1
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Luo J, Upshur MA, Vega M, Doering NA, Varelas J, Ren Z, Geiger FM, Sarpong R, Thomson RJ. Strategies and Tactics for Site Specific Deuterium Incorporation at Each Available Carbon Atom of α-Pinene. J Org Chem 2024; 89:14265-14278. [PMID: 39306764 DOI: 10.1021/acs.joc.4c01702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2024]
Abstract
The development of several unique strategies and tactics for the synthesis of α-pinene isotopologues that has culminated in access to all eight possible isomers with deuterium incorporated selectively at each available carbon atom is described. Access to this library of isotopologues provides new tools to more fully investigate the atmospheric autoxidation of α-pinene, a complex process that plays a major role in the formation of secondary organic aerosol in the Earth's atmosphere.
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Affiliation(s)
- Jingyi Luo
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Mary Alice Upshur
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Marvin Vega
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Nicolle A Doering
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Jonathan Varelas
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Zhouyang Ren
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Franz M Geiger
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Richmond Sarpong
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Regan J Thomson
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
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2
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Cao Z, Sun W, Zhang J, Zhuo J, Yang S, Song X, Ma Y, Lu P, Han T, Li C. Total syntheses of (-)-macrocalyxoformins A and B and (-)-ludongnin C. Nat Commun 2024; 15:6052. [PMID: 39025872 PMCID: PMC11258297 DOI: 10.1038/s41467-024-50374-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2024] [Accepted: 07/09/2024] [Indexed: 07/20/2024] Open
Abstract
The complex and diverse molecular architectures along with broad biological activities of ent-kauranoids natural products make them an excellent testing ground for the invention of synthetic methods and strategies. Recent efforts notwithstanding, synthetic access to the highly oxidized enmein-type ent-kauranoids still presents considerable challenges to synthetic chemists. Here, we report the enantioselective total syntheses of C-19 oxygenated enmein-type ent-kauranoids, including (-)-macrocalyxoformins A and B and (-)-ludongnin C, along with discussion and study of synthetic strategies. The enabling feature in our synthesis is a devised Ni-catalyzed decarboxylative cyclization/radical-polar crossover/C-acylation cascade that forges a THF ring concomitantly with the β-keto ester group. Mechanistic studies reveal that the C-acylation process in this cascade reaction is achieved through a carboxylation followed by an in situ esterification. Biological evaluation of these synthetic natural products reveals the indispensable role of the ketone on the D ring in their anti-tumor efficacy.
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Affiliation(s)
- Zichen Cao
- School of Life Sciences, Peking University, 100871, Beijing, China
- National Institute of Biological Sciences, 102206, Beijing, China
| | - Wenxuan Sun
- National Institute of Biological Sciences, 102206, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China
| | - Jingfu Zhang
- National Institute of Biological Sciences, 102206, Beijing, China
| | - Junming Zhuo
- National Institute of Biological Sciences, 102206, Beijing, China
| | - Shaoqiang Yang
- National Institute of Biological Sciences, 102206, Beijing, China
| | - Xiaocui Song
- National Institute of Biological Sciences, 102206, Beijing, China
| | - Yan Ma
- National Institute of Biological Sciences, 102206, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China
| | - Panrui Lu
- National Institute of Biological Sciences, 102206, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China
| | - Ting Han
- National Institute of Biological Sciences, 102206, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China
| | - Chao Li
- National Institute of Biological Sciences, 102206, Beijing, China.
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, 100084, Beijing, China.
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3
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Zhao JX, Ge ZP, Yue JM. Cephalotane diterpenoids: structural diversity, biological activity, biosynthetic proposal, and chemical synthesis. Nat Prod Rep 2024; 41:1152-1179. [PMID: 38482919 DOI: 10.1039/d3np00067b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
Covering: up to the end of 2023Cephalotane diterpenoids are a unique class of natural products exclusive to the genus Cephalotaxus, featuring a rigid 7,6,5,6-fused tetracyclic architecture. The study of cephalotanes dates back to the 1970s, when harringtonolide (1), a Cephalotaxus troponoid with a peculiar norditerpenoid carbon skeleton, was first discovered. In recent years, prototype C20 diterpenoids proposed as cephalotane were disclosed, which triggered intense studies on this diterpenoid family. To date, a cumulative total of 105 cephalotane diterpenoids with great structural diversity and biological importance have been isolated. In addition, significant advances have been made in the field of total synthesis and biosynthesis of cephalotanes in recent years. This review provides a complete overview of the chemical structures, bioactivities, biosynthetic aspects, and completed total synthesis of all the isolated cephalotane diterpenoids, which will help guide future research on this class of compounds.
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Affiliation(s)
- Jin-Xin Zhao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, 198 East Binhai Road, Yantai, Shandong 264117, China
| | - Zhan-Peng Ge
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.
| | - Jian-Min Yue
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China.
- Shandong Laboratory of Yantai Drug Discovery, Bohai Rim Advanced Research Institute for Drug Discovery, 198 East Binhai Road, Yantai, Shandong 264117, China
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4
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Wei R, Wang Y, Zhang J, Wu C, Zhang Z, Zhang D. Visible-Light-Mediated Ring-Opening Geminal Dibromination of Alkenes via Alkoxy Radicals Enabled by Electron Donor-Acceptor Complex. Molecules 2024; 29:3281. [PMID: 39064859 PMCID: PMC11278856 DOI: 10.3390/molecules29143281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Revised: 07/08/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024] Open
Abstract
An electron donor-acceptor complex was utilized to generate alkoxy radicals from alcohols under mild conditions using visible light. This approach was combined with a hydroxybromination process to achieve the deconstructive functionalization of alkenes, leading to the production of geminal dibromides. Mechanistic investigations indicated the intermediacy of hypervalent iodine (III) compounds.
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Affiliation(s)
- Rong Wei
- State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials, Tubular Goods Research Institute of CNPC, Xi’an 710077, China; (R.W.); (Z.Z.)
| | - Yuan Wang
- State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials, Tubular Goods Research Institute of CNPC, Xi’an 710077, China; (R.W.); (Z.Z.)
| | - Juantao Zhang
- State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials, Tubular Goods Research Institute of CNPC, Xi’an 710077, China; (R.W.); (Z.Z.)
| | - Chunsheng Wu
- National Engineering Laboratory of Low Permeability Oil-Gas Field Exploration and Development, Changqing Oilfield, Xi’an 710018, China;
| | - Zhenhua Zhang
- State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials, Tubular Goods Research Institute of CNPC, Xi’an 710077, China; (R.W.); (Z.Z.)
| | - Duo Zhang
- Medicine Center, Guangxi University of Science and Technology, Liuzhou 545006, China;
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5
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Morris AO, Barriault L. Redox-Neutral Multicatalytic Cerium Photoredox-Enabled Cleavage of O-H Bearing Substrates. Chemistry 2024; 30:e202400642. [PMID: 38436591 DOI: 10.1002/chem.202400642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 03/01/2024] [Accepted: 03/04/2024] [Indexed: 03/05/2024]
Abstract
The need for synthetic methodologies capable of rapidly altering molecular structure are in high demand. Most existing methods to modify scaffolds rely on net exothermicity to drive the desired transformation. We sought to develop a general strategy for the cleavage of C-C bonds β to hydroxyl groups independent of inherent substrate strain. To this end we have applied a multicatalytic cerium photoredox-based system capable of activating O-H bonds in lactols to deliver formate esters. The same system is also capable of effecting hydrodecarboxylation and hydrodecarbonylation reactions. Initial mechanistic probes demonstrate atomic chlorine (Cl⋅) is generated under the reaction conditions, but substrate activation through cerium-alkoxides or -carboxylates cannot be ruled out.
