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Novikov MA, Bobrova AY, Mezentsev IA, Medvedev MG, Tomilov YV. (2-Fluoroallyl)boration of Ketones with (2-Fluoroallyl)boronates. J Org Chem 2020; 85:6295-6308. [DOI: 10.1021/acs.joc.9b03445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Maxim A. Novikov
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., 119991 Moscow, Russian Federation
| | - Angelina Yu. Bobrova
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., 119991 Moscow, Russian Federation
- Higher Chemical College of the Russian Academy of Sciences, D. I. Mendeleev University of Chemical Technology of Russia, 9 Miusskaya pl., 125047 Moscow, Russian Federation
| | - Igor A. Mezentsev
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., 119991 Moscow, Russian Federation
- Higher Chemical College of the Russian Academy of Sciences, D. I. Mendeleev University of Chemical Technology of Russia, 9 Miusskaya pl., 125047 Moscow, Russian Federation
| | - Michael G. Medvedev
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., 119991 Moscow, Russian Federation
| | - Yury V. Tomilov
- N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., 119991 Moscow, Russian Federation
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52
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McClymont KS, Wang FY, Minakar A, Baran PS. Total Synthesis of (-)-Maximiscin. J Am Chem Soc 2020; 142:8608-8613. [PMID: 32338003 DOI: 10.1021/jacs.0c03202] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A short, enantioselective synthesis of (-)-maximiscin, a structurally intriguing metabolite of mixed biosynthetic origin, is reported. A retrosynthetic analysis predicated on maximizing ideality and efficiency led to several unusual disconnections and tactics. Formation of the central highly oxidized pyridone ring through a convergent coupling at the end of the synthesis simplified the route considerably. The requisite building blocks could be prepared from feedstock materials (derived from shikimate and mesitylene). Strategies rooted in hidden symmetry recognition, C-H functionalization, and radical retrosynthesis played key roles in developing this concise route.
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Affiliation(s)
- Kyle S McClymont
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Feng-Yuan Wang
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Amin Minakar
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Phil S Baran
- Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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Hu YJ, Li LX, Han JC, Min L, Li CC. Recent Advances in the Total Synthesis of Natural Products Containing Eight-Membered Carbocycles (2009-2019). Chem Rev 2020; 120:5910-5953. [PMID: 32343125 DOI: 10.1021/acs.chemrev.0c00045] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Natural products containing eight-membered carbocycles constitute a class of structurally intriguing and biologically important molecules such as the famous diterpenes taxol and vinigrol. Such natural products are being increasingly investigated because of their fascinating architectural features and potent medicinal properties. However, synthesis of natural products with cyclooctane moieties has proved to be highly challenging. This review highlights the recently completed total syntheses of natural products with eight-membered carbocycles with a focus on strategic considerations. A collection of 27 representative studies from the literature covering the decade from 2009 to 2019 is described in chronological order with relevant studies grouped together, including syntheses of the same natural product by different research groups using different strategies. Finally, a summary and outlook including a discussion of the major features of each strategy used in the syntheses are presented. This review illustrates the diversity and creativity in the elegant synthetic designs of eight-membered carbocycles. We hope this review will provide timely illumination and beneficial guidance for future synthetic efforts for organic chemists who are interested in this area.
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Affiliation(s)
- Ya-Jian Hu
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Li-Xuan Li
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Jing-Chun Han
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Long Min
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
| | - Chuang-Chuang Li
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
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Qu Y, Wang Z, Zhang Z, Zhang W, Huang J, Yang Z. Asymmetric Total Synthesis of (+)-Waihoensene. J Am Chem Soc 2020; 142:6511-6515. [DOI: 10.1021/jacs.0c02143] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Yongzheng Qu
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Zheyuan Wang
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Zhongchao Zhang
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Wendou Zhang
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Jun Huang
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Zhen Yang
- Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education and Beijing National Laboratory for Molecular Science, and Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- Shenzhen Bay Laboratory, Shenzhen 518055, China
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Deng J, Ning Y, Tian H, Gui J. Divergent Synthesis of Antiviral Diterpenes Wickerols A and B. J Am Chem Soc 2020; 142:4690-4695. [PMID: 32073850 DOI: 10.1021/jacs.9b11838] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Wickerols A and B are diterpene natural products that have a novel fused 6-5-6-6 ring framework and exhibit potent antiviral activity against the H1N1 type A influenza virus. Herein, we report a divergent synthesis of wickerols A and B in 16 and 15 steps, respectively, from commercial sitolactone. The key reactions of the synthesis are a SmI2-mediated intramolecular ketone-allylic acetate reductive cyclization, a Claisen rearrangement, and an intramolecular alkylation/aldol reaction that rapidly assembled the compact tetracyclic core framework in a stereocontrolled manner. The work described herein allowed us to confirm the absolute configurations of wickerols A and B.
