis accompanied by new and exciting therapeutic implications.
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Affiliation(s)
- Xiangjian Luo
- Key Laboratory of Carcinogenesis and Invasion, Chinese Ministry of Education, Xiangya Hospital, Central South University, Changsha, Hunan, 410078, China. .,Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha, Hunan, 410078, China. .,Key Laboratory of Carcinogenesis, Chinese Ministry of Health, Changsha, Hunan, 410078, China.
| | - Can Cheng
- Key Laboratory of Carcinogenesis and Invasion, Chinese Ministry of Education, Xiangya Hospital, Central South University, Changsha, Hunan, 410078, China.,Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha, Hunan, 410078, China.,Key Laboratory of Carcinogenesis, Chinese Ministry of Health, Changsha, Hunan, 410078, China
| | - Zheqiong Tan
- Key Laboratory of Carcinogenesis and Invasion, Chinese Ministry of Education, Xiangya Hospital, Central South University, Changsha, Hunan, 410078, China.,Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha, Hunan, 410078, China.,Key Laboratory of Carcinogenesis, Chinese Ministry of Health, Changsha, Hunan, 410078, China
| | - Namei Li
- Key Laboratory of Carcinogenesis and Invasion, Chinese Ministry of Education, Xiangya Hospital, Central South University, Changsha, Hunan, 410078, China.,Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha, Hunan, 410078, China.,Key Laboratory of Carcinogenesis, Chinese Ministry of Health, Changsha, Hunan, 410078, China
| | - Min Tang
- Key Laboratory of Carcinogenesis and Invasion, Chinese Ministry of Education, Xiangya Hospital, Central South University, Changsha, Hunan, 410078, China.,Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha, Hunan, 410078, China.,Key Laboratory of Carcinogenesis, Chinese Ministry of Health, Changsha, Hunan, 410078, China
| | - Lifang Yang
- Key Laboratory of Carcinogenesis and Invasion, Chinese Ministry of Education, Xiangya Hospital, Central South University, Changsha, Hunan, 410078, China.,Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha, Hunan, 410078, China.,Key Laboratory of Carcinogenesis, Chinese Ministry of Health, Changsha, Hunan, 410078, China
| | - Ya Cao
- Key Laboratory of Carcinogenesis and Invasion, Chinese Ministry of Education, Xiangya Hospital, Central South University, Changsha, Hunan, 410078, China. .,Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha, Hunan, 410078, China. .,Key Laboratory of Carcinogenesis, Chinese Ministry of Health, Changsha, Hunan, 410078, China.
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28
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Smyrniotou A, Kokotou MG, Mouchlis VD, Barbayianni E, Kokotos G, Dennis EA, Constantinou-Kokotou V. 2-Oxoamides based on dipeptides as selective calcium-independent phospholipase A 2 inhibitors. Bioorg Med Chem 2016; 25:926-940. [PMID: 28034646 DOI: 10.1016/j.bmc.2016.12.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 12/04/2016] [Accepted: 12/05/2016] [Indexed: 11/18/2022]
Abstract
Calcium-independent phospholipase A2 (GVIA iPLA2) has recently attracted interest as a medicinal target. The number of known GVIA iPLA2 inhibitors is limited to a handful of synthetic compounds (bromoenol lactone and polyfluoroketones). To expand the chemical diversity, a variety of 2-oxoamides based on dipeptides and ether dipeptides were synthesized and studied for their in vitro inhibitory activity on human GVIA iPLA2 and their selectivity over the other major intracellular GIVA cPLA2 and the secreted GV sPLA2. Structure-activity relationship studies revealed the first 2-oxoamide derivative (GK317), which presents potent inhibition of GVIA iPLA2 (XI(50) value of 0.007) and at the same time significant selectivity over GIVA cPLA2 and GV sPLA2.
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Affiliation(s)
- Anneta Smyrniotou
- Chemical Laboratories, Agricultural University of Athens, Iera Odos 75, Athens 11855, Greece
| | - Maroula G Kokotou
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece; Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0601, USA
| | - Varnavas D Mouchlis
- Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0601, USA
| | - Efrosini Barbayianni
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - George Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - Edward A Dennis
- Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0601, USA.
