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Reimche I, Yu H, Ariantari NP, Liu Z, Merkens K, Rotfuß S, Peter K, Jungwirth U, Bauer N, Kiefer F, Neudörfl JM, Schmalz HG, Proksch P, Teusch N. Phenanthroindolizidine Alkaloids Isolated from Tylophora ovata as Potent Inhibitors of Inflammation, Spheroid Growth, and Invasion of Triple-Negative Breast Cancer. Int J Mol Sci 2022; 23:ijms231810319. [PMID: 36142230 PMCID: PMC9499467 DOI: 10.3390/ijms231810319] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/16/2022] Open
Abstract
Triple-negative breast cancer (TNBC), representing the most aggressive form of breast cancer with currently no targeted therapy available, is characterized by an inflammatory and hypoxic tumor microenvironment. To date, a broad spectrum of anti-tumor activities has been reported for phenanthroindolizidine alkaloids (PAs), however, their mode of action in TNBC remains elusive. Thus, we investigated six naturally occurring PAs extracted from the plant Tylophora ovata: O-methyltylophorinidine (1) and its five derivatives tylophorinidine (2), tylophoridicine E (3), 2-demethoxytylophorine (4), tylophoridicine D (5), and anhydrodehydrotylophorinidine (6). In comparison to natural (1) and for more-in depth studies, we also utilized a sample of synthetic O-methyltylophorinidine (1s). Our results indicate a remarkably effective blockade of nuclear factor kappa B (NFκB) within 2 h for compounds (1) and (1s) (IC50 = 17.1 ± 2.0 nM and 3.3 ± 0.2 nM) that is different from its effect on cell viability within 24 h (IC50 = 13.6 ± 0.4 nM and 4.2 ± 1 nM). Furthermore, NFκB inhibition data for the additional five analogues indicate a structure–activity relationship (SAR). Mechanistically, NFκB is significantly blocked through the stabilization of its inhibitor protein kappa B alpha (IκBα) under normoxic as well as hypoxic conditions. To better mimic the TNBC microenvironment in vitro, we established a 3D co-culture by combining the human TNBC cell line MDA-MB-231 with primary murine cancer-associated fibroblasts (CAF) and type I collagen. Compound (1) demonstrates superiority against the therapeutic gold standard paclitaxel by diminishing spheroid growth by 40% at 100 nM. The anti-proliferative effect of (1s) is distinct from paclitaxel in that it arrests the cell cycle at the G0/G1 state, thereby mediating a time-dependent delay in cell cycle progression. Furthermore, (1s) inhibited invasion of TNBC monoculture spheroids into a matrigel®-based environment at 10 nM. In conclusion, PAs serve as promising agents with presumably multiple target sites to combat inflammatory and hypoxia-driven cancer, such as TNBC, with a different mode of action than the currently applied chemotherapeutic drugs.
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Affiliation(s)
- Irene Reimche
- Department of Biomedical Sciences, Institute of Health Research and Education, University of Osnabrück, 49090 Osnabrück, Germany
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Haiqian Yu
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Ni Putu Ariantari
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany
- Department of Pharmacy, Faculty of Mathematics and Natural Sciences, Udayana University, Bali 80361, Indonesia
| | - Zhen Liu
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Kay Merkens
- Department of Chemistry, University of Cologne, 50923 Cologne, Germany
| | - Stella Rotfuß
- Department of Biomedical Sciences, Institute of Health Research and Education, University of Osnabrück, 49090 Osnabrück, Germany
| | - Karin Peter
- Department of Biomedical Sciences, Institute of Health Research and Education, University of Osnabrück, 49090 Osnabrück, Germany
| | - Ute Jungwirth
- Department of Life Sciences, Centre for Therapeutic Innovation, University of Bath, Bath BA2 7AY, UK
| | - Nadine Bauer
- European Institute of Molecular Imaging, University of Münster, 48149 Münster, Germany
| | - Friedemann Kiefer
- European Institute of Molecular Imaging, University of Münster, 48149 Münster, Germany
- Max Planck Institute for Molecular Biomedicine, 48149 Münster, Germany
| | | | | | - Peter Proksch
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Nicole Teusch
- Department of Biomedical Sciences, Institute of Health Research and Education, University of Osnabrück, 49090 Osnabrück, Germany
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany
- Correspondence: ; Tel.: +49-211-81-14163
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Chacón-Huete F, Messina C, Cigana B, Forgione P. Diverse Applications of Biomass-Derived 5-Hydroxymethylfurfural and Derivatives as Renewable Starting Materials. CHEMSUSCHEM 2022; 15:e202200328. [PMID: 35652539 DOI: 10.1002/cssc.202200328] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/29/2022] [Indexed: 06/15/2023]
Abstract
This Review summarizes recent efforts to capitalize on 5-hydroxymethylfurfural (HMF) and related furans as emerging building blocks for the synthesis of fine chemicals and materials, with a focus on advanced applications within medicinal and polymer chemistry, as well as nanomaterials. As with all chemical industries, these fields have historically relied heavily on petroleum-derived starting materials, an unsustainable and polluting feedstock. Encouragingly, the emergent chemical versatility of biomass-derived furans has been shown to facilitate derivatization towards valuable targets. Continued work on the synthetic manipulation of HMF, and related derivatives, for access to a wide range of target compounds and materials is crucial for further development. Increasingly, biomass-derived furans are being utilized for a wide range of chemical applications, the continuation of which is paramount to accelerate the paradigm shift towards a sustainable chemical industry.
