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Hoving M, Haaksma JJ, Stoppel A, Chronc L, Hoffmann J, Beil SB. Triplet Energy Transfer Mechanism in Copper Photocatalytic N- and O-Methylation. Chemistry 2024; 30:e202400560. [PMID: 38363220 DOI: 10.1002/chem.202400560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 02/15/2024] [Accepted: 02/16/2024] [Indexed: 02/17/2024]
Abstract
Methylation reactions are chemically simple but challenging to perform under mild and non-toxic conditions. A photochemical energy transfer strategy was merged with copper catalysis to enable fast reaction times of minutes and broad applicability to N-heterocycles, (hetero-)aromatic carboxylic acids, and drug-like molecules in high yields and good functional group tolerance. Detailed mechanistic investigations, using kinetic analysis, aprotic MS, UV/Vis, and luminescence quenching experiments revealed a triplet-triplet energy transfer mechanism between hypervalent iodine(III) reagents and readily available photosensitizers.
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Affiliation(s)
- Martijn Hoving
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Jacob-Jan Haaksma
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Anne Stoppel
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Lukas Chronc
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Jonas Hoffmann
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
| | - Sebastian B Beil
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG, Groningen, The Netherlands
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2
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Kiriwan D, Choowongkomon K. In silico structural elucidation of the rabies RNA-dependent RNA polymerase (RdRp) toward the identification of potential rabies virus inhibitors. J Mol Model 2021; 27:183. [PMID: 34031746 PMCID: PMC8143072 DOI: 10.1007/s00894-021-04798-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 05/17/2021] [Indexed: 11/25/2022]
Abstract
The rabies virus (RABV) is a non-segmented, negative single-stranded RNA virus which causes acute infection of the central nervous system in humans. Once symptoms appear, the result is nearly always death, and to date, post-exposure prophylaxis (PEP) is the only treatment applicable only immediately after an exposure. Previous studies have identified viral RNA-dependent RNA polymerase (RdRp) as a potential drug target due to its significant role in viral replication and transcription. Herein we generated an energy-minimized homology model of RABIES-RdRp and used it for virtual screening against 2045 NCI Diversity Set III library. The best five ligand-RdRp complexes were picked for further energy minimization via molecular dynamics (MDs) where the complex with ligand Z01690699 shows a minimum score characterized with stable hydrogen bonds and hydrophobic interactions with the catalytic site residues. Our study identified an important ligand for development of remedial approach for treatment of rabies infection.
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Affiliation(s)
- Duangnapa Kiriwan
- Interdisciplinary Program in Genetic Engineering, Graduate School, Kasetsart University, Chatuchak, Bangkok, Thailand
| | - Kiattawee Choowongkomon
- Department of Biochemistry, Faculty of Science, Kasetsart University, Bangkok, Thailand. .,Center for Advanced Studies in Nanotechnology for Chemical, Food and Agricultural Industries, KU Institute for Advanced Studies, Kasetsart University, Bangkok, Thailand.
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3
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Design, synthesis, and bioassay of 4-thiazolinone derivatives as influenza neuraminidase inhibitors. Eur J Med Chem 2021; 213:113161. [PMID: 33540229 DOI: 10.1016/j.ejmech.2021.113161] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 12/13/2020] [Accepted: 01/03/2021] [Indexed: 01/09/2023]
Abstract
A series of 4-thiazolinone derivatives (D1-D58) were designed and synthesized. All of the derivatives were evaluated in vitro for neuraminidase (NA) inhibitory activities against influenza virus A (H1N1), and the inhibitory activities of the five most potent compounds were further evaluated on NA from two different influenza viral subtypes (H3N2 and B), and then their in vitro anti-viral activities were evaluated using the cytopathic effect (CPE) reduction assay. The results showed that the majority of the target compounds exhibited moderate to good NA inhibitory activity. Compound D18 presented the most potent inhibitory activity with IC50 values of 13.06 μM against influenza H1N1 subtype. Among the selected compounds, D18 and D41 turned out to be the most potent inhibitors against influenza virus H3N2 subtype (IC50 = 15.00 μM and IC50 = 14.97 μM, respectively). D25 was the most potent compound against influenza B subtype (IC50 = 16.09 μM). In addition, D41 showed low toxicity and greater potency than reference compounds Oseltamivir and Amantadine against N1-H275Y variant in cellular assays. The structure-activity relationship (SAR) analysis showed that introducing 4-CO2H, 4-OH, 3-OCH3-4-OH substituted benzyl methylene can greatly improve the activity of 4-thiazolinones. Further SAR analysis indicated that 4-thiazolinone and ferulic acid fragments are necessary fragments of target compounds for inhibiting NA. Molecular docking was performed to study the interaction between compound D41 and the active site of NA. This study may providing important information for new drug development for anti-influenza virus including mutant influenza virus.
