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Ma F, Li Y, Akkarasereenon K, Qiu H, Cheung YT, Guo Z, Tong R. Aza-Achmatowicz rearrangement coupled with intermolecular aza-Friedel-Crafts enables total syntheses of uleine and aspidosperma alkaloids. Chem Sci 2024; 15:5730-5737. [PMID: 38638226 PMCID: PMC11023026 DOI: 10.1039/d4sc00601a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 03/11/2024] [Indexed: 04/20/2024] Open
Abstract
Aspidosperma and uleine alkaloids belong to the large family of monoterpene indole alkaloids with diverse biological activities and thus have attracted extensive synthetic interest. Reported is the development of a new synthetic strategy that allows direct C3-C2' linkage of indoles with functionalized 2-hydroxypiperidines to construct the core common to all aspidoserma and uleine alkaloids. Such indole-piperidine linkage is enabled by coupling aza-Achmatowicz rearrangement (AAR) with indoles via an intermolecular aza-Friedel-Crafts (iAFC) reaction. This AAR-iAFC reaction proceeds under mild acidic conditions with wide tolerance of functional groups (33 examples). The synthetic application of the AAR-iAFC method was demonstrated with collective total syntheses of 3 uleine-type and 6 aspidosperma alkaloids: (+)-3-epi-N-nor-dasycarpidone, (+)-3-epi-dasycarpidone, (+)-3-epi-uleine, 1,2-didehydropseudoaspidospermidine, 1,2-dehydroaspidospermidine, vincadifformine, winchinine B, aspidospermidine, and N-acetylaspidospermidine. We expect that this AAR-iAFC strategy is applicable to other monoterpene indole alkaloids with the C3-C2' linkage of indoles and piperidines.
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Affiliation(s)
- Foqing Ma
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay Kowloon Hong Kong China +86 23581594 +86 23587357
| | - Yunlong Li
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay Kowloon Hong Kong China +86 23581594 +86 23587357
| | - Kornkamon Akkarasereenon
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay Kowloon Hong Kong China +86 23581594 +86 23587357
| | - Huiying Qiu
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay Kowloon Hong Kong China +86 23581594 +86 23587357
| | - Yuen Tsz Cheung
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay Kowloon Hong Kong China +86 23581594 +86 23587357
| | - Zhihong Guo
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay Kowloon Hong Kong China +86 23581594 +86 23587357
| | - Rongbiao Tong
- Department of Chemistry, The Hong Kong University of Science and Technology, Clearwater Bay Kowloon Hong Kong China +86 23581594 +86 23587357
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2
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Xie J, Pahl A, Krzyzanowski A, Krupp A, Liu J, Koska S, Schölermann B, Zhang R, Bonowski J, Sievers S, Strohmann C, Ziegler S, Grigalunas M, Waldmann H. Synthetic Matching of Complex Monoterpene Indole Alkaloid Chemical Space. Angew Chem Int Ed Engl 2023; 62:e202310222. [PMID: 37818743 DOI: 10.1002/anie.202310222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 10/02/2023] [Accepted: 10/06/2023] [Indexed: 10/13/2023]
Abstract
Monoterpene indole alkaloids (MIAs) are endowed with high structural and spatial complexity and characterized by diverse biological activities. Given this complexity-activity combination in MIAs, rapid and efficient access to chemical matter related to and with complexity similar to these alkaloids would be highly desirable, since such compound classes might display novel bioactivity. We describe the design and synthesis of a pseudo-natural product (pseudo-NP) collection obtained by the unprecedented combination of MIA fragments through complexity-generating transformations, resulting in arrangements not currently accessible by biosynthetic pathways. Cheminformatic analyses revealed that both the pseudo-NPs and the MIAs reside in a unique and common area of chemical space with high spatial complexity-density that is only sparsely populated by other natural products and drugs. Investigation of bioactivity guided by morphological profiling identified pseudo-NPs that inhibit DNA synthesis and modulate tubulin. These results demonstrate that the pseudo-NP collection occupies similar biologically relevant chemical space that Nature has endowed MIAs with.
