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Xiao JX, Li FX, Ren SJ, Qu J. Studies on the Biomimetic Synthesis of Marine Ladder Polyethers via Endo-Selective Epoxide-to-Epoxonium Ring-Opening Cascades. Angew Chem Int Ed Engl 2024; 63:e202403597. [PMID: 38752455 DOI: 10.1002/anie.202403597] [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: 02/21/2024] [Indexed: 07/16/2024]
Abstract
Marine ladder polyethers have attracted the attention of chemists and biologists because of their potent biological activities. Synthetic chemists have attempted to construct their polyether frameworks by epoxide ring-opening cascades, as Nakanishi hypothesis describes. However, Baldwin's rules of ring closure state that exo-selective intramolecular cyclization of epoxy alcohols is preferred over endo-selective cyclization. Herein, we investigated epoxide ring-opening cascades of polyepoxy alcohols in [EMIM]BF4/PFTB (1-ethyl-3-methylimidazolium tetrafluoroborate /perfluoro-tert-butyl alcohol) and found that all-endo products were formed via epoxide-to-epoxonium ring-opening cyclizations (not restricted by Baldwin's rules, which only apply to intramolecular hydroxyl-to-epoxide cyclizations). We determined that the key factor enabling polyepoxy alcohols to undergo a high proportion of all-endo-selective cyclization was inhibition of exo-selective hydroxyl-to-epoxide cyclization starting from the terminal hydroxyl group of a polyepoxy alcohol. By introducing a slow-release protecting group to the terminal hydroxyl group, we could markedly increase the cyclization yields of polyether fragments with hydrogen atoms at the ring junctions. For the first time, we constructed consecutively fused six-membered-ring and fused seven-, eight-, and nine-membered-ring polyether fragments by epoxide-to-epoxonium ring-opening cyclizations through the addition of a suitable Lewis acid. We also suggest that the biosynthesis of marine ladder polyethers may proceed via epoxide-to-epoxonium ring-opening cyclization of polyepoxide.
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Affiliation(s)
- Jia-Xi Xiao
- College of Chemistry, Nankai University, The State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China
| | - Feng-Xing Li
- College of Chemistry, Nankai University, The State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China
| | - Shu-Jian Ren
- College of Chemistry, Nankai University, The State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China
| | - Jin Qu
- College of Chemistry, Nankai University, The State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China
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2
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Chintalapudi V, Wilson C, Clark JS. Synthesis of the I-K Fused Polyether Array of CTX3C and Related Ciguatoxins by Use of a Gold-Catalyzed Cyclization Reaction. Org Lett 2024; 26:775-780. [PMID: 38238251 PMCID: PMC10845158 DOI: 10.1021/acs.orglett.3c03782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/04/2024] [Accepted: 01/15/2024] [Indexed: 02/03/2024]
Abstract
The I-K fragment (C31-C49) of the ciguatoxin CTX3C has been synthesized from a simple chiral pool derived tetrahydropyranyl alcohol. An efficient gold-catalyzed cyclization reaction of a γ'-hydroxy ynone has been used to accomplish efficient closure of ring K under mild conditions. The resulting vinylogous ester has been elaborated to give a complete tricyclic fragment bearing the dimethyl-substituted side chain required for assembly of the LM spirocyclic acetal portion of the target.
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Affiliation(s)
| | - Claire Wilson
- School of Chemistry, Joseph
Black Building, University of Glasgow, University Avenue, Glasgow, G12 8QQ, U.K.
| | - J. Stephen Clark
- School of Chemistry, Joseph
Black Building, University of Glasgow, University Avenue, Glasgow, G12 8QQ, U.K.
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3
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Triantafyllakis M, Alexander S, Woolford S, Wilson C, Clark JS. Synthesis of the A-F Fragment of the Pacific Ciguatoxin CTX3C by Iterative Ring-Closing Metathesis and Tsuji-Trost Allylation. Chemistry 2023; 29:e202303121. [PMID: 37830907 PMCID: PMC10946863 DOI: 10.1002/chem.202303121] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 10/12/2023] [Accepted: 10/13/2023] [Indexed: 10/14/2023]
Abstract
The fully functionalized A-F fragment of the Pacific ciguatoxin CTX3C has been synthesized from a derivative of D-glucal, which serves as the B-ring. Rings A and C were introduced to either side of ring B by ring-closing diene and enyne metathesis (RCM). The seven-membered D-ring and eight-membered E-ring were assembled by iterative use of a six-step reaction sequence in which RCM was used for ring construction and Tsuji-Trost allylation was employed for subsequent stereoselective functionalization. The nine-membered F-ring was formed by use of an RCM reaction and bears the functionality required for attachment of the I-M fragment and subsequent closure of rings G and H.
