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Liu X, Du Y, Xie W, Li X, Xu J, Chen Y, Mei Z, Yang G. Scalemic diacetylenic spiroacetal enol ethers from the flowers of Tanacetum tatsienense. PHYTOCHEMISTRY 2023; 209:113619. [PMID: 36828098 DOI: 10.1016/j.phytochem.2023.113619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 02/20/2023] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
Six scalemic mixtures of previously undescribed diacetylenic spiroacetal enol ethers (DSEEs) and six scalemic mixtures of known DSEEs were isolated from the flowers of Tanacetum tatsienense. Except for E-epidendranthemenol, Z-O-acetyl-epi dendranthemenol, and Z-O-isovaleryl-epidendranthemenol, the remaining scalemic mixtures of DSEEs were resolved by chiral HPLC, and their structures were determined through an analysis of HR-ESI-MS and NMR data. The absolute configurations of seven pairs of enantiomers and one pair of epimers were determined by comparing the experimental and calculated electronic circular dichroism (ECD) spectra. In addition, the inhibitory effects of all of the DSEEs on nitric oxide (NO) production were evaluated in LPS-stimulated RAW264.7 cells. The results showed that (+)-tatsienenol B had a weak inhibitory effect on NO production. The IC50 value of the compound was 19.78 ± 0.78 μM. This study is the first to report that DSEEs are isolable from plants as scalemic mixtures. Moreover, this study is the first to determine the absolute configurations of DSEEs by chiral resolution and ECD calculations.
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Affiliation(s)
- Xinqiao Liu
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan, 430074, PR China
| | - Yan Du
- College of Chemistry and Material Sciences, South-Central Minzu University, Wuhan, 430074, PR China
| | - Wenli Xie
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan, 430074, PR China
| | - Xueni Li
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan, 430074, PR China
| | - Jing Xu
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan, 430074, PR China
| | - Yu Chen
- College of Chemistry and Material Sciences, South-Central Minzu University, Wuhan, 430074, PR China
| | - Zhinan Mei
- College of Plant Science & Technology, Huazhong Agricultural University, Wuhan, 430072, PR China.
| | - Guangzhong Yang
- School of Pharmaceutical Sciences, South-Central Minzu University, Wuhan, 430074, PR China; Ethnopharmacology Level 3 Laboratory, National Administration of Traditional Chinese Medicine, Wuhan, 430072, PR China.
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2
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Petko D, Koh S, Tam W. Transition Metal-Catalyzed Reactions of Alkynyl Halides. Curr Org Synth 2020; 16:546-582. [PMID: 31984930 DOI: 10.2174/1570179416666190329200616] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 02/08/2019] [Accepted: 02/20/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Transition metal-catalyzed reactions of alkynyl halides are a versatile means of synthesizing a wide array of products. Their use is of particular interest in cycloaddition reactions and in constructing new carbon-carbon and carbon-heteroatom bonds. Transition metal-catalyzed reactions of alkynyl halides have successfully been used in [4+2], [2+2], [2+2+2] and [3+2] cycloaddition reactions. Many carbon-carbon coupling reactions take advantage of metal-catalyzed reactions of alkynyl halides, including Cadiot-Chodkiewicz, Suzuki-Miyaura, Stille, Kumada-Corriu and Inverse Sonogashira reactions. All the methods of constructing carbon-nitrogen, carbon-oxygen, carbon-phosphorus, carbon-sulfur, carbon-silicon, carbon-selenium and carbon-tellurium bonds employed alkynyl halides. OBJECTIVE The purpose of this review is to highlight and summarize research conducted in transition metalcatalyzed reactions of alkynyl halides in recent years. The focus will be placed on cycloaddition and coupling reactions, and their scope and applicability to the synthesis of biologically important and industrially relevant compounds will be discussed. CONCLUSION It can be seen from the review that the work done on this topic has employed the use of many different transition metal catalysts to perform various cycloadditions, cyclizations, and couplings using alkynyl halides. The reactions involving alkynyl halides were efficient in generating both carbon-carbon and carbonheteroatom bonds. Proposed mechanisms were included to support the understanding of such reactions. Many of these reactions face retention of the halide moiety, allowing additional functionalization of the products, with some new products being inaccessible using their standard alkyne counterparts.
