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Braun-Cornejo M, Ornago C, Sonawane V, Haupenthal J, Kany AM, Diamanti E, Jézéquel G, Reiling N, Blankenfeldt W, Maas P, Hirsch AKH. Target-Directed Dynamic Combinatorial Chemistry Affords Binders of Mycobacterium tuberculosis IspE. ACS OMEGA 2024; 9:38160-38168. [PMID: 39281890 PMCID: PMC11391541 DOI: 10.1021/acsomega.4c05537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2024] [Revised: 08/14/2024] [Accepted: 08/21/2024] [Indexed: 09/18/2024]
Abstract
In the search for new antitubercular compounds, we leveraged target-directed dynamic combinatorial chemistry (tdDCC) as an efficient hit-identification method. In tdDCC, the target selects its own binders from a dynamic library generated in situ, reducing the number of compounds that require synthesis and evaluation. We combined a total of 12 hydrazides and six aldehydes to generate 72 structurally diverse N-acylhydrazones. To amplify the best binders, we employed anti-infective target 4-diphosphocytidyl-2C-methyl-d-erythritol kinase (IspE) from Mycobacterium tuberculosis (Mtb). We successfully validated the use of tdDCC as hit-identification method for IspE and optimized the analysis of tdDCC hit determination. From the 72 possible N-acylhydrazones, we synthesized 12 of them, revealing several new starting points for the development of IspE inhibitors as antibacterial agents.
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Affiliation(s)
- Maria Braun-Cornejo
- Specs Compound Handling, B.V., Bleiswijkseweg 55, 2712 PB Zoetermeer, The Netherlands
- Saarland University, Department of Pharmacy, Campus Building E8.1, 66123 Saarbrücken, Germany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123 Saarbrücken, Germany
| | - Camilla Ornago
- Department Structure and Function of Proteins Helmholtz Centre for Infection Research Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Vidhisha Sonawane
- RG Microbial Interface Biology, Research Center Borstel Leibniz Lung Center, Parkallee 1-40, 23845 Borstel, Germany
| | - Jörg Haupenthal
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123 Saarbrücken, Germany
| | - Andreas M Kany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123 Saarbrücken, Germany
| | - Eleonora Diamanti
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123 Saarbrücken, Germany
| | - Gwenaëlle Jézéquel
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123 Saarbrücken, Germany
| | - Norbert Reiling
- RG Microbial Interface Biology, Research Center Borstel Leibniz Lung Center, Parkallee 1-40, 23845 Borstel, Germany
- German Center for Infection Research (DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany
| | - Wulf Blankenfeldt
- Department Structure and Function of Proteins Helmholtz Centre for Infection Research Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Peter Maas
- Specs Compound Handling, B.V., Bleiswijkseweg 55, 2712 PB Zoetermeer, The Netherlands
| | - Anna K H Hirsch
- Saarland University, Department of Pharmacy, Campus Building E8.1, 66123 Saarbrücken, Germany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS) - Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123 Saarbrücken, Germany
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Choi SR, Narayanasamy P. Investigating Novel IspE Inhibitors of the MEP Pathway in Mycobacterium. Microorganisms 2023; 12:18. [PMID: 38276186 PMCID: PMC10819746 DOI: 10.3390/microorganisms12010018] [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: 12/05/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/27/2024] Open
Abstract
In a recent effort to mitigate harm from human pathogens, many biosynthetic pathways have been extensively evaluated for their ability to inhibit pathogen growth and to determine drug targets. One of the important products/targets of such pathways is isopentenyl diphosphate. Isopentenyl diphosphate is the universal precursor of isoprenoids, which are essential for the normal functioning of microorganisms. In general, two biosynthetic pathways lead to the formation of isopentenyl diphosphate: (1) the mevalonate pathway in animals; and (2) the non-mevalonate or methylerythritol phosphate (MEP) in many bacteria, and some protozoa and plants. Because the MEP pathway is not found in mammalian cells, it is considered an attractive target for the development of antimicrobials against a variety of human pathogens, including Mycobacterium tuberculosis (M.tb). In the MEP pathway, 4-diphosphocytidyl-2-c-methyl-d-erythritol kinase (IspE) phosphorylates 4-diphosphocytidyl-2-C-methyl-D-erythritol (CDPME) to form 4-diphosphocytidyl-2-C-methyl-D-erythritol 2-phosphate (CDPME2P). A virtual high-throughput screening against 15 million compounds was carried out by docking IspE protein. We identified an active heterotricyclic compound which showed enzymatic activity; namely, IC50 of 6 µg/mL against M.tb IspE and a MIC of 12 µg/mL against M.tb (H37Rv). Hence, we designed and synthesized similar new heterotricyclic compounds and tested them against mycobacterium, observing a MIC of 5 µg/mL against M. avium. This study will provide the critical insight necessary for developing novel antimicrobials that target the MEP pathways in pathogens.
