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Methods of Lysergic Acid Synthesis—The Key Ergot Alkaloid. Molecules 2022; 27:molecules27217322. [PMID: 36364148 PMCID: PMC9654825 DOI: 10.3390/molecules27217322] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 10/10/2022] [Accepted: 10/21/2022] [Indexed: 11/30/2022] Open
Abstract
Ergot is the spore form of the fungus Claviceps purpurea. Ergot alkaloids are indole compounds that are biosynthetically derived from L-tryptophan and represent the largest group of fungal nitrogen metabolites found in nature. The common part of ergot alkaloids is lysergic acid. This review shows the importance of lysergic acid as a representative of ergot alkaloids. The subject of ergot and its alkaloids is presented, with a particular focus on lysergic acid. All methods of total lysergic acid synthesis—through Woodward, Hendrickson, and Szantay intermediates and Heck coupling methods—are presented. The topic of biosynthesis is also discussed.
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2
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Li W, Yu X, Yue Z, Zhang J. Asymmetric Construction of 2,3-Dihydroisoxazoles via an Organocatalytic Formal [3 + 2] Cycloaddition of Enynes with N-Hydroxylamines. Org Lett 2016; 18:3972-5. [DOI: 10.1021/acs.orglett.6b01737] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Wenbo Li
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Xiuzhao Yu
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Zhenting Yue
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Junliang Zhang
- Shanghai
Key Laboratory of Green Chemistry and Chemical Process, School of
Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Shanghai 200032, China
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Chandrasekhar B, Ahn S, Ryu JS. Synthesis of 4-Isoxazolines through Gold(I)-Catalyzed Cyclization of Propargylic N-Hydroxylamines. J Org Chem 2016; 81:6740-9. [DOI: 10.1021/acs.joc.6b01499] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- B. Chandrasekhar
- College of Pharmacy & Graduate School of Pharmaceutical Sciences, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-Gu, Seoul 03760, Republic of Korea
| | - Sewon Ahn
- College of Pharmacy & Graduate School of Pharmaceutical Sciences, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-Gu, Seoul 03760, Republic of Korea
| | - Jae-Sang Ryu
- College of Pharmacy & Graduate School of Pharmaceutical Sciences, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-Gu, Seoul 03760, Republic of Korea
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4
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Abstract
Various vinyl ketonitrones are prepared using new strategies and were applied to synthesize heterocycles in organic synthesis.
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Affiliation(s)
- Wei-Min Shi
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- Ministry of Education of China and School of Chemistry & Pharmaceutical Sciences
- Guangxi Normal University
- Guilin 541004
- China
| | - Xiao-Pan Ma
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- Ministry of Education of China and School of Chemistry & Pharmaceutical Sciences
- Guangxi Normal University
- Guilin 541004
- China
| | - Gui-Fa Su
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- Ministry of Education of China and School of Chemistry & Pharmaceutical Sciences
- Guangxi Normal University
- Guilin 541004
- China
| | - Dong-Liang Mo
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources
- Ministry of Education of China and School of Chemistry & Pharmaceutical Sciences
- Guangxi Normal University
- Guilin 541004
- China
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Mirza-Aghayan M, Molaee Tavana M, Boukherroub R. Direct oxidative synthesis of nitrones from aldehydes and primary anilines using graphite oxide and Oxone. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.08.049] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Chavda JK, Procopiou PA, Horton PN, Coles SJ, Porter MJ. Synthetic Studies Towards the Core Structure of Nakadomarin A by a Thioamide-Based Strategy. European J Org Chem 2014; 2014:129-139. [PMID: 24829538 PMCID: PMC4015372 DOI: 10.1002/ejoc.201301063] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Indexed: 11/29/2022]
Abstract
The tricyclic BCD substructure of the marine natural product nakadomarin A has been synthesised. The strategy utilised a key carbon-carbon bond-forming reaction between a furan and an N-acyliminium ion derived from a secondary thiolactam. In addition, a novel three-component coupling reaction between a thioamide, an allylic bromide and an isocyanate, leading to the establishment of two new stereogenic centres, is reported. Two key steps in a projected total synthesis of nakadomarin A have been realised by using the unique chemistry of thioamides. Formation of the carbocyclic B ring can be effected by nucleophilic attack of a furan on a thiolactam-derived iminium ion, and the key quaternary centre can be established by a novel three-component coupling reaction.