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Jennings JJ, Milic M, Targos K, Franz AK. NMR quantification of H-bond donating ability for bioactive functional groups and isosteres. Eur J Med Chem 2020; 207:112693. [PMID: 32862126 DOI: 10.1016/j.ejmech.2020.112693] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/15/2020] [Accepted: 07/24/2020] [Indexed: 12/20/2022]
Abstract
The H-bond donating ability for 127 compounds including drug fragments and isosteres have been quantified using a simple and rapid method with 31P NMR spectroscopy. Functional groups important to medicinal chemistry were evaluated including carboxylic acids, alcohols, phenols, thioic acids and nitrogen group H-bond donors. 31P NMR shifts for binding to a phosphine oxide probe have a higher correlation with equilibrium constants for H-bonding (log KHA) than acidity (pKa), indicating that these binding experiments are representative of H-bonding ability and not proton transfer. Additionally, 31P NMR binding data for carboxylic acid isosteres correlates with physicochemical properties such as lipophilicity, membrane permeability and plasma protein binding. This method has been used to evaluate the H-bond donating ability of small molecule drug compounds such as NSAIDs and antimicrobials.
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Affiliation(s)
- Julia J Jennings
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA, 95616, United States
| | - Mira Milic
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA, 95616, United States
| | - Karina Targos
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA, 95616, United States
| | - Annaliese K Franz
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA, 95616, United States.
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5
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Computational analysis of drug like candidates against Neuraminidase of Human Influenza A virus subtypes. INFORMATICS IN MEDICINE UNLOCKED 2020. [DOI: 10.1016/j.imu.2019.100284] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Rustmeier NH, Strebl M, Stehle T. The Symmetry of Viral Sialic Acid Binding Sites-Implications for Antiviral Strategies. Viruses 2019; 11:v11100947. [PMID: 31615155 PMCID: PMC6832341 DOI: 10.3390/v11100947] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/02/2019] [Accepted: 10/09/2019] [Indexed: 12/12/2022] Open
Abstract
Virus infections are initiated by the attachment of the viral particle to protein or carbohydrate receptors on the host cell. Sialic acid-bearing glycan structures are prominently displayed at the cell surface, and, consequently, these structures can function as receptors for a large number of diverse viruses. Structural biology research has helped to establish the molecular bases for many virus–sialic acid interactions. Due to the icosahedral 532 point group symmetry that underlies many viral capsids, the receptor binding sites are frequently arranged in a highly symmetric fashion and linked by five-fold, three-fold, or two-fold rotation axes. For the inhibition of viral attachment, one emerging strategy is based on developing multivalent sialic acid-based inhibitors that can simultaneously engage several of these binding sites, thus binding viral capsids with high avidity. In this review, we will evaluate the structures of non-enveloped virus capsid proteins bound to sialylated glycan receptors and discuss the potential of these structures for the development of potent antiviral attachment inhibitors.
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Affiliation(s)
- Nils H Rustmeier
- Interfaculty Institute of Biochemistry, University of Tuebingen, 72076 Tuebingen, Baden-Wuerttemberg, Germany.
| | - Michael Strebl
- Interfaculty Institute of Biochemistry, University of Tuebingen, 72076 Tuebingen, Baden-Wuerttemberg, Germany.
| | - Thilo Stehle
- Interfaculty Institute of Biochemistry, University of Tuebingen, 72076 Tuebingen, Baden-Wuerttemberg, Germany.
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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Sharma G, Vasanth Kumar S, Wahab HA. Molecular docking, synthesis, and biological evaluation of naphthoquinone as potential novel scaffold for H5N1 neuraminidase inhibition. J Biomol Struct Dyn 2017; 36:233-242. [DOI: 10.1080/07391102.2016.1274271] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Garima Sharma
- Department of Chemistry, Karunya University, Coimbatore, India
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia
| | | | - Habibah A. Wahab
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia
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Bat-derived influenza-like viruses H17N10 and H18N11. Trends Microbiol 2014; 22:183-91. [PMID: 24582528 PMCID: PMC7127364 DOI: 10.1016/j.tim.2014.01.010] [Citation(s) in RCA: 236] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 01/26/2014] [Accepted: 01/30/2014] [Indexed: 11/24/2022]
Abstract
Bat-derived influenza-like virus hemagglutinin and neuraminidase lack canonical functions and structures. Putative functional modules/domains in other bat-derived influenza-like proteins are conserved. Potential genomic reassortments with canonical influenza virus cannot be ruled out and should be assessed.
Shorebirds and waterfowls are believed to be the reservoir hosts for influenza viruses, whereas swine putatively act as mixing vessels. The recent identification of two influenza-like virus genomes (designated H17N10 and H18N11) from bats has challenged this notion. A crucial question concerns the role bats might play in influenza virus ecology. Structural and functional studies of the two major surface envelope proteins, hemagglutinin (HA) and neuraminidase (NA), demonstrate that neither has canonical HA or NA functions found in influenza viruses. However, putative functional modules and domains in other encoded proteins are conserved, and the N-terminal domain of the H17N10 polymerase subunit PA has a classical structure and function. Therefore, potential genomic reassortments of such influenza-like viruses with canonical influenza viruses cannot be excluded at this point and should be assessed.