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Affiliation(s)
- Jiachen Deng
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Yuhan Ning
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Hailong Tian
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Jinghan Gui
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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56
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Wang Z. Construction of all-carbon quaternary stereocenters by catalytic asymmetric conjugate addition to cyclic enones in natural product synthesis. Org Chem Front 2020. [DOI: 10.1039/d0qo00763c] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This review discusses the construction of all-carbon quaternary stereocenters using catalytic asymmetric conjugate addition and its application in natural product synthesis.
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Affiliation(s)
- Zhuo Wang
- Southern University of Science and Technology
- School of Medicine
- Shenzhen
- People's Republic of China
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57
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Beemelmanns C, Nitsch D, Bentz C, Reissig HU. Stereoselective Cascade Cyclizations with Samarium Diiodide to Tetracyclic Indolines: Precursors of Fluorostrychnines and Brucine. Chemistry 2019; 25:8780-8789. [PMID: 31033048 DOI: 10.1002/chem.201900087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 04/25/2019] [Indexed: 12/16/2022]
Abstract
A series of γ-indolylketones with fluorine, cyano or alkoxy substituents at the benzene moiety was prepared and subjected to samarium diiodide-promoted cyclization reactions. The desired dearomatizing ketyl cascade reaction forming two new rings proceeded in all cases with high diastereoselectivity, but with differing product distribution. In most cases, the desired annulated tetracyclic compounds were obtained in moderate to good yields, but as second product tetracyclic spirolactones were isolated in up to 29 % yield. The reaction rate was influenced by the substituents at the benzene moiety of the substrate as expected, with electron-accepting groups accelerating and electron-donating groups decelerating the cyclization process. In case of a difluoro-substituted γ-indolylketone a partial defluorination was observed. The intermediate samarium enolate of the tetracyclic products could be trapped by adding reactive alkylating agents as electrophiles delivering products with quarternary carbons. In the case of a dimethoxy-substituted tetracyclic cyclization product a subsequent reductive amination stereoselectively provided a pentacyclic compound that was subsequently N-protected and subjected to a regioselective elimination. The obtained functionalized pentacyclic product should be convertible into the alkaloid brucine by four well-established steps. Overall, the presented report shows that functionalized tetracyclic compounds with different substituents are rapidly available with the samarium diiodide cascade cyclization as crucial step. Hence, analogues of the landmark alkaloid strychnine, for example, with specific fluorine substitutions, should be easily accessible.