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Affiliation(s)
| | - Prabagaran Narayanasamy
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
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Ropponen HK, Diamanti E, Johannsen S, Illarionov B, Hamid R, Jaki M, Sass P, Fischer M, Haupenthal J, Hirsch AKH. Exploring the Translational Gap of a Novel Class of Escherichia coli IspE Inhibitors. ChemMedChem 2023; 18:e202300346. [PMID: 37718320 DOI: 10.1002/cmdc.202300346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 09/15/2023] [Accepted: 09/15/2023] [Indexed: 09/19/2023]
Abstract
Discovery of novel antibiotics needs multidisciplinary approaches to gain target enzyme and bacterial activities while aiming for selectivity over mammalian cells. Here, we report a multiparameter optimisation of a fragment-like hit that was identified through a structure-based virtual-screening campaign on Escherichia coli IspE crystal structure. Subsequent medicinal-chemistry design resulted in a novel class of E. coli IspE inhibitors, exhibiting activity also against the more pathogenic bacteria Pseudomonas aeruginosa and Acinetobacter baumannii. While cytotoxicity remains a challenge for the series, it provides new insights on the molecular properties for balancing enzymatic target and bacterial activities simultaneously as well as new starting points for the development of IspE inhibitors with a predicted new mode of action.
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Affiliation(s)
- Henni-Karoliina Ropponen
- Drug Discovery and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123, Saarbrücken, Germany
- Saarland University, Department of Pharmacy, Campus Building E8.1, 66123, Saarbrücken, Germany
- Current address: AMR Action Fund GP GmbH, Messeplatz 10, 4058, Basel, Switzerland
| | - Eleonora Diamanti
- Drug Discovery and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123, Saarbrücken, Germany
| | - Sandra Johannsen
- Drug Discovery and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123, Saarbrücken, Germany
- Saarland University, Department of Pharmacy, Campus Building E8.1, 66123, Saarbrücken, Germany
| | - Boris Illarionov
- Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, 20146, Hamburg, Germany
| | - Rawia Hamid
- Drug Discovery and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123, Saarbrücken, Germany
- Saarland University, Department of Pharmacy, Campus Building E8.1, 66123, Saarbrücken, Germany
| | - Miriam Jaki
- Drug Discovery and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123, Saarbrücken, Germany
- Saarland University, Department of Pharmacy, Campus Building E8.1, 66123, Saarbrücken, Germany
- Current address: University of Freiburg, Institute of Pharmaceutical Sciences, Department of Pharmaceutics, Sonnenstraße 5, 79104, Freiburg, Germany
| | - Peter Sass
- Interfaculty Institute of Microbiology and Infection Medicine, Universität Tubingen
| | - Markus Fischer
- Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, 20146, Hamburg, Germany
| | - Jörg Haupenthal
- Drug Discovery and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123, Saarbrücken, Germany
| | - Anna K H Hirsch
- Drug Discovery and Optimization, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), Campus Building E8.1, 66123, Saarbrücken, Germany
- Saarland University, Department of Pharmacy, Campus Building E8.1, 66123, Saarbrücken, Germany
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The Multifaceted MEP Pathway: Towards New Therapeutic Perspectives. Molecules 2023; 28:molecules28031403. [PMID: 36771066 PMCID: PMC9919496 DOI: 10.3390/molecules28031403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 01/27/2023] [Accepted: 01/28/2023] [Indexed: 02/05/2023] Open
Abstract
Isoprenoids, a diverse class of natural products, are present in all living organisms. Their two universal building blocks are synthesized via two independent pathways: the mevalonate pathway and the 2-C-methyl-ᴅ-erythritol 4-phosphate (MEP) pathway. The presence of the latter in pathogenic bacteria and its absence in humans make all its enzymes suitable targets for the development of novel antibacterial drugs. (E)-4-Hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP), the last intermediate of this pathway, is a natural ligand for the human Vγ9Vδ2 T cells and the most potent natural phosphoantigen known to date. Moreover, 5-hydroxypentane-2,3-dione, a metabolite produced by Escherichia coli 1-deoxy-ᴅ-xylulose 5-phosphate synthase (DXS), the first enzyme of the MEP pathway, structurally resembles (S)-4,5-dihydroxy-2,3-pentanedione, a signal molecule implied in bacterial cell communication. In this review, we shed light on the diversity of potential uses of the MEP pathway in antibacterial therapies, starting with an overview of the antibacterials developed for each of its enzymes. Then, we provide insight into HMBPP, its synthetic analogs, and their prodrugs. Finally, we discuss the potential contribution of the MEP pathway to quorum sensing mechanisms. The MEP pathway, providing simultaneously antibacterial drug targets and potent immunostimulants, coupled with its potential role in bacterial cell-cell communication, opens new therapeutic perspectives.