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29
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Antonopoulou G, Magrioti V, Kokotou MG, Nikolaou A, Barbayianni E, Mouchlis VD, Dennis EA, Kokotos G. 2-Oxoamide inhibitors of cytosolic group IVA phospholipase A2 with reduced lipophilicity. Bioorg Med Chem 2016; 24:4544-4554. [PMID: 27522578 PMCID: PMC5014611 DOI: 10.1016/j.bmc.2016.07.057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 12/31/2022]
Abstract
Cytosolic GIVA phospholipase A2 (GIVA cPLA2) initiates the eicosanoid pathway of inflammation and thus inhibitors of this enzyme constitute novel potential agents for the treatment of inflammatory diseases. Traditionally, GIVA cPLA2 inhibitors have suffered systemically from high lipophilicity. We have developed a variety of long chain 2-oxoamides as inhibitors of GIVA PLA2. Among them, AX048 was found to produce a potent analgesic effect. We have now reduced the lipophilicity of AX048 by replacing the long aliphatic chain with a chain containing an ether linked aromatic ring with in vitro inhibitory activities similar to AX048.
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Affiliation(s)
- Georgia Antonopoulou
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece; Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, Athens, Greece
| | - Victoria Magrioti
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - Maroula G Kokotou
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - Aikaterini Nikolaou
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - Efrosini Barbayianni
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
| | - Varnavas D Mouchlis
- Department of Chemistry and Biochemistry, School of Medicine, MC 0601, University of California, San Diego, La Jolla, CA 92093-0601, USA; Department of Pharmacology, School of Medicine, MC 0601, University of California, San Diego, La Jolla, CA 92093-0601, USA
| | - Edward A Dennis
- Department of Chemistry and Biochemistry, School of Medicine, MC 0601, University of California, San Diego, La Jolla, CA 92093-0601, USA; Department of Pharmacology, School of Medicine, MC 0601, University of California, San Diego, La Jolla, CA 92093-0601, USA.
| | - George Kokotos
- Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece.
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30
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Dennis EA. Liberating Chiral Lipid Mediators, Inflammatory Enzymes, and LIPID MAPS from Biological Grease. J Biol Chem 2016; 291:24431-24448. [PMID: 27555328 DOI: 10.1074/jbc.x116.723791] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
In 1970, it was well accepted that the central role of lipids was in energy storage and metabolism, and it was assumed that amphipathic lipids simply served a passive structural role as the backbone of biological membranes. As a result, the scientific community was focused on nucleic acids, proteins, and carbohydrates as information-containing molecules. It took considerable effort until scientists accepted that lipids also "encode" specific and unique biological information and play a central role in cell signaling. Along with this realization came the recognition that the enzymes that act on lipid substrates residing in or on membranes and micelles must also have important signaling roles, spurring curiosity into their potentially unique modes of action differing from those acting on water-soluble substrates. This led to the creation of the concept of "surface dilution kinetics" for describing the mechanism of enzymes acting on lipid substrates, as well as the demonstration that lipid enzymes such as phospholipase A2 (PLA2) contain allosteric activator sites for specific phospholipids as well as for membranes. As our understanding of phospholipases advanced, so did the understanding that many of the lipids released by these enzymes are chiral information-containing signaling molecules; for example, PLA2 regulates the generation of precursors for the biosynthesis of eicosanoids and other bioactive lipid mediators of inflammation and resolution underlying disease progression. The creation of the LIPID MAPS initiative in 2003 and the ensuing development of the lipidomics field have revealed that lipid metabolites are central to human metabolism. Today lipids are recognized as key mediators of health and disease as we enter a new era of biomarkers and personalized medicine. This article is my personal "reflection" on these scientific advances.
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Affiliation(s)
- Edward A Dennis
- From the Department of Chemistry and Biochemistry and Department of Pharmacology, School of Medicine, University of California at San Diego, La Jolla, California 92093-0601.
