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Kumar I, Sagar A, Dhiman K, Bethel CR, Hujer AM, Carifi J, Ashish, Bonomo RA. Insights into dynamic changes in ADC-7 and P99 cephalosporinases using small angle x-ray scattering (SAXS). J Biomol Struct Dyn 2024; 42:7541-7553. [PMID: 37578017 DOI: 10.1080/07391102.2023.2240427] [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: 03/22/2023] [Accepted: 07/18/2023] [Indexed: 08/15/2023]
Abstract
To counter the emergence of β-lactamase (BL) mediated resistance, design of new β-lactamase inhibitors (BLIs) is critical. Many high-resolution crystallographic structures of BL complexed with BLIs are available. However, their impact on BLI design is struggling to keep pace with novel and emerging variants. Small angle x-ray scattering (SAXS) in combination with molecular modeling is a useful tool to determine dynamic structures of macromolecules in solution. An important application of SAXS is to determine the conformational changes that occur when BLI bind to BL. To probe if conformational dynamics occur in class C cephalosporinases, we studied SAXS profiles of two clinically relevant class C β-lactamases, Acinetobacter baumannii ADC-7 and Enterobacter cloacae P99 in apo format complexed with BLIs. Importantly, SAXS data analysis demonstrated that in solution, these representative class C enzymes remain monomeric and did not show the associated assemblies that were seen in various crystal structures. SAXS data acquired for ADC-7 and P99, in apo and inhibitor bound states, clearly showed that these enzymes undergo detectable conformational changes, and these class C β-lactamases also close upon binding inhibitors as does BlaC. Further analysis revealed that addition of inhibitor led to the compacting of a range of residues around the active site, indicating that the conformational changes that both P99 and ADC-7 undergo are central to inhibitor recognition and efficacy. Our findings support the importance of exploring conformational changes using SAXS analysis in the design of future BLIs.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Ish Kumar
- Department of Chemistry, Biochemistry & Physics, Fairleigh Dickinson University, Teaneck, NJ, USA
| | - Amin Sagar
- Centre de Biochimie Structurale (CBS), Montpellier, France
| | - Kanika Dhiman
- GNR Advanced Protein Centre, CSIR-Institute of Microbial Technology, Chandigarh, India
| | - Christopher R Bethel
- Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, USA
| | - Andrea M Hujer
- Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, USA
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Justin Carifi
- Department of Chemistry, Biochemistry & Physics, Fairleigh Dickinson University, Teaneck, NJ, USA
| | - Ashish
- GNR Advanced Protein Centre, CSIR-Institute of Microbial Technology, Chandigarh, India
| | - Robert A Bonomo
- Research Service, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, USA
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA
- Clinician Scientist Investigator, Louis Stokes Cleveland Department of Veterans Affairs Medical Center, Cleveland, OH, USA
- Departments of Biochemistry, Pharmacology, Molecular Biology and Microbiology, Proteomics and Bioinformatics, Case Western Reserve University School of Medicine, Cleveland, OH, USA
- CWRU-Cleveland VAMC Center for Antimicrobial Resistance and Epidemiology (Case VA CARES, Cleveland, OH, USA
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2
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Tilvawala R, Nemmara VV, Reyes AC, Sorvillo N, Salinger AJ, Cherpokova D, Fukui S, Gutch S, Wagner D, Thompson PR. The role of SERPIN citrullination in thrombosis. Cell Chem Biol 2021; 28:1728-1739.e5. [PMID: 34352225 DOI: 10.1016/j.chembiol.2021.07.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 04/29/2021] [Accepted: 07/08/2021] [Indexed: 02/01/2023]
Abstract
Aberrant protein citrullination is associated with many pathologies; however, the specific effects of this modification remain unknown. We have previously demonstrated that serine protease inhibitors (SERPINs) are highly citrullinated in rheumatoid arthritis (RA) patients. These citrullinated SERPINs include antithrombin, antiplasmin, and t-PAI, which regulate the coagulation and fibrinolysis cascades. Notably, citrullination eliminates their inhibitory activity. Here, we demonstrate that citrullination of antithrombin and t-PAI impairs their binding to their cognate proteases. By contrast, citrullination converts antiplasmin into a substrate. We recapitulate the effects of SERPIN citrullination using in vitro plasma clotting and fibrinolysis assays. Moreover, we show that citrullinated antithrombin and antiplasmin are increased and decreased in a deep vein thrombosis (DVT) model, accounting for how SERPIN citrullination shifts the equilibrium toward thrombus formation. These data provide a direct link between increased citrullination and the risk of thrombosis in autoimmunity and indicate that aberrant SERPIN citrullination promotes pathological thrombus formation.