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Affiliation(s)
- Dina Petko
- Guelph-Waterloo Center for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Samuel Koh
- Guelph-Waterloo Center for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - William Tam
- Guelph-Waterloo Center for Graduate Work in Chemistry and Biochemistry, Department of Chemistry, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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3
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Palanivel A, Mubeen S, Warner T, Ahmed N, Clive DLJ. Formation of Enol Ethers by Radical Decarboxylation of α-Alkoxy β-Phenylthio Acids. J Org Chem 2019; 84:12542-12552. [PMID: 31462047 DOI: 10.1021/acs.joc.9b02042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Enol ethers are formed by radical decarboxylation of α-alkoxy β-phenylthio acids via the corresponding Barton esters. The phenylthio acids were usually made by the known regioselective reaction of α,β-epoxy acids with PhSH in the presence of InCl3, followed by O-alkylation of the resulting alcohol. In one case, thiol addition to an α,β-unsaturated ethoxymethyl ester was used.
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Affiliation(s)
- Ashokkumar Palanivel
- Chemistry Department , University of Alberta , Edmonton , Alberta T6G 2G2 , Canada
| | - Sidra Mubeen
- Chemistry Department , University of Alberta , Edmonton , Alberta T6G 2G2 , Canada
| | - Thomas Warner
- Chemistry Department , University of Alberta , Edmonton , Alberta T6G 2G2 , Canada
| | - Nayeem Ahmed
- Chemistry Department , University of Alberta , Edmonton , Alberta T6G 2G2 , Canada
| | - Derrick L J Clive
- Chemistry Department , University of Alberta , Edmonton , Alberta T6G 2G2 , Canada
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4
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B-ring-homo-tonghaosu, isolated from Chrysanthemum morifolium capitulum, acts as a peroxisome proliferator-activated receptor-γ agonist. J Nat Med 2019; 73:497-503. [DOI: 10.1007/s11418-019-01290-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 02/07/2019] [Indexed: 01/11/2023]
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5
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Abstract
Three kinds of transformations based on benzo-fused donor- and acceptor-enynals/enynones, including reactions with alkenes, alkynes, and H2O, were discussed.
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Affiliation(s)
- Lianfen Chen
- Key Laboratory of Functional Molecular Engineering of Guangdong Province
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou
- P. R. China
| | - Zhili Liu
- Key Laboratory of Functional Molecular Engineering of Guangdong Province
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou
- P. R. China
| | - Shifa Zhu
- Key Laboratory of Functional Molecular Engineering of Guangdong Province
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou
- P. R. China
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6
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Mukai C. Creation of Novel Cyclization Methods Using sp-Hybridized Carbon Units and Syntheses of Bioactive Compounds. Chem Pharm Bull (Tokyo) 2017; 65:511-523. [PMID: 28566644 DOI: 10.1248/cpb.c17-00088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Some recent results on the development of new and reliable procedures for the construction of diverse ring systems based on the chemistry of sp-hybridized species, especially allene functionality, are described. This review includes: (i) synthesis of the multi-cyclic skeletons by combination of the π-component of allene with suitable other π-components such as alkyne, alkene, or additional allene under Rh-catalyzed conditions; (ii) synthesis of heterocycles as well as carbocycles by reaction of the sp-hybridized center of allene with some nucleophiles in an endo-mode manner; and (iii) total syntheses of natural products and related compounds from the sp-hybridized starting materials.
