1
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Reisman BJ, Guo H, Ramsey HE, Wright MT, Reinfeld BI, Ferrell PB, Sulikowski GA, Rathmell WK, Savona MR, Plate L, Rubinstein JL, Bachmann BO. Apoptolidin family glycomacrolides target leukemia through inhibition of ATP synthase. Nat Chem Biol 2022; 18:360-367. [PMID: 34857958 PMCID: PMC8967781 DOI: 10.1038/s41589-021-00900-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 09/17/2021] [Indexed: 11/11/2022]
Abstract
Cancer cells have long been recognized to exhibit unique bioenergetic requirements. The apoptolidin family of glycomacrolides are distinguished by their selective cytotoxicity towards oncogene-transformed cells, yet their molecular mechanism remains uncertain. We used photoaffinity analogs of the apoptolidins to identify the F1 subcomplex of mitochondrial ATP synthase as the target of apoptolidin A. Cryogenic electron microscopy (cryo-EM) of apoptolidin and ammocidin-ATP synthase complexes revealed a novel shared mode of inhibition that was confirmed by deep mutational scanning of the binding interface to reveal resistance mutations which were confirmed using CRISPR-Cas9. Ammocidin A was found to suppress leukemia progression in vivo at doses that were tolerated with minimal toxicity. The combination of cellular, structural, mutagenesis, and in vivo evidence defines the mechanism of action of apoptolidin family glycomacrolides and establishes a path to address oxidative phosphorylation-dependent cancers.
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Affiliation(s)
- Benjamin J. Reisman
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA.,Medical Scientist Training Program, Vanderbilt University, Nashville, Tennessee, USA
| | - Hui Guo
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Haley E. Ramsey
- Department of Medicine, Division of Hematology/Oncology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Madison T. Wright
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA
| | - Bradley I. Reinfeld
- Medical Scientist Training Program, Vanderbilt University, Nashville, Tennessee, USA.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.,Cancer Biology Program, Vanderbilt University, Nashville, Tennessee, USA
| | - P. Brent Ferrell
- Department of Medicine, Division of Hematology/Oncology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Cancer Biology Program, Vanderbilt University, Nashville, Tennessee, USA
| | - Gary A. Sulikowski
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA
| | - W. Kimryn Rathmell
- Department of Medicine, Division of Hematology/Oncology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Cancer Biology Program, Vanderbilt University, Nashville, Tennessee, USA
| | - Michael R. Savona
- Department of Medicine, Division of Hematology/Oncology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Cancer Biology Program, Vanderbilt University, Nashville, Tennessee, USA
| | - Lars Plate
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA.,Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - John L. Rubinstein
- Molecular Medicine Program, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.,Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Brian O. Bachmann
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA.,Correspondence to:
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2
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Ren L, Ding S, Song Y, Li B, Ramanathan M, Co J, Amieva MR, Khavari PA, Greenberg HB. Profiling of rotavirus 3'UTR-binding proteins reveals the ATP synthase subunit ATP5B as a host factor that supports late-stage virus replication. J Biol Chem 2019; 294:5993-6006. [PMID: 30770472 DOI: 10.1074/jbc.ra118.006004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 02/09/2019] [Indexed: 12/22/2022] Open
Abstract
Genome replication and virion assembly of segmented RNA viruses are highly coordinated events, tightly regulated by sequence and structural elements in the UTRs of viral RNA. This process is poorly defined and likely requires the participation of host proteins in concert with viral proteins. In this study, we employed a proteomics-based approach, named RNA-protein interaction detection (RaPID), to comprehensively screen for host proteins that bind to a conserved motif within the rotavirus (RV) 3' terminus. Using this assay, we identified ATP5B, a core subunit of the mitochondrial ATP synthase, as having high affinity to the RV 3'UTR consensus sequences. During RV infection, ATP5B bound to the RV 3'UTR and co-localized with viral RNA and viroplasm. Functionally, siRNA-mediated genetic depletion of ATP5B or other ATP synthase subunits such as ATP5A1 and ATP5O reduced the production of infectious viral progeny without significant alteration of intracellular viral RNA levels or RNA translation. Chemical inhibition of ATP synthase diminished RV yield in both conventional cell culture and in human intestinal enteroids, indicating that ATP5B positively regulates late-stage RV maturation in primary intestinal epithelial cells. Collectively, our results shed light on the role of host proteins in RV genome assembly and particle formation and identify ATP5B as a novel pro-RV RNA-binding protein, contributing to our understanding of how host ATP synthases may galvanize virus growth and pathogenesis.