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Affiliation(s)
- Jai K Chavda
- Department of Chemistry, University College London Christopher Ingold Building, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Panayiotis A Procopiou
- GlaxoSmithKline Research & Development Limited, Medicines Research Centre Gunnels Wood Road, Stevenage, Hertfordshire, SG1 2NY, UK
| | - Peter N Horton
- UK National Crystallography Service, School of Chemistry, University of Southampton Southampton, SO17 1BJ, UK
| | - Simon J Coles
- UK National Crystallography Service, School of Chemistry, University of Southampton Southampton, SO17 1BJ, UK
| | - Michael J Porter
- Department of Chemistry, University College London Christopher Ingold Building, 20 Gordon Street, London, WC1H 0AJ, UK
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Zeng Q, Zhang L, Yang J, Xu B, Xiao Y, Zhang J. Pyrroles versus cyclic nitrones: catalyst-controlled divergent cyclization of N-(2-perfluoroalkyl-3-alkynyl) hydroxylamines. Chem Commun (Camb) 2014; 50:4203-6. [DOI: 10.1039/c4cc00493k] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Divergent cyclizations ofN-(2-(perfluoroalkyl)-3-alkynyl) hydroxylamines1have been realized by subtle choice of the catalyst under mild conditions, leading to two distinct types of synthetic valuable compounds, cyclic nitrones2and pyrroles3, in moderate to excellent yields.
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Affiliation(s)
- Qin Zeng
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai 200062, China
| | - Li Zhang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai 200062, China
| | - Jieru Yang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai 200062, China
| | - Bing Xu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai 200062, China
| | - Yuanjing Xiao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai 200062, China
| | - Junliang Zhang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- Department of Chemistry
- East China Normal University
- Shanghai 200062, China
- State Key Laboratory of Organometallic Chemistry
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Kim KH, Moon E, Kim SY, Choi SU, Lee JH, Lee KR. 4-Methylthio-butanyl derivatives from the seeds of Raphanus sativus and their biological evaluation on anti-inflammatory and antitumor activities. JOURNAL OF ETHNOPHARMACOLOGY 2013; 151:503-508. [PMID: 24231071 DOI: 10.1016/j.jep.2013.11.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 10/28/2013] [Accepted: 11/04/2013] [Indexed: 06/02/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Raphanus sativus seeds (Brassicaceae) known as Raphani Semen have long been used as anti-cancer and/or anti-inflammatory agents in Korean traditional medicine. This study was designed to isolate the bioactive constituents from the seed extracts of Raphanus sativus and evaluate their anti-inflammatory and antitumor activities. MATERIAL AND METHODS Bioassay-guided fractionation and chemical investigation of a methanolic extract of the seeds of Raphanus sativus led to the isolation and identification of seven 4-methylthio-butanyl derivatives. Structural elucidation of the isolated compounds was carried out using 1D and 2D nuclear magnetic resonance (NMR) spectroscopy techniques ((1)H, (13)C, COSY, HMQC and HMBC experiments) and mass spectrometry. RESULTS The isolated compounds were characterized as in the following: three new 4-methylthio-butanyl derivatives, sinapoyl desulfoglucoraphenin (1), (E)-5-(methylsulfinyl)pent-4-enoxylimidic acid methyl ester (2), and (S)-5-((methylsulfinyl)methyl)pyrrolidine-2-thione (3), together with four known compounds, 5-(methylsulfinyl)-4-pentenenitrile (4), 5-(methylsulfinyl)-pentanenitrile (5), sulforaphene (6), and sulforaphane (7). Full NMR data assignments of the three known compounds 4-6 were also reported for the first time. We evaluated the anti-neuroinflammatory effect of 1-7 in lipopolysaccharide-stimulated murine microglia BV2 cells. Compound 1 significantly inhibited nitrite oxide production with IC50 values of 45.36 μM. Moreover, it also reduced the protein expression of inducible nitric oxide synthase. All isolates were also evaluated for their antiproliferative activities against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15), and all of them showed antiproliferative activity against the HCT-15 cell, with IC50 values of 8.49-23.97 μM. CONCLUSIONS 4-Methylthio-butanyl derivatives were one of the main compositions of Raphanus sativus seeds, and activities demonstrated by the isolated compounds support the ethnopharmacological use of Raphanus sativus seeds (Brassicaceae) as anti-cancer and/or anti-inflammatory agents.
