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Bhattarai S, Devkota S, Wolfe MS. Design of Transmembrane Mimetic Structural Probes to Trap Different Stages of γ-Secretase-Substrate Interaction. J Med Chem 2021; 64:15367-15378. [PMID: 34647731 DOI: 10.1021/acs.jmedchem.1c01395] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The transmembrane domain (TMD) of the amyloid precursor protein of Alzheimer's disease is cut processively by γ-secretase through endoproteolysis and tricarboxypeptidase "trimming". We recently developed a prototype substrate TMD mimetic for structural analysis-composed of a helical peptide inhibitor linked to a transition-state analogue-that simultaneously engages a substrate exosite and the active site and is pre-organized to trap the carboxypeptidase transition state. Here, we developed variants of this prototype designed to allow visualization of transition states for endoproteolysis, TMD helix unwinding, and lateral gating of the substrate, identifying potent inhibitors for each class. These TMD mimetics exhibited non-competitive inhibition and occupy both the exosite and the active site, as demonstrated by inhibitor cross-competition experiments and photoaffinity probe binding assays. The new probes should be important structural tools for trapping different stages of substrate recognition and processing via ongoing cryo-electron microscopy with γ-secretase, ultimately aiding rational drug design.
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Affiliation(s)
- Sanjay Bhattarai
- Department of Medicinal Chemistry, University of Kansas, Lawrence, 66045 Kansas, United States
| | - Sujan Devkota
- Department of Medicinal Chemistry, University of Kansas, Lawrence, 66045 Kansas, United States
| | - Michael S Wolfe
- Department of Medicinal Chemistry, University of Kansas, Lawrence, 66045 Kansas, United States
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2
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Lerman E, Levinger S, Albeck A. Optically Active Functionalized Building Blocks for Peptidyl Olefin Peptidomimetics. ChemistrySelect 2021. [DOI: 10.1002/slct.202102058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ekaterina Lerman
- The Julius Spokojny Bioorganic Chemistry Laboratory Department of Chemistry Bar Ilan University Ramat Gan 5290002 Israel
| | - Shlomo Levinger
- The Julius Spokojny Bioorganic Chemistry Laboratory Department of Chemistry Bar Ilan University Ramat Gan 5290002 Israel
| | - Amnon Albeck
- The Julius Spokojny Bioorganic Chemistry Laboratory Department of Chemistry Bar Ilan University Ramat Gan 5290002 Israel
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3
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Santiago Á, Guzmán-Ocampo DC, Aguayo-Ortiz R, Dominguez L. Characterizing the Chemical Space of γ-Secretase Inhibitors and Modulators. ACS Chem Neurosci 2021; 12:2765-2775. [PMID: 34291906 DOI: 10.1021/acschemneuro.1c00313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
γ-Secretase (GS) is one of the most attractive molecular targets for the treatment of Alzheimer's disease (AD). Its key role in the final step of amyloid-β peptides generation and its relationship in the cascade of events for disease development have caught the attention of many pharmaceutical groups. Over the past years, different inhibitors and modulators have been evaluated as promising therapeutics against AD. However, despite the great chemical diversity of the reported compounds, a global classification and visual representation of the chemical space for GS inhibitors and modulators remain unavailable. In the present work, we carried out a two-dimensional (2D) chemical space analysis from different classes and subclasses of GS inhibitors and modulators based on their structural similarity. Along with the novel structural information available for GS complexes, our analysis opens the possibility to identify compounds with high molecular similarity, critical to finding new chemical structures through the optimization of existing compounds and relating them with a potential binding site.
