1
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Sasaki M, Iwasaki K, Arai K. Synthesis and Structural Implication of the JKLMN-Ring Fragment of Caribbean Ciguatoxin C-CTX-1. J Org Chem 2021; 86:4580-4597. [PMID: 33667088 DOI: 10.1021/acs.joc.0c03031] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Synthesis of the JKLMN-ring fragment of Caribbean ciguatoxin C-CTX-1, the causative toxin of ciguatera fish poisoning in the Caribbean Sea and the Northeast Atlantic areas, is described in detail. Key to the synthesis are a [2,3]-sigmatropic rearrangement to construct a seven-membered α-hydroxy exo-enol ether, stereoselective construction of an angular tetrasubstituted stereogenic center on the seven-membered M-ring by a hydrogen atom transfer-based reductive olefin coupling, Suzuki-Miyaura coupling of the KLMN-ring enol phosphate with a highly congested M-ring, and silica gel-mediated epoxide ring opening to form the J-ring. Comparison of the nuclear magnetic resonance spectroscopic data for the synthesized fragment with those for the natural product provided support for the formerly assigned structure of the N-ring in the right-hand terminal of C-CTX-1.
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Affiliation(s)
- Makoto Sasaki
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Japan
| | - Kotaro Iwasaki
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Japan
| | - Keisuke Arai
- Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Japan
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2
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Bartolo ND, Read JA, Valentín EM, Woerpel KA. Reactions of Allylmagnesium Reagents with Carbonyl Compounds and Compounds with C═N Double Bonds: Their Diastereoselectivities Generally Cannot Be Analyzed Using the Felkin-Anh and Chelation-Control Models. Chem Rev 2020; 120:1513-1619. [PMID: 31904936 PMCID: PMC7018623 DOI: 10.1021/acs.chemrev.9b00414] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
This review describes the additions of allylmagnesium reagents to carbonyl compounds and to imines, focusing on the differences in reactivity between allylmagnesium halides and other Grignard reagents. In many cases, allylmagnesium reagents either react with low stereoselectivity when other Grignard reagents react with high selectivity, or allylmagnesium reagents react with the opposite stereoselectivity. This review collects hundreds of examples, discusses the origins of stereoselectivities or the lack of stereoselectivity, and evaluates why selectivity may not occur and when it will likely occur.
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Affiliation(s)
- Nicole D. Bartolo
- Department of Chemistry, New York University, 100
Washington Square East, New York, NY 10003, USA
| | - Jacquelyne A. Read
- Department of Chemistry, New York University, 100
Washington Square East, New York, NY 10003, USA
- Department of Chemistry, University of Utah, 315 South 1400
East, Salt Lake City, UT 84112, USA
| | - Elizabeth M. Valentín
- Department of Chemistry, New York University, 100
Washington Square East, New York, NY 10003, USA
- Department of Chemistry, Susquehanna University, 514
University Avenue, Selinsgrove, PA 17870, USA
| | - K. A. Woerpel
- Department of Chemistry, New York University, 100
Washington Square East, New York, NY 10003, USA
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3
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Tsumuraya T, Hirama M. Rationally Designed Synthetic Haptens to Generate Anti-Ciguatoxin Monoclonal Antibodies, and Development of a Practical Sandwich ELISA to Detect Ciguatoxins. Toxins (Basel) 2019; 11:E533. [PMID: 31540301 PMCID: PMC6784113 DOI: 10.3390/toxins11090533] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/02/2019] [Accepted: 09/06/2019] [Indexed: 12/02/2022] Open
Abstract
"Ciguatera" fish poisoning (CFP) is one of the well-known food poisoning caused by the ingestion of fish that have accumulated trace amounts of ciguatoxins (CTXs). CFP affects more than 50,000 individuals annually. The difficulty in preventing CFP comes from the lack of reliable methods for analysis of CTXs in contaminated fish, together with the normal appearance, taste, and smell of CTX-contaminated fish. Thus, a sensitive, accurate, routine, and portable analytical method to detect CTXs is urgently required. Monoclonal antibodies (mAbs) specific against either wing of major CTX congeners (CTX1B, 54-deoxyCTX1B, CTX3C, and 51-hydroxyCTX3C) were generated by immunizing mice with rationally designed synthetic haptens-KLH conjugates instead of the CTXs. Haptenic groups with a surface area greater than 400 Å2 are required to produce mAbs that can strongly bind to CTXs. Furthermore, a highly sensitive fluorescence-based sandwich enzyme-linked immunosorbent assay (ELISA) was developed. This protocol can detect and quantify four major CTX congeners (CTX1B, 54-deoxyCTX1B, CTX3C, and 51-hydroxyCTX3C) with a limit of detection (LOD) of less than 1 pg/mL. The LOD determined for this sandwich ELISA is sufficient to detect CTX1B-contaminated fish at the FDA guidance level of 0.01 ppb.