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Affiliation(s)
- Myron Triantafyllakis
- School of ChemistryJoseph Black BuildingUniversity of GlasgowUniversity AvenueGlasgowG12 8QQUK
| | - Sam Alexander
- School of ChemistryJoseph Black BuildingUniversity of GlasgowUniversity AvenueGlasgowG12 8QQUK
| | - Sophie Woolford
- School of ChemistryJoseph Black BuildingUniversity of GlasgowUniversity AvenueGlasgowG12 8QQUK
| | - Claire Wilson
- School of ChemistryJoseph Black BuildingUniversity of GlasgowUniversity AvenueGlasgowG12 8QQUK
| | - J. Stephen Clark
- School of ChemistryJoseph Black BuildingUniversity of GlasgowUniversity AvenueGlasgowG12 8QQUK
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Wang H, Liu Y, Zhang H, Yang B, He H, Gao S. Asymmetric Total Synthesis of Cephalotaxus Diterpenoids: Cephinoid P, Cephafortoid A, 14- epi-Cephafortoid A and Fortalpinoids M-N, P. J Am Chem Soc 2023; 145:16988-16994. [PMID: 37493585 DOI: 10.1021/jacs.3c05455] [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: 07/27/2023]
Abstract
The asymmetric total syntheses of cephalotaxus C19 diterpenoids, bearing a unique cycloheptene A ring with a chiral methyl group at C-12, were disclosed based on a universal strategy. Six members, including cephinoid P, cephafortoid A, 14-epi-cephafortoid A and fortalpinoids M-N, P, were accomplished for the first time. The concise approach relies on two crucial steps: (1) a Nicholas/Hosomi-Sakurai cascade reaction was developed to efficiently generate the cycloheptene ring bearing a chiral methyl group; (2) an intramolecular Pauson-Khand reaction was followed to facilitate the construction of the complete skeleton of target molecules. Our studies provide a new strategy for the synthetic analysis of cephalotaxus diterpenoids and structurally related polycyclic natural products.
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Affiliation(s)
- Hui Wang
- State Key Laboratory of Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Yi Liu
- State Key Laboratory of Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Hongyuan Zhang
- State Key Laboratory of Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Baochao Yang
- State Key Laboratory of Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Haibing He
- State Key Laboratory of Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China
| | - Shuanhu Gao
- State Key Laboratory of Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Shanghai Frontiers Science Center of Molecule Intelligent Syntheses, School of Chemistry and Molecular Engineering, Wuhu Hospital Affiliated to East China Normal University, East China Normal University, Shanghai 200062, P. R. China
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5
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Loeffler CR, Tartaglione L, Friedemann M, Spielmeyer A, Kappenstein O, Bodi D. Ciguatera Mini Review: 21st Century Environmental Challenges and the Interdisciplinary Research Efforts Rising to Meet Them. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:3027. [PMID: 33804281 PMCID: PMC7999458 DOI: 10.3390/ijerph18063027] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 12/19/2022]
Abstract
Globally, the livelihoods of over a billion people are affected by changes to marine ecosystems, both structurally and systematically. Resources and ecosystem services, provided by the marine environment, contribute nutrition, income, and health benefits for communities. One threat to these securities is ciguatera poisoning; worldwide, the most commonly reported non-bacterial seafood-related illness. Ciguatera is caused by the consumption of (primarily) finfish contaminated with ciguatoxins, potent neurotoxins produced by benthic single-cell microalgae. When consumed, ciguatoxins are biotransformed and can bioaccumulate throughout the food-web via complex pathways. Ciguatera-derived food insecurity is particularly extreme for small island-nations, where fear of intoxication can lead to fishing restrictions by region, species, or size. Exacerbating these complexities are anthropogenic or natural changes occurring in global marine habitats, e.g., climate change, greenhouse-gas induced physical oceanic changes, overfishing, invasive species, and even the international seafood trade. Here we provide an overview of the challenges and opportunities of the 21st century regarding the many facets of ciguatera, including the complex nature of this illness, the biological/environmental factors affecting the causative organisms, their toxins, vectors, detection methods, human-health oriented responses, and ultimately an outlook towards the future. Ciguatera research efforts face many social and environmental challenges this century. However, several future-oriented goals are within reach, including digital solutions for seafood supply chains, identifying novel compounds and methods with the potential for advanced diagnostics, treatments, and prediction capabilities. The advances described herein provide confidence that the tools are now available to answer many of the remaining questions surrounding ciguatera and therefore protection measures can become more accurate and routine.
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Affiliation(s)
- Christopher R. Loeffler
- National Reference Laboratory of Marine Biotoxins, Department Safety in the Food Chain, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany; (A.S.); (O.K.); (D.B.)
- Department of Pharmacy, School of Medicine and Surgery, University of Napoli Federico II, Via D. Montesano 49, 80131 Napoli, Italy;
| | - Luciana Tartaglione
- Department of Pharmacy, School of Medicine and Surgery, University of Napoli Federico II, Via D. Montesano 49, 80131 Napoli, Italy;
- CoNISMa—National Inter-University Consortium for Marine Sciences, Piazzale Flaminio 9, 00196 Rome, Italy
| | - Miriam Friedemann
- Department Exposure, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany;
| | - Astrid Spielmeyer
- National Reference Laboratory of Marine Biotoxins, Department Safety in the Food Chain, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany; (A.S.); (O.K.); (D.B.)
| | - Oliver Kappenstein
- National Reference Laboratory of Marine Biotoxins, Department Safety in the Food Chain, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany; (A.S.); (O.K.); (D.B.)
| | - Dorina Bodi
- National Reference Laboratory of Marine Biotoxins, Department Safety in the Food Chain, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589 Berlin, Germany; (A.S.); (O.K.); (D.B.)