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Affiliation(s)
- Chisato Mukai
- Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University
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8
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Urabe D, Todoroki H, Inoue M. Asymmetric Total Synthesis of (−)-4-Hydroxyzinowol, a Highly Oxygenated Dihydro-β-Agarofuran. J SYN ORG CHEM JPN 2015. [DOI: 10.5059/yukigoseikyokaishi.73.1081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | | | - Masayuki Inoue
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
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9
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Zeng YT, Jiang JM, Lao HY, Guo JW, Lun YN, Yang M. Antitumor and apoptotic activities of the chemical constituents from the ethyl acetate extract of Artemisia indica. Mol Med Rep 2014; 11:2234-40. [PMID: 25434991 DOI: 10.3892/mmr.2014.3012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 07/04/2014] [Indexed: 11/06/2022] Open
Abstract
Cancer is one of the most eminent diseases of modern times and numerous natural products derived from medicinal plants have been identified as potential sources of antitumor drugs. A successful anticancer drug must target or inhibit tumor cells whilst causing minimal damage to healthy cells. The present study aimed to investigate the antitumor efficacy of ethyl acetate extract, and other isolated compounds from Artemisia indica, on MCF‑7, BHY, Miapaca‑2, Colo‑205 and A‑549 cell lines. The apoptotic activity of the compounds was studied using flow cytometry. The different cancer cell lines were treated with the ethyl acetate extract and varying concentrations of compounds (denoted a‑g) isolated from the A. indica. The cytotoxicity was evaluated by MTT assay and the apoptotic properties of the compounds and the extract were assessed using flow cytometry. In MCF‑7 cells, the effect on mitochondrial membrane potential loss (ΛΨm) induced by compounds b and d was also studied. Bioassay‑guided fractionation of the ethyl acetate extract from the shoot and root parts of A. indica led to the identification of the compounds a‑g as: 5‑hydroxy‑3,7,4'‑trimethoxyflavone; ludartin; maackiain; lupeol; cis‑matricaria ester; trans‑matricaria ester; and 6‑methoxy‑7,8‑methylenedioxy coumarin, respectively. All the compounds exhibited mild to potent inhibition of cell proliferation in all the cell lines, with the half maximal inhibitory concentration values ranging from 25.18‑88.12 µM. Ludartin and lupeol were observed to have the most potent inhibitory effects. Based on the initially identified antiproliferative effects, these two compounds were evaluated for their effects on cell cycle phase distribution, DNA damage and their effects on mitochondrial membrane potential loss (ΛΨm). The two compounds induced DNA damage and mitochondrial membrane potential loss in MCF‑7 cells. The results of the current study suggest that lupeol and ludartin, isolated from A. indica, produce anticancer effects by inducing DNA damage and a reduction of mitochondrial membrane potential, and may be used as potent anticancer agents, subsequent to further study.
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Affiliation(s)
- Ying-Tong Zeng
- Department of Pharmacy, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
| | - Jian-Min Jiang
- Lab of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat‑Sen University, Guangzhou, Guangdong 510006, P.R. China
| | - Hai-Yan Lao
- Department of Pharmacy, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
| | - Jie-Wen Guo
- Department of Pharmacy, Guangzhou Hospital of Traditional Chinese Medicine, Guangzhou, Guangdong 510130, P.R. China
| | - Yu-Ning Lun
- Department of Pharmacy, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
| | - Min Yang
- Department of Pharmacy, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510080, P.R. China
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10
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Todoroki H, Iwatsu M, Urabe D, Inoue M. Total Synthesis of (−)-4-Hydroxyzinowol. J Org Chem 2014; 79:8835-49. [DOI: 10.1021/jo501666x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hidenori Todoroki
- Graduate School of Pharmaceutical
Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masafumi Iwatsu
- Graduate School of Pharmaceutical
Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Daisuke Urabe
- 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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11
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Yin B, Zhang X, Liu J, Li X, Jiang H. Practical access to spiroacetal enol ethers via nucleophilic dearomatization of 2-furylmethylenepalladium halides generated by Pd-catalyzed coupling of furfural tosylhydrazones with aryl halides. Chem Commun (Camb) 2014; 50:8113-6. [DOI: 10.1039/c4cc01725k] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Trant JF, Hudlicky T. Ring-opening of hindered cyclic epoxides with potassium carboxylates in the presence of conjugate acids. CAN J CHEM 2013. [DOI: 10.1139/cjc-2013-0386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
During attempts to ring-open a highly hindered epoxide, traditional methods were found to be ineffective. An alternative strategy for opening epoxides was implemented that employed a potassium carboxylate in the presence of its conjugate acid in a solvent mixture containing polar and potassium-sequestering components. A systematic analysis of the components of the reaction mixture indicated that the addition of the conjugate acid was the most important feature for providing good conversion. This reaction appears to be general for most classes of carboxylic acids including cinnamic, aromatic, and highly hindered carboxylic acids (30%–79% yield) and only fails with weak carboxylate nucleophiles. Three highly substituted and hindered cyclohexene oxide derivatives were examined for reactivity and the reaction conditions appear to tolerate a variety of functional groups to provide the ring-opened species. This pH-moderate system proved useful for hindered cyclic epoxides when all other techniques failed and should prove general to a wide spectrum of epoxide and carboxylic acid partners in those cases where the use of a strong Lewis or protic acid catalyst, or a strong basic nucleophile, is inappropriate.