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Affiliation(s)
- Christine Beemelmanns
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195, Berlin, Germany.,Leibniz-Institut für Naturstoff-Forschung und Infektionsbiologie, Beutenbergstraße 11a, 07745, Jena, Germany
| | - Dominik Nitsch
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195, Berlin, Germany
| | - Christoph Bentz
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195, Berlin, Germany
| | - Hans-Ulrich Reissig
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195, Berlin, Germany
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58
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Llabani E, Hicklin RW, Lee HY, Motika SE, Crawford LA, Weerapana E, Hergenrother PJ. Diverse compounds from pleuromutilin lead to a thioredoxin inhibitor and inducer of ferroptosis. Nat Chem 2019; 11:521-532. [PMID: 31086302 PMCID: PMC6639018 DOI: 10.1038/s41557-019-0261-6] [Citation(s) in RCA: 156] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 03/25/2019] [Indexed: 02/08/2023]
Abstract
The chemical diversification of natural products provides a robust and general method for the creation of stereochemically rich and structurally diverse small molecules. The resulting compounds have physicochemical traits different from those in most screening collections, and as such are an excellent source for biological discovery. Herein, we subject the diterpene natural product pleuromutilin to reaction sequences focused on creating ring system diversity in few synthetic steps. This effort resulted in a collection of compounds with previously unreported ring systems, providing a novel set of structurally diverse and highly complex compounds suitable for screening in a variety of different settings. Biological evaluation identified the novel compound ferroptocide, a small molecule that rapidly and robustly induces ferroptotic death of cancer cells. Target identification efforts and CRISPR knockout studies reveal that ferroptocide is an inhibitor of thioredoxin, a key component of the antioxidant system in the cell. Ferroptocide positively modulates the immune system in a murine model of breast cancer and will be a useful tool to study the utility of pro-ferroptotic agents for treatment of cancer.
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Affiliation(s)
- Evijola Llabani
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA
| | - Robert W Hicklin
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA
| | - Hyang Yeon Lee
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA
| | - Stephen E Motika
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA
| | - Lisa A Crawford
- Department of Chemistry, Boston College, Chestnut Hill, MA, USA
| | | | - Paul J Hergenrother
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA.
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59
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Llabani E, Hicklin RW, Lee HY, Motika SE, Crawford LA, Weerapana E, Hergenrother PJ. Diverse compounds from pleuromutilin lead to a thioredoxin inhibitor and inducer of ferroptosis. Nat Chem 2019. [PMID: 31086302 DOI: 10.1021/acscentsci.9b00916/suppl_file/oc9b00916_si_001.pdf] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2023]
Abstract
The chemical diversification of natural products provides a robust and general method for the creation of stereochemically rich and structurally diverse small molecules. The resulting compounds have physicochemical traits different from those in most screening collections, and as such are an excellent source for biological discovery. Herein, we subject the diterpene natural product pleuromutilin to reaction sequences focused on creating ring system diversity in few synthetic steps. This effort resulted in a collection of compounds with previously unreported ring systems, providing a novel set of structurally diverse and highly complex compounds suitable for screening in a variety of different settings. Biological evaluation identified the novel compound ferroptocide, a small molecule that rapidly and robustly induces ferroptotic death of cancer cells. Target identification efforts and CRISPR knockout studies reveal that ferroptocide is an inhibitor of thioredoxin, a key component of the antioxidant system in the cell. Ferroptocide positively modulates the immune system in a murine model of breast cancer and will be a useful tool to study the utility of pro-ferroptotic agents for treatment of cancer.
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Affiliation(s)
- Evijola Llabani
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA
| | - Robert W Hicklin
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA
| | - Hyang Yeon Lee
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA
| | - Stephen E Motika
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA
| | - Lisa A Crawford
- Department of Chemistry, Boston College, Chestnut Hill, MA, USA
| | | | - Paul J Hergenrother
- Department of Chemistry, Roger Adams Laboratory, University of Illinois, Urbana, IL, USA.
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60
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Kennedy CR, Zhong H, Macaulay RL, Chirik PJ. Regio- and Diastereoselective Iron-Catalyzed [4+4]-Cycloaddition of 1,3-Dienes. J Am Chem Soc 2019; 141:8557-8573. [PMID: 31060353 DOI: 10.1021/jacs.9b02443] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A family of single-component iron precatalysts for the [4+4]-cyclodimerization and intermolecular cross-[4+4]-cycloaddition of monosubstituted 1,3-dienes is described. Cyclooctadiene products were obtained with high regioselectivity, and catalyst-controlled access to either cis- or trans-diastereomers was achieved using 4-substituted diene substrates. Reactions conducted either with single-component precatalysts or with iron dihalide complexes activated in situ proved compatible with common organic functional groups and were applied on multigram scale (up to >100 g). Catalytically relevant, S = 1 iron complexes bearing 2-(imino)pyridine ligands, (RPI)FeL2 (RPI = [2-(2,6-R2-C6H3-N═CMe)-C5H4N] where R = iPr or Me, L2 = bis-olefin), were characterized by single-crystal X-ray diffraction, Mößbauer spectroscopy, magnetic measurements, and DFT calculations. The structural and spectroscopic parameters are consistent with an electronic structure description comprised of a high spin iron(I) center ( SFe = 3/2) engaged in antiferromagnetically coupling with a ligand radical anion ( SPI = -1/2). Mechanistic studies conducted with these single-component precatalysts, including kinetic analyses, 12C/13C isotope effect measurements, and in situ Mößbauer spectroscopy, support a mechanism involving oxidative cyclization of two dienes that determines regio- and diastereoselectivity. Topographic steric maps derived from crystallographic data provided insights into the basis for the catalyst control through stereoselective oxidative cyclization and subsequent, stereospecific allyl-isomerization and C-C bond-forming reductive elimination.