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Affiliation(s)
- Ki Hyun Kim
- Natural Products Laboratory, School of Pharmacy, Sungkyunkwan University, 300 Chonchon-dong, Jangan-ku, Suwon, Gyeonggi-do 440-746, Republic of Korea
| | - Eunjung Moon
- College of Pharmacy, Gachon University, #191 Hambakmoero, Yeonsu-gu, Incheon 406-799, Republic of Korea
| | - Sun Yeou Kim
- College of Pharmacy, Gachon University, #191 Hambakmoero, Yeonsu-gu, Incheon 406-799, Republic of Korea; Gachon Medical Research Institute, Gil Medical Center, Inchon 405-760, Republic of Korea
| | - Sang Un Choi
- Korea Research Institute of Chemical Technology, Teajeon 305-600, Republic of Korea
| | - Jei Hyun Lee
- College of Oriental Medicine, Dongguk University, Gyeong Ju 780-714, Republic of Korea
| | - Kang Ro Lee
- Natural Products Laboratory, School of Pharmacy, Sungkyunkwan University, 300 Chonchon-dong, Jangan-ku, Suwon, Gyeonggi-do 440-746, Republic of Korea.
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Han MY, Wang HZ, An WK, Jia JY, Ma BC, Zhang Y, Wang W. A concise synthesis of L-pyrrolysine. Chemistry 2013; 19:8078-81. [PMID: 23649505 DOI: 10.1002/chem.201300403] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Indexed: 11/05/2022]
Abstract
Organocatalysis: A concise synthesis of L-pyrrolysine has been accomplished in six steps from simple starting materials. The facile synthetic strategy relies on an organocatalytic Michael addition, an efficient amide coupling, and a challenging method for the imine-bond construction.
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Affiliation(s)
- Man-Yi Han
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, PR China
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Bardají N, Sánchez-Izquierdo F, Alibés R, Font J, Busqué F, Figueredo M. Flexible Approach to Stemona Alkaloids: Total Syntheses of (−)-Stemospironine and Three New Diastereoisomeric Analogs. Org Lett 2012; 14:4854-7. [DOI: 10.1021/ol302185j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nuria Bardají
- Universitat Autònoma de Barcelona, Departament de Química, 08193 Bellaterra, Spain
| | | | - Ramón Alibés
- Universitat Autònoma de Barcelona, Departament de Química, 08193 Bellaterra, Spain
| | - Josep Font
- Universitat Autònoma de Barcelona, Departament de Química, 08193 Bellaterra, Spain
| | - Félix Busqué
- Universitat Autònoma de Barcelona, Departament de Química, 08193 Bellaterra, Spain
| | - Marta Figueredo
- Universitat Autònoma de Barcelona, Departament de Química, 08193 Bellaterra, Spain
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Alemán J, Fraile A, Marzo L, Ruano JLG, Izquierdo C, Díaz-Tendero S. Enantioselective Synthesis of 4-Isoxazolines by 1,3-Dipolar Cycloadditions of Nitrones to Alkynals Catalyzed by Fluorodiphenylmethylpyrrolidines. Adv Synth Catal 2012. [DOI: 10.1002/adsc.201200033] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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12
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Buchlovič M, Hebanová S, Potáček M. 1,3-Dipolar cycloadditions of new 2,5-bifunctionalized five-membered cyclic nitrones. Tetrahedron 2012. [DOI: 10.1016/j.tet.2012.01.043] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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13