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Affiliation(s)
- Avery O Morris
- Center for Catalysis Research and Innovation, Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie-Curie, Ottawa, Canada, K1 N 6 N5
| | - Louis Barriault
- Center for Catalysis Research and Innovation, Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie-Curie, Ottawa, Canada, K1 N 6 N5
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6
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Li C, Lu F, Cai Y, Zhang C, Shao Y, Zhang Y, Liu XY, Qin Y. Catalytic Asymmetric Total Synthesis of (-)-Garryine via an Enantioselective Heck Reaction. J Am Chem Soc 2024; 146:1081-1088. [PMID: 38113465 DOI: 10.1021/jacs.3c12171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
The first asymmetric total synthesis of the hexacyclic veatchine-type C20-diterpenoid alkaloid (-)-garryine is presented. Key steps include a Pd-catalyzed enantioselective Heck reaction, a radical cyclization, and a photoinduced C-H activation/oxazolidine formation sequence. Of note, a highly enantioselective Heck reaction developed in this work provides efficient access to 6/6/6 tricyclic compounds, in particular, containing a C19-functionalitiy, which is useful for diverse transformations.
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Affiliation(s)
- Chuang Li
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Fei Lu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yukun Cai
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Cheng Zhang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yu Shao
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yuanyuan Zhang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Xiao-Yu Liu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Yong Qin
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
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7
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Bakanas I, Lusi RF, Wiesler S, Hayward Cooke J, Sarpong R. Strategic application of C-H oxidation in natural product total synthesis. Nat Rev Chem 2023; 7:783-799. [PMID: 37730908 DOI: 10.1038/s41570-023-00534-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/08/2023] [Indexed: 09/22/2023]
Abstract
The oxidation of unactivated C-H bonds has emerged as an effective tactic in natural product synthesis and has altered how chemists approach the synthesis of complex molecules. The use of C-H oxidation methods has simplified the process of synthesis planning by expanding the choice of starting materials, limiting functional group interconversion and protecting group manipulations, and enabling late-stage diversification. In this Review, we propose classifications for C-H oxidations on the basis of their strategic purpose: type 1, which installs functionality that is used to establish the carbon skeleton of the target; type 2, which is used to construct a heterocyclic ring; and type 3, which installs peripheral functional groups. The reactions are further divided based on whether they are directed or undirected. For each classification, examples from recent literature are analysed. Finally, we provide two case studies of syntheses from our laboratory that were streamlined by the judicious use of C-H oxidation reactions.
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Affiliation(s)
- Ian Bakanas
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA
| | - Robert F Lusi
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA
| | - Stefan Wiesler
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA
| | - Jack Hayward Cooke
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA
| | - Richmond Sarpong
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA.
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8
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Fu P, Liu T, Shen Y, Lei X, Xiao T, Chen P, Qiu D, Wang Z, Zhang Y. Divergent Total Syntheses of Illicium Sesquiterpenes through Late-Stage Skeletal Reorganization. J Am Chem Soc 2023; 145:18642-18648. [PMID: 37562030 DOI: 10.1021/jacs.3c06442] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
We disclose unified, protecting-group-free, bioinspired divergent total syntheses of eight allo-cedrane and seco-prezizaane Illicium sesquiterpenes and formal syntheses of five anislactone sesquiterpenes. The efficiency of our approach derives from rapid access to the 15-carbon tricyclic carboxylic acid through cationic epoxide-ene cyclization and HAT oxygenation, transformation of this intermediate into three distinct tricyclic precursors via Lewis acid-mediated skeletal reorganizations, subsequent programmed oxidation level enhancement, and a biomimetic oxidation-initiated skeletal rearrangement cascade. Consequently, we created a synthetic correlation map of the three most prevalent Illicium sesquiterpene families.
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Affiliation(s)
- Pengfei Fu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Tao Liu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Yang Shen
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Xin Lei
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Tianjie Xiao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Peng Chen
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Dongsheng Qiu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Zhen Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Yandong Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, iCHEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
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9
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Castellino NJ, Montgomery AP, Danon JJ, Kassiou M. Late-stage Functionalization for Improving Drug-like Molecular Properties. Chem Rev 2023. [PMID: 37285604 DOI: 10.1021/acs.chemrev.2c00797] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The development of late-stage functionalization (LSF) methodologies, particularly C-H functionalization, has revolutionized the field of organic synthesis. Over the past decade, medicinal chemists have begun to implement LSF strategies into their drug discovery programs, allowing for the drug discovery process to become more efficient. Most reported applications of late-stage C-H functionalization of drugs and drug-like molecules have been to rapidly diversify screening libraries to explore structure-activity relationships. However, there has been a growing trend toward the use of LSF methodologies as an efficient tool for improving drug-like molecular properties of promising drug candidates. In this review, we have comprehensively reviewed recent progress in this emerging area. Particular emphasis is placed on case studies where multiple LSF techniques were implemented to generate a library of novel analogues with improved drug-like properties. We have critically analyzed the current scope of LSF strategies to improve drug-like properties and commented on how we believe LSF can transform drug discovery in the future. Overall, we aim to provide a comprehensive survey of LSF techniques as tools for efficiently improving drug-like molecular properties, anticipating its continued uptake in drug discovery programs.
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Affiliation(s)
| | | | - Jonathan J Danon
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Michael Kassiou
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
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10
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Levitre G, Granados A, Molander GA. Sustainable Photoinduced Decarboxylative Chlorination Mediated by Halogen Atom Transfer. GREEN CHEMISTRY : AN INTERNATIONAL JOURNAL AND GREEN CHEMISTRY RESOURCE : GC 2023; 25:560-565. [PMID: 37588672 PMCID: PMC10427136 DOI: 10.1039/d2gc04578h] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
Chlorinated organic backbones constitute important components in existing biologically active chemicals, and they are extraordinary useful intermediates in organic synthesis. Herein, an operationally simple and sustainable halodecarboxylation protocol via halogen-atom transfer (XAT) as a key step is presented. The method merges a metal-free photoredox system with (diacetoxyiodo)benzene (PIDA) as a hypervalent iodine reagent using 1,2-dihaloethanes as halogen sources to afford haloalkanes in an efficient manner. The sustainability of this protocol is highlighted by an important waste recovery protocol as well as by atom economy and carbon efficiency parameters.
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Affiliation(s)
- Guillaume Levitre
- Department of Chemistry, University of Pennsylvania, Roy and Diana Vagelos Laboratories 231 S. 34th Street, Philadelphia, PA 19104-6323 (USA)
| | - Albert Granados
- Department of Chemistry, University of Pennsylvania, Roy and Diana Vagelos Laboratories 231 S. 34th Street, Philadelphia, PA 19104-6323 (USA)
| | - Gary A Molander
- Department of Chemistry, University of Pennsylvania, Roy and Diana Vagelos Laboratories 231 S. 34th Street, Philadelphia, PA 19104-6323 (USA)
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11
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Sennari G, Gardner KE, Wiesler S, Haider M, Eggert A, Sarpong R. Unified Total Syntheses of Benzenoid Cephalotane-Type Norditerpenoids: Cephanolides and Ceforalides. J Am Chem Soc 2022; 144:19173-19185. [PMID: 36198090 DOI: 10.1021/jacs.2c08803] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Detailed herein are our synthetic studies toward the preparation of the C18- and C19-benzenoid cephalotane-type norditerpenoids. Guided by chemical network analysis, the core structure of this natural product family was constructed in a concise manner using an iterative cross-coupling, followed by a formal inverse-electron-demand [4 + 2] cycloaddition. Initial efforts to functionalize an alkene group in the [4 + 2] cycloadduct using a Mukaiyama hydration and a subsequent olefination led to the complete C18-carbon framework. While effective, this approach proved lengthy and prompted the development of a direct alkene difunctionalization that relies on borocupration to advance the cycloadduct to the natural products. Late-stage peripheral C-H functionalization facilitated access to all of the known cephanolides in 6-10 steps as well as five recently isolated ceforalides in 8-13 steps.