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Affiliation(s)
- Franklin Chacón-Huete
- Department of Chemistry and Biochemistry and Centre for Green Chemistry and Catalysis, Concordia University, 7141, rue Sherbrooke O., Montreal, QC, H4B 1R6, Canada
| | - Cynthia Messina
- Department of Chemistry and Biochemistry and Centre for Green Chemistry and Catalysis, Concordia University, 7141, rue Sherbrooke O., Montreal, QC, H4B 1R6, Canada
| | - Brandon Cigana
- Department of Chemistry and Biochemistry and Centre for Green Chemistry and Catalysis, Concordia University, 7141, rue Sherbrooke O., Montreal, QC, H4B 1R6, Canada
| | - Pat Forgione
- Department of Chemistry and Biochemistry and Centre for Green Chemistry and Catalysis, Concordia University, 7141, rue Sherbrooke O., Montreal, QC, H4B 1R6, Canada
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Mang Z, Zhang S, Bai J, Li M, Li H. Design, Synthesis and in Vitro Evaluation of Tylophorine Derivatives as Possible Antitumor Agents. Chem Biodivers 2020; 17:e2000066. [PMID: 32567792 DOI: 10.1002/cbdv.202000066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 06/19/2020] [Indexed: 11/07/2022]
Abstract
Structural simplification and modification of natural products are always very important resources to antitumor drugs. By introducing various aminomethyl groups and amide groups into the phenanthrene ring of tylophorine, a novel series of tylophorine derivatives have been designed and synthesized, and their antiproliferative activities against MCF-7, A549 and HepG-2 cells have been evaluated, too. The results indicated that most of the prepared compounds exhibited good antitumor activities. Especially, one compound with an {ethyl[2-(morpholin-4-yl)ethyl]amino}methyl group at the side chain exhibited the most significant cytotoxic effects.
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Affiliation(s)
- Zhiguo Mang
- State Key Laboratory of Bioengineering Reactor, Shanghai Key Laboratory of New Drug Design, and School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Shuai Zhang
- State Key Laboratory of Bioengineering Reactor, Shanghai Key Laboratory of New Drug Design, and School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Jing Bai
- State Key Laboratory of Bioengineering Reactor, Shanghai Key Laboratory of New Drug Design, and School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China.,School of Basic Medicine, Guizhou University of Traditional Chinese Medicine, Dongqing South Road, Guizhou, 550025, P. R. China
| | - Meijuan Li
- State Key Laboratory of Bioengineering Reactor, Shanghai Key Laboratory of New Drug Design, and School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Hao Li
- State Key Laboratory of Bioengineering Reactor, Shanghai Key Laboratory of New Drug Design, and School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
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Tylophorine: Sources, Properties, Applications and Biotechnological Production. PLANT-DERIVED BIOACTIVES 2020. [PMCID: PMC7211505 DOI: 10.1007/978-981-15-1761-7_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Tylophora indica, a medicinal climber, belongs to the family, Asclepiadaceae. Roots and leaves of the plant contain several alkaloids including tylophorine, tylophorinine and tylophrinidine. The major alkaloid, tylophorine found in T. indica possesses several properties, such as immunosuppressive, antitumour, antifeedant, antibacterial, antifungal, antiamoebic, diuretic and hepatoprotective activities. In addition to this, tylophorine provides positive stimulation to adrenal cortex. Biotechnological production of tylophorine was fulfilled by inducing hairy roots mediated by Agrobacterium rhizogenes (A4 strain). It was followed by its growth in liquid suspension culture that could yield maximum biomass and tylophorine production. This type of liquid suspension culture yielded 9.8 ± 0.21 mgL−1 tylophorine within 4–6 weeks of incubation. Maceration technique employed for the extraction of tylophorine was the most viable and efficient protocol. Although many reports are available regarding the biotechnological production of tylophorine, its competent and economic production still continues as a problematic issue.