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Affiliation(s)
- Ángel Santiago
- Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Dulce C. Guzmán-Ocampo
- Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Rodrigo Aguayo-Ortiz
- Departamento de Farmacia, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Laura Dominguez
- Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
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Mei H, Han J, Klika KD, Izawa K, Sato T, Meanwell NA, Soloshonok VA. Applications of fluorine-containing amino acids for drug design. Eur J Med Chem 2019; 186:111826. [PMID: 31740056 DOI: 10.1016/j.ejmech.2019.111826] [Citation(s) in RCA: 124] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/21/2019] [Accepted: 10/26/2019] [Indexed: 01/26/2023]
Abstract
Fluorine-containing amino acids are becoming increasingly prominent in new drugs due to two general trends in the modern pharmaceutical industry. Firstly, the growing acceptance of peptides and modified peptides as drugs; and secondly, fluorine editing has become a prevalent protocol in drug-candidate optimization. Accordingly, fluorine-containing amino acids represent one of the more promising and rapidly developing areas of research in organic, bio-organic and medicinal chemistry. The goal of this Review article is to highlight the current state-of-the-art in this area by profiling 42 selected compounds that combine fluorine and amino acid structural elements. The compounds under discussion represent pharmaceutical drugs currently on the market, or in clinical trials as well as examples of drug-candidates that although withdrawn from development had a significant impact on the progress of medicinal chemistry and/or provided a deeper understanding of the nature and mechanism of biological action. For each compound, we present features of biological activity, a brief history of the design principles and the development of the synthetic approach, focusing on the source of tailor-made amino acid structures and fluorination methods. General aspects of the medicinal chemistry of fluorine-containing amino acids and synthetic methodology are briefly discussed.
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Affiliation(s)
- Haibo Mei
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Jianlin Han
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Karel D Klika
- Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
| | - Kunisuke Izawa
- Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, 533-0024, Japan.
| | - Tatsunori Sato
- Hamari Chemicals Ltd., 1-4-29 Kunijima, Higashi-Yodogawa-ku, Osaka, 533-0024, Japan
| | - Nicholas A Meanwell
- Department of Discovery Chemistry, Bristol-Myers Squibb Research and Development, PO Box 4000, Princeton, NJ, 08543-4000, United States.
| | - Vadim A Soloshonok
- Department of Organic Chemistry I, University of the Basque Country UPV/EHU, Paseo Manuel Lardizábal 3, 20018, San Sebastián, Spain; IKERBASQUE, Basque Foundation for Science, María Díaz de Haro 3, Plaza Bizkaia, 48013, Bilbao, Spain.
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5
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Ajmani S, Janardhan S, Viswanadhan VN. Toward a general predictive QSAR model for gamma-secretase inhibitors. Mol Divers 2013; 17:421-34. [DOI: 10.1007/s11030-013-9441-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 03/26/2013] [Indexed: 10/26/2022]
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6
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Bulic B, Ness J, Hahn S, Rennhack A, Jumpertz T, Weggen S. Chemical Biology, Molecular Mechanism and Clinical Perspective of γ-Secretase Modulators in Alzheimer's Disease. Curr Neuropharmacol 2012; 9:598-622. [PMID: 22798753 PMCID: PMC3391656 DOI: 10.2174/157015911798376352] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2010] [Revised: 10/25/2010] [Accepted: 11/01/2010] [Indexed: 12/25/2022] Open
Abstract
Comprehensive evidence supports that oligomerization and accumulation of amyloidogenic Aβ42 peptides in brain is crucial in the pathogenesis of both familial and sporadic forms of Alzheimer's disease. Imaging studies indicate that the buildup of Aβ begins many years before the onset of clinical symptoms, and that subsequent neurodegeneration and cognitive decline may proceed independently of Aβ. This implies the necessity for early intervention in cognitively normal individuals with therapeutic strategies that prioritize safety. The aspartyl protease γ-secretase catalyses the last step in the cellular generation of Aβ42 peptides, and is a principal target for anti-amyloidogenic intervention strategies. Due to the essential role of γ-secretase in the NOTCH signaling pathway, overt mechanism-based toxicity has been observed with the first generation of γ-secretase inhibitors, and safety of this approach has been questioned. However, two new classes of small molecules, γ-secretase modulators (GSMs) and NOTCH-sparing γ-secretase inhibitors, have revitalized γ-secretase as a drug target in AD. GSMs are small molecules that cause a product shift from Aβ42 towards shorter and less toxic Ab peptides. Importantly, GSMs spare other physiologically important substrates of the γ-secretase complex like NOTCH. Recently, GSMs with nanomolar potency and favorable in vivo properties have been described. In this review, we summarize the knowledge about the unusual proteolytic activity of γ-secretase, and the chemical biology, molecular mechanisms and clinical perspective of compounds that target the γ-secretase complex, with a particular focus on GSMs.
