1
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Weber F, Weber A, Schmitt L, Lechtenberg I, Greb J, Henßen B, Wesselborg S, Pietruszka J. From the Total Synthesis of Semi-Viriditoxin, Semi-Viriditoxic Acid and Dimeric Naphthopyranones to their Biological Activities in Burkitt B Cell Lymphoma. Chemistry 2024; 30:e202400559. [PMID: 38411573 DOI: 10.1002/chem.202400559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 02/26/2024] [Accepted: 02/27/2024] [Indexed: 02/28/2024]
Abstract
Dimeric naphthopyranones are known to be biologically active, however, for the corresponding monomeric naphthopyranones this information is still elusive. Here the first enantioselective total synthesis of semi-viriditoxic acid as well as the synthesis of semi-viriditoxin and derivatives is reported. The key intermediate in the synthesis of naphthopyranones is an α,β-unsaturated δ-lactone, which we synthesized in two different ways (Ghosez-cyclization and Grubbs ring-closing metathesis), while the domino-Michael-Dieckmann reaction of the α,β-unsaturated δ-lactone with an orsellinic acid derivative is the key reaction. A structure-activity relationship study was performed measuring the cytotoxicity in Burkitt B lymphoma cells (Ramos). The dimeric structure was found to be crucial for biological activity: Only the dimeric naphthopyranones showed cytotoxic and apoptotic activity, whereas the monomers did not display any activity at all.
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Affiliation(s)
- Frederike Weber
- Institute for Bioorganic Chemistry, Heinrich Heine University Düsseldorf in, Forschungszentrum Jülich, 52426, Jülich, Germany
| | - Anja Weber
- Institute for Bioorganic Chemistry, Heinrich Heine University Düsseldorf in, Forschungszentrum Jülich, 52426, Jülich, Germany
| | - Laura Schmitt
- Institute for Molecular Medicine I, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Ilka Lechtenberg
- Institute for Molecular Medicine I, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Julian Greb
- Institute for Bioorganic Chemistry, Heinrich Heine University Düsseldorf in, Forschungszentrum Jülich, 52426, Jülich, Germany
| | - Birgit Henßen
- Institute for Bioorganic Chemistry, Heinrich Heine University Düsseldorf in, Forschungszentrum Jülich, 52426, Jülich, Germany
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich, 52426, Jülich, Germany
| | - Sebastian Wesselborg
- Institute for Molecular Medicine I, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Jörg Pietruszka
- Institute for Bioorganic Chemistry, Heinrich Heine University Düsseldorf in, Forschungszentrum Jülich, 52426, Jülich, Germany
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich, 52426, Jülich, Germany
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2
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Moreno González A, Nicholson K, Llopis N, Nichol GS, Langer T, Baeza A, Thomas SP. Diastereoselective, Catalytic Access to Cross-Aldol Products Directly from Esters and Lactones. Angew Chem Int Ed Engl 2022; 61:e202209584. [PMID: 35916601 PMCID: PMC9804986 DOI: 10.1002/anie.202209584] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Indexed: 01/09/2023]
Abstract
High oxidation-state carbonyl coupling partners including esters and lactones were reacted with enones to give aldol-type products directly using two-fold organoborane catalysis. This new retrosynthetic disconnection to aldol-type products is compatible with enolisable coupling partners, without self-condensation, and couples the high reactivity of secondary dialkylboranes with the stability of pinacolboronic esters. Excellent chemoselectivity, substrate scope (including those containing reducible functionalities and free alcohols) and diastereocontrol were achieved to access both the syn- and anti-aldol-type products. Mechanistic studies confirmed the two-fold catalytic role of the single secondary borane catalyst for boron enolate formation and formation of an aldehyde surrogate from the ester or lactone coupling partner.
