501
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502
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Kuntiyong P, Akkarasamiyo S, Eksinitkun G. Short Synthetic Route toward the Tricyclic Core of Schulzeines. CHEM LETT 2006. [DOI: 10.1246/cl.2006.1008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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503
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Kim SH, Kim HG, Choo H, Cha JH, Pae AN, Koh HY, Chung BY, Cho YS. N-Acyliminium ion cyclizations of trimethylsilylmethylallenes. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.07.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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504
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He Y, Mahmud H, Moningka R, Lovely CJ, Dias HR. Cyclization reactions of N-acryloyl-2-aminobenzaldehyde derivatives: formal total synthesis of martinellic acid. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.06.104] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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505
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Ballini R, Palmieri A, Petrini M, Torregiani E. Solventless Clay-Promoted Friedel−Crafts Reaction of Indoles with α-Amido Sulfones: Unexpected Synthesis of 3-(1-Arylsulfonylalkyl) Indoles. Org Lett 2006; 8:4093-6. [PMID: 16928082 DOI: 10.1021/ol061604w] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Friedel-Crafts reaction of indoles with alpha-amido sulfones in the presence of montmorillonite K-10 leads unexpectedly to 3-(1-arylsulfonylalkyl) indoles in good yield. The obtained products can be further desulfonylated under reductive or alkylative conditions giving linear and branched 3-substituted indoles.
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Affiliation(s)
- Roberto Ballini
- Dipartimento di Scienze Chimiche, Università di Camerino, via S. Agostino 1, I-62032 Camerino, Italy
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506
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Nilson MG, Funk RL. Generation of N-Acyliminium Ions via Intramolecular Conjugate Addition Reactions: A Strategy for the Total Synthesis of Nakadomarin A. Org Lett 2006; 8:3833-6. [PMID: 16898829 DOI: 10.1021/ol061463y] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] The rapid construction of the tetracyclic core ring system of nakadomarin A via a tandem enecarbamate Michael addition/N-acyliminium ion cyclization is described.
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Affiliation(s)
- Mark G Nilson
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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507
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Mühlthau F, Stadler D, Goeppert A, Olah GA, Prakash GKS, Bach T. Chiral α-Branched Benzylic Carbocations: Diastereoselective Intermolecular Reactions with Arene Nucleophiles and NMR Spectroscopic Studies. J Am Chem Soc 2006; 128:9668-75. [PMID: 16866519 DOI: 10.1021/ja062102g] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The chiral benzylic alcohols 1-6 were prepared and subjected to S(N)1-type displacement reactions with various arene nucleophiles in acidic medium. Under optimized conditions (HBF(4).OEt(2), CH(2)Cl(2), -78 degrees C --> r.t.) the corresponding 1,1-diarylalkanes 11-18 and 20 were obtained in good chemical yields (48-99%). The facial diastereoselectivity of the reaction is high (d.r. = 91/9-97/3) when the substrate bears a stereogenic carbon center -CHtBuMe in the alpha-position to the electrophilic carbon atom. If the starting material was enantiomerically pure, no significant racemization was observed (94% ee --> 92% ee). The reactions proceed stereoconvergently as demonstrated by the conversion of the separated diastereoisomers syn-1a and anti-1a in separate reactions to the same product syn-11 (d.r. = 97/3). Further evidence for long-lived chiral benzylic carbocations as reaction intermediates was obtained from NMR studies in superacidic medium. The chiral cation 24 was generated in SO(2)ClF as the solvent at -70 degrees C employing SbF(5) as the Lewis acid and characterized by its (1)H and (13)C NMR spectra. NOE measurements suggest a preferred conformation in which the diastereotopic faces of the cation are differentiated by the two carbon substituents R and Me at the stereogenic carbon center in the alpha-position. The hypothesis is further supported by the observation that the diastereoselectivity of the substitution reaction decreases if the bulky tert-butyl (R = tBu) substituent in the substrate 1a is replaced by a smaller ethyl group (2a, R = Et).
