1
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Nishikawa K, Ono Y, Mori S, Takayama K, Ihara M, Matsuda K, Morimoto Y. Divergent Nine-Step Syntheses of Perhydrohistrionicotoxin Analogs and Their Inhibition Activity Toward Chicken α4β2-Neuronal Nicotinic Acetylcholine Receptors. J Org Chem 2024; 89:4128-4133. [PMID: 38407917 DOI: 10.1021/acs.joc.3c02988] [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: 02/27/2024]
Abstract
Histrionicotoxin (HTX) alkaloids, which are isolated from Colombian poison dart frogs, are analgesic neurotoxins that modulate nicotinic acetylcholine receptors (nAChRs) as antagonists. Perhydrohistrionicotoxin (pHTX) is the potent synthetic analogue of HTX and possesses a 1-azaspiro[5.5]undecane skeleton common to the HTX family. Here, we show for the first time the divergent nine-step synthesis of pHTX and its three stereoisomers from the known aldehyde through a one-step construction of the 1-azaspiro[5.5]undecane framework from a linear amino ynone substrate. Surprisingly, some pHTX diastereomers exhibited antagonistic activities on the chicken α4β2-neuronal nAChRs that were more potent than pHTX.
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Affiliation(s)
- Keisuke Nishikawa
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, Osaka 558-8585, Japan
| | - Yosuke Ono
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, Osaka 558-8585, Japan
| | - Sumito Mori
- Department of Applied Biological Chemistry, Faculty of Agriculture, Kindai University, Nara 631-8505, Japan
| | - Koichi Takayama
- Department of Applied Biological Chemistry, Faculty of Agriculture, Kindai University, Nara 631-8505, Japan
| | - Makoto Ihara
- Department of Applied Biological Chemistry, Faculty of Agriculture, Kindai University, Nara 631-8505, Japan
| | - Kazuhiko Matsuda
- Department of Applied Biological Chemistry, Faculty of Agriculture, Kindai University, Nara 631-8505, Japan
| | - Yoshiki Morimoto
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, Osaka 558-8585, Japan
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2
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Yoshimura A, Hanzawa R, Fuwa H. Stereoselective Tandem Synthesis of Pyrrolidine Derivatives under Gold Catalysis: An Asymmetric Synthesis of (-)-Lepadiformine A. Org Lett 2022; 24:6237-6241. [PMID: 35849685 DOI: 10.1021/acs.orglett.2c02007] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A Au-catalyzed tandem alkyne hydroamination/iminium ion formation/allylation reaction was developed for expedient access to pyrrolidine derivatives bearing a tetrasubstituted carbon stereocenter. The tandem reaction was successfully applied to a 12-step asymmetric synthesis of (-)-lepadiformine A, a marine cytotoxic tricyclic alkaloid.
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Affiliation(s)
- Atsushi Yoshimura
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Ryohei Hanzawa
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Haruhiko Fuwa
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
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3
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Nishikibe K, Nishikawa K, Kumagai M, Doe M, Morimoto Y. Asymmetric Total Syntheses, Stereostructures, and Cytotoxicities of Marine Bromotriterpenoids Aplysiol B (Laurenmariannol) and Saiyacenol A. Chem Asian J 2021; 17:e202101137. [PMID: 34704367 PMCID: PMC9299038 DOI: 10.1002/asia.202101137] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/26/2021] [Indexed: 11/29/2022]
Abstract
There are marine cytotoxic bromotriterpenoids, named the thyrsiferol family that are structurally characterized by some tetrahydropyran (THP) and tetrahydrofuran (THF) rings. The thyrsiferol family belongs to natural products that are often difficult to determine their stereostructures even by the current, highly advanced spectroscopic methods, especially in acyclic systems including stereogenic tetrasubstituted carbon centers. In such cases, it is effective to predict and synthesize the possible stereostructures. Herein, to elucidate ambiguous stereostructures and unassigned absolute configurations of aplysiol B, laurenmariannol, and saiyacenol A, members of the thyrsiferol family, we carried out their asymmetric chemical syntheses featuring 6‐exo and 5‐exo oxacyclizations of epoxy alcohol precursors and 6‐endo bromoetherification of a bishomoallylic alcohol. In this paper, we report total assignments of their stereostructures through their asymmetric chemical syntheses and also their preliminary cytotoxic activities against some tumor cells. These results could not have been achieved without depending on asymmetric total synthesis.
