1
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Davas DS, Gopalakrishnan DK, Kumar D, Vaitla J. Ru-Catalyzed Benzannulation of Vinyl Sulfoxonium Ylide with Electron-Deficient Alkynes and Alkenes. Org Lett 2022; 24:8359-8363. [DOI: 10.1021/acs.orglett.2c03388] [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)
- Daksh Singh Davas
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
| | | | - Deepesh Kumar
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
| | - Janakiram Vaitla
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
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2
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Qin H, Xie Q, He L. Diastereoselective synthesis of chroman bearing spirobenzofuranone scaffolds via oxa-Michael/1,6-conjugated addition of para-quinone methides with benzofuranone-type olefins. RSC Adv 2022; 12:16684-16687. [PMID: 35754894 PMCID: PMC9169491 DOI: 10.1039/d2ra03031d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 05/29/2022] [Indexed: 12/17/2022] Open
Abstract
A simple and convenient cyclization of ortho-hydroxyphenyl-substituted para-quinone methides with benzofuran-2-one type active olefins via oxa-Michael/1,6-conjugated addition has been developed, which afforded an easy access to enriched functionalized chroman-spirobenzofuran-2-one scaffolds with good to excellent yields (up to 90%) and diastereoselectivities (up to >19 : 1 dr). This reaction provided an efficient method for constructing desired spirocyclic compounds combining both well-known heterocyclic pharmacophores chroman and benzofuran-2-one. Highly diastereoselective synthesis of spirocyclic compounds combining both well-known heterocyclic pharmacophores chroman and benzofuran-2-one.![]()
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Affiliation(s)
- Hongmei Qin
- College of Chemistry and Materials Engineering, Guiyang University, Guiyang, 550005, P. R. China
| | - Qimei Xie
- College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637002, P. R. China
| | - Long He
- College of Chemistry and Materials Engineering, Guiyang University, Guiyang, 550005, P. R. China
- College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637002, P. R. China
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3
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Mudulkar S, Kolla ST, Sridhar B, Bhimapaka CR. BF 3·OEt 2-catalyzed synthesis of 2,2′-spirobi-2 H-1-benzopyrans from 2 H-chromenes. Org Biomol Chem 2022; 20:8145-8148. [DOI: 10.1039/d2ob01286c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A new approach was developed for the construction of 2,2′-spirobi-2H-1-benzopyrancarboxylates by reacting ethyl 2-(chloromethyl)-2-hydroxy-2H-chromene-3-carboxylates with salicylaldehydes through the formation of C–C and C–O bonds in one pot.
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Affiliation(s)
- Sairam Mudulkar
- Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India
| | - Sai Teja Kolla
- Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India
| | - Balasubramanian Sridhar
- Department of Analytical & Structural Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India
| | - China Raju Bhimapaka
- Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad-500 007, India
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4
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Sun G, Wang Z, Deng Z, Luo Z, Zhang J. Development of novel C2-symmetrical [5]oxahelicenoid diols. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Gai S, Henneveld JS, Cording AP, Badart MP, Lucas NT, Hawkins BC. The synthesis of benzannulated spiroketals from 1,1-diacyl-2-phenylcyclopropanes. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.152984] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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6
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Sravanthi K, Khan FA. Brønsted acid-induced synthesis of methyl benzofurans via Grob type fragmentation of norbornyl derivatives. Tetrahedron Lett 2020. [DOI: 10.1016/j.tetlet.2020.152351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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7
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Dissanayake I, Hart JD, Becroft EC, Sumby CJ, Newton CG. Bisketene Equivalents as Diels–Alder Dienes. J Am Chem Soc 2020; 142:13328-13333. [DOI: 10.1021/jacs.0c06306] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Isuru Dissanayake
- Department of Chemistry, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Jacob D. Hart
- Department of Chemistry, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Emma C. Becroft
- Department of Chemistry, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Christopher J. Sumby
- Department of Chemistry, The University of Adelaide, Adelaide, SA 5005, Australia
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8
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Zhou L, Yu SY, Tang Y, Wang L. Facile Stereoselective Approach to Diverse Spiroheterocyclic Tetrahydropyrans: Concise Synthesis of (+)-Broussonetine G and H. Angew Chem Int Ed Engl 2019; 58:15016-15020. [PMID: 31390139 DOI: 10.1002/anie.201907353] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/25/2019] [Indexed: 01/02/2023]
Abstract
A highly diastereoselective copper-catalyzed multicomponent cyclization of exocyclic enol ethers/enamines with methylene malonate and aldehydes has been developed to furnish spiroheterocyclic tetrahydropyrans in high yields with greater than 95:5 d.r. This method is practical, in that 36 examples, including a range of aldehydes and exo-vinyl heterocycles, are presented. By applying the newly developed method, the total synthesis of (+)-broussonetine G and formal synthesis of (+)-broussonetine H were achieved in a concise way.