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Affiliation(s)
- Goh Sennari
- Department of Chemistry, University of California─Berkeley, Berkeley, California 94720, United States
| | - Kristen E Gardner
- Department of Chemistry, University of California─Berkeley, Berkeley, California 94720, United States
| | - Stefan Wiesler
- Department of Chemistry, University of California─Berkeley, Berkeley, California 94720, United States
| | - Maximilian Haider
- Department of Chemistry, University of California─Berkeley, Berkeley, California 94720, United States
| | - Alina Eggert
- Department of Chemistry, University of California─Berkeley, Berkeley, California 94720, United States
| | - Richmond Sarpong
- Department of Chemistry, University of California─Berkeley, Berkeley, California 94720, United States
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12
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Cui H, Shen Y, Wang R, Wei H, Lei X, Chen Y, Fu P, Wang H, Bi R, Zhang Y. Synthesis of Clionastatins A and B through Enhancement of Chlorination and Oxidation Levels of Testosterone. CHINESE J CHEM 2022. [DOI: 10.1002/cjoc.202200425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Hao Cui
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Yang Shen
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Ruifeng Wang
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Haoxiang Wei
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Xin Lei
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Yanyu Chen
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Pengfei Fu
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Haoxiang Wang
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Ruihao Bi
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
| | - Yandong Zhang
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China
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13
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Garagan IA, Moskalik MY, Astakhova VV, Sterkhova IV, Vashchenko AV, Albanov AI, Shainyan BA. Regioselective Oxidative Halotriflamidation of Dienes and Trienes as a Route to New Amidines and Heterocycles. ChemistrySelect 2022. [DOI: 10.1002/slct.202202231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ivan A. Garagan
- A. E. Favorsky Irkutsk Institute of Chemistry Siberian Branch of the Russian Academy of Sciences 1 Favorsky Street 664033 Irkutsk Russian Federation
| | - Mikhail Yu. Moskalik
- A. E. Favorsky Irkutsk Institute of Chemistry Siberian Branch of the Russian Academy of Sciences 1 Favorsky Street 664033 Irkutsk Russian Federation
| | - Vera V. Astakhova
- A. E. Favorsky Irkutsk Institute of Chemistry Siberian Branch of the Russian Academy of Sciences 1 Favorsky Street 664033 Irkutsk Russian Federation
| | - Irina V. Sterkhova
- A. E. Favorsky Irkutsk Institute of Chemistry Siberian Branch of the Russian Academy of Sciences 1 Favorsky Street 664033 Irkutsk Russian Federation
| | - Alexander V. Vashchenko
- A. E. Favorsky Irkutsk Institute of Chemistry Siberian Branch of the Russian Academy of Sciences 1 Favorsky Street 664033 Irkutsk Russian Federation
| | - Alexander I. Albanov
- A. E. Favorsky Irkutsk Institute of Chemistry Siberian Branch of the Russian Academy of Sciences 1 Favorsky Street 664033 Irkutsk Russian Federation
| | - Bagrat A. Shainyan
- A. E. Favorsky Irkutsk Institute of Chemistry Siberian Branch of the Russian Academy of Sciences 1 Favorsky Street 664033 Irkutsk Russian Federation
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14
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Qing Z, Mao P, Wang T, Zhai H. Asymmetric Total Syntheses of Cephalotane-Type Diterpenoids Cephanolides A-D. J Am Chem Soc 2022; 144:10640-10646. [PMID: 35653731 DOI: 10.1021/jacs.2c03978] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cephanolides A-D are cephalotane-type diterpenoids featuring a novel 6/6/6/5 tetracyclic core embedded with a bridged δ-lactone. The asymmetric and divergent total syntheses of cephanolides A-D have been accomplished, proceeding in 11-14 steps from a known alcohol. The salient features of the present work include (i) a substrate-controlled diastereoselective intermolecular Diels-Alder reaction to form the 6-6 cis-fused rings, (ii) a palladium-catalyzed formal bimolecular [2 + 2 + 2] cycloaddition reaction via a partially intermolecular cascade reaction sequence involving multiple carbometalations to rapidly install the key tetracyclic skeleton, and (iii) lactonization and late-stage oxidative diversification to complete total syntheses of the four benzenoid cephanolides.
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Affiliation(s)
- Zhineng Qing
- The State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Nano-Micro Materials Research, School of Chemical Biology and Biotechnology, Shenzhen Graduate School of Peking University, Shenzhen 518055, China
| | - Peng Mao
- The State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Nano-Micro Materials Research, School of Chemical Biology and Biotechnology, Shenzhen Graduate School of Peking University, Shenzhen 518055, China
| | - Tie Wang
- The State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Nano-Micro Materials Research, School of Chemical Biology and Biotechnology, Shenzhen Graduate School of Peking University, Shenzhen 518055, China
| | - Hongbin Zhai
- The State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Nano-Micro Materials Research, School of Chemical Biology and Biotechnology, Shenzhen Graduate School of Peking University, Shenzhen 518055, China.,Shenzhen Bay Laboratory, Shenzhen 518055, China.,Institute of Marine Biomedicine, Shenzhen Polytechnic, Shenzhen 518055, China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071, China
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15
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Cui H, Shen Y, Chen Y, Wang R, Wei H, Fu P, Lei X, Wang H, Bi R, Zhang Y. Two-Stage Syntheses of Clionastatins A and B. J Am Chem Soc 2022; 144:8938-8944. [PMID: 35576325 DOI: 10.1021/jacs.2c03872] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A concise and divergent synthesis of the polychlorinated marine steroids clionastatin A and B from inexpensive testosterone has been achieved through a unique two-stage chlorination-oxidation strategy. Key features of the two-stage synthesis include (1) conformationally controlled, highly stereoselective dichlorination at C1 and C2 and C4-OH-directed C19 oxygenation followed by a challenging neopentyl chlorination to install three chlorine atoms; (2) desaturation through one-pot photochemical dibromination-reductive debromination and anti-Markovnikov olefin oxidation by photoredox-metal dual catalysis to enhance the oxidation level of the backbone; and (3) Wharton transposition to furnish the D-ring enone. This synthesis proved that the introduction of the C19 chloride in the early stage of the synthesis secured the stability of the backbone against susceptibility to aromatization during the oxidation stage.
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Affiliation(s)
- Hao Cui
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Yang Shen
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Yanyu Chen
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Ruifeng Wang
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Haoxiang Wei
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Pengfei Fu
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Xin Lei
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Haoxiang Wang
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Ruihao Bi
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Yandong Zhang
- Department of Chemistry and Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China.,Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology, Qingdao 266000, China
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16
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Nicholson JM, Millham AB, Bucknam AR, Markham LE, Sailors XI, Micalizio GC. General Enantioselective and Stereochemically Divergent Four-Stage Approach to Fused Tetracyclic Terpenoid Systems. J Org Chem 2022; 87:3352-3362. [PMID: 35175755 PMCID: PMC9438405 DOI: 10.1021/acs.joc.1c02979] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Tetracyclic terpenoid-derived natural products are a broad class of medically relevant agents that include well-known steroid hormones and related structures, as well as more synthetically challenging congeners such as limonoids, cardenolides, lanostanes, and cucurbitanes, among others. These structurally related compound classes present synthetically disparate challenges based, in part, on the position and stereochemistry of the numerous quaternary carbon centers that are common to their tetracyclic skeletons. While de novo syntheses of such targets have been a topic of great interest for over 50 years, semisynthesis is often how synthetic variants of these natural products are explored as biologically relevant materials and how such agents are further matured as therapeutics. Here, focus was directed at establishing an efficient, stereoselective, and molecularly flexible de novo synthetic approach that could offer what semisynthetic approaches do not. In short, a unified strategy to access common molecular features of these natural product families is described that proceeds in four stages: (1) conversion of epichlorohydrin to stereodefined enynes, (2) metallacycle-mediated annulative cross-coupling to generate highly substituted hydrindanes, (3) tetracycle formation by stereoselective forging of the C9-C10 bond, and (4) group-selective oxidative rearrangement that repositions a quaternary center from C9 to C10. These studies have defined the structural features required for highly stereoselective C9-C10 bond formation and document the generality of this four-stage synthetic strategy to access a range of unique stereodefined systems, many of which bear stereochemistry/substitution/functionality not readily accessible from semisynthesis.