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6
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Stereoselective Synthesis of the I-L Fragment of the Pacific Ciguatoxins. Toxins (Basel) 2020; 12:toxins12120740. [PMID: 33255410 PMCID: PMC7760828 DOI: 10.3390/toxins12120740] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/20/2020] [Accepted: 11/20/2020] [Indexed: 11/17/2022] Open
Abstract
The I-L ring system found in all the Pacific ciguatoxins has been prepared from a tricyclic precursor in a highly stereoselective manner. Subtle differences in the reactivity of the enones present in the seven- and eight-membered rings of the tricyclic ether starting material have been exploited to allow selective protection of the enone in the eight-membered ring. Subsequent distereoselective allylation of the seven-membered ring has been accomplished by a palladium-mediated Tsuji-Trost reaction. The K-ring methyl and hydroxyl groups have been installed in a highly stereoselective manner by sequential conjugate reduction and enolate oxidation reactions. Ring L has been constructed by a use of a novel relay ring-closing metathesis reaction to complete the tetracyclic framework, which possesses the functionality necessary for elaboration of rings I and L and the introduction of ring M.
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7
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Popadynec M, Gibbard H, Clark JS. Bidirectional Synthesis of the IJK Fragment of Ciguatoxin CTX3C by Sequential Double Ring-Closing Metathesis and Tsuji-Trost Allylation. Org Lett 2020; 22:3734-3738. [PMID: 32306737 PMCID: PMC7304930 DOI: 10.1021/acs.orglett.0c01238] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
![]()
A novel four-step bidirectional strategy
has been used to synthesize
the IJK fragment of the marine polyether natural product CTX3C from
a simple monocyclic precursor in a concise and efficient manner. The
four-step bidirectional sequence involves ring-closing metathesis,
alcohol oxidation, enol carbonate formation, and palladium-mediated
Tsuji–Trost allylation.
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Affiliation(s)
- Michael Popadynec
- School of Chemistry, Joseph Black Building, University of Glasgow, University Avenue, Glasgow, G12 8QQ, United Kingdom
| | - Helen Gibbard
- School of Chemistry, Joseph Black Building, University of Glasgow, University Avenue, Glasgow, G12 8QQ, United Kingdom
| | - J Stephen Clark
- School of Chemistry, Joseph Black Building, University of Glasgow, University Avenue, Glasgow, G12 8QQ, United Kingdom
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8
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Elustondo F, Chintalapudi V, Clark JS. A Short Sequence for the Iterative Synthesis of Fused Polyethers. Helv Chim Acta 2019. [DOI: 10.1002/hlca.201900161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Frédéric Elustondo
- School of ChemistryUniversity of Nottingham, University Park Nottingham NG7 2RD United Kingdom
| | - Venkaiah Chintalapudi
- School of Chemistry, Joseph Black BuildingUniversity of Glasgow, University Avenue Glasgow G12 8QQ United Kingdom
| | - J. Stephen Clark
- School of Chemistry, Joseph Black BuildingUniversity of Glasgow, University Avenue Glasgow G12 8QQ United Kingdom
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9
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Oishi T. Design and Synthesis of Artificial Ladder-Shaped Polyethers for Exploring Biological Functions. HETEROCYCLES 2019. [DOI: 10.3987/rev-18-sr(f)1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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10
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Saito T, Fujiwara K, Sano Y, Sato T, Kondo Y, Akiba U, Ishigaki Y, Katoono R, Suzuki T. An improved synthesis of the C42–C52 segment of ciguatoxin 3C. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.02.052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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He H, Qin HB. ZnBr 2-catalyzed direct C-glycosylation of glycosyl acetates with terminal alkynes. Org Chem Front 2018. [DOI: 10.1039/c8qo00380g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
C-Alkynyl glycosides were synthesizedviaZnBr2-catalyzed cross-coupling of glycosyl acetates with terminal alkynes.
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Affiliation(s)
- Haiqing He
- State Key Laboratory of Phytochemistry and Plant Resources in West China
- Kunming Institute of Botany
- Chinese Academy of Sciences
- and Yunnan Key Laboratory of Natural Medicinal Chemistry
- Kunming 650201
| | - Hong-Bo Qin
- State Key Laboratory of Phytochemistry and Plant Resources in West China
- Kunming Institute of Botany
- Chinese Academy of Sciences
- and Yunnan Key Laboratory of Natural Medicinal Chemistry
- Kunming 650201
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12
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Tsou PK, Lee YC, Lankau T, Isobe M, Yu CH. Substituent effects in the Nicholas epimerization of glycosides. J PHYS ORG CHEM 2017. [DOI: 10.1002/poc.3780] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Pei-Kang Tsou
- Department of Chemistry; National Tsing Hua University; Hsinchu Taiwan
| | - Yen-Chun Lee
- Department of Chemistry; National Tsing Hua University; Hsinchu Taiwan
| | - Timm Lankau
- Department of Chemistry; National Tsing Hua University; Hsinchu Taiwan
| | - Minoru Isobe
- Department of Chemistry; National Tsing Hua University; Hsinchu Taiwan
| | - Chin-Hui Yu
- Department of Chemistry; National Tsing Hua University; Hsinchu Taiwan
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13
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Zweig JE, Kim DE, Newhouse TR. Methods Utilizing First-Row Transition Metals in Natural Product Total Synthesis. Chem Rev 2017; 117:11680-11752. [PMID: 28525261 DOI: 10.1021/acs.chemrev.6b00833] [Citation(s) in RCA: 138] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
First-row transition-metal-mediated reactions constitute an important and growing area of research due to the low cost, low toxicity, and exceptional synthetic versatility of these metals. Currently, there is considerable effort to replace existing precious-metal-catalyzed reactions with first-row analogs. More importantly, there are a plethora of unique transformations mediated by first-row metals, which have no classical second- or third-row counterpart. Herein, the application of first-row metal-mediated methods to the total synthesis of natural products is discussed. This Review is intended to highlight strategic uses of these metals to realize efficient syntheses and highlight the future potential of these reagents and catalysts in organic synthesis.
