1
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Hoskin JF, Jeong M, Siler DA, Ebner DC, Sorensen EJ. Development of a Divergent Synthesis of Pleurotinoid Natural Products. J Org Chem 2024; 89:8551-8561. [PMID: 38841743 DOI: 10.1021/acs.joc.4c00468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
Herein, we describe the evolution of our syntheses of the pleurotinoid natural products pleurotin (1), pleurogrisein (3), and 4-hydroxypleurogrisein (4). An approach based on a proximity-induced intramolecular Diels-Alder cycloaddition of a transient ortho-quinone dimethide (e.g., 6, Scheme 1) was inferior to an alternative construction featuring Gao's titanium(IV)-mediated photoenolization Diels-Alder coupling of ortho-tolualdehyde 20 with functionalized hydrindenone 22. While this pairing exhibited the desired stereoface selectivity and produced cis-fused hydrindanone 23, the successful realization of our syntheses of 1, 3, and 4 required a post-Diels-Alder epimerization of the unactivated stereocenter at C-5 in compound 23. Ultimately, it was possible to generate a reactive oxygen-centered radical via a reductive homolytic cleavage of the N-O bond in 23 and capitalize on its ability to break the C5-H bond in an intramolecular 1,5-hydrogen atom transfer (HAT). The carbon radical arising from this pivotal 1,5-HAT was subsequently trapped in situ by an exogenous thiol in a kinetically controlled HAT reaction to establish the natural configuration at C-5. The successful flipping of the cis-hydrindane in 23 to the challenging trans configuration in 24 provided a firm foundation for a formal synthesis of pleurotin (1), as well as syntheses of pleurogrisein (3) and 4-hydroxypleurogrisein (4).
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Affiliation(s)
- John F Hoskin
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Myungeun Jeong
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - David A Siler
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - David C Ebner
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Erik J Sorensen
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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2
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Yang F, Lin P, Xu B, Gao Y, Su W. Substituent-Determined Intramolecular Hydrogen Transfer for Photopromoted Intermolecular Cycloaddition of Anthraquinones with Aryl Olefins. Org Lett 2023; 25:8308-8313. [PMID: 37955848 DOI: 10.1021/acs.orglett.3c03354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
The formation of intramolecular hydrogen bonds in anthraquinones makes them inert to photoinduced reactions; therefore, it is a great challenge to phototransform these compounds. Herein, we reported a formal visible-light-induced [4 + 2] cycloaddition of both 1-hydroxyanthraquinones and 1-aminoanthraquinones with olefins under external photocatalyst-free conditions with high regioselectivity. More than 60 substrates are disclosed, demonstrating the reliability of this protocol to construct diverse functionalized anthraquinone derivatives.
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Affiliation(s)
- Fanyuanhang Yang
- State Key Laboratory of Structural Chemistry, Center for Excellence in Molecular Synthesis, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao Road West, Fuzhou 350002, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ping Lin
- State Key Laboratory of Structural Chemistry, Center for Excellence in Molecular Synthesis, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao Road West, Fuzhou 350002, China
| | - Biping Xu
- State Key Laboratory of Structural Chemistry, Center for Excellence in Molecular Synthesis, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao Road West, Fuzhou 350002, China
| | - Yuzhen Gao
- State Key Laboratory of Structural Chemistry, Center for Excellence in Molecular Synthesis, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao Road West, Fuzhou 350002, China
| | - Weiping Su
- State Key Laboratory of Structural Chemistry, Center for Excellence in Molecular Synthesis, Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao Road West, Fuzhou 350002, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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3
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Singha T, Kadam GA, Hari DP. Photocatalyzed Dowd-Beckwith radical-polar crossover reaction for the synthesis of medium-sized carbocyclic compounds. Chem Sci 2023; 14:6930-6935. [PMID: 37389258 PMCID: PMC10306080 DOI: 10.1039/d3sc01908j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 05/24/2023] [Indexed: 07/01/2023] Open
Abstract
The Dowd-Beckwith reaction, a ring-expansion of carbonyl compounds via alkoxy radicals, is a powerful approach for synthesizing medium to large-sized carbocyclic scaffolds, which takes advantage of existing ring structures and avoids entropic and enthalpic factors that arise from the end-to-end cyclization strategies. However, the Dowd-Beckwith ring-expansion followed by H-atom abstraction is still the dominating pathway, which hampers its synthetic applications, and there currently exist no reports on the functionalization of ring-expanded radicals using non-carbon based nucleophilic reagents. Herein, we report a redox-neutral decarboxylative Dowd-Beckwith/radical-polar crossover (RPC) sequence that delivers functionalized medium-sized carbocyclic compounds with broad functional group tolerance. The reaction allows one-carbon ring-expansion of 4-, 5-, 6-, 7-, and 8-membered ring substrates and can also be applied to three-carbon chain incorporation, enabling remote functionalization in medium-sized rings.