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Affiliation(s)
- Kento Nishikibe
- Department of Chemistry, Graduate School of Science, Osaka City University Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Keisuke Nishikawa
- Department of Chemistry, Graduate School of Science, Osaka City University Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Momochika Kumagai
- Department of Chemistry, Graduate School of Science, Osaka City University Sumiyoshi-ku, Osaka, 558-8585, Japan.,Faculty of Fisheries, Kagoshima University Shimoarata, Kagoshima, 8900056, Japan
| | - Matsumi Doe
- Department of Chemistry, Graduate School of Science, Osaka City University Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Yoshiki Morimoto
- Department of Chemistry, Graduate School of Science, Osaka City University Sumiyoshi-ku, Osaka, 558-8585, Japan
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4
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Mandal S, Chaudhari RD, Biswas G. Advances in mercury(II)-salt-mediated cyclization reactions of unsaturated bonds. Beilstein J Org Chem 2021; 17:2348-2376. [PMID: 34621398 PMCID: PMC8450975 DOI: 10.3762/bjoc.17.153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 08/27/2021] [Indexed: 11/23/2022] Open
Abstract
The synthesis of complex cyclic compounds is extremely challenging for organic chemists. Many transition-metal-salt-mediated cyclizations are reported in literature. Hg(II) salts have been successfully employed in cyclizations to form complex heterocyclic and carbocyclic structures that are impossible to synthesize with other transition metal salts. In this review, we have summarized cyclization reactions that are performed with Hg(II) salts. These salts are also successfully applied in stoichiometric or catalytic amounts to form complex cyclic structures and natural products.
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Affiliation(s)
- Sumana Mandal
- Department of Chemistry, Cooch Behar Panchanan Barma University, Panchanan Nagar, Vivekananda Street, Cooch Behar - 736101, West Bengal, India
| | - Raju D Chaudhari
- Department of Chemistry, Cooch Behar Panchanan Barma University, Panchanan Nagar, Vivekananda Street, Cooch Behar - 736101, West Bengal, India
| | - Goutam Biswas
- Department of Chemistry, Cooch Behar Panchanan Barma University, Panchanan Nagar, Vivekananda Street, Cooch Behar - 736101, West Bengal, India
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5
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Matsumura K, Nishikawa K, Yoshida H, Niwa T, Fushii Y, Doe M, Morimoto Y. One-Step Synthesis of the 1-Azaspiro[5.5]undecane Skeleton Characteristic of Histrionicotoxin Alkaloids from Linear Substrates via Hg(OTf) 2 -Catalyzed Cycloisomerization. Chem Asian J 2021; 16:1882-1886. [PMID: 33973732 DOI: 10.1002/asia.202100383] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/08/2021] [Indexed: 11/10/2022]
Abstract
Histrionicotoxin (HTX) alkaloids isolated from the poison arrow frogs possess a unique structure characterized by a 1-azaspiro[5.5]undecane skeleton common to the HTX family. The unique molecular architecture of HTXs and the interest as potential target drugs have prompted synthetic chemists to promote the total synthesis so far. However, all of the synthetic strategies to access the 1-azaspiro[5.5]undecane framework of HTXs take a multistep approach from linear starting materials due to stepwise construction of either six-membered carbo- or azacycle. Herein, we report the direct one-step construction of the 1-azaspiro[5.5]undecane skeleton from linear amino ynone substrates bearing an N-methoxycarbonyl group utilizing our mercuric triflate (Hg(OTf)2 )-catalyzed cycloisomerization reaction. The utility of this novel methodology was demonstrated by the total and formal syntheses of HTX-235A and HTX-283A, respectively, from the azaspirocycle.