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Affiliation(s)
- Lili Ren
- From the Department of Medicine, Division of Gastroenterology and Hepatology, Stanford, California 94305; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305; the Palo Alto Veterans Institute of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304; the School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, China
| | - Siyuan Ding
- From the Department of Medicine, Division of Gastroenterology and Hepatology, Stanford, California 94305; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305; the Palo Alto Veterans Institute of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304.
| | - Yanhua Song
- From the Department of Medicine, Division of Gastroenterology and Hepatology, Stanford, California 94305; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305; the Palo Alto Veterans Institute of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304; the Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
| | - Bin Li
- From the Department of Medicine, Division of Gastroenterology and Hepatology, Stanford, California 94305; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305; the Palo Alto Veterans Institute of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304; the Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
| | - Muthukumar Ramanathan
- the Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California 94305
| | - Julia Co
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305
| | - Manuel R Amieva
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305
| | - Paul A Khavari
- the Palo Alto Veterans Institute of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304; the Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California 94305
| | - Harry B Greenberg
- From the Department of Medicine, Division of Gastroenterology and Hepatology, Stanford, California 94305; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305; the Palo Alto Veterans Institute of Research, Veterans Affairs Palo Alto Health Care System, Palo Alto, California 94304.
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3
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Govindarajan M. Amphiphilic glycoconjugates as potential anti-cancer chemotherapeutics. Eur J Med Chem 2017; 143:1208-1253. [PMID: 29126728 DOI: 10.1016/j.ejmech.2017.10.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 09/14/2017] [Accepted: 10/08/2017] [Indexed: 12/13/2022]
Abstract
Amphiphilicity is one of the desirable features in the process of drug development which improves the biological as well as the pharmacokinetics profile of bioactive molecule. Carbohydrate moieties present in anti-cancer natural products and synthetic molecules influence the amphiphilicity and hence their bioactivity. This review focuses on natural and synthetic amphiphilic anti-cancer glycoconjugates. Different classes of molecules with varying degree of amphiphilicity are covered with discussions on their structure-activity relationship and mechanism of action.
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Affiliation(s)
- Mugunthan Govindarajan
- Emory Institute for Drug Development, Emory University, 954 Gatewood Road, Atlanta, GA 30329, United States.
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4
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Abstract
The application of small molecules as catalysts for the diversification of natural product scaffolds is reviewed. Specifically, principles that relate to the selectivity challenges intrinsic to complex molecular scaffolds are summarized. The synthesis of analogues of natural products by this approach is then described as a quintessential "late-stage functionalization" exercise wherein natural products serve as the lead scaffolds. Given the historical application of enzymatic catalysts to the site-selective alteration of complex molecules, the focus of this Review is on the recent studies of nonenzymatic catalysts. Reactions involving hydroxyl group derivatization with a variety of electrophilic reagents are discussed. C-H bond functionalizations that lead to oxidations, aminations, and halogenations are also presented. Several examples of site-selective olefin functionalizations and C-C bond formations are also included. Numerous classes of natural products have been subjected to these studies of site-selective alteration including polyketides, glycopeptides, terpenoids, macrolides, alkaloids, carbohydrates, and others. What emerges is a platform for chemical remodeling of naturally occurring scaffolds that targets virtually all known chemical functionalities and microenvironments. However, challenges for the design of very broad classes of catalysts, with even broader selectivity demands (e.g., stereoselectivity, functional group selectivity, and site-selectivity) persist. Yet, a significant spectrum of powerful, catalytic alterations of complex natural products now exists such that expansion of scope seems inevitable. Several instances of biological activity assays of remodeled natural product derivatives are also presented. These reports may foreshadow further interdisciplinary impacts for catalytic remodeling of natural products, including contributions to SAR development, mode of action studies, and eventually medicinal chemistry.
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Affiliation(s)
- Christopher R. Shugrue
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Scott J. Miller
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
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5
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The use of fluorescently-tagged apoptolidins in cellular uptake and response studies. J Antibiot (Tokyo) 2016; 69:327-30. [PMID: 26956792 DOI: 10.1038/ja.2016.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Revised: 01/25/2016] [Accepted: 02/01/2016] [Indexed: 11/08/2022]
Abstract
The apoptolidins are glycomacrolide microbial metabolites reported to be selectively cytotoxic against tumor cells. Using fluorescently tagged active derivatives we demonstrate selective uptake of these four tagged glycomacrolides in cancer cells over healthy human blood cells. We also demonstrate the utility of these five fluorescently tagged glycomacrolides in fluorescent flow cytometry to monitor cellular uptake of the six glycomacrolides and cellular response.