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Affiliation(s)
- Joshua M. Nicholson
- Department of Chemistry, Dartmouth College, Burke Laboratory, Hanover, New Hampshire 03755, United States
| | - Adam B. Millham
- Department of Chemistry, Dartmouth College, Burke Laboratory, Hanover, New Hampshire 03755, United States
| | - Andrea R. Bucknam
- Department of Chemistry, Dartmouth College, Burke Laboratory, Hanover, New Hampshire 03755, United States
| | - Lauren E. Markham
- Department of Chemistry, Dartmouth College, Burke Laboratory, Hanover, New Hampshire 03755, United States
| | - Xenia Ivanna Sailors
- Department of Chemistry, Dartmouth College, Burke Laboratory, Hanover, New Hampshire 03755, United States
| | - Glenn C. Micalizio
- Department of Chemistry, Dartmouth College, Burke Laboratory, Hanover, New Hampshire 03755, United States
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17
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Total synthesis of nine longiborneol sesquiterpenoids using a functionalized camphor strategy. Nat Chem 2022; 14:450-456. [DOI: 10.1038/s41557-021-00870-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 11/24/2021] [Indexed: 01/01/2023]
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18
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Murray PD, Cox JH, Chiappini ND, Roos CB, McLoughlin EA, Hejna BG, Nguyen ST, Ripberger HH, Ganley JM, Tsui E, Shin NY, Koronkiewicz B, Qiu G, Knowles RR. Photochemical and Electrochemical Applications of Proton-Coupled Electron Transfer in Organic Synthesis. Chem Rev 2022; 122:2017-2291. [PMID: 34813277 PMCID: PMC8796287 DOI: 10.1021/acs.chemrev.1c00374] [Citation(s) in RCA: 172] [Impact Index Per Article: 86.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Indexed: 12/16/2022]
Abstract
We present here a review of the photochemical and electrochemical applications of multi-site proton-coupled electron transfer (MS-PCET) in organic synthesis. MS-PCETs are redox mechanisms in which both an electron and a proton are exchanged together, often in a concerted elementary step. As such, MS-PCET can function as a non-classical mechanism for homolytic bond activation, providing opportunities to generate synthetically useful free radical intermediates directly from a wide variety of common organic functional groups. We present an introduction to MS-PCET and a practitioner's guide to reaction design, with an emphasis on the unique energetic and selectivity features that are characteristic of this reaction class. We then present chapters on oxidative N-H, O-H, S-H, and C-H bond homolysis methods, for the generation of the corresponding neutral radical species. Then, chapters for reductive PCET activations involving carbonyl, imine, other X═Y π-systems, and heteroarenes, where neutral ketyl, α-amino, and heteroarene-derived radicals can be generated. Finally, we present chapters on the applications of MS-PCET in asymmetric catalysis and in materials and device applications. Within each chapter, we subdivide by the functional group undergoing homolysis, and thereafter by the type of transformation being promoted. Methods published prior to the end of December 2020 are presented.
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Affiliation(s)
- Philip
R. D. Murray
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - James H. Cox
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Nicholas D. Chiappini
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Casey B. Roos
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | | | - Benjamin G. Hejna
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Suong T. Nguyen
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Hunter H. Ripberger
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Jacob M. Ganley
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Elaine Tsui
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Nick Y. Shin
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Brian Koronkiewicz
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Guanqi Qiu
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
| | - Robert R. Knowles
- Department of Chemistry, Princeton
University, Princeton, New Jersey 08544, United States
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19
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Lu Y, Xu M, Zhang Z, Zhang J, Cai Q. Catalytic Asymmetric Inverse‐Electron‐Demand Diels–Alder Reactions of 2‐Pyrones with Indenes: Total Syntheses of Cephanolides A and B. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202112223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Yang Lu
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis Fudan University 220 Handan Rd. Shanghai 200433 China
| | - Meng‐Meng Xu
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis Fudan University 220 Handan Rd. Shanghai 200433 China
| | - Zhi‐Mao Zhang
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis Fudan University 220 Handan Rd. Shanghai 200433 China
| | - Junliang Zhang
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis Fudan University 220 Handan Rd. Shanghai 200433 China
| | - Quan Cai
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis Fudan University 220 Handan Rd. Shanghai 200433 China
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20
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Jones KE, Park B, Doering NA, Baik MH, Sarpong R. Rearrangements of the Chrysanthenol Core: Application to a Formal Synthesis of Xishacorene B. J Am Chem Soc 2021; 143:20482-20490. [PMID: 34812038 PMCID: PMC9177077 DOI: 10.1021/jacs.1c10804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Reported here are substrate-dictated rearrangements of chrysanthenol derivatives prepared from verbenone to access complex bicyclic frameworks. These rearrangements set the stage for a 10-step formal synthesis of the natural product xishacorene B. Key steps include an anionic allenol oxy-Cope rearrangement and a Suárez directed C-H functionalization. The success of this work was guided by extensive computational calculations which provided invaluable insight into the reactivity of the chrysanthenol-derived systems, especially in the key oxy-Cope rearrangement.
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Affiliation(s)
- Kerry E Jones
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Bohyun Park
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
| | - Nicolle A Doering
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Mu-Hyun Baik
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
| | - Richmond Sarpong
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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21
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Liao JX, Sun JS, Hu ZN, Liu H. Advances in the Semi-Synthesis of Triterpenoids. SYNTHESIS-STUTTGART 2021. [DOI: 10.1055/a-1543-9719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AbstractRecent achievements in triterpenoid semi-synthesis are discussed in this short review, which is divided into three parts according to the type of synthetic strategy being employed. These strategies include functionalization, modification of the carbon skeleton, and glycosylation. In the section on functionalization strategies, both functional group interconversions and new functional group installations on triterpenoid starting materials are described. The section on modification of the carbon skeleton is divided into three parts according to the tactic being applied, and incorporates rearrangement of the carbon skeleton, ring scission, and introduction of an additional heterocyclic ring. Meanwhile, in the section on glycosylation, notable achievements in the semi-synthesis of both natural and artificial triterpene saponins are discussed. Overall, the pivotal transformations that have brought about striking chemical structure variations of triterpenoid starting materials are highlighted herein, and it is hoped that this short review will provide inspiration to both established and new investigators engaged in this field of research. 1 Introduction2 Semi-Synthesis of Triterpenoids via Functionalization Strategies2.1 Functionalization of Rings with Functional Groups2.2 Functionalization of a Side Chain2.3 Functionalization of Rings without Existing Functional Groups 2.4 Functionalization of Angular Methyl Groups2.5 Functionalization of Angular Methyl Groups and Functional-Group-Free Rings2.6 Multisite Modifications3 Semi-Synthesis of Triterpenoids via C-Skeleton Modification Strategies3.1 Rearrangement Tactics3.2 Ring-Opening Tactics3.3 Additional Ring Introduction Tactics4 emi-Synthesis of Triterpenoids via a Glycosylation Strategy5 Conclusions and Outlook
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22
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Zhang Y, Li X, Xu T. Total synthesis of bioactive tetracyclic norditerpene dilactones. Org Biomol Chem 2021; 19:9138-9147. [PMID: 34622268 DOI: 10.1039/d1ob01535d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tetracyclic norditerpene dilactones are an important class of terpenoids that have been isolated from both terrestrial and marine sources, typically from Podocarpus plants and from filamentous fungi. This class of molecules shares a common 6/6/6/5 tetracyclic ring skeleton, which possesses a densely oxygenated carbon framework and contiguous stereocenters. What's more challenging for synthetic chemists are the consecutive sp2-hybridized carbon centers, which exacerbates the strain/rigidity of the whole molecule. In addition, many of these molecules display promising biological activities, such as antitumor, insecticidal, anti-feedant, allelopathic, and antibiotic activities. The unique structures and interesting biological profiles of norditerpene dilactones have attracted considerable attention from synthetic chemists. Herein we summarize the synthetic efforts with respect to tetranorditerpene dilactones.
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Affiliation(s)
- Yuna Zhang
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266071, China.
| | - Xinxin Li
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266071, China.
| | - Tao Xu
- Molecular Synthesis Center & Key Laboratory of Marine Drugs, Ministry of Education; School of Medicine and Pharmacy, Ocean University of China, Qingdao, 266071, China.