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Affiliation(s)
- Friedrich Mühlthau
- Lehrstuhl für Organische Chemie I, Technische Universität München, D-85747 Garching, Germany
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508
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Nielsen TE, Le Quement S, Meldal M. Solid-phase synthesis of bicyclic dipeptide mimetics by intramolecular cyclization of alcohols, thiols, amines, and amides with N-acyliminium intermediates. Org Lett 2006; 7:3601-4. [PMID: 16092829 DOI: 10.1021/ol050871j] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A general strategy for the solid-phase synthesis of structurally diverse bicyclic dipeptide mimetics is presented. Depending on the amino acid side-chain (R(1)), peptide-derived N-acyliminium intermediates may undergo nucleophilic attack from either side-chain functional groups (-OH, -NH(2), -SH, and -CONH(2)) or the amide backbone (-CONH-) of the peptide, thus affording a range of aza-, thia-, and oxabicycloalkanes in excellent purity and diastereoselectivity. [reaction: see text]
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Affiliation(s)
- Thomas E Nielsen
- Carlsberg Laboratory, SPOCC Centre, Gamle Carlsberg Vej 10, DK-2500 Valby, Denmark
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509
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Tranchant MJ, Moine C, Othman RB, Bousquet T, Othman M, Dalla V. Eco-friendly N-acyliminium ion chemistry: solvent-free HNTf2 and TIPSOTf-catalyzed α-amidoalkylation of silicon-based π-nucleophiles. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.04.090] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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510
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Amat M, Escolano C, Gómez-Esqué A, Lozano O, Llor N, Griera R, Molins E, Bosch J. Stereoselective α-amidoalkylation of phenylglycinol-derived lactams. Synthesis of enantiopure 5,6-disubstituted 2-piperidones. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.tetasy.2006.05.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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511
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Gao S, Tu YQ, Hu X, Wang S, Hua R, Jiang Y, Zhao Y, Fan X, Zhang S. General and Efficient Strategy for Erythrinan and Homoerythrinan Alkaloids: Syntheses of (±)-3-Demethoxyerythratidinone and (±)-Erysotramidine. Org Lett 2006; 8:2373-6. [PMID: 16706529 DOI: 10.1021/ol0607185] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] A general and efficient strategy to both aromatic-type and nonaromatic-type erythrinan and homoerythrinan alkaloids has been developed. This approach involves a key two-step sequence, an alkylation of a ketone with various N-substituted iodoacetamides followed by a N-acyliminium ion promoted intramolecular cyclization, and represents one of the shortest routes to erythrinan and homoerythrinan alkaloids. As the application, the formal total synthesis of (+/-)-3-demethoxyerythratidinone and the total synthesis of (+/-)-erysotramidine have been achieved, respectively.
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Affiliation(s)
- Shuanhu Gao
- State Key Laboratory of Applied Organic Chemistry & Department of Chemistry, Lanzhou University, PRC
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512
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Liu L, Huang P. F3B · OEt2‐Promoted Intramolecular Si to C Phenyl Group Migration: A Highly Diastereoselective Synthesis of (4S,5S)‐4‐Hydroxy‐5‐phenyl‐2‐pyrrolidinone. SYNTHETIC COMMUN 2006. [DOI: 10.1080/00397910500503538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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513
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Zhang Y. Synthesis of vinylpyrroles, vinylfurans and vinylindoles via a Brønsted acid catalyzed highly regio- and stereoselective cis-hydroarylation of ynamides. Tetrahedron 2006. [DOI: 10.1016/j.tet.2005.11.079] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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514
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Stereoselective synthesis of trans-2,3-disubstituted pyrrolidines via addition to N-acyliminium ions. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.02.059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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515
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Hanessian S, Gauchet C, Charron G, Marin J, Nakache P. Design and Synthesis of Diversely Substituted Azacyclic Inhibitors of Endothelin Converting Enzyme. J Org Chem 2006; 71:2760-78. [PMID: 16555831 DOI: 10.1021/jo052649y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of azacyclic phosphonic acids were synthesized from L-pyroglutamic acid, 6-oxo-L-pipecolic acid, and their enantiomers. The objective was to study the effect of constraining acyclic inhibitors of endothelin converting enzyme on inhibitory activity. Potential pharmacophoric tethers were introduced by stereocontrolled reactions to give highly substituted pyrrolidine- and piperidine-alpha-phosphonic acids. Weak inhibitory activity was observed for one diastereomer in each series having the same relative orientation of substituents.