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Affiliation(s)
- Takeshi Tsumuraya
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-2, Gakuen-cho, Naka-ku, Sakai, Osaka 599-8570, Japan.
| | - Masahiro Hirama
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-2, Gakuen-cho, Naka-ku, Sakai, Osaka 599-8570, Japan.
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4
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Tsumuraya T, Sato T, Hirama M, Fujii I. Highly Sensitive and Practical Fluorescent Sandwich ELISA for Ciguatoxins. Anal Chem 2018; 90:7318-7324. [PMID: 29770692 DOI: 10.1021/acs.analchem.8b00519] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ciguatera fish poisoning (CFP) caused by the consumption of fish that have accumulated ciguatoxins (CTXs) affects more than 50000 people annually. The spread of CFP causes enormous damage to public health, fishery resources, and the economies of tropical and subtropical endemic regions. The difficulty in avoiding CFP arises from the lack of sensitive and reliable analytical methods for the detection and quantification of CTXs in contaminated fish, along with the normal appearance, smell, and taste of fish contaminated with the causative toxins. Thus, an accurate, sensitive, routine, and portable detection method for CTXs is urgently required. We have successfully developed a highly sensitive fluorescent sandwich ELISA, which can detect, differentiate, and quantify four major CTX congeners (CTX1B, CTX3C, 51-hydroxyCTX3C, and 54-deoxyCTX1B) with a detection limit of less than 1 pg/mL. The ELISA protocol, using one microtiter plate coated with two mAbs (10C9 and 3G8), and ALP-linked 8H4, can detect any of the four CTX congeners in a single operation. CTX1B spiked into fish at the FDA guidance level of 0.01 ppb CTX1B equivalent toxicity in fish from Pacific regions was also proven to be reliably detected by this ELISA. Furthermore, the efficiency of extraction/purification procedures and the matrix effect of contaminants in fish were evaluated in detail, since pretreatment and matrix effects are critical for ELISA analysis.
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Affiliation(s)
- Takeshi Tsumuraya
- Department of Biological Science, Graduate School of Science , Osaka Prefecture University , Osaka 599-8570 , Japan
| | - Takeshi Sato
- Cell Science Inc. , Aoba-ku, Sendai , Miyagi 989-3212 , Japan
| | - Masahiro Hirama
- Department of Biological Science, Graduate School of Science , Osaka Prefecture University , Osaka 599-8570 , Japan
| | - Ikuo Fujii
- Department of Biological Science, Graduate School of Science , Osaka Prefecture University , Osaka 599-8570 , Japan
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5
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Onoue H, Marubayashi R, Ishikawa E, Konoki K, Torikai K, Ebine M, Murata M, Oishi T. Syntheses and Biological Activities of the LMNO, ent-LMNO, and NOPQR(S) Ring Systems of Maitotoxin. J Org Chem 2017; 82:9595-9618. [PMID: 28840731 DOI: 10.1021/acs.joc.7b01658] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Structure-activity relationship studies of maitotoxin (MTX), a marine natural product produced by an epiphytic dinoflagellate, were conducted using chemically synthesized model compounds corresponding to the partial structures of MTX. Both enantiomers of the LMNO ring system were synthesized via aldol reaction of the LM ring aldehyde and the NO ring ketone. These fragments were derived from a common cis-fused pyranopyran intermediate prepared through a sequence involving Nozaki-Hiyama-Kishi reaction, intramolecular oxa-Michael addition, and Pummerer rearrangement. The NOPQR(S) ring system, in which the original seven-membered S ring was substituted with a six-membered ring, was also synthesized through the coupling of the QR(S) ring alkyne and the NO ring aldehyde and the construction of the P ring via 1,4-reduction, dehydration, and hydroboration. The inhibitory activities of the synthetic specimens against MTX-induced Ca2+ influx were evaluated. The LMNO ring system and its enantiomer induced 36 and 18% inhibition, respectively, at 300 μM, whereas the NOPQR(S) ring system elicited no inhibitory activity.