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Affiliation(s)
- Ronak Tilvawala
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA; Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045, USA
| | - Venkatesh V Nemmara
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA; Department of Chemistry, Rowan University, Glassboro, NJ 08028, USA
| | - Archie C Reyes
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA
| | - Nicoletta Sorvillo
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Ari J Salinger
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA; Department of Chemistry, Boston College, Chestnut Hill, MA 02467, USA
| | - Deya Cherpokova
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Saeko Fukui
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Sarah Gutch
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Denisa Wagner
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA 02115, USA; Whitman Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Paul R Thompson
- Department of Biochemistry and Pharmacology, University of Massachusetts Medical School, LRB 826, 364 Plantation Street, Worcester, MA 01605, USA.
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3
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Laws M, Shaaban A, Rahman KM. Antibiotic resistance breakers: current approaches and future directions. FEMS Microbiol Rev 2020; 43:490-516. [PMID: 31150547 PMCID: PMC6736374 DOI: 10.1093/femsre/fuz014] [Citation(s) in RCA: 149] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 05/30/2019] [Indexed: 12/15/2022] Open
Abstract
Infections of antibiotic-resistant pathogens pose an ever-increasing threat to mankind. The investigation of novel approaches for tackling the antimicrobial resistance crisis must be part of any global response to this problem if an untimely reversion to the pre-penicillin era of medicine is to be avoided. One such promising avenue of research involves so-called antibiotic resistance breakers (ARBs), capable of re-sensitising resistant bacteria to antibiotics. Although some ARBs have previously been employed in the clinical setting, such as the β-lactam inhibitors, we posit that the broader field of ARB research can yet yield a greater diversity of more effective therapeutic agents than have been previously achieved. This review introduces the area of ARB research, summarises the current state of ARB development with emphasis on the various major classes of ARBs currently being investigated and their modes of action, and offers a perspective on the future direction of the field.
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Affiliation(s)
- Mark Laws
- Institute of Pharmaceutical Sciences, School of Cancer and Pharmaceutical Sciences, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London, SE1 9NH
| | - Ali Shaaban
- Institute of Pharmaceutical Sciences, School of Cancer and Pharmaceutical Sciences, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London, SE1 9NH
| | - Khondaker Miraz Rahman
- Institute of Pharmaceutical Sciences, School of Cancer and Pharmaceutical Sciences, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London, SE1 9NH
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4
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Specificity of extended O-aryloxycarbonyl hydroxamates as inhibitors of a class C β-lactamase. Bioorg Med Chem 2019; 27:1430-1436. [PMID: 30792103 DOI: 10.1016/j.bmc.2019.02.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 02/06/2019] [Indexed: 11/22/2022]
Abstract
Class C β-lactamases have previously been shown to be efficiently inactivated by O-aryloxycarbonyl hydroxamates. O-Phenoxycarbonyl-N-benzyloxycarbonylhydroxylamine (1) and O-phenoxycarbonyl-N-(R)-[(4-amino-4-carboxy-1-butyl)oxycarbonyl]hydroxylamine (2), for example, were found to be effective inactivators. The present paper describes a structure-activity study of these molecules to better define the important structural elements for high inhibitory activity. The results show that a well-positioned hydrophobic element (which may interact with the Tyr221 residue of the enzyme) and a negatively charged element, e.g. a carboxylate group (which may interact with Arg204), are required for high reactivity with the enzyme. The new compounds were found to inactivate by forming a carbonyl cross-linked enzyme (probably Ser64OCONHLys 315) as for 1 rather than the inert hydroxamoyl derivative observed with 2.