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Affiliation(s)
- Jianing Xie
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Axel Pahl
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
- Compound Management and Screening Center (COMAS), Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Adrian Krzyzanowski
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
- Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Straße 6, 44227, Dortmund, Germany
| | - Anna Krupp
- Faculty of Chemistry, Inorganic Chemistry, TU Dortmund University, Otto-Hahn-Straße 6, 44227, Dortmund, Germany
| | - Jie Liu
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Sandra Koska
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Beate Schölermann
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Ruirui Zhang
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Jana Bonowski
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Sonja Sievers
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
- Compound Management and Screening Center (COMAS), Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Carsten Strohmann
- Faculty of Chemistry, Inorganic Chemistry, TU Dortmund University, Otto-Hahn-Straße 6, 44227, Dortmund, Germany
| | - Slava Ziegler
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Michael Grigalunas
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Herbert Waldmann
- Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
- Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Straße 6, 44227, Dortmund, Germany
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3
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Tang Y, Huang M, Jiang L, Zhang X, Zheng S, Yang Y, Chen XY. Visible-Light-Irradiated Multicomponent Reactions of Aliphatic Amines, Propiolate Acid Esters, and CF 3 SO 2 Na for Accessing β-CF 3 Enamines. Chemistry 2023; 29:e202302249. [PMID: 37572319 DOI: 10.1002/chem.202302249] [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: 07/14/2023] [Revised: 08/10/2023] [Accepted: 08/10/2023] [Indexed: 08/14/2023]
Abstract
A novel one-pot two-step multicomponent reaction has been achieved for the preparation of β-CF3 enamines by using different aliphatic amines, propiolates, and CF3 SO2 Na as starting material. In this protocol, various aliphatic amines including primary amines, cyclic or acyclic secondary amines were demonstrated to be good coupling partners, and different β-CF3 enamines were obtained in moderate to good yields. Among them, the primary aliphatic amines only gave pure (E)-β-CF3 enamines as products. The synthetic utility of the MCRs strategy was further demonstrated by mild conditions, gram-scale synthesis and natural sunlight-induced protocol. Preliminary mechanistic studies suggest that this trifluoromethylation of C(sp2 )-H involves radical process.
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Affiliation(s)
- Yisong Tang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, P. R. China
| | - Mingyang Huang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, P. R. China
| | - Liang Jiang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, P. R. China
| | - Xiaotong Zhang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, P. R. China
| | - Shaojun Zheng
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, P. R. China
| | - Yong Yang
- College of Mechanical Engineering, Suzhou University of Science and Technology, Suzhou, 320500, P. R. China
| | - Xiao Yun Chen
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, 212003, P. R. China
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4
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Cain D, Anderson NA, Cordes DB, Slawin AMZ, Watson AJB. Total Synthesis of (±)-Aspidospermidine, (±)-Aspidofractinine, (±)-Limaspermidine, and (±)-Vincadifformine via a Cascade and Common Intermediate Strategy. J Org Chem 2022; 87:15559-15563. [PMID: 36259765 PMCID: PMC9680024 DOI: 10.1021/acs.joc.2c02099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A concise strategy for the total synthesis of several Aspidosperma alkaloids is reported. A Suzuki-Miyaura cross-coupling provides access to a 2-vinyl indole that undergoes a Diels-Alder cascade reaction with butyn-2-one to deliver a pyrroloindoline intermediate. This undergoes cascade amidation, reduction, skeletal rearrangement, and intramolecular Michael addition to provide a common intermediate containing the full framework of the Aspidosperma alkaloids. The utility of this intermediate is shown in the synthesis of four different natural products.
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Affiliation(s)
- David
L. Cain
- EaStCHEM,
School of Chemistry, University of St Andrews, North Haugh, Fife, St AndrewsKY16 9ST, U.K.
| | - Niall A. Anderson
- GlaxoSmithKline, Medicines Research Centre, Gunnels Wood Road, StevenageSG1 2NY, U.K.
| | - David B. Cordes
- EaStCHEM,
School of Chemistry, University of St Andrews, North Haugh, Fife, St AndrewsKY16 9ST, U.K.
| | - Alexandra M. Z. Slawin
- EaStCHEM,
School of Chemistry, University of St Andrews, North Haugh, Fife, St AndrewsKY16 9ST, U.K.
| | - Allan J. B. Watson
- EaStCHEM,
School of Chemistry, University of St Andrews, North Haugh, Fife, St AndrewsKY16 9ST, U.K.,
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5
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Horst B, Verdoorn DS, Hennig S, van der Heijden G, Ruijter E. Enantioselective Total Synthesis of (-)-Limaspermidine and (-)-Kopsinine by a Nitroaryl Transfer Cascade Strategy. Angew Chem Int Ed Engl 2022; 61:e202210592. [PMID: 36004723 PMCID: PMC9826323 DOI: 10.1002/anie.202210592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Indexed: 01/11/2023]
Abstract
We report an intramolecular conjugate addition/Truce-Smiles/E1cb cascade of 2-nitrobenzenesulfonamide-functionalized cyclohexenones as a new entry to the core scaffold of monoterpene indole alkaloids. The method was applied to the asymmetric total synthesis of (-)-limaspermidine, (-)-kopsinilam, and (-)-kopsinine, as well as the framework of the kopsifoline alkaloids, thus highlighting its complementarity to existing approaches involving the use of indole-based starting materials or the interrupted Fischer indole synthesis. Furthermore, we show that the cascade tolerates various substituents on the nitroarene, opening the way to other natural products as well as non-natural analogues.