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Identification of neuraminidase inhibitors by structure-based screening: promising new leads for influenza. Med Chem Res 2013. [DOI: 10.1007/s00044-013-0862-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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10
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Chamni S, De-Eknamkul W. Recent progress and challenges in the discovery of new neuraminidase inhibitors. Expert Opin Ther Pat 2013; 23:409-23. [DOI: 10.1517/13543776.2013.765861] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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11
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Li Y, Silamkoti A, Kolavi G, Mou L, Gulati S, Air GM, Brouillette WJ. Pyrrolidinobenzoic acid inhibitors of influenza virus neuraminidase: the hydrophobic side chain influences type A subtype selectivity. Bioorg Med Chem 2012; 20:4582-9. [PMID: 22677529 PMCID: PMC3401542 DOI: 10.1016/j.bmc.2012.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 04/28/2012] [Accepted: 05/02/2012] [Indexed: 10/28/2022]
Abstract
Neuraminidase (NA) plays a critical role in the life cycle of influenza virus and is a target for new therapeutic agents. A series of influenza neuraminidase inhibitors with the pyrrolidinobenzoic acid scaffold containing lipophilic side chains at the C3 position have been synthesized and evaluated for influenza neuraminidase inhibitory activity. The size and geometry of the C3 side chains have been modified in order to investigate structure-activity relationships. The results indicated that size and geometry of the C3-side chain are important for selectivity of inhibition against N1 versus N2 NA, important type A influenza variants that infect man, including the highly lethal avian influenza.
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Affiliation(s)
- Yanwu Li
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Venkatramani L, Johnson ES, Kolavi G, Air GM, Brouillette WJ, Mooers BHM. Crystal structure of a new benzoic acid inhibitor of influenza neuraminidase bound with a new tilt induced by overpacking subsite C6. BMC STRUCTURAL BIOLOGY 2012; 12:7. [PMID: 22559154 PMCID: PMC3416664 DOI: 10.1186/1472-6807-12-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 05/06/2012] [Indexed: 11/10/2022]
Abstract
Background Influenza neuraminidase (NA) is an important target for antiviral inhibitors since its active site is highly conserved such that inhibitors can be cross-reactive against multiple types and subtypes of influenza. Here, we discuss the crystal structure of neuraminidase subtype N9 complexed with a new benzoic acid based inhibitor (2) that was designed to add contacts by overpacking one side of the active site pocket. Inhibitor 2 uses benzoic acid to mimic the pyranose ring, a bis-(hydroxymethyl)-substituted 2-pyrrolidinone ring in place of the N-acetyl group of the sialic acid, and a branched aliphatic structure to fill the sialic acid C6 subsite. Results Inhibitor 2 {4-[2,2-bis(hydroxymethyl)-5-oxo-pyrrolidin-1-yl]-3-[(dipropylamino)methyl)]benzoic acid} was soaked into crystals of neuraminidase of A/tern/Australia/G70c/75 (N9), and the structure refined with 1.55 Å X-ray data. The benzene ring of the inhibitor tilted 8.9° compared to the previous compound (1), and the number of contacts, including hydrogen bonds, increased. However, the IC50 for compound 2 remained in the low micromolar range, likely because one propyl group was disordered. In this high-resolution structure of NA isolated from virus grown in chicken eggs, we found electron density for additional sugar units on the N-linked glycans compared to previous neuraminidase structures. In particular, seven mannoses and two N-acetylglucosamines are visible in the glycan attached to Asn200. This long, branched high-mannose glycan makes significant contacts with the neighboring subunit. Conclusions We designed inhibitor 2 with an extended substituent at C4-corresponding to C6 of sialic acid-to increase the contact surface in the C6-subsite and to force the benzene ring to tilt to maximize these interactions while retaining the interactions of the carboxylate and the pyrolidinone substituents. The crystal structure at 1.55 Å showed that we partially succeeded in that the ring in 2 is tilted relative to 1 and the number of contacts increased, but one hydrophobic branch makes no contacts, perhaps explaining why the IC50 did not decrease. Future design efforts will include branches of unequal length so that both branches may be accommodated in the C6-subsite without conformational disorder. The high-mannose glycan attached to Asn200 makes several inter-subunit contacts and appears to stabilize the tetramer.