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Affiliation(s)
- Adrián Moreno González
- EaStCHEM School of ChemistryUniversity of EdinburghDavid Brewster RoadEdinburghEH9 3FJUK
| | - Kieran Nicholson
- EaStCHEM School of ChemistryUniversity of EdinburghDavid Brewster RoadEdinburghEH9 3FJUK
| | - Natalia Llopis
- EaStCHEM School of ChemistryUniversity of EdinburghDavid Brewster RoadEdinburghEH9 3FJUK
| | - Gary S. Nichol
- EaStCHEM School of ChemistryUniversity of EdinburghDavid Brewster RoadEdinburghEH9 3FJUK
| | - Thomas Langer
- AstraZeneca Pharmaceutical Technology & DevelopmentChemical Development UKSilk RoadMacclesfieldSK10 2NAUK
| | - Alejandro Baeza
- Instituto de Síntesis Orgánica and Dpto. de Química OrgánicaUniversidad de AlicanteApdo. 9903080AlicanteSpain
| | - Stephen P. Thomas
- EaStCHEM School of ChemistryUniversity of EdinburghDavid Brewster RoadEdinburghEH9 3FJUK
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3
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Thomas S, González AM, Nicholson K, Llopis N, Nichol GS, Langer T, Baeza A. Diastereoselective, Catalytic Access to Cross‐aldol Products Directly from Esters and Lactones. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202209584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Stephen Thomas
- University of Edinburgh School of Chemistry Joseph Black Building,King's Buildings, West Mains Road EH9 3FJ Edinburgh UNITED KINGDOM
| | | | - Kieran Nicholson
- The University of Edinburgh School of Chemistry School of Chemistry UNITED KINGDOM
| | - Natalia Llopis
- The University of Edinburgh School of Chemistry School of Chemistry UNITED KINGDOM
| | - Gary S. Nichol
- The University of Edinburgh School of Chemistry School of Chemistry UNITED KINGDOM
| | - Thomas Langer
- AstraZeneca UK Ltd Macclesfield Chemical Development UK UNITED KINGDOM
| | - Alejandro Baeza
- Universidad de Alicante: Universitat d'Alacant Dpto. de Química Orgánica SPAIN
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4
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Lam NYS, Stockdale TP, Anketell MJ, Paterson I. Conquering peaks and illuminating depths: developing stereocontrolled organic reactions to unlock nature's macrolide treasure trove. Chem Commun (Camb) 2021; 57:3171-3189. [PMID: 33666631 DOI: 10.1039/d1cc00442e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The structural complexity and biological importance of macrolide natural products has inspired the development of innovative strategies for their chemical synthesis. With their dense stereochemical content, high level of oxygenation and macrocyclic cores, we viewed the efficient total synthesis of these valuable compounds as an aspirational driver towards developing robust methods and strategies for their construction. Starting out from the initial development of our versatile asymmetric aldol methodology, this personal perspective reflects on an adventurous journey, with all its trials, tribulations and serendipitous discoveries, across the total synthesis, in our group, of a representative selection of six macrolide natural products of marine and terrestrial origin - swinholide A, spongistatin 1, spirastrellolide A, leiodermatolide, chivosazole F and actinoallolide A.
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Affiliation(s)
- Nelson Y S Lam
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
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5
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Reher R, Kim HW, Zhang C, Mao HH, Wang M, Nothias LF, Caraballo-Rodriguez AM, Glukhov E, Teke B, Leao T, Alexander KL, Duggan BM, Van Everbroeck EL, Dorrestein PC, Cottrell GW, Gerwick WH. A Convolutional Neural Network-Based Approach for the Rapid Annotation of Molecularly Diverse Natural Products. J Am Chem Soc 2020; 142:4114-4120. [PMID: 32045230 DOI: 10.1021/jacs.9b13786] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This report describes the first application of the novel NMR-based machine learning tool "Small Molecule Accurate Recognition Technology" (SMART 2.0) for mixture analysis and subsequent accelerated discovery and characterization of new natural products. The concept was applied to the extract of a filamentous marine cyanobacterium known to be a prolific producer of cytotoxic natural products. This environmental Symploca extract was roughly fractionated, and then prioritized and guided by cancer cell cytotoxicity, NMR-based SMART 2.0, and MS2-based molecular networking. This led to the isolation and rapid identification of a new chimeric swinholide-like macrolide, symplocolide A, as well as the annotation of swinholide A, samholides A-I, and several new derivatives. The planar structure of symplocolide A was confirmed to be a structural hybrid between swinholide A and luminaolide B by 1D/2D NMR and LC-MS2 analysis. A second example applies SMART 2.0 to the characterization of structurally novel cyclic peptides, and compares this approach to the recently appearing "atomic sort" method. This study exemplifies the revolutionary potential of combined traditional and deep learning-assisted analytical approaches to overcome longstanding challenges in natural products drug discovery.