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Affiliation(s)
- C Rose Kennedy
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Hongyu Zhong
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Rachel L Macaulay
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
| | - Paul J Chirik
- Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States
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61
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Yñigez-Gutierrez AE, Bachmann BO. Fixing the Unfixable: The Art of Optimizing Natural Products for Human Medicine. J Med Chem 2019; 62:8412-8428. [PMID: 31026161 DOI: 10.1021/acs.jmedchem.9b00246] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Molecules isolated from natural sources including bacteria, fungi, and plants are a long-standing source of therapeutics that continue to add to our medicinal arsenal today. Despite their potency and prominence in the clinic, complex natural products often exhibit a number of liabilities that hinder their development as therapeutics, which may be partially responsible for the current trend away from natural product discovery, research, and development. However, advances in synthetic biology and organic synthesis have inspired a new generation of natural product chemists to tackle powerful undeveloped scaffolds. In this Perspective, we will present case studies demonstrating the historical and current focus on making targeted, but significant, changes to natural product scaffolds via biosynthetic gene cluster manipulation, total synthesis, semisynthesis, or a combination of these methods, with a focus on increasing activity, decreasing toxicity, or improving chemical and pharmacological properties.
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Affiliation(s)
| | - Brian O Bachmann
- Department of Chemistry , Vanderbilt University , Nashville , Tennessee 37235 , United States
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Huffman BJ, Shenvi RA. Natural Products in the "Marketplace": Interfacing Synthesis and Biology. J Am Chem Soc 2019; 141:3332-3346. [PMID: 30682249 PMCID: PMC6446556 DOI: 10.1021/jacs.8b11297] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Drugs are discovered through the biological screening of collections of compounds, followed by optimization toward functional end points. The properties of screening collections are often balanced between diversity, physicochemical favorability, intrinsic complexity, and synthetic tractability (Huggins, D. J.; et al. ACS Chem. Biol. 2011, 6, 208; DOI: 10.1021/cb100420r ). Whereas natural product (NP) collections excel in the first three attributes, NPs suffer a disadvantage on the last point. Academic total synthesis research has worked to solve this problem by devising syntheses of NP leads, diversifying late-stage intermediates, or derivatizing the NP target. This work has led to the discovery of reaction mechanisms, the invention of new methods, and the development of FDA-approved drugs. Few drugs, however, are themselves NPs; instead, NP analogues predominate. Here we highlight past examples of NP analogue development and successful NP-derived drugs. More recently, chemists have explored how NP analogues alter the retrosynthetic analysis of complex scaffolds, merging structural design and synthetic design. This strategy maintains the intrinsic complexity of the NP but can alter the physicochemical properties of the scaffold, like core instability that renders the NP a poor chemotype. Focused libraries based on these syntheses may exclude the NP but maintain the molecular properties that distinguish NP space from synthetic space (Stratton, C. F.; et al. Bioorg. Med. Chem. Lett. 2015, 25, 4802; DOI: 10.1016/j.bmcl.2015.07.014 ), properties that have statistical advantages in clinical progression (Luker, T.; et al. Bioorg. Med. Chem. Lett. 2011, 21, 5673, DOI: 10.1016/j.bmcl.2011.07.074 ; Ritchie, T. J.; Macdonald, S. J. F. Drug Discovery Today 2009, 14, 1011, DOI: 10.1016/j.drudis.2009.07.014 ). Research that expedites synthetic access to NP motifs can prevent homogeneity of chemical matter available for lead discovery. Easily accessed, focused libraries of NP scaffolds can fill empty but active gaps in screening sets and expand the molecular diversity of synthetic collections.