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Affiliation(s)
- Li Zhou
- The State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, CAS, University of Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, China
| | - Shu-Yang Yu
- The State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, CAS, University of Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, China
| | - Yong Tang
- The State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, CAS, University of Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, China
| | - Lijia Wang
- The State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, CAS, University of Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032, China.,School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Rd., Shanghai, 200241, China
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9
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Zhou L, Yu S, Tang Y, Wang L. Facile Stereoselective Approach to Diverse Spiroheterocyclic Tetrahydropyrans: Concise Synthesis of (+)‐Broussonetine G and H. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201907353] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Li Zhou
- The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry, CAS University of Chinese Academy of Sciences 345 Lingling Lu Shanghai 200032 China
| | - Shu‐Yang Yu
- The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry, CAS University of Chinese Academy of Sciences 345 Lingling Lu Shanghai 200032 China
| | - Yong Tang
- The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry, CAS University of Chinese Academy of Sciences 345 Lingling Lu Shanghai 200032 China
| | - Lijia Wang
- The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry, CAS University of Chinese Academy of Sciences 345 Lingling Lu Shanghai 200032 China
- School of Chemistry and Molecular Engineering East China Normal University 500 Dongchuan Rd. Shanghai 200241 China
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10
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Gai S, Lucas NT, Hawkins BC. Benzannulated 6,5-Spiroketals from Donor–Acceptor Cyclopropanes. Org Lett 2019; 21:2872-2875. [DOI: 10.1021/acs.orglett.9b00878] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Sinan Gai
- Department of Chemistry, University of Otago, Dunedin 9054, New Zealand
| | - Nigel T. Lucas
- Department of Chemistry, University of Otago, Dunedin 9054, New Zealand
| | - Bill C. Hawkins
- Department of Chemistry, University of Otago, Dunedin 9054, New Zealand
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11
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Gupta S, Xie P, Xia Y, Lee D. Reactivity of arynes toward functionalized alkenes: intermolecular Alder-ene vs. addition reactions. Org Chem Front 2018. [DOI: 10.1039/c8qo00470f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The selectivity between two different manifolds of reactions of arynes reacting with functionalized alkenes is described.
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Affiliation(s)
- Saswata Gupta
- Department of Chemistry
- University of Illinois at Chicago
- Chicago
- USA
| | - Peipei Xie
- College of Chemistry and Materials Engineering
- Wenzhou University
- Wenzhou
- P.R. China
| | - Yuanzhi Xia
- College of Chemistry and Materials Engineering
- Wenzhou University
- Wenzhou
- P.R. China
| | - Daesung Lee
- Department of Chemistry
- University of Illinois at Chicago
- Chicago
- USA
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12
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Subba Reddy BV, Nair PN, Antony A, Srivastava N. Recent Advances in Prins Spirocyclization. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700633] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- B. V. Subba Reddy
- Centre for Semio Chemicals; CSIR - Indian Institute of Chemical Technology; Hyderabad India
| | - Preethi Narayanan Nair
- Centre for Semio Chemicals; CSIR - Indian Institute of Chemical Technology; Hyderabad India
| | - Aneesh Antony
- Centre for Semio Chemicals; CSIR - Indian Institute of Chemical Technology; Hyderabad India
| | - Nikhil Srivastava
- Centre for Semio Chemicals; CSIR - Indian Institute of Chemical Technology; Hyderabad India
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13
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Yu G, Clive DLJ. Formation of meta-Substituted Phenols by Transition Metal-Free Aromatization: Use of 2-Bromocyclohex-2-en-1-ones. J Org Chem 2016; 81:8470-84. [PMID: 27563935 DOI: 10.1021/acs.joc.6b01653] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Addition of Grignard or other organometallic reagents to 2-halocyclohex-2-en-1-ones bearing an alkyl or aryl group at C-5, followed by mild acid treatment and exposure to 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) at room temperature, generates meta-substituted phenols in which the newly introduced meta substituent originates from the Grignard reagent. The range of effective organometallic reagents includes alkyl, allyl, alkynyl, aryl, and heteroaryl compounds including those with fluorine substituents. The initial halocyclohexenone can be deprotonated at C-6 and reacted with carbon, fluorine, or sulfur electrophiles before the Grignard addition so as to generate highly substituted phenols.