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Affiliation(s)
- Lalitha Venkatramani
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, 941 Stanton L, Young Blvd, Oklahoma City, OK 73104, USA
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Zhang J, Shan Y, Pan X, Wang C, Xu W, He L. Molecular docking, 3D-QSAR studies, and in silico ADME prediction of p-aminosalicylic acid derivatives as neuraminidase inhibitors. Chem Biol Drug Des 2011; 78:709-17. [PMID: 21752201 DOI: 10.1111/j.1747-0285.2011.01179.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Neuraminidase (NA) is a major glycoprotein of influenza virus which is essential for viral infection. It offers a potential target for antiviral drug design and discovery. To develop novel potent neuraminidase inhibitors (NAI), Surflex-Dock was employed to dock 40 hydrophobic p-aminosalicylic acid derivatives into the active site of NA. The 3D-quantitative structure-activity relationship studies involving comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were carried out on 40 molecules. Both CoMFA (q(2) = 0.628, r(2) = 0.697) and CoMSIA (q(2) = 0.746, r(2) = 0.816) gave reasonable results. A preliminary pharmacokinetic profile of these NAI was also performed on the basis of Volsurf predictions. The results obtained from this study will be useful in the design of novel potent NAI.
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Affiliation(s)
- Jie Zhang
- College of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province 710061, China.
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14
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Skrzypek S. Electrochemical Studies of the Neuraminidase Inhibitor Zanamivir and its Voltammetric Determination in Spiked Urine. ELECTROANAL 2010. [DOI: 10.1002/elan.201000163] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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15
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Sun J, Cai S, Yan N, Mei H. Docking and 3D-QSAR studies of influenza neuraminidase inhibitors using three-dimensional holographic vector of atomic interaction field analysis. Eur J Med Chem 2010; 45:1008-14. [PMID: 19969399 DOI: 10.1016/j.ejmech.2009.11.043] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2009] [Revised: 11/12/2009] [Accepted: 11/20/2009] [Indexed: 11/19/2022]
Affiliation(s)
- Jiaying Sun
- College of Bioengineering, Chongqing University, Chongqing 400044, China.
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Mihajlovic ML, Mitrasinovic PM. Applications of the ArgusLab4/AScore protocol in the structure-based binding affinity prediction of various inhibitors of group-1 and group-2 influenza virus neuraminidases (NAs). MOLECULAR SIMULATION 2009. [DOI: 10.1080/08927020802430752] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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17
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Li ZS, Sun JY, Liang GZ, Lu FL, Zhu WP, Zhang MJ, Zhang Y, Yang SB, Shu M, Chen GH, Lu TT. On Three-Dimensional Holographic Vector of Atomic Interaction Field Analysis for Influenza Neuraminidase Inhibitors. Chem Biol Drug Des 2009; 73:236-43. [DOI: 10.1111/j.1747-0285.2008.00767.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abu Hammad AM, Afifi FU, Taha MO. Combining docking, scoring and molecular field analyses to probe influenza neuraminidase-ligand interactions. J Mol Graph Model 2007; 26:443-56. [PMID: 17360207 DOI: 10.1016/j.jmgm.2007.02.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 02/05/2007] [Accepted: 02/06/2007] [Indexed: 11/15/2022]
Abstract
In this project, several docking conditions, scoring functions and corresponding protein-aligned molecular field analysis (CoMFA) models were evaluated for a diverse set of neuraminidase (NA) inhibitors. To this end, a group of inhibitors were docked into the active site of NA. The docked structures were utilized to construct a corresponding protein-aligned CoMFA models by employing probe-based (H+, OH, CH3) energy grids and genetic partial least squares (G/PLS) statistical analysis. A total of 16 different docking configurations were evaluated, of which some succeeded in producing self-consistent and predictive CoMFA models. However, the best model coincided with docking the ionized ligands into the hydrated form of the binding site via PLP1 scoring function (r2LOO=0.735, r2PRESS against 24 test compounds=0.828). The highest-ranking CoMFA models were employed to probe NA-ligand interactions. Further validation by comparison with a co-crystallized ligand-NA crystallographic structure was performed. This combination of docking/scoring/CoMFA modeling provided interesting insights into the binding of different NA inhibitors.
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Affiliation(s)
- Areej M Abu Hammad
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, University of Jordan, Queen Rania Street, Amman 11942, Jordan
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Islam T, von Itzstein M. Anti-Influenza Drug Discovery: Are We Ready for the Next Pandemic? Adv Carbohydr Chem Biochem 2007; 61:293-352. [DOI: 10.1016/s0065-2318(07)61006-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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20
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Neres J, Bonnet P, Edwards PN, Kotian PL, Buschiazzo A, Alzari PM, Bryce RA, Douglas KT. Benzoic acid and pyridine derivatives as inhibitors of Trypanosoma cruzi trans-sialidase. Bioorg Med Chem 2006; 15:2106-19. [PMID: 17218104 DOI: 10.1016/j.bmc.2006.12.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Revised: 12/07/2006] [Accepted: 12/13/2006] [Indexed: 12/13/2022]
Abstract
Benzoic acid and pyridine derivatives inhibit recombinant trans-sialidase from Trypanosoma cruzi with I50 values between 0.4 and 1mM. The best compounds, 4-acetylamino-3-hydroxymethylbenzoic acid and 5-acetylamino-6-aminopyridine-2-carboxylic acid, provide new leads to inhibitors not containing the synthetically complex sialic acid structure. The weak inhibition by such compounds contrasts with their much stronger inhibition of neuraminidase from Influenza virus.