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Affiliation(s)
- Benjamin J. Huffman
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Ryan A. Shenvi
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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63
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Fu Y, Liu Y, Yi Y, Liang J, Wu Q, Shang R. A Validated HPLC-MS/MS Assay for 14- O-[(4,6-Diaminopyrimidine-2-yl)thioacetyl] Mutilin in Biological Samples and Its Pharmacokinetic, Distribution and Excretion via Urine and Feces in Rats. Molecules 2019; 24:E790. [PMID: 30813235 PMCID: PMC6413085 DOI: 10.3390/molecules24040790] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 02/09/2019] [Accepted: 02/15/2019] [Indexed: 11/16/2022] Open
Abstract
14-O-[(4,6-Diaminopyrimidine-2-yl)thioacetyl] mutilin (DPTM), a novel pleuromutilin candidate with a substituted pyrimidine moiety, has been confirmed to possess excellent antibacterial activity against Gram-positive bacteria. To illustrate the pharmacokinetic profile after intravenous (i.v.), intramuscular (i.m.) and oral (p.o.) administrations with DPTM, as well as tissue distribution and excretion via urine and feces in vivo, a specific, sensitive and robust HPLC-MS/MS method was first developed to determine DPTM in rat plasma, various tissues, urine and feces. The plasma, tissues, urine and feces samples were treated by protein precipitation with acetonitrile using tiamulin fumarate as an internal standard (IS). This method which was achieved on an HPLC system detector equipped with an ESI interface, was sensitive with 5 ng/mL as the lower limit of detection and exhibited good linearity (R² > 0.9900) in the range of 5⁻4000 ng/mL for plasma, various tissues, urine and feces, as well as intra-day precision, inter-day precision and accuracy. The matrix effects ranged from 94.2 to 109.7% with RSD ≤ 9.4% and the mean extraction recoveries ranged from 95.4 to 109.5% in plasma, tissue homogenates, urine and feces (RSD ≤ 9.9). After i.v., i.m. and p.o. administrations, DPTM was rapidly absorbed and metabolized in rats with the half-life (t1/2) of 1.70⁻1.86, 3.23⁻3.49 and 4.38⁻4.70 for 10, 25 and 75 mg/kg doses, respectively. The tissue distribution showed that DPTM was diffused into all the tested tissues, especially into the intestine and lung. Excretion via urine and feces studies demonstrated that DPTM was mainly excreted by feces after administration.
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Affiliation(s)
- Yunxing Fu
- Key Laboratory of New Animal Drug Project of Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou 730050, China.
| | - Yu Liu
- Key Laboratory of New Animal Drug Project of Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou 730050, China.
| | - Yunpeng Yi
- Key Laboratory of New Animal Drug Project of Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou 730050, China.
| | - Jianping Liang
- Key Laboratory of New Animal Drug Project of Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou 730050, China.
| | - Qingfeng Wu
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
| | - Ruofeng Shang
- Key Laboratory of New Animal Drug Project of Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of CAAS, Lanzhou 730050, China.
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Goethe O, Heuer A, Ma X, Wang Z, Herzon SB. Antibacterial properties and clinical potential of pleuromutilins. Nat Prod Rep 2019; 36:220-247. [PMID: 29979463 DOI: 10.1039/c8np00042e] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Covering: up to 2018Pleuromutilins are a clinically validated class of antibiotics derived from the fungal diterpene (+)-pleuromutilin (1). Pleuromutilins inhibit bacterial protein synthesis by binding to the peptidyl transferase center (PTC) of the ribosome. In this review we summarize the biosynthesis and recent total syntheses of (+)-pleuromutilin (1). We review the mode of interaction of pleuromutilins with the bacterial ribosome, which involves binding of the C14 extension and the tricyclic core to the P and A sites of the PTC, respectively. We provide an overview of existing clinical agents, and discuss the three primary modes of bacterial resistance (mutations in ribosomal protein L3, Cfr methylation, and efflux). Finally we collect structure-activity relationships from publicly available reports, and close with some forward looking statements regarding future development.