- Laboratory for Marine Drugs and Bioproducts and Open Studio for Druggability Research of Marine Natural Products, Pilot NLMST, Jimo Qingdao, China
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23
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Lu Y, Xu MM, Zhang ZM, Zhang J, Cai Q. Catalytic Asymmetric Inverse-Electron-Demand Diels-Alder Reactions of 2-Pyrones with Indenes: Total Syntheses of Cephanolides A and B. Angew Chem Int Ed Engl 2021; 60:26610-26615. [PMID: 34668619 DOI: 10.1002/anie.202112223] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/11/2021] [Indexed: 12/15/2022]
Abstract
An inverse-electron-demand Diels-Alder (IEDDA) reaction could complement the conventional normal-electron-demand Diels-Alder reaction in the synthesis of six-membered carbocycles. However, catalytic asymmetric all-carbon-based IEDDA reactions are underdeveloped. Herein, we disclosed a copper-catalyzed asymmetric IEDDA reaction using electron-deficient 3-carboalkoxyl-2-pyrones and electronically unbiased indenes as reactants. This method enables the rapid and enantioselective construction of a wide range of hexahydrofluorenyl bridged-lactone scaffolds. Using this method, asymmetric total syntheses of cephanolides A and B were accomplished.
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Affiliation(s)
- Yang Lu
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis, Fudan University, 220 Handan Rd., Shanghai, 200433, China
| | - Meng-Meng Xu
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis, Fudan University, 220 Handan Rd., Shanghai, 200433, China
| | - Zhi-Mao Zhang
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis, Fudan University, 220 Handan Rd., Shanghai, 200433, China
| | - Junliang Zhang
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis, Fudan University, 220 Handan Rd., Shanghai, 200433, China
| | - Quan Cai
- Department of Chemistry and Research Center for Molecular Recognition and Synthesis, Fudan University, 220 Handan Rd., Shanghai, 200433, China
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24
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Chang L, An Q, Duan L, Feng K, Zuo Z. Alkoxy Radicals See the Light: New Paradigms of Photochemical Synthesis. Chem Rev 2021; 122:2429-2486. [PMID: 34613698 DOI: 10.1021/acs.chemrev.1c00256] [Citation(s) in RCA: 139] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Alkoxy radicals are highly reactive species that have long been recognized as versatile intermediates in organic synthesis. However, their development has long been impeded due to a lack of convenient methods for their generation. Thanks to advances in photoredox catalysis, enabling facile access to alkoxy radicals from bench-stable precursors and free alcohols under mild conditions, research interest in this field has been renewed. This review comprehensively summarizes the recent progress in alkoxy radical-mediated transformations under visible light irradiation. Elementary steps for alkoxy radical generation from either radical precursors or free alcohols are central to reaction development; thus, each section is categorized and discussed accordingly. Throughout this review, we have focused on the different mechanisms of alkoxy radical generation as well as their impact on synthetic utilizations. Notably, the catalytic generation of alkoxy radicals from abundant alcohols is still in the early stage, providing intriguing opportunities to exploit alkoxy radicals for diverse synthetic paradigms.
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Affiliation(s)
- Liang Chang
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 200032 Shanghai, China.,School of Pharmacy, Nanjing University of Chinese Medicine, 210023 Nanjing, China
| | - Qing An
- School of Physical Science and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Lingfei Duan
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 200032 Shanghai, China
| | - Kaixuan Feng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 200032 Shanghai, China
| | - Zhiwei Zuo
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 200032 Shanghai, China
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25
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Zhang W, Li L, Li CC. Synthesis of natural products containing highly strained trans-fused bicyclo[3.3.0]octane: historical overview and future prospects. Chem Soc Rev 2021; 50:9430-9442. [PMID: 34286715 DOI: 10.1039/d0cs01471k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Owing to high strain energy, molecules with trans-fused bicyclo[3.3.0]octane ring systems are very difficult to synthesize, and there are very few approaches to access them. Recently, a number of natural products with such ring systems have been made by the synthetic community. However, there has been no review in this field before. This review provides a systematic and comprehensive discussion on the synthesis of natural products containing trans-fused bicyclo[3.3.0]octanes and the historical context of this work. The prospects for future research in this field are also discussed. Covering the literature before 2021, this review aims to offer a helpful reference for total synthesis of highly strained natural products containing trans-fused bicyclo[3.3.0]octane ring systems.
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Affiliation(s)
- Wen Zhang
- Shenzhen Grubbs Institute and Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China.
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26
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Koch V, Bräse S. An Intramolecular Iodine‐Catalyzed C(sp
3
)−H Oxidation as a Versatile Tool for the Synthesis of Tetrahydrofurans. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Vanessa Koch
- Institute of Organic Chemistry (IOC) Karlsruhe Institute for Technology (KIT) Fritz-Haber-Weg 6, Campus South 76131 Karlsruhe Germany
| | - Stefan Bräse
- Institute of Organic Chemistry (IOC) Karlsruhe Institute for Technology (KIT) Fritz-Haber-Weg 6, Campus South 76131 Karlsruhe Germany
- Institute of Biological and Chemical Systems – Functional Molecular Systems (IBCS-FMS) Hermann-von-Helmholtz Platz 1, Campus North 76344 Eggenstein-Leopoldshafen Germany
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27
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Wang Z, Hui C. Contemporary advancements in the semi-synthesis of bioactive terpenoids and steroids. Org Biomol Chem 2021; 19:3791-3812. [PMID: 33949606 DOI: 10.1039/d1ob00448d] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Many natural products have intriguing biological properties that arise from their fascinating chemical structures. However, the intrinsic complexity of the structural skeleton and the reactive functional groups on natural products pose tremendous challenges to chemical syntheses. Semi-synthesis uses chemical compounds isolated from natural sources as the starting materials to produce other novel compounds with distinct chemical and medicinal properties. In particular, advancements in various types of sp3 C-H bond functionalization reactions and skeletal rearrangement methods have contributed to the re-emergence of semi-synthesis as an efficient approach for the synthesis of structurally complex bioactive natural products. Here, we begin with a brief discussion of several bioactive natural products that were obtained via a semi-synthetic approach between 2008 and 2015 and we then discuss in-depth contemporary advancements in the semi-synthesis of bioactive terpenoids and steroids reported during 2016-2020.
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Affiliation(s)
- Zhuo Wang
- Southern University of Science and Technology, School of Medicine, Shenzhen, 518055, People's Republic of China.
| | - Chunngai Hui
- Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China
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28
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Aizawa SI, Takeuchi Y. Kinetic Investigation of Pd(II)-Catalyzed Ortho C-H Iodination of Benzamide with I 2. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20210002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Sen-ichi Aizawa
- Faculty of Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555, Japan
| | - Yoichi Takeuchi
- Faculty of Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555, Japan
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29
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Yang Z, Niu Y, He X, Chen S, Liu S, Li Z, Chen X, Zhang Y, Lan Y, Shen X. Tuning the reactivity of alkoxyl radicals from 1,5-hydrogen atom transfer to 1,2-silyl transfer. Nat Commun 2021; 12:2131. [PMID: 33837201 PMCID: PMC8035221 DOI: 10.1038/s41467-021-22382-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 03/04/2021] [Indexed: 01/10/2023] Open
Abstract
Controlling the reactivity of reactive intermediates is essential to achieve selective transformations. Due to the facile 1,5-hydrogen atom transfer (HAT), alkoxyl radicals have been proven to be important synthetic intermediates for the δ-functionalization of alcohols. Herein, we disclose a strategy to inhibit 1,5-HAT by introducing a silyl group into the α-position of alkoxyl radicals. The efficient radical 1,2-silyl transfer (SiT) allows us to make various α-functionalized products from alcohol substrates. Compared with the direct generation of α-carbon radicals from oxidation of α-C-H bond of alcohols, the 1,2-SiT strategy distinguishes itself by the generation of alkoxyl radicals, the tolerance of many functional groups, such as intramolecular hydroxyl groups and C-H bonds next to oxygen atoms, and the use of silyl alcohols as limiting reagents.