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Affiliation(s)
- Stephen Hanessian
- Department of Chemistry, Université de Montréal, C. P. 6128, Succ. Centre-Ville, Montréal, P. Q., Canada H3C 3J7.
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516
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Boesten JMM, Berkheij M, Schoemaker HE, Hiemstra H, Duchateau ALL. Enantioselective high-performance liquid chromatographic separation of N-methyloxycarbonyl unsaturated amino acids on macrocyclic glycopeptide stationary phases. J Chromatogr A 2006; 1108:26-30. [PMID: 16443231 DOI: 10.1016/j.chroma.2005.12.088] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Revised: 12/19/2005] [Accepted: 12/20/2005] [Indexed: 10/25/2022]
Abstract
This paper describes the enantiomeric resolution of a series of unsaturated N-methyloxycarbonyl-alpha-H-alpha-amino acids (N-MOC-alpha-amino acids) on macrocyclic glycopeptide stationary phases by means of high-performance liquid chromatography (HPLC). Three types of glycopeptide phases, i.e. Chirobiotic T, V and R, were evaluated in both reversed-phase (RP) and polar ionic mode (PIM). The best results in terms of enantioselectivity and resolution were obtained on Chirobiotic R phase, with the PIM mobile phase giving the highest resolution per min. Investigation of the pH of the reversed-phase mobile phase in the pH range 4.1-5.9 showed little effect on enantioselectivity. The method was applied for monitoring the conversion and product enantiomeric excess of an enzymatic hydrolysis reaction using N-MOC-alpha-H-alpha-amino acid esters as substrate.
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Affiliation(s)
- J M M Boesten
- DSM Pharma Chemicals, Department of Advanced Synthesis, Catalysis and Development, P.O. Box 18, 6160 MD Geleen, The Netherlands
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517
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Taylor MS, Jacobsen EN. Asymmetrische Katalyse durch chirale Wasserstoffbrückendonoren. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503132] [Citation(s) in RCA: 537] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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518
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Abstract
Mild and efficient AuCl3/AgOTf-catalyzed Pictet-Spengler reactions were developed to afford in good yields a variety of tetrahydroisoquinoline and tetrahydro-beta-carboline ring systems, which constitute important motifs in biologically active natural and synthetic organic compounds.
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Affiliation(s)
- So Won Youn
- Department of Chemistry, Pukyong National University, Busan 608-737, Korea.
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519
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Gilleron P, Millet R, Domarkas J, Farce A, Houssin R, Hénichart JP. Synthesis of a novel conformationally restricted Val-Phe dipeptidomimetic. J Pept Sci 2006; 12:140-6. [PMID: 15948143 DOI: 10.1002/psc.688] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A method for the synthesis of (3(R,S),6S,11b(R,S))-1,3,4,6,7,11b-hexahydro-4-oxo-3-phthalimidopyrido[2,1-a]isoquinoline-6-carboxylic acid 2 as a new conformationally restricted dipeptidomimetic of Val-Phe is reported. It involved cyclisation via an intramolecular electrophilic addition at the reactive bridgehead carbon. This new scaffold can be used as a building block in the preparation of libraries of peptidomimetics.
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Affiliation(s)
- Pauline Gilleron
- Institut de Chimie Pharmaceutique Albert Lespagnol, EA 2692, Université de Lille 2, BP 83, 59006 Lille, France
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520
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Belen’kii L, Gramenitskaya V, Evdokimenkova Y. The Literature of Heterocyclic Chemistry, Part IX, 2002–2004. ADVANCES IN HETEROCYCLIC CHEMISTRY 2006. [DOI: 10.1016/s0065-2725(06)92004-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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521
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P. Hsung R, Wang J, J. Swidorski J, Sydorenko N, A. Coverdale H, M. Kuyava J, Liu J. Aza-[3+3] Annulations. Part 6. Total Synthesis of Putative (-)-Lepadiformine and (-)-Cylindricine C. HETEROCYCLES 2006. [DOI: 10.3987/com-06-s(w)40] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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522
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Ijzendoorn DR, Botman PNM, Blaauw RH. Diastereoselective Cationic Tandem Cyclizations to N-Heterocyclic Scaffolds: Total Synthesis of (−)-Dysibetaine PP. Org Lett 2005; 8:239-42. [PMID: 16408884 DOI: 10.1021/ol052598r] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Herein, we report a short and diastereoselective synthesis of the natural product (-)-dysibetaine PP. The key step in the synthetic sequence is a novel highly diastereoselective tandem-cyclization reaction of an enantiomerically pure dipeptide. This cyclization methodology is applied in the synthesis of a broader range of N-heterocyclic scaffolds.