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Affiliation(s)
- Raphael Reher
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Hyun Woo Kim
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Chen Zhang
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States.,Department of Computer Science and Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Huanru Henry Mao
- Department of Computer Science and Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Mingxun Wang
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Louis-Félix Nothias
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Andres Mauricio Caraballo-Rodriguez
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Evgenia Glukhov
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Bahar Teke
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Tiago Leao
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Kelsey L Alexander
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States.,Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Brendan M Duggan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Ezra L Van Everbroeck
- Director's Office, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Pieter C Dorrestein
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - Garrison W Cottrell
- Department of Computer Science and Engineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - William H Gerwick
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States.,Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
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6
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Doerksen RS, Meyer CC, Krische MJ. Feedstock Reagents in Metal-Catalyzed Carbonyl Reductive Coupling: Minimizing Preactivation for Efficiency in Target-Oriented Synthesis. Angew Chem Int Ed Engl 2019; 58:14055-14064. [PMID: 31162793 PMCID: PMC6764920 DOI: 10.1002/anie.201905532] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Indexed: 12/11/2022]
Abstract
Use of abundant feedstock pronucleophiles in catalytic carbonyl reductive coupling enhances efficiency in target-oriented synthesis. For such reactions, equally inexpensive reductants are desired or, ideally, corresponding hydrogen autotransfer processes may be enacted wherein alcohols serve dually as reductant and carbonyl proelectrophile. As described in this Minireview, these concepts allow reactions that traditionally require preformed organometallic reagents to be conducted catalytically in a byproduct-free manner from inexpensive π-unsaturated precursors.
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Affiliation(s)
- Rosalie S. Doerksen
- University of Texas at Austin, Department of Chemistry Welch Hall (A5300), 105 E 24 St., Austin, TX 78712, USA
| | - Cole C. Meyer
- University of Texas at Austin, Department of Chemistry Welch Hall (A5300), 105 E 24 St., Austin, TX 78712, USA
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry Welch Hall (A5300), 105 E 24 St., Austin, TX 78712, USA
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7
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Diaz-Muñoz G, Miranda IL, Sartori SK, de Rezende DC, Alves Nogueira Diaz M. Use of chiral auxiliaries in the asymmetric synthesis of biologically active compounds: A review. Chirality 2019; 31:776-812. [PMID: 31418934 DOI: 10.1002/chir.23103] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 05/13/2019] [Accepted: 05/22/2019] [Indexed: 01/16/2023]
Abstract
This review article describes the use of some of the most popular chiral auxiliaries in the asymmetric synthesis of biologically active compounds. Chiral auxiliaries derived from naturally occurring compounds, such as amino acids, carbohydrates, and terpenes, are considered essential tools for the construction of highly complex molecules. We highlight the auxiliaries of Evans, Corey, Yamada, Enders, Oppolzer, and Kunz, which led to remarkable progress in asymmetric synthesis in the last decades and continue to bring advances until the present day.
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Affiliation(s)
- Gaspar Diaz-Muñoz
- Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Izabel Luzia Miranda
- Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Suélen Karine Sartori
- Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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8
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Doerksen RS, Meyer CC, Krische MJ. Feedstock Reagents in Metal‐Catalyzed Carbonyl Reductive Coupling: Minimizing Preactivation for Efficiency in Target‐Oriented Synthesis. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201905532] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Rosalie S. Doerksen
- University of Texas at Austin Department of Chemistry 105 E 24th St. (A5300) Austin TX 78712-1167 USA
| | - Cole C. Meyer
- University of Texas at Austin Department of Chemistry 105 E 24th St. (A5300) Austin TX 78712-1167 USA
| | - Michael J. Krische
- University of Texas at Austin Department of Chemistry 105 E 24th St. (A5300) Austin TX 78712-1167 USA
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9
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Abstract
The field of natural product total synthesis has reached the point where synthetic efficiency has become more important than merely defining a viable (yet less ideal) route to the target molecule. Synthetic efficiency is best represented by the number of steps it takes to finish the target molecule from readily available starting materials, as by reducing the number of steps, all other factors of synthetic efficiency are influenced positively. By comparing several total syntheses from the recent years, the most successful strategies for step efficient syntheses will be highlighted. Each synthesis will be presented using a color-coded synthetic flowchart, in which each step is categorized by a colored box. Five categories of transformations are defined and rated according to their synthetic value. Each class will be signified by different colors so that the reader can quickly see which parts of the synthesis are productive and those that are not.
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Affiliation(s)
- Johannes Schwan
- Freie Universität Berlin, Institute of Chemistry and Biochemistry, Takustraße 3, 10781 Berlin, Germany.
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10
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Tao Y, Li P, Zhang D, Glukhov E, Gerwick L, Zhang C, Murray TF, Gerwick WH. Samholides, Swinholide-Related Metabolites from a Marine Cyanobacterium cf. Phormidium sp. J Org Chem 2018; 83:3034-3046. [PMID: 29457979 PMCID: PMC5859247 DOI: 10.1021/acs.joc.8b00028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
![]()
Cancer cell cytotoxicity was used
to guide the isolation of nine
new swinholide-related compounds, named samholides A–I (1–9), from an American Samoan marine cyanobacterium
cf. Phormidium sp. Their structures were determined
by extensive analysis of 1D and 2D NMR spectroscopic data. The new
compounds share an unusual 20-demethyl 44-membered lactone ring composed
of two monomers, and they demonstrate structural diversity arising
from geometric isomerization of double bonds, sugar units with unique
glyceryl moieties and varied methylation patterns. All of the new
samholides were potently active against the H-460 human lung cancer
cell line with IC50 values ranging from 170 to 910 nM.