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Affiliation(s)
- Guojun Yu
- Chemistry Department, University of Alberta , Edmonton, Alberta T6G 2G2, Canada
| | - Derrick L J Clive
- Chemistry Department, University of Alberta , Edmonton, Alberta T6G 2G2, Canada
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14
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Li J, Peng H, Wang F, Wang X, Jiang H, Yin B. 2,5-Oxyarylation of Furans: Synthesis of Spiroacetals via Palladium-Catalyzed Aerobic Oxidative Coupling of Boronic Acids with α-Hydroxyalkylfurans. Org Lett 2016; 18:3226-9. [DOI: 10.1021/acs.orglett.6b01472] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jiuyi Li
- School of Chemistry and Chemical
Engineering, South China University of Technology, Guangzhou 510641, China
| | - Hui Peng
- School of Chemistry and Chemical
Engineering, South China University of Technology, Guangzhou 510641, China
| | - Furong Wang
- School of Chemistry and Chemical
Engineering, South China University of Technology, Guangzhou 510641, China
| | - Xiujun Wang
- School of Chemistry and Chemical
Engineering, South China University of Technology, Guangzhou 510641, China
| | - Huanfeng Jiang
- School of Chemistry and Chemical
Engineering, South China University of Technology, Guangzhou 510641, China
| | - Biaolin Yin
- School of Chemistry and Chemical
Engineering, South China University of Technology, Guangzhou 510641, China
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15
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Xue J, Zhang H, Tian T, Yin K, Liu D, Jiang X, Li Y, Jin X, Yao X. Organohalogenite-Catalyzed Spiroketalization: Enantioselective Synthesis of Bisbenzannulated Spiroketal Cores. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201500390] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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16
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Subba Reddy BV, Hanuman Reddy V, Medaboina D, Sridhar B, Rami Reddy YV. A tandem Prins spirocyclization for the stereoselective synthesis of tetrahydrospiro[chroman-2,4′-pyran] derivatives. Org Biomol Chem 2016; 14:3234-7. [DOI: 10.1039/c5ob02639c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel cascade process has been developed for the synthesis of tetrahydrospiro[chroman-2,4′-pyran] derivatives by condensation of aldehydes with 2-(5-hydroxy-3-methylenepentyl)phenols using BF3·OEt2 under mild reaction conditions.
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Affiliation(s)
- B. V. Subba Reddy
- Natural Product Chemistry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - V. Hanuman Reddy
- Natural Product Chemistry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
- Department of Chemistry
| | | | - B. Sridhar
- Laboratory of X-ray Crystallography
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
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17
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Atkinson DJ, Brimble MA. Isolation, biological activity, biosynthesis and synthetic studies towards the rubromycin family of natural products. Nat Prod Rep 2015; 32:811-40. [DOI: 10.1039/c4np00153b] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The rubromycins are a unique family of natural products. This review covers their isolation, biological activity, biosynthesis and a detailed discussion of the diverse chemistry employed for total synthesis.
