151
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Xin B. Phosphine-Free Cross-Coupling Reaction of Halopyridines with Arylboronic Acids in an Ionic Liquid: Water Mixture. JOURNAL OF CHEMICAL RESEARCH 2008. [DOI: 10.3184/030823408785702544] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Palladium acetate-catalysed Suzuki reaction of halopyridines and arylboronic acids has been investigated in room-temperature ionic liquids in the absence of the phosphine ligand. A significant effect of water on the efficiency of the Suzuki reaction in ionic liquids was observed. The mixture of ionic liquid and water significantly enhanced the rate of the coupling reaction. The separation of the product was easily performed by extraction with diethyl ether and the Pd(OAc)2–[bmim][PF6] (1-butyl-3-methylimidazolium hexafluorophosphate) can be reused six times with only a small loss of reactivity.
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Affiliation(s)
- Bingwei Xin
- Department of Chemistry, Dezhou University, Dezhou 253023, P. R. China
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152
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Tymoshenko D. Chapter 1 Benzoheteropines with Fused Pyrrole, Furan and Thiophene Rings. ADVANCES IN HETEROCYCLIC CHEMISTRY 2008. [DOI: 10.1016/s0065-2725(07)00001-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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153
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Affiliation(s)
- Toh-Seok Kam
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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154
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Baudoin O. Synthesis of tubulin-binding bridged biaryls via intermolecular Suzuki coupling. CR CHIM 2008. [DOI: 10.1016/j.crci.2007.02.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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155
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Fauq AH, Simpson K, Maharvi GM, Golde T, Das P. A multigram chemical synthesis of the gamma-secretase inhibitor LY411575 and its diastereoisomers. Bioorg Med Chem Lett 2007; 17:6392-5. [PMID: 17897827 PMCID: PMC2962444 DOI: 10.1016/j.bmcl.2007.07.062] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Revised: 07/18/2007] [Accepted: 07/19/2007] [Indexed: 12/21/2022]
Abstract
An improved chemical synthesis of N-2((2S)-2-(3,5-difluorophenyl)-2-hydroxyethanoyl)-N1-((7S)-5-methyl-6-oxo-6,7-dihydro-5H-dibenzo[b,d]azepin-7-yl)-l-alaninamide (LY411,575, 9a), a known gamma-secretase inhibitor, is described. The key synthetic steps, which used no chiral chromatography in the entire sequence, involved (1) improved microwave-assisted synthesis of a seven-membered lactam (+/-)-(5,7-dihydro-6H-dibenz-[b,d]azepin-6-one 2, and (2) convenient isolation of pure LY411575 from a mixture of four diastereomers by simple flash silica gel chromatography. Starting from the resolved aminolactams 5a and 5b, all four diastereomers were produced in enantiomerically pure form.
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Affiliation(s)
- Abdul H Fauq
- Department of Neuroscience, Mayo Clinic Jacksonville, 4500 San Pablo Road, Jacksonville, FL 32224, USA.
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156
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157
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Synthesis of fluorescent tetracyclic lactams by a “one pot” three steps palladium-catalyzed borylation, Suzuki coupling (BSC) and lactamization. J Photochem Photobiol A Chem 2007. [DOI: 10.1016/j.jphotochem.2007.03.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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158
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Pflantz R, Tielmann P, Rössle M, Hoenke C, Christoffers J. Eight-Membered-Ring Lactams – New Scaffolds for Combinatorial Chemistry Prepared by Ring-Expansion of 1,4-Diketones with Primary Amines. European J Org Chem 2007. [DOI: 10.1002/ejoc.200700263] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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159
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Joncour A, Décor A, Liu JM, Dau METH, Baudoin O. Asymmetric Synthesis of Antimicrotubule Biaryl Hybrids of Allocolchicine and Steganacin. Chemistry 2007; 13:5450-65. [PMID: 17352448 DOI: 10.1002/chem.200601764] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The asymmetric synthesis of novel axially chiral biaryl compounds 5 a-f containing a seven- or eight-membered heterocyclic medium ring is described. These molecules can be considered to be structural hybrids of allocolchicine- and steganacin-type natural products. The synthesis featured an atropo-diastereoselective biaryl Suzuki coupling in which a benzylic stereocenter efficiently transferred its stereochemical information to the biaryl axis. The coupling conditions were optimized, and two biphenylphosphane ligands (DavePhos and S-Phos) were found to give the highest yields and diastereoselectivities. A three-element stereochemical model was proposed to explain the observed diastereoselectivities. In a second key step, the medium ring of the target molecules was formed by a stereoselective S(N)1-type cyclodehydration that probably involved a configurationally stable carbocationic intermediate, as supported by calculations. Alternatively, S(N)2-type cyclizations were employed on the same Suzuki coupling products to give the target molecules in a stereodivergent or stereoconvergent manner. These cyclization methods furnished the target hybrid analogues 5 a-f with ee values above 94 %. All analogues were evaluated as antimicrotubule agents and against a panel of cancer-cell lines using colchicine (1) and N-acetylcolchinol (3) as references. Promising activities were found for R,aR-configured compounds 5 a, b and 5 f; in particular, ethyl analogue 5 b showed a twofold antimicrotubule activity relative to colchicine.