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Affiliation(s)
- Bruno Bulic
- Research Group Chemical Biology of Neurodegenerative Diseases, Center of Advanced European Studies and Research, D-53175 Bonn, Germany
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7
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Grün A, Blastik Z, Drahos L, Keglevich G. Microwave-assisted alkylation of diethyl ethoxycarbonylmethylphosphonate under solventless conditions. HETEROATOM CHEMISTRY 2012. [DOI: 10.1002/hc.21009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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8
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Mirilashvili S, Chasid-Rubinstein N, Albeck A. Optically Active N- and C-Terminal Building Blocks for the Synthesis of Peptidyl Olefin Peptidomimetics. European J Org Chem 2010. [DOI: 10.1002/ejoc.201000539] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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9
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Kreft AF, Martone R, Porte A. Recent advances in the identification of gamma-secretase inhibitors to clinically test the Abeta oligomer hypothesis of Alzheimer's disease. J Med Chem 2009; 52:6169-88. [PMID: 19694467 DOI: 10.1021/jm900188z] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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10
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Holloway MK, Hunt P, McGaughey GB. Structure and modeling in the design of β- and γ-secretase inhibitors. Drug Dev Res 2009. [DOI: 10.1002/ddr.20291] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Mirilashvili S, Chasid-Rubinstein N, Albeck A. Optically Active γ-Hydroxy Sulfone Julia Reagents for the Synthesis of Peptidyl Olefin Peptidomimetics. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800334] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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12
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Prasad CVC, Zheng M, Vig S, Bergstrom C, Smith DW, Gao Q, Yeola S, Polson CT, Corsa JA, Guss VL, Loo A, Wang J, Sleczka BG, Dangler C, Robertson BJ, Hendrick JP, Roberts SB, Barten DM. Discovery of (S)-2-((S)-2-(3,5-difluorophenyl)-2-hydroxyacetamido)-N-((S,Z)-3-methyl-4-oxo-4,5-dihydro-3H-benzo[d][1,2]diazepin-5-yl)propanamide (BMS-433796): a gamma-secretase inhibitor with Abeta lowering activity in a transgenic mouse model of Alzheimer's disease. Bioorg Med Chem Lett 2007; 17:4006-11. [PMID: 17502137 DOI: 10.1016/j.bmcl.2007.04.082] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Revised: 04/24/2007] [Accepted: 04/25/2007] [Indexed: 11/30/2022]
Abstract
We report on the design of benzodiazepinones as peptidomimetics at the carboxy terminus of hydroxyamides. Structure-activity relationships of diazepinones were investigated and orally active gamma-secretase inhibitors were synthesized. Active metabolites contributing to Abeta reduction were identified by analysis of plasma samples from Tg2576 mice. In particular, (S)-2-((S)-2-(3,5-difluorophenyl)-2-hydroxyacetamido)-N-((S,Z)-3-methyl-4-oxo-4,5-dihydro-3H-benzo[d][1,2]diazepin-5-yl)propanamide (BMS-433796) was identified with an acceptable pharmacodynamic and pharmacokinetic profile. Chronic dosing of BMS-433796 in Tg2576 mice suggested a narrow therapeutic window and Notch-mediated toxicity at higher doses.
