51
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Yamaguchi Y, Seino Y, Suzuki A, Kamei Y, Yoshino T, Kojima M, Matsunaga S. Intramolecular Hydrogen Atom Transfer Hydroarylation of Alkenes toward δ-Lactams Using Cobalt-Photoredox Dual Catalysis. Org Lett 2022; 24:2441-2445. [DOI: 10.1021/acs.orglett.2c00700] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Yuto Yamaguchi
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Yusuke Seino
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Akihiko Suzuki
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Yuji Kamei
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Tatsuhiko Yoshino
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
- Global Station for Biosurfaces and Drug Discovery, Hokkaido University, Sapporo 060-0812, Japan
| | - Masahiro Kojima
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
| | - Shigeki Matsunaga
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
- Global Station for Biosurfaces and Drug Discovery, Hokkaido University, Sapporo 060-0812, Japan
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52
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Kong L, Yu H, Deng M, Wu F, Jiang Z, Luo T. Enantioselective Total Syntheses of Grayanane Diterpenoids: (-)-Grayanotoxin III, (+)-Principinol E, and (-)-Rhodomollein XX. J Am Chem Soc 2022; 144:5268-5273. [PMID: 35297610 DOI: 10.1021/jacs.2c01692] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Enantioselective total syntheses of (-)-grayanotoxin III, (+)-principinol E, and (-)-rhodomollein XX were accomplished based on a convergent strategy. The left- and right-wing fragments were assembled via the diastereoselective Mukaiyama aldol reaction catalyzed by a chiral hydrogen bond donor. The unique 7-endo-trig cyclization based on a bridgehead carbocation forged the 5/7/6/5 tetracyclic skeleton that underwent redox manipulations and 1,2-migration to access different grayanane diterpenoids.
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Affiliation(s)
- Lingran Kong
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Hang Yu
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Mengping Deng
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Fanrui Wu
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Zhe Jiang
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Tuoping Luo
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.,Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.,Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, Guangdong 518055, China
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53
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Kim TT, Lee C, Kim D, Lee HS, Han S. Synthesis and Reactivity of 1-Hydroxyherquline A. Org Lett 2022; 24:1964-1968. [PMID: 35244406 DOI: 10.1021/acs.orglett.2c00379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herein, we present the synthesis of 1-hydroxyherquline A and describe its reactivity discovered during its attempted conversion to herquline A, a long-sought natural product target in the synthetic chemical community. The strategic installation of the C1 hydroxyl group enabled the key aza-Michael addition-mediated N10-C2 bond formation and eventually access to 1-hydroxyherquline A, the most advanced herquline A congener reported to date. Our attempted reductive transformation of 1-hydroxyherquline A to herquline A was challenged by the extremely strained bowl-shaped pentacyclic structures of key precursors that prevented either radical formation at C1 or protonation (or hydrogenation) from the desired face. These discoveries regarding the innate chemical reactivities of advanced intermediates toward herquline A may prove useful in efforts toward this formidable target.
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Affiliation(s)
- Thomas T Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Chungwoo Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Dongwook Kim
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Hee-Seung Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Sunkyu Han
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
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54
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Liu R, Xia M, Ling C, Fu S, Liu B. Construction of the Tetracyclic Core Structure of Dysiherbols A–C. Org Lett 2022; 24:1642-1646. [DOI: 10.1021/acs.orglett.2c00159] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Rong Liu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Mengwei Xia
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Cichang Ling
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Shaomin Fu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Bo Liu
- Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
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55
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Zhu T, Zhang XJ, Zhou Z, Xu Z, Ma M, Zhao B. Synthesis of functionalized malononitriles via Fe-catalysed hydrogen atom transfers of alkenes. Org Biomol Chem 2022; 20:1480-1487. [PMID: 35103271 DOI: 10.1039/d1ob02332b] [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
Described herein is a practical and convenient approach that enabled radical-mediated conjugate addition of unreactive alkenes to electron-deficient alkenes leading to a broad range of substituted malononitriles. These reactions are believed to proceed by Fe-catalysed hydrogen atom transfer (HAT) onto the alkenes affording carbon-centered radical intermediates with Markovnikov selectivity, followed by the capture of electron-deficient alkenes. We explored this synthesis approach under mild conditions with high efficiency and broad substrate scope and the utility is highlighted by the further synthetic transformations of the obtained substituted malononitriles.
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Affiliation(s)
- Tianxiang Zhu
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
| | - Xue-Jun Zhang
- Department of Orthopedic Surgery, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Zihan Zhou
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
| | - Zitong Xu
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
| | - Mengtao Ma
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
| | - Binlin Zhao
- Department of Chemistry and Materials Science, College of Science, Nanjing Forestry University, Nanjing 210037, China.
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56
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Fang X, Zhang N, Chen SC, Luo T. Scalable Total Synthesis of (-)-Triptonide: Serendipitous Discovery of a Visible-Light-Promoted Olefin Coupling Initiated by Metal-Catalyzed Hydrogen Atom Transfer (MHAT). J Am Chem Soc 2022; 144:2292-2300. [PMID: 35089705 DOI: 10.1021/jacs.1c12525] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
An efficient and scalable total synthesis of (-)-triptonide is accomplished based on a metal-catalyzed hydrogen atom transfer (MHAT)-initiated radical cyclization. During the optimization of the key step, we discovered that blue LEDs significantly promoted the efficiency of reaction initiated by Co(TPP)-catalyzed MHAT. Further exploration and optimization of this catalytic system led to development of a dehydrogenative MHAT-initiated Giese reaction.
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Affiliation(s)
- Xianhe Fang
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.,Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, Guangdong 518055, China
| | - Nan Zhang
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Si-Cong Chen
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Tuoping Luo
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.,Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.,Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, Guangdong 518055, China
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57
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Wein LA, Wurst K, Magauer T. Total Synthesis and Late-Stage C-H Oxidations of ent-Trachylobane Natural Products. Angew Chem Int Ed Engl 2022; 61:e202113829. [PMID: 34762359 PMCID: PMC7612322 DOI: 10.1002/anie.202113829] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Indexed: 11/23/2022]
Abstract
Herein, we present our studies to construct seven ent-trachylobane diterpenoids by employing a bioinspired two-phase synthetic strategy. The first phase provided enantioselective and scalable access to five ent-trachylobanes, of which methyl ent-trachyloban-19-oate was produced on a 300 mg scale. During the second phase, chemical C-H oxidation methods were employed to enable selective conversion to two naturally occurring higher functionalized ent-trachylobanes. The formation of regioisomeric analogs, which are currently inaccessible via enzymatic methods, reveals the potential as well as limitations of established chemical C-H oxidation protocols for complex molecule synthesis.
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Affiliation(s)
- Lukas Anton Wein
- Institute of Organic Chemistry and Center for Molecular BiosciencesLeopold-Franzens-University InnsbruckInnrain 80–826020InnsbruckAustria
| | - Klaus Wurst
- Institute of GeneralInorganic and Theoretical ChemistryLeopold-Franzens-University InnsbruckInnrain 80–826020InnsbruckAustria
| | - Thomas Magauer
- Institute of Organic Chemistry and Center for Molecular BiosciencesLeopold-Franzens-University InnsbruckInnrain 80–826020InnsbruckAustria
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58
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Wein LA, Wurst K, Magauer T. Total Synthesis and Late-Stage C-H Oxidations of ent-Trachylobane Natural Products. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 134:e202113829. [PMID: 38505342 PMCID: PMC10947344 DOI: 10.1002/ange.202113829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Indexed: 03/21/2024]
Abstract
Herein, we present our studies to construct seven ent-trachylobane diterpenoids by employing a bioinspired two-phase synthetic strategy. The first phase provided enantioselective and scalable access to five ent-trachylobanes, of which methyl ent-trachyloban-19-oate was produced on a 300 mg scale. During the second phase, chemical C-H oxidation methods were employed to enable selective conversion to two naturally occurring higher functionalized ent-trachylobanes. The formation of regioisomeric analogs, which are currently inaccessible via enzymatic methods, reveals the potential as well as limitations of established chemical C-H oxidation protocols for complex molecule synthesis.