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31
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Sanz-Marco A, Blay G, Muñoz MC, Pedro JR. Catalytic Enantioselective Conjugate Alkynylation of α,β-Unsaturated 1,1,1-Trifluoromethyl Ketones with Terminal Alkynes. Chemistry 2016; 22:10057-64. [DOI: 10.1002/chem.201601303] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Amparo Sanz-Marco
- Department de Química Orgànica-Facultat de Química; Universitat de València; C/Dr. Moliner 50 46100 Burjasso Spain
| | - Gonzalo Blay
- Department de Química Orgànica-Facultat de Química; Universitat de València; C/Dr. Moliner 50 46100 Burjasso Spain
| | - M. Carmen Muñoz
- Departament de Física Aplicada; Universitat Politècnica de València; Camí de Vera s/n 46022 València Spain
| | - José R. Pedro
- Department de Química Orgànica-Facultat de Química; Universitat de València; C/Dr. Moliner 50 46100 Burjasso Spain
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32
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Computer-aided drug design guided by hydrogen/deuterium exchange mass spectrometry: A powerful combination for the development of potent and selective inhibitors of Group VIA calcium-independent phospholipase A 2. Bioorg Med Chem 2016; 24:4801-4811. [PMID: 27320659 DOI: 10.1016/j.bmc.2016.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 05/05/2016] [Accepted: 05/09/2016] [Indexed: 11/20/2022]
Abstract
Potent and selective inhibitors for phospholipases A2 (PLA2) are useful for studying their intracellular functions. PLA2 enzymes liberate arachidonic acid from phospholipids activating eicosanoid pathways that involve cyclooxygenase (COX) and lipoxygenase (LOX) leading to inflammation. Anti-inflammatory drugs target COX and LOX; thus, PLA2 can also be targeted to diminish inflammation at an earlier stage in the process. This paper describes the employment of enzymatic assays, hydrogen/deuterium exchange mass spectrometry (DXMS) and computational chemistry to develop PLA2 inhibitors. Beta-thioether trifluoromethylketones (TFKs) were screened against human GVIA calcium-independent, GIVA cytosolic and GV secreted PLA2s. These compounds exhibited inhibition toward Group VIA calcium-independent PLA2 (GVIA iPLA2), with the most potent and selective inhibitor 3 (OTFP) obtaining an XI(50) of 0.0002 mole fraction (IC50 of 110nM). DXMS binding experiments in the presence of OTFP revealed the peptide regions of GVIA iPLA2 that interact with the inhibitor. Molecular docking and dynamics simulations in the presence of a membrane were guided by the DXMS data in order to identify the binding mode of OTFP. Clustering analysis showed the binding mode of OTFP that occupied 70% of the binding modes occurring during the simulation. The resulted 3D complex was used for docking studies and a structure-activity relationship (SAR) was established. This paper describes a novel multidisciplinary approach in which a 3D complex of GVIA iPLA2 with an inhibitor is reported and validated by experimental data. The SAR showed that the sulfur atom is vital for the potency of beta-thioether analogues, while the hydrophobic chain is important for selectivity. This work constitutes the foundation for further design, synthesis and inhibition studies in order to develop new beta-thioether analogues that are potent and selective for GVIA iPLA2 exclusively.
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33
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Mouchlis VD, Limnios D, Kokotou MG, Barbayianni E, Kokotos G, McCammon JA, Dennis EA. Development of Potent and Selective Inhibitors for Group VIA Calcium-Independent Phospholipase A2 Guided by Molecular Dynamics and Structure-Activity Relationships. J Med Chem 2016; 59:4403-14. [PMID: 27087127 DOI: 10.1021/acs.jmedchem.6b00377] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The development of inhibitors for phospholipase A2 (PLA2) is important in elucidating the enzymes implication in various biological pathways. PLA2 enzymes are an important pharmacological target implicated in various inflammatory diseases. Computational chemistry, organic synthesis, and in vitro assays were employed to develop potent and selective inhibitors for group VIA calcium-independent PLA2. A set of fluoroketone inhibitors was studied for their binding mode with two human cytosolic PLA2 enzymes: group IVA cPLA2 and group VIA iPLA2. New compounds were synthesized and assayed toward three major PLA2s. This study led to the development of four potent and selective thioether fluoroketone inhibitors as well as a thioether keto-1,2,4-oxadiazole inhibitor for GVIA iPLA2, which will serve as lead compounds for future development and studies. The keto-1,2,4-oxadiazole functionality with a thioether is a novel structure, and it will be used as a lead to develop inhibitors with higher potency and selectivity toward GVIA iPLA2.