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Saggu GS, Pala ZR, Garg S, Saxena V. New Insight into Isoprenoids Biosynthesis Process and Future Prospects for Drug Designing in Plasmodium. Front Microbiol 2016; 7:1421. [PMID: 27679614 PMCID: PMC5020098 DOI: 10.3389/fmicb.2016.01421] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 08/26/2016] [Indexed: 12/20/2022] Open
Abstract
The MEP (Methyl Erythritol Phosphate) isoprenoids biosynthesis pathway is an attractive drug target to combat malaria, due to its uniqueness and indispensability for the parasite. It is functional in the apicoplast of Plasmodium and its products get transported to the cytoplasm, where they participate in glycoprotein synthesis, electron transport chain, tRNA modification and several other biological processes. Several compounds have been tested against the enzymes involved in this pathway and amongst them Fosmidomycin, targeted against IspC (DXP reductoisomerase) enzyme and MMV008138 targeted against IspD enzyme have shown good anti-malarial activity in parasite cultures. Fosmidomycin is now-a-days prescribed clinically, however, less absorption, shorter half-life, and toxicity at higher doses, limits its use as an anti-malarial. The potential of other enzymes of the pathway as candidate drug targets has also been determined. This review details the various drug molecules tested against these targets with special emphasis to Plasmodium. We corroborate that MEP pathway functional within the apicoplast of Plasmodium is a major drug target, especially during erythrocytic stages. However, the major bottlenecks, bioavailability and toxicity of the new molecules needs to be addressed, before considering any new molecule as a potent antimalarial.
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Affiliation(s)
- Gagandeep S Saggu
- Molecular Parasitology and Systems Biology Laboratory, Department of Biological Sciences, Birla Institute of Technology and Science Pilani, India
| | - Zarna R Pala
- Molecular Parasitology and Systems Biology Laboratory, Department of Biological Sciences, Birla Institute of Technology and Science Pilani, India
| | - Shilpi Garg
- Molecular Parasitology and Systems Biology Laboratory, Department of Biological Sciences, Birla Institute of Technology and Science Pilani, India
| | - Vishal Saxena
- Molecular Parasitology and Systems Biology Laboratory, Department of Biological Sciences, Birla Institute of Technology and Science Pilani, India
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Harder M, Schäfer E, Kümin T, Illarionov B, Bacher A, Fischer M, Diederich F, Bernet B. 8-Substituted, syn-Configured Adenosine Derivatives as Potential Inhibitors of the Enzyme IspE from the Non-Mevalonate Pathway of Isoprenoid Biosynthesis. European J Org Chem 2015. [DOI: 10.1002/ejoc.201501150] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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7
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Bilbao N, Vázquez-González V, Aranda MT, González-Rodríguez D. Synthesis of 5-/8-Halogenated or Ethynylated Lipophilic Nucleobases as Potential Synthetic Intermediates for Supramolecular Chemistry. European J Org Chem 2015. [DOI: 10.1002/ejoc.201501026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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8
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Berryman OB, Johnson CA, Vonnegut CL, Fajardo KA, Zakharov LN, Johnson DW, Haley MM. Solid-State Examination of Conformationally Diverse Sulfonamide Receptors Based on Bis(2-anilinoethynyl)pyridine, -Bipyridine, and -Thiophene. CRYSTAL GROWTH & DESIGN 2015; 15:1502-1511. [PMID: 26405435 PMCID: PMC4577069 DOI: 10.1021/cg5018856] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Utilizing an induced-fit model and taking advantage of rotatable acetylenic C(sp)-C(sp2) bonds, we disclose the synthesis and solid-state structures of a series of conformationally diverse bis-sulfonamide arylethynyl receptors using either pyridine, 2,2'-bipyridine, or thiophene as the core aryl group. Whereas the bipyridine and thiophene structures do not appear to bind guests in the solid state, the pyridine receptors form 2 + 2 dimers with water molecules, two halides, or one of each, depending on the protonation state of the pyridine nitrogen atom. Isolation of a related bis-sulfonimide derivative demonstrates the importance of the sulfonamide N-H hydrogen bonds in dimer formation. The pyridine receptors form monomeric structures with larger guests such as BF4- or HSO4-, where the sulfonamide arms rotate to the side opposite the pyridine N atom.
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Affiliation(s)
- Orion B. Berryman
- Department of Chemistry & Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, United States
| | - Charles A. Johnson
- Department of Chemistry & Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, United States
| | - Chris L. Vonnegut
- Department of Chemistry & Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, United States
| | - Kevin A. Fajardo
- Department of Chemistry & Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, United States
| | - Lev N. Zakharov
- CAMCOR, University of Oregon, 1443 East 13th Avenue, Eugene, Oregon 97403, United States
| | - Darren W. Johnson
- Department of Chemistry & Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, United States
- Corresponding Authors: (D.W.J.) . (M.M.H.)
| | - Michael M. Haley
- Department of Chemistry & Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, United States
- Corresponding Authors: (D.W.J.) . (M.M.H.)