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Affiliation(s)
- Brendan Horst
- Department of Chemistry and Pharmaceutical SciencesAmsterdam Institute of Molecular and Life Sciences (AIMMS)De Boelelaan 11081081 HZAmsterdamThe Netherlands
| | - Daniël S. Verdoorn
- Department of Chemistry and Pharmaceutical SciencesAmsterdam Institute of Molecular and Life Sciences (AIMMS)De Boelelaan 11081081 HZAmsterdamThe Netherlands
| | - Sven Hennig
- Department of Chemistry and Pharmaceutical SciencesAmsterdam Institute of Molecular and Life Sciences (AIMMS)De Boelelaan 11081081 HZAmsterdamThe Netherlands
| | - Gydo van der Heijden
- Department of Chemistry and Pharmaceutical SciencesAmsterdam Institute of Molecular and Life Sciences (AIMMS)De Boelelaan 11081081 HZAmsterdamThe Netherlands
| | - Eelco Ruijter
- Department of Chemistry and Pharmaceutical SciencesAmsterdam Institute of Molecular and Life Sciences (AIMMS)De Boelelaan 11081081 HZAmsterdamThe Netherlands
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6
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Horst B, Verdoorn DS, Hennig S, van der Heijden G, Ruijter E. Enantioselective Total Synthesis of (–)‐Limaspermidine and (–)‐Kopsinine by a Nitroaryl Transfer Cascade Strategy. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202210592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Brendan Horst
- Vrije Universiteit Amsterdam Chemistry & Pharmaceutical Sciences NETHERLANDS
| | - Daniël S. Verdoorn
- Vrije Universiteit Amsterdam Chemistry & Pharmaceutical Sciences NETHERLANDS
| | - Sven Hennig
- Vrije Universiteit Amsterdam Chemistry & Pharmaceutical Sciences NETHERLANDS
| | | | - Eelco Ruijter
- Vrije Universiteit Amsterdam Chemistry & Pharmaceutical Sciences De Boelelaan 11081081 HZNetherlands 1081 HZ Amsterdam NETHERLANDS
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7
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Łowicki D, Przybylski P. Tandem construction of biological relevant aliphatic 5-membered N-heterocycles. Eur J Med Chem 2022; 235:114303. [PMID: 35344904 DOI: 10.1016/j.ejmech.2022.114303] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 12/20/2022]
Abstract
Nature often uses cascade reactions in a highly stereocontrolled manner for assembly structurally diverse nitrogen-containing heterocyclic scaffolds, i.e. secondary metabolites, important for medicinal chemistry and pharmacy. Five-membered nitrogen-containing heterocycles as standalone rings, as well as spiro and polycyclic systems are pharmacophores of drugs approved in various therapies, i.a. antibacterial or antiviral, antifungal, anticancer, antidiabetic, as they target many key enzymes. Furthermore, a large number of pyrrolidine derivatives are currently considered as drug candidates. Cascade transformations, also known as domino or tandem reactions, offer straightforward methods to build N-heterocyclic libraries of the great structural variety desired for drawing SAR conclusions. The tandem transformations are often atom economic and time-saving because they are performed as the one-pot, so no need for purification after each 'virtual' step and the limited necessity of protective groups are characteristic for these processes. Thus, the same results as in classical multistep synthesis can be achieved at markedly lower costs and shorter time, which is in line with modern green chemistry rules. Great advantage of cascade reactions is often reflected in their high regio- and stereoselectivities, enabling the preparing of the heterocyclic compound better fitted to the expected target in cells. This review reveals the biological relevance of N-heterocyclic scaffolds based on saturated 5-membered rings since we showed a number of examples of approved drugs together with the recent biologically attractive leading structures of drug candidates. Next, novel cascade synthetic procedures, taking into account the structure of the reactants and reaction mechanisms, enabling to obtain biological-relevant heterocyclic frameworks with good yields and relatively high stereoselectivity, were reviewed and compared. The review covers the advances of designing biological active N-heterocycles mainly from 2018 to 2021, whereas the synthetic part is focused on the last 7 years.