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Affiliation(s)
- John F. Trant
- Department of Chemistry and Centre for Biotechnology, Brock University, 500 Glenridge Avenue, St. Catharines, ON L2S 3A1, Canada
| | - Tomas Hudlicky
- Department of Chemistry and Centre for Biotechnology, Brock University, 500 Glenridge Avenue, St. Catharines, ON L2S 3A1, Canada
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13
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Kumar P, Dwivedi N. Proline catalyzed α-aminoxylation reaction in the synthesis of biologically active compounds. Acc Chem Res 2013; 46:289-99. [PMID: 23148510 DOI: 10.1021/ar300135u] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The search for new and efficient ways to synthesize optically pure compounds is an active area of research in organic synthesis. Asymmetric catalysis provides a practical, cost-effective, and efficient method to create a variety of complex natural products containing multiple stereocenters. In recent years, chemists have become more interested in using small organic molecules to catalyze organic reactions. As a result, organocatalysis has emerged both as a promising strategy and as an alternative to catalysis with expensive proteins or toxic metals. One of the most successful and widely studied secondary amine-based organocatalysts is proline. This small molecule can catalyze numerous reactions such as the aldol, Mannich, Michael addition, Robinson annulation, Diels-Alder, α-functionalization, α-amination, and α-aminoxylation reactions. Catalytic and enantioselective α-oxygenation of carbonyl compounds is an important reaction to access a variety of useful building blocks for bioactive molecules. Proline catalyzed α-aminoxylation using nitrosobenzene as oxygen source, followed by in situ reduction, gives enantiomerically pure 1,2-diol. This molecule can then undergo a variety of organic reactions. In addition, proline organocatalysis provides access to an assortment of biologically active natural products including mevinoline (a cholesterol lowering drug), tetrahydrolipstatin (an antiobesity drug), R(+)-α-lipoic acid, and bovidic acid. In this Account, we present an iterative organocatalytic approach to synthesize both syn- and anti-1,3-polyols, both enantio- and stereoselectively. This method is primarily based on proline-catalyzed sequential α-aminoxylation and Horner-Wadsworth-Emmons (HWE) olefination of aldehyde to give a γ-hydroxy ester. In addition, we briefly illustrate the broad application of our recently developed strategy for 1,3-polyols, which serve as valuable, enantiopure building blocks for polyketides and other structurally diverse and complex natural products. Other research groups have also applied similar strategies to prepare such bioactive molecules as littoralisone, brasoside and (+)-cytotrienin A. Among the various synthetic approaches reported for 1,3-polyols, our organocatalytic iterative approach appears to be very promising and robust. This method combines the merit of organocatalytic reaction with an easy access to both enantiomerically pure forms of proline, mild reaction conditions, and tolerance to both air and moisture. In this Account, we present the latest applications of organocatalysis and how organic chemists can use this new tool for the total synthesis of complex natural products.
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Affiliation(s)
- Pradeep Kumar
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
| | - Namrata Dwivedi
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
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14
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Das S, Induvadana B, Ramana C. Metal-mediated alkynediol cycloisomerization: first and second generation formal total syntheses of didemniserinolipid B. Tetrahedron 2013. [DOI: 10.1016/j.tet.2012.12.045] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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15
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16
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Wu B, Feast GC, Thompson AL, Robertson J. Synthesis of Stereoisomers of Artemisia and Chrysanthemum Bis(acetylenic) Enol Ether Spiroacetals. J Org Chem 2012; 77:10623-30. [DOI: 10.1021/jo301810d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Boshen Wu
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA,
U.K
| | - George C. Feast
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA,
U.K
| | - Amber L. Thompson
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA,
U.K
| | - Jeremy Robertson
- Department of Chemistry,
Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA,
U.K
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17
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Wu XF, Neumann H, Beller M. Synthesis of Heterocycles via Palladium-Catalyzed Carbonylations. Chem Rev 2012; 113:1-35. [DOI: 10.1021/cr300100s] [Citation(s) in RCA: 961] [Impact Index Per Article: 80.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Xiao-Feng Wu
- Department of Chemistry, Zhejiang
Sci-Tech University, Xiasha Campus, Hangzhou, Zhejiang Province, P.