The isolation of these new swinholide-related compounds from a marine
cyanobacterium reinvigorates questions concerning the evolution and
biosynthetic origin of these natural products.
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Affiliation(s)
- Yiwen Tao
- Key Laboratory of Molecular Target & Clinical Pharmacology, School of Pharmaceutical Sciences and the Fifth Affiliated Hospital , Guangzhou Medical University , Guangzhou 511436 , People's Republic of China.,Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography , University of California San Diego , La Jolla , California 92093 , United States
| | - Pinglin Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy , Ocean University of China , Qingdao 266003 , People's Republic of China.,Laboratory for Marine Drugs and Bioproducts , Qingdao National Laboratory for Marine Science and Technology , Qingdao 266235 , People's Republic of China.,Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography , University of California San Diego , La Jolla , California 92093 , United States
| | - Daojing Zhang
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography , University of California San Diego , La Jolla , California 92093 , United States.,State Key Laboratory of Bioreactor Engineering , East China University of Science & Technology , Shanghai 200237 , People's Republic of China
| | - Evgenia Glukhov
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography , University of California San Diego , La Jolla , California 92093 , United States
| | - Lena Gerwick
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography , University of California San Diego , La Jolla , California 92093 , United States
| | - Chen Zhang
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography , University of California San Diego , La Jolla , California 92093 , United States
| | - Thomas F Murray
- Department of Pharmacology , Creighton University School of Medicine , Omaha , Nebraska 68178 , United States
| | - William H Gerwick
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography , University of California San Diego , La Jolla , California 92093 , United States.,Skaggs School of Pharmacy and Pharmaceutical Sciences , University of California San Diego , La Jolla , California 92093 , United States
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11
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Abstract
An overview of the highlights in total synthesis of natural products using iridium as a catalyst is given.
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Affiliation(s)
- Changchun Yuan
- School of Chemical Engineering and Technology
- North University of China
- Taiyuan 030051
- PR China
| | - Bo Liu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education
- College of Chemistry
- Sichuan University
- Chengdu 610064
- PR China
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12
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Cui J, Morita M, Ohno O, Kimura T, Teruya T, Watanabe T, Suenaga K, Shibasaki M. Leptolyngbyolides, Cytotoxic Macrolides from the Marine Cyanobacterium Leptolyngbya sp.: Isolation, Biological Activity, and Catalytic Asymmetric Total Synthesis. Chemistry 2017; 23:8500-8509. [PMID: 28422340 DOI: 10.1002/chem.201701183] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Indexed: 12/15/2022]
Abstract
Four new macrolactones, leptolyngbyolides A-D, were isolated from the cyanobacterium Leptolyngbya sp. collected in Okinawa, Japan. The planar structures of leptolyngbyolides were determined by extensive NMR studies, although complete assignment of the absolute configuration awaited the catalytic asymmetric total synthesis of leptolyngbyolide C. The synthesis took advantage of the catalytic asymmetric thioamide-aldol reaction using copper(I) complexed with a chiral bidentate phosphine ligand to regulate two key stereochemistries of the molecule at the outset. The present total synthesis demonstrates the utility of this reaction for the construction of complex chemical entities. In addition to the total synthesis, this work reports that leptolyngbyolides depolymerize filamentous actin (F-actin) both in vitro and in cells. Detailed biological studies suggest the probable order of F-actin depolymerization and apoptosis caused by leptolyngbyolides.
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Affiliation(s)
- Jin Cui
- Institute of Microbial Chemistry (BIKAKEN), Tokyo, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo, 141-0021, Japan
| | - Maho Morita
- Department of Chemistry, Keio University, 3-14-1 Hiyoshi Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Osamu Ohno
- Department of Chemistry, Keio University, 3-14-1 Hiyoshi Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Tomoyuki Kimura
- Institute of Microbial Chemistry (BIKAKEN), Tokyo, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo, 141-0021, Japan
| | - Toshiaki Teruya
- Faculty of Education, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa, 993-0213, Japan
| | - Takumi Watanabe
- Institute of Microbial Chemistry (BIKAKEN), Tokyo, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo, 141-0021, Japan
| | - Kiyotake Suenaga
- Department of Chemistry, Keio University, 3-14-1 Hiyoshi Kohoku-ku, Yokohama, Kanagawa, 223-8522, Japan
| | - Masakatsu Shibasaki
- Institute of Microbial Chemistry (BIKAKEN), Tokyo, 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo, 141-0021, Japan
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13
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Abstract
This review defines symmetric molecules from a synthetic perspective and shows various strategies that take advantage of molecular symmetry to construct them.