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Fan W, Verrier C, Queneau Y, Popowycz F. 5-Hydroxymethylfurfural (HMF) in Organic Synthesis: A Review of its Recent Applications Towards Fine Chemicals. Curr Org Synth 2019; 16:583-614. [DOI: 10.2174/1570179416666190412164738] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 02/11/2019] [Accepted: 03/11/2019] [Indexed: 12/25/2022]
Abstract
Background:
5-Hydroxymethylfurfural (5-HMF) is a biomass-derived
platform chemical, which can be produced from carbohydrates. In the past decades, 5-
HMF has received tremendous attention because of its wide applications in the
production of various value-added chemicals, materials and biofuels. The manufacture
and the catalytic conversion of 5-HMF to simple industrially-important bulk chemicals
have been well reviewed. However, employing 5-HMF as a building block in organic
synthesis has never been summarized exclusively, despite the rapid development in this
area.
Objective:
The aim of this review is to bring a fresh perspective on the use of 5-HMF in
organic synthesis, to the exclusion of already well documented conversion of 5-HMF
towards relatively simple molecules such as 2,5-furandicarboxylic acid, 2,5-dimethylfuran and so on notably
used as monomers or biofuels.
Conclusion:
As it has been shown throughout this review, 5-HMF has been the object of numerous studies on
its use in fine chemical synthesis. Thanks to the presence of different functional groups on this platform
chemical, it proved to be an excellent starting material for the preparation of various fine chemicals. The use of
this C-6 synthon in novel synthetic routes is appealing, as it allows the incorporation of renewable carbonsources
into the final targets.
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Affiliation(s)
- Weigang Fan
- Universite de Lyon, ICBMS, UMR 5246, CNRS, Universite Lyon 1, INSA Lyon, CPE Lyon, Batiment Edgar Lederer, F-69622 Villeurbanne Cedex, France
| | - Charlie Verrier
- Universite de Lyon, ICBMS, UMR 5246, CNRS, Universite Lyon 1, INSA Lyon, CPE Lyon, Batiment Edgar Lederer, F-69622 Villeurbanne Cedex, France
| | - Yves Queneau
- Universite de Lyon, ICBMS, UMR 5246, CNRS, Universite Lyon 1, INSA Lyon, CPE Lyon, Batiment Edgar Lederer, F-69622 Villeurbanne Cedex, France
| | - Florence Popowycz
- Universite de Lyon, ICBMS, UMR 5246, CNRS, Universite Lyon 1, INSA Lyon, CPE Lyon, Batiment Edgar Lederer, F-69622 Villeurbanne Cedex, France
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Beil SB, Müller T, Sillart SB, Franzmann P, Bomm A, Holtkamp M, Karst U, Schade W, Waldvogel SR. Aktive Anode auf Molybdänbasis für dehydrierende Kupplungen. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201712718] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Sebastian B. Beil
- Institut für Organische Chemie; Johannes Gutenberg-Universität Mainz; Duesbergweg 10-14 55128 Mainz Deutschland
- MAterial Science IN MainZ (MAINZ); Exzellenzgraduiertenschule; Staudingerweg 9 55128 Mainz Deutschland
| | - Timo Müller
- Institut für Organische Chemie; Johannes Gutenberg-Universität Mainz; Duesbergweg 10-14 55128 Mainz Deutschland
| | - Sydney B. Sillart
- Institut für Organische Chemie; Johannes Gutenberg-Universität Mainz; Duesbergweg 10-14 55128 Mainz Deutschland
| | - Peter Franzmann
- Institut für Organische Chemie; Johannes Gutenberg-Universität Mainz; Duesbergweg 10-14 55128 Mainz Deutschland
| | - Alexander Bomm
- Fraunhofer Heinrich-Hertz-Institut; Abteilung Faseroptische Sensorsysteme; Am Stollen 19H 38640 Goslar Deutschland
| | - Michael Holtkamp
- Institut für Anorganische und Analytische Chemie; Westfälische Wilhelms Universität Münster; Corrensstraße 30 48149 Münster Deutschland
| | - Uwe Karst
- Institut für Anorganische und Analytische Chemie; Westfälische Wilhelms Universität Münster; Corrensstraße 30 48149 Münster Deutschland