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Affiliation(s)
- Tushar Singha
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560012 India
| | - Ganesh Arjun Kadam
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560012 India
| | - Durga Prasad Hari
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560012 India
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4
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Yu T, Yang J, Wang Z, Ding Z, Xu M, Wen J, Xu L, Li P. Selective [2σ + 2σ] Cycloaddition Enabled by Boronyl Radical Catalysis: Synthesis of Highly Substituted Bicyclo[3.1.1]heptanes. J Am Chem Soc 2023; 145:4304-4310. [PMID: 36763965 DOI: 10.1021/jacs.2c13740] [Citation(s) in RCA: 40] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
In contrast to the traditional and widely-used cycloaddition reactions involving at least a π bond component, a [2σ + 2σ] radical cycloaddition between bicyclo[1.1.0]butanes (BCBs) and cyclopropyl ketones has been developed to provide a modular, concise, and atom-economical synthetic route to substituted bicyclo[3.1.1]heptane (BCH) derivatives that are 3D bioisosteres of benzenes and core skeleton of a number of terpene natural products. The reaction was catalyzed by a combination of simple tetraalkoxydiboron(4) compound B2pin2 and 3-pentyl isonicotinate. The broad substrate scope has been demonstrated by synthesizing a series of new highly functionalized BCHs with up to six substituents on the core with up to 99% isolated yield. Computational mechanistic investigations supported a pyridine-assisted boronyl radical catalytic cycle.
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Affiliation(s)
- Tao Yu
- Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710054, China
| | - Jinbo Yang
- School of Chemistry and Chemical Engineering/Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University, Shihezi 832003, China
| | - Zhijun Wang
- School of Chemistry and Chemical Engineering/Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University, Shihezi 832003, China
| | - Zhengwei Ding
- Department of Medicinal Chemistry, School of Pharmacy, Xi'an Jiaotong University, Xi'an 710061, China
| | - Ming Xu
- Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710054, China
| | - Jingru Wen
- Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710054, China
| | - Liang Xu
- School of Chemistry and Chemical Engineering/Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi University, Shihezi 832003, China
| | - Pengfei Li
- Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710054, China
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China
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5
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Ding S, Shi Y, Yang B, Hou M, He H, Gao S. Asymmetric Total Synthesis of Hasubanan Alkaloids: Periglaucines A-C, N,O-Dimethyloxostephine and Oxostephabenine. Angew Chem Int Ed Engl 2023; 62:e202214873. [PMID: 36357322 DOI: 10.1002/anie.202214873] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Indexed: 11/12/2022]
Abstract
We report herein the asymmetric total synthesis of periglaucines A-C, N,O-dimethyloxostephine and oxostephabenine. The key strategies used include: 1) a RhI -catalyzed regio- and diastereoselective Hayashi-Miyaura reaction to connect two necessary fragments; 2) an intramolecular photoenolization/Diels-Alder (PEDA) reaction to construct the highly functionalized tricyclic core skeleton bearing a quaternary center; 3) a bio-inspired intramolecular Michael addition and transannular acetalization to generate the aza[4.4.3]propellane and the tetrahydrofuran ring.