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523
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Lee SI, Park SY, Park JH, Jung IG, Choi SY, Chung YK, Lee BY. Rhodium N-Heterocyclic Carbene-Catalyzed [4 + 2] and [5 + 2] Cycloaddition Reactions. J Org Chem 2005; 71:91-6. [PMID: 16388622 DOI: 10.1021/jo051685u] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reactions: see text] A rhodium complex of N-heterocyclic carbene (NHC) has been developed for intra- and intermolecular [4 + 2] and intramolecular [5 + 2] cycloaddition reactions. This is the first use of a transition-metal NHC complex in a Diels-Alder-type reaction. For the intramolecular [4 + 2] cycloaddition reactions, all the dienynes studied were converted to their corresponding cycloadducts in 91-99% yields within 10 min. Moreover, up to 1900 turnovers have been obtained for the intramolecular [4 + 2] cycloaddition at 15-20 degrees C. For the intermolecular [4 + 2] cycloadditions, high yields (71-99%) of the corresponding cycloaddition products were obtained. The reaction time and yield were highly dependent upon the diene and the dienophile. For the intramolecular [5 + 2] cycloaddition reactions, all the alkyne vinylcyclopropanes studied were converted to their corresponding cycloadducts in 91-98% yields within 10 min. However, the catalytic system was not effective for an intermolecular [5 + 2] cycloaddition reaction.
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Affiliation(s)
- Sang Ick Lee
- Intelligent Textile System Research Center, Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul 151-747, Korea
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524
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Guinchard X, Vallée Y, Denis JN. tert-Butyl (Phenylsulfonyl)alkyl- N-hydroxycarbamates: The First Class of N-(Boc) Nitrone Equivalents. Org Lett 2005; 7:5147-50. [PMID: 16268524 DOI: 10.1021/ol051766c] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] tert-Butyl (phenylsulfonyl)alkyl-N-hydroxycarbamates 1 have been easily prepared from aldehydes and tert-butyl N-hydroxycarbamate in a methanol-water mixture using sodium benzenesulfinate and formic acid. These sulfones 1 behave as N-(Boc)-protected nitrones 4 in the reaction with organometallics to give N-(Boc)hydroxylamines. Some chemical transformations showing their interest as building blocks in organic synthesis are described.
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Affiliation(s)
- Xavier Guinchard
- Laboratoire d'Etudes Dynamiques et Structurales de la Sélectivité, UJF-CNRS, Institut de Chimie Moléculaire de Grenoble, Université Joseph Fourier, Grenoble 1, BP 53, 38041 Grenoble Cedex 9, France
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525
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Petrini M. α-Amido Sulfones as Stable Precursors of Reactive N-Acylimino Derivatives. Chem Rev 2005; 105:3949-77. [PMID: 16277367 DOI: 10.1021/cr050528s] [Citation(s) in RCA: 200] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marino Petrini
- Dipartimento di Scienze Chimiche, Università di Camerino, via S. Agostino, 1, I-62032 Camerino, Italy.
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526
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Petrini M, Torregiani E. TiCl4-promoted addition of nucleophiles to open chain α-amidoalkylphenyl sulfones. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.07.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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527
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Chiara JL, García A, Cristóbal-Lumbroso G. Ketone-imide versus ketone-oxime reductive cross-coupling promoted by samarium diiodide: new mechanistic insight gained from a failed aminocyclopentitol synthesis. J Org Chem 2005; 70:4142-51. [PMID: 15876107 DOI: 10.1021/jo050185y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] The intramolecular 1,6-ketone/imide reductive coupling promoted by samarium diiodide competes favorably with an alternative 1,5-ketone/oxime ether coupling in a keto-oxime substrate derived from D-glucosamine N-protected with a phthalimido group. This pinacol coupling reaction affords new homochiral alpha-hydroxylactam scaffolds that could be useful in diversity-oriented synthesis. A mechanistic proposal for this reaction that explains the experimental results is supported by DFT quantum-mechanical calculations on model compounds.