R. China 310018
- Leibniz-Institut
für
Katalyse e.V. an der Universität Rostock, Albert-Einstein-Strasse
29a, 18059 Rostock, Germany
| | - Helfried Neumann
- Leibniz-Institut
für
Katalyse e.V. an der Universität Rostock, Albert-Einstein-Strasse
29a, 18059 Rostock, Germany
| | - Matthias Beller
- Leibniz-Institut
für
Katalyse e.V. an der Universität Rostock, Albert-Einstein-Strasse
29a, 18059 Rostock, Germany
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18
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Trant JF, Belding L, Dudding T, Hudlicky T. Application of D- chiro-Inositol as a Chiral Template for the DielsAlderReaction. Helv Chim Acta 2012. [DOI: 10.1002/hlca.201200432] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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A flexible organocatalytic enantioselective synthesis of heptadeca-1-ene-4,6-diyne-3S,8R,9S,10S-tetrol and its congeners. Tetrahedron 2012. [DOI: 10.1016/j.tet.2011.10.058] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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20
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The absolute configuration determination of naturally occurring diacetylenic spiroacetal enol ethers from Artemisia lactiflora. Tetrahedron 2011. [DOI: 10.1016/j.tet.2011.03.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Narute SB, Kiran NC, Ramana CV. A [Pd]-mediated ω-alkynone cycloisomerization approach for the central tetrahydropyran unit and the synthesis of C(31)–C(48) fragment of aflastatin A. Org Biomol Chem 2011; 9:5469-75. [DOI: 10.1039/c1ob05251a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Zhang Y, Wu Y. An enantioselective total synthesis of natural antibiotic marasin. Org Biomol Chem 2010; 8:4744-52. [PMID: 20725668 DOI: 10.1039/c0ob00151a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Synthetic studies directed toward the allenediyne antibiotic marasin are presented. Different approaches to the installation of the optically active chiral allenediyne motif were explored en route to the synthesis of the natural product. The stereoselectivity for the construction of the chiral allenediyne motif was dependent on not only the reaction employed but also the substrate structure.
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Affiliation(s)
- Yan Zhang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China
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Nielsen M, Jacobsen CB, Paixão MW, Holub N, Jørgensen KA. Asymmetric Organocatalytic Formal Alkynylation and Alkenylation of α,β-Unsaturated Aldehydes. J Am Chem Soc 2009; 131:10581-6. [DOI: 10.1021/ja903920j] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Martin Nielsen
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | | | - Márcio W. Paixão
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Nicole Holub
- 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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Robertson J, Naud S. Synthesis of Spiroacetal Enol Ethers by Oxidative Activation of Furan Derivatives. Org Lett 2008; 10:5445-8. [DOI: 10.1021/ol802138t] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jeremy Robertson
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, U.K
| | - Sébastien Naud
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, U.K
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25
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Bahnck KB, Rychnovsky SD. Formal synthesis of (-)-kendomycin featuring a Prins-cyclization to construct the macrocycle. J Am Chem Soc 2008; 130:13177-81. [PMID: 18767844 PMCID: PMC2697922 DOI: 10.1021/ja805187p] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The kendomycin skeleton was prepared by a highly convergent strategy in which the benzofuran fragment and the acyclic iodide fragment were prepared by standard methods and joined using a Suzuki coupling. The distinctive reaction in our approach was an intramolecular Prins cyclization that assembles the macrocyclic ring in good yield. Modeling studies demonstrate that the acyclic chain is predisposed for macrocycle formation. Ultimately, the product was correlated with one of Lee's advanced intermediates for a formal total synthesis of kendomycin.
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Affiliation(s)
- Kevin B. Bahnck
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California, 92697-2025
| | - Scott D. Rychnovsky
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California, 92697-2025
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27
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Synthetic studies of spiroketal enol ethers: an unexpected oxidation by Martin’s sulfurane. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.01.167] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
Over the past fifty years, hundreds of polyyne compounds have been isolated from nature. These often unstable molecules are found in sources as common as garden vegetables and as obscure as bacterial cultures. Naturally occurring polyynes feature a wide range of structural diversity and display an equally broad array of biological properties. Early synthetic efforts relied primarily on Cu-catalyzed, oxidative acetylenic homo- and heterocoupling reactions to assemble the polyyne framework. The past 25 years, however, have witnessed a renaissance in the field of polyyne natural product synthesis: transition-metal-catalyzed alkynylation reactions and asymmetric transformations have combined to substantially expand access to natural polyynes. This Review recounts these synthetic achievements and also highlights both the natural source(s) and biological relevance for many of these compounds.
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