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Affiliation(s)
- Shaolei Ding
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
| | - Yingbo Shi
- College of Chemistry and Materials Science, Sichuan Normal University, 5 Jingan Road, Chengdu, 610068, China
| | - Baochao Yang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
| | - Min Hou
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
| | - Haibing He
- Shanghai Frontiers Science Center of Molecule Intelligent Syntheses, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
| | - Shuanhu Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China.,Shanghai Frontiers Science Center of Molecule Intelligent Syntheses, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China
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6
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French SA, Sumby CJ, Huang DM, George JH. Total Synthesis of Atrachinenins A and B. J Am Chem Soc 2022; 144:22844-22849. [DOI: 10.1021/jacs.2c09978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Sarah A. French
- Department of Chemistry, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Christopher J. Sumby
- Department of Chemistry, The University of Adelaide, Adelaide, SA 5005, Australia
| | - David M. Huang
- Department of Chemistry, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Jonathan H. George
- Department of Chemistry, The University of Adelaide, Adelaide, SA 5005, Australia
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7
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Naeini AA, Ziegelmeier AA, Chain WJ. Recent Developments with Icetexane Natural Products. Chem Biodivers 2022; 19:e202200793. [PMID: 36215180 PMCID: PMC11067433 DOI: 10.1002/cbdv.202200793] [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: 08/23/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022]
Abstract
Icetexane diterpenoids are a diverse family of natural products sourced from several species of terrestrial plants. Icetexanes exhibit a broad array of biological activities and together with their complex 6-7-6 tricyclic scaffolds, they have piqued the interest of synthetic organic chemists, natural products chemists, and biological investigators over the past four decades and were reviewed 13 years ago. This review summarizes icetexane natural products isolated since 2009, provides an overview of new synthetic approaches to the icetexane problem, and proposes an additional classification of icetexanes based on novel structures that are unlike previously isolated materials.
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Affiliation(s)
- Ali Amiri Naeini
- Department of Chemistry & Biochemistry, University of Delaware, Newark, DE 19716, United States
| | - Alexandre A Ziegelmeier
- Department of Chemistry & Biochemistry, University of Delaware, Newark, DE 19716, United States
| | - William J Chain
- Department of Chemistry & Biochemistry, University of Delaware, Newark, DE 19716, United States
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8
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Singha T, Rouf Samim Mondal A, Midya S, Prasad Hari D. The Dowd–Beckwith Reaction: History, Strategies, and Synthetic Potential. Chemistry 2022; 28:e202202025. [DOI: 10.1002/chem.202202025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Tushar Singha
- Department of Organic Chemistry Indian Institute of Scienece Bangalore 560012 India
| | | | - Suparnak Midya
- Department of Organic Chemistry Indian Institute of Scienece Bangalore 560012 India
| | - Durga Prasad Hari
- Department of Organic Chemistry Indian Institute of Scienece Bangalore 560012 India
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9
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Hoskin JF, Sorensen EJ. A Concise Synthesis of Pleurotin Enabled by a Nontraditional C-H Epimerization. J Am Chem Soc 2022; 144:14042-14046. [PMID: 35900919 DOI: 10.1021/jacs.2c06504] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An 8-step synthesis of a known pentacyclic intermediate toward the natural product pleurotin (1) is described. Pleurotin and related benzoquinone natural products are of great interest for their powerful anticancer and antibiotic activities. The route features a regio- and diastereoselective intermolecular photoenolization/Diels-Alder cycloaddition and an alkoxy-radical-induced hydrogen atom transfer-mediated C-H epimerization to construct pleurotin's carbon framework with appropriate relative stereochemical relationships. The synthesis concludes with a ring-forming benzylic C-H oxidation to deliver oxepane 19.
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Affiliation(s)
- John F Hoskin
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Erik J Sorensen
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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10
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Franov LJ, Hart JD, Pullella GA, Sumby CJ, George JH. Bioinspired Total Synthesis of Erectones A and B, and the Revised Structure of Hyperelodione D. Angew Chem Int Ed Engl 2022; 61:e202200420. [PMID: 35225410 PMCID: PMC9314102 DOI: 10.1002/anie.202200420] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Indexed: 12/22/2022]
Abstract
The field of biomimetic synthesis seeks to apply biosynthetic hypotheses to the efficient construction of complex natural products. This approach can also guide the revision of incorrectly assigned structures. Herein, we describe the evolution of a concise total synthesis and structural reassignment of hyperelodione D, a tetracyclic meroterpenoid derived from a Hypericum plant, alongside some biogenetically related natural products, erectones A and B. The key step in the synthesis of hyperelodione D forms six stereocentres and three rings in a bioinspired cascade reaction that features an intermolecular Diels-Alder reaction, an intramolecular Prins reaction and a terminating cycloetherification.