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Affiliation(s)
- Joshua E Zweig
- Department of Chemistry, Yale University , 275 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - Daria E Kim
- Department of Chemistry, Yale University , 275 Prospect Street, New Haven, Connecticut 06520-8107, United States
| | - Timothy R Newhouse
- Department of Chemistry, Yale University , 275 Prospect Street, New Haven, Connecticut 06520-8107, United States
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14
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15
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Szyling J, Franczyk A, Pawluć P, Marciniec B, Walkowiak J. A stereoselective synthesis of (E)- or (Z)-β-arylvinyl halides via a borylative coupling/halodeborylation protocol. Org Biomol Chem 2017; 15:3207-3215. [DOI: 10.1039/c7ob00054e] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A new highly selective method for the synthesis of (E)-arylvinyl iodides and (E)- or (Z)-β-arylvinyl bromides from easily accessible styrenes and vinyl boronates, on the basis of a one-pot procedure via borylative coupling/halodeborylation is reported.
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Affiliation(s)
- Jakub Szyling
- Centre for Advanced Technologies
- Adam Mickiewicz University in Poznan
- 61-614 Poznan
- Poland
- Faculty of Chemistry
| | - Adrian Franczyk
- Centre for Advanced Technologies
- Adam Mickiewicz University in Poznan
- 61-614 Poznan
- Poland
| | - Piotr Pawluć
- Faculty of Chemistry
- Adam Mickiewicz University in Poznan
- 61-614 Poznan
- Poland
| | - Bogdan Marciniec
- Centre for Advanced Technologies
- Adam Mickiewicz University in Poznan
- 61-614 Poznan
- Poland
- Faculty of Chemistry
| | - Jędrzej Walkowiak
- Centre for Advanced Technologies
- Adam Mickiewicz University in Poznan
- 61-614 Poznan
- Poland
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16
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Liu J, Wang L, Zhang J, Xu Z, Ye T. The total synthesis and stereochemical assignment of scytonemin A. Chem Commun (Camb) 2016; 52:1002-5. [PMID: 26593048 DOI: 10.1039/c5cc08324a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The total synthesis of scytonemin A and its C-9 epimer, as well as elucidation of the absolute stereochemistry of natural scytonemin A is described.
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Affiliation(s)
- Junyang Liu
- Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, University Town, Xili, Shenzhen, 518055, China. and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China
| | - Lei Wang
- Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, University Town, Xili, Shenzhen, 518055, China.
| | - Juefei Zhang
- Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, University Town, Xili, Shenzhen, 518055, China.
| | - Zhengshuang Xu
- Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, University Town, Xili, Shenzhen, 518055, China.
| | - Tao Ye
- Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, University Town, Xili, Shenzhen, 518055, China. and Department of Applied Biology & Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, China
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17
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Chen H, Luo X, Qiu S, Sun W, Zhang J. TMSOTf mediated stereoselective synthesis of α-C-glycosides from unactivated aryl acetylenes. Glycoconj J 2016; 34:13-20. [DOI: 10.1007/s10719-016-9718-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/07/2016] [Accepted: 07/18/2016] [Indexed: 01/29/2023]
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18
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Huang KH, Huang CC, Isobe M. Multicomponent Strategy for the Synthesis of Prostaglandin E2 Methyl Ester under Anion Relay Chelation Control. J Org Chem 2016; 81:1571-84. [PMID: 26811990 DOI: 10.1021/acs.joc.5b02735] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Starting with four components, the enantioselective synthesis of prostaglandin E2 methyl ester has been achieved through a highly stereoselective heteroatom-directed conjugate addition reaction and cyclopentanone ring cyclization as the key steps. This asymmetric strategy includes (i) an asymmetric Reformatsky reaction; (ii) conjugate addition of a chiral vinyllithium reagent; (iii) cyclization to form a sulfonylated cyclopentanone in one-pot; followed by (iv) allylation of the side chain. Four carbon-carbon bond-forming processes and three stereogenic centers were established, with the steps from (ii) to (iii) being achieved in a one-pot process.