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Affiliation(s)
- Olivia Goethe
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
| | - Abigail Heuer
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
| | - Xiaoshen Ma
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
| | - Zhixun Wang
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA.
| | - Seth B Herzon
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA. and Department of Pharmacology, Yale School of Medicine, New Haven, Connecticut 06520, USA
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Sui G, Lv Q, Song X, Guo H, Dai J, Ren L, Lee CS, Zhou W, Hao HD. Chemoselective reduction of aldehydes via a combination of NaBH 4 and acetylacetone. NEW J CHEM 2019. [DOI: 10.1039/c9nj03210j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A bench-stable combination of NaBH4–acetylacetone was developed for the efficient chemoselective reduction of aldehydes in the presence of ketones.
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Affiliation(s)
- Guoqing Sui
- Shaanxi Key Laboratory of Natural Products & Chemical Biology
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling
- China
| | - Qingyun Lv
- Shaanxi Key Laboratory of Natural Products & Chemical Biology
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling
- China
| | - Xiaoqing Song
- Shaanxi Key Laboratory of Natural Products & Chemical Biology
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling
- China
| | - Huihui Guo
- Shaanxi Key Laboratory of Natural Products & Chemical Biology
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling
- China
| | - Jiatong Dai
- Shaanxi Key Laboratory of Natural Products & Chemical Biology
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling
- China
| | - Li Ren
- Shaanxi Key Laboratory of Natural Products & Chemical Biology
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling
- China
| | - Chi-Sing Lee
- Department of Chemistry
- Hong Kong Baptist University
- Kowloon Tong
- China
| | - Wenming Zhou
- Shaanxi Key Laboratory of Natural Products & Chemical Biology
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling
- China
| | - Hong-Dong Hao
- Shaanxi Key Laboratory of Natural Products & Chemical Biology
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling
- China
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66
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Green SA, Crossley SWM, Matos JLM, Vásquez-Céspedes S, Shevick SL, Shenvi RA. The High Chemofidelity of Metal-Catalyzed Hydrogen Atom Transfer. Acc Chem Res 2018; 51:2628-2640. [PMID: 30406655 DOI: 10.1021/acs.accounts.8b00337] [Citation(s) in RCA: 190] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The implementation of any chemical reaction in a structurally complex setting ( King , S. M. J. Org. Chem. 2014 , 79 , 8937 ) confronts structurally defined barriers: steric environment, functional group reactivity, product instability, and through-bond electronics. However, there are also practical barriers. Late-stage reactions conducted on small quantities of material are run inevitably at lower than optimal concentrations. Access to late-stage material limits extensive optimization. Impurities from past reactions can interfere, especially with catalytic reactions. Therefore, chemical reactions on which one can rely at the front lines of a complex synthesis campaign emerge from the crucible of total synthesis as robust, dependable, and widely applied. Trost conceptualized "chemoselectivity" as a reagent's selective reaction of one functional group or reactive site in preference to others ( Trost , B. M. Science 1983 , 219 , 245 ). Chemoselectivity and functional group tolerance can be evaluated quickly using robustness screens ( Collins , K. D. Nat. Chem. 2013 , 5 , 597 ). A reaction may also be characterized by its "chemofidelity", that is, its reliable reaction with a functional group in any molecular context. For example, ketone reduction by an electride (dissolving metal conditions) exhibits high chemofidelity but low chemoselectivity: it usually works, but many other functional groups are reduced at similar rates. Conversely, alkene coordination chemistry effected by π Lewis acids can exhibit high chemoselectivity ( Trost , B. M. Science 1983 , 219 , 245 ) but low chemofidelity: it can be highly selective for alkenes but sensitive to the substitution pattern ( Larionov , E. Chem. Commun. 2014 , 50 , 9816 ). In contrast, alkenes undergo reliable, robust, and diverse hydrogen atom transfer reactions from metal hydrides to generate carbon-centered radicals. Although there are many potential applications of this chemistry, its functional group tolerance, high rates, and ease of execution have led to its rapid deployment in complex synthesis campaigns. Its success derives from high chemofidelity, that is, its dependable reactivity in many molecular environments and with many alkene substitution patterns. Metal hydride H atom transfer (MHAT) reactions convert diverse, simple building blocks to more stereochemically and functionally dense products ( Crossley , S. W. M. Chem. Rev. 2016 , 116 , 8912 ). When hydrogen is returned to the metal, MHAT can be considered the radical equivalent of Brønsted acid catalysis-itself a broad reactivity paradigm. This Account summarizes our group's contributions to method development, reagent discovery, and mechanistic interrogation. Our earliest contribution to this area-a stepwise hydrogenation with high chemoselectivity and high chemofidelity-has found application to many problems. More recently, we reported the first examples of dual-catalytic cross-couplings that rely on the merger of MHAT cycles and nickel catalysis. With time, we anticipate that MHAT will become a staple of chemical synthesis.