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Affiliation(s)
- João Neres
- School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Manchester, M13 9PL, UK
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21
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Influenza Neuraminidase Inhibitors as Antiviral Agents. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 2006. [DOI: 10.1016/s0065-7743(06)41019-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Bethell RC, Smith PW. Sialidase as a target for inhibitors of influenza virus replication. Expert Opin Investig Drugs 2005; 6:1501-9. [PMID: 15989515 DOI: 10.1517/13543784.6.10.1501] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Structure-based drug design has led to the identification of potent and selective inhibitors of influenza virus sialidase, which have antiviral activity in vitro and in experimental animal models of influenza infection. Clinical studies with one such sialidase inhibitor, zanamivir, have shown this compound to be a safe and effective therapy for influenza infections in man. Passage of influenza viruses in the presence of zanamivir in vitro has been shown to result in the selection of viruses with reduced sensitivity to this drug. To date, however, there have been no reports of the isolation of zanamivir-resistant viruses during clinical studies of this compound. Further application of structure-based drug design is yielding novel classes of potent inhibitors of influenza virus sialidase.
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Affiliation(s)
- R C Bethell
- Enzyme Pharmacology Unit, Glaxo Wellcome Research and Development, Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK
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Brouillette WJ, Bajpai SN, Ali SM, Velu SE, Atigadda VR, Lommer BS, Finley JB, Luo M, Air GM. Pyrrolidinobenzoic acid inhibitors of influenza virus neuraminidase: modifications of essential pyrrolidinone ring substituents. Bioorg Med Chem 2003; 11:2739-49. [PMID: 12788348 DOI: 10.1016/s0968-0896(03)00271-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We recently reported the first benzoic acid, 1-[4-carboxy-2-(3-pentylamino)phenyl]-5,5-bis(hydroxymethyl)pyrrolidin-2-one (8), that is a potent inhibitor of avian influenza A neuraminidase (N9) and, unlike other reported potent neuraminidase inhibitors, does not contain a basic aliphatic amine or guanidine nor a simple N-acetyl grouping. However, 8 was a poor inhibitor of influenza B neuraminidase. In the present study we further evaluated 8 as an inhibitor of human influenza A NA isolates, and it was effective against N2NA but found to be 160-fold less active against N1NA. We also synthesized analogues of 8 involving moderate modifications of essential substituents on the pyrrolidinone ring. Specifically, the aminomethyl (9), hydroxyethyl (10), and aminoethyl (11) analogues were prepared. Only the most conservative change (compound 9) resulted in continued effective inhibition of influenza A, in addition to a noteworthy increase in the activity of 9 for N1NA. The effectiveness of 9 against influenza B neuraminidase was furthermore improved 10-fold relative to 8, but this activity remained 50-fold poorer than for type A NA.
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Affiliation(s)
- Wayne J Brouillette
- Department of Chemistry, 901 14th Street South, CHEM 201, The University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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Neuraminic acid — Structure, Chemistry, Biological Activity. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1572-5995(02)80035-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Smith BJ, Colman PM, Von Itzstein M, Danylec B, Varghese JN. Analysis of inhibitor binding in influenza virus neuraminidase. Protein Sci 2001; 10:689-96. [PMID: 11274459 PMCID: PMC2373964 DOI: 10.1110/ps.41801] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
2,3-didehydro-2-deoxy-N:-acetylneuraminic acid (DANA) is a transition state analog inhibitor of influenza virus neuraminidase (NA). Replacement of the hydroxyl at the C9 position in DANA and 4-amino-DANA with an amine group, with the intention of taking advantage of an increased electrostatic interaction with a conserved acidic group in the active site to improve inhibitor binding, significantly reduces the inhibitor activity of both compounds. The three-dimensional X-ray structure of the complexes of these ligands and NA was obtained to 1.4 A resolution and showed that both ligands bind isosterically to DANA. Analysis of the geometry of the ammonium at the C4 position indicates that Glu119 may be neutral when these ligands bind. A computational analysis of the binding energies indicates that the substitution is successful in increasing the energy of interaction; however, the gains that are made are not sufficient to overcome the energy that is required to desolvate that part of the ligand that comes in contact with the protein.
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Affiliation(s)
- B J Smith
- Biomolecular Research Institute, Parkville, Victoria 3052, Australia.