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Affiliation(s)
- Kuan-Hsun Huang
- Department of Chemistry, National Tsing Hua University , Hsinchu, 30013, Taiwan (ROC)
| | - Chun-Chieh Huang
- Department of Chemistry, National Tsing Hua University , Hsinchu, 30013, Taiwan (ROC)
| | - Minoru Isobe
- Department of Chemistry, National Tsing Hua University , Hsinchu, 30013, Taiwan (ROC)
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19
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Nagumo S, Mizukami M. Cyclization and Ring Transformation via Spirocyclic Arenium Ions. J SYN ORG CHEM JPN 2016. [DOI: 10.5059/yukigoseikyokaishi.74.18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Shinji Nagumo
- Department of Chemistry and Life Science, School of Advanced Engineering, Kogakuin University
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20
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HIRAMA M. Total synthesis and related studies of large, strained, and bioactive natural products. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2016; 92:290-329. [PMID: 27725470 PMCID: PMC5243947 DOI: 10.2183/pjab.92.290] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 08/10/2016] [Indexed: 06/06/2023]
Abstract
Our chemical syntheses and related scientific investigations of natural products with complex architectures and powerful biological activities are described, focusing on the very large 3 nm-long polycyclic ethers called the ciguatoxins, highly strained and labile chromoprotein antitumor antibiotics featuring nine-membered enediyne cores, and extremely potent anthelmintic macrolides called the avermectins.
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Affiliation(s)
- Masahiro HIRAMA
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, Miyagi, Japan
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21
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Yang X, Wu D, Lu Z, Sun H, Li A. A mild preparation of alkynes from alkenyl triflates. Org Biomol Chem 2016; 14:5591-4. [DOI: 10.1039/c6ob00345a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report herein a protocol for preparing alkynes from alkenyl triflates at ambient temperature with LiCl as a promoter.
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Affiliation(s)
- Xiaowen Yang
- Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease and State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- China
- State Key Laboratory of Bioorganic and Natural Products Chemistry
| | - Dimin Wu
- State Key Laboratory of Bioorganic and Natural Products Chemistry
- Collaborative Innovation Center of Chemistry for Life Sciences
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
| | - Zhaohong Lu
- State Key Laboratory of Bioorganic and Natural Products Chemistry
- Collaborative Innovation Center of Chemistry for Life Sciences
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
| | - Hongbin Sun
- Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease and State Key Laboratory of Natural Medicines
- China Pharmaceutical University
- Nanjing 210009
- China
| | - Ang Li
- State Key Laboratory of Bioorganic and Natural Products Chemistry
- Collaborative Innovation Center of Chemistry for Life Sciences
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
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22
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Okutani M, Mori Y. Synthesis of Alkynes from Vinyl Triflates Using Tetrabutylammonium Fluoride. Chem Pharm Bull (Tokyo) 2015; 63:393-6. [DOI: 10.1248/cpb.c15-00146] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | - Yuji Mori
- Faculty of Pharmacy, Meijo University
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23
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Adachi M. Total Synthesis of Polygalolide A by Intramolecular C-Glycosylation. J SYN ORG CHEM JPN 2015. [DOI: 10.5059/yukigoseikyokaishi.73.607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Masaatsu Adachi
- Graduate School of Bioagricultural Sciences, Nagoya University
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24
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Guyon C, Métay E, Popowycz F, Lemaire M. Synthetic applications of hypophosphite derivatives in reduction. Org Biomol Chem 2015; 13:7879-906. [DOI: 10.1039/c5ob01032b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The purpose of this review is to collect the applications in fine synthesis of hypophosphite derivatives as reducing agents.
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Affiliation(s)
- Carole Guyon
- Equipe Catalyse Synthèse Environnement
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- UMR-CNRS 5246
- Université de Lyon
- Université Claude Bernard-Lyon 1
| | - Estelle Métay
- Equipe Catalyse Synthèse Environnement
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- UMR-CNRS 5246
- Université de Lyon
- Université Claude Bernard-Lyon 1
| | - Florence Popowycz
- Equipe Chimie Organique et Bioorganique
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- UMR-CNRS 5246
- Institut National des Sciences Appliquées (INSA Lyon)
- F-69621 Villeurbanne Cedex
| | - Marc Lemaire
- Equipe Catalyse Synthèse Environnement
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
- UMR-CNRS 5246
- Université de Lyon
- Université Claude Bernard-Lyon 1
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25
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Yamashita S, Takeuchi K, Koyama T, Inoue M, Hayashi Y, Hirama M. Practical route to the left wing of CTX1B and total syntheses of CTX1B and 54-deoxyCTX1B. Chemistry 2014; 21:2621-8. [PMID: 25529606 DOI: 10.1002/chem.201405629] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Indexed: 11/07/2022]
Abstract
Ciguatoxins, the principal causative agents of ciguatera seafood poisoning, are extremely large polycyclic ethers. We report herein a reliable route for constructing the left wing of CTX1B, which possesses the acid/base/oxidant-sensitive bisallylic ether moiety, by a 6-exo radical cyclization/ring-closing metathesis strategy. This new route enabled us to achieve the second-generation total synthesis of CTX1B and the first synthesis of 54-deoxyCTX1B.
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Affiliation(s)
- Shuji Yamashita
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578 (Japan).