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Affiliation(s)
- Lukas Anton Wein
- Institute of Organic Chemistry and Center for Molecular BiosciencesLeopold-Franzens-University InnsbruckInnrain 80–826020InnsbruckAustria
| | - Klaus Wurst
- Institute of GeneralInorganic and Theoretical ChemistryLeopold-Franzens-University InnsbruckInnrain 80–826020InnsbruckAustria
| | - Thomas Magauer
- Institute of Organic Chemistry and Center for Molecular BiosciencesLeopold-Franzens-University InnsbruckInnrain 80–826020InnsbruckAustria
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59
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Sun P, Zhang Z, Wang X, Li L, Li Y, Li Z. Cobalt‐catalyzed Intermolecular Hydroamination of Unactivated Alkenes Using
NFSI
as Nitrogen Source. CHINESE J CHEM 2022. [DOI: 10.1002/cjoc.202100827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Peng‐Wei Sun
- State Key Laboratory of Elemento‐Organic Chemistry, Research Institute of Elemento‐Organic Chemistry, College of Chemistry, Nankai University Tianjin 300071 China
| | - Ze Zhang
- State Key Laboratory of Elemento‐Organic Chemistry, Research Institute of Elemento‐Organic Chemistry, College of Chemistry, Nankai University Tianjin 300071 China
| | - Xinyao Wang
- State Key Laboratory of Elemento‐Organic Chemistry, Research Institute of Elemento‐Organic Chemistry, College of Chemistry, Nankai University Tianjin 300071 China
| | - Linshan Li
- State Key Laboratory of Elemento‐Organic Chemistry, Research Institute of Elemento‐Organic Chemistry, College of Chemistry, Nankai University Tianjin 300071 China
| | - Yuxin Li
- State Key Laboratory of Elemento‐Organic Chemistry, Research Institute of Elemento‐Organic Chemistry, College of Chemistry, Nankai University Tianjin 300071 China
| | - Zhengming Li
- State Key Laboratory of Elemento‐Organic Chemistry, Research Institute of Elemento‐Organic Chemistry, College of Chemistry, Nankai University Tianjin 300071 China
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60
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Qin Y, Zhou B, Tian D, An J, Zhou Y, Yan R, Song H, Liu XY. Co-catalyzed C(sp3)−C(sp2) bond cleavage via hydrogen atom transfer. Org Chem Front 2022. [DOI: 10.1039/d2qo00125j] [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
The discovery of a new Co-catalyzed hydrogen atom transfer (HAT) C(sp3)-C(sp2) bond cleavage method to access ketones from alkenes is reported. This unprecedented transformation features mild reaction conditions and good...
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61
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Maier MS, Shemet A, Trauner D. Assembling the carbon skeleton of A-74528. Chem Sci 2022; 13:8395-8400. [PMID: 35919712 PMCID: PMC9297437 DOI: 10.1039/d2sc01366e] [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: 03/08/2022] [Accepted: 06/23/2022] [Indexed: 11/21/2022] Open
Abstract
The 2′-phosphodiesterase inhibitor A-74528, which combines an intriguing biosynthesis with unusual biological activity, is one of the most complex type II polyketides. As a synthetic target, it represents a significant challenge due to its size but also due to a unique carbon skeleton that features a hexacarbocyclic core with an appended pyrone. Here we report our efforts toward the synthesis of A-74528, which culminated in the construction of the full carbon skeleton and the correct installation of all but one stereocenter. Our strategy employs a molybdenum-catalyzed branched allylation to establish the central quaternary carbon and relies on establishing the remaining stereocenters in a substrate-controlled manner. Carbocycles were established using a spiro epoxide annulation, a 1,3-dipolar cycloaddition, followed by an aldol condensation, and a gold-catalyzed hydroarylation. The pyrone was appended to an aldehyde branching off the quaternary stereocenter by a one-carbon homologation and Mukaiyama aldol addition. We report our efforts toward the synthesis of A-74528, which culminated in the construction of the full carbon skeleton.![]()
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Affiliation(s)
- Martin S. Maier
- Department of Chemistry, Ludwig Maximilian University of Munich, 81377 Munich, Germany
- Department of Chemistry, New York University, New York, New York 10003, USA
| | - Andrej Shemet
- Department of Chemistry, New York University, New York, New York 10003, USA
| | - Dirk Trauner
- Department of Chemistry, Ludwig Maximilian University of Munich, 81377 Munich, Germany
- Department of Chemistry, New York University, New York, New York 10003, USA
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62
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Jiang B, Dai M. 11-Step and Scalable Total Synthesis of Hamigeran M Enabled by Five C-H Functionalizations. J Am Chem Soc 2021; 143:20084-20089. [PMID: 34813320 DOI: 10.1021/jacs.1c11060] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report the convergent total synthesis of (±)-hamigeran M, enabled by five C-H functionalization reactions and proceeding in 11 steps in 3.9% overall yield. The C-H functionalizations include a hydroxy-directed C-H borylation, one C-H metalation-1,2-addition, one C-H metalation-Negishi coupling, a late-stage oxazole-directed C-H borylation-oxidation, and one electrophilic bromination. Two of these five C-H functionalizations forged strategic C-C bonds in the seven-membered ring of hamigeran M. The oxazole-directed C-H borylation-oxidation was unprecedented and ensured a late-stage hydroxylation. Other key steps include a tandem Suzuki reaction-lactonization to join the cyclopentane building block with the aromatic moiety and a hydrogen-atom transfer reaction to reduce a challenging tetrasubstituted double bond.
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Affiliation(s)
- Baiyang Jiang
- Department of Chemistry and Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
| | - Mingji Dai
- Department of Chemistry and Center for Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
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63
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Sang S, Unruh T, Demeshko S, Domenianni LI, van Leest NP, Marquetand P, Schneck F, Würtele C, de Zwart FJ, de Bruin B, González L, Vöhringer P, Schneider S. Photo-Initiated Cobalt-Catalyzed Radical Olefin Hydrogenation. Chemistry 2021; 27:16978-16989. [PMID: 34156122 PMCID: PMC9292329 DOI: 10.1002/chem.202101705] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Indexed: 11/30/2022]
Abstract
Outer‐sphere radical hydrogenation of olefins proceeds via stepwise hydrogen atom transfer (HAT) from transition metal hydride species to the substrate. Typical catalysts exhibit M−H bonds that are either too weak to efficiently activate H2 or too strong to reduce unactivated olefins. This contribution evaluates an alternative approach, that starts from a square‐planar cobalt(II) hydride complex. Photoactivation results in Co−H bond homolysis. The three‐coordinate cobalt(I) photoproduct binds H2 to give a dihydrogen complex, which is a strong hydrogen atom donor, enabling the stepwise hydrogenation of both styrenes and unactivated aliphatic olefins with H2 via HAT.
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Affiliation(s)
- Sier Sang
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, 37077, Göttingen, Germany
| | - Tobias Unruh
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstrasse 12, 53117, Bonn, Germany
| | - Serhiy Demeshko
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, 37077, Göttingen, Germany
| | - Luis I Domenianni
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstrasse 12, 53117, Bonn, Germany
| | - Nicolaas P van Leest
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Philipp Marquetand
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090, Vienna, Austria
| | - Felix Schneck
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, 37077, Göttingen, Germany
| | - Christian Würtele
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, 37077, Göttingen, Germany
| | - Felix J de Zwart
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Bas de Bruin
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Leticia González
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090, Vienna, Austria
| | - Peter Vöhringer
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstrasse 12, 53117, Bonn, Germany
| | - Sven Schneider
- Universität Göttingen, Institut für Anorganische Chemie, Tammannstraße 4, 37077, Göttingen, Germany
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64
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Márquez-Cadena MA, Zhang W, Tong R. Synthetic Studies toward the Berkeleyacetal Core Architecture. Org Lett 2021; 23:9227-9231. [PMID: 34780201 DOI: 10.1021/acs.orglett.1c03559] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Berkeleyacetals are structurally complex natural products that have shown potent anti-inflammatory activity. The presence of a highly dense oxygen functionality and a polycyclic ring system presents significant synthetic challenges. Herein, we report an efficient strategy for the construction of the tetracyclic core system of berkeleyacetal. Our synthetic strategy features two cycloadditions ([4+2] and [5+2]) to forge the tetracyclic core and Achmatowicz rearrangement for the preparation of the cyclization substrates containing B and E rings.