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Affiliation(s)
- Daniel Łowicki
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614, Poznan, Poland
| | - Piotr Przybylski
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614, Poznan, Poland.
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8
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Vrabec R, Maříková J, Ločárek M, Korábečný J, Hulcová D, Hošťálková A, Kuneš J, Chlebek J, Kučera T, Hrabinová M, Jun D, Soukup O, Andrisano V, Jenčo J, Šafratová M, Nováková L, Opletal L, Cahlíková L. Monoterpene indole alkaloids from Vinca minor L. (Apocynaceae): Identification of new structural scaffold for treatment of Alzheimer's disease. PHYTOCHEMISTRY 2022; 194:113017. [PMID: 34798410 DOI: 10.1016/j.phytochem.2021.113017] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/25/2021] [Accepted: 11/09/2021] [Indexed: 05/24/2023]
Abstract
One undescribed indole alkaloid together with twenty-two known compounds have been isolated from aerial parts of Vinca minor L. (Apocynaceae). The chemical structures of the isolated alkaloids were determined by a combination of MS, HRMS, 1D, and 2D NMR techniques, and by comparison with literature data. The NMR data of several alkaloids have been revised, corrected, and missing data have been supplemented. Alkaloids isolated in sufficient quantity were screened for their in vitro acetylcholinesterase (AChE; E.C. 3.1.1.7) and butyrylcholinesterase (BuChE; E.C. 3.1.1.8) inhibitory activity. Selected compounds were also evaluated for prolyl oligopeptidase (POP; E.C. 3.4.21.26), and glycogen synthase 3β-kinase (GSK-3β; E.C. 2.7.11.26) inhibition potential. Significant hBuChE inhibition activity has been shown by (-)-2-ethyl-3[2-(3-ethylpiperidinyl)-ethyl]-1H-indole with an IC50 value of 0.65 ± 0.16 μM. This compound was further studied by enzyme kinetics, along with in silico techniques, to reveal the mode of inhibition. This compound is also predicted to cross the blood-brain barrier (BBB) through passive diffusion.
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Affiliation(s)
- Rudolf Vrabec
- ADINACO Research Group, Department of Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic; Department of Pharmacognosy, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Jana Maříková
- Department of Bioorganic and Organic Chemistry, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Miroslav Ločárek
- ADINACO Research Group, Department of Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Jan Korábečný
- Department of Toxicology and Military Pharmacy, Trebesska 1575, 500 05, Hradec Kralove, Czech Republic; Biomedical Research Centre, University Hospital Hradec Kralove, Sokolska 581, 500 05, Hradec Kralove, Czech Republic
| | - Daniela Hulcová
- ADINACO Research Group, Department of Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic; Department of Pharmacognosy, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Anna Hošťálková
- ADINACO Research Group, Department of Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Jiří Kuneš
- Department of Bioorganic and Organic Chemistry, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Jakub Chlebek
- ADINACO Research Group, Department of Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Tomáš Kučera
- Department of Toxicology and Military Pharmacy, Trebesska 1575, 500 05, Hradec Kralove, Czech Republic
| | - Martina Hrabinová
- Department of Toxicology and Military Pharmacy, Trebesska 1575, 500 05, Hradec Kralove, Czech Republic
| | - Daniel Jun
- Department of Toxicology and Military Pharmacy, Trebesska 1575, 500 05, Hradec Kralove, Czech Republic
| | - Ondřej Soukup
- Department of Toxicology and Military Pharmacy, Trebesska 1575, 500 05, Hradec Kralove, Czech Republic; Biomedical Research Centre, University Hospital Hradec Kralove, Sokolska 581, 500 05, Hradec Kralove, Czech Republic
| | - Vincenza Andrisano
- Department for Life Quality Studies, University of Bologna, 47921, Rimini, Italy
| | - Jaroslav Jenčo
- ADINACO Research Group, Department of Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Marcela Šafratová
- Department of Pharmacognosy, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Lucie Nováková
- Department of Analytical Chemistry, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Lubomír Opletal
- ADINACO Research Group, Department of Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
| | - Lucie Cahlíková
- ADINACO Research Group, Department of Pharmaceutical Botany, Faculty of Pharmacy, Charles University, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic.