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26
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Diastereoselective cobalt-assisted Ferrier-type rearrangement to construct chiral alkynyl cyclohexanones. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.09.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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27
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Huang KH, Isobe M. Highly Regioselective Hydrosilylation of Unsymmetric Alkynes Using a Phenylthio Directing Group. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402577] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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28
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29
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Domon D, Fujiwara K, Kawamura N, Katoono R, Kawai H, Suzuki T. A New Variant of Fused Cyclic Ether Synthesis Based on Ireland-Claisen Rearrangement and RCM. Nat Prod Commun 2013. [DOI: 10.1177/1934578x1300800718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A new variant of fused cyclic ether synthesis based on Ireland-Claisen rearrangement and ring-closing olefin metathesis (RCM) was developed. The Ireland-Claisen rearrangement and ring-closing olefin metathesis (RCM) was developed. The Ireland-Claisen rearrangement of a ( Z)-3-alkoxyprop-2-en-1-yl glycolate ester having a cyclic ether on the oxygen at C3 of the ( Z)-prop-2-en-1-yl group stereoselectively produced an anti-α,β-dialkoxyester which was successfully transformed to a fused bicyclic ether via a reaction sequence including RCM.
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Affiliation(s)
- Daisuke Domon
- Department of Chemistry Faculty of Science Hokkaido University Sapporo 606-0810 Japan
| | - Kenshu Fujiwara
- Department of Chemistry Faculty of Science Hokkaido University Sapporo 606-0810 Japan
| | - Natsumi Kawamura
- Department of Chemistry Faculty of Science Hokkaido University Sapporo 606-0810 Japan
| | - Ryo Katoono
- Department of Chemistry Faculty of Science Hokkaido University Sapporo 606-0810 Japan
| | - Hidetoshi Kawai
- Department of Chemistry Faculty of Science Hokkaido University Sapporo 606-0810 Japan
| | - Takanori Suzuki
- Department of Chemistry Faculty of Science Hokkaido University Sapporo 606-0810 Japan
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30
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Yamada H, Adachi M, Isobe M, Nishikawa T. Stereocontrolled total synthesis of polygalolide A. Chem Asian J 2013; 8:1428-35. [PMID: 23670825 DOI: 10.1002/asia.201300362] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Indexed: 11/05/2022]
Abstract
The total synthesis of polygalolide A, a secondary metabolite that was isolated from a Chinese medicinal plant, is reported. A key issue in this synthesis was construction of an oxabicyclo[3.2.1] skeleton, which was solved by the development of an intramolecular Ferrier-type C-glycosylation of a glucal with siloxyfuran as an internal nucleophile. The substrate was prepared from D-glucal by the introduction of trimethylsilylacetylene and siloxyfuran groups. Although C-glycosylation did not occur under the conditions found from model experiments, further examination revealed that the combination of trimethylsilyl trifluoromethanesulfonate (TMSOTf) and 2,4,6-collidine successfully afforded the desired product as a single diastereomer. The siloxy group at the C3 position played a crucial role in the stereocontrol of this reaction. The product was further transformed into a tetracyclic compound as follows: The vinyl ether and acetylenic moieties were reduced and the siloxy group was removed with a Barton-McCombie reaction. The construction of the six-membered ether and the γ-lactone provided the tetracyclic compound. Finally, a phenolic moiety was introduced by using a Mukaiyama aldol reaction to furnish polygalolide A.
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Affiliation(s)
- Hitomi Yamada
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan
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31
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Isobe M. Conjugate addition approach for natural product synthesis inspired by gibberellin and solanoeclepin A targets. PURE APPL CHEM 2013. [DOI: 10.1351/pac-con-12-10-07] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Trimethylzincate is known to react through conjugate addition to α,β-unsaturated ketones, but adds much faster to α,β-unsaturated esters at low temperatures. Since the intermediate zinc enolate behaves differently from that of dimethylcuprate, it offers scope for application in a partial synthesis of gibberellin A3. A second example involving vinylsulfones having an oxygen atom on the γ-carbon strongly directs incoming nucleophiles in conjugate addition mode. Heteroatom-directed conjugate addition (HADCA) provides very reactive carbanion intermediates leading to cyclobutane ring formation, necessary for synthesis of solanoeclepin A. An alternative reaction for the four-membered carbocyclic ring closure was explored to make a bond formation between the propargylic cation of Nicholas type and allyltrimethylsilane nucleophile of Hosomi–Sakurai type. This method allowed a formation of tricyclo[5.2.1.01,6]decene framework.
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Affiliation(s)
- Minoru Isobe
- 1Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang Fu Road, Hsinchu 30013, Taiwan
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32
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33
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Nogoshi K, Domon D, Fujiwara K, Kawamura N, Katoono R, Kawai H, Suzuki T. An Ireland–Claisen rearrangement/RCM based approach for the construction of the EF-ring of ciguatoxin 3C. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2012.12.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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34
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Sakai T, Sugimoto A, Tatematsu H, Mori Y. Divergent synthesis of trans-fused polycyclic ethers by a convergent oxiranyl anion strategy. J Org Chem 2012; 77:11177-91. [PMID: 23214941 DOI: 10.1021/jo302267f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Octacyclic polyethers that correspond to the CDEFGHIJ-ring system of yessotoxin as well as G- and/or I-ring-modified analogues were synthesized in a divergent manner, starting from a common intermediate, using an [X + 2 + Y]-type convergent method. Reaction of a triflate with the oxiranyl anion generated from an epoxy sulfone, followed by ring expansion, allowed for the incorporation of medium-sized ring ethers into the key intermediate. Subsequent acetal formation and reductive etherification afforded various octacycles containing seven- and eight-membered ether rings.