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Affiliation(s)
- Darcy J. Atkinson
- School of Chemical Sciences, The University of Auckland
- Auckland
- New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland
- Auckland
| | - Margaret A. Brimble
- School of Chemical Sciences, The University of Auckland
- Auckland
- New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland
- Auckland
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18
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Sharma I, Wurst JM, Tan DS. Solvent-dependent divergent functions of Sc(OTf)₃ in stereoselective epoxide-opening spiroketalizations. Org Lett 2014; 16:2474-7. [PMID: 24742081 PMCID: PMC4018158 DOI: 10.1021/ol500853q] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
![]()
A stereocontrolled
synthesis of benzannulated spiroketals has been
developed using solvent-dependent Sc(OTf)3-mediated spirocyclizations
of exo-glycal epoxides having alcohol side chains.
In THF, the reaction proceeds via Lewis acid catalysis under kinetic
control with inversion of configuration at the anomeric carbon. In
contrast, in CH2Cl2, Brønsted acid catalysis
under thermodynamic control leads to retention of configuration. The
reactions accommodate a variety of aryl substituents and ring sizes
and provide stereochemically diverse spiroketals.
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Affiliation(s)
- Indrajeet Sharma
- Molecular Pharmacology & Chemistry Program, ‡Tri-Institutional PhD Program in Chemical Biology, and Tri-Institutional Research Program, Memorial Sloan Kettering Cancer Center , 1275 York Avenue, Box 422, New York, New York 10065, United States
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19
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Synthesis of 5,6- and 6,6-Spirocyclic Compounds. SYNTHESIS OF SATURATED OXYGENATED HETEROCYCLES I 2014. [DOI: 10.1007/978-3-642-41473-2_5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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20
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Peng Y, Xu XB, Xiao J, Wang YW. Nickel-mediated stereocontrolled synthesis of spiroketals via tandem cyclization–coupling of β-bromo ketals and aryl iodides. Chem Commun (Camb) 2014; 50:472-4. [DOI: 10.1039/c3cc47780k] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Liang G, Sharum DT, Lam T, Totah NI. 2-Methylenetetrahydropyrans: efficient partners in the carbonyl ene reaction. Org Lett 2013; 15:5974-7. [PMID: 24215279 PMCID: PMC3946575 DOI: 10.1021/ol402843s] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The carbonyl ene reaction of 2-methylenetetrahydropyrans provides a rapid, high yielding route for the preparation of β-hydroxydihydropyrans under mild conditions. This process provides a new entry for the synthesis of 2-substituted tetrahydropyrans and for the direct introduction of oxygen heterocycles into molecular frameworks.
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Affiliation(s)
- Guohua Liang
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
| | - Dakin T. Sharum
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
| | - Troy Lam
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
| | - Nancy I. Totah
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
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22
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Wang X, Guo P, Wang X, Wang Z, Ding K. Practical Asymmetric Catalytic Synthesis of Spiroketals and Chiral Diphosphine Ligands. Adv Synth Catal 2013. [DOI: 10.1002/adsc.201300380] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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23
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Kalpogiannaki D, Martini CI, Nikopoulou A, Nyxas JA, Pantazi V, Hadjiarapoglou LP. Fused dihydrofurans from the one-pot, three-component reaction of 1,3-cyclohexanedione, iodobenzene diacetate and alkenes. Tetrahedron 2013. [DOI: 10.1016/j.tet.2012.12.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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24
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Aitken HRM, Furkert DP, Hubert JG, Wood JM, Brimble MA. Enantioselective access to benzannulated spiroketals using a chiral sulfoxide auxiliary. Org Biomol Chem 2013; 11:5147-55. [DOI: 10.1039/c3ob41065j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Chang S, Britton R. Enantioselective synthesis of spiroacetals via silver(I)-promoted alkylation of hemiacetals: total synthesis of cephalosporolides E and F. Org Lett 2012; 14:5844-7. [PMID: 23145960 DOI: 10.1021/ol302694s] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A silver(I)-promoted intramolecular hemiacetal alkylation has been developed that converts readily available keto-chlorodiols into functionalized spiroacetals containing 5,5-, 5,6-, and 5,7-membered ring systems. The efficiency of this process is demonstrated in a concise total synthesis of the fungal metabolites cephalosporolides E and F.