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Affiliation(s)
- Jose Luis Chiara
- Instituto de Química Orgánica General, CSIC, Juan de la Cierva 3, E-28006 Madrid, Spain.
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528
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529
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Zhang W, Zheng A, Liu Z, Yang L, Liu Z. A facile synthesis of isoindolo[2,1-a]quinolin-11-one via [4+2] reactions of N-acyliminium intermediates with olefines. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.06.097] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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530
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Hanessian S, Tremblay M, Marzi M, Del Valle JR. Synthetic studies in the intramolecular carbocyclization of N-acyloxyiminium ions. Stereoelectronic and steric implications of nucleophilic alkene, alkyne, and allene tethers. J Org Chem 2005; 70:5070-85. [PMID: 15960507 DOI: 10.1021/jo050326w] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
N-Acyloxyiminium ions generated from 4-substituted l-pyroglutamic esters with 4-(3-butenyl), 4-(3-butynyl), 4-(3-cinnamylmethyl), and 4-allenic tethers undergo rapid Lewis acid mediated carbocyclization to give stereodefined azacyclic compounds depending on the nature of the nucleophilic tether. In general, reactions of alkenes and alkynes with terminal alkyl or aryl substituents, as well as allenes, proceed through transient vinylic carbocations that are attacked internally by the N-Boc group to give tricyclic dihydrooxazinones. Diastereotopic bis-4-(3-butenyl) and 4-(3-butynyl) tethers undergo stereochemically controlled attack favoring an antiperiplanar rather than synclinal approach to give enantiopure 6-halo octahydroindole-2-carboxylic acids and 6-halo hexahydroindole-2-carboxylic acids as their methyl esters, respectively. The aza bicyclic and tricyclic compounds are excellent scaffolds for diversification.
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Affiliation(s)
- Stephen Hanessian
- Department of Chemistry, Université de Montréal, C.P. 6128, Station Centre-ville, Montréal, Province of Quebec, H3C 3J7 Canada.
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531
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Synthesis of 9-Oxo-9,13b-dihydro-7H-benzo[3,4]azepino[2,1-a]isoindole-6-carboxylic Acid Derivatives from Baylis-Hillman Adducts. B KOREAN CHEM SOC 2005. [DOI: 10.5012/bkcs.2005.26.7.1112] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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532
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Suga S, Tsutsui Y, Nagaki A, Yoshida JI. Cycloaddition of “N-Acyliminium Ion Pools” with Carbon–Carbon Multiple Bonds. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2005. [DOI: 10.1246/bcsj.78.1206] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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533
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Hucher N, Pesquet A, Netchitaïlo P, Daïch A. Exocyclic-EndocyclicN-Acyliminium Ion Equilibration via an Intramolecular α-Thioamidoalkylation in the Synthesis of Fused N,S-Heterocyclic Systems: Some New Parameters. European J Org Chem 2005. [DOI: 10.1002/ejoc.200400760] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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534
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Othman RB, Bousquet T, Fousse A, Othman M, Dalla V. Toward Improving the Chemistry of N-Acyliminium Ions: Nucleophilic Substitution Reactions of Pyrrolidinone Derivatives with Trialkylsilyl Nucleophiles Catalyzed by Triisopropylsilyltrifluoromethane Sulfonate (TIPSOTf). Org Lett 2005; 7:2825-8. [PMID: 15987146 DOI: 10.1021/ol050576z] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Nucleophilic substitution reactions of racemic and chiral 5-acetoxy-, 5-ethoxy-, and 5-methoxypyrrolidin-2-ones by silicon-based nucleophiles were efficiently catalyzed by TIPSOTf. This process was found to be general and accommodates a broad range of substrate-nucleophile combinations.