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6
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Akakabe M, Kumagai K, Tsuda M, Konishi Y, Tominaga A, Kaneno D, Fukushi E, Kawabata J, Masuda A, Tsuda M. Iriomoteolides-10a and 12a, Cytotoxic Macrolides from Marine Dinoflagellate Amphidinium Species. Chem Pharm Bull (Tokyo) 2016; 64:1019-23. [DOI: 10.1248/cpb.c16-00026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | | | | | | | - Akira Tominaga
- Graduate School of Kuroshio Science and Kochi Medical School, Kochi University
| | | | | | | | | | - Masashi Tsuda
- Center for Advanced Marine Core Research, Kochi University
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7
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Giuliano MW, Miller SJ. Site-Selective Reactions with Peptide-Based Catalysts. SITE-SELECTIVE CATALYSIS 2015; 372:157-201. [DOI: 10.1007/128_2015_653] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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8
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DeGuire SM, Earl DC, Du Y, Crews BA, Jacobs AT, Ustione A, Daniel C, Chong KM, Marnett LJ, Piston DW, Bachmann BO, Sulikowski GA. Fluorescent Probes of the Apoptolidins and their Utility in Cellular Localization Studies. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201408906] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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9
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DeGuire SM, Earl DC, Du Y, Crews BA, Jacobs AT, Ustione A, Daniel C, Chong KM, Marnett LJ, Piston DW, Bachmann BO, Sulikowski GA. Fluorescent probes of the apoptolidins and their utility in cellular localization studies. Angew Chem Int Ed Engl 2014; 54:961-4. [PMID: 25430909 DOI: 10.1002/anie.201408906] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 10/27/2014] [Indexed: 11/05/2022]
Abstract
Apoptolidin A has been described among the top 0.1% most-cell-selective cytotoxic agents to be evaluated in the NCI 60 cell line panel. The molecular structure of apoptolidin A consists of a 20-membered macrolide with mono- and disaccharide moieties. In contrast to apoptolidin A, the aglycone (apoptolidinone) shows no cytotoxicity (>10 μM) when evaluated against several tumor cell lines. Apoptolidin H, the C27 deglycosylated analogue of apoptolidin A, displayed sub-micromolar activity against H292 lung carcinoma cells. Selective esterification of apoptolidins A and H with 5-azidopentanoic acid afforded azido-functionalized derivatives of potency equal to that of the parent macrolide. They also underwent strain-promoted alkyne-azido cycloaddition reactions to provide access to fluorescent and biotin-functionalized probes. Microscopy studies demonstrate apoptolidins A and H localize in the mitochondria of H292 human lung carcinoma cells.
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Affiliation(s)
- Sean M DeGuire
- Department of Chemistry, Vanderbilt University, Vanderbilt Institute of Chemical Biology, Nashville, TN 37232 (USA)
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10
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Affiliation(s)
- Alina Borovika
- a Department of Chemistry , University of Michigan , Ann Arbor , MI , 48109 , USA
| | - Pavel Nagorny
- a Department of Chemistry , University of Michigan , Ann Arbor , MI , 48109 , USA
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11
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Binary fluorous tagging enables the synthesis and separation of a 16-stereoisomer library of macrosphelides. Nat Chem 2012; 4:124-9. [PMID: 22270645 PMCID: PMC3269761 DOI: 10.1038/nchem.1233] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 11/21/2011] [Indexed: 11/08/2022]
Abstract
Fluorous mixture synthesis minimizes the effort to synthesize small-molecule libraries by labelling the molecules rather than the reaction vessels. Reactants are labelled with fluorinated tags and products can later be demixed based on the fluorine content. A limit in the number of available tags can be overcome by using binary encoding so that a total of four tags can label uniquely a library of 16 compounds. This strategy, however, means that separation based on fluorine content alone is not possible. Here, we solve this problem by selectively removing one tag after an initial demixing step; a second demixing provides each individual compound. The usefulness of this strategy is demonstrated by the synthesis of a library that contains all 16 diastereomers of the natural products macrosphelides A and E. Macrosphelide D was not in this library, and so its assigned structure was incorrect. We determined its constitution by using NMR spectroscopy and its configuration by synthesizing four candidate stereoisomers.