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Affiliation(s)
- Miguel Adrián Márquez-Cadena
- Department of Chemistry and Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong 999077, China
| | - Wei Zhang
- Department of Chemistry and Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong 999077, China
| | - Rongbiao Tong
- Department of Chemistry and Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong 999077, China
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65
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Sombret J, Quintaine J, Biremond T, Barnes Q, Saint‐Laumer J, Saudan L. High
trans
‐2‐Decalones by Photoredox Catalyzed β‐Isomerization. Helv Chim Acta 2021. [DOI: 10.1002/hlca.202100180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Juliette Sombret
- Synthesis & Process Engineering Research & Dev. Firmenich SA 7 rue de la Bergère CH-1242 Satigny, Geneva Switzerland
| | - Julie Quintaine
- Synthesis & Process Engineering Research & Dev. Firmenich SA 7 rue de la Bergère CH-1242 Satigny, Geneva Switzerland
| | - Tony Biremond
- Synthesis & Process Engineering Research & Dev. Firmenich SA 7 rue de la Bergère CH-1242 Satigny, Geneva Switzerland
| | - Quentin Barnes
- Synthesis & Process Engineering Research & Dev. Firmenich SA 7 rue de la Bergère CH-1242 Satigny, Geneva Switzerland
| | - Jean‐Yves Saint‐Laumer
- Synthesis & Process Engineering Research & Dev. Firmenich SA 7 rue de la Bergère CH-1242 Satigny, Geneva Switzerland
| | - Lionel Saudan
- Synthesis & Process Engineering Research & Dev. Firmenich SA 7 rue de la Bergère CH-1242 Satigny, Geneva Switzerland
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66
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Li N, Gui Y, Chu M, You M, Qiu X, Liu H, Wang S, Deng M, Ji B. Cobalt-Catalyzed Deprotection of Allyl Carboxylic Esters Induced by Hydrogen Atom Transfer. Org Lett 2021; 23:8460-8464. [PMID: 34670095 DOI: 10.1021/acs.orglett.1c03185] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A brief, efficient method has been developed for the removal of the allyl protecting group from allyl carboxylic esters using a Co(II)/TBHP/(Me2SiH)2O catalytic system. This facile strategy displays excellent chemoselectivity, functional group tolerance, and high yields. This transformation probably occurs through the hydrogen atom transfer process, and a Co(III)-six-membered cyclic intermediate is recommended.
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Affiliation(s)
- Nan Li
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
| | - Yizhen Gui
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
| | - Mengqi Chu
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
| | - Mengdi You
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
| | - Xiaohan Qiu
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
| | - Hejia Liu
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
| | - Shiang Wang
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
| | - Meng Deng
- Luoyang Key Laboratory of Organic Functional Molecules, College of Food and Drug, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
| | - Baoming Ji
- Henan Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang, Henan 471934, People's Republic of China
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67
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Visible light enables catalytic formation of weak chemical bonds with molecular hydrogen. Nat Chem 2021; 13:969-976. [PMID: 34253889 DOI: 10.1038/s41557-021-00732-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 05/13/2021] [Indexed: 02/08/2023]
Abstract
The synthesis of weak chemical bonds at or near thermodynamic potential is a fundamental challenge in chemistry, with applications ranging from catalysis to biology to energy science. Proton-coupled electron transfer using molecular hydrogen is an attractive strategy for synthesizing weak element-hydrogen bonds, but the intrinsic thermodynamics presents a challenge for reactivity. Here we describe the direct photocatalytic synthesis of extremely weak element-hydrogen bonds of metal amido and metal imido complexes, as well as organic compounds with bond dissociation free energies as low as 31 kcal mol-1. Key to this approach is the bifunctional behaviour of the chromophoric iridium hydride photocatalyst. Activation of molecular hydrogen occurs in the ground state and the resulting iridium hydride harvests visible light to enable spontaneous formation of weak chemical bonds near thermodynamic potential with no by-products. Photophysical and mechanistic studies corroborate radical-based reaction pathways and highlight the uniqueness of this photodriven approach in promoting new catalytic chemistry.
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68
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Song X, Wang R, Shi L, Luo T, Gao Z, Ren L, Zhou W, Hao H. Stereoselective Synthesis of Kalafungin Based on CuI‐Catalyzed Tandem Reactions of Arylethynes Containing an Ortho‐(1‐Hydroxyethyl) Substituent with Alkyl Diazoacetates. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202100589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Xiaoqing Song
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi 712100 People's Republic of China
| | - Ruizhi Wang
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi 712100 People's Republic of China
| | - Liang Shi
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi 712100 People's Republic of China
| | - Tianlong Luo
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi 712100 People's Republic of China
| | - Zhiyu Gao
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi 712100 People's Republic of China
| | - Li Ren
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi 712100 People's Republic of China
| | - Wenming Zhou
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi 712100 People's Republic of China
| | - Hong‐Dong Hao
- Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi 712100 People's Republic of China
- State Key Laboratory of Bioorganic & Natural Products Chemistry, Shanghai Institute of Organic Chemistry (SIOC) Chinese Academy of Science Shanghai 200032 People's Republic of China
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69
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Chen R, Qiu D, Lei X, Niu Y, Hua Y, Peng H, Zeng T, Zhang Y. Total Synthesis and Assignment of the Absolute Configuration of (+)-Omphalic Acid. Org Lett 2021; 23:6972-6976. [PMID: 34397211 DOI: 10.1021/acs.orglett.1c02599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Omphalane diterpenoids usually contain a cyclohexane-fused bicyclo[3.2.1]octane scaffold embedded with two continuous quaternary carbon centers, which pose considerable challenges to synthetic chemists. Herein, we reported the first total synthesis of omphalic acid with high stereochemical control, featuring an intermolecular Diels-Alder cycloaddition, ring reorganization through Criegee oxidative cleavage and programmed aldol condensations, conformationally controlled hydrogenation, and Pd-catalyzed carboxylation. The absolute configuration of omphalic acid was defined for the first time via the asymmetric total synthesis facilitated by a derivatization resolution protocol.
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Affiliation(s)
- Renzhi Chen
- Department of Chemistry, Department of Chemical Biology, and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Dongsheng Qiu
- Department of Chemistry, Department of Chemical Biology, and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Xin Lei
- Department of Chemistry, Department of Chemical Biology, and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Yujie Niu
- Department of Chemistry, Department of Chemical Biology, and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Yuhui Hua
- Department of Chemistry, Department of Chemical Biology, and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Huayu Peng
- Department of Chemistry, Department of Chemical Biology, and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Tao Zeng
- Department of Chemistry, Department of Chemical Biology, and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Yandong Zhang
- Department of Chemistry, Department of Chemical Biology, and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
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70
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Derosa J, Garrido-Barros P, Peters JC. Electrocatalytic Reduction of C-C π-Bonds via a Cobaltocene-Derived Concerted Proton-Electron Transfer Mediator: Fumarate Hydrogenation as a Model Study. J Am Chem Soc 2021; 143:9303-9307. [PMID: 34138550 DOI: 10.1021/jacs.1c03335] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Reductive concerted proton-electron transfer (CPET) is poorly developed for the reduction of C-C π-bonds, including for activated alkenes that can succumb to deleterious pathways (e.g., a competing hydrogen evolution reaction or oligomerization) in a standard electrochemical reduction. We demonstrate herein that selective hydrogenation of the C-C π-bond of fumarate esters can be achieved via electrocatalytic CPET (eCPET) using a CPET mediator comprising cobaltocene with a tethered Brønsted base. High selectivity for electrocatalytic hydrogenation is observed only when the mediator is present. Mechanistic analysis sheds light on two distinct kinetic regimes based on the substrate concentration: low fumarate concentrations operate via rate-limiting CPET followed by an electron-transfer/proton-transfer (ET/PT) step, whereas high concentrations operate via CPET followed by a rate-limiting ET/PT step.