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9
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Schempp TT, Krische MJ. Total Synthesis of the Acetyl CoA Carboxylase Inhibitor Soraphen A: Asymmetric Tsuji Reduction Enables Successive Olefin Metathesis. J Am Chem Soc 2022; 144:1016-1022. [PMID: 35005976 PMCID: PMC8852841 DOI: 10.1021/jacs.1c12063] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The total synthesis of soraphen A, a myxobacterial metabolite and inhibitor of acetyl CoA carboxylase, was completed in 11 steps (longest linear sequence), less than half the steps previously required. Seven metal-catalyzed processes were deployed to unlock step-economy (comprising five asymmetric processes and four C-C bond formations). The present route does not utilize chiral auxiliaries, and four of five C-C bond formations exploit non-premetalated partners. To maximize convergency, an asymmetric Tsuji reduction was developed using a Pd-AntPhos catalyst that allows a metathesis-inactive allylic carbonate to serve as a masked terminal olefin, thereby enabling successive olefin metathesis events.
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Affiliation(s)
- Tabitha T. Schempp
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Michael J. Krische
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
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10
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Zhang F, Ren BT, Zhou Y, Liu Y, Feng X. Enantioselective Construction of cis-Hydroindole Scaffolds via Asymmetric Inverse-Electron-Demand Diels–Alder Reaction: Application to the Formal Total Synthesis of (+)-Minovincine. Chem Sci 2022; 13:5562-5567. [PMID: 35694337 PMCID: PMC9116300 DOI: 10.1039/d2sc01458k] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 04/14/2022] [Indexed: 11/21/2022] Open
Abstract
cis-Hydroindole scaffolds widely exist in a large number of natural products, pharmaceuticals, and organocatalysts. Therefore, the development of efficient and enantioselective methods for the construction of cis-hydroindoles is of great interest and importance. Herein, a novel approach for the enantioselective synthesis of cis-hydroindole scaffolds has been realized through a chiral N,N′-dioxide/Mg(OTf)2 complex catalyzed asymmetric inverse-electron-demand Diels–Alder (IEDDA) reaction of 2-pyrones and cyclic enamines. A series of substituted cis-hydroindole derivatives bearing multiple contiguous stereocenters and functional groups were obtained in good to excellent yields and enantioselectivities (up to 99% yield, and 95% ee) under mild reaction conditions. Moreover, the enantioselective formal total synthesis of (+)-minovincine was concisely furnished with high efficiency and stereoselectivity to demonstrate the synthetic potential of this method. An enantioselective IEDDA reaction between 2-pyrone and cyclic enamine was realized to construct cis-hydroindoles in high yield and ee, providing a concise route for formal total synthesis of (+)-minovincine.![]()
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Affiliation(s)
- Fangqing Zhang
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School Shenzhen Guangdong 518055 China
- Shenzhen Bay Laboratory Shenzhen 518055 China
| | | | - Yuqiao Zhou
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University Chengdu 610064 China
| | - Yangbin Liu
- Shenzhen Bay Laboratory Shenzhen 518055 China
| | - Xiaoming Feng
- Shenzhen Bay Laboratory Shenzhen 518055 China
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University Chengdu 610064 China
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11
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Heravi MM, Amiri Z, Kafshdarzadeh K, Zadsirjan V. Synthesis of indole derivatives as prevalent moieties present in selected alkaloids. RSC Adv 2021; 11:33540-33612. [PMID: 35497516 PMCID: PMC9042329 DOI: 10.1039/d1ra05972f] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 09/10/2021] [Indexed: 02/02/2023] Open
Abstract
Indoles are a significant heterocyclic system in natural products and drugs. They are important types of molecules and natural products and play a main role in cell biology. The application of indole derivatives as biologically active compounds for the treatment of cancer cells, microbes, and different types of disorders in the human body has attracted increasing attention in recent years. Indoles, both natural and synthetic, show various biologically vital properties. Owing to the importance of this significant ring system, the investigation of novel methods of synthesis have attracted the attention of the chemical community. In this review, we aim to highlight the construction of indoles as a moiety in selected alkaloids.
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Affiliation(s)
- Majid M Heravi
- Department of Chemistry, School of Physics and Chemistry, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Zahra Amiri
- Department of Chemistry, School of Physics and Chemistry, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Kosar Kafshdarzadeh
- Department of Chemistry, School of Physics and Chemistry, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Vahideh Zadsirjan
- Department of Chemistry, School of Physics and Chemistry, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
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12
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Wang N, Wu Z, Wang J, Ullah N, Lu Y. Recent applications of asymmetric organocatalytic annulation reactions in natural product synthesis. Chem Soc Rev 2021; 50:9766-9793. [PMID: 34286704 DOI: 10.1039/d0cs01124j] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The past two decades have witnessed remarkable growth of asymmetric organocatalysis, which is now a firmly established synthetic tool, serving as a powerful platform for the production of chiral molecules. Ring structures are ubiquitous in organic compounds, and, in the context of natural product synthesis, strategic construction of ring motifs is often crucial, fundamentally impacting the eventual fate of the whole synthetic plan. In this review, we provide a comprehensive and updated summary of asymmetric organocatalytic annulation reactions; in particular, the application of these annulation strategies in natural product synthesis will be highlighted.