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12
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Du Y, Derewacz DK, Deguire SM, Teske J, Ravel J, Sulikowski GA, Bachmann BO. Biosynthesis of the Apoptolidins in Nocardiopsis sp. FU 40. Tetrahedron 2011; 67:6568-6575. [PMID: 21869849 PMCID: PMC3159176 DOI: 10.1016/j.tet.2011.05.106] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The apoptolidins are 20/21-membered macrolides produced by Nocardiopsis sp. FU40. Several members of this family are potent and remarkably selective inducers of apoptosis in cancer cell lines, likely via a distinct mitochondria associated target. To investigate the biosynthesis of this natural product, the complete genome of the apoptolidin producer Nocardiopsis sp. FU40 was sequenced and a 116 Kb region was identified containing a putative apoptolidin biosynthetic gene cluster. The apoptolidin gene cluster comprises a type I polyketide synthase, with 13 homologating modules, apparently initiated in an unprecedented fashion via transfer from a methoxymalonyl-acyl carrier protein loading module. Spanning approximately 39 open reading frames, the gene cluster was cloned into a series of overlapping cosmids and functionally validated by targeted gene disruption experiments in the producing organism. Disruption of putative PKS and P(450) genes delineated the roles of these genes in apoptolidin biosynthesis and chemical complementation studies demonstrated intact biosynthesis peripheral to the disrupted genes. This work provides insight into details of the biosynthesis of this biologically significant natural product and provides a basis for future mutasynthetic methods for the generation of non-natural apopotolidins.
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Affiliation(s)
- Yu Du
- Departments of Chemistry and Biochemistry, Institute of Chemical Biology, Vanderbilt University, Nashville, TN 77842-3012, U.S.A
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13
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Srinivasarao M, Kim Y, Li XH, Robbins DW, Fuchs PL. Studies on the Synthesis of Apoptolidin: Synthesis of a C1–C27 Fragment of Apoptolidin D. J Org Chem 2011; 76:7834-41. [PMID: 21827193 DOI: 10.1021/jo200934w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Madduri Srinivasarao
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Youngsoon Kim
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Xiaojin Harry Li
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Daniel W. Robbins
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Philip L. Fuchs
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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14
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Bachmann BO, McNees R, Melancon BJ, Ghidu VP, Clark R, Crews BC, Deguire SM, Marnett LJ, Sulikowski GA. Light-induced isomerization of apoptolidin a leads to inversion of C2-C3 double bond geometry. Org Lett 2010; 12:2944-7. [PMID: 20515014 DOI: 10.1021/ol1009398] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The isolation, characterization, and cytotoxicity against H292 cells of apoptolidin G are reported. Apoptolidin G is shown to be derived by a light-induced isomerization of the C2-C3 carbon-carbon double bond of apoptolidin A.
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Affiliation(s)
- Brian O Bachmann
- Department of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 77842-3012, USA.
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15
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Wender PA, Longcore KE. Apoptolidins E and F, new glycosylated macrolactones isolated from Nocardiopsis sp. Org Lett 2010; 11:5474-7. [PMID: 19943700 DOI: 10.1021/ol902308v] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two new glycosylated macrolactones, apoptolidins E (5) and F (6), were isolated from fermentation of the actinomycete Nocardiopsis sp. and their structures assigned. Lacking the C16 and C20 oxygens of apoptolidin A (1), these macrolides are also the first members of this family to display a 4-O-methyl-l-rhamnose at C9 rather than a 6-deoxy-4-O-methyl-l-glucose.
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Affiliation(s)
- Paul A Wender
- Department of Chemistry and Department of Chemical and Systems Biology, Stanford University, Stanford, California 94305-5080, USA.
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16
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Lewis CA, Longcore KE, Miller SJ, Wender PA. An approach to the site-selective diversification of apoptolidin A with peptide-based catalysts. JOURNAL OF NATURAL PRODUCTS 2009; 72:1864-1869. [PMID: 19769383 PMCID: PMC2857549 DOI: 10.1021/np9004932] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report the application of peptide-based catalysts to the site-selective modification of apoptolidin A (1), an agent that displays remarkable selectivity for inducing apoptosis in E1A-transformed cell lines. Key to the approach was the development of an assay suitable for the screening of dozens of catalysts in parallel reactions that could be conducted using only microgram quantities of the starting material. Employing this assay, catalysts (e.g., 11 and ent-11) were identified that afforded unique product distributions, distinct from the product mixtures produced when a simple catalyst (N,N-dimethyl-4-aminopyridine (10)) was employed. Preparative reactions were then carried out with the preferred catalysts so that unique, homogeneous apoptolidin analogues could be isolated and characterized. From these studies, three new apoptolidin analogues were obtained (12-14), each differing from the other in either the location of acyl group substituents or the number of acetate groups appended to the natural product scaffold. Biological evaluation of the new apoptolidin analogues was then conducted using growth inhibition assays based on the H292 human lung carcinoma cell line. The new analogues exhibited activities comparable to apoptolidin A.