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Affiliation(s)
- Wen-Ju Bai
- Department of Chemistry
- Stanford University
- Stanford
- USA
| | - Xiqing Wang
- College of Bioscience and Biotechnology
- Yangzhou University
- Yangzhou
- China
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14
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Shin I, Hong S, Krische MJ. Total Synthesis of Swinholide A: An Exposition in Hydrogen-Mediated C-C Bond Formation. J Am Chem Soc 2016; 138:14246-14249. [PMID: 27779393 PMCID: PMC5096380 DOI: 10.1021/jacs.6b10645] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Diverse hydrogen-mediated C-C couplings enable construction of the actin-binding marine polyketide swinholide A in only 15 steps (longest linear sequence), roughly half the steps required in two prior total syntheses. The redox-economy, chemo- and stereoselectivity embodied by this new class of C-C couplings are shown to evoke a step-change in efficiency.
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Affiliation(s)
- Inji Shin
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Suckchang Hong
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Michael J Krische
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
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15
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Ramírez-Contreras R, Morandi B. Chemo- and Regioselective Functionalization of Polyols through Catalytic C(sp(3))-C(sp(3)) Kumada-Type Coupling of Cyclic Sulfate Esters. Org Lett 2016; 18:3718-21. [PMID: 27441850 DOI: 10.1021/acs.orglett.6b01745] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This contribution describes a copper-catalyzed, C(sp(3))-C(sp(3)) cross-coupling reaction of cyclic sulfate esters, a distinct class of electrophilic derivatives of polyols, with alkyl Grignard reagents to afford functionalized alcohol products in good yields. The method is operationally simple and highlights the potential of cyclic sulfate esters as highly reactive substrates in catalytic, chemoselective polyol transformations.
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Affiliation(s)
| | - Bill Morandi
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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16
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Feng J, Kasun ZA, Krische MJ. Enantioselective Alcohol C-H Functionalization for Polyketide Construction: Unlocking Redox-Economy and Site-Selectivity for Ideal Chemical Synthesis. J Am Chem Soc 2016; 138:5467-78. [PMID: 27113543 PMCID: PMC4871165 DOI: 10.1021/jacs.6b02019] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The development and application of stereoselective and site-selective catalytic methods that directly convert lower alcohols to higher alcohols are described. These processes merge the characteristics of transfer hydrogenation and carbonyl addition, exploiting alcohols and π-unsaturated reactants as redox pairs, which upon hydrogen transfer generate transient carbonyl-organometal pairs en route to products of C-C coupling. Unlike classical carbonyl additions, stoichiometric organometallic reagents and discrete alcohol-to-carbonyl redox reactions are not required. Additionally, due to a kinetic preference for primary alcohol dehydrogenation, the site-selective modification of glycols and higher polyols is possible, streamlining or eliminating use of protecting groups. The total syntheses of several iconic type I polyketide natural products were undertaken using these methods. In each case, the target compounds were prepared in significantly fewer steps than previously achieved.
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Affiliation(s)
- Jiajie Feng
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Zachary A. Kasun
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
| | - Michael J. Krische
- University of Texas at Austin, Department of Chemistry, Austin, TX 78712, USA
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17
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Shin I, Krische MJ. Formal Synthesis of Premisakinolide A and C(19)-C(32) of Swinholide A via Site-Selective C-H Allylation and Crotylation of Unprotected Diols. Org Lett 2016; 17:4686-9. [PMID: 26375150 DOI: 10.1021/acs.orglett.5b02056] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Using stereo- and site-selective C-H allylation and crotylation of unprotected diols, an intermediate in the synthesis of premisakinolide A (bistheonellic acid B) that was previously made in 16-27 (LLS) steps is now prepared in only nine steps. This fragment also represents a synthesis of C(19)-C(32) of the actin-binding macrodiolide swinholide A.