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26
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Kiefel MJ, von Itzstein M. Influenza virus sialidase: a target for drug discovery. PROGRESS IN MEDICINAL CHEMISTRY 2000; 36:1-28. [PMID: 10818670 DOI: 10.1016/s0079-6468(08)70044-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Affiliation(s)
- M J Kiefel
- Department of Medicinal Chemistry, Monash University, Parkville, Victoria, Australia
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27
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Finley JB, Atigadda VR, Duarte F, Zhao JJ, Brouillette WJ, Air GM, Luo M. Novel aromatic inhibitors of influenza virus neuraminidase make selective interactions with conserved residues and water molecules in the active site. J Mol Biol 1999; 293:1107-19. [PMID: 10547289 DOI: 10.1006/jmbi.1999.3180] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The active site of type A or B influenza virus neuraminidase is composed of 11 conserved residues that directly interact with the substrate, sialic acid. An aromatic benzene ring has been used to replace the pyranose of sialic acid in our design of novel neuraminidase inhibitors. A bis(hydroxymethyl)pyrrolidinone ring was constructed in place of the N-acetyl group on the sialic acid. The hydroxymethyl groups replace two active site water molecules, which resulted in the high affinity of the nanomolar inhibitors. However, these inhibitors have greater potency for type A influenza virus than for type B influenza virus. To resolve the differences, we determined the X-ray crystal structure of three benzoic acid substituted inhibitors bound to the active site of B/Lee/40 neuraminidase. The investigation of a hydrophobic aliphatic group and a hydrophilic guanidino group on the aromatic inhibitors shows changes in the interaction with the active site residue Glu275. The results provide an explanation for the difference in efficacy of these inhibitors against types A and B viruses, even though the 11 active site residues of the neuraminidase are conserved.
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Affiliation(s)
- J B Finley
- Center for Macromolecular Crystallography, Department of Microbiology, University of Alabama, Birmingham, AL 35294, USA
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28
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Affiliation(s)
- G M Air
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City 73190, USA
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29
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Atigadda VR, Brouillette WJ, Duarte F, Babu YS, Bantia S, Chand P, Chu N, Montgomery JA, Walsh DA, Sudbeck E, Finley J, Air GM, Luo M, Laver GW. Hydrophobic benzoic acids as inhibitors of influenza neuraminidase. Bioorg Med Chem 1999; 7:2487-97. [PMID: 10632058 DOI: 10.1016/s0968-0896(99)00197-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Neuraminidase (NA) plays a critical role in the life cycle of influenza virus and is a target for new therapeutic agents. A new benzoic acid inhibitor (11) containing a lipophilic side chain at C-3 and a guanidine at C-5 was synthesized. The X-ray structure of 4-(N-acetylamino)-5-guanidino-3-(3-pentyloxy)benzoic acid in complex with NA revealed that the lipophilic side chain binds in a newly created hydrophobic pocket formed by the movement of Glu 278 to interact with Arg 226, whereas the guanidine of 11 interacts in a negatively charged pocket created by Asp 152, Glu 120 and Glu 229. Compound 11 was highly selective for type A (H2N2) influenza NA (IC50 1 microM) over type B (B/Lee/40) influenza NA (IC50 500 microM).
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Affiliation(s)
- V R Atigadda
- Department of Chemistry, University of Alabama at Birmingham, 35294, USA
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30
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Brouillette WJ, Atigadda VR, Luo M, Air GM, Babu YS, Bantia S. Design of benzoic acid inhibitors of influenza neuraminidase containing a cyclic substitution for the N-acetyl grouping. Bioorg Med Chem Lett 1999; 9:1901-6. [PMID: 10450950 DOI: 10.1016/s0960-894x(99)00318-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A 2-pyrrolidinone ring containing a single hydroxymethyl side chain effectively replaces the N-acetylamino group of 4-(N-acetylamino)-3-guanidinobenzoic acid, a low micromolar inhibitor of influenza neuraminidase. This novel structural template affords new opportunities to evolve more potent benzoic acid inhibitors.
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Affiliation(s)
- W J Brouillette
- Department of Chemistry, University of Alabama at Birmingham, 35294, USA
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31
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Colacino JM, Staschke KA, Laver WG. Approaches and strategies for the treatment of influenza virus infections. Antivir Chem Chemother 1999; 10:155-85. [PMID: 10480736 DOI: 10.1177/095632029901000402] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Influenza A and B viruses belong to the Orthomyxoviridae family of viruses. These viruses are responsible for severe morbidity and significant excess mortality each year. Infection with influenza viruses usually leads to respiratory involvement and can result in pneumonia and secondary bacterial infections. Vaccine approaches to the prophylaxis of influenza virus infections have been problematic owing to the ability of these viruses to undergo antigenic shift by exchanging genomic segments or by undergoing antigenic drift, consisting of point mutations in the haemagglutinin (HA) and neuraminidase (NA) genes as a result of an error-prone viral polymerase. Historically, antiviral approaches for the therapy of both influenza A and B viruses have been largely unsuccessful until the elucidation of the X-ray crystallographic structure of the viral NA, which has permitted structure-based drug design of inhibitors of this enzyme. In addition, recent advances in the elucidation of the structure and complex function of influenza HA have resulted in the discovery of a number of diverse compounds that target this viral protein. This review article will focus largely on newer antiviral agents including those that inhibit the influenza virus NA and HA. Other novel approaches that have entered clinical trials or been considered for their clinical utility will be mentioned.
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Affiliation(s)
- J M Colacino
- Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, IN 46285, USA.