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Affiliation(s)
- Chad A. Lewis
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107
| | - Kate E. Longcore
- Department of Chemistry and Department of Chemical and Systems Biology, Stanford University, Stanford, California, 94305-5080
| | - Scott J. Miller
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520-8107
| | - Paul A. Wender
- Department of Chemistry and Department of Chemical and Systems Biology, Stanford University, Stanford, California, 94305-5080
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17
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Ghidu VP, Ntai I, Wang J, Jacobs AT, Marnett LJ, Bachmann BO, Sulikowski GA. Combined chemical and biosynthetic route to access a new apoptolidin congener. Org Lett 2009; 11:3032-4. [PMID: 19552384 DOI: 10.1021/ol901045v] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Glycosylation of a synthetic aglycone using precursor-directed biosynthesis is facilitated by a chemical ketosynthase "knockdown" of the apoptolidin producer Nocardiopsis sp. This synthetic approach facilitated the preparation of an unnatural disaccharide derivative of apoptolidin D that substantially restores cytotoxicity against H292 cells and deconvolutes the role of the decorating sugars in apoptolidin bioactivity.
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Affiliation(s)
- Victor P Ghidu
- Department of Chemistry, Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, USA
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18
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Ghidu VP, Wang J, Wu B, Liu Q, Jacobs A, Marnett LJ, Sulikowski GA. Synthesis and evaluation of the cytotoxicity of apoptolidinones A and D. J Org Chem 2008; 73:4949-55. [PMID: 18543990 PMCID: PMC2572754 DOI: 10.1021/jo800545r] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Indexed: 11/28/2022]
Abstract
Apoptolidins A-D are microbial secondary metabolites shown to be selectively cytotoxic against several cancer cell lines and noncytotoxic against normal cells. Total syntheses of apoptolidinones A and D are reported. The efficient synthetic strategy leading to the apoptolidinones features construction of the common 20-membered macrolactone by an intramolecular Suzuki reaction and stereocontrolled aldol reactions establishing the C19/C20 and C22/C23 stereocenters. In contrast to apoptolidin A, the aglycones apoptolidinone A and D were shown to be noncytotoxic when evaluated against human lung cancer cells (H292).
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Affiliation(s)
- Victor P Ghidu
- Department of Chemistry, Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235-1822, USA
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19
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Abstract
At low temperature and in the presence of an acid catalyst, SO2 adds to 1,3-dienes equilibrating with the corresponding 3,6-dihydro-1,2-oxathiin-2-oxides (sultines). These compounds are unstable above -60 °C and equilibrate with the more stable 2,5-dihydrothiophene 1,1-dioxides (sulfolenes). The hetero-Diels-Alder additions of SO2 are suprafacial and follow the Alder endo rule. The sultines derived from 1-oxy-substituted and 1,3-dioxy-disubstituted 1,3-dienes cannot be observed at -100 °C but are believed to be formed faster than the corresponding sulfolenes. In the presence of acid catalysts, the 6-oxy-substituted sultines equilibrate with zwitterionic species that react with electron-rich alkenes such as enoxysilanes and allylsilanes, generating β,γ-unsaturated silyl sulfinates that can be desilylated and desulfinylated to generate polypropionate fragments containing up to three contiguous stereogenic centers and an (E)-alkene unit. Alternatively, the silyl sulfinates can be reacted with electrophiles to generate polyfunctional sulfones (one-pot, four-component synthesis of sulfones), or oxidized into sulfonyl chlorides and reacted with amines, then realizing a one-pot, four-component synthesis of polyfunctional sulfonamides. Using enantiomerically enriched dienes such as 1-[(R)- or 1-(S)-phenylethyloxy]-2-methyl-(E,E)-penta-1,3-dien-3-yl isobutyrate, derived from inexpensive (R)- or (S)-1-phenylethanol, enantiomerically enriched stereotriads are obtained in one-pot operations. The latter are ready for further chain elongation. This has permitted the development of expeditious total asymmetric syntheses of important natural products of biological interest such as the baconipyrones, rifamycin S, and apoptolidin A.