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9
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Persch E, Dumele O, Diederich F. Molekulare Erkennung in chemischen und biologischen Systemen. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201408487] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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10
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Persch E, Dumele O, Diederich F. Molecular recognition in chemical and biological systems. Angew Chem Int Ed Engl 2015; 54:3290-327. [PMID: 25630692 DOI: 10.1002/anie.201408487] [Citation(s) in RCA: 424] [Impact Index Per Article: 47.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Indexed: 12/13/2022]
Abstract
Structure-based ligand design in medicinal chemistry and crop protection relies on the identification and quantification of weak noncovalent interactions and understanding the role of water. Small-molecule and protein structural database searches are important tools to retrieve existing knowledge. Thermodynamic profiling, combined with X-ray structural and computational studies, is the key to elucidate the energetics of the replacement of water by ligands. Biological receptor sites vary greatly in shape, conformational dynamics, and polarity, and require different ligand-design strategies, as shown for various case studies. Interactions between dipoles have become a central theme of molecular recognition. Orthogonal interactions, halogen bonding, and amide⋅⋅⋅π stacking provide new tools for innovative lead optimization. The combination of synthetic models and biological complexation studies is required to gather reliable information on weak noncovalent interactions and the role of water.
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Affiliation(s)
- Elke Persch
- Laboratorium für Organische Chemie, Departement Chemie und Angewandte Biowissenschaften, ETH Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich (Switzerland)
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11
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Masini T, Hirsch AKH. Development of Inhibitors of the 2C-Methyl-d-erythritol 4-Phosphate (MEP) Pathway Enzymes as Potential Anti-Infective Agents. J Med Chem 2014; 57:9740-63. [DOI: 10.1021/jm5010978] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Tiziana Masini
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh
7, NL-9747
AG Groningen, The Netherlands
| | - Anna K. H. Hirsch
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh
7, NL-9747
AG Groningen, The Netherlands
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Mondal M, Radeva N, Köster H, Park A, Potamitis C, Zervou M, Klebe G, Hirsch AKH. Strukturbasiertes Design von Hemmstoffen der Aspartylprotease Endothiapepsin mittels dynamischer kombinatorischer Chemie. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201309682] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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13
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Mondal M, Radeva N, Köster H, Park A, Potamitis C, Zervou M, Klebe G, Hirsch AKH. Structure-based design of inhibitors of the aspartic protease endothiapepsin by exploiting dynamic combinatorial chemistry. Angew Chem Int Ed Engl 2014; 53:3259-63. [PMID: 24532096 DOI: 10.1002/anie.201309682] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Indexed: 12/19/2022]
Abstract
Structure-based design (SBD) can be used for the design and/or optimization of new inhibitors for a biological target. Whereas de novo SBD is rarely used, most reports on SBD are dealing with the optimization of an initial hit. Dynamic combinatorial chemistry (DCC) has emerged as a powerful strategy to identify bioactive ligands given that it enables the target to direct the synthesis of its strongest binder. We have designed a library of potential inhibitors (acylhydrazones) generated from five aldehydes and five hydrazides and used DCC to identify the best binder(s). After addition of the aspartic protease endothiapepsin, we characterized the protein-bound library member(s) by saturation-transfer difference NMR spectroscopy. Cocrystallization experiments validated the predicted binding mode of the two most potent inhibitors, thus demonstrating that the combination of de novo SBD and DCC constitutes an efficient starting point for hit identification and optimization.
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Affiliation(s)
- Milon Mondal
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen (The Netherlands) http://www.rug.nl/research/bio-organic-chemistry/hirsch/
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14
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Mombelli P, Le Chapelain C, Munzinger N, Joliat E, Illarionov B, Schweizer WB, Hirsch AKH, Fischer M, Bacher A, Diederich F. Imidazole- and Benzimidazole-Based Inhibitors of the Kinase IspE: Targeting the Substrate-Binding Site and the Triphosphate-Binding Loop of the ATP Site. European J Org Chem 2013. [DOI: 10.1002/ejoc.201201467] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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15
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Schütz AP, Locher S, Bernet B, Illarionov B, Fischer M, Bacher A, Diederich F. 5-Substituted (1-Thiolan-2-yl)cytosines as Inhibitors ofA. aeolicusandE. coliIspE Kinases: Very Different Affinities to Similar Substrate-Binding Sites. European J Org Chem 2013. [DOI: 10.1002/ejoc.201201454] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Abstract
INTRODUCTION The relict plastid, or apicoplast, is a characteristic feature of Plasmodium spp. and reflects the unusual evolutionary origins of these parasites. The essential role this organelle plays in the life of the parasite, and its unusual, non-mammalian metabolism, make the apicoplast an excellent drug target. AREAS COVERED This review focuses on the biological role of the apicoplast in the erythrocytic life cycle and what that reveals about existing drug targets. We also discuss the future of the apicoplast in the development of anti-malarials, emphasizing those pathways with greatest potential as a source of novel drug targets and emphasizing the need to understand in vitro drug responses to optimize eventual use of these drugs to treat malaria. EXPERT OPINION More than a decade of research on the apicoplast has confirmed the promise of this organelle as a source of drug targets. It is now possible to rationally assess the value of existing drugs and new drug targets, and to understand the role these drugs can play in the arsenal of anti-malarial treatments.