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Affiliation(s)
- Hisaaki Onoue
- Department of Chemistry, Faculty and Graduate School of Science, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Riho Marubayashi
- Department of Chemistry, Faculty and Graduate School of Science, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Erina Ishikawa
- Department of Chemistry, Faculty and Graduate School of Science, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Keiichi Konoki
- Graduate School of Agricultural Science, Tohoku University , 1-1 Tsutsumidori Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan
| | - Kohei Torikai
- Department of Chemistry, Faculty and Graduate School of Science, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Makoto Ebine
- Department of Chemistry, Faculty and Graduate School of Science, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University , 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Tohru Oishi
- Department of Chemistry, Faculty and Graduate School of Science, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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6
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Read JA, Yang Y, Woerpel KA. Additions of Organomagnesium Halides to α-Alkoxy Ketones: Revision of the Chelation-Control Model. Org Lett 2017; 19:3346-3349. [DOI: 10.1021/acs.orglett.7b01161] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jacquelyne A. Read
- Department of Chemistry, New York University, New York, New York 10003, United States
| | - Yingying Yang
- Department of Chemistry, New York University, New York, New York 10003, United States
| | - K. A. Woerpel
- Department of Chemistry, New York University, New York, New York 10003, United States
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7
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Read JA, Woerpel KA. Allylmagnesium Halides Do Not React Chemoselectively Because Reaction Rates Approach the Diffusion Limit. J Org Chem 2017; 82:2300-2305. [DOI: 10.1021/acs.joc.7b00053] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jacquelyne A. Read
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - K. A. Woerpel
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
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9
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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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10
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Sakai T, Matsushita S, Arakawa S, Mori K, Tanimoto M, Tokumasu A, Yoshida T, Mori Y. Total Synthesis of Gymnocin-A. J Am Chem Soc 2015; 137:14513-6. [PMID: 26521846 DOI: 10.1021/jacs.5b10082] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A convergent total synthesis of cytotoxic marine natural polycyclic ether, gymnocin-A (1), is described. The synthesis features three iterations of an oxiranyl anion strategy, involving base-mediated cycloetherification, ring expansion, and reductive etherification, for the construction of the FGH fragment and for its coupling with the ABC and KLMN fragments.