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Affiliation(s)
- Kunihiro Matsumura
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Keisuke Nishikawa
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Hiroaki Yoshida
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Toshiki Niwa
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Yuichiro Fushii
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Matsumi Doe
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Yoshiki Morimoto
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, 558-8585, Japan
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6
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Nishikawa K, Kumagai M, Matsumura K, Nishikibe K, Morimoto Y. Natural Product Synthesis Strategy Based on the Concept of Directly Constructing the Ring Skeletons from Linear Substrates. J SYN ORG CHEM JPN 2021. [DOI: 10.5059/yukigoseikyokaishi.79.197] [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)
- Keisuke Nishikawa
- Department of Chemistry, Graduate School of Science, Osaka City University
| | | | | | | | - Yoshiki Morimoto
- Department of Chemistry, Graduate School of Science, Osaka City University
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7
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Nishikawa K, Noguchi T, Kikuchi S, Maruyama T, Araki Y, Yotsu-Yamashita M, Morimoto Y. Tetrodotoxin Framework Construction from Linear Substrates Utilizing a Hg(OTf)2-Catalyzed Cycloisomerization Reaction: Synthesis of the Unnatural Analogue 11-nor-6,7,8-Trideoxytetrodotoxin. Org Lett 2021; 23:1703-1708. [DOI: 10.1021/acs.orglett.1c00125] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Keisuke Nishikawa
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka, Osaka 558-8585, Japan
| | - Takayuki Noguchi
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka, Osaka 558-8585, Japan
| | - Seiho Kikuchi
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka, Osaka 558-8585, Japan
| | - Takahiro Maruyama
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka, Osaka 558-8585, Japan
| | - Yusuke Araki
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka, Osaka 558-8585, Japan
| | - Mari Yotsu-Yamashita
- Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi 980-8572, Japan
| | - Yoshiki Morimoto
- Department of Chemistry, Graduate School of Science, Osaka City University, Osaka, Osaka 558-8585, Japan
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8
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Grundke C, Vierengel N, Opatz T. ‐Aminonitriles: From Sustainable Preparation to Applications in Natural Product Synthesis. CHEM REC 2020; 20:989-1016. [DOI: 10.1002/tcr.202000066] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/02/2020] [Accepted: 07/02/2020] [Indexed: 12/21/2022]
Affiliation(s)
- Caroline Grundke
- Department of Chemistry Johannes Gutenberg University Duesbergweg 10–14 55128 Mainz Germany
| | - Nina Vierengel
- Department of Chemistry Johannes Gutenberg University Duesbergweg 10–14 55128 Mainz Germany
| | - Till Opatz
- Department of Chemistry Johannes Gutenberg University Duesbergweg 10–14 55128 Mainz Germany
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9
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Wu JL, Chiou WH. Diastereocontrolled Formal Syntheses of (±)-Lepadiformines A, B, and C and the Divergent Synthesis of 2- epi-Lepadiformine C through Unexpected Double Consecutive Epimerizations. J Org Chem 2020; 85:9051-9063. [PMID: 32580551 DOI: 10.1021/acs.joc.0c00964] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We describe here the diastereocontrolled formal racemic syntheses of tricyclic marine alkaloids, lepadiformines A, B, and C as well as their C2 epimers, featuring divergent and stereoselective syntheses of the N-acetyl-8a-cyanodecahydroquinoline frameworks and the base-mediated intramolecular cyclization to establish the spiral quaternary center of the tricyclic framework from sterically well-defined α-aminonitrile 2. The approach allows us to accomplish the tricyclic core structure efficiently from readily available starting materials through simple operations. An unexpected pair of consecutive epimerizations at two contiguous stereocenters is observed on the basis of single-crystal X-ray analyses of the intermediates and derivatives. The findings have been successfully applied to the total synthesis of 2-epi-lepadiformine C. The epimerization mechanism has been elucidated through a series of deuterium-labelling-controlled experiments.
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Affiliation(s)
- Jui-Lin Wu
- Department of Chemistry, National Chung-Hsing University, Taichung 402, Taiwan, R.O.C
| | - Wen-Hua Chiou
- Department of Chemistry, National Chung-Hsing University, Taichung 402, Taiwan, R.O.C
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10
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Shimomura M, Sato M, Azuma H, Sakata J, Tokuyama H. Total Synthesis of (-)-Lepadiformine A via Radical Translocation-Cyclization Reaction. Org Lett 2020; 22:3313-3317. [PMID: 32182082 DOI: 10.1021/acs.orglett.0c00474] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Total synthesis of (-)-lepadiformine A featuring construction of the 1-azaspiro[4.5]decane skeleton by a highly diastereoselective radical translocation-cyclization reaction of a γ-lactam derivative bearing a chiral butenolide moiety is described. The enantioselective construction of butenolide is conducted via Krische's catalytic asymmetric allylation protocol. After the radical translocation-cyclization reaction, a hydroxymethyl group at the C-13 position was stereoselectively introduced by a one-pot partial reduction-allylation protocol of the unprotected lactam derivative. Finally, the total synthesis is completed by formation of a C ring.