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Affiliation(s)
- Agnès Joncour
- Institut de Chimie des Substances Naturelles, CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette, France
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160
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Ma N, Zhu Z, Wu Y. Cyclopalladated ferrocenylimine: a highly effective catalyst for the borylation/suzuki coupling reaction. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.03.108] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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161
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Joucla L, Popowycz F, Lozach O, Meijer L, Joseph B. Access to Paullone Analogues by IntramolecularHeck Reaction. Helv Chim Acta 2007. [DOI: 10.1002/hlca.200790076] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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162
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Bonneau AL, Robert N, Hoarau C, Baudoin O, Marsais F. A new synthetic approach to biaryls of the rhazinilam type. Application to synthesis of three novel phenylpyridine-carbamate analogues. Org Biomol Chem 2007; 5:175-83. [PMID: 17164923 DOI: 10.1039/b613173e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis of three novel racemic phenylpyridine-carbamate analogues of rhazinilam and their biological evaluation as inhibitors of microtubule assembly and disassembly by interaction with tubulin are described. The sterically hindered ortho-disubstituted biaryl unit as the challenging key structural element is first obtained by a sequential regiocontrolled nucleophilic addition of a lithium ortho-lithiohomobenzylic alkoxide species to 3-bromo-5-oxazolyl pyridine as the electrophile and a subsequent oxidation step. The incorporation of the amino group by replacement of the bromide has been achieved using a Buchwald-Hartwig amination coupling. Ultimate deprotection steps furnished free-amino and free-hydroxyl appendages which were connected by phosgenation to furnish the nine-membered median carbamate ring.
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Affiliation(s)
- Anne-Laure Bonneau
- Laboratoire de Chimie Organique Fine et Hétérocyclique UMR 6014, Université et INSA de Rouen, Place E. Blondel, 76131, Mont Saint Aignan, France
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163
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Wu WY, Chen SN, Tsai FY. Recyclable and highly active cationic 2,2′-bipyridyl palladium(II) catalyst for Suzuki cross-coupling reaction in water. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.10.127] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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164
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165
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Sommer W, Weck M. Poly(norbornene)-Supported N-Heterocyclic Carbenes as Ligands in Catalysis. Adv Synth Catal 2006. [DOI: 10.1002/adsc.200606135] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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166
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Ram RN, Singh V. Palladium(II) chloride/EDTA-catalyzed biaryl homo-coupling of aryl halides in aqueous medium in the presence of ascorbic acid. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.08.056] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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167
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Mentzel UV, Tanner D, Tønder JE. Comparative Study of the Kumada, Negishi, Stille, and Suzuki−Miyaura Reactions in the Synthesis of the Indole Alkaloids Hippadine and Pratosine. J Org Chem 2006; 71:5807-10. [PMID: 16839172 DOI: 10.1021/jo060729b] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The total synthesis of hippadine by a tandem metalation/cross-coupling/lactamization strategy was investigated starting from either 7-bromoindole or a 6-halogenated methyl piperonate. The Kumada and Negishi cross-coupling reactions failed to provide any of the desired product. However, the Stille and Suzuki reactions furnished hippadine in low yields starting from the electron-deficient methyl 6-iodo- and 6-bromopiperonate, respectively. Starting from the metalated indole, only the Suzuki reaction occurred, affording hippadine in 67-74% and pratosine in 62% isolated yield.