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Affiliation(s)
- Joseph Derosa
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States
| | - Pablo Garrido-Barros
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States
| | - Jonas C Peters
- Division of Chemistry and Chemical Engineering, California Institute of Technology (Caltech), Pasadena, California 91125, United States
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71
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Gu Y, Norton JR, Salahi F, Lisnyak VG, Zhou Z, Snyder SA. Highly Selective Hydrogenation of C═C Bonds Catalyzed by a Rhodium Hydride. J Am Chem Soc 2021; 143:9657-9663. [PMID: 34142805 DOI: 10.1021/jacs.1c04683] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Under mild conditions (room temperature, 80 psi of H2) Cp*Rh(2-(2-pyridyl)phenyl)H catalyzes the selective hydrogenation of the C═C bond in α,β-unsaturated carbonyl compounds, including natural product precursors with bulky substituents in the β position and substrates possessing an array of additional functional groups. It also catalyzes the hydrogenation of many isolated double bonds. Mechanistic studies reveal that no radical intermediates are involved, and the catalyst appears to be homogeneous, thereby affording important complementarity to existing protocols for similar hydrogenation processes.
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Affiliation(s)
- Yiting Gu
- Department of Chemistry, Columbia University, 3000 Broadway, New York City, New York 10027, United States
| | - Jack R Norton
- Department of Chemistry, Columbia University, 3000 Broadway, New York City, New York 10027, United States
| | - Farbod Salahi
- Department of Chemistry, University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Vladislav G Lisnyak
- Department of Chemistry, University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Zhiyao Zhou
- Department of Chemistry, University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Scott A Snyder
- Department of Chemistry, University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
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72
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Abstract
The first total synthesis of (±)-jujuyane, a cyclooctanoid natural product, was accomplished from a (5 + 3) dimerization product of oxidopyrylium ylide that forms the cyclooctanoid core structure along with inherited stereochemical bias. Selective functional group modifications of the highly oxygenated dimeric structure, followed by the tactical functional group manipulation around the eight-membered carbocyclic core, enabled the total synthesis of (±)-jujuyane, which will serve a guide for future applications of oxidopyrylium dimers to the natural product total synthesis.
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Affiliation(s)
- Sanghyeon Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | | | | | - Jiheon Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Hee-Yoon Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
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73
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Zhu Y, He Y, Tian W, Wang M, Zhou Z, Song X, Ding H, Xiao Q. Dual Cobalt and Photoredox Catalysis Enabled Redox‐Neutral Annulation of 2‐Propynolphenols. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202100221] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Yao Zhu
- Institute of Organic Chemistry Jiangxi Science & Technology Normal University Key Laboratory of Organic Chemistry Jiangxi Province Nanchang 330013 People's Republic of China
| | - Yong‐Qin He
- School of Pharmaceutical Science Nanchang University Nanchang 330006 People's Republic of China
| | - Wan‐Fa Tian
- Institute of Organic Chemistry Jiangxi Science & Technology Normal University Key Laboratory of Organic Chemistry Jiangxi Province Nanchang 330013 People's Republic of China
| | - Mei Wang
- Institute of Organic Chemistry Jiangxi Science & Technology Normal University Key Laboratory of Organic Chemistry Jiangxi Province Nanchang 330013 People's Republic of China
| | - Zhao‐Zhao Zhou
- Department of Chemistry Nanchang Normal University Nanchang People's Republic of China
| | - Xian‐Rong Song
- Institute of Organic Chemistry Jiangxi Science & Technology Normal University Key Laboratory of Organic Chemistry Jiangxi Province Nanchang 330013 People's Republic of China
| | - Hai‐Xin Ding
- Institute of Organic Chemistry Jiangxi Science & Technology Normal University Key Laboratory of Organic Chemistry Jiangxi Province Nanchang 330013 People's Republic of China
| | - Qiang Xiao
- Institute of Organic Chemistry Jiangxi Science & Technology Normal University Key Laboratory of Organic Chemistry Jiangxi Province Nanchang 330013 People's Republic of China
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74
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Xin Z, Wang H, He H, Zhao X, Gao S. Asymmetric Total Synthesis of Norzoanthamine. Angew Chem Int Ed Engl 2021; 60:12807-12812. [PMID: 33822444 DOI: 10.1002/anie.202102643] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/26/2021] [Indexed: 11/08/2022]
Abstract
We report herein the asymmetric total synthesis of norzoanthamine using radical reactions as key steps for rapid access to the congested carbocyclic core, which is the major synthetic challenge for most zoanthamine alkaloids. (1) The Ueno-Stork radical cyclization was applied to construct the adjacent quaternary centers at the C-9 and C-22 positions; (2) a Co-catalyzed HAT radical reaction was successfully applied to construct the quaternary center at C-12 via Csp3 -Csp2 bond formation; (3) a Mn-catalyzed HAT radical reaction was used to stereospecifically reduce the tetra-substituted olefin (C13=C18) and install the contiguous stereocenters in proximity to the quaternary center. A one-pot bio-inspired cyclization step was finally applied to forge the unstable bis-amino acetal skeleton. Our approach can precisely control the stereochemistry of seven vicinal stereocenters and effectively construct the highly congested heptacyclic skeleton.
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Affiliation(s)
- Zhengyuan Xin
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, China
| | - Hui Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, 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
| | - Xiaoli Zhao
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes, School of Chemistry and Molecular Engineering, 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, 3663 North Zhongshan Road, Shanghai, 200062, 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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75
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Xin Z, Wang H, He H, Zhao X, Gao S. Asymmetric Total Synthesis of Norzoanthamine. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Zhengyuan Xin
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University 3663 North Zhongshan Road Shanghai 200062 China
| | - Hui Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering East China Normal University 3663 North Zhongshan Road Shanghai 200062 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
| | - Xiaoli Zhao
- Shanghai Key Laboratory of Green Chemistry and Chemical, Processes School of Chemistry and Molecular Engineering 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 3663 North Zhongshan Road Shanghai 200062 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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76
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Zhang B, He J, Li Y, Song T, Fang Y, Li C. Cobalt-Catalyzed Markovnikov-Selective Radical Hydroacylation of Unactivated Alkenes with Acylphosphonates. J Am Chem Soc 2021; 143:4955-4961. [PMID: 33783191 DOI: 10.1021/jacs.1c02629] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Acylphosphonates having the 5,5-dimethyl-1,3,2-dioxophosphinanyl skeleton are developed as efficient intermolecular radical acylation reagents, which enable the cobalt-catalyzed Markovnikov hydroacylation of unactivated alkenes at room temperature under mild conditions. The protocol exhibits broad substrate scope and wide functional group compatibility, providing branched ketones in satisfactory yields. A mechanism involving the Co-H mediated hydrogen atom transfer and subsequent trapping of alkyl radicals by acylphosphonates is proposed.
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Affiliation(s)
- Benxiang Zhang
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Jiayan He
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Yi Li
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Tao Song
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Yewen Fang
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China
| | - Chaozhong Li
- School of Materials and Chemical Engineering, Ningbo University of Technology, No. 201 Fenghua Road, Ningbo 315211, China.,Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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77
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Nakayama Y, Maser MR, Okita T, Dubrovskiy AV, Campbell TL, Reisman SE. Total Synthesis of Ritterazine B. J Am Chem Soc 2021; 143:4187-4192. [PMID: 33689345 DOI: 10.1021/jacs.1c01372] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The first total synthesis of the cytotoxic alkaloid ritterazine B is reported. The synthesis features a unified approach to both steroid subunits, employing a titanium-mediated propargylation reaction to achieve divergence from a common precursor. Other key steps include gold-catalyzed cycloisomerizations that install both spiroketals and late stage C-H oxidation to incorporate the C7' alcohol.