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5
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Gao D, Jin F, Yan X, Zare RN. Selective Synthesis in Microdroplets of 2-Phenyl-2,3-dihydrophthalazine-1,4-dione from Phenyl Hydrazine with Phthalic Anhydride or Phthalic Acid. Chemistry 2018; 25:1466-1471. [PMID: 30417449 DOI: 10.1002/chem.201805585] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Indexed: 01/10/2023]
Abstract
Pyridazine derivatives are privileged structures because of their potential biological and optical properties. Traditional synthetic methods usually require acid or base as a catalyst under reflux conditions with reaction times ranging from hours to a few days or require microwave assistance to induce the reaction. Herein, this work presents the accelerated synthesis of a pyridazine derivative, 2-phenyl-2,3-dihydrophthalazine-1,4-dione (PDHP), in electrosprayed microdroplets containing an equimolar mixture of phenyl hydrazine and phthalic anhydride or phthalic acid. This reaction occurred on the submillisecond timescale with good yield (over 90 % with the choice of solvent) without using an external catalyst at room temperature. In sharp contrast to the bulk reaction of obtaining a mixture of two products, the reaction in confined microdroplets yields only the important six-membered heterocyclic product PDHP. Results indicated that surface reactions in microdroplets with low pH values cause selectivity, acceleration, and high yields.
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Affiliation(s)
- Dan Gao
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305-5080, USA.,State Key Laboratory of Chemical Oncogenomics the Graduate School at, Shenzhen, Tsinghua University, Tsinghua Campus, The University Town, Shenzhen, 518055, P. R. China
| | - Feng Jin
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305-5080, USA
| | - Xin Yan
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305-5080, USA
| | - Richard N Zare
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305-5080, USA
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6
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Kim TK, Kim JE, Youn UJ, Han SJ, Kim IC, Cho CG, Yim JH. Total Syntheses of Lobaric Acid and Its Derivatives from the Antarctic Lichen Stereocaulon alpinum. JOURNAL OF NATURAL PRODUCTS 2018; 81:1460-1467. [PMID: 29878768 DOI: 10.1021/acs.jnatprod.8b00227] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The first total syntheses of the natural products lobaric acid (1) and its derivatives isolated from the Antarctic lichen Stereocaulon alpinum are reported in this study. Lobarin (3), with a pseudodepsidone structure, was synthesized first in 11 steps by utilizing an Ullmann aryl ether coupling reaction, and lobaric acid was synthesized in an additional three steps by a seven-membered lactonization reaction. Various derivatives were also obtained from the prepared lobaric acid, and the synthetic compounds exhibited significant PTP1B inhibitory activities.
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Affiliation(s)
- Tai Kyoung Kim
- Division of Life Sciences , Korea Polar Research Institute, KOPRI , Incheon 406-840 , Republic of Korea
- Department of Chemistry , Hanyang University , 222 Wangshimni-ro, Seongdong-gu, Seoul 04763 , Republic of Korea
| | - Joung Eun Kim
- Division of Life Sciences , Korea Polar Research Institute, KOPRI , Incheon 406-840 , Republic of Korea
| | - Ui Joung Youn
- Division of Life Sciences , Korea Polar Research Institute, KOPRI , Incheon 406-840 , Republic of Korea
| | - Se Jong Han
- Division of Life Sciences , Korea Polar Research Institute, KOPRI , Incheon 406-840 , Republic of Korea
| | - Il-Chan Kim
- Division of Life Sciences , Korea Polar Research Institute, KOPRI , Incheon 406-840 , Republic of Korea
| | - Cheon-Gyu Cho
- Department of Chemistry , Hanyang University , 222 Wangshimni-ro, Seongdong-gu, Seoul 04763 , Republic of Korea
| | - Joung Han Yim
- Division of Life Sciences , Korea Polar Research Institute, KOPRI , Incheon 406-840 , Republic of Korea
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7
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Dragan A, Jones DH, Kennedy AR, Tomkinson NCO. Stereoselective Synthesis of Alkylidene Phthalides. Org Lett 2016; 18:3086-9. [PMID: 27311815 DOI: 10.1021/acs.orglett.6b01203] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The N,O-diacylhydroxylamine derivative 4 has been prepared and its reactivity with nucleophiles investigated. On reaction with lithium enolates of cyclic or acyclic ketones, 4 is converted stereoselectively to the corresponding alkylidene phthalide. The stereochemical outcome of the transformation can be modified by changing the polarity of the reaction medium and the products isomerized under acidic conditions.