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Affiliation(s)
- Christopher D Goodman
- University of Melbourne, School of Botany, Professor's Walk, Parkville, Vic, 3010, Australia.
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17
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Gao P, Yang Y, Xiao C, Liu Y, Gan M, Guan Y, Hao X, Meng J, Zhou S, Chen X, Cui J. Identification and validation of a novel lead compound targeting 4-diphosphocytidyl-2-C-methylerythritol synthetase (IspD) of mycobacteria. Eur J Pharmacol 2012; 694:45-52. [PMID: 22975264 DOI: 10.1016/j.ejphar.2012.08.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 08/21/2012] [Accepted: 08/27/2012] [Indexed: 01/17/2023]
Abstract
Tuberculosis is a serious threat to world-wide public health usually caused in humans by Mycobacterium tuberculosis (M. tuberculosis). It exclusively utilizes the methylerythritol phosphate (MEP) pathway for biosynthesis of isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP), the precursors of all isoprenoid compounds. The 4-diphosphocytidyl-2-C-methyl-D-erythritol synthase (IspD; EC 2.7.7.60) is the key enzyme of the MEP pathway. It is also of interest as a new chemotherapeutic target, as the enzyme is absent in mammals and ispD is an essential gene for growth. A high-throughput screening method was therefore developed to identify compounds that inhibit IspD. This process was applied to identify a lead compound, domiphen bromide (DMB), that may effectively inhibit IspD. The inhibitory action of DMB was confirmed by over-expressing or down-regulating IspD in Mycobacterium smegmatis (M. smegmatis), demonstrating that DMB inhibit M. smegmatis growth additionally through an IspD-independent pathway. This also led to higher levels of growth inhibition when combined with IspD knockdown. This novel IspD inhibitor was also reported to exhibit antimycobacterial activity in vitro, an effect that likely occurs as a result of perturbation of cell wall biosynthesis.
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Affiliation(s)
- Peng Gao
- Department of Microbiology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
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18
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Schütz AP, Osawa S, Mathis J, Hirsch AKH, Bernet B, Illarionov B, Fischer M, Bacher A, Diederich F. Exploring the Ribose Sub-Pocket of the Substrate-Binding Site in Escherichia coli IspE: Structure-Based Design, Synthesis, and Biological Evaluation of Cytosines and Cytosine Analogues. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200296] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Tidten-Luksch N, Grimaldi R, Torrie LS, Frearson JA, Hunter WN, Brenk R. IspE inhibitors identified by a combination of in silico and in vitro high-throughput screening. PLoS One 2012; 7:e35792. [PMID: 22563402 PMCID: PMC3340893 DOI: 10.1371/journal.pone.0035792] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 03/22/2012] [Indexed: 11/19/2022] Open
Abstract
CDP-ME kinase (IspE) contributes to the non-mevalonate or deoxy-xylulose phosphate (DOXP) pathway for isoprenoid precursor biosynthesis found in many species of bacteria and apicomplexan parasites. IspE has been shown to be essential by genetic methods and since it is absent from humans it constitutes a promising target for antimicrobial drug development. Using in silico screening directed against the substrate binding site and in vitro high-throughput screening directed against both, the substrate and co-factor binding sites, non-substrate-like IspE inhibitors have been discovered and structure-activity relationships were derived. The best inhibitors in each series have high ligand efficiencies and favourable physico-chemical properties rendering them promising starting points for drug discovery. Putative binding modes of the ligands were suggested which are consistent with established structure-activity relationships. The applied screening methods were complementary in discovering hit compounds, and a comparison of both approaches highlights their strengths and weaknesses. It is noteworthy that compounds identified by virtual screening methods provided the controls for the biochemical screens.