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Affiliation(s)
- Yasuaki Nakayama
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Michael R Maser
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Tatsuya Okita
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Anton V Dubrovskiy
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Taryn L Campbell
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Sarah E Reisman
- The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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78
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Abstract
AbstractHydrogen atom transfer (HAT) is one of the fundamental transformations of organic chemistry, allowing the interconversion of open- and closed-shell species through the concerted movement of a proton and an electron. Although the value of this transformation is well appreciated in isolation, with it being used for homolytic C–H activation via abstractive HAT and radical reduction via donative HAT, cooperative HAT (cHAT) reactions, in which two hydrogen atoms are removed or donated to vicinal reaction centers in succession through radical intermediates, are comparatively unknown outside of the mechanism of desaturase enzymes. This tandem reaction scheme has important ramifications in the thermochemistry of each HAT, with the bond dissociation energy (BDE) of the C–H bond adjacent to the radical center being significantly lowered relative to that of the parent alkane, allowing each HAT to be performed by different species. Herein, we discuss the thermodynamic basis of this bond strength differential in cHAT and demonstrate its use as a design principle in organic chemistry for both dehydrogenative (application 1) and hydrogenative (application 2) reactions. We hope that this overview will highlight the exciting reactivity that is possible with cHAT and inspire further developments with this mechanistic approach.1 Introduction and Theory2 Application: Dehydrogenative Transformations3 Application: Alkene Hydrogenation4 Future Applications of cHAT
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79
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Simlandy AK, Sardini SR, Brown MK. Construction of congested Csp 3-Csp 3 bonds by a formal Ni-catalyzed alkylboration. Chem Sci 2021; 12:5517-5521. [PMID: 34168789 PMCID: PMC8179681 DOI: 10.1039/d1sc00900a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Through the combination of a Ni-catalyzed alkene alkenylboration followed by hydrogenation, the synthesis of congested Csp3–Csp3-bonds can be achieved. Conditions have been identified that allow for the use of both alkenyl-bromides and -triflates. In addition, the hydrogenation creates another opportunity for stereocontrol, thus allowing access to multiple stereoisomers of the product. Finally, the method is demonstrated in the streamlined synthesis of a biologically relevant molecule. Through the combination of a Ni-catalyzed alkene alkenylboration followed by hydrogenation, the synthesis of congested Csp3–Csp3-bonds can be achieved.![]()
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Affiliation(s)
- Amit Kumar Simlandy
- Department of Chemistry, Indiana University 800E. Kirkwood Ave Bloomington IN 47401 USA
| | - Stephen R Sardini
- Department of Chemistry, Indiana University 800E. Kirkwood Ave Bloomington IN 47401 USA
| | - M Kevin Brown
- Department of Chemistry, Indiana University 800E. Kirkwood Ave Bloomington IN 47401 USA
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80
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Abstract
Retrosynthetic analysis emerged in the 1960s as a teaching tool with profound implications. Its educational value can be appreciated by a glance at total synthesis manuscripts over 50 years later, most of which contain a retrosynthesis on page one. Its vision extended to computer language-a pioneering idea in the 20th century that continues to expand the frontiers today. The same principles that guide a student to evaluate, expand, and refine a series of bond dissections can be programmed, so that computer assistance can perform the same tasks but at faster speeds.The slow step in the synthesis of complex structures, however, is seldom route design. Compression of molecular information into close proximity (Cm/Å3) requires exploration and empiricism, a close connection between theory and experiment. Here, retrosynthetic analysis guides the choice of experiment, so that the most simplifying-but often least assured-disconnection is prioritized: a high-risk, high reward strategy. The reimagining of total synthesis in a future era of retrosynthetic software may involve, counterintuitively, target design, as discussed here.Compared to the 1960s, retrosynthetic analysis in the 21st century finds itself among computers of unimaginable power and a biology that is increasingly molecular. Put together, the logic of retrosynthesis, the insight of structural biology, and the predictions of computation have inspired us to imagine an integration of the three. The synthetic target is treated as dynamic-a constellation of related structures-in order to find the nearest congener with the closest affinity but the shortest synthetic route. Such an approach merges synthetic design with structural design toward the goal of improved access for improved function.In this Account, we detail the evolution of our program from its inception in traditional natural product (NP) total synthesis to its current expression through the lens of chemical informatics: a view of NPs as aggregates of molecular parameters that define single points in a chemical space. Early work on synthesis and biological annotation of apparent metal pool binders and nonselective covalent electrophiles (asmarine alkaloids, isocyanoterpenes, Nuphar dimers) gave way to NPs with well-defined protein targets. The plant metabolite salvinorin A (SalA) potently and selectively agonizes the κ-opioid receptor (KOR), rapidly penetrates the brain, and represents an important lead for next-generation analgesics and antipruritics. To synthesize and diversify this lead, we adopted what we now call a dynamic approach. Deletion of a central methyl group stabilized the SalA scaffold, opened quick synthetic access, and retained high potency and selectivity. The generality of this idea was then tested against another neuroactive class. As an alternative hypothesis to TrkB channels, we proposed that the so-called "neurotrophic" Illicium terpenes may bind to γ-aminobutyric acid (GABA)-gated ion channels to cause weak, chronic excitation. Syntheses of (-)-jiadifenolide, 3,6-dideoxy-10-hydroxypseudoanisatin, (-)-11-O-debenzoyltashironin, (-)-bilobalide, and (-)-picrotoxinin (PXN) allowed this hypothesis to be probed more broadly. Feedback from protein structure and synthetic reconnaissance led to a dynamic retrosynthesis of PXN and the identification of 5MePXN, a moderate GABAAR antagonist with greater aqueous stability available in eight steps from dimethylcarvone. We expect this dynamic approach to synthetic target analysis to become more feasible in the coming years and hope the next generation of scientists finds this approach helpful to address problems at the frontier of chemistry and biology.
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Affiliation(s)
- Stone Woo
- Department of Chemistry, Scripps Research, 10550 North Torrey Lines Road, La Jolla, California 92037, United States
| | - Ryan A Shenvi
- Department of Chemistry, Scripps Research, 10550 North Torrey Lines Road, La Jolla, California 92037, United States
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81
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Chen P, Wang C, Yang R, Xu H, Wu J, Jiang H, Chen K, Ma Z. Asymmetric Total Synthesis of Dankasterones A and B and Periconiastone A Through Radical Cyclization. Angew Chem Int Ed Engl 2021; 60:5512-5518. [PMID: 33206427 DOI: 10.1002/anie.202013881] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Indexed: 12/11/2022]
Abstract
We describe herein the assembly of the cis-decalin framework through radical cyclization initiated by metal-catalyzed hydrogen atom transfer (MHAT), further applied it in the asymmetric synthesis of dankasterones A and B and periconiastone A. Position-selective C-H oxygenation allowed for installation of the necessary functionality. A radical rearrangement was adopted to create 13(14→8)abeo-8-ergostane skeleton. Interconversion of dankasterone B and periconiastone A was realized through biomimetic intramolecular aldol and retro-aldol reactions. The MHAT-based approach, serves as a new dissection means, is complementary to the conventional ways to establish cis-decalin framework.