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32
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Howes PD, Cleasby A, Evans DN, Feilden H, Smith PW, Sollis SL, Taylor N, Wonacott AJ. 4-Acetylamino-3-(imidazol-1-yl)-benzoic acids as novel inhibitors of influenza sialidase. Eur J Med Chem 1999. [DOI: 10.1016/s0223-5234(99)80055-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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33
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Abstract
Epidemic influenza continues to be associated with significant morbidity in the general population, and mortality in the elderly and other high risk patients. Although the case fatality rate averages less than 0.01%, tens of thousands of deaths occur each year. Control through immunisation programmes has not been possible due to incomplete protective efficacy and antigenic variations that occur frequently. Currently available anti-influenza medications (amantadine and rimantadine) have had limited success due to underutilisation, lack of activity against influenza B, the rapid development of viral resistance to the drugs, and adverse effects. A new class of antiviral agents designed to inhibit influenza neuraminidase, an important surface glycoprotein, is currently under active development for use in the prophylaxis and treatment of influenza A and B infections. Two of these compounds, zanamivir (GG167) and GS4104 (the ethyl ester prodrug of GS4071) have reached clinical trials. Most studies of zanamivir have involved topical administration by inhalation of dry powder aerosols and/or intranasal doses of aqueous solutions. These routes rapidly provide high local concentrations at the sites of delivery. GS4104 is administered orally, which allows for greater ease of administration, and probably more uniform distribution of the parent compound GS4071 in the respiratory tract. Both have shown potent inhibitory activity against influenza in animal models and experimental human influenza with excellent tolerability profiles. Zanamivir treatment has been shown to reduce the severity and duration of naturally occurring, uncomplicated influenza illness in adults. Clinical resistance to these drugs has not been recognised as a significant problem to date, although strains resistant to each agent have been produced in the laboratory. This class of agents shows considerable promise as a novel approach to prophylaxis and treatment of influenza infections. Ongoing studies should provide the data needed to allow the addition of 1 or more of the neuraminidase inhibitors to the clinician's anti-influenza armamentarium.
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Affiliation(s)
- D P Calfee
- Department of Internal Medicine, University of Virginia Health Sciences Center, Charlottesville, USA
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34
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Bantia S, Ghate AA, Ananth SL, Babu YS, Air GM, Walsh GM. Generation and characterization of a mutant of influenza A virus selected with the neuraminidase inhibitor BCX-140. Antimicrob Agents Chemother 1998; 42:801-7. [PMID: 9559786 PMCID: PMC105545 DOI: 10.1128/aac.42.4.801] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/1997] [Accepted: 01/13/1998] [Indexed: 02/07/2023] Open
Abstract
Influenza neuraminidase (NA) plays an important role in viral replication, and characterization of viruses resistant to NA inhibitors will help elucidate the role of active-site residues. This information will assist in designing better inhibitors targeted to essential active-site residues that cannot generate drug-resistant mutations. In the present study we used the benzoic acid-based inhibitor BCX-140 to select and characterize resistant viruses. BCX-140 binds to the NA active site in an orientation that is opposite that of a sialic acid-based compound, 4-guanidino-2,4-dideoxy-2,3-dehydro-N-acetylneuraminic acid (GANA). Thus, the guanidino group of BCX-140 binds to Glu-276, whereas in GANA the guanidino group binds to Glu-119. We passaged influenza A/Singapore/1/57 (H2N2) in Madin-Darby canine kidney cells in the presence of BCX-140, and virus resistant to this inhibitor was selected after six passages. The NA of this mutant was still sensitive to inhibition by BCX-140. However, the mutant virus was resistant to BCX-140 in plaque and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Sequence analysis of hemagglutinin (HA) and NA genes revealed changes in both, although none were in the active site of the NA. Depending on the method of selection of the resistant virus, two types of changes associated with the sialic acid binding site were seen in the HA. One is a change in HA1 of Ala-133 to Thr, a residue close to the binding site, while the other change was Arg-132 of HA1 to Gln, which in HA1 of serotype H3 is a sialic acid contact (Asn-137). Binding studies revealed that both types of resistant viruses had reduced receptor binding affinity compared to that of the wild type. Thus, resistance to BCX-140 was generated by modifying the HA. NA active-site residue 276 may be essential for activity, and thus, it cannot be changed to generate resistance. However, drug-induced changes in the HA can result in a virus that is less dependent on NA activity for growth in cells and, hence, resistant to NA inhibitors.
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Affiliation(s)
- S Bantia
- BioCryst Pharmaceuticals, Inc., Birmingham, Alabama 35244, USA.
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35
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Abstract
The threat of a catastrophic outbreak of influenza is ever present. Vaccines are only partially effective and the two compounds, amantidine and rimantidine, used clinically against influenza A cause side-effects and rapid viral resistance. Recent advances bring hope that specific and potent drugs against influenza may soon be available in the clinic. These compounds were designed to inhibit influenza neuraminidase (NA), one of the viral coat glycoproteins, using the crystal structure of NA which was first published in 1983. In this review, the application of structure-based drug design approaches to the design of anti-influenza agents targeted at NA and haemagglutinin (HA), the other viral surface glycoprotein, is discussed.