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Affiliation(s)
- Samantha A. Green
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Steven W. M. Crossley
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Jeishla L. M. Matos
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Suhelen Vásquez-Céspedes
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Sophia L. Shevick
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Ryan A. Shenvi
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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67
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Gao M, Wang Y, Yang K, He W, Yang X, Yao Z. Enantioselective Total Synthesis of (+)‐Plumisclerin A. Angew Chem Int Ed Engl 2018; 57:13313-13318. [DOI: 10.1002/anie.201808517] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 08/13/2018] [Indexed: 01/11/2023]
Affiliation(s)
- Ming Gao
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
| | - Ye‐Cheng Wang
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
| | - Kai‐Rui Yang
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
| | - Wei He
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
- STA Pharmaceutical Co. Ltd. 90 Delin Road, Waigaoqiao Shanghai China
| | - Xiao‐Liang Yang
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
| | - Zhu‐Jun Yao
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
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68
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Iyer A, Ahuja S, Jockusch S, Ugrinov A, Sivaguru J. Conjugate addition from the excited state. Chem Commun (Camb) 2018; 54:11021-11024. [PMID: 30215437 DOI: 10.1039/c8cc05924a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Conjugate addition occurs efficiently from excited hydrazide based acrylanilides under both UV and metal free visible light irradiations. The reaction proceeds via an excited state encounter complex that bifurcates either via an electron or energy transfer pathway. The generality of excited state conjugate addition is demonstrated using chloromethylation and by thiol addition.
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Affiliation(s)
- Akila Iyer
- Center for Photochemical Sciences and Department of Chemistry, Bowling Green State University, Bowling Green, OH 43403, USA.
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69
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Usami K, Yamaguchi E, Tada N, Itoh A. Visible-Light-Mediated Iminyl Radical Generation from Benzyl Oxime Ether: Synthesis of Pyrroline via Hydroimination Cyclization. Org Lett 2018; 20:5714-5717. [DOI: 10.1021/acs.orglett.8b02429] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Kaoru Usami
- Gifu Pharmaceutical University 1-25-4, Daigaku-nishi, Gifu 501-1196, Japan
| | - Eiji Yamaguchi
- Gifu Pharmaceutical University 1-25-4, Daigaku-nishi, Gifu 501-1196, Japan
| | - Norihiro Tada
- Gifu Pharmaceutical University 1-25-4, Daigaku-nishi, Gifu 501-1196, Japan
| | - Akichika Itoh
- Gifu Pharmaceutical University 1-25-4, Daigaku-nishi, Gifu 501-1196, Japan
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70
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Gao M, Wang Y, Yang K, He W, Yang X, Yao Z. Enantioselective Total Synthesis of (+)‐Plumisclerin A. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201808517] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Ming Gao
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
| | - Ye‐Cheng Wang
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
| | - Kai‐Rui Yang
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
| | - Wei He
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
- STA Pharmaceutical Co. Ltd. 90 Delin Road, Waigaoqiao Shanghai China
| | - Xiao‐Liang Yang
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
| | - Zhu‐Jun Yao
- State Key Laboratory of Coordination Chemistry andJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing University 163 Xianlin Avenue Nanjing Jiangsu 210023 China
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71