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Affiliation(s)
- Stanley Chang
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, Canada
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26
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Butkevich AN, Corbu A, Meerpoel L, Stansfield I, Angibaud P, Bonnet P, Cossy J. Two-Step One-Pot Synthesis of Benzoannulated Spiroacetals by Suzuki–Miyaura Coupling/Acid-Catalyzed Spiroacetalization. Org Lett 2012; 14:4998-5001. [DOI: 10.1021/ol302088w] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alexey N. Butkevich
- Laboratoire de Chimie Organique, ESPCI ParisTech, CNRS, 10 rue Vauquelin, 75231 Paris Cedex 05, France, Janssen Research & Development, Division of Janssen-Cilag S.A., Oncology and Medicinal Chemistry, Campus de Maigremont, 27106 Val de Reuil, Cedex, France, and Janssen Research & Development, Division of Janssen Pharmaceutica N.V., Turnhoutsweg 30, 2340 Beerse, Belgium
| | - Andrei Corbu
- Laboratoire de Chimie Organique, ESPCI ParisTech, CNRS, 10 rue Vauquelin, 75231 Paris Cedex 05, France, Janssen Research & Development, Division of Janssen-Cilag S.A., Oncology and Medicinal Chemistry, Campus de Maigremont, 27106 Val de Reuil, Cedex, France, and Janssen Research & Development, Division of Janssen Pharmaceutica N.V., Turnhoutsweg 30, 2340 Beerse, Belgium
| | - Lieven Meerpoel
- Laboratoire de Chimie Organique, ESPCI ParisTech, CNRS, 10 rue Vauquelin, 75231 Paris Cedex 05, France, Janssen Research & Development, Division of Janssen-Cilag S.A., Oncology and Medicinal Chemistry, Campus de Maigremont, 27106 Val de Reuil, Cedex, France, and Janssen Research & Development, Division of Janssen Pharmaceutica N.V., Turnhoutsweg 30, 2340 Beerse, Belgium
| | - Ian Stansfield
- Laboratoire de Chimie Organique, ESPCI ParisTech, CNRS, 10 rue Vauquelin, 75231 Paris Cedex 05, France, Janssen Research & Development, Division of Janssen-Cilag S.A., Oncology and Medicinal Chemistry, Campus de Maigremont, 27106 Val de Reuil, Cedex, France, and Janssen Research & Development, Division of Janssen Pharmaceutica N.V., Turnhoutsweg 30, 2340 Beerse, Belgium
| | - Patrick Angibaud
- Laboratoire de Chimie Organique, ESPCI ParisTech, CNRS, 10 rue Vauquelin, 75231 Paris Cedex 05, France, Janssen Research & Development, Division of Janssen-Cilag S.A., Oncology and Medicinal Chemistry, Campus de Maigremont, 27106 Val de Reuil, Cedex, France, and Janssen Research & Development, Division of Janssen Pharmaceutica N.V., Turnhoutsweg 30, 2340 Beerse, Belgium
| | - Pascal Bonnet
- Laboratoire de Chimie Organique, ESPCI ParisTech, CNRS, 10 rue Vauquelin, 75231 Paris Cedex 05, France, Janssen Research & Development, Division of Janssen-Cilag S.A., Oncology and Medicinal Chemistry, Campus de Maigremont, 27106 Val de Reuil, Cedex, France, and Janssen Research & Development, Division of Janssen Pharmaceutica N.V., Turnhoutsweg 30, 2340 Beerse, Belgium
| | - Janine Cossy
- Laboratoire de Chimie Organique, ESPCI ParisTech, CNRS, 10 rue Vauquelin, 75231 Paris Cedex 05, France, Janssen Research & Development, Division of Janssen-Cilag S.A., Oncology and Medicinal Chemistry, Campus de Maigremont, 27106 Val de Reuil, Cedex, France, and Janssen Research & Development, Division of Janssen Pharmaceutica N.V., Turnhoutsweg 30, 2340 Beerse, Belgium
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27
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Green JC, Burnett GL, Pettus TRR. New strategies for natural products containing chroman spiroketals. ACTA ACUST UNITED AC 2012; 84:1621-1631. [PMID: 25554712 DOI: 10.1351/pac-con-11-10-34] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Two cycloaddition strategies are described that lead to various chroman spiroketals from assorted exocyclic enol ethers. Unlike conventional thermodynamic ketalization strategies, the stereochemical outcome for this approach is determined by a kinetic cycloaddition reaction. Thus, the stereochemical outcome reflects the olefin geometry of the starting materials along with the orientation of the associated transition state. However, the initial kinetic product can also be equilibrated by acid catalysis and reconstituted into a thermodynamic stereochemical arrangement. Thus, these strategies uniquely enable synthetic access to either the thermodynamic or kinetic conformation of the spiroketal stereocenter itself. Applications of these strategies in the syntheses of berkelic acid, β-rubromycin, and paecilospirone are presented along with the use of a chroman spiroketal for the construction of heliespirones A and C.