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Cheng P, Clive DLJ. Formation of Optically Pure Cyclic Amines by Intramolecular Conjugate Displacement. J Org Chem 2012; 77:3348-64. [DOI: 10.1021/jo3001657] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ping Cheng
- 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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Flores M, García P, Garrido NM, Nieto CT, Basabe P, Marcos IS, Sanz-González F, Goodman JM, Díez D. 1,3-Dipolar cycloaddition of nitrones with phenylvinyl sulfone. An experimental and theoretical study. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.tetasy.2012.01.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Affiliation(s)
- Ramon Alibés
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain, Fax: +34‐935811265
| | - Marta Figueredo
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain, Fax: +34‐935811265
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Fukuyama T, Inoue T, Yokoshima S. Synthetic Studies toward (+)-Lysergic Acid: Construction of the Tetracyclic Ergoline Skeleton. HETEROCYCLES 2009. [DOI: 10.3987/com-08-s(d)42] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Soldaini G, Cardona F, Goti A. Catalytic oxidation of imines based on methyltrioxorhenium/urea hydrogen peroxide: a mild and easy chemo- and regioselective entry to nitrones. Org Lett 2007; 9:473-6. [PMID: 17249790 DOI: 10.1021/ol062862w] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] The first successful catalytic oxidation procedure for the chemoselective conversion of imines to nitrones is reported. The reaction is general, high yielding, and user and environmentally friendly, and furnishes a solution to the yet unanswered issue of regioselective access to nitrones by oxidation of nitrogen derivatives.
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Affiliation(s)
- Gianluca Soldaini
- Dipartimento di Chimica Organica "Ugo Schiff", Laboratorio di Progettazione, Sintesi e Studio di Eterocicli Biologicamente Attivi (HeteroBioLab) and Consorzio INSTM, Università di Firenze, via della Lastruccia 13, I-50019 Sesto Fiorentino (Firenze), Italy
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Sánchez-Izquierdo F, Blanco P, Busqué F, Alibés R, de March P, Figueredo M, Font J, Parella T. Total Synthesis of the Putative Structure of Stemonidine: The Definitive Proof of Misassignment. Org Lett 2007; 9:1769-72. [PMID: 17397178 DOI: 10.1021/ol070486p] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[structure: see text] The total synthesis of the putative structure of the Stemona alkaloid stemonidine has been completed. The key transformations include a 1,3-dipolar cycloaddition of a chiral nitrone derived from (S)-prolinol and a spirolactonization process involving the generation of the critical stereocenter. The NMR data of the synthetic material do not match those reported for the natural product. It is concluded that the structure assigned to stemonidine is incorrect, and it must be reassigned as stemospironine.