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Affiliation(s)
- C V C Prasad
- Department of Discovery Chemistry, Bristol-Myers Squibb Pharmaceutical Research Institute, 5 Research Parkway, Wallingford, CT 06492, USA.
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13
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Liao YF, Wang BJ, Hsu WM, Lee H, Liao CY, Wu SY, Cheng HT, Hu MK. Unnatural amino acid-substituted (hydroxyethyl)urea peptidomimetics inhibit gamma-secretase and promote the neuronal differentiation of neuroblastoma cells. Mol Pharmacol 2006; 71:588-601. [PMID: 17105873 DOI: 10.1124/mol.106.024299] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Gamma-secretase, exhibiting characteristics of aspartyl protease, mediates the intramembranous proteolysis of beta-amyloid precursor protein (APP) and Notch, and it is considered to be a prime pharmacological target in the development of therapeutics for Alzheimer's disease (AD). To identify compounds that block gamma-secretase-mediated proteolysis, we used a highly sensitive cell-based reporter gene assay for gamma-secretase in which Gal4/VP16-tagged C99-APP was expressed as the immediate substrate of gamma-secretase, and Gal4/VP16-tagged APP intracellular domain released by the gamma-secretase cleavage then activated the expression of the Gal4-driven luciferase reporter gene. Using this reporter assay, we demonstrated that the newly synthesized (hydroxyethyl)urea peptidomimetics, which contain unnatural amino acid moieties at positions P1' and/or P3', can effectively inhibit gamma-secretase activity and significantly reduce Abeta production. The gamma-secretase-dependent S3 cleavage of Notch was also consistently blocked by these (hydroxyethyl)ureas as evidenced by the decreased generation of the Notch intracellular domain, a prerequisite for the activation of Notch signaling. The inhibition of Notch signaling by active Jia compounds efficiently promotes the neuronal differentiation of neuroblastoma cells, intervening in tumorigenesis and the malignancy of neuroblastomas. Our results suggest that (hydroxyethyl)urea peptidomimetics containing unnatural amino acid substitutions could represent a novel class of gamma-secretase inhibitors with enhanced stability, providing the basis for the further development of effective therapeutics for AD and neuroblastomas.
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Affiliation(s)
- Yung-Feng Liao
- Laboratory of Molecular Neurobiology, Institute of Cellular and Organismic Biology, Rm 238, Academia Sinica, 128 Academia Rd. Sec. 2, Taipei 115, Taiwan.
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14
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Li B, Andresen B, Brown MF, Buzon RA, Chiu CKF, Couturier M, Dias E, Urban FJ, Jasys VJ, Kath JC, Kissel W, Le T, Li ZJ, Negri J, Poss CS, Tucker J, Whritenour D, Zandi K. Process Development of CP-481715, a Novel CCR1 Antagonist. Org Process Res Dev 2005. [DOI: 10.1021/op050059w] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bryan Li
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Brian Andresen
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Matthew F. Brown
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Richard A. Buzon
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Charles K.-F. Chiu
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Michel Couturier
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Eric Dias
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Frank J. Urban
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - V. John Jasys
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - John C. Kath
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - William Kissel
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Tung Le
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Z. Jane Li
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Joanna Negri
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Christopher S. Poss
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - John Tucker
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - David Whritenour
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
| | - Kathleen Zandi
- Pfizer Global Research and Development, Groton Laboratories, Connecticut 06340, U.S.A
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Esler WP, Das C, Wolfe MS. Probing pockets S2-S4' of the gamma-secretase active site with (hydroxyethyl)urea peptidomimetics. Bioorg Med Chem Lett 2004; 14:1935-8. [PMID: 15050631 DOI: 10.1016/j.bmcl.2004.01.077] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2003] [Accepted: 01/26/2004] [Indexed: 10/26/2022]
Abstract
(Hydroxyethyl)urea peptidomimetics are potent inhibitors of gamma-secretase that are accessible in a few synthetic steps. Systematic alteration of P2-P4' revealed that the corresponding S2-S4' active site pockets accommodate a variety of substituents, consistent with the fact that this protease cleaves a variety of single-pass membrane proteins; however, phenylalanine is not well tolerated at P2'. A compound spanning P2-P3' was identified as a low nM inhibitor of gamma-secretase activity both in cells and under cell-free conditions.