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Affiliation(s)
- Pengquan Chen
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Cheng Wang
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Rui Yang
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Hongjin Xu
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Jinghua Wu
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Huanfeng Jiang
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
| | - Kai Chen
- College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, China.,Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Zhiqiang Ma
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou, 510641, China
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82
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Kamei Y, Seino Y, Yamaguchi Y, Yoshino T, Maeda S, Kojima M, Matsunaga S. Silane- and peroxide-free hydrogen atom transfer hydrogenation using ascorbic acid and cobalt-photoredox dual catalysis. Nat Commun 2021; 12:966. [PMID: 33574227 PMCID: PMC7878493 DOI: 10.1038/s41467-020-20872-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 12/16/2020] [Indexed: 11/09/2022] Open
Abstract
Hydrogen atom transfer (HAT) hydrogenation has recently emerged as an indispensable method for the chemoselective reduction of unactivated alkenes. However, the hitherto reported systems basically require stoichiometric amounts of silanes and peroxides, which prevents wider applications, especially with respect to sustainability and safety concerns. Herein, we report a silane- and peroxide-free HAT hydrogenation using a combined cobalt/photoredox catalysis and ascorbic acid (vitamin C) as a sole stoichiometric reactant. A cobalt salophen complex is identified as the optimal cocatalyst for this environmentally benign HAT hydrogenation in aqueous media, which exhibits high functional-group tolerance. In addition to its applicability in the late-stage hydrogenation of amino-acid derivatives and drug molecules, this method offers unique advantage in direct transformation of unprotected sugar derivatives and allows the HAT hydrogenation of unprotected C-glycoside in higher yield compared to previously reported HAT hydrogenation protocols. The proposed mechanism is supported by experimental and theoretical studies.
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Affiliation(s)
- Yuji Kamei
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Yusuke Seino
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Yuto Yamaguchi
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Tatsuhiko Yoshino
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan
| | - Satoshi Maeda
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, 001-0021, Japan
- Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan
- JST, ERATO Maeda Artificial Intelligence for Chemical Reaction Design and Discovery Project, Sapporo, 060-0810, Japan
| | - Masahiro Kojima
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan.
| | - Shigeki Matsunaga
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, 060-0812, Japan.
- Global Station for Biosurfaces and Drug Discovery, Hokkaido University, Sapporo, 060-0812, Japan.
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83
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Kim Y, Sengupta S, Sim T. Natural and Synthetic Lactones Possessing Antitumor Activities. Int J Mol Sci 2021; 22:ijms22031052. [PMID: 33494352 PMCID: PMC7865919 DOI: 10.3390/ijms22031052] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 12/29/2022] Open
Abstract
Cancer is one of the leading causes of death globally, accounting for an estimated 8 million deaths each year. As a result, there have been urgent unmet medical needs to discover novel oncology drugs. Natural and synthetic lactones have a broad spectrum of biological uses including anti-tumor, anti-helminthic, anti-microbial, and anti-inflammatory activities. Particularly, several natural and synthetic lactones have emerged as anti-cancer agents over the past decades. In this review, we address natural and synthetic lactones focusing on their anti-tumor activities and synthetic routes. Moreover, we aim to highlight our journey towards chemical modification and biological evaluation of a resorcylic acid lactone, L-783277 (4). We anticipate that utilization of the natural and synthetic lactones as novel scaffolds would benefit the process of oncology drug discovery campaigns based on natural products.
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Affiliation(s)
- Younghoon Kim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea;
- Severance Biomedical Science Institute, Graduate School of Medical Science (Brain Korea 21 Project), College of Medicine, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea;
| | - Sandip Sengupta
- Severance Biomedical Science Institute, Graduate School of Medical Science (Brain Korea 21 Project), College of Medicine, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea;
| | - Taebo Sim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea;
- Severance Biomedical Science Institute, Graduate School of Medical Science (Brain Korea 21 Project), College of Medicine, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea;
- Correspondence: ; Tel.: +82-2-2228-0797
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84
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Mendelsohn LN, MacNeil CS, Tian L, Park Y, Scholes GD, Chirik PJ. Visible-Light-Enhanced Cobalt-Catalyzed Hydrogenation: Switchable Catalysis Enabled by Divergence between Thermal and Photochemical Pathways. ACS Catal 2021. [DOI: 10.1021/acscatal.0c05136] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Lauren N. Mendelsohn
- Department of Chemistry, Frick Chemistry Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Connor S. MacNeil
- Department of Chemistry, Frick Chemistry Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Lei Tian
- Department of Chemistry, Frick Chemistry Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Yoonsu Park
- Department of Chemistry, Frick Chemistry Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Gregory D. Scholes
- Department of Chemistry, Frick Chemistry Laboratory, Princeton University, Princeton, New Jersey 08544, United States
| | - Paul J. Chirik
- Department of Chemistry, Frick Chemistry Laboratory, Princeton University, Princeton, New Jersey 08544, United States
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85
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Enomoto M. Recent advances in the total syntheses of indole diterpenoids. Biosci Biotechnol Biochem 2021; 85:13-23. [DOI: 10.1093/bbb/zbaa061] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 09/22/2020] [Indexed: 12/21/2022]
Abstract
Abstract
Indole diterpenoids constitute a large family of natural products that are characterized by a hybrid molecular architecture consisting of an indole nucleus and diterpenoid moiety. Their pharmacologically and agriculturally important biological properties as well as intriguing molecular architectures have attracted much attention from many synthetic organic chemists. In 2012, we succeeded in the concise total synthesis of a paspalane-type indole diterpenoid, namely paspalinine, by developing a highly efficient indole ring formation protocol. After the report of this total synthesis, 4 research groups achieved the total syntheses of other paspalane- and nodulisporane-type indole diterpenoids using current state-of-the-art methods. This review summarizes the total syntheses of the paspalane- and nodulisporane-type indole diterpenoids that were described in the last 10 years.
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Affiliation(s)
- Masaru Enomoto
- Graduate School of Agricultural Science, Tohoku University, Aramaki Aza-Aoba, Aoba-ku, Sendai, Japan
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86
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Chen P, Wang C, Yang R, Xu H, Wu J, Jiang H, Chen K, Ma Z. Asymmetric Total Synthesis of Dankasterones A and B and Periconiastone A Through Radical Cyclization. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202013881] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Pengquan Chen
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Cheng Wang
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Rui Yang
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Hongjin Xu
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Jinghua Wu
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Huanfeng Jiang
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
| | - Kai Chen
- College of Chemistry and Chemical Engineering Central South University Changsha 410083 China
- Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen 518055 China
| | - Zhiqiang Ma
- Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry & Chemical Engineering South China University of Technology Wushan Road-381 Guangzhou 510641 China
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87
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Senapati BK. Recent progress in the synthesis of the furanosteroid family of natural products. Org Chem Front 2021. [DOI: 10.1039/d0qo01454k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review focuses on an overview of recent advances in the synthesis of furanosteroids and illustrates their applications in medicinal chemistry over the period of 2005–present.
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88
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Wu J, Ma Z. Metal-hydride hydrogen atom transfer (MHAT) reactions in natural product synthesis. Org Chem Front 2021. [DOI: 10.1039/d1qo01139a] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Functionalization of olefins has been an important transformation in synthetic chemistry. This review will focus on the natural product synthesis employing the MHAT reaction as the key strategy.
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Affiliation(s)
- Jinghua Wu
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou 510641, People's Republic of China
| | - Zhiqiang Ma
- Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry & Chemical Engineering, South China University of Technology, Wushan Road-381, Guangzhou 510641, People's Republic of China
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89
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Iyer RN, Favela D, Zhang G, Olson DE. The iboga enigma: the chemistry and neuropharmacology of iboga alkaloids and related analogs. Nat Prod Rep 2021; 38:307-329. [PMID: 32794540 DOI: 10.1039/d0np00033g] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Covering: 2000 up to 2020 Few classes of natural products have inspired as many chemists and biologists as have the iboga alkaloids. This family of monoterpenoid indole alkaloids includes the anti-addictive compound ibogaine as well as catharanthine, a precursor to the chemotherapeutic vinblastine. Despite being known for over 120 years, these small molecules continue to challenge our assumptions about biosynthetic pathways, catalyze our creativity for constructing complex architectures, and embolden new approaches for treating mental illness. This review will cover recent advances in both the biosynthesis and chemical synthesis of iboga alkaloids as well as their use as next-generation neurotherapeutics. Whenever appropriate, we provide historical context for the discoveries of the past decade and indicate areas that have yet to be resolved. While significant progress regarding their chemistry and pharmacology has been made since the 1960s, it is clear that the iboga alkaloids will continue to stoke scientific innovation for years to come.