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Affiliation(s)
- Raja Ben Othman
- Unité de Recherche en Chimie Organique et Macromoléculaire, Faculté des Sciences et Techniques de l'Université du Havre, France
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535
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Nielsen TE, Meldal M. Solid-Phase Synthesis of Pyrroloisoquinolines via the Intramolecular N-Acyliminium Pictet−Spengler Reaction. ACTA ACUST UNITED AC 2005; 7:599-610. [PMID: 16004504 DOI: 10.1021/cc050008a] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the present investigation, solid-phase routes toward 1,5,6,10b-tetrahydro-2H-pyrrolo[2,1-a]isoquinolin-3-ones via the intramolecular N-acyliminium Pictet-Spengler reaction are established. Peptide aldehydes generated from their parent N-Boc 1,3-oxazines by acidic reaction conditions undergo intramolecular condensation reactions with the amide N of a solid-supported peptide backbone, thus forming a 1:1 epimeric mixture of a cyclic 5-hydroxylactam, which in turn is in equilibrium with the corresponding intermediate N-acyliminium ion. Provided appropriate acidic reaction conditions, a second ring may be appended via Pictet-Spengler cyclization from the aromatic ring of a neighboring phenylalanine derivative in the peptide sequence. The aromatic substitution pattern of the nucleophilic benzene ring of the phenylalanine derivative and the nature of the acidic reaction media are critically important for the course of the reaction, and both Lewis and Brønsted acids may be employed to effect the cyclization process. This intramolecular reaction is under strict control of stereoselectivity, and only a single stereoisomer is detected in the crude products. A range of mono-, di-, and trisubstituted phenylalanines with diverse sets of electron-donating and electron-withdrawing substituents, pyrene, and naphthalenes have successfully been brought within the scope of the reaction, thus providing a unique scaffold for combinatorial library synthesis.
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Affiliation(s)
- Thomas E Nielsen
- SPOCC Centre, Carlsberg Laboratory, Gamle Carlsberg Vej 10, DK-2500 Valby, Denmark
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536
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Marino JP, Zou N. Chemoselective Syntheses of γ-Butyrolactams Using Vinyl Sulfilimines and Dichloroketene. Org Lett 2005; 7:1915-7. [PMID: 15876018 DOI: 10.1021/ol050245m] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reactions between vinyl sulfilimines and dichloroketene generated in situ from trichloroacetyl chloride in the presence of zinc-copper couple give mixtures of alpha-dichloro-gamma-butyrolactams and alpha-dichloro-gamma-butyrolactone imines. Fine-tuning of substituents within vinyl sulfilimines results in reactions with good chemoselectivity and yield for lactams.
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Affiliation(s)
- Joseph P Marino
- Department of Chemistry and Biochemistry, University of Notre Dame, Indiana 46556, USA.
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537
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Popović-Đorđević JB, Ivanović MD, Kiricojević VD. A novel tandem process leading to functionalized glutarimides. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.02.087] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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538
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539
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540
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Ipaktschi J, Mohsseni-Ala J, Dülmer A, Loschen C, Frenking G. Reaction of Tungsten η1-Acetylide Complexes [(η5-C5H5)(NO)(CO)W−C⋮C−R]Li with Iminium Ions. Organometallics 2005. [DOI: 10.1021/om0491185] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Junes Ipaktschi
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany, and Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35043 Marburg, Germany
| | - Javad Mohsseni-Ala
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany, and Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35043 Marburg, Germany
| | - Ansgar Dülmer
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany, and Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35043 Marburg, Germany
| | - Christoph Loschen
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany, and Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35043 Marburg, Germany
| | - Gernot Frenking
- Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany, and Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, D-35043 Marburg, Germany
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541
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Dunetz JR, Ciccolini RP, Fröling M, Paap SM, Allen AJ, Holmes AB, Tester JW, Danheiser RL. Pictet–Spengler reactions in multiphasic supercritical carbon dioxide/CO2-expanded liquid media. In situ generation of carbamates as a strategy for reactions of amines in supercritical carbon dioxide. Chem Commun (Camb) 2005:4465-7. [PMID: 16136252 DOI: 10.1039/b508151c] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Acyl-Pictet-Spengler cyclizations can be achieved in scCO2/CO2-expanded liquid media via the in situ formation of carbamate derivatives of beta-arylethylamines.