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Affiliation(s)
- Andrei Dragan
- WestCHEM, Department of Pure and Applied Chemistry, Thomas Graham Building, University of Strathclyde , 295 Cathedral Street, Glasgow G1 1XL, U.K
| | - D Heulyn Jones
- WestCHEM, Department of Pure and Applied Chemistry, Thomas Graham Building, University of Strathclyde , 295 Cathedral Street, Glasgow G1 1XL, U.K
| | - Alan R Kennedy
- WestCHEM, Department of Pure and Applied Chemistry, Thomas Graham Building, University of Strathclyde , 295 Cathedral Street, Glasgow G1 1XL, U.K
| | - Nicholas C O Tomkinson
- WestCHEM, Department of Pure and Applied Chemistry, Thomas Graham Building, University of Strathclyde , 295 Cathedral Street, Glasgow G1 1XL, U.K
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8
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Yang S, Liao D, Tian X, Lei X. Access to the 2H-Tetrahydro-4,6-dioxo-1,2-oxazine Ring System from Nitrone via a Tandem Nucleophilic Addition and Transesterification Reaction. Org Lett 2016; 18:376-9. [DOI: 10.1021/acs.orglett.5b03374] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Shaoqiang Yang
- School
of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | - Daohong Liao
- School
of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | - Xiaoqi Tian
- School
of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | - Xiaoguang Lei
- School
of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
- Beijing
National Laboratory of Molecular Sciences, Key Laboratory of Bioorganic
Chemistry and Molecular Engineering of Ministry of Education, Department
of Chemical Biology, College of Chemistry and Molecular Engineering,
Synthetic and Functional Biolmolecules Center, and Center for Life
Sciences, Peking University, Beijing 100871, China
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9
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Gill EE, Franco OL, Hancock REW. Antibiotic adjuvants: diverse strategies for controlling drug-resistant pathogens. Chem Biol Drug Des 2015; 85:56-78. [PMID: 25393203 PMCID: PMC4279029 DOI: 10.1111/cbdd.12478] [Citation(s) in RCA: 209] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 10/31/2014] [Accepted: 11/03/2014] [Indexed: 01/08/2023]
Abstract
The growing number of bacterial pathogens that are resistant to numerous antibiotics is a cause for concern around the globe. There have been no new broad-spectrum antibiotics developed in the last 40 years, and the drugs we have currently are quickly becoming ineffective. In this article, we explore a range of therapeutic strategies that could be employed in conjunction with antibiotics and may help to prolong the life span of these life-saving drugs. Discussed topics include antiresistance drugs, which are administered to potentiate the effects of current antimicrobials in bacteria where they are no longer (or never were) effective; antivirulence drugs, which are directed against bacterial virulence factors; host-directed therapies, which modulate the host's immune system to facilitate infection clearance; and alternative treatments, which include such therapies as oral rehydration for diarrhea, phage therapy, and probiotics. All of these avenues show promise for the treatment of bacterial infections and should be further investigated to explore their full potential in the face of a postantibiotic era.