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Affiliation(s)
- R C Wade
- Structural Biology Programme, European Molecular Biology Laboratory, Heidelberg, Germany.
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36
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Cummins CL, O'Neil WM, Soo EC, Lloyd DK, Wainer IW. Determination of p-aminosalicylic acid and its N-acetylated metabolite in human urine by capillary zone electrophoresis as a measure of in vivo N-acetyltransferase 1 activity. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1997; 697:283-8. [PMID: 9342682 DOI: 10.1016/s0378-4347(97)00084-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A capillary zone electrophoresis method has been developed for the determination of p-aminosalicylic acid (PAS) and its metabolite, N-acetyl-p-aminosalicylic acid (N-acetyl-PAS), in urine. A linear relationship was observed between time-normalized peak area and the concentration of the parent and metabolite with correlation coefficients greater than 0.9990. The method could be applied to the determination of PAS and N-acetyl-PAS in human urine without any sample pretreatment. A good separation of the analytes is achieved in a run time of 12 min (15 min total, including capillary wash). Using PAS as a probe for N-acetyltransferase 1 activity, 20 healthy volunteers were phenotyped after oral administration of a 1 g dose. The preliminary results seem to indicate a bimodal distribution of N-acetyl-PAS/PAS molar ratios.
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Affiliation(s)
- C L Cummins
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
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37
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Sudbeck EA, Jedrzejas MJ, Singh S, Brouillette WJ, Air GM, Laver WG, Babu YS, Bantia S, Chand P, Chu N, Montgomery JA, Walsh DA, Luo M. Guanidinobenzoic acid inhibitors of influenza virus neuraminidase. J Mol Biol 1997; 267:584-94. [PMID: 9126840 DOI: 10.1006/jmbi.1996.0885] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The active site of influenza virus neuraminidase (NA) is formed by 11 universally conserved residues. A guanidino group incorporated into two unrelated NA inhibitors was previously reported to occupy different negatively charged sites in the NA active site, A new inhibitor containing two guanidino groups was synthesized in order to utilize both sites in an attempt to acquire a combined increase in affinity. The X-ray crystal structures of the complexes show that the expected increase in affinity could not be achieved even though the added guanidino group binds to the negatively charged site as designed. This suggests that the ligand affinity to the target protein is contributed both from ligand-protein interactions and solvation/conformation energy of the ligand.
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Affiliation(s)
- E A Sudbeck
- Center for Macromolecular Crystallography, University of Alabama at Birmingham, USA
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38
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Abstract
The structure-based design of a potent inhibitor of the influenza-virus neuraminidase (sialidase) is one of the outstanding successes of rational drug design. Recent clinical trials of the drug have stimulated many companies to seek a share of the potentially huge flu market. Sialidases, however, are involved in the pathogenesis of a whole range of other diseases, so perhaps the knowledge and expertise gained from the influenza story can be used in the design of other drugs, given that they all share certain structural features.
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Affiliation(s)
- G Taylor
- School of Biology and Biochemistry, University of Bath, Claverton Down, UK.
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39
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von Itzstein M, Colman P. Design and synthesis of carbohydrate-based inhibitors of protein-carbohydrate interactions. Curr Opin Struct Biol 1996; 6:703-9. [PMID: 8913694 DOI: 10.1016/s0959-440x(96)80038-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Our understanding of carbohydrate-protein interactions has significantly advanced over the past two years. In particular, a healthy amount of literature has appeared on selectins and their relevant ligands. A significant number of carbohydrate-metabolizing enzyme crystal structures have been solved which provide useful starting points for computer-assisted drug design. Some of these proteins have been implicated either directly or indirectly in playing roles in human-disease states, for example, in inflammation, in diabetes and its complications, and in microorganism-induced diseases such as influenza and cholera.
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Affiliation(s)
- M von Itzstein
- Department of Medicinal Chemistry, Victorian College of Pharmacy, Monash University, Parkville, Australia.
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40
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Sialidase inhibitors related to GG167: Synthesis of analogues via an inverse demand hetero Diels Alder reaction. Tetrahedron Lett 1996. [DOI: 10.1016/0040-4039(96)01408-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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41
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Meanwell NA, Krystal M. Taking aim at a moving target — inhibitors of influenza virus Part 2: viral replication, packaging and release. Drug Discov Today 1996. [DOI: 10.1016/1359-6446(96)10035-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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42
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Sollis SL, Smith PW, Howes PD, Cherry PC, Bethell RC. Novel inhibitors of influenza sialidase related to GG167 Synthesis of 4-amino and guanidino-4H-pyran-2-carboxylic acid-6-propylamides; selective inhibitors of influenza a virus sialidase. Bioorg Med Chem Lett 1996. [DOI: 10.1016/0960-894x(96)00318-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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