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Affiliation(s)
- William P Esler
- Center for Neurologic Diseases, Harvard Medical School and Brigham and Womens Hospital, Boston, MA 02115, USA
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16
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Li B, Buzon RA, Chiu CKF, Colgan ST, Jorgensen ML, Kasthurikrishnan N. Stereoselective synthesis of 5-[(1S)-N-Boc-amino-(2S)-(3-fluorophenyl)ethyl]-dihydrofuran-2-one. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.07.097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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17
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Prasad CVC, Wallace OB, Noonan JW, Sloan CP, Lau W, Vig S, Parker MF, Smith DW, Hansel SB, Polson CT, Barten DM, Felsenstein KM, Roberts SB. Hydroxytriamides as potent γ-secretase inhibitors. Bioorg Med Chem Lett 2004; 14:1917-21. [PMID: 15050627 DOI: 10.1016/j.bmcl.2004.01.086] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Revised: 01/26/2004] [Accepted: 01/28/2004] [Indexed: 01/08/2023]
Abstract
Using a cell-based assay, we have identified optimal residues and key recognition elements necessary for inhibition of gamma-secretase. An (S)-hydroxy group or 3,5-difluorophenylacetyl group at the amino terminus and N-methyltertiary amide moiety at the carboxy terminus provided potent gamma-secretase inhibitors with an IC(50) <10 nM.
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Affiliation(s)
- C V C Prasad
- Department of Discovery Chemistry, Bristol-Myers Squibb Pharmaceutical Research Institute, 5 Research Parkway, Wallingford, CT 06492, USA.
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18
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Lewis HD, Pérez Revuelta BI, Nadin A, Neduvelil JG, Harrison T, Pollack SJ, Shearman MS. Catalytic site-directed gamma-secretase complex inhibitors do not discriminate pharmacologically between Notch S3 and beta-APP cleavages. Biochemistry 2003; 42:7580-6. [PMID: 12809514 DOI: 10.1021/bi034310g] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The generation of gamma-secretase inhibitors which block the release of beta-amyloid peptide (Abeta) has long been an attractive therapeutic avenue for treatment or prevention of Alzheimer's disease (AD). Such inhibitors would reduce levels of Abeta available for aggregation into toxic assemblies that lead to the plaque pathology found in affected brain tissue. Cumulative evidence suggests that the S3 cleavage of Notch is also dependent on presenilins (PS) and is carried out by the multimeric PS-containing gamma-secretase complex. It is therefore possible that Notch function could be affected by gamma-secretase inhibitors. To assess the relationship between the cleavage of these substrates in the same system, Western blot cleavage assays have been established using a human cell line stably expressing both the beta-amyloid precursor protein (beta-APP) and the truncated Notch1 receptor fragment NotchDeltaE. Thus, a direct correlation may be made, following inhibitor treatment, of the decrease in the levels of the cleavage products, Abeta peptide and the Notch intracellular domain (NICD), as well as the increase in stabilized levels of both substrates. This analysis has been performed with a range of selected gamma-secretase inhibitors from six distinct structural classes. Changes in all four species usually occur in concert and with remarkably good agreement. A significant cleavage window is not clearly apparent in any case. Thus, these Notch and beta-APP cleavages cannot be dissected apart easily since they show the same pharmacological profile of inhibition. Whether this translates into proportionally reduced Notch signaling in vivo, however, remains to be seen.
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Affiliation(s)
- Huw D Lewis
- Department of Biochemistry and Molecular Biology, The Neuroscience Research Centre, Merck Sharp & Dohme Research Laboratories, Terlings Park, Harlow, Essex, UK
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