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Affiliation(s)
- Erin E Gill
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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10
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An H, Statsyuk AV. An inhibitor of ubiquitin conjugation and aggresome formation. Chem Sci 2015; 6:5235-5245. [PMID: 28717502 PMCID: PMC5500945 DOI: 10.1039/c5sc01351h] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 06/22/2015] [Indexed: 11/21/2022] Open
Abstract
Proteasome inhibitors have revolutionized the treatment of multiple myeloma, and validated the therapeutic potential of the ubiquitin proteasome system (UPS). It is believed that in part, proteasome inhibitors elicit their therapeutic effect by inhibiting the degradation of misfolded proteins, which is proteotoxic and causes cell death. In spite of these successes, proteasome inhibitors are not effective against solid tumors, thus necessitating the need to explore alternative approaches. Furthermore, proteasome inhibitors lead to the formation of aggresomes that clear misfolded proteins via the autophagy-lysosome degradation pathway. Importantly, aggresome formation depends on the presence of polyubiquitin tags on misfolded proteins. We therefore hypothesized that inhibitors of ubiquitin conjugation should inhibit both degradation of misfolded proteins, and ubiquitin dependent aggresome formation, thus outlining the path forward toward more effective anticancer therapeutics. To explore the therapeutic potential of targeting the UPS to treat solid cancers, we have developed an inhibitor of ubiquitin conjugation (ABP A3) that targets ubiquitin and Nedd8 E1 enzymes, enzymes that are required to maintain the activity of the entire ubiquitin system. We have shown that ABP A3 inhibits conjugation of ubiquitin to intracellular proteins and prevents the formation of cytoprotective aggresomes in A549 lung cancer cells. Furthermore, ABP A3 induces activation of the unfolded protein response and apoptosis. Thus, similar to proteasome inhibitors MG132, bortezomib, and carfilzomib, ABP A3 can serve as a novel probe to explore the therapeutic potential of the UPS in solid and hematological malignancies.
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Affiliation(s)
- Heeseon An
- Department of Chemistry , Center for Molecular Innovation and Drug Discovery , Chemistry of Life Processes Institute , Northwestern University , Silverman Hall, 2145 Sheridan Road , Evanston , Illinois 60208 , USA
| | - Alexander V Statsyuk
- Department of Chemistry , Center for Molecular Innovation and Drug Discovery , Chemistry of Life Processes Institute , Northwestern University , Silverman Hall, 2145 Sheridan Road , Evanston , Illinois 60208 , USA
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11
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Izydore RA, Jones J, Mogesa B, Swain IN, Davis-Ward RG, Daniels DL, Kpakima F, Spaulding-Phifer S. Synthesis of 3,5-isoxazolidinediones and 1H-2,3-benzoxazine-1,4(3H)-diones from aliphatic oximes and dicarboxylic acid chlorides. J Org Chem 2014; 79:2874-82. [PMID: 24620711 PMCID: PMC3985836 DOI: 10.1021/jo402708j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Indexed: 11/30/2022]
Abstract
The synthesis of the title compounds was carried out by reacting dicarboxylic acid chlorides with oximes in the presence of excess triethylamine. Disubstituted malonyl chlorides gave 2-alkenyl-4,4-dialkyl-3,5-isoxazolidinediones (8a-f) and 2,2'-ethylidene-bis[4,4-dialkyl-3,5-isoxazolidinedione]s (9a-f). Compounds 9 were formed from 8 and its N-unsubstituted 3,5-isoxazolidinedione decomposition product. Phthaloyl chlorides reacted with acetone oxime to yield 3-(1-methylethenyl)-1H-2,3-benzoxazine-1,4(3H)-diones (16a-e). Products 16 spontaneously decomposed to give N-unsubstituted 1H-2,3-benzoxazine-1,4(3H)-diones (17a-e) at rates that were dependent on temperature and solvent. Kinetic studies showed that two of the compounds decomposed by zero-order kinetics under neutral conditions. Butanedioyl chloride did not produce a cyclic product.
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Affiliation(s)
| | - Joseph
T. Jones
- Department
of Chemistry, North Carolina Central University, Durham, North Carolina 27707, United States
| | - Benjamin Mogesa
- Department
of Chemistry, North Carolina Central University, Durham, North Carolina 27707, United States
| | - Ira N. Swain
- Department
of Chemistry, North Carolina Central University, Durham, North Carolina 27707, United States
| | - Ronda G. Davis-Ward
- Department
of Chemistry, North Carolina Central University, Durham, North Carolina 27707, United States
| | - Dwayne L. Daniels
- Department
of Chemistry, North Carolina Central University, Durham, North Carolina 27707, United States
| | - Felicia
Frazier Kpakima
- Department
of Chemistry, North Carolina Central University, Durham, North Carolina 27707, United States
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