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Affiliation(s)
- Inji Shin
- Department of Chemistry and Biochemistry, University of Texas at Austin , Austin, Texas 78712, United States
| | - Michael J Krische
- Department of Chemistry and Biochemistry, University of Texas at Austin , Austin, Texas 78712, United States
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McSweeney CM, Foley VM, McGlacken GP. The asymmetric alkylation of dimethylhydrazones; intermolecular chirality transfer using sparteine as chiral ligand. Chem Commun (Camb) 2015; 50:14817-9. [PMID: 25318599 DOI: 10.1039/c4cc06895e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The asymmetric alkylation of ketones represents a fundamental transformation in organic chemistry. Chiral auxiliaries have been used almost exclusively for this transformation. Herein we describe a strategy for the generation of enantiomerically enriched α-alkylated ketones up to an er of 83 : 17, using a chiral ligand protocol.
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Affiliation(s)
- Christina M McSweeney
- Analytical and Biological Chemistry Research Facility and Department of Chemistry, University College Cork, Cork, Ireland.
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20
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Ajito K, Miura T, Furuuchi T, Tamura A. Sixteen-Membered Macrolides: Chemical Modifications and Future Applications. HETEROCYCLES 2014. [DOI: 10.3987/rev-13-785] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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21
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Gerard B, Lee MD, Dandapani S, Duvall JR, Fitzgerald ME, Kesavan S, Lowe JT, Marié JC, Pandya BA, Suh BC, O'Shea MW, Dombrowski M, Hamann D, Lemercier B, Murillo T, Akella LB, Foley MA, Marcaurelle LA. Synthesis of stereochemically and skeletally diverse fused ring systems from functionalized C-glycosides. J Org Chem 2013; 78:5160-71. [PMID: 23692141 DOI: 10.1021/jo4000916] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A diversity-oriented synthesis (DOS) strategy was developed for the synthesis of stereochemically diverse fused-ring systems containing a pyran moiety. Each scaffold contains an amine and methyl ester for further diversification via amine capping and amide coupling. Scaffold diversity was evaluated in comparison to previously prepared scaffolds by a shape-based principal moments of inertia (PMI) analysis.
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Affiliation(s)
- Baudouin Gerard
- Chemical Biology Platform, The Broad Institute of Harvard and MIT, 7 Cambridge Center, Cambridge, Massachusetts 02142, United States
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22
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Gao X, Han H, Krische MJ. Direct generation of acyclic polypropionate stereopolyads via double diastereo- and enantioselective iridium-catalyzed crotylation of 1,3-diols: beyond stepwise carbonyl addition in polyketide construction. J Am Chem Soc 2011; 133:12795-800. [PMID: 21739988 DOI: 10.1021/ja204570w] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Under the conditions of transfer hydrogenation employing the cyclometalated iridium catalyst (R)-I derived from [Ir(cod)Cl](2), allyl acetate, 4-cyano-3-nitrobenzoic acid, and the chiral phosphine ligand (R)-SEGPHOS, α-methylallyl acetate engages 1,3-propanediol (1a) and 2-methyl-1,3-propanediol (1b) in double carbonyl crotylation from the alcohol oxidation level to deliver the C(2)-symmetric and pseudo-C(2)-symmetric stereopolyads 2a and 3a, respectively, with exceptional control of anti-diastereoselectivity and enantioselectivity. Notably, the polypropionate stereopentad 3a is formed predominantly as 1 of 16 possible stereoisomers. Desymmetrization of 3a is readily achieved upon iodoetherification to form pyran 4. The direct generation of 3a enables a dramatically simplified approach to previously prepared polypropionate substructures, as demonstrated by the synthesis of C19-C27 of rifamycin S (eight steps, originally prepared in 26 steps) and C19-C25 of scytophycin C (eight steps, originally prepared in 15 steps). The present transfer hydrogenation protocol represents an alternative to chiral auxiliaries, chiral reagents, and premetalated nucleophiles in polyketide construction.
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Affiliation(s)
- Xin Gao
- Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712, United States
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23
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Fragment-based domain shuffling approach for the synthesis of pyran-based macrocycles. Proc Natl Acad Sci U S A 2011; 108:6751-6. [PMID: 21383141 DOI: 10.1073/pnas.1015255108] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Complexity and the presence of stereogenic centers have been correlated with success as compounds transition from discovery through the clinic. Here we describe the synthesis of a library of pyran-containing macrocycles with a high degree of structural complexity and up to five stereogenic centers. A key feature of the design strategy was to use a modular synthetic route with three fragments that can be readily interchanged or "shuffled" to produce subtly different variants with distinct molecular shapes. A total of 352 macrocycles were synthesized ranging in size from 14- to 16-membered rings. In order to facilitate the generation of stereostructure-activity relationships, the complete matrix of stereoisomers was prepared for each macrocycle. Solid-phase assisted parallel solution-phase techniques were employed to allow for rapid analogue generation. An intramolecular nitrile-activated nucleophilic aromatic substitution reaction was used for the key macrocyclization step.