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Affiliation(s)
- Masashi Shimomura
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Manabu Sato
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Hiroki Azuma
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Juri Sakata
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Hidetoshi Tokuyama
- Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
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11
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Lin HC, Xie PP, Dai ZY, Zhang SQ, Wang PS, Chen YG, Wang TC, Hong X, Gong LZ. Nucleophile-Dependent Z/E- and Regioselectivity in the Palladium-Catalyzed Asymmetric Allylic C–H Alkylation of 1,4-Dienes. J Am Chem Soc 2019; 141:5824-5834. [DOI: 10.1021/jacs.8b13582] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hua-Chen Lin
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Pei-Pei Xie
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Zhen-Yao Dai
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Shuo-Qing Zhang
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Pu-Sheng Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Yu-Gen Chen
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Tian-Ci Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Xin Hong
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Liu-Zhu Gong
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
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12
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Abstract
Covering: January to December 2017This review covers the literature published in 2017 for marine natural products (MNPs), with 740 citations (723 for the period January to December 2017) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, mangroves and other intertidal plants and microorganisms. The emphasis is on new compounds (1490 in 477 papers for 2017), together with the relevant biological activities, source organisms and country of origin. Reviews, biosynthetic studies, first syntheses, and syntheses that led to the revision of structures or stereochemistries, have been included. Geographic distributions of MNPs at a phylogenetic level are reported.
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Affiliation(s)
- Anthony R Carroll
- School of Environment and Science, Griffith University, Gold Coast, Australia. and Griffith Institute for Drug Discovery, Griffith University, Brisbane, Australia
| | - Brent R Copp
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Rohan A Davis
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, Australia
| | - Robert A Keyzers
- Centre for Biodiscovery, School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington, New Zealand
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13
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Gong Y, Cao ZY, Shi YB, Zhou F, Zhou Y, Zhou J. A highly efficient Hg(OTf)2-mediated Sakurai–Hosomi allylation of N-tert-butyloxycarbonylamino sulfones, aldehydes, fluoroalkyl ketones and α,β-unsaturated enones using allyltrimethylsilane. Org Chem Front 2019. [DOI: 10.1039/c9qo01049a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The cheap and easily available Hg(OTf)2 can efficiently mediate the Sakurai–Hosomi reaction of N-Boc amino sulfones, aldehydes, α-fluoroalkyl ketones and α,β-unsaturated enones using allyltrimethylsilane with the catalyst loading down to 0.5–5.0 mol%.
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Affiliation(s)
- Yi Gong
- College of Pharmacy
- Guiyang University of Chinese Medicine
- Guiyang 550025
- P. R. China
| | - Zhong-Yan Cao
- Shanghai Key Laboratory of Green Chemistry and Chemical Process
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development
- East China Normal University
- Shanghai 200062
- P. R. China
| | - Ying-Bo Shi
- College of Chemistry and Material Sciences
- Sichuan Normal University
- Chengdu
- P. R. China
| | - Feng Zhou
- Shanghai Key Laboratory of Green Chemistry and Chemical Process
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development
- East China Normal University
- Shanghai 200062
- P. R. China
| | - Ying Zhou
- College of Pharmacy
- Guiyang University of Chinese Medicine
- Guiyang 550025
- P. R. China
| | - Jian Zhou
- Shanghai Key Laboratory of Green Chemistry and Chemical Process
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development
- East China Normal University
- Shanghai 200062
- P. R. China
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14
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Matsumura K, Nishikawa K, Yoshida H, Doe M, Morimoto Y. Formal total synthesis of histrionicotoxin alkaloids via Hg(OTf)2-catalyzed cycloisomerization and SmI2-induced ring expansion. RSC Adv 2018; 8:11296-11303. [PMID: 35542821 PMCID: PMC9079123 DOI: 10.1039/c8ra02011f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 03/12/2018] [Indexed: 12/30/2022] Open
Abstract
The efficient formal total synthesis of histrionicotoxin alkaloids was achieved via Hg(OTf)2-catalyzed cycloisomerization and SmI2-induced ring expansion.
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Affiliation(s)
- Kunihiro Matsumura
- Department of Chemistry
- Graduate School of Science
- Osaka City University Sumiyoshi-ku
- Osaka 558-8585
- Japan
| | - Keisuke Nishikawa
- Department of Chemistry
- Graduate School of Science
- Osaka City University Sumiyoshi-ku
- Osaka 558-8585
- Japan
| | - Hiroaki Yoshida
- Department of Chemistry
- Graduate School of Science
- Osaka City University Sumiyoshi-ku
- Osaka 558-8585
- Japan
| | - Matsumi Doe
- Department of Chemistry
- Graduate School of Science
- Osaka City University Sumiyoshi-ku
- Osaka 558-8585
- Japan
| | - Yoshiki Morimoto
- Department of Chemistry
- Graduate School of Science
- Osaka City University Sumiyoshi-ku
- Osaka 558-8585
- Japan
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