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Affiliation(s)
- Zhaoliang Yang
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Yunhong Niu
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Xiaoqian He
- School of Chemistry and Chemical Engineering, Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing, People's Republic of China
| | - Suo Chen
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Shanshan Liu
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Zhengyu Li
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Xiang Chen
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Yunxiao Zhang
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China
| | - Yu Lan
- School of Chemistry and Chemical Engineering, Chongqing Key Laboratory of Theoretical and Computational Chemistry, Chongqing University, Chongqing, People's Republic of China.
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, People's Republic of China.
| | - Xiao Shen
- The Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds and Materials, Ministry of Education, Wuhan University, Wuhan, People's Republic of China.
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30
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Kim K, Kim N, Hong S. Visible
Light‐Induced
Intramolecular C─O Bond Formation via 1,
5‐Hydrogen
Atom Transfer Strategy. B KOREAN CHEM SOC 2021. [DOI: 10.1002/bkcs.12234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kiho Kim
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS) Daejeon, 34141 Korea
- Department of Chemistry Korea Advanced Institute of Science and Technology Daejeon, 34141 Korea
| | - Namhoon Kim
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS) Daejeon, 34141 Korea
- Department of Chemistry Korea Advanced Institute of Science and Technology Daejeon, 34141 Korea
| | - Sungwoo Hong
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS) Daejeon, 34141 Korea
- Department of Chemistry Korea Advanced Institute of Science and Technology Daejeon, 34141 Korea
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31
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Varenikov A, Shapiro E, Gandelman M. Decarboxylative Halogenation of Organic Compounds. Chem Rev 2021; 121:412-484. [PMID: 33200917 PMCID: PMC7884003 DOI: 10.1021/acs.chemrev.0c00813] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Indexed: 12/13/2022]
Abstract
Decarboxylative halogenation, or halodecarboxylation, represents one of the fundamental key methods for the synthesis of ubiquitous organic halides. The method is based on conversion of carboxylic acids to the corresponding organic halides via selective cleavage of a carbon-carbon bond between the skeleton of the molecule and the carboxylic group and the liberation of carbon dioxide. In this review, we discuss and analyze major approaches for the conversion of alkanoic, alkenoic, acetylenic, and (hetero)aromatic acids to the corresponding alkyl, alkenyl, alkynyl, and (hetero)aryl halides. These methods include the preparation of families of valuable organic iodides, bromides, chlorides, and fluorides. The historic and modern methods for halodecarboxylation reactions are broadly discussed, including analysis of their advantages and drawbacks. We critically address the features, reaction selectivity, substrate scopes, and limitations of the approaches. In the available cases, mechanistic details of the reactions are presented, and the generality and uniqueness of the different mechanistic pathways are highlighted. The challenges, opportunities, and future directions in the field of decarboxylative halogenation are provided.
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Affiliation(s)
- Andrii Varenikov
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 3200008, Israel
| | - Evgeny Shapiro
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 3200008, Israel
| | - Mark Gandelman
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 3200008, Israel
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32
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Abstract
The focus article discusses the innovation of hypervalent(iii) iodine regarding skeletal rearrangement, cycloaddition and cyclization, and sp3 C–H functionalization in natural product synthesis.
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Affiliation(s)
- Zhuo Wang
- Southern University of Science and Technology
- School of Medicine
- Shenzhen
- People's Republic of China
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33
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Tsui E, Wang H, Knowles RR. Catalytic generation of alkoxy radicals from unfunctionalized alcohols. Chem Sci 2020; 11:11124-11141. [PMID: 33384861 PMCID: PMC7747465 DOI: 10.1039/d0sc04542j] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 09/21/2020] [Indexed: 12/12/2022] Open
Abstract
Alkoxy radicals have long been recognized as powerful synthetic intermediates with well-established reactivity patterns. Due to the high bond dissociation free energy of aliphatic alcohol O-H bonds, these radicals are difficult to access through direct homolysis, and conventional methods have instead relied on activation of O-functionalized precursors. Over the past decade, however, numerous catalytic methods for the direct generation of alkoxy radicals from simple alcohol starting materials have emerged and created opportunities for the development of new transformations. This minireview discusses recent advances in catalytic alkoxy radical generation, with particular emphasis on progress toward the direct activation of unfunctionalized alcohols enabled by transition metal and photoredox catalysis.
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Affiliation(s)
- Elaine Tsui
- Department of Chemistry , Princeton University , Princeton , NJ 08544 , USA .
| | - Huaiju Wang
- Department of Chemistry , Princeton University , Princeton , NJ 08544 , USA .
| | - Robert R Knowles
- Department of Chemistry , Princeton University , Princeton , NJ 08544 , USA .
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34
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Mu T, Wei B, Zhu D, Yu B. Site-selective C-H hydroxylation of pentacyclic triterpenoids directed by transient chiral pyridine-imino groups. Nat Commun 2020; 11:4371. [PMID: 32873790 PMCID: PMC7462855 DOI: 10.1038/s41467-020-18138-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 08/05/2020] [Indexed: 01/18/2023] Open
Abstract
Pentacyclic triterpenoids (PTs) constitute one of the biggest families of natural products, many with higher oxidation state at the D/E rings possess a wide spectrum of biological activties but are poorly accessible. Here we report a site-selective C-H hydroxylation at the D/E rings of PTs paving a way toward these important natural products. We find that Schönecker and Baran's Cu-mediated aerobic oxidation can be applied and become site-selective on PT skeletons, as being effected unexpectedly by the chirality of the transient pyridine-imino directing groups. To prove the applicability, starting from the most abundant triterpenoid feedstock oleanane, three representative saponins bearing hydroxyl groups at C16 or C22 are expeditiously synthesized, and barringtogenol C which bears hydroxyl groups at C16, C21, and C22 is synthesized via a sequential hydroxylation as the key steps.
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Affiliation(s)
- Tong Mu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Bingcheng Wei
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Dapeng Zhu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Biao Yu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, 1 Sub-lane Xiangshan, Hangzhou, 310024, China.
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35
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Berger M, Knittl-Frank C, Bauer S, Winter G, Maulide N. Application of Relay C−H Oxidation Logic to Polyhydroxylated Oleanane Triterpenoids. Chem 2020. [DOI: 10.1016/j.chempr.2020.04.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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36
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Harmange Magnani CS, Thach DQ, Haelsig KT, Maimone TJ. Syntheses of Complex Terpenes from Simple Polyprenyl Precursors. Acc Chem Res 2020; 53:949-961. [PMID: 32202757 DOI: 10.1021/acs.accounts.0c00055] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
From structure elucidation and biogenesis to synthetic methodology and total synthesis, terpene natural products have profoundly influenced the development of organic chemistry. Moreover, their myriad functional attributes range from fragrance to pharmaceuticals and have had great societal impact. Ruzicka's formulation of the "biogenetic isoprene rule," a Nobel Prize winning discovery now over 80 years old, allowed for identification of higher order terpene (aka "isoprenoid") structures from simple five-carbon isoprene fragments. Notably, the isoprene rule still holds pedagogical value to students of organic chemistry today. Our laboratory has completed syntheses of over two dozen terpene and meroterpene structures to date, and the isoprene rule has served as a key pattern recognition tool for our synthetic planning purposes. At the strategic level, great opportunity exists in finding unique and synthetically simplifying ways to connect the formal C5 isoprene fragments embedded in terpenes. Biomimetic cationic polyene cyclizations represent the earliest incarnation of this idea, which has facilitated expedient routes to certain terpene polycycle classes. Nonetheless, a large swath of terpene chemical space remains inaccessible using this approach.In this Account, we describe strategic insight into our endeavors in terpene synthesis published over the last five years. We show how biosynthetic understanding, combined with a desire to utilize abundant and inexpensive [C5]n building blocks, has led to efficient, abiotic syntheses of multiple complex terpenes with disparate ring systems. Informed by nature, but unconstrained by its processes, our synthetic assembly exploits chemical reactivity across diverse reaction types-including radical, anionic, pericyclic, and metal-mediated transformations.First, we detail an eight-step synthesis of the cembrane diterpene chatancin from dihydrofarnesal using a bioinspired-but not -mimetic-cycloaddition. Next, we describe the assembly of the antimalarial cardamom peroxide using a polyoxygenation cascade to fuse multiple units of molecular oxygen onto a dimeric skeleton. This three-to-four-step synthesis arises from (-)-myrtenal, an inexpensive pinene oxidation product. We then show how a radical cyclization cascade can forge the hallmark cyclooctane ring system of the complex sesterterpene 6-epi-ophiobolin N from two simple polyprenyl precursors, (-)-linalool and farnesol. To access the related, more complex metabolite 6-epi-ophiobolin A, we exploited the plasticity of our synthetic route and found that use of geraniol (C10) rather than farnesol (C15) gave us the flexibility needed to address the additional oxidation found in this congener. Following this work, we describe two strategies to access several guaianolide sesquiterpenes. Retrosynthetic disconnection to monoterpenes, carvone or (-)-linalool, coupled with a powerful allylation strategy allowed us to address guaianolides with disparate stereochemical motifs. Finally, we examine a semisynthetic approach to the illicium sesquiterpenes from the abundant 15-carbon feedstock terpene (+)-cedrol using an abiotic ring shift and multiple C-H oxidation reactions inspired by a postulated biosynthesis of this natural product class.