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Affiliation(s)
| | | | | | | | - William N. Hunter
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, United Kingdom
- * E-mail: (WNH); (RB)
| | - Ruth Brenk
- Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee, United Kingdom
- * E-mail: (WNH); (RB)
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Wu YL, Ferroni F, Pieraccini S, Schweizer WB, Frank BB, Spada GP, Diederich F. 1,2-Di(phenylethynyl)ethenes with axially chiral, 2,2′-bridged 1,1′-binaphthyl substituents: potent cholesteric liquid-crystal inducers. Org Biomol Chem 2012; 10:8016-26. [DOI: 10.1039/c2ob25983d] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Gräwert T, Groll M, Rohdich F, Bacher A, Eisenreich W. Biochemistry of the non-mevalonate isoprenoid pathway. Cell Mol Life Sci 2011; 68:3797-814. [PMID: 21744068 PMCID: PMC11114746 DOI: 10.1007/s00018-011-0753-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Revised: 05/26/2011] [Accepted: 06/14/2011] [Indexed: 02/08/2023]
Abstract
The non-mevalonate pathway of isoprenoid (terpenoid) biosynthesis is essential in many eubacteria including the major human pathogen, Mycobacterium tuberculosis, in apicomplexan protozoa including the Plasmodium spp. causing malaria, and in the plastids of plants. The metabolic route is absent in humans and is therefore qualified as a promising target for new anti-infective drugs and herbicides. Biochemical and structural knowledge about all enzymes involved in the pathway established the basis for discovery and development of inhibitors by high-throughput screening of compound libraries and/or structure-based rational design.
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Affiliation(s)
- Tobias Gräwert
- Department Chemie, Lehrstuhl für Biochemie, Center for Integrated Protein Science München, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | - Michael Groll
- Department Chemie, Lehrstuhl für Biochemie, Center for Integrated Protein Science München, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | | | - Adelbert Bacher
- Department Chemie, Lehrstuhl für Biochemie, Center for Integrated Protein Science München, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | - Wolfgang Eisenreich
- Department Chemie, Lehrstuhl für Biochemie, Center for Integrated Protein Science München, Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
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22
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Tang M, Odejinmi SI, Allette YM, Vankayalapati H, Lai K. Identification of novel small molecule inhibitors of 4-diphosphocytidyl-2-C-methyl-D-erythritol (CDP-ME) kinase of Gram-negative bacteria. Bioorg Med Chem 2011; 19:5886-95. [PMID: 21903402 DOI: 10.1016/j.bmc.2011.08.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 08/02/2011] [Accepted: 08/08/2011] [Indexed: 11/17/2022]
Abstract
The biosyntheses of isoprenoids is essential for the survival in all living organisms, and requires one of the two biochemical pathways: (a) Mevalonate (MVA) Pathway or (b) Methylerythritol Phosphate (MEP) Pathway. The latter pathway, which is used by all Gram-negative bacteria, some Gram-positive bacteria and a few apicomplexan protozoa, provides an attractive target for the development of new antimicrobials because of its absence in humans. In this report, we describe two different approaches that we used to identify novel small molecule inhibitors of Escherichia coli and Yersinia pestis 4-diphosphocytidyl-2-C-methyl D-erythritol (CDP-ME) kinases, key enzymes of the MEP pathway encoded by the E. coli ispE and Y. pestisipk genes, respectively. In the first approach, we explored existing inhibitors of the GHMP kinases while in the second approach; we performed computational high-throughput screening of compound libraries by targeting the CDP-ME binding site of the two bacterial enzymes. From the first approach, we identified two compounds with 6-(benzylthio)-2-(2-hydroxyphenyl)-4-oxo-3,4-dihydro-2H-1,3-thiazine-5-carbonitrile and (Z)-3-methyl-4-((5-phenylfuran-2-yl)methylene)isoxazol-5(4H)-one scaffolds which inhibited E. coli CDP-ME kinase in vitro. We then performed substructure search and docking experiments based on these two scaffolds and identified twenty three analogs for structure-activity relationship (SAR) studies. Three new compounds from the isoxazol-5(4H)-one series have shown inhibitory activities against E. coli and Y. pestis CDP-ME kinases with the IC(50) values ranging from 7 to 13 μM. The second approach by computational high-throughput screening (HTS) of two million drug-like compounds yielded two compounds with benzenesulfonamide and acetamide moieties which, at a concentration of 20 μM, inhibited 80% and 65%, respectively, of control CDP-ME kinase activity.