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Affiliation(s)
- Liam J Franov
- Department of Chemistry, University of Adelaide, Adelaide, SA 5000, Australia
| | - Jacob D Hart
- Department of Chemistry, University of Adelaide, Adelaide, SA 5000, Australia
| | - Glenn A Pullella
- Department of Chemistry, University of Adelaide, Adelaide, SA 5000, Australia
| | - Christopher J Sumby
- Department of Chemistry, University of Adelaide, Adelaide, SA 5000, Australia
| | - Jonathan H George
- Department of Chemistry, University of Adelaide, Adelaide, SA 5000, Australia
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11
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Aoyagi Y, Fujiwara K, Takahashi Y, Yano R, Hitotsuyanagi Y, Takeya K, Aiyama R, Matsuzaki T, Hashimoto S, Nishihara-Tsukashima A, Namatame M, Ishiyama A, Iwatsuki M, Otoguro K, Yamada H, Ōmura S. Semisynthesis of Antitrypanosomal <i>p</i>-Quinone Analog Possesing the Komaroviquinone Pharmacophore. Chem Pharm Bull (Tokyo) 2022; 70:300-303. [DOI: 10.1248/cpb.c21-00998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | - Koji Fujiwara
- School of Pharmacy, Tokyo University of Pharmacy & Life Sciences
| | | | - Reiko Yano
- College of Pharmacy, Kinjo Gakuin University
| | | | - Koichi Takeya
- School of Pharmacy, Tokyo University of Pharmacy & Life Sciences
| | | | | | | | | | | | - Aki Ishiyama
- Ōmura Satoshi Memorial Institute, Kitasato University
| | | | | | - Haruki Yamada
- Ōmura Satoshi Memorial Institute, Kitasato University
| | - Satoshi Ōmura
- Ōmura Satoshi Memorial Institute, Kitasato University
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12
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Franov LJ, Hart JD, Pullella GA, Sumby CJ, George JH. Bioinspired Total Synthesis of Erectones A and B, and the Revised Structure of Hyperelodione D. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Liam J. Franov
- Department of Chemistry University of Adelaide Adelaide SA 5000 Australia
| | - Jacob D. Hart
- Department of Chemistry University of Adelaide Adelaide SA 5000 Australia
| | - Glenn A. Pullella
- Department of Chemistry University of Adelaide Adelaide SA 5000 Australia
| | | | - Jonathan H. George
- Department of Chemistry University of Adelaide Adelaide SA 5000 Australia
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13
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Lopez E, Thorp SC, Mohan RS. Bismuth(III) compounds as catalysts in organic synthesis: A mini review. Polyhedron 2022. [DOI: 10.1016/j.poly.2022.115765] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Abstract
Natural product synthesis remains one of the most vibrant and intellectually rewarding areas of chemistry, although the justifications for pursuing it have evolved over time. In the early years, the emphasis lay on structure elucidation and confirmation through synthesis, as exemplified by celebrated studies on cocaine, morphine, strychnine and chlorophyll. This was followed by a phase where the sheer demonstration that highly complex molecules could be recreated in the laboratory in a rational manner was enough to justify the economic expense and intellectual agonies of a synthesis. Since then, syntheses of natural products have served as platforms for the demonstration of elegant strategies, for inventing new methodology 'on the fly' or to demonstrate the usefulness and scope of methods established with simpler molecules. We now add another aspect that we find fascinating, viz. 'natural product anticipation'. In this Review, we survey cases where the synthesis of a compound in the laboratory has preceded its isolation from nature. The focus of our Review lies on examples where this anticipation of a natural product has triggered a successful search or where synthesis and isolation have occurred independently. Finally, we highlight cases where a potential natural product structure has been suggested as a result of synthetic endeavours but not yet confirmed by isolation, inviting further collaborations between synthetic and natural product chemists.