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20
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Craita C, Didier C, Vogel P. Short synthesis of the C16-C28 polyketide fragment of apoptolidin A aglycone. Chem Commun (Camb) 2007:2411-3. [PMID: 17844763 DOI: 10.1039/b701293d] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Starting from (E,E)-1-[(1R)-(phenylethyl)oxy]-2-methylpenta-1,3-diene and triethylsilyl enol ether of butanone rapid access to Koert's advanced C10-C28 polyketide fragment of apoptolidin A is now possible.
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Affiliation(s)
- Cotinica Craita
- Institute of Pharmaceutical Sciences, ETH Zürich, Wolfgang-Pauli-Strasse 10, CH, 8093 Zürich, Switzerland
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21
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Wehlan H, Dauber M, Fernaud MTM, Schuppan J, Keiper S, Mahrwald R, Garcia MEJ, Koert U. Apoptolidin A: total synthesis and partially glycosylated analogues. Chemistry 2007; 12:7378-97. [PMID: 16865757 DOI: 10.1002/chem.200600462] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The total synthesis of apoptolidin A is described employing an early glycosylation strategy. Strategic disconnections were chosen between C11-C12 (cross-coupling) and C19O-C1 (macrocyclization). The cis-selective glycosylation at C9-OH was achieved with the new SIBA protective group at O2/O3 of the L-glucose residue. Auxiliary substitutents at the 2-position of the 2-deoxy sugars were applied to form selectively the glycosidic linkages of the C27 disaccharide. The cross-coupling of the glycosylated northern half with the glycosylated southern half was achieved with CuI-thiophene carboxylate. The macrocyclization of a trihydroxy carboxylic acid produced the 20-membered macrolide selectively. H2SiF6 was suitable for the final deprotection of the silyl ethers and the conversion of the C21 methylketal into the hemiketal. The synthetic flexibility of the approach was proven by the synthesis of some glycovariants.
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Affiliation(s)
- Hermut Wehlan
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35032 Marburg, Germany
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22
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Jung WH, Harrison C, Shin Y, Fournier JH, Balachandran R, Raccor BS, Sikorski RP, Vogt A, Curran DP, Day BW. Total synthesis and biological evaluation of C16 analogs of (-)-dictyostatin. J Med Chem 2007; 50:2951-66. [PMID: 17542572 DOI: 10.1021/jm061385k] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structure-activity relationship of the crucial C16 region of (-)-dictyostatin was established through total synthesis of analogs followed by detailed biological characterization. A versatile synthetic strategy was used to prepare milligram quantities of 16-normethyldictyostatin, 16-epi-dictyostatin, and the C16-normethyl-C15Z isomer. Along the way, a number of other E/Z isomers and epimers were prepared, and a novel lactone ring contraction to make iso-dictyostatins with 20-membered macrolactones (instead of 22-membered macrolactones) was discovered. The synthesis of 16-normethyl-15,16-dehydrodictyostatin is the first of any dictyostatin by a maximally convergent route in which three main fragments are assembled, coupled in back-to-back steps, and then processed through refunctionalization and macrolactonization. Cell-based and biochemical evaluations showed 16-normethyl-15,16-dehydrodictyostatin and 16-normethyldictyostatin to be the most potent of the new agents, only 2- and 5-fold less active than (-)-dictyostatin itself. This data and that from previously generated dictyostatin analogs are combined to produce a picture of the structure-activity relationships in this series of anticancer agents.
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Affiliation(s)
- Won-Hyuk Jung
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA
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23
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Kim Y, Fuchs PL. Lactol-directed osmylation. Stereodivergent synthesis of four C-19,20 apoptolidin diols from a single allylic hemiacetal. Org Lett 2007; 9:2445-8. [PMID: 17539652 DOI: 10.1021/ol0707564] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A synthetic approach to prepare four Apoptolidin C-19,20 diastereomeric diol derivatives was developed. Two diastereomers were obtained from the (Z)-form, which is converted to the (E)-form, followed by dihydroxylation to deliver two more diastereomers. The (E)-allylic hemiacetal and methoxyacetal showed opposite diastereoselectivity.
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Affiliation(s)
- Youngsoon Kim
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
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24
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Wender PA, Longcore KE. Isolation, structure determination, and anti-cancer activity of apoptolidin D. Org Lett 2007; 9:691-4. [PMID: 17286376 DOI: 10.1021/ol0630245] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The isolation, characterization, and preliminary biological activity of apoptolidin D, a new apoptolidin that exhibits anti-proliferative activity against H292 human lung carcinoma cells at nanomolar concentrations, are reported. Its equilibration with isoapoptolidin D and characterization of the latter are also described. [structure: see text].