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Affiliation(s)
- Jason C Green
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, CA 93106-9510, USA
| | - G Leslie Burnett
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, CA 93106-9510, USA
| | - Thomas R R Pettus
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, CA 93106-9510, USA
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28
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Li X, Xue J, Huang C, Li Y. Copper(I)-Catalyzed Hydroalkoxylation/Hydrogen-Bonding-Induced Asymmetric Hetero-Diels-Alder Cycloaddition Cascade: An Approach to Aromatic Spiroketals. Chem Asian J 2012; 7:903-6. [DOI: 10.1002/asia.201101056] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Indexed: 11/10/2022]
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29
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Wang X, Han Z, Wang Z, Ding K. Catalytic Asymmetric Synthesis of Aromatic Spiroketals by SpinPhox/Iridium(I)-Catalyzed Hydrogenation and Spiroketalization of α,α′-Bis(2-hydroxyarylidene) Ketones. Angew Chem Int Ed Engl 2011; 51:936-40. [DOI: 10.1002/anie.201106488] [Citation(s) in RCA: 208] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Indexed: 11/06/2022]
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30
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Wang X, Han Z, Wang Z, Ding K. Catalytic Asymmetric Synthesis of Aromatic Spiroketals by SpinPhox/Iridium(I)-Catalyzed Hydrogenation and Spiroketalization of α,α′-Bis(2-hydroxyarylidene) Ketones. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201106488] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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31
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Bandichhor R, Lowell AN, Kozlowski MC. Alternative spiroketalization methods toward purpuromycin: a hemiketal conjugate addition strategy and use of an electron-rich isocoumarin precursor. J Org Chem 2011; 76:6475-87. [PMID: 21707092 DOI: 10.1021/jo200398v] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Two methods are presented that were designed to circumvent the persistent problem of benzofuran formation and instead yield a spiroketal of the rubromycin family type. First, using an alternative disconnection, a hemiketal conjugate addition to a naphthaquinone electrophile was investigated. Synthesis of the requisite electrophile provided insight into the selective oxidation and functionalization of the naphthalene portion. Second, the electronic features of the isocoumarin ring system were adjusted, and the corresponding reactivity further supports the hypothesis that electron-rich isocoumarins are capable of spiroketalization. Robust, flexible syntheses from simple precursors were developed that allowed multiple reduced isocoumarins to be generated. Combined, the data presented herein give insight into the sensitivities of this family and illuminate other potential methods of spiroketalization. In addition, the convergent assembly of substrates containing different naphthaquinone and isocoumarin subunits highlights the utility of our 1,3-dipolar cycloaddition approach to generate analogs of these structures for SAR, as well as chemical reactivity studies.