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15
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Wang JYJ, Blyth MT, Sherburn MS, Coote ML. Tuning Photoenolization-Driven Cycloadditions Using Theory and Spectroscopy. J Am Chem Soc 2022; 144:1023-1033. [PMID: 34991316 DOI: 10.1021/jacs.1c12174] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The first broad spectrum investigation into the photoenolization/Diels-Alder (PEDA) sequence was carried out using M06-2X/6-31+G(d,p) in conjunction with SMD solvation and supported by experimental UV-vis spectroscopy. A test set of 20 prodienes was chosen to examine the role of the H atom acceptor group (substituted and unsubstituted carbonyl, thiocarbonyl, and imine), the H atom donor group, and bystander ring substituents. As reaction partners for the photogenerated dienes, a diverse test set of 20 dienophiles was examined, comprising electron rich, electron poor, neutral, strain activated, hydrocarbon, and heteroatom-containing molecules including CO2 and CO. A key finding of this work is the demonstration that the PEDA sequence of carbonyl based prodienes is tolerant of most substitution patterns. Another is that thiocarbonyl derivatives should behave analogously to the carbonyls but are likely to do so much more slowly, due to an inefficient intersystem crossing, an endothermic 1,5-hydrogen atom transfer (HAT) step, and a [1,5] sigmatropic H shift to regenerate the starting material that outcompetes the [4 + 2]cycloaddition. In contrast, the T1 state of the ortho-alkyl imines displays the incorrect orbital symmetry for 1,5-HAT and is correspondingly accompanied by higher barriers, even in the excited state. However, provided these barriers can be overcome, the remaining steps in the PEDA sequence are predicted to be facile. The Diels-Alder reaction is predicted to be of much broader scope than reported synthetic literature: while electron poor dienophiles are expected to be the most reactive partners, ethylene and electron rich alkenes should react at a synthetically useful rate. CO is predicted to undergo a facile (4 + 1)cheletropic addition instead of the normal [4 + 2]cycloaddition pathway. This unique photoenolization/cheletropic addition (PECA) sequence could provide metal-free access to benzannelated cyclopentanones.
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Affiliation(s)
- Jiao Yu J Wang
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Mitchell T Blyth
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Michael S Sherburn
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Michelle L Coote
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
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16
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Hu R, Chen J, Wang Z, Shang D, Yu L, Chan PWH, Rao W. THF-Enabled PtBr 2-Catalyzed Desymmetric Hydrogenative [3 + 2] Cycloaddition of 2-Alkynylbenzaldehyde-Tethered Cyclohexadienones. Org Chem Front 2022. [DOI: 10.1039/d2qo00593j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A THF-enabled PtBr2-catalyzed desymmetric hydrogenative [3 + 2] cycloaddition of 2-alkynylbenzaldehyde-tethered cyclohexadienones has been developed. The protocol provides a highly functionalized 6-7-6 polycyclic skeleton with four contiguous stereocenters in good...
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17
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Yang L, Li WY, Hou L, Zhan T, Cao W, Liu X, Feng X. Nickel II-catalyzed asymmetric photoenolization/Mannich reaction of (2-alkylphenyl) ketones. Chem Sci 2022; 13:8576-8582. [PMID: 35974747 PMCID: PMC9337722 DOI: 10.1039/d2sc02721f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 06/21/2022] [Indexed: 11/21/2022] Open
Abstract
A diastereo- and enantioselective photoenolization/Mannich (PEM) reaction of ortho-alkyl aromatic ketones with benzosulfonimides was established by utilizing a chiral N,N′-dioxide/Ni(OTf)2 complex as the Lewis acid catalyst. It afforded a series of benzosulfonamides and the corresponding ring-closure products, and a reversal of diastereoselectivity was observed through epimerization of the benzosulfonamide products under continuous irradiation. On the basis of the control experiments, the role of the additive LiNTf2 in achieving high stereoselectivity was elucidated. This PEM reaction was proposed to undergo a direct nucleophilic addition mechanism rather than a hetero-Diels–Alder/ring-opening sequence. A possible transition state model with a photoenolization process was proposed to explain the origin of the high level of stereoinduction. A diastereo- and enantioselective photoenolization/Mannich (PEM) reaction of (2-alkylphenyl) ketones with benzosulfonimides is realized by a chiral N,N′-dioxide/NiII complex catalyst.![]()
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Affiliation(s)
- Liangkun Yang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Wang-Yuren Li
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Liuzhen Hou
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Tangyu Zhan
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Weidi Cao
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
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18
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Zhang Q, He H, Gao S. Total Synthesis of Streptovertidione and Bioinspired Transformation to Streptovertidine A and Formicapyridine A. Chem Commun (Camb) 2022; 58:4239-4242. [DOI: 10.1039/d2cc00947a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report herein a concise total synthesis of streptovertidione, and its transformation to streptovertidine A and formicapyridine A through a bioinspired pyridination. This stratage features: 1) a one-pot Ti(O-iPr)4-mediated photoenolization/Diels-Alder...