| | - Wolfgang Schade
- Fraunhofer Heinrich-Hertz-Institut; Abteilung Faseroptische Sensorsysteme; Am Stollen 19H 38640 Goslar Deutschland
| | - Siegfried R. Waldvogel
- Institut für Organische Chemie; Johannes Gutenberg-Universität Mainz; Duesbergweg 10-14 55128 Mainz Deutschland
- MAterial Science IN MainZ (MAINZ); Exzellenzgraduiertenschule; Staudingerweg 9 55128 Mainz Deutschland
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7
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Beil SB, Müller T, Sillart SB, Franzmann P, Bomm A, Holtkamp M, Karst U, Schade W, Waldvogel SR. Active Molybdenum-Based Anode for Dehydrogenative Coupling Reactions. Angew Chem Int Ed Engl 2018; 57:2450-2454. [DOI: 10.1002/anie.201712718] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Sebastian B. Beil
- Institute of Organic Chemistry; Johannes Gutenberg University Mainz; Duesbergweg 10-14 55128 Mainz Germany
- Material Science in Mainz (MAINZ); Graduate School of Excellence; Staudingerweg 9 55128 Mainz Germany
| | - Timo Müller
- Institute of Organic Chemistry; Johannes Gutenberg University Mainz; Duesbergweg 10-14 55128 Mainz Germany
| | - Sydney B. Sillart
- Institute of Organic Chemistry; Johannes Gutenberg University Mainz; Duesbergweg 10-14 55128 Mainz Germany
| | - Peter Franzmann
- Institute of Organic Chemistry; Johannes Gutenberg University Mainz; Duesbergweg 10-14 55128 Mainz Germany
| | - Alexander Bomm
- Fraunhofer Heinrich-Hertz-Institut; Abteilung Faseroptische Sensorsysteme; Am Stollen 19H 38640 Goslar Germany
| | - Michael Holtkamp
- Institute of Inorganic and Analytical Chemistry; University of Münster; Corrensstrasse 30 48149 Münster Germany
| | - Uwe Karst
- Institute of Inorganic and Analytical Chemistry; University of Münster; Corrensstrasse 30 48149 Münster Germany
| | - Wolfgang Schade
- Fraunhofer Heinrich-Hertz-Institut; Abteilung Faseroptische Sensorsysteme; Am Stollen 19H 38640 Goslar Germany
| | - Siegfried R. Waldvogel
- Institute of Organic Chemistry; Johannes Gutenberg University Mainz; Duesbergweg 10-14 55128 Mainz Germany
- Material Science in Mainz (MAINZ); Graduate School of Excellence; Staudingerweg 9 55128 Mainz Germany
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Synthesis of substituted phenanthrene-9-benzimidazole conjugates: Cytotoxicity evaluation and apoptosis inducing studies. Eur J Med Chem 2017; 140:128-140. [PMID: 28923381 DOI: 10.1016/j.ejmech.2017.09.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/21/2017] [Accepted: 09/04/2017] [Indexed: 02/01/2023]
Abstract
A series of new phenanthrene-9-benzimidazole conjugates has been synthesized by condensing phenanthrene aldehydes with various substituted o-phenylenediamines. The title compounds were evaluated for their in vitro cytotoxic potential against various human cancer cell lines like breast (BT-549), prostate (PC-3 and DU145), triple negative breast cancer (MDA-MB-453), and human colon cancer (HCT-116 and HCT-15) cells. Among the tested compounds, 10o displayed significant in vitro cytotoxic activity against PC-3 prostate cancer cells with an IC50 value of 6.32 ± 0.09 μM. Further, the cell cycle analysis indicated that it blocks G2/M phase of the cell cycle in a dose dependent manner. In order to determine the effect of the compound 10o on cell viability; phase contrast microscopy, AO/EB staining, DAPI staining, and DCFDA staining studies were performed. In these studies, apoptotic features were clearly observed indicating that the compound inhibited cell proliferation by apoptosis. JC-1 staining and annexin binding assays indicated the extent of apoptosis in PC-3 cells. Further, relative viscosity measurements and molecular docking studies indicated that these compounds bind to DNA by intercalation.