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Curtis KL, Evinson EL, Handa S, Singh K. Asymmetric synthesis of 3-amino-4-hydroxy-2-(hydroxymethyl)pyrrolidines as potential glycosidase inhibitors. Org Biomol Chem 2007; 5:3544-53. [DOI: 10.1039/b711994a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Baran PS, Hafensteiner BD, Ambhaikar NB, Guerrero CA, Gallagher JD. Enantioselective Total Synthesis of Avrainvillamide and the Stephacidins. J Am Chem Soc 2006; 128:8678-93. [PMID: 16802835 DOI: 10.1021/ja061660s] [Citation(s) in RCA: 173] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this article, full details regarding our total synthesis of avrainvillamide and the stephacidins are presented. After an introduction and summary of prior synthetic studies in this family of structurally complex anticancer natural products, the evolution of a final synthetic approach is described. Thus, a thorough description of three separate model studies is provided for construction of the characteristic bicyclo[2.2.2]diazaoctane ring system common to these alkaloids. The first and second approaches sought to build the core using formal Diels-Alder and vinyl radical pathways, respectively. Although these strategies failed in their primary objective, they fostered the development of a new and mechanistically intriguing method for the synthesis of indolic enamides such as those found in numerous bioactive natural products. The scope and generality of this simple method for the direct dehydrogenation of tryptophan derivatives is described. Finally, details of a third and successful route to the core of these alkaloids are described which features oxidative C-C bond formation. Specifically, the first heterocoupling of two different types of carbonyl species (ester and amide) is accomplished in good yield, on a preparative scale, and with complete stereocontrol. The information gained in these model studies enabled an enantioselective total synthesis of stephacidin A. The absolute configuration of these alkaloids was firmly established in collaboration with Professor William Fenical. A full account of our successful efforts to convert stephacidin A into stephacidin B via avrainvillamide is presented. Finally, the first analogues of these natural products have been prepared and evaluated for anticancer activity.
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Affiliation(s)
- Phil S Baran
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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Hussaini SR, Moloney MG. 2,5-Disubstituted pyrrolidines: synthesis by enamine reduction and subsequent regioselective and diastereoselective alkylations. Org Biomol Chem 2006; 4:2600-15. [PMID: 16791325 DOI: 10.1039/b604183c] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Methodology for the diastereoselective synthesis of 2,5-disubstituted pyrrolidines by reduction of enamines derived from pyroglutamic acid is reported; the nature of nitrogen protection was found to be critical for the stereochemical control of the reaction outcome. Regioselective manipulation of the C-2 and C-5 substituents is possible, providing access to differently substituted pyrrolidines for a limited number of cases.
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Alibés R, Blanco P, Casas E, Closa M, de March P, Figueredo M, Font J, Sanfeliu E, Alvarez-Larena A. Asymmetric Synthesis of the Azabicyclic Core of the Stemona Alkaloids. J Org Chem 2005; 70:3157-67. [PMID: 15822978 DOI: 10.1021/jo047867q] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A general strategy for the construction of the 1-azabicyclo[5.3.0]decane core of Stemona alkaloids is developed. Our diversity-oriented approach exploits 1,3-dipolar cycloaddition of five-membered cyclic nitrones to C(6) olefins, followed by N-O reductive cleavage and azepine closure. The use of various enantiopure pyrroline N-oxides allows for a practical, stereoselective preparation of several putative precursors of different Stemona alkaloids.
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Affiliation(s)
- Ramon Alibés
- Departament de Química and Unitat de Cristallografia, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
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Clive DLJ, Huang X. Model Studies and First Synthesis of the Antifungal and Antibacterial Agent Cladobotryal. J Org Chem 2004; 69:1872-9. [PMID: 15058932 DOI: 10.1021/jo030284g] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The antifungal and antibacterial agent cladobotryal (1) was synthesized by a convergent route from lactone 31 and aldehyde 13, a key step in the elaboration of the pyridinone ring being conversion of a Boc group on nitrogen into a CO(2)SiPr-i(3) group. The simple model compounds 9 and 10, representing the core of cladobotryal and of 5, respectively, were prepared as support studies for making the natural product.
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Affiliation(s)
- Derrick L J Clive
- Chemistry Department, University of Alberta, Edmonton, Alberta, Canada T6G 2G2.
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Alibés R, Blanco P, de March P, Figueredo M, Font J, Álvarez-Larena Á, Piniella JF. Synthesis and 1,3-dipolar cycloadditions of a new enantiopure cyclic nitrone. Tetrahedron Lett 2003. [DOI: 10.1016/s0040-4039(02)02587-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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