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Affiliation(s)
- Varnavas D Mouchlis
- Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego , La Jolla, California 92093-0601, United States
| | - Dimitris Limnios
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771, Greece
| | - Maroula G Kokotou
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771, Greece
| | - Efrosini Barbayianni
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771, Greece
| | - George Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis, Athens 15771, Greece
| | - J Andrew McCammon
- Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego , La Jolla, California 92093-0601, United States
| | - Edward A Dennis
- Department of Pharmacology and Department of Chemistry and Biochemistry, School of Medicine, University of California, San Diego , La Jolla, California 92093-0601, United States
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34
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Membrane and inhibitor interactions of intracellular phospholipases A2. Adv Biol Regul 2015; 61:17-24. [PMID: 26774606 DOI: 10.1016/j.jbior.2015.11.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 11/19/2015] [Accepted: 11/20/2015] [Indexed: 02/06/2023]
Abstract
Studying phospholipases A2 (PLA2s) is a challenging task since they act on membrane-like aggregated substrates and not on monomeric phospholipids. Multidisciplinary approaches that include hydrogen/deuterium exchange mass spectrometry (DXMS) and computational techniques have been employed with great success in order to address important questions about the mode of interactions of PLA2 enzymes with membranes, phospholipid substrates and inhibitors. Understanding the interactions of PLA2s is crucial since these enzymes are the upstream regulators of the eicosanoid pathway liberating free arachidonic acid (AA) and other polyunsaturated fatty acids (PUFA). The liberation of AA by PLA2 enzymes sets off a cascade of molecular events that involves downstream regulators such as cyclooxygenase (COX) and lipoxygenase (LOX) metabolites leading to inflammation. Aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) work by inhibiting COX, while Zileuton inhibits LOX and both rely on PLA2 enzymes to provide them with AA. That means PLA2 enzymes can potentially also be targeted to diminish inflammation at an earlier point in the process. In this review we describe extensive efforts reported in the past to define the interactions of PLA2 enzymes with membranes, substrate phospholipids and inhibitors using DXMS, molecular docking, and molecular dynamics (MD) simulations.
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35
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Wang R, Ma J, Li F. Synthesis of a-Alkylated Ketones via Tandem Acceptorless Dehydrogenation/a-Alkylation from Secondary and Primary Alcohols Catalyzed by Metal–Ligand Bifunctional Iridium Complex [Cp*Ir(2,2′-bpyO)(H2O)]. J Org Chem 2015; 80:10769-76. [DOI: 10.1021/acs.joc.5b01975] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rongzhou Wang
- School of Chemical Engineering, Nanjing University of Science & Technology, Nanjing 210094, People’s Republic of China
| | - Juan Ma
- School of Chemical Engineering, Nanjing University of Science & Technology, Nanjing 210094, People’s Republic of China
| | - Feng Li
- School of Chemical Engineering, Nanjing University of Science & Technology, Nanjing 210094, People’s Republic of China
- State
Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, People’s Republic of China
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36
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Ong WY, Farooqui T, Kokotos G, Farooqui AA. Synthetic and natural inhibitors of phospholipases A2: their importance for understanding and treatment of neurological disorders. ACS Chem Neurosci 2015; 6:814-31. [PMID: 25891385 DOI: 10.1021/acschemneuro.5b00073] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Phospholipases A2 (PLA2) are a diverse group of enzymes that hydrolyze membrane phospholipids into arachidonic acid and lysophospholipids. Arachidonic acid is metabolized to eicosanoids (prostaglandins, leukotrienes, thromboxanes), and lysophospholipids are converted to platelet-activating factors. These lipid mediators play critical roles in the initiation, maintenance, and modulation of neuroinflammation and oxidative stress. Neurological disorders including excitotoxicity; traumatic nerve and brain injury; cerebral ischemia; Alzheimer's disease; Parkinson's disease; multiple sclerosis; experimental allergic encephalitis; pain; depression; bipolar disorder; schizophrenia; and autism are characterized by oxidative stress, inflammatory reactions, alterations in phospholipid metabolism, accumulation of lipid peroxides, and increased activities of brain phospholipase A2 isoforms. Several old and new synthetic inhibitors of PLA2, including fatty acid trifluoromethyl ketones; methyl arachidonyl fluorophosphonate; bromoenol lactone; indole-based inhibitors; pyrrolidine-based inhibitors; amide inhibitors, 2-oxoamides; 1,3-disubstituted propan-2-ones and polyfluoroalkyl ketones as well as phytochemical based PLA2 inhibitors including curcumin, Ginkgo biloba and Centella asiatica extracts have been discovered and used for the treatment of neurological disorders in cell culture and animal model systems. The purpose of this review is to summarize information on selective and potent synthetic inhibitors of PLA2 as well as several PLA2 inhibitors from plants, for treatment of oxidative stress and neuroinflammation associated with the pathogenesis of neurological disorders.