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19
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Serna AV, Kürti L, Siitonen JH. Synthesis of (±)‐Setigerumine I: Biosynthetic Origins of the Elusive Racemic
Papaveraceae
Isoxazolidine Alkaloids**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111049] [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)
- Ana V. Serna
- Department of Chemistry Rice University 6500 Main Street Houston TX 77030 USA
| | - László Kürti
- Department of Chemistry Rice University 6500 Main Street Houston TX 77030 USA
| | - Juha H. Siitonen
- Department of Chemistry Rice University 6500 Main Street Houston TX 77030 USA
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Serna AV, Kürti L, Siitonen JH. Synthesis of (±)-Setigerumine I: Biosynthetic Origins of the Elusive Racemic Papaveraceae Isoxazolidine Alkaloids*. Angew Chem Int Ed Engl 2021; 60:27236-27240. [PMID: 34706137 DOI: 10.1002/anie.202111049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Indexed: 11/09/2022]
Abstract
The biosynthetic origins of the structurally related racemic isoxazolidine Papaveraceae alkaloids Setigerumine I, Dactylicapnosinine and Dactylicapnosine have remained elusive since their original isolation over two decades ago. Herein we report the first biosynthetic hypothesis for their formation and, inspired by it, the first synthesis of (±)-Setigerumine I with accompanying computational rationale. Based on the results, these isoxazolidine alkaloids arise from racemizing oxidative rearrangements of prominent isoquinoline alkaloids Noscapine and Hydrastine. The key steps featured in this synthesis are a room temperature Cope elimination and a domino oxidation/inverse-electron demand 1,3-dipolar cycloaddition of an axially chiral, yet configurationally unstable, intermediate. The work opens this previously inaccessible family of natural products for biological studies.
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Affiliation(s)
- Ana V Serna
- Department of Chemistry, Rice University, 6500 Main Street, Houston, TX, 77030, USA
| | - László Kürti
- Department of Chemistry, Rice University, 6500 Main Street, Houston, TX, 77030, USA
| | - Juha H Siitonen
- Department of Chemistry, Rice University, 6500 Main Street, Houston, TX, 77030, USA
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Hou M, Xu M, Yang B, He H, Gao S. Exo-Selective and Enantioselective Photoenolization/Diels-Alder Reaction. Org Lett 2021; 23:7487-7491. [PMID: 34550708 DOI: 10.1021/acs.orglett.1c02719] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
An unusual exo-selective photoenolization/Diels-Alder reaction of electron-rich 2-methylbenzaldehydes and dienophiles containing a benzoyl group at its α position was reported herein. The chiral TADDOL-type ligand plays a key role in this process: (1) accelerating the reaction; (2) controlling the enantioselectivity; and (3) improving and tuning the diastereoselectivity of the reaction.
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Affiliation(s)
- Min Hou
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663N Zhongshan Road, Shanghai 200062, China
| | - Mengmeng Xu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663N Zhongshan Road, Shanghai 200062, China
| | - Baochao Yang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663N Zhongshan Road, Shanghai 200062, China
| | - Haibing He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, 3663N Zhongshan Road, Shanghai 200062, China
| | - Shuanhu Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663N Zhongshan Road, Shanghai 200062, China.,Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, 3663N Zhongshan Road, Shanghai 200062, China
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Xu M, Hou M, He H, Gao S. Asymmetric Total Synthesis of Aglacins A, B, and E. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mengmeng Xu
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University China
| | - Min Hou
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University China
| | - Haibing He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
| | - Shuanhu Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University China
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
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Xu M, Hou M, He H, Gao S. Asymmetric Total Synthesis of Aglacins A, B, and E. Angew Chem Int Ed Engl 2021; 60:16655-16660. [PMID: 34008314 DOI: 10.1002/anie.202105395] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Indexed: 12/16/2022]
Abstract
An asymmetric photoenolization/Diels-Alder (PEDA) reaction between electron-rich 2-methylbenzaldehydes and unsaturated γ-lactones was developed to directly construct the basic tricyclic core of aryltetralin lactone lignans. This methodology enabled the first asymmetric total synthesis of aglacins A, B, and E and revision of the absolute configuration of these natural lignans. The strategy was also used to prepare the naturally occurring aryldihydronaphthalene-type lignans (-)-7,8-dihydroisojusticidin B and (+)-linoxepin in four and six steps, as well as 27 natural-product-like molecules containing a C8' quaternary center. We believe that the synthetic aglacins and small-molecule library provide new opportunities to carry out the SAR studies of the podophyllotoxin family of natural products.
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Affiliation(s)
- Mengmeng Xu
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, China
| | - Min Hou
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, China
| | - Haibing He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Shuanhu Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, China.,Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
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