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Affiliation(s)
- Takeo Sakai
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
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35
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Tsao KW, Cheng CY, Isobe M. Cobalt-Mediated Synthesis of the Tricyclo[5.2.1.01,6]decene Framework in Solanoeclepin A. Org Lett 2012; 14:5274-7. [DOI: 10.1021/ol302432d] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kuo-Wei Tsao
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
| | - Chia-Yi Cheng
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
| | - Minoru Isobe
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
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36
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Cheng CY, Isobe M. Three types of products by carbon nucleophiles toward methoxyphenylacetylenic sulfones. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.09.078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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37
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Affiliation(s)
- Masaatsu Adachi
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan, and Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Hitomi Yamada
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan, and Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Minoru Isobe
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan, and Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Toshio Nishikawa
- Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan, and Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan
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38
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Sakai T, Sugimoto A, Mori Y. A Convergent Strategy for the Synthesis of Polycyclic Ethers by Using Oxiranyl Anions. Org Lett 2011; 13:5850-3. [DOI: 10.1021/ol202467z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Takeo Sakai
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Ai Sugimoto
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Yuji Mori
- Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
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39
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40
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Yamashita S, Ishihara Y, Morita H, Uchiyama J, Takeuchi K, Inoue M, Hirama M. Stereoselective 6-exo radical cyclization using cis-vinyl sulfoxide: practical total synthesis of CTX3C. JOURNAL OF NATURAL PRODUCTS 2011; 74:357-364. [PMID: 21250701 DOI: 10.1021/np100729d] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Ciguatoxins, the principal causative toxins of ciguatera seafood poisoning, are large ladder-like polycyclic ethers. We report a highly stereoselective 6-exo radical cyclization/ring-closing olefin metathesis sequence to construct the syn/trans-fused polyether system. The new method was applied to the practical synthesis of ciguatoxin CTX3C.
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Affiliation(s)
- Shuji Yamashita
- Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
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41
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Fuwa H, Suzuki T, Kubo H, Yamori T, Sasaki M. Total synthesis and biological assessment of (-)-exiguolide and analogues. Chemistry 2011; 17:2678-88. [PMID: 21264972 DOI: 10.1002/chem.201003135] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Indexed: 11/06/2022]
Abstract
We describe herein an enantioselective total synthesis of (-)-exiguolide, the natural enantiomer. The methylene bis(tetrahydropyran) substructure was efficiently synthesized by exploiting olefin cross-metathesis for the assembly of readily available acyclic segments and intramolecular oxa-conjugate cyclization and reductive etherification for the formation of the tetrahydropyran rings. The 20-membered macrocyclic framework was constructed in an efficient manner by means of Julia-Kocienski coupling and Yamaguchi macrolactonization. Finally, the (E,Z,E)-triene side chain was introduced stereoselectively via Suzuki-Miyaura coupling to complete the total synthesis. Assessment of the growth inhibitory activity of synthetic (-)-exiguolide against a panel of human cancer cell lines elucidated for the first time that this natural product is an effective antiproliferative agent against the NCI-H460 human lung large cell carcinoma and the A549 human lung adenocarcinoma cell lines. Moreover, we have investigated structure-activity relationships of (-)-exiguolide, which elucidated that the C5-methoxycarbonylmethylidene group and the length of the side chain are important for the potent activity.
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Affiliation(s)
- Haruhiko Fuwa
- Graduate School of Life Sciences, Tohoku University, Aoba-ku, Sendai, Japan.