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Affiliation(s)
- Nengzhong Wang
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore.
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13
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Abstract
Interrupted reactions reroute established processes to new and often unanticipated end points. Of particular interest are the cases in which a known reactive intermediate takes on a new reaction pathway, either because this pathway is lower in energy or because the conventional pathway is no longer available. Through analysis of documented cases, we aim to dissect the known interrupted reactions and trace their mechanistic origins. As new chemical processes are being discovered at a seemingly ever-increasing pace, it is likely that new interrupted reactions will continue to emerge. Our hope is that the cases considered in this Review will help identify new classes of these fascinating transformations.
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14
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Rani S, Dash SR, Bera A, Alam MN, Vanka K, Maity P. Phosphite mediated asymmetric N to C migration for the synthesis of chiral heterocycles from primary amines. Chem Sci 2021; 12:8996-9003. [PMID: 34276927 PMCID: PMC8261767 DOI: 10.1039/d1sc01217g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 05/27/2021] [Indexed: 11/21/2022] Open
Abstract
A phosphite mediated stereoretentive C-H alkylation of N-alkylpyridinium salts derived from chiral primary amines was achieved. The reaction proceeds through the activation of the N-alkylpyridinium salt substrate with a nucleophilic phosphite catalyst, followed by a base mediated [1,2] aza-Wittig rearrangement and subsequent catalyst dissociation for an overall N to C-2 alkyl migration. The scope and degree of stereoretention were studied, and both experimental and theoretical investigations were performed to support an unprecedented aza-Wittig rearrangement-rearomatization sequence. A catalytic enantioselective version starting with racemic starting material and chiral phosphite catalyst was also established following our understanding of the stereoretentive process. This method provides efficient access to tertiary and quaternary stereogenic centers in pyridine systems, which are prevalent in drugs, bioactive natural products, chiral ligands, and catalysts.
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Affiliation(s)
- Soniya Rani
- Organic Chemistry Division, CSIR-National Chemical Laboratory Pune-411008 India
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad-201002 India
| | - Soumya Ranjan Dash
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad-201002 India
- Physical and Material Chemistry Division, CSIR-National Chemical Laboratory Pune 411008 India
| | - Asish Bera
- Organic Chemistry Division, CSIR-National Chemical Laboratory Pune-411008 India
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad-201002 India
| | - Md Nirshad Alam
- Organic Chemistry Division, CSIR-National Chemical Laboratory Pune-411008 India
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad-201002 India
| | - Kumar Vanka
- Academy of Scientific and Innovative Research (AcSIR) Ghaziabad-201002 India
- Physical and Material Chemistry Division, CSIR-National Chemical Laboratory Pune 411008 India
| | - Pradip Maity
- Organic Chemistry Division, CSIR-National Chemical Laboratory Pune-411008 India
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15
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Nakagawa Y, Yamaguchi K, Hosokawa S. Iodide-Mediated [3 + 2]-Cycloaddition Reaction with N-Tosylaziridines and α,β-Unsaturated Ketones. J Org Chem 2021; 86:7787-7796. [PMID: 34032429 DOI: 10.1021/acs.joc.1c00532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The [3 + 2]-cycloaddition reaction between N-tosylaziridines and α,β-unsaturated ketones was promoted with lithium iodide. The reaction proceeded under mild conditions to provide N-tosylpyrrolidines. Quaternary carbon-possessing 3,3-disubstituted pyrrolidines including spiro compounds were afforded in high yields. A simple procedure with easy to handle reagents makes this reaction concise. The intramolecular version of this reaction was applied to synthesize tropane skeletons.