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Affiliation(s)
- Joshua R Dunetz
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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542
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Karpov AS, Rominger F, Müller TJJ. A diversity oriented four-component approach to tetrahydro-β-carbolines initiated by Sonogashira coupling. Org Biomol Chem 2005; 3:4382-91. [PMID: 16327899 DOI: 10.1039/b511861a] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A consecutive four-component synthesis of highly-substituted tetrahydro-beta-carbolines can be achieved by a coupling-aminatio-aza-annulation-Pictet-Spengler (CAAPS) sequence creating five new sigma-bonds and four new stereocenters in a one-pot fashion. The structures were unambiguously supported by X-ray structure analyses.
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Affiliation(s)
- Alexei S Karpov
- Organisch-Chemisches Institut der Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany
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543
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Chen MD, He MZ, Zhou X, Huang LQ, Ruan YP, Huang PQ. Studies on the diastereoselective reductive alkylation of (R)-phenylglycinol derived phthalimide: observation of stereoelectronic effects. Tetrahedron 2005. [DOI: 10.1016/j.tet.2004.10.109] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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544
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Norton Matos M, Afonso CA, Batey RA. Synthesis of substituted pyrrolidines and piperidines from endocyclic enamine derivatives. Synthesis of (±)-laburnamine. Tetrahedron 2005. [DOI: 10.1016/j.tet.2004.11.035] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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545
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Meng WH, Wu TJ, Zhang HK, Huang PQ. Asymmetric syntheses of protected (2S,3S,4S)-3-hydroxy-4-methylproline and 4′-tert-butoxyamido-2′-deoxythymidine. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.10.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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546
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Hanessian S, Tremblay M. Tandem Functionalization of Nonactivated Alkenes and Alkynes in Intramolecular N-Acyloxyiminium Ion Carbocyclization. Synthesis of 6-Substituted Hydroindole 2-Carboxylic Acids. Org Lett 2004; 6:4683-6. [PMID: 15575660 DOI: 10.1021/ol040053b] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] Five-membered N-Boc acyliminium ions derived from L-pyroglutamic acid harboring 4-butenyl and 4-butynyl tethers undergo Lewis acid-mediated halo and tandem Friedel-Crafts carbocyclization within minutes at -78 degrees C to give stereodefined 6-substituted octahydroindole and hexahydroindole 2-carboxylic acid methyl esters, respectively. The cyclic vinyl bromides are excellent substrates for Pd-catalyzed Suzuki-Miyaura, Heck, and Stille couplings. The method also provides access to enantiopure sp2- and sp3-arylated azabicyclics that are novel and versatile scaffolds for chemical diversification.
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Affiliation(s)
- Stephen Hanessian
- Department of Chemistry, Université de Montréal, C.P. 6128, Station Centre-ville, Montréal, PQ, H3C 3J7 Canada.
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547
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Short diastereoselective synthesis of cis- and trans-hexahydropyrido[2,1-a]isoindole derivatives. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.10.045] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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548
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Bracca AB, Kaufman TS. Synthetic approaches to carnegine, a simple tetrahydroisoquinoline alkaloid. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.08.033] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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549
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Chen BF, Tasi MR, Yang CY, Chang JK, Chang NC. A versatile approach to 6-substituted-5-methoxy-δ-lactam framework and application to the formal synthesis of (±)-homopumiliotoxin 223G. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.09.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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550
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Karpov AS, Oeser T, Müller TJJ. A novel one-pot four-component access to tetrahydro-β-carbolines by a coupling-amination-aza-annulation-Pictet–Spengler sequence (CAAPS). Chem Commun (Camb) 2004:1502-3. [PMID: 15216351 DOI: 10.1039/b404559a] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The four-component coupling-amination-aza-annulation-Pictet-Spengler (CAAPS) sequence of acid chlorides 1, terminal alkynes 2, tryptamine derivatives 6, and acryloyl chloride derivatives 4 represents a facile and rapid one-pot access to tetrahydro-beta-carbolines 7 in moderate to good yields.
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Affiliation(s)
- Alexei S Karpov
- Organisch-Chemisches Institut der Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany
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