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42
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Smith JA, Molesworth PP, Hyland CJ, Ryan JH. Seven-Membered Rings. PROGRESS IN HETEROCYCLIC CHEMISTRY 2011. [DOI: 10.1016/s0959-6380(11)22016-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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43
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Six-Membered Ring Systems:. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/s0959-6380(11)22015-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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44
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Silva, Jr. LF, Olofsson B. Hypervalent iodine reagents in the total synthesis of natural products. Nat Prod Rep 2011; 28:1722-54. [DOI: 10.1039/c1np00028d] [Citation(s) in RCA: 247] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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45
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Fuwa H. Total Synthesis of Structurally Complex Marine Oxacyclic Natural Products. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2010. [DOI: 10.1246/bcsj.20100209] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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46
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Ortega N, Martín VS, Martín T. An Approach to Lauroxanes by Iterative Use of Co2(CO)6-Acetylenic Complexes. A Formal Synthesis of (+)-Laurencin. J Org Chem 2010; 75:6660-72. [DOI: 10.1021/jo101566x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nuria Ortega
- Departamento de Química Orgánica, Instituto Universitario de Bioorgánica “Antonio González”, Universidad de La Laguna, Astrofísico Francisco Sánchez 2, 38206 La Laguna, Tenerife, Islas Canarias, Spain
| | - Victor S. Martín
- Departamento de Química Orgánica, Instituto Universitario de Bioorgánica “Antonio González”, Universidad de La Laguna, Astrofísico Francisco Sánchez 2, 38206 La Laguna, Tenerife, Islas Canarias, Spain
| | - Tomás Martín
- Departamento de Química Orgánica, Instituto Universitario de Bioorgánica “Antonio González”, Universidad de La Laguna, Astrofísico Francisco Sánchez 2, 38206 La Laguna, Tenerife, Islas Canarias, Spain
- Instituto de Productos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, Astrofísico Francisco Sánchez 3, 38206 La Laguna, Tenerife, Islas Canarias, Spain
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47
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Hayashi Y, Yamaguchi H, Toyoshima M, Okado K, Toyo T, Shoji M. Formal Total Synthesis of Fostriecin by 1,4-Asymmetric Induction with an Alkyne-Cobalt Complex. Chemistry 2010; 16:10150-9. [DOI: 10.1002/chem.201000795] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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48
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Albrecht Ł, Jiang H, Dickmeiss G, Gschwend B, Hansen SG, Jørgensen KA. Asymmetric Formal trans-Dihydroxylation and trans-Aminohydroxylation of α,β-Unsaturated Aldehydes via an Organocatalytic Reaction Cascade. J Am Chem Soc 2010; 132:9188-96. [DOI: 10.1021/ja103538s] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Łukasz Albrecht
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Hao Jiang
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Gustav Dickmeiss
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Björn Gschwend
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Signe Grann Hansen
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Karl Anker Jørgensen
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
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Caillaud A, de la Iglesia P, Darius HT, Pauillac S, Aligizaki K, Fraga S, Chinain M, Diogène J. Update on methodologies available for ciguatoxin determination: perspectives to confront the onset of ciguatera fish poisoning in Europe. Mar Drugs 2010; 8:1838-907. [PMID: 20631873 PMCID: PMC2901828 DOI: 10.3390/md8061838] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 05/18/2010] [Accepted: 06/10/2010] [Indexed: 11/29/2022] Open
Abstract
Ciguatera fish poisoning (CFP) occurs mainly when humans ingest finfish contaminated with ciguatoxins (CTXs). The complexity and variability of such toxins have made it difficult to develop reliable methods to routinely monitor CFP with specificity and sensitivity. This review aims to describe the methodologies available for CTX detection, including those based on the toxicological, biochemical, chemical, and pharmaceutical properties of CTXs. Selecting any of these methodological approaches for routine monitoring of ciguatera may be dependent upon the applicability of the method. However, identifying a reference validation method for CTXs is a critical and urgent issue, and is dependent upon the availability of certified CTX standards and the coordinated action of laboratories. Reports of CFP cases in European hospitals have been described in several countries, and are mostly due to travel to CFP endemic areas. Additionally, the recent detection of the CTX-producing tropical genus Gambierdiscus in the eastern Atlantic Ocean of the northern hemisphere and in the Mediterranean Sea, as well as the confirmation of CFP in the Canary Islands and possibly in Madeira, constitute other reasons to study the onset of CFP in Europe [1]. The question of the possible contribution of climate change to the distribution of toxin-producing microalgae and ciguateric fish is raised. The impact of ciguatera onset on European Union (EU) policies will be discussed with respect to EU regulations on marine toxins in seafood. Critical analysis and availability of methodologies for CTX determination is required for a rapid response to suspected CFP cases and to conduct sound CFP risk analysis.
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Affiliation(s)
- Amandine Caillaud
- IRTA, Ctra. Poble Nou, Km 5,5. 43540 Sant Carles de la Ràpita, Spain; E-Mails: (A.C.); (P.I.)
| | - Pablo de la Iglesia
- IRTA, Ctra. Poble Nou, Km 5,5. 43540 Sant Carles de la Ràpita, Spain; E-Mails: (A.C.); (P.I.)
| | - H. Taiana Darius
- Laboratoire des micro-algues toxiques, Institut Louis Malardé, BP30, 98713 Papeete Tahiti, French Polynesia; E-Mails: (H.T.D.); (M.C.)
| | - Serge Pauillac
- Institut Pasteur, 25-28 rue du docteur Roux, 75 015 Paris, France; E-Mail: (S.P.)
| | - Katerina Aligizaki
- Department of Botany, School of Biology, Faculty of Sciences, Aristotle University, 54 124 Thessaloniki, Greece; E-Mail: (K.A.)
| | - Santiago Fraga
- Instituto Español de Oceanografía, Subida a Radio Faro, 50, 36390 Vigo, Spain; E-Mail: (S.F.)
| | - Mireille Chinain
- Laboratoire des micro-algues toxiques, Institut Louis Malardé, BP30, 98713 Papeete Tahiti, French Polynesia; E-Mails: (H.T.D.); (M.C.)
| | - Jorge Diogène
- IRTA, Ctra. Poble Nou, Km 5,5. 43540 Sant Carles de la Ràpita, Spain; E-Mails: (A.C.); (P.I.)
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50
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Furuta H, Hasegawa Y, Hase M, Mori Y. Total Synthesis of Gambierol by Using Oxiranyl Anions. Chemistry 2010; 16:7586-95. [DOI: 10.1002/chem.201000497] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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