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24
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Miura T, Kanemoto K, Ajito K. Chemical Transformation of Lactone Starting from 16-Membered Macrolides, Leucomycins, and Generation of Novel Azalides. J SYN ORG CHEM JPN 2011. [DOI: 10.5059/yukigoseikyokaishi.69.1339] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kartika R, Frein JD, Taylor RE. Electrophile-Induced Ether Transfer: Stereoselective Synthesis of 2,6-Disubstituted-3,4-Dihydropyrans. J Org Chem 2008; 73:5592-4. [DOI: 10.1021/jo800704d] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rendy Kartika
- Department of Chemistry and Biochemistry and the Walther Cancer Research Center, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, Indiana 46556
| | - Jeffrey D. Frein
- Department of Chemistry and Biochemistry and the Walther Cancer Research Center, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, Indiana 46556
| | - Richard E. Taylor
- Department of Chemistry and Biochemistry and the Walther Cancer Research Center, University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, Indiana 46556
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27
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Vrettou M, Gray AA, Brewer AR, Barrett AG. Strategies for the synthesis of C2 symmetric natural products—a review. Tetrahedron 2007. [DOI: 10.1016/j.tet.2006.09.109] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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28
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Nicolaou KC, Snyder SA. Chasing molecules that were never there: misassigned natural products and the role of chemical synthesis in modern structure elucidation. Angew Chem Int Ed Engl 2007; 44:1012-1044. [PMID: 15688428 DOI: 10.1002/anie.200460864] [Citation(s) in RCA: 472] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Over the course of the past half century, the structural elucidation of unknown natural products has undergone a tremendous revolution. Before World War II, a chemist would have relied almost exclusively on the art of chemical synthesis, primarily in the form of degradation and derivatization reactions, to develop and test structural hypotheses in a process that often took years to complete when grams of material were available. Today, a battery of advanced spectroscopic methods, such as multidimensional NMR spectroscopy and high-resolution mass spectrometry, not to mention X-ray crystallography, exist for the expeditious assignment of structures to highly complex molecules isolated from nature in milligram or sub-milligram quantities. In fact, it could be argued that the characterization of natural products has become a routine task, one which no longer even requires a reaction flask! This Review makes the case that imaginative detective work and chemical synthesis still have important roles to play in the process of solving nature's most intriguing molecular puzzles.
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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, Fax: (+1) 858-784-2469
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Scott A Snyder
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA, Fax: (+1) 858-784-2469
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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Affiliation(s)
- Eun Joo Kang
- Department of Chemistry, College of Natural Sciences, Seoul National University, Korea
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30
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Abstract
Our bodies are made of molecules, and it is from molecules that we derive our strength and joys. The joys of molecules manifest themselves in many ways. These include beautiful colors, exquisite aromas, distinct tastes, psychological ups and downs, and intellectual inspirations, among other forms of stimulation, material or spiritual. In this Perspective, written on the occasion of the 2005 American Chemical Society Arthur C. Cope Award address, I recount some of the joys I have experienced and shared with my students during campaigns to synthesize some of Nature's most intriguing and complex molecules.
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Affiliation(s)
- K C Nicolaou
- Department of Chemistry and Skaggs Institute for Chemical Biology, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
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Nicolaou KC, Snyder SA. Die Jagd auf Moleküle, die nie existiert haben: Falsch zugeordnete Naturstoffstrukturen und die Rolle der chemischen Synthese in der modernen Strukturaufklärung. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200460864] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- K. C. Nicolaou
- Department of Chemistry und The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA, Fax: (+1) 858‐784‐2469
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Scott A. Snyder
- Department of Chemistry und The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA, Fax: (+1) 858‐784‐2469
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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32
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Ikejiri M, Miyashita K, Tsunemi T, Imanishi T. A novel and efficient method for inside selective esterification of terminal vic -diols. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2003.11.128] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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35
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Yeung KS, Paterson I. Actin-bindende marine Makrolide: Totalsynthese und biologische Bedeutung. Angew Chem Int Ed Engl 2002. [DOI: 10.1002/ange.200290059] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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36
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Yeung KS, Paterson I. Actin-binding marine macrolides: total synthesis and biological importance. Angew Chem Int Ed Engl 2002; 41:4632-53. [PMID: 12481316 DOI: 10.1002/anie.200290057] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Marine organisms produce a fascinating range of structurally diverse secondary metabolites, which often possess unusual and sometimes unexpected biological activities. This structural diversity makes these marine natural products excellent molecular probes for the investigation of biochemical pathways. Recently, a number of novel and stereochemically complex macrolides, having a large macrolactone (22- to 44-membered) ring, that interact with the actin cycloskeleton have been isolated from different marine sources. Actin, like tubulin, is a major component of the cytoskeleton and has important cellular functions. Although the details of these interactions are still under investigation, these marine macrolides are becoming increasingly important as novel molecular probes to help elucidate the cellular functions of actin. Owing to their potent antitumor activities, these compounds, for example the aplyronines, also have potential for preclinical development in cancer chemotherapy. Their appealing molecular structures, with an abundance of stereochemistry, and biological significance, coupled with the extremely limited availability from the marine sources, have stimulated enormous interest in the synthesis of these compounds. This review summarizes the biological properties of these unusual marine natural products and features the recently completed total syntheses of swinholide A, scytophycin C, aplyronine A, mycalolide A--all of these being potent cytotoxic agents that target actin--and a diastereoisomer of ulapualide A. Rather than detailing each individual step of these multistep total syntheses, the different synthetic strategies, key reactions, and methods adopted for controlling the stereochemistry are compared.