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Affiliation(s)
- Wei-Yi Ong
- Department
of Anatomy, National University of Singapore, Singapore 119260, Singapore
| | - Tahira Farooqui
- Department
of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
| | - George Kokotos
- Laboratory
of Organic Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis,
Athens 15771, Greece
| | - Akhlaq A. Farooqui
- Department
of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
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37
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Panferova LI, Miloserdov FM, Lishchynskyi A, Martínez Belmonte M, Benet-Buchholz J, Grushin VV. Well-Defined CuC2F5Complexes and Pentafluoroethylation of Acid Chlorides. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201500341] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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38
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Panferova LI, Miloserdov FM, Lishchynskyi A, Martínez Belmonte M, Benet-Buchholz J, Grushin VV. Well-Defined CuC2F5Complexes and Pentafluoroethylation of Acid Chlorides. Angew Chem Int Ed Engl 2015; 54:5218-22. [DOI: 10.1002/anie.201500341] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Indexed: 01/28/2023]
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39
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Kokotos G, Feuerherm AJ, Barbayianni E, Shah I, Sæther M, Magrioti V, Nguyen T, Constantinou-Kokotou V, Dennis EA, Johansen B. Inhibition of group IVA cytosolic phospholipase A2 by thiazolyl ketones in vitro, ex vivo, and in vivo. J Med Chem 2014; 57:7523-35. [PMID: 25152071 DOI: 10.1021/jm500192s] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Group IVA cytosolic phospholipase A2 (GIVA cPLA2) is the rate-limiting provider of pro-inflammatory mediators in many tissues and is thus an attractive target for the development of novel anti-inflammatory agents. In this work, we present the synthesis of new thiazolyl ketones and the study of their activities in vitro, in cells, and in vivo. Within this series of compounds, methyl 2-(2-(4-octylphenoxy)acetyl)thiazole-4-carboxylate (GK470) was found to be the most potent inhibitor of GIVA cPLA2, exhibiting an XI(50) value of 0.011 mole fraction in a mixed micelle assay and an IC50 of 300 nM in a vesicle assay. In a cellular assay using SW982 fibroblast-like synoviocytes, it suppressed the release of arachidonic acid with an IC50 value of 0.6 μM. In a prophylactic collagen-induced arthritis model, it exhibited an anti-inflammatory effect comparable to the reference drug methotrexate, whereas in a therapeutic model, it showed results comparable to those of the reference drug Enbrel. In both models, it significantly reduced plasma PGE2 levels.