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Glaser T, Fischer von Mollard G, Anselmetti D. Rational design of dinuclear complexes binding at two neighboring phosphate esters of DNA. Inorganica Chim Acta 2016. [DOI: 10.1016/j.ica.2016.02.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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10
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Kim YW, Georg GI. Boron-Heck reaction of cyclic enaminones: regioselective direct arylation via oxidative palladium(II) catalysis. Org Lett 2014; 16:1574-7. [PMID: 24650204 PMCID: PMC3993847 DOI: 10.1021/ol500105d] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
An oxidative boron-Heck reaction of cyclic enaminones with arylboronic acids is reported. This protocol provides a regioselective arylation at the C6 position of cyclic enaminones. When an N-carbamylated cyclic enaminone was employed, a switch to a conjugate addition reaction occurred in the presence of acid.
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Affiliation(s)
- Yong Wook Kim
- Department of Chemistry, Department of Medicinal Chemistry, and the Institute for Therapeutic Discovery and Development, University of Minnesota , 717 Delaware Street SE, Minneapolis, Minnesota 55414, United States
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11
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Yu YY, Georg GI. Biomimetic Aerobic C-H Olefination of Cyclic Enaminones at Room Temperature: Development toward the Synthesis of 1,3,5-Trisubstituted Benzenes. Adv Synth Catal 2014; 356:1359-1369. [PMID: 25071423 DOI: 10.1002/adsc.201300904] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A green and mild protocol for the dehydrogenative olefination of cyclic enaminones was devised via palladium catalysis at room temperature using oxygen as the terminal oxidant. The synthetic utility of the olefinated cyclic enaminones afforded a series of unique 1,3,5-trisubstituted benzenes via an unanticipated Diels-Alder tandem reaction. The broad substrate scope and good yields achieved with this new protocol provide an alternative pathway for arene functionalization.
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Affiliation(s)
- Yi-Yun Yu
- Department of Chemistry, Department of Medicinal Chemistry and the Institute for Therapeutics Discovery and Development, University of Minnesota, Twin Cities, 717 Delaware St SE, Minneapolis, Minnesota, USA
| | - Gunda I Georg
- Department of Chemistry, Department of Medicinal Chemistry and the Institute for Therapeutics Discovery and Development, University of Minnesota, Twin Cities, 717 Delaware St SE, Minneapolis, Minnesota, USA
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12
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Miguélez J, Boto A, Marín R, Díaz M. Simplification of antitumoral phenanthroindolizidine alkaloids: Short synthesis of cytotoxic indolizidinone and pyrrolidine analogs. Eur J Med Chem 2013; 66:540-54. [DOI: 10.1016/j.ejmech.2013.06.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 06/03/2013] [Accepted: 06/06/2013] [Indexed: 12/22/2022]
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13
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Yu YY, Bi L, Georg GI. Palladium-catalyzed direct C-H arylation of cyclic enaminones with aryl iodides. J Org Chem 2013; 78:6163-9. [PMID: 23750615 DOI: 10.1021/jo400830t] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A ligand-free method for the Pd-catalyzed direct arylation of cyclic enaminones using aryl iodides was developed. This method can be applied to a wide range of cyclic enaminones and aryl iodides with excellent C5-regioselectivity. Using widely available aryl iodides, the generality of this transformation provides easy access to a variety of 3-arylpiperidine structural motifs.
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Affiliation(s)
- Yi-Yun Yu
- Department of Chemistry, the Institute for Therapeutics Discovery and Development, University of Minnesota, 717 Delaware Street SE, Minneapolis, Minnesota 55414, United States
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Stoye A, Peez TE, Opatz T. Left, right, or both? On the configuration of the phenanthroindolizidine alkaloid tylophorine from Tylophora indica. JOURNAL OF NATURAL PRODUCTS 2013; 76:275-278. [PMID: 23369033 DOI: 10.1021/np300838w] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The alkaloid (-)-tylophorine was isolated from a sample of Tylophora indica, and the crude extract was analyzed by HPLC/MS(n) and chiral HPLC/MS. While the literature states that the naturally occurring form of this alkaloid is the R-enantiomer and that its S-antipode is usually not found in nature, we confirmed the hypothesis of Govindachari and Nagarajan that natural levorotatory tylophorine is indeed a nearly racemic mixture with a slight excess of the R-enantiomer.
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Affiliation(s)
- Alexander Stoye
- Institute of Organic Chemistry, Johannes Gutenberg-University, Duesbergweg 10-14, Mainz, Germany
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