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Affiliation(s)
- Paul A Wender
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
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25
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Schuppan J, Wehlan H, Keiper S, Koert U. Apoptolidinone A: Synthesis of the Apoptolidin A Aglycone. Chemistry 2006; 12:7364-77. [PMID: 16865756 DOI: 10.1002/chem.200600461] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An efficient stereocontrolled synthesis of apoptolidinone A, the aglycone of apoptolidin A is described. The synthetic strategy relies on a cross coupling between C11/C12 of a northern half (C1-C11) and a southern part (C12-C28) followed by a ring-size selective macrolactonization. Key steps for the introduction of the southern half stereocenters are a stereoselective aldol reaction, a substrate controlled dihydroxylation and a chelation-controlled Grignard/aldehyde addition. The conjugated triene of the northern half was built up successively by E-selective Wittig reactions. L-Malic acid was chosen as the chiral pool source for the C8/C9 stereocenters. The final cleavage of the silyl ethers and the conversion of the C21 methyl ketal into the hemiketal was achieved by HF.pyridine.
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Affiliation(s)
- Julia Schuppan
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35032 Marburg, Germany
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26
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Wender PA, Sukopp M, Longcore K. Apoptolidins B and C: isolation, structure determination, and biological activity. Org Lett 2006; 7:3025-8. [PMID: 15987196 PMCID: PMC2533581 DOI: 10.1021/ol051074o] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Apoptolidin (1) is a promising new therapeutic lead that exhibits remarkable selectivity against cancer cells relative to normal cells. We report the isolation, characterization, solution structure, stability, and biological activity of two new members of this family: apoptolidins B (2) and C (3). These new agents are found to have antiproliferative activity on par with or better than apoptolidin itself in an assay with H292 lung cancer cells.
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Affiliation(s)
- Paul A Wender
- Department of Chemistry, Stanford University, California 94305-5080, USA.
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27
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Wender PA, Jankowski OD, Longcore K, Tabet EA, Seto H, Tomikawa T. Correlation of F0F1-ATPase inhibition and antiproliferative activity of apoptolidin analogues. Org Lett 2006; 8:589-92. [PMID: 16468718 PMCID: PMC2533578 DOI: 10.1021/ol052800q] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[structure: see text] Apoptolidin (1) exhibits potent and highly selective apoptosis inducing activity against sensitive cancer cell lines and is hypothesized to act by inhibition of mitochondrial F(0)F(1)-ATP synthase. A series of apoptolidin derivatives, including a new intermolecular Diels-Alder adduct, were analyzed for antiproliferative activity in E1A-transformed rat fibroblasts. Potent F(0)F(1)-ATPase inhibition was not a sufficient determinant of antiproliferative activity for several analogues, suggesting the existence of a secondary biological target or more complex mode of action for apoptolidin.
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Affiliation(s)
- Paul A Wender
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
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28
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Daniel PT, Koert U, Schuppan J. Apoptolidin: Induction of Apoptosis by a Natural Product. Angew Chem Int Ed Engl 2006; 45:872-93. [PMID: 16404760 DOI: 10.1002/anie.200502698] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Apoptolidin is a natural product that selectively induces apoptosis in several cancer cell lines. Apoptosis, programmed cell death, is a biological key pathway for regulating homeostasis and morphogenesis. Apoptotic misregulations are connected with several diseases, in particular cancer. The extrinsic way to apoptosis leads through death ligands and death receptors to the activiation of the caspase cascade, which results in proteolytic degradation of the cell architecture. The intrinsic pathway transmits signals of internal cellular damage to the mitochondrion, which loses its structural integrity, and forms an apoptosome that initiates the caspase cascade. Compounds which regulate apoptosis are of high medical significance. Many natural products regulate apoptotic pathways, and apoptolidin is one of them. The known synthetic routes to apoptolidin are described and compared in this Review. Selected further natural products which regulate apoptosis are introduced briefly.