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Affiliation(s)
- Rakeshwar Bandichhor
- Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA
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32
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Wu KL, Mercado EV, Pettus TRR. A Convergent Total Synthesis of (±)-γ-Rubromycin. J Am Chem Soc 2011; 133:6114-7. [DOI: 10.1021/ja1115524] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kun-Liang Wu
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - Eduardo V. Mercado
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - Thomas R. R. Pettus
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
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33
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Duschek A, Kirsch SF. 2-Iodoxybenzoic Acid-A Simple Oxidant with a Dazzling Array of Potential Applications. Angew Chem Int Ed Engl 2011; 50:1524-52. [DOI: 10.1002/anie.201000873] [Citation(s) in RCA: 205] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Indexed: 12/26/2022]
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34
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Duschek A, Kirsch SF. 2-Iodoxybenzoesäure - ein einfaches Oxidationsmittel mit einer Vielfalt an Anwendungsmöglichkeiten. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201000873] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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35
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36
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Sperry J, Wilson ZE, Rathwell DCK, Brimble MA. Isolation, biological activity and synthesis of benzannulated spiroketal natural products. Nat Prod Rep 2010; 27:1117-37. [DOI: 10.1039/b911514p] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Liang G, Bateman LJ, Totah NI. New reactions of 2-methylenetetrahydropyrans. A three component coupling protocol for the synthesis of tetrahydropyranyl ketides. Chem Commun (Camb) 2009:6457-9. [PMID: 19841808 PMCID: PMC4335680 DOI: 10.1039/b916190b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three component coupling of a 2-methylenetetrahydropyran, an activated aldehyde or ketone and a secondary nucleophile provides an efficient preparation of tetrahydropyranyl ketides, a unit common to many complex natural products.
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Affiliation(s)
- Guohua Liang
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, USA
| | - Laura J. Bateman
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, USA
| | - Nancy I. Totah
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, USA
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38
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Rathwell D, Yang SH, Tsang K, Brimble M. An Efficient Formal Synthesis of the Human Telomerase Inhibitor (±)-γ-Rubromycin. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200903316] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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39
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Rathwell D, Yang SH, Tsang K, Brimble M. An Efficient Formal Synthesis of the Human Telomerase Inhibitor (±)-γ-Rubromycin. Angew Chem Int Ed Engl 2009; 48:7996-8000. [DOI: 10.1002/anie.200903316] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Liu G, Wurst JM, Tan DS. Stereoselective synthesis of benzannulated spiroketals: influence of the aromatic ring on reactivity and conformation. Org Lett 2009; 11:3670-3. [PMID: 19634891 PMCID: PMC2760470 DOI: 10.1021/ol901437f] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A systematic stereocontrolled synthesis of benzannulated spiroketals has been developed, using kinetic spirocyclization reactions of glycal epoxides, leading to a new AcOH-induced cyclization and valuable insights into the reactivity and conformations of these systems. One stereochemical series accommodates axial positioning of the aromatic ring while another adopts an alternative (1)C(4) chair conformation to avoid it. Equatorial aromatic rings also participate in nonobvious steric interactions that impact thermodynamic stability. A discovery library of 68 benzannulated spiroketals with systematic variations in stereochemistry, ring size, and positioning of the aromatic substituent has been synthesized for broad biological evaluation.
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Affiliation(s)
- Guodong Liu
- Molecular Pharmacology & Chemistry Program, Memorial Sloan–Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065
| | - Jacqueline M. Wurst
- Tri-Institutional Training Program in Chemical Biology, and Tri-Institutional Research Program, Memorial Sloan–Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065
| | - Derek S. Tan
- Molecular Pharmacology & Chemistry Program, Memorial Sloan–Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065
- Tri-Institutional Training Program in Chemical Biology, and Tri-Institutional Research Program, Memorial Sloan–Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065
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41
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Choi PJ, Rathwell DC, Brimble MA. Synthesis of 6,6-bisbenzannulated spiroketals related to the rubromycins using a double intramolecular hetero-Michael addition (DIHMA). Tetrahedron Lett 2009. [DOI: 10.1016/j.tetlet.2009.02.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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42
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Marsini MA, Huang Y, Lindsey CC, Wu KL, Pettus TRR. Diastereoselective syntheses of chroman spiroketals via [4 + 2] cycloaddition of enol ethers and o-quinone methides. Org Lett 2008; 10:1477-80. [PMID: 18336038 DOI: 10.1021/ol8003244] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A variety of chroman spiroketals are synthesized via inverse-demand [4 + 2] cycloaddition of enol ethers and ortho-quinone methides (o-QMs). Low temperature o-QM generation in situ allows for the kinetic, diastereoselective construction of these motifs, providing entry to a number of unusual chroman spiroketal natural products.