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Affiliation(s)
| | - Danny Q. Thach
- Department of Chemistry, University of California—Berkeley, Berkeley, California 94720, United States
| | - Karl T. Haelsig
- Department of Chemistry, University of California—Berkeley, Berkeley, California 94720, United States
| | - Thomas J. Maimone
- Department of Chemistry, University of California—Berkeley, Berkeley, California 94720, United States
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37
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Taspinar Ö, Wilczek T, Erver J, Breugst M, Neudörfl JM, Schmalz HG. Synthesis of the 8,19-Epoxysteroid Eurysterol A. Chemistry 2020; 26:4256-4260. [PMID: 32031278 PMCID: PMC7187428 DOI: 10.1002/chem.202000585] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Indexed: 01/21/2023]
Abstract
We report the first chemical synthesis of eurysterol A, a cytotoxic and antifungal marine steroidal sulfate with a unique C8−C19 oxy‐bridged cholestane skeleton. After C19 hydroxylation of cholesteryl acetate, used as an inexpensive commercial starting material, the challenging oxidative functionalization of ring B was achieved by two different routes to set up a 5α‐hydroxy‐7‐en‐6‐one moiety. As a key step, an intramolecular oxa‐Michael addition was exploited to close the oxy‐bridge (8β,19‐epoxy unit). DFT calculations show this reversible transformation being exergonic by about −30 kJ mol−1. Along the optimized (scalable) synthetic sequence, the target natural product was obtained in only 11 steps in 5 % overall yield. In addition, an access to (isomeric) 7β,19‐epoxy steroids with a previously unknown pentacyclic ring system was discovered.
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Affiliation(s)
- Ömer Taspinar
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Köln, Germany
| | - Tobias Wilczek
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Köln, Germany
| | - Julian Erver
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Köln, Germany
| | - Martin Breugst
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Köln, Germany
| | - Jörg-Martin Neudörfl
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Köln, Germany
| | - Hans-Günther Schmalz
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Köln, Germany
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38
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Abstract
Alkoxy radicals have long been known to enable remote C-H functionalization via 1,5-hydrogen atom abstraction. However, methods for their generation traditionally have relied upon highly oxidizing metals, ultraviolet radiation, or preformed peroxide intermediates, which has prevented the development of many desirable transformations. Herein we report a new bench-stable precursor that decomposes to free alkoxy radicals via a previously unreported single-electron oxidation pathway. This new precursor enables the fluorination and chlorination of remote C-H bonds under exceptionally mild conditions with exceedingly high monoselectivity. Iterative use of this precursor enables the introduction of a second halogen atom, granting access to remote dihalide motifs, including CF2 and CFCl.
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Affiliation(s)
- Alastair N Herron
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Dongxin Liu
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Guoqin Xia
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Jin-Quan Yu
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
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39
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Li Q, Yang H, Tang Y. Recent advances in the synthesis of plakortin-type polyketides. Org Biomol Chem 2020; 18:9371-9384. [PMID: 33185636 DOI: 10.1039/d0ob01930e] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Plakortin-type polyketides represent a growing family of sponge-derived marine natural products that display notable structural and biological diversity. In particular, a series of polycyclic plakortin polyketides, namely hippolachnin A and gracilioethers, have been identified in recent years, which attract immense interest from the synthetic community owing to their unique molecular architectures and promising biomedical potential. A number of elegant total syntheses of these targets and some synthetic studies have been performed through either bio-inspired or rationally designed strategies. This focused review aims to provide an up-to-date summary of the progress in the chemical synthesis of plakortin polyketides, with an emphasis on the key synthetic elements enabling the rapid assembly of their core skeletons.
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Affiliation(s)
- Qingong Li
- School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing 100084, China. and Shandong NHU Pharmaceutical Co., Ltd., No. 01999 Xiangjiang West Second Street, Binhai Economic and Technological Development Zone, Weifang, Shandong Province, China
| | - Hongzhi Yang
- School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing 100084, China.
| | - Yefeng Tang
- School of Pharmaceutical Sciences, MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing 100084, China.
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40
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Shi JL, Wang Y, Wang Z, Dou B, Wang J. Ring-opening iodination and bromination of unstrained cycloalkanols through β-scission of alkoxy radicals. Chem Commun (Camb) 2020; 56:5002-5005. [DOI: 10.1039/d0cc01720e] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ring-opening iodination or bromination of unstrained cycloalkanols with NaI or NaBr and PhI(OAc)2 under visible light irradiation is developed.
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Affiliation(s)
- Jiang-Ling Shi
- Beijing National Laboratory of Molecular Sciences (BNLMS)
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education
- College of Chemistry
- Peking University
- Beijing 100871
| | - Yuankai Wang
- Beijing National Laboratory of Molecular Sciences (BNLMS)
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education
- College of Chemistry
- Peking University
- Beijing 100871
| | - Zixuan Wang
- Beijing National Laboratory of Molecular Sciences (BNLMS)
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education
- College of Chemistry
- Peking University
- Beijing 100871
| | - Bowen Dou
- Beijing National Laboratory of Molecular Sciences (BNLMS)
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education
- College of Chemistry
- Peking University
- Beijing 100871
| | - Jianbo Wang
- Beijing National Laboratory of Molecular Sciences (BNLMS)
- Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education
- College of Chemistry
- Peking University
- Beijing 100871
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41
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Koch V, Nieger M, Bräse S. Towards the synthesis of calotropin and related cardenolides from 3-epiandrosterone: A-ring related modifications. Org Chem Front 2020. [DOI: 10.1039/d0qo00269k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Calotropin and related cardiac glycosides isolated from plants such as calotropis gigantea represent an interesting target for biological investigations and are based on a cardiac steroid that is doubly connected to a sugar moiety.