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Affiliation(s)
- Peter T Daniel
- Department of Hematology, Oncology and Tumor Immunology, University Medical Center Charité, Humboldt University of Berlin, Germany
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29
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Daniel PT, Koert U, Schuppan J. Apoptolidin: Induktion von Apoptose durch einen Naturstoff. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200502698] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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30
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Wu B, Liu Q, Jin B, Qu T, Sulikowski GA. Studies on the Synthesis of Apoptolidin: Progress on the Stereocontrolled Assembly of the Pseudo Aglycone of Apoptolidin. European J Org Chem 2006. [DOI: 10.1002/ejoc.200500632] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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31
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Crimmins MT, Christie HS, Chaudhary K, Long A. Enantioselective Synthesis of Apoptolidinone: Exploiting the Versatility of Thiazolidinethione Chiral Auxiliaries. J Am Chem Soc 2005; 127:13810-2. [PMID: 16201800 DOI: 10.1021/ja0549289] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An efficient, enantioselective synthesis of apoptolidinone has been completed, demonstrating the versatility of thiazolidinethione auxiliaries. Three propionate aldol additions and two asymmetric glycolate alkylations function to establish 8 of the 12 stereogenic carbon centers. A cross-metathesis reaction is utilized to assemble the C1-C10 trieneoate fragment and the C11-C28 polypropionate region of the molecule.
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Affiliation(s)
- Michael T Crimmins
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
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32
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Abstract
[structure: see text] The de novo synthesis of the C9 and C27 sugar subunits (2) and (3), respectively, of the potent antitumor agent, apoptolidin, has been accomplished. A titanium tetrachloride-mediated asymmetric anti glycolate aldol addition was utilized to establish the 4' and 5' stereogenic centers of each of the three monosaccharides. Elaboration of the aldol adducts efficiently provided the three sugar units. A beta-selective glycosidation completed the construction of the C27 disaccharide.
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Affiliation(s)
- Michael T Crimmins
- Venable and Kenan Laboratories of Chemistry, Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
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33
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Development of an end-game strategy towards apoptolidin: a sequential Suzuki coupling approach. Tetrahedron 2005. [DOI: 10.1016/j.tet.2004.10.088] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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34
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35
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Affiliation(s)
- Bin Wu
- Department of Chemistry, Vanderbilt University, 7920 Stevenson Center, Nashville, TN 37235, USA
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36
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Abe K, Kato K, Arai T, Rahim MA, Sultana I, Matsumura S, Toshima K. Synthetic studies on apoptolidin: synthesis of the C12–C28 fragment via a highly stereoselective aldol reaction. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.09.177] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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37
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Nicolaou KC, Li Y, Sugita K, Monenschein H, Guntupalli P, Mitchell HJ, Fylaktakidou KC, Vourloumis D, Giannakakou P, O'Brate A. Total Synthesis of Apoptolidin: Completion of the Synthesis and Analogue Synthesis and Evaluation. J Am Chem Soc 2003; 125:15443-54. [PMID: 14664590 DOI: 10.1021/ja030496v] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The total synthesis of apoptolidin (1) is reported together with the design, synthesis, and biological evaluation of a number of analogues. The assembly of key fragments 6 and 7 to vinyl iodide 3 via dithiane coupling technology was supplemented by a second generation route to this advanced intermediate involving a Horner-Wadsworth-Emmons coupling of fragments 22 and 25. The final stages of the synthesis featured a Stille coupling between vinyl iodide 3 and vinylstannane 2, a Yamaguchi lactonization, a number of glycosidations, and final deprotection. The developed synthetic technology was applied to the construction of several analogues including 74, 75, and 77 which exhibit significant bioactivity against tumor cells.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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38
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Wender PA, Jankowski OD, Tabet EA, Seto H. Facile synthetic access to and biological evaluation of the macrocyclic core of apoptolidin. Org Lett 2003; 5:2299-302. [PMID: 12816433 DOI: 10.1021/ol0346335] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxidative cleavage of the C-20/C-21 bond in apoptolidin (1) provides two fragments of similar complexity, facilitating a divide-and-diversify strategy for the determination of the structural basis for apoptolidin's biological activity, the remarkably selective induction of apoptosis in sensitive cell lines. The ability of compounds derived from this cleavage to inhibit mitochondrial F(0)F(1)-ATPase is reported. [structure: see text]
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Affiliation(s)
- Paul A Wender
- Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA.
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39
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Wender PA, Jankowski OD, Tabet EA, Seto H. Toward a structure-activity relationship for apoptolidin: selective functionalization of the hydroxyl group array. Org Lett 2003; 5:487-90. [PMID: 12583750 DOI: 10.1021/ol027366w] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] To investigate the structural basis for the exceptional selectivity and activity of apoptolidin (1), a strategy has been devised that allows for selective functionalization of seven of its eight hydroxyl groups based on progressive silyl protection, derivatization, and deprotection. The syntheses of these derivatives and their ability to inhibit F(0)F(1)-ATPase are reported.
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Affiliation(s)
- Paul A Wender
- Department of Chemistry, Stanford University, Stanford, California, 94305-5080, USA.
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