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Affiliation(s)
- Maurice A Marsini
- Department of Chemistry and Biochemistry, University of California at Santa Barbara Santa Barbara, California 93106-9510, USA
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43
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Zhou G, Zhu J, Xie Z, Li Y. An Efficient Synthesis of Highly Functionalized [5,6] Aromatic Spiroketals by Hetero-Diels−Alder Reaction. Org Lett 2008; 10:721-4. [PMID: 18266379 DOI: 10.1021/ol7029068] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Guanglian Zhou
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P.R. China
| | - Jianrong Zhu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P.R. China
| | - Zhixiang Xie
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P.R. China
| | - Ying Li
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P.R. China
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44
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Lowell AN, Fennie MW, Kozlowski MC. A Concise Synthesis of the Naphthalene Portion of Purpuromycin. J Org Chem 2008; 73:1911-8. [DOI: 10.1021/jo7024114] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrew N. Lowell
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Michael W. Fennie
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Marisa C. Kozlowski
- Department of Chemistry, Roy and Diana Vagelos Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
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45
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Wu KL, Wilkinson S, Reich NO, Pettus TRR. Facile synthesis of naphthoquinone spiroketals by diastereoselective oxidative [3 + 2] cycloaddition. Org Lett 2007; 9:5537-40. [PMID: 18044909 PMCID: PMC2430727 DOI: 10.1021/ol702450d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A highly selective oxidative [3 + 2] cycloaddition of chiral enol ethers and hydroxynaphthoquinone is described. This convergent strategy is amenable to an enantioselective synthesis of beta-rubromycin and related naphthoquinone spiroketals. Several compounds were found to inhibit DNA-polymerase and telomerase in a manner resembling alpha-rubromycin and beta-rubromycin.
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Affiliation(s)
- Kun-Liang Wu
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106-9510, USA
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46
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Akai S, Kakiguchi K, Nakamura Y, Kuriwaki I, Dohi T, Harada S, Kubo O, Morita N, Kita Y. Total synthesis of (+/-)-gamma-rubromycin on the basis of two aromatic Pummerer-type reactions. Angew Chem Int Ed Engl 2007; 46:7458-61. [PMID: 17702074 DOI: 10.1002/anie.200702382] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Shuji Akai
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6, Yamada-oka, Suita, Osaka 565-0871, Japan
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47
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Akai S, Kakiguchi K, Nakamura Y, Kuriwaki I, Dohi T, Harada S, Kubo O, Morita N, Kita Y. Total Synthesis of (±)-γ-Rubromycin on the Basis of Two Aromatic Pummerer-Type Reactions. Angew Chem Int Ed Engl 2007. [DOI: 10.1002/ange.200702382] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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48
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Brasholz M, Sörgel S, Azap C, Reißig H. Rubromycins: Structurally Intriguing, Biologically Valuable, Synthetically Challenging Antitumour Antibiotics. European J Org Chem 2007. [DOI: 10.1002/ejoc.200601054] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Malte Brasholz
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany, Fax: +49‐30‐838‐55367
| | - Sebastian Sörgel
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany, Fax: +49‐30‐838‐55367
| | - Cengiz Azap
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany, Fax: +49‐30‐838‐55367
| | - Hans‐Ulrich Reißig
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany, Fax: +49‐30‐838‐55367
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49
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Synthesis of aromatic spiroacetals related to γ-rubromycin based on a 3H-spiro[1-benzofuran-2,2′-chromane] skeleton. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.02.033] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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50
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Takeda N, Miyata O, Naito T. Efficient Synthesis of Benzofurans Utilizing [3,3]-Sigmatropic Rearrangement Triggered byN-Trifluoroacetylation of Oxime Ethers: Short Synthesis of Natural 2-Arylbenzofurans. European J Org Chem 2007. [DOI: 10.1002/ejoc.200601001] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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