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Affiliation(s)
- M Tang
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, 50 N. Mario Capecchi Drive, SOM Room 2C412, Salt Lake City, UT 84132, USA
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23
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Börner HG. Precision Polymers-Modern Tools to Understand and Program Macromolecular Interactions. Macromol Rapid Commun 2010; 32:115-26. [DOI: 10.1002/marc.201000646] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 11/17/2010] [Indexed: 11/11/2022]
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24
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Obiol-Pardo C, Cordero A, Rubio-Martinez J, Imperial S. Homology modeling of Mycobacterium tuberculosis 2C-methyl-D-erythritol-4-phosphate cytidylyltransferase, the third enzyme in the MEP pathway for isoprenoid biosynthesis. J Mol Model 2009; 16:1061-73. [PMID: 19916033 DOI: 10.1007/s00894-009-0615-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Accepted: 10/06/2009] [Indexed: 02/02/2023]
Abstract
Tuberculosis is one of the leading infectious diseases in humans. Discovering new treatments for this disease is urgently required, especially in view of the emergence of multiple drug resistant organisms and to reduce the total duration of current treatments. The synthesis of isoprenoids in Mycobacterium tuberculosis has been reported as an interesting pathway to target, and particular attention has been focused on the methylerythritol phosphate (MEP) pathway comprising the early steps of isoprenoid biosynthesis. In this context we have studied the enzyme 2C-methyl-D-erythritol-4-phosphate cytidylyltransferase (CMS), the third enzyme in the MEP pathway, since the lack of a resolved structure of this protein in M. tuberculosis has seriously limited its use as a drug target. We performed homology modeling of M. tuberculosis CMS in order to provide a reliable model for use in structure-based drug design. After evaluating the quality of the model, we performed a thorough study of the catalytic site and the dimerization interface of the model, which suggested the most important sites (conserved and non-conserved) that could be useful for drug discovery and mutagenesis studies. We found that the metal coordination of CDP-methylerythritol in M. tuberculosis CMS differs substantially with respect to the Escherichia coli variant, consistent with the fact that the former is able to utilize several metal ions for catalysis. Moreover, we propose that electrostatic interactions could explain the higher affinity of the MEP substrate compared with the cytosine 5'-triphosphate substrate in the M. tuberculosis enzyme as reported previously.
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Affiliation(s)
- Cristian Obiol-Pardo
- Dept. de Química Física, Universitat de Barcelona, Intitut de Recerca en Química Teòrica i Computacional (IQTCUB), Martí i Franquès 1, 08028, Barcelona, Spain
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25
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Zürcher M, Hof F, Barandun L, Schütz A, Schweizer WB, Meyer S, Bur D, Diederich F. Synthesis ofexo-3-Amino-7-azabicyclo[2.2.1]heptanes as a Class of Malarial Aspartic Protease Inhibitors: Exploration of Two Binding Pockets. European J Org Chem 2009. [DOI: 10.1002/ejoc.200801184] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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26
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Eoh H, Brennan PJ, Crick DC. The Mycobacterium tuberculosis MEP (2C-methyl-d-erythritol 4-phosphate) pathway as a new drug target. Tuberculosis (Edinb) 2008; 89:1-11. [PMID: 18793870 DOI: 10.1016/j.tube.2008.07.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 07/15/2008] [Accepted: 07/23/2008] [Indexed: 10/21/2022]
Abstract
Tuberculosis (TB) is still a major public health problem, compounded by the human immunodeficiency virus (HIV)-TB co-infection and recent emergence of multidrug-resistant (MDR) and extensively drug resistant (XDR)-TB. Novel anti-TB drugs are urgently required. In this context, the 2C-methyl-d-erythritol 4-phosphate (MEP) pathway of Mycobacterium tuberculosis has drawn attention; it is one of several pathways vital for M. tuberculosis viability and the human host lacks homologous enzymes. Thus, the MEP pathway promises bacterium-specific drug targets and the potential for identification of lead compounds unencumbered by target-based toxicity. Indeed, fosmidomycin is now known to inhibit the second step in the MEP pathway. This review describes the cardinal features of the main enzymes of the MEP pathway in M. tuberculosis and how these can be manipulated in high throughput screening campaigns in the search for new anti-infectives against TB.