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Affiliation(s)
- George Kokotos
- Laboratory of Organic Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis , Athens 15771, Greece
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40
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Hamlin TA, Lazarus GML, Kelly CB, Leadbeater NE. A Continuous-Flow Approach to 3,3,3-Trifluoromethylpropenes: Bringing Together Grignard Addition, Peterson Elimination, Inline Extraction, and Solvent Switching. Org Process Res Dev 2014. [DOI: 10.1021/op500190j] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Trevor A. Hamlin
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut 06269-3060, United States
| | - Gillian M. L. Lazarus
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut 06269-3060, United States
| | - Christopher B. Kelly
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut 06269-3060, United States
| | - Nicholas E. Leadbeater
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut 06269-3060, United States
- Department of Community Medicine & Health Care, University of Connecticut Health Center, The Exchange, 263 Farmington Avenue, Farmington, Connecticut 06030, United States
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41
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Ma J, Wang N, Li F. One-Pot Sequential Catalytic Hydration of Alkynes and α-Alkylation with Alcohols for the Synthesis of α-Alkylated Ketones. ASIAN J ORG CHEM 2014. [DOI: 10.1002/ajoc.201402055] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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42
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Scott SA, Mathews TP, Ivanova PT, Lindsley CW, Brown HA. Chemical modulation of glycerolipid signaling and metabolic pathways. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1841:1060-84. [PMID: 24440821 DOI: 10.1016/j.bbalip.2014.01.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/06/2014] [Accepted: 01/07/2014] [Indexed: 01/04/2023]
Abstract
Thirty years ago, glycerolipids captured the attention of biochemical researchers as novel cellular signaling entities. We now recognize that these biomolecules occupy signaling nodes critical to a number of physiological and pathological processes. Thus, glycerolipid-metabolizing enzymes present attractive targets for new therapies. A number of fields-ranging from neuroscience and cancer to diabetes and obesity-have elucidated the signaling properties of glycerolipids. The biochemical literature teems with newly emerging small molecule inhibitors capable of manipulating glycerolipid metabolism and signaling. This ever-expanding pool of chemical modulators appears daunting to those interested in exploiting glycerolipid-signaling pathways in their model system of choice. This review distills the current body of literature surrounding glycerolipid metabolism into a more approachable format, facilitating the application of small molecule inhibitors to novel systems. This article is part of a Special Issue entitled Tools to study lipid functions.
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Affiliation(s)
- Sarah A Scott
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Thomas P Mathews
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Pavlina T Ivanova
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37235, USA
| | - H Alex Brown
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Biochemistry, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37235, USA.
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43
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Kohn BL, Rovis T. Cobaltate anion couples terminal dienes with trifluoroacetic anhydride: a direct fluoroacylation of 1,3-dienes. Chem Sci 2014. [DOI: 10.1039/c4sc00743c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Perfluoroketones are useful products and intermediates in medicinal and materials chemistry.
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Affiliation(s)
- Benjamin L. Kohn
- Department of Chemistry
- Colorado State University
- Fort Collins, USA
| | - Tomislav Rovis
- Department of Chemistry
- Colorado State University
- Fort Collins, USA
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Kelly CB, Mercadante MA, Leadbeater NE. Trifluoromethyl ketones: properties, preparation, and application. Chem Commun (Camb) 2013; 49:11133-48. [PMID: 24162741 DOI: 10.1039/c3cc46266h] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Trifluoromethyl ketones (TFMKs) are exceedingly valuable synthetic targets in their own right and as synthons in the construction of fluorinated pharmacons. This Feature Article provides an overview of the properties of TFMKs, an in-depth discussion of the methods available for their synthesis, and two illustrative examples of their application as key intermediates in medicinal chemistry.
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Affiliation(s)
- Christopher B Kelly
- Department of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, CT 06269, USA.
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45
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Magrioti V, Nikolaou A, Smyrniotou A, Shah I, Constantinou-Kokotou V, Dennis EA, Kokotos G. New potent and selective polyfluoroalkyl ketone inhibitors of GVIA calcium-independent phospholipase A2. Bioorg Med Chem 2013; 21:5823-9. [PMID: 23916152 DOI: 10.1016/j.bmc.2013.07.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 07/06/2013] [Indexed: 10/26/2022]
Abstract
Group VIA calcium-independent phospholipase A2 (GVIA iPLA2) has recently emerged as an important pharmaceutical target. Selective and potent GVIA iPLA2 inhibitors can be used to study its role in various neurological disorders. In the current work, we explore the significance of the introduction of a substituent in previously reported potent GVIA iPLA2 inhibitors. 1,1,1,2,2-Pentafluoro-7-(4-methoxyphenyl)heptan-3-one (GK187) is the most potent and selective GVIA iPLA2 inhibitor ever reported with a XI(50) value of 0.0001, and with no significant inhibition against GIVA cPLA2 or GV sPLA2. We also compare the inhibition of two difluoromethyl ketones on GVIA iPLA2, GIVA cPLA2, and GV sPLA2.