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Affiliation(s)
- Takeo Sakai
- Faculty of Pharmacy, Meijo University , Yagotoyama 150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Shingo Matsushita
- Faculty of Pharmacy, Meijo University , Yagotoyama 150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Shogo Arakawa
- Faculty of Pharmacy, Meijo University , Yagotoyama 150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Koichi Mori
- Faculty of Pharmacy, Meijo University , Yagotoyama 150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Miki Tanimoto
- Faculty of Pharmacy, Meijo University , Yagotoyama 150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Akihiro Tokumasu
- Faculty of Pharmacy, Meijo University , Yagotoyama 150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Tatsuji Yoshida
- Faculty of Pharmacy, Meijo University , Yagotoyama 150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Yuji Mori
- Faculty of Pharmacy, Meijo University , Yagotoyama 150, Tempaku-ku, Nagoya 468-8503, Japan
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11
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Otte DAL, Woerpel KA. Evidence that Additions of Grignard Reagents to Aliphatic Aldehydes Do Not Involve Single-Electron-Transfer Processes. Org Lett 2015. [DOI: 10.1021/acs.orglett.5b01893] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Douglas A. L. Otte
- Department
of Chemistry, New York University, New York, New York 10003, United States
| | - K. A. Woerpel
- Department
of Chemistry, New York University, New York, New York 10003, United States
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12
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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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13
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14
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Sakai T, Asano H, Furukawa K, Oshima R, Mori Y. Synthesis of the KLMN Fragment of Gymnocin-A Using Oxiranyl Anion Convergent Methodology. Org Lett 2014; 16:2268-71. [DOI: 10.1021/ol500788c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Takeo Sakai
- Faculty
of Pharmacy, Meijo University, Yagotoyama
150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Haruka Asano
- Faculty
of Pharmacy, Meijo University, Yagotoyama
150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Kyoko Furukawa
- Faculty
of Pharmacy, Meijo University, Yagotoyama
150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Rie Oshima
- Faculty
of Pharmacy, Meijo University, Yagotoyama
150, Tempaku-ku, Nagoya 468-8503, Japan
| | - Yuji Mori
- Faculty
of Pharmacy, Meijo University, Yagotoyama
150, Tempaku-ku, Nagoya 468-8503, Japan
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15
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Kadota I, Shiroma K, Asakura H, Tanaka T, Takamura H. Improved Synthesis of the A-E Ring Segment of Ciguatoxin CTX3C. HETEROCYCLES 2014. [DOI: 10.3987/com-13-s(s)106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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16
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Herndon JW. The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2011. Coord Chem Rev 2013. [DOI: 10.1016/j.ccr.2013.05.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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17
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Boussonnière A, Bénéteau R, Lebreton J, Dénès F. Aluminum Acetals in Organic Synthesis. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300624] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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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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19
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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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20
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Tsumuraya T, Takeuchi K, Yamashita S, Fujii I, Hirama M. Development of a monoclonal antibody against the left wing of ciguatoxin CTX1B: Thiol strategy and detection using a sandwich ELISA. Toxicon 2012; 60:348-57. [DOI: 10.1016/j.toxicon.2012.04.347] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2011] [Revised: 02/20/2012] [Accepted: 04/18/2012] [Indexed: 11/30/2022]
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21
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Urabe D, Yamaguchi H, Someya A, Inoue M. Intermolecular Radical Reaction of O,Se-Acetals Generated via Seleno-Pummerer Rearrangement. Org Lett 2012; 14:3842-5. [DOI: 10.1021/ol301482f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daisuke Urabe
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hiroki Yamaguchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ayumi Someya
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masayuki Inoue
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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22
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23
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Ryan JH, Hyland C, Meyer AG, Smith JA, Yin J. Seven-Membered Rings. PROGRESS IN HETEROCYCLIC CHEMISTRY 2012. [DOI: 10.1016/b978-0-08-096807-0.00016-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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24
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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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25
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26
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Takamura H, Nishiuma N, Abe T, Kadota I. Convergent Synthesis of the HIJKLM Ring System of Ciguatoxin CTX3C. Org Lett 2011; 13:4704-7. [DOI: 10.1021/ol2019136] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hiroyoshi Takamura
- Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Naoki Nishiuma
- Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Takashi Abe
- Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Isao Kadota
- Division of Chemistry and Biochemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
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27
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Yamaoka K, Inoue M, Hirama M. A study on mechanisms of toxic actions of ciguatoxins: existence of functional relationship between CTX3C and charged residues of voltage sensors in Nav1.4 sodium channel. Forensic Toxicol 2011. [DOI: 10.1007/s11419-011-0113-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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