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Affiliation(s)
- Rishab N Iyer
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - David Favela
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - Guoliang Zhang
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - David E Olson
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA. and Department of Biochemistry & Molecular Medicine, School of Medicine, University of California, Davis, 2700 Stockton Blvd, Suite 2102, Sacramento, CA 95817, USA and Center for Neuroscience, University of California, Davis, 1544 Newton Ct, Davis, CA 95618, USA
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90
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Zhang H, Wang B, Xu H, Li FY, Wang JY. Synthesis of naphthodihydrofurans via an iron( iii)-catalyzed reduction radical cascade reaction. Org Chem Front 2021. [DOI: 10.1039/d1qo01041g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A convenient method for the synthesis of naphthodihydrofurans has been developed by iron(iii)-catalyzed cascade reaction of reducing radicals.
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Affiliation(s)
- Hua Zhang
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Bei Wang
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Hong Xu
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Fu-Yu Li
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Ji-Yu Wang
- Department of Chemistry, Xihua University, P. R. China
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
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91
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Luo J, Rauch M, Avram L, Ben-David Y, Milstein D. Catalytic Hydrogenation of Thioesters, Thiocarbamates, and Thioamides. J Am Chem Soc 2020; 142:21628-21633. [PMID: 33332968 PMCID: PMC7775745 DOI: 10.1021/jacs.0c10884] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Direct hydrogenation of thioesters with H2 provides a facile and waste-free method to access alcohols and thiols. However, no report of this reaction is documented, possibly because of the incompatibility of the generated thiol with typical hydrogenation catalysts. Here, we report an efficient and selective hydrogenation of thioesters. The reaction is catalyzed by an acridine-based ruthenium complex without additives. Various thioesters were fully hydrogenated to the corresponding alcohols and thiols with excellent tolerance for amide, ester, and carboxylic acid groups. Thiocarbamates and thioamides also undergo hydrogenation under similar conditions, substantially extending the application of hydrogenation of organosulfur compounds.
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92
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Yang L, Wurm T, Sharma Poudel B, Krische MJ. Enantioselective Total Synthesis of Andrographolide and 14-Hydroxy-Colladonin: Carbonyl Reductive Coupling and trans-Decalin Formation by Hydrogen Transfer. Angew Chem Int Ed Engl 2020; 59:23169-23173. [PMID: 32896046 PMCID: PMC7920188 DOI: 10.1002/anie.202011363] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Indexed: 12/11/2022]
Abstract
An enantioselective total synthesis of the labdane diterpene andrographolide, the bitter principle of the herb Andrographis paniculata (known as "King of Bitters"), was accomplished in 14 steps (LLS). Key transformations include iridium-catalyzed carbonyl reductive coupling to form the quaternary C4 stereocenter, diastereoselective alkene reduction to establish the trans-decalin ring, and carbonylative lactonization to install the α-alkylidene-β-hydroxy-γ-butyrolactone.
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Affiliation(s)
| | | | | | - 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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93
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Zhang H, Zhang GM, He S, Shi ZC, Zhang XM, Wang JY. A Construction of α-Alkenyl Lactones via Reduction Radical Cascade Reaction of Allyl Alcohols and Acetylenic Acids. Org Lett 2020; 22:8337-8344. [PMID: 33040535 DOI: 10.1021/acs.orglett.0c02973] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An iron-catalyzed cascade reaction of radical reduction of allyl alcohols and acetylenic acids to construct polysubstituted α-alkenyl lactones has been developed. In this paper, various allyl alcohols can form allyl ester intermediates and are further transformed into alkyl radicals, which form products through intramolecular reflex-Michael addition. In addition, this method can be used to prepare spirocycloalkenyl lactones. Interestingly, this protocol can be used to synthesize the skeleton structure of natural products. Moreover, the product can be further transformed into a β-methylene tetrahydrofuran and tetrahydrofuran diene.
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Affiliation(s)
- Hua Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Guo-Min Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China.,University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Shuai He
- Southwest Minzu University, Chengdu 610041, P. R. China
| | | | - Xiao-Mei Zhang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
| | - Ji-Yu Wang
- Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, P. R. China
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94
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Abstract
Cyclohexane-angularly-fused triquinanes, 6-5-5-5 tetracycles, have attracted the attention of synthetic chemists due to their highly congested core structures and multiple quaternary carbon centers. This review focuses on the six completed total synthesis of naturally occurring cyclohexane-angularly-fused triquinanes in addition to seven notable methodologies that have been developed for the synthesis of these structures.
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Affiliation(s)
- Hongjun Jeon
- Department of Chemistry, University of Pennsylvania, 231 S. 34 Street, Philadelphia, PA 19104-6323, USA
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, 34114, Korea
| | - Jeffrey D Winkler
- Department of Chemistry, University of Pennsylvania, 231 S. 34 Street, Philadelphia, PA 19104-6323, USA
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95
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Kattamuri PV, West JG. Hydrogenation of Alkenes via Cooperative Hydrogen Atom Transfer. J Am Chem Soc 2020; 142:19316-19326. [PMID: 33119986 DOI: 10.1021/jacs.0c09544] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Radical hydrogenation via hydrogen atom transfer (HAT) to alkenes is an increasingly important transformation for the formation of thermodynamic alkane isomers. Current single-catalyst methods require stoichiometric oxidant in addition to hydride (H-) source to function. Here we report a new approach to radical hydrogenation: cooperative hydrogen atom transfer (cHAT), where each hydrogen atom donated to the alkene arrives from a different catalyst. Further, these hydrogen atom (H•) equivalents are generated from complementary hydrogen atom precursors, with each alkane requiring one hydride (H-) and one proton (H+) equivalent and no added oxidants. Preliminary mechanistic study supports this reaction manifold and shows the intersection of metal-catalyzed HAT and thiol radical trapping HAT catalytic cycles to be essential for effective catalysis. Together, this unique catalyst system allows us to reduce a variety of unactivated alkene substrates to their respective alkanes in high yields and diastereoselectivities and introduces a new approach to radical hydrogenation.
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Affiliation(s)
- Padmanabha V Kattamuri
- Department of Chemistry, Rice University, BioScience Research Collaborative, Houston, Texas 77030, United States
| | - Julian G West
- Department of Chemistry, Rice University, BioScience Research Collaborative, Houston, Texas 77030, United States
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96
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Demoret RM, Baker MA, Ohtawa M, Chen S, Lam CC, Khom S, Roberto M, Forli S, Houk KN, Shenvi RA. Synthetic, Mechanistic, and Biological Interrogation of Ginkgo biloba Chemical Space En Route to (-)-Bilobalide. J Am Chem Soc 2020; 142:18599-18618. [PMID: 32991152 PMCID: PMC7727090 DOI: 10.1021/jacs.0c08231] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Here we interrogate the structurally dense (1.64 mcbits/Å3) GABAA receptor antagonist bilobalide, intermediates en route to its synthesis, and related mechanistic questions. 13C isotope labeling identifies an unexpected bromine migration en route to an α-selective, catalytic asymmetric Reformatsky reaction, ruling out an asymmetric allylation pathway. Experiment and computation converge on the driving forces behind two surprising observations. First, an oxetane acetal persists in concentrated mineral acid (1.5 M DCl in THF-d8/D2O); its longevity is correlated to destabilizing steric clash between substituents upon ring-opening. Second, a regioselective oxidation of des-hydroxybilobalide is found to rely on lactone acidification through lone-pair delocalization, which leads to extremely rapid intermolecular enolate equilibration. We also establish equivalent effects of (-)-bilobalide and the nonconvulsive sesquiterpene (-)-jiadifenolide on action potential-independent inhibitory currents at GABAergic synapses, using (+)-bilobalide as a negative control. The high information density of bilobalide distinguishes it from other scaffolds and may characterize natural product (NP) space more generally. Therefore, we also include a Python script to quickly (ca. 132 000 molecules/min) calculate information content (Böttcher scores), which may prove helpful to identify important features of NP space.