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Affiliation(s)
- Yuya Nakagawa
- Department of Applied Chemistry, Faculty of Advanced Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Keigo Yamaguchi
- Department of Applied Chemistry, Faculty of Advanced Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555, Japan
| | - Seijiro Hosokawa
- Department of Applied Chemistry, Faculty of Advanced Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555, Japan
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16
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Poulsen TB. Total Synthesis of Natural Products Containing Enamine or Enol Ether Derivatives. Acc Chem Res 2021; 54:1830-1842. [PMID: 33660974 DOI: 10.1021/acs.accounts.0c00851] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Enamine and enol ethers are nucleophilic functional groups that are well known to most chemists. When enamine or enol ethers are present in natural products, they are nearly exclusively found as derivatives having a direct connection to electron-withdrawing groups for stabilization, and the resulting larger entities, such as enamides or enol acylates, can be further extended or modified in the framework of natural products. The restricted conformational space that is associated with even simple enamine and enol ether derivatives can be a strong determinant of the overall molecular structure, and the more polarized derivatives can endow some natural products with electrophilic properties and thus facilitate covalent interactions with biological targets.In this Account, I describe our efforts (published since 2016) to prepare natural products from several different classes that all feature enamine or enol ether derivatives as key functionalities. Our choice of targets has been guided by a desire to illuminate unknown biological mechanisms associated with the compounds or, alternatively, to improve upon known biological activities that appear to be promising from a biomedical perspective. In the present text, however, the exclusive focus will be on the syntheses.First, I will discuss the basic properties of the functional groups and briefly present a small collection of illustrative and inspirational examples from the literature for their construction in different complex settings. Next, I will provide an overview of our work on the macrocyclic APD-CLD natural products, rakicidin A and BE-43547A1, involving the development of an efficient macrocyclization strategy and the development of methods to construct the hallmark APD group: a modified enamide. The synthesis of the meroterpenoid strongylophorine-26 is discussed next, where we developed an oxidative quinone methoxylation to build a vinylogous ester group in the final step of the synthesis and employed FeCl3-mediated cascade reactions for the rapid assembly of the overall scaffold to enable a short semisynthesis from isocupressic acid. An efficient core scaffold assembly was also in focus in our synthesis of the alkaloid streptazone A with the signature enaminone system being assembled through a rhodium-catalyzed Pauson-Khand reaction. Sequential, site-selective redox manipulations were developed to arrive at strepatzone A and additional members of the natural product family. Finally, I discuss our work to prepare analogs of complex polyether ionophores featuring functionalized tetronic acids as cation-binding groups. A method for the construction of a suitably protected chloromethylidene-modified tetronate is presented which enabled its installation in the full structure through a C-acylation reaction. This work exemplifies how components of abundant polyether ionophores can be recycled and used to access new structures which may possess enhanced biological activities.
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Affiliation(s)
- Thomas B. Poulsen
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
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17
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Wang N, Jiang X. Synthetic Approaches to Tricyclic Aminoketones in the Total Synthesis of Aspidosperma and Kopsia Alkaloids. CHEM REC 2020; 21:295-314. [PMID: 33289266 DOI: 10.1002/tcr.202000131] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 11/21/2020] [Accepted: 11/23/2020] [Indexed: 12/13/2022]
Abstract
Aspidosperma and kopsia alkaloids are significant functional molecules because of their potent biological activities. Their intricate structures present an intrinsic synthetic challenge and thus attract significant attention from synthetic organic academic community. Over the past decades, a series of elegant strategies has been developed, in particular, the Stork's original Fischer indolization of tricyclic aminoketones 1. Herein, we report a comprehensive review on various synthetic approaches access to tricyclic aminoketones 1 and provide a practical guidance to readers whose are interested in employing tricyclic aminoketones 1 as versatile building blocks in the realm of total synthesis of aspidosperma, kopsia and structurally related alkaloids.