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Affiliation(s)
- Vanessa Koch
- Institute of Organic Chemistry
- Karlsruhe Institute of Technology (KIT)
- 76131 Karlsruhe
- Germany
| | - Martin Nieger
- Department of Chemistry
- University of Helsinki
- 00014 Helsinki
- Finland
| | - Stefan Bräse
- Institute of Organic Chemistry
- Karlsruhe Institute of Technology (KIT)
- 76131 Karlsruhe
- Germany
- Institute for Biological and Chemical Systems – Functional Molecular Systems (IBCS-FMS)
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42
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Duecker FL, Heinze RC, Heretsch P. Synthesis of Swinhoeisterol A, Dankasterone A and B, and Periconiastone A by Radical Framework Reconstruction. J Am Chem Soc 2019; 142:104-108. [DOI: 10.1021/jacs.9b12899] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Fenja L. Duecker
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
| | - Robert C. Heinze
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
| | - Philipp Heretsch
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
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43
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Kumar R, Sayala KD, Cao Y, Tsarevsky NV. Functionalization of cis‐1,4‐polyisoprene using hypervalent iodine compounds with tetrazole ligands. JOURNAL OF POLYMER SCIENCE 2019. [DOI: 10.1002/pola.29500] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Rajesh Kumar
- Department of Chemistry Southern Methodist University 3215 Daniel Avenue Dallas, Texas 75275
| | - Kapil Dev Sayala
- Department of Chemistry Southern Methodist University 3215 Daniel Avenue Dallas, Texas 75275
| | - Yakun Cao
- Department of Chemistry Southern Methodist University 3215 Daniel Avenue Dallas, Texas 75275
| | - Nicolay V. Tsarevsky
- Department of Chemistry Southern Methodist University 3215 Daniel Avenue Dallas, Texas 75275
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44
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A biocatalytic hydroxylation-enabled unified approach to C19-hydroxylated steroids. Nat Commun 2019; 10:3378. [PMID: 31358750 PMCID: PMC6662754 DOI: 10.1038/s41467-019-11344-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Accepted: 07/10/2019] [Indexed: 11/11/2022] Open
Abstract
Steroidal C19-hydroxylation is pivotal to the synthesis of naturally occurring bioactive C19-OH steroids and 19-norsteroidal pharmaceuticals. However, realizing this transformation is proved to be challenging through either chemical or biological synthesis. Herein, we report a highly efficient method to synthesize 19-OH-cortexolone in 80% efficiency at the multi-gram scale. The obtained C19-OH-cortexolone can be readily transformed to various synthetically useful intermediates including the industrially valuable 19-OH-androstenedione, which can serve as a basis for synthesis of C19-functionalized steroids as well as 19-nor steroidal drugs. Using this biocatalytic C19-hydroxylation method, the unified synthesis of six C19-hydroxylated pregnanes is achieved in just 4 to 9 steps. In addition, the structure of sclerosteroid B is revised on the basis of our synthesis. C19 hydroxylation is a unique feature of some bioactive steroids. Here, the authors developed a direct C19 hydroxylation approach to scalably access 19-OH-cortexolone in the host T. cucumeris and then converted the product into various pharmaceutically useful products via chemical synthesis.
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45
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Miyagawa T, Inuki S, Oishi S, Ohno H. Construction of Quaternary Carbon Stereocenter of α-Tertiary Amine through Remote C-H Functionalization of Tris Derivatives: Enantioselective Total Synthesis of Myriocin. Org Lett 2019; 21:5485-5490. [PMID: 31287325 DOI: 10.1021/acs.orglett.9b01778] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We describe the development of a strategy for the construction of the quaternary carbon stereocenter of α-tertiary amines. This strategy highlights a site-selective C-H functionalization involving an alkoxy-radical-triggered 1,5-hydrogen transfer (1,5-HAT) reaction of a conformationally fixed spiro-compound derived from trishydroxymethylaminomethane (Tris). The utilization of this strategy enabled an enantioselective total synthesis of myriocin, a naturally occurring sphingosine analog that displays potent immunosuppressive activity.
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Affiliation(s)
- Takashi Miyagawa
- Graduate School of Pharmaceutical Sciences , Kyoto University , Sakyo-ku, Kyoto 606-8501 , Japan
| | - Shinsuke Inuki
- Graduate School of Pharmaceutical Sciences , Kyoto University , Sakyo-ku, Kyoto 606-8501 , Japan
| | - Shinya Oishi
- Graduate School of Pharmaceutical Sciences , Kyoto University , Sakyo-ku, Kyoto 606-8501 , Japan
| | - Hiroaki Ohno
- Graduate School of Pharmaceutical Sciences , Kyoto University , Sakyo-ku, Kyoto 606-8501 , Japan
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46
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Craig RA, Smith RC, Roizen JL, Jones AC, Virgil SC, Stoltz BM. Unified Enantioselective, Convergent Synthetic Approach toward the Furanobutenolide-Derived Polycyclic Norcembranoid Diterpenes: Synthesis of a Series of Ineleganoloids by Oxidation-State Manipulation of the Carbocyclic Core. J Org Chem 2019; 84:7722-7746. [PMID: 31066273 DOI: 10.1021/acs.joc.9b00635] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Late-stage synthetic efforts to advance the enatio- and diastereoselectively constructed [6,7,5,5]-fused tetracyclic scaffold toward the polycyclic norditerpenoid ineleganolide are disclosed. The described investigations focus on oxidation-state manipulation around the central cycloheptane ring. Computational evaluation of ground-state energies of dihydroineleganolide is used to rationalize empirical observations and provide insight for further synthetic development, enhancing the understanding of the conformational constraints of these compact polycyclic structures. Advanced synthetic manipulations generated a series of natural product-like compounds termed the ineleganoloids.
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Affiliation(s)
- Robert A Craig
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States
| | - Russell C Smith
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States
| | - Jennifer L Roizen
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States
| | - Amanda C Jones
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States
| | - Scott C Virgil
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States
| | - Brian M Stoltz
- Warren and Katherine 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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47
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Abstract
The first enantioselective total syntheses of highly complex hexacyclic meroterpenoids STR-2 and -9 (strongylophorine (STR)) are reported. Key elements of the synthetic route include the use of Robinson-type annulation reaction to construct the tricyclic terpenoid building block and a highly efficient PIDA-mediated 1,3-diaxial sp3 C-H activation to incorporate the requisite δ-lactone moiety. This route also enables the determination of absolute configuration of the synthesized natural products.
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Affiliation(s)
- Dattatraya H Dethe
- Department of Chemistry , Indian Institute of Technology , Kanpur , Uttar Pradesh 208016 , India
| | - Susanta Kumar Sau
- Department of Chemistry , Indian Institute of Technology , Kanpur , Uttar Pradesh 208016 , India
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48
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Dochain S, Nshimyumuremyi JB, Dewez DF, Body JF, Elias B, Singleton ML, Markó IE. Electrochemical and photochemical approaches for the synthesis of the C28–C38 fragment of okadaic acid. Tetrahedron 2019. [DOI: 10.1016/j.tet.2019.02.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Yang QL, Wang XY, Wang TL, Yang X, Liu D, Tong X, Wu XY, Mei TS. Palladium-Catalyzed Electrochemical C–H Bromination Using NH4Br as the Brominating Reagent. Org Lett 2019; 21:2645-2649. [DOI: 10.1021/acs.orglett.9b00629] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Qi-Liang Yang
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China
| | - Xiang-Yang Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China
| | - Tong-Lin Wang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China
| | - Xiang Yang
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China
| | - Dong Liu
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China
| | - Xiaofeng Tong
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Xin-Yan Wu
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Tian-Sheng Mei
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China
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Li GX, Hu X, He G, Chen G. Photoredox-mediated remote C(sp 3)-H heteroarylation of free alcohols. Chem Sci 2019; 10:688-693. [PMID: 30774869 PMCID: PMC6345347 DOI: 10.1039/c8sc04134b] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 10/27/2018] [Indexed: 01/05/2023] Open
Abstract
We report an efficient and economical method for remote δ C(sp3)-H heteroarylation of free aliphatic alcohols using a hypervalent iodine PFBI-OH oxidant under photoredox catalysis. The reaction sequence involves in situ alcoholysis of PFBI-OH with alcohol, generation of an alkoxy radical intermediate by SET reduction, 1,5-HAT, and Minisci-type C-C bond formation. This method uses a slight excess of alcohols, can facilitate reaction at δ methyl and methylene positions, and has been successfully applied to modification of complex drug molecules.
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Affiliation(s)
- Guo-Xing Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry , College of Chemistry , Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Nankai University , Tianjin 300071 , China .
| | - Xiafei Hu
- State Key Laboratory and Institute of Elemento-Organic Chemistry , College of Chemistry , Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Nankai University , Tianjin 300071 , China .
| | - Gang He
- State Key Laboratory and Institute of Elemento-Organic Chemistry , College of Chemistry , Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Nankai University , Tianjin 300071 , China .
| | - Gong Chen
- State Key Laboratory and Institute of Elemento-Organic Chemistry , College of Chemistry , Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Nankai University , Tianjin 300071 , China .
- Department of Chemistry , The Pennsylvania State University , 104 Chemistry Building, University Park , PA 16802 , USA .
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