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Affiliation(s)
- Robert M. Demoret
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Meghan A. Baker
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Masaki Ohtawa
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Shuming Chen
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Ching Ching Lam
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Sophia Khom
- Departments of Molecular Medicine and Neuroscience, La Jolla, California 92037, United States
| | - Marisa Roberto
- Departments of Molecular Medicine and Neuroscience, La Jolla, California 92037, United States
| | - Stefano Forli
- DISCoBio, Scripps Research, La Jolla, California 92037, United States
| | - Kendall N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Ryan A. Shenvi
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
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97
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Yang L, Wurm T, Sharma Poudel B, Krische MJ. Enantioselective Total Synthesis of Andrographolide and 14‐Hydroxy‐Colladonin: Carbonyl Reductive Coupling and
trans
‐Decalin Formation by Hydrogen Transfer. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202011363] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Lin Yang
- University of Texas at Austin Department of Chemistry 105 E 24th Street (A5300) Austin TX 78712-1167 USA
| | - Thomas Wurm
- University of Texas at Austin Department of Chemistry 105 E 24th Street (A5300) Austin TX 78712-1167 USA
| | - Binit Sharma Poudel
- University of Texas at Austin Department of Chemistry 105 E 24th Street (A5300) Austin TX 78712-1167 USA
| | - Michael J. Krische
- University of Texas at Austin Department of Chemistry 105 E 24th Street (A5300) Austin TX 78712-1167 USA
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98
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Chi HM, Cole CJF, Hu P, Taylor CA, Snyder SA. Total syntheses of spiroviolene and spirograterpene A: a structural reassignment with biosynthetic implications. Chem Sci 2020; 11:10939-10944. [PMID: 34094343 PMCID: PMC8162393 DOI: 10.1039/d0sc04686h] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 09/26/2020] [Indexed: 01/01/2023] Open
Abstract
The recent natural product isolates spiroviolene and spirograterpene A are two relatively non-functionalized linear triquinane terpenes with a large number of structural homologies. Nevertheless, three significant areas of structural disparity exist based on their original assignments, one of which implies a key stereochemical divergence early in their respective biosyntheses. Herein, using two known bicyclic ketone intermediates, a core Pd-catalyzed Heck cyclization sequence, and several chemoselective transformations, we describe concise total syntheses of both natural product targets and propose that the structure of spiroviolene should be reassigned. As a result, these natural products possess greater homology than previously anticipated.
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Affiliation(s)
- Hyung Min Chi
- Department of Chemistry, University of Chicago 5735 S. Ellis Avenue Chicago IL 60637 USA
| | - Charles J F Cole
- Department of Chemistry, University of Chicago 5735 S. Ellis Avenue Chicago IL 60637 USA
| | - Pengfei Hu
- Department of Chemistry, University of Chicago 5735 S. Ellis Avenue Chicago IL 60637 USA
| | - Cooper A Taylor
- Department of Chemistry, University of Chicago 5735 S. Ellis Avenue Chicago IL 60637 USA
| | - Scott A Snyder
- Department of Chemistry, University of Chicago 5735 S. Ellis Avenue Chicago IL 60637 USA
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99
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Shevick SL, Wilson CV, Kotesova S, Kim D, Holland PL, Shenvi RA. Catalytic hydrogen atom transfer to alkenes: a roadmap for metal hydrides and radicals. Chem Sci 2020; 11:12401-12422. [PMID: 33520153 PMCID: PMC7810138 DOI: 10.1039/d0sc04112b] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 09/28/2020] [Indexed: 12/12/2022] Open
Abstract
Hydrogen atom transfer from metal hydrides to alkenes appears to underlie widely used catalytic methods – the mechanistic implications are fascinating.
Hydrogen atom transfer from a metal hydride (MHAT) has emerged as a powerful, if puzzling, technique in chemical synthesis. In catalytic MHAT reactions, earth-abundant metal complexes generate stabilized and unstabilized carbon-centered radicals from alkenes of various substitution patterns with robust chemoselectivity. This perspective combines organic and inorganic perspectives to outline challenges and opportunities, and to propose working models to assist further developments. We attempt to demystify the putative intermediates, the basic elementary steps, and the energetic implications, especially for cage pair formation, collapse and separation. Distinctions between catalysts with strong-field (SF) and weak-field (WF) ligand environments may explain some differences in reactivity and selectivity, and provide an organizing principle for kinetics that transcends the typical thermodynamic analysis. This blueprint should aid practitioners who hope to enter and expand this exciting area of chemistry.
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Affiliation(s)
- Sophia L Shevick
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , CA 92037 , USA
| | - Conner V Wilson
- Department of Chemistry , Yale University , 225 Prospect St. , New Haven , CT 06511 , USA
| | - Simona Kotesova
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , CA 92037 , USA
| | - Dongyoung Kim
- Department of Chemistry , Yale University , 225 Prospect St. , New Haven , CT 06511 , USA
| | - Patrick L Holland
- Department of Chemistry , Yale University , 225 Prospect St. , New Haven , CT 06511 , USA
| | - Ryan A Shenvi
- Department of Chemistry , Scripps Research , 10550 North Torrey Pines Road , La Jolla , CA 92037 , USA
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100
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Eggert A, Etling C, Lübken D, Saxarra M, Kalesse M. Contiguous Quaternary Carbons: A Selection of Total Syntheses. Molecules 2020; 25:molecules25173841. [PMID: 32847075 PMCID: PMC7504199 DOI: 10.3390/molecules25173841] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 08/14/2020] [Accepted: 08/18/2020] [Indexed: 12/11/2022] Open
Abstract
Contiguous quaternary carbons in terpene natural products remain a major challenge in total synthesis. Synthetic strategies to overcome this challenge will be a pivotal prerequisite to the medicinal application of natural products and their analogs or derivatives. In this review, we cover syntheses of natural products that exhibit a dense assembly of quaternary carbons and whose syntheses were uncompleted until recently. While discussing their syntheses, we not only cover the most recent total syntheses but also provide an update on the status quo of modern syntheses of complex natural products. Herein, we review (±)-canataxpropellane, (+)-waihoensene, (–)-illisimonin A and (±)-11-O-debenzoyltashironin as prominent examples of natural products bearing contiguous quaternary carbons.
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Affiliation(s)
- Alina Eggert
- Institut für Organische Chemie, Gottfried Wilhelm Leibniz University Hannover und Biomolekulares Wirkstoffzentrum (BMWZ), Schneiderberg 1B, D-30167 Hannover, Germany; (A.E.); (C.E.); (D.L.); (M.S.)
| | - Christoph Etling
- Institut für Organische Chemie, Gottfried Wilhelm Leibniz University Hannover und Biomolekulares Wirkstoffzentrum (BMWZ), Schneiderberg 1B, D-30167 Hannover, Germany; (A.E.); (C.E.); (D.L.); (M.S.)
| | - Dennis Lübken
- Institut für Organische Chemie, Gottfried Wilhelm Leibniz University Hannover und Biomolekulares Wirkstoffzentrum (BMWZ), Schneiderberg 1B, D-30167 Hannover, Germany; (A.E.); (C.E.); (D.L.); (M.S.)
- Helmholtz Zentrum für Infektionsforschung(HZI), Inhoffenstraße 7, D-38124 Braunschweig, Germany
| | - Marius Saxarra
- Institut für Organische Chemie, Gottfried Wilhelm Leibniz University Hannover und Biomolekulares Wirkstoffzentrum (BMWZ), Schneiderberg 1B, D-30167 Hannover, Germany; (A.E.); (C.E.); (D.L.); (M.S.)
| | - Markus Kalesse
- Institut für Organische Chemie, Gottfried Wilhelm Leibniz University Hannover und Biomolekulares Wirkstoffzentrum (BMWZ), Schneiderberg 1B, D-30167 Hannover, Germany; (A.E.); (C.E.); (D.L.); (M.S.)
- Helmholtz Zentrum für Infektionsforschung(HZI), Inhoffenstraße 7, D-38124 Braunschweig, Germany
- Correspondence: ; Tel.: +49-(0)511-7624688
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