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Affiliation(s)
- Nengzhong Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical Process, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, P. R. China
| | - Xuefeng Jiang
- Shanghai Key Laboratory of Green Chemistry and Chemical Process, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062, P. R. China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China
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18
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Wang S, Si R, Zhuang Q, Guo X, Ke T, Zhang X, Zhang F, Tu Y. Collective Total Synthesis of Aspidofractinine Alkaloids through the Development of a Bischler–Napieralski/Semipinacol Rearrangement Reaction. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202009238] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Shuang‐Hu Wang
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Rui‐Qi Si
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Qing‐Bo Zhuang
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Xiang Guo
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Tian Ke
- School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University Shanghai 200240 P. R. China
| | - Xiao‐Ming Zhang
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Fu‐Min Zhang
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Yong‐Qiang Tu
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
- School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University Shanghai 200240 P. R. China
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19
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Wang S, Si R, Zhuang Q, Guo X, Ke T, Zhang X, Zhang F, Tu Y. Collective Total Synthesis of Aspidofractinine Alkaloids through the Development of a Bischler–Napieralski/Semipinacol Rearrangement Reaction. Angew Chem Int Ed Engl 2020; 59:21954-21958. [DOI: 10.1002/anie.202009238] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Indexed: 01/01/2023]
Affiliation(s)
- Shuang‐Hu Wang
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Rui‐Qi Si
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Qing‐Bo Zhuang
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Xiang Guo
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Tian Ke
- School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University Shanghai 200240 P. R. China
| | - Xiao‐Ming Zhang
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Fu‐Min Zhang
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
| | - Yong‐Qiang Tu
- State Key Laboratory of Applied Organic Chemistry and Department of Chemistry Lanzhou University Lanzhou 730000 P. R. China
- School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University Shanghai 200240 P. R. China
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20
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Martin G, Angyal P, Egyed O, Varga S, Soós T. Total Syntheses of Dihydroindole Aspidosperma Alkaloids: Reductive Interrupted Fischer Indolization Followed by Redox Diversification. Org Lett 2020; 22:4675-4679. [PMID: 32497431 PMCID: PMC7467818 DOI: 10.1021/acs.orglett.0c01472] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Indexed: 01/22/2023]
Abstract
We report a novel reductive interrupted Fischer indolization process for the concise assembly of the 20-oxoaspidospermidine framework. This rapid complexity generating route paves the way toward various dihydroindole Aspidosperma alkaloids with different C-5 side chain redox patterns. The end-game redox modulations were accomplished by modified Wolff-Kishner reaction and photo-Wolff rearrangement, enabling the total synthesis of (-)-aspidospermidine, (-)-limaspermidine, and (+)-17-demethoxy-N-acetylcylindrocarine and the formal total synthesis of (-)-1-acetylaspidoalbidine.
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Affiliation(s)
- Gábor Martin
- Institute
of Organic Chemistry, Research Centre for
Natural Sciences, 2 Magyar tudósok krt., Budapest, H-1117, Hungary
| | - Péter Angyal
- Institute
of Organic Chemistry, Research Centre for
Natural Sciences, 2 Magyar tudósok krt., Budapest, H-1117, Hungary
| | - Orsolya Egyed
- Instrumentation
Center, Research Centre for Natural Sciences, 2 Magyar tudósok krt., Budapest, H-1117, Hungary
| | - Szilárd Varga
- Institute
of Organic Chemistry, Research Centre for
Natural Sciences, 2 Magyar tudósok krt., Budapest, H-1117, Hungary
| | - Tibor Soós
- Institute
of Organic Chemistry, Research Centre for
Natural Sciences, 2 Magyar tudósok krt., Budapest, H-1117, Hungary
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21
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Varga S, Angyal P, Martin G, Egyed O, Holczbauer T, Soós T. Total Syntheses of (-)-Minovincine and (-)-Aspidofractinine through a Sequence of Cascade Reactions. Angew Chem Int Ed Engl 2020; 59:13547-13551. [PMID: 32351014 PMCID: PMC7497198 DOI: 10.1002/anie.202004769] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/27/2020] [Indexed: 12/31/2022]
Abstract
We report 8‐step syntheses of (−)‐minovincine and (−)‐aspidofractinine using easily available and inexpensive reagents and catalyst. A key element of the strategy was the utilization of a sequence of cascade reactions to rapidly construct the penta‐ and hexacyclic frameworks. These cascade transformations included organocatalytic Michael‐aldol condensation, a multistep anionic Michael‐SN2 cascade reaction, and Mannich reaction interrupted Fischer indolization. To streamline the synthetic routes, we also investigated the deliberate use of steric effect to secure various chemo‐ and regioselective transformations.
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Affiliation(s)
- Szilárd Varga
- Institute of Organic Chemistry, Research Centre for Natural Sciences, 2 Magyar tudósok krt., 1117, Budapest, Hungary
| | - Péter Angyal
- Institute of Organic Chemistry, Research Centre for Natural Sciences, 2 Magyar tudósok krt., 1117, Budapest, Hungary
| | - Gábor Martin
- Institute of Organic Chemistry, Research Centre for Natural Sciences, 2 Magyar tudósok krt., 1117, Budapest, Hungary
| | - Orsolya Egyed
- Instrumentation Center, Research Centre for Natural Sciences, 2 Magyar tudósok krt., 1117, Budapest, Hungary
| | - Tamás Holczbauer
- Institute of Organic Chemistry, Research Centre for Natural Sciences, 2 Magyar tudósok krt., 1117, Budapest, Hungary.,Instrumentation Center, Research Centre for Natural Sciences, 2 Magyar tudósok krt., 1117, Budapest, Hungary
| | - Tibor Soós
- Institute of Organic Chemistry, Research Centre for Natural Sciences, 2 Magyar tudósok krt., 1117, Budapest, Hungary
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