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Affiliation(s)
- Victoria Magrioti
- Laboratory of Organic Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis, Greece
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Saab-Aoudé S, Bron AM, Creuzot-Garcher CP, Bretillon L, Acar N. A mouse model of in vivo chemical inhibition of retinal calcium-independent phospholipase A2 (iPLA2). Biochimie 2013; 95:903-11. [DOI: 10.1016/j.biochi.2012.12.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 12/11/2012] [Indexed: 10/27/2022]
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47
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Han C, Salyer AE, Kim EH, Jiang X, Jarrard RE, Powers MS, Kirchhoff AM, Salvador TK, Chester JA, Hockerman GH, Colby DA. Evaluation of difluoromethyl ketones as agonists of the γ-aminobutyric acid type B (GABAB) receptor. J Med Chem 2013; 56:2456-65. [PMID: 23428109 DOI: 10.1021/jm301805e] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The design, synthesis, biological evaluation, and in vivo studies of difluoromethyl ketones as GABAB agonists that are not structurally analogous to known GABAB agonists, such as baclofen or 3-aminopropyl phosphinic acid, are presented. The difluoromethyl ketones were assembled in three synthetic steps using a trifluoroacetate-release aldol reaction. Following evaluation at clinically relevant GABA receptors, we have identified a difluoromethyl ketone that is a potent GABAB agonist, obtained its X-ray structure, and presented preliminary in vivo data in alcohol-preferring mice. The behavioral studies in mice demonstrated that this compound tended to reduce the acoustic startle response, which is consistent with an anxiolytic profile. Structure-activity investigations determined that replacing the fluorines of the difluoromethyl ketone with hydrogens resulted in an inactive analogue. Resolution of the individual enantiomers of the difluoromethyl ketone provided a compound with full biological activity at concentrations less than an order of magnitude greater than the pharmaceutical, baclofen.
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Affiliation(s)
- Changho Han
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, USA
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48
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Rudzinski DM, Kelly CB, Leadbeater NE. A Weinreb amide approach to the synthesis of trifluoromethylketones. Chem Commun (Camb) 2013; 48:9610-2. [PMID: 22911019 DOI: 10.1039/c2cc35037h] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel route to access trifluoromethylketones (TFMKs) from Weinreb amides is reported. This represents the first documented case of the Ruppert-Prakash reagent (TMS-CF(3)) reacting in a constructive manner with an amide and enables synthesis of TMFKs without risk of over-trifluoromethylation.
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Affiliation(s)
- DiAndra M Rudzinski
- Department of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, CT 06269, USA
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49
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Magrioti V, Kokotos G. Phospholipase A2inhibitors for the treatment of inflammatory diseases: a patent review (2010 – present). Expert Opin Ther Pat 2013; 23:333-44. [DOI: 10.1517/13543776.2013.754425] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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50
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Kelly CB, Mercadante MA, Hamlin TA, Fletcher MH, Leadbeater NE. Oxidation of α-Trifluoromethyl Alcohols Using a Recyclable Oxoammonium Salt. J Org Chem 2012; 77:8131-41. [DOI: 10.1021/jo301477s] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Christopher B. Kelly
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut
06269-3060, United States
| | - Michael A. Mercadante
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut
06269-3060, United States
| | - Trevor A. Hamlin
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut
06269-3060, United States
| | - Madison H. Fletcher
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut
06269-3060, United States
| | - Nicholas E. Leadbeater
- Department
of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, Connecticut
06269-3060, United States
- Department of Community Medicine & Health Care, University of Connecticut Health Center, The Exchange, 263 Farmington Avenue, Farmington, Connecticut 06030, United States
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