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Ma X, Kucera R, Goethe OF, Murphy SK, Herzon SB. Directed C-H Bond Oxidation of (+)-Pleuromutilin. J Org Chem 2018; 83:6843-6892. [PMID: 29664634 DOI: 10.1021/acs.joc.8b00462] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Antibiotics derived from the diterpene fungal metabolite (+)-pleuromutilin (1) are useful agents for the treatment Gram-positive infections in humans and farm animals. Pleuromutilins elicit slow rates of resistance development and minimal cross-resistance with existing antibiotics. Despite efforts aimed at producing new derivatives by semisynthesis, modification of the tricyclic core is underexplored, in part due to a limited number of functional group handles. Herein, we report methods to selectively functionalize the methyl groups of (+)-pleuromutilin (1) by hydroxyl-directed iridium-catalyzed C-H silylation, followed by Tamao-Fleming oxidation. These reactions provided access to C16, C17, and C18 monooxidized products, as well as C15/C16 and C17/C18 dioxidized products. Four new functionalized derivatives were prepared from the protected C17 oxidation product. C6 carboxylic acid, aldehyde, and normethyl derivatives were prepared from the C16 oxidation product. Many of these sequences were executed on gram scales. The efficiency and practicality of these routes provides an easy method to rapidly interrogate structure-activity relationships that were previously beyond reach. This study will inform the design of fully synthetic approaches to novel pleuromutilins and underscores the power of the hydroxyl-directed iridium-catalyzed C-H silylation reaction.
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72
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Zhu L, Hong R. Pursuing effective Gram-negative antibiotics: The chemical synthesis of negamycin. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.04.059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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73
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Baran PS. Natural Product Total Synthesis: As Exciting as Ever and Here To Stay. J Am Chem Soc 2018; 140:4751-4755. [DOI: 10.1021/jacs.8b02266] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Phil S. Baran
- The Scripps Research Institute, La Jolla, California
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74
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Hung K, Hu X, Maimone TJ. Total synthesis of complex terpenoids employing radical cascade processes. Nat Prod Rep 2018; 35:174-202. [PMID: 29417970 PMCID: PMC5858714 DOI: 10.1039/c7np00065k] [Citation(s) in RCA: 121] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Covering: 2011-2017Radical cyclizations have a rich history in organic chemistry and have been particularly generous to the field of natural product synthesis. Owing to their ability to operate in highly congested molecular quarters, and with significant functional group compatibility, these transformations have enabled the synthesis of numerous polycyclic terpenoid natural products over the past several decades. Moreover, when programmed accordingly into a synthetic plan, radical cascade processes can be used to rapidly assemble molecular complexity, much in the same way nature rapidly constructs terpene frameworks through cationic cyclization pathways. This review highlights recent total syntheses of complex terpenoids (from 2011-2017) employing C-C bond-forming radical cascade sequences.
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Affiliation(s)
- Kevin Hung
- Department of Chemistry, University of California - Berkeley, Berkeley, CA 94720, USA.
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75
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Jonker SJT, Diner C, Schulz G, Iwamoto H, Eriksson L, Szabó KJ. Catalytic asymmetric propargyl- and allylboration of hydrazonoesters: a metal-free approach to sterically encumbered chiral α-amino acid derivatives. Chem Commun (Camb) 2018; 54:12852-12855. [DOI: 10.1039/c8cc07908k] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Metal-free asymmetric catalysis for the synthesis of sterically encumbered amino-acids was developed using allyl- and allenylboronic acid reagents.
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Affiliation(s)
| | - Colin Diner
- Department of Organic Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
| | - Göran Schulz
- Department of Organic Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
| | - Hiroaki Iwamoto
- Department of Organic Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
| | - Lars Eriksson
- Department of Materials and Environmental Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
| | - Kálmán J. Szabó
- Department of Organic Chemistry
- Stockholm University
- SE-106 91 Stockholm
- Sweden
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