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Affiliation(s)
- Kap-Sun Yeung
- University Chemical Laboratory, Lensfield Road, Cambridge, CB2 1EW, UK.
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37
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Job A, Janeck CF, Bettray W, Peters R, Enders D. The SAMP-/RAMP-hydrazone methodology in asymmetric synthesis. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)00080-7] [Citation(s) in RCA: 215] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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38
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Nicolaou KC, Mitchell HJ. Adventures in Carbohydrate Chemistry: New Synthetic Technologies, Chemical Synthesis, Molecular Design, and Chemical Biology. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3773(20010504)40:9<1576::aid-anie15760>3.0.co;2-g] [Citation(s) in RCA: 329] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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39
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Nicolaou KC, Mitchell HJ. Abenteuer in der Kohlenhydratchemie: Synthesestrategien, Synthesemethoden, Moleküldesign und biologische Chemie. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20010504)113:9<1624::aid-ange16240>3.0.co;2-n] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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40
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41
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Ide M, Nakata M. Room-Temperature Metallation of 2-Substituted 1,3-Dithiane Derivatives and Subsequent Coupling with 2,3-Disubstituted Oxiranes. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1999. [DOI: 10.1246/bcsj.72.2491] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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42
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Keck GE, Lundquist GD. Synthetic Studies toward the Total Synthesis of Swinholide. 1. Stereoselective Construction of the C19−C35 Subunit. J Org Chem 1999. [DOI: 10.1021/jo990291y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gary E. Keck
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84102
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43
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Affiliation(s)
- D J Faulkner
- Scripps Institution of Oceanography, University of California at San Diego, La Jolla 92093-0212, USA
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44
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Studies directed toward the total synthesis of scytophycin C: Synthesis of the C(1)C(18) fragment of scytophycin C. Tetrahedron Lett 1998. [DOI: 10.1016/s0040-4039(97)10852-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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45
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Priepke H, Brückner R. A Butyrolactone → 1,3-diol Strategy for the Obtention ofTolypothrix Polyethers – Total Synthesis of theTolypothrix Pentaether from Enantiomerically EnrichedS-Glycidol. European J Org Chem 1997. [DOI: 10.1002/jlac.199719970805] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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46
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Smith AB, Condon SM, McCauley JA, Leazer JL, Leahy JW, Maleczka RE. A Unified Total Synthesis of the Immunomodulators (−)-Rapamycin and (−)-27-Demethoxyrapamycin: Construction of the C(21−42) Perimeters. J Am Chem Soc 1997. [DOI: 10.1021/ja963066w] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Amos B. Smith
- Contribution from the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Stephen M. Condon
- Contribution from the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - John A. McCauley
- Contribution from the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Johnnie L. Leazer
- Contribution from the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - James W. Leahy
- Contribution from the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Robert E. Maleczka
- Contribution from the Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104
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47
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Nagasawa K, Shimizu I, Nakata T. Total synthesis of preswinholide A. 1. Stereoselective synthesis of the C11C23 segment. Tetrahedron Lett 1996. [DOI: 10.1016/0040-4039(96)01503-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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48
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Nicolaou KC, Patron AP, Ajito K, Richter PK, Khatuya H, Bertinato P, Miller RA, Tomaszewski MJ. Total Synthesis of Swinholide A, Preswinholide A, and Hemiswinholide A. Chemistry 1996. [DOI: 10.1002/chem.19960020718] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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49
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Bioactive marine macrolides. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s1572-5995(96)80015-9] [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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