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Affiliation(s)
- Hyungjin Eoh
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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27
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A fluorine scan of non-peptidic inhibitors of neprilysin: Fluorophobic and fluorophilic regions in an enzyme active site. J Fluor Chem 2008. [DOI: 10.1016/j.jfluchem.2008.02.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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28
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Zürcher M, Diederich F. Structure-Based Drug Design: Exploring the Proper Filling of Apolar Pockets at Enzyme Active Sites. J Org Chem 2008; 73:4345-61. [DOI: 10.1021/jo800527n] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Martina Zürcher
- Department of Chemistry and Applied Biosciences, Laboratorium für Organische Chemie, ETH Zürich, HCI G 313, 8093 Zürich, Switzerland
| | - François Diederich
- Department of Chemistry and Applied Biosciences, Laboratorium für Organische Chemie, ETH Zürich, HCI G 313, 8093 Zürich, Switzerland
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29
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Synthesis and Characterization of Cytidine Derivatives that Inhibit the Kinase IspE of the Non-Mevalonate Pathway for Isoprenoid Biosynthesis. ChemMedChem 2008; 3:91-101. [DOI: 10.1002/cmdc.200700208] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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30
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Berryman O, Johnson C, Zakharov L, Haley M, Johnson D. Water and Hydrogen Halides Serve the Same Structural Role in a Series of 2+2 Hydrogen-Bonded Dimers Based on 2,6-Bis(2-anilinoethynyl)pyridine Sulfonamide Receptors. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200703971] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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31
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Hirsch AKH, Alphey MS, Lauw S, Seet M, Barandun L, Eisenreich W, Rohdich F, Hunter WN, Bacher A, Diederich F. Inhibitors of the kinase IspE: structure–activity relationships and co-crystal structure analysis. Org Biomol Chem 2008; 6:2719-30. [DOI: 10.1039/b804375b] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Berryman OB, Johnson CA, Zakharov LN, Haley MM, Johnson DW. Water and Hydrogen Halides Serve the Same Structural Role in a Series of 2+2 Hydrogen-Bonded Dimers Based on 2,6-Bis(2-anilinoethynyl)pyridine Sulfonamide Receptors. Angew Chem Int Ed Engl 2008; 47:117-20. [PMID: 17992675 DOI: 10.1002/anie.200703971] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Orion B Berryman
- Department of Chemistry and Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, USA
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33
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Munos JW, Pu X, Liu HW. Synthesis and analysis of a fluorinated product analogue as an inhibitor for 1-deoxy-D-xylulose 5-phosphate reductoisomerase. Bioorg Med Chem Lett 2007; 18:3090-4. [PMID: 18078746 DOI: 10.1016/j.bmcl.2007.11.062] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Revised: 11/12/2007] [Accepted: 11/15/2007] [Indexed: 11/19/2022]
Abstract
1-deoxy-D-xylulose 5-phosphate (DXP) reductoisomerase (DXR) is an NADPH-dependent enzyme catalyzing the rearrangement and reduction of DXP to methyl-D-erythritol 4-phosphate (MEP). Two mechanisms for this enzymatic reaction have been proposed, involving either an alpha-ketol rearrangement or a retroaldol/aldol rearrangement. In this study, a fluorinated product analogue, FCH(2)-MEP, was synthesized as a possible mechanism-based inactivator for DXR if the retroaldol/aldol mechanism is operative. FCH(2)-MEP was found to be a weak competitive inhibitor, and thus was unable to discriminate between the mechanisms. This result is due to the inability of the targeted enzyme, DXR, to oxidize FCH(2)-MEP to the aldehyde intermediate that is common to both mechanisms. While FCH(2)-MEP failed to act as a mechanism-based inactivator, the insight gained from this study will assist in the future design of inhibitors of DXR.
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Affiliation(s)
- Jeffrey W Munos
- Division of Medicinal Chemistry, College of Pharmacy, and Department of Chemistry and Biochemistry, University of Texas, Austin, TX 78712, USA
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34
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Thondorf I, Rudzevich Y, Rudzevich V, Böhmer V. Reasons for the exclusive formation of heterodimeric capsules between tetra-tolyl and tetra-tosylurea calix[4]arenes. Org Biomol Chem 2007; 5:2775-82. [PMID: 17700845 DOI: 10.1039/b708679b] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The selective heterodimerization of tetra-tolyl () and tetra-tosylurea () calixarenes, serendipitously found by Rebek et al. (R. K. Castellano, B. H. Kim and J. Rebek, Jr., J. Am. Chem. Soc., 1997, 119, 12671-12672), has been used for the construction of highly sophisticated macrocycles and well-defined supramolecular assemblies. Regrettably, hitherto, neither the exact structure of these heterodimers nor the reason for their exclusive formation is known. We present molecular dynamics simulations using the AMBER force field in explicit chloroform solvent for the two homodimers, the heterodimer and the two uncomplexed tetra-urea calixarenes. The rigid rotation about the C-S-N-C bond of the tosylurea group has been calculated for a model compound (N-mesylformamide) at the RHF/6-31G* level of theory. The calculations suggest that the heterodimer . is energetically favored over the homodimers by a sterically relaxed conformation of the tosylurea hemisphere in ., by a moderate degree of reorganization of the hemispheres from the uncomplexed to the complexed state and by favorable interactions between the hemispheres. The tosylurea S=O groups are involved in the hydrogen bonding system which results in different sizes of the three capsules in increasing order . < . < .. To prove the computational predictions, 1H NMR experiments have been carried out with solvents/guests differing in shape and size. The largest capsule . prefers the larger guests toluene and p-xylene while the latter is not encapsulated in the smallest capsule ..
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Affiliation(s)
- Iris Thondorf
- Institut für Biochemie und Biotechnologie, Fakultät für Naturwissenschaften I Biowissenschaften, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 3, D-06099, Halle, Germany.
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