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Affiliation(s)
- Uffe V Mentzel
- Department of Chemistry, Technical University of Denmark, Building 201, Kemitorvet, DK-2800 Kgs. Lyngby, Denmark
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168
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Liu L, Zhang Y, Xin B. Synthesis of Biaryls and Polyaryls by Ligand-Free Suzuki Reaction in Aqueous Phase. J Org Chem 2006; 71:3994-7. [PMID: 16674083 DOI: 10.1021/jo060122v] [Citation(s) in RCA: 163] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A highly efficient palladium acetate-catalyzed ligand-free Suzuki reaction in aqueous phase was developed in short reaction times (0.5-1 h) at 35 degrees C in air. The key for such a successful catalytic system was the use of a suitable amount of cosolvents in the aqueous phase. The method could be extended to the consecutive multi-Suzuki coupling, and polyaryls were prepared in a single one-pot step in high selectivity and excellent yield under mild reaction conditions (60 degrees C).
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Affiliation(s)
- Leifang Liu
- Department of Chemistry, Zhejiang University, Hangzhou 310027, People's Republic of China
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169
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Joucla L, Putey A, Joseph B. Synthesis of fused heterocycles with a benzazepinone moiety via intramolecular Heck coupling. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.09.122] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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170
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Affiliation(s)
- Olivier Baudoin
- Institut de Chimie des Substances Naturelles, CNRS, Avenue de la Terrasse, 91198 Gif‐sur‐Yvette, France, Fax: +33‐1‐69077247
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171
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Liu L, Zhang Y, Wang Y. Phosphine-free palladium acetate catalyzed Suzuki reaction in water. J Org Chem 2005; 70:6122-5. [PMID: 16018716 DOI: 10.1021/jo050724z] [Citation(s) in RCA: 175] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pd(OAc)(2) in a mixture of water and poly(ethylene glycol) (PEG) is shown to be an extremely active catalyst for the Suzuki reaction of aryl iodides and bromides. The reaction can be conducted under mild conditions (50 degrees C) without the use of a microwave or phosphine ligand in high yields. The isolation of the products is readily performed by the extraction of diethyl ether, and the Pd(OAc)(2)-PEG can be reused without significant loss in activity.
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Affiliation(s)
- Leifang Liu
- Department of Chemistry, Zhejiang University, Hangzhou 310027, P.R. China
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172
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Abreu AS, Ferreira PMT, Queiroz MJRP, Ferreira ICFR, Calhelha RC, Estevinho LM. Synthesis of β-Benzo[b]thienyldehydrophenylalanine Derivatives by One-Pot Palladium-Catalyzed Borylation and Suzuki Coupling (BSC) and Metal-Assisted Intramolecular Cyclization - Studies of Fluorescence and Antimicrobial Activity. European J Org Chem 2005. [DOI: 10.1002/ejoc.200500040] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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173
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Bremner JB, Sengpracha W. An iodoacetamide-based free radical cyclisation approach to the 7,12-dihydro-indolo[3,2-d][1]benzazepin-6(5H)-one (paullone) system. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.03.133] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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174
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Appukkuttan P, Dehaen W, Van der Eycken E. Microwave-Enhanced Synthesis of N-Shifted Buflavine Analogues via a Suzuki−Ring-Closing Metathesis Protocol. Org Lett 2005; 7:2723-6. [PMID: 15957931 DOI: 10.1021/ol050806+] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] A novel, microwave-enhanced six-step synthesis was devised for the synthesis of N-shifted buflavine analogues. Microwave-enhanced Suzuki-Miyaura cross-coupling and ring-closing metathesis reactions were used as the key steps. Microwave irradiation was found to enhance the ring-closing metathesis reaction to generate the otherwise difficultly obtainable medium-sized ring system of the target molecules.
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Affiliation(s)
- Prasad Appukkuttan
- Department of Chemistry, University of Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
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175
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Gug F, Blondel M, Desban N, Bouaziz S, Vierfond JM, Galons H. An expeditious synthesis of 6-aminophenanthridines. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.03.135] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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176
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Tao B, Boykin DW. Simple amine/Pd(OAc)(2)-catalyzed suzuki coupling reactions of aryl bromides under mild aerobic conditions. J Org Chem 2005; 69:4330-5. [PMID: 15202886 DOI: 10.1021/jo040147z] [Citation(s) in RCA: 160] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new palladium catalyst (DAPCy) made from Pd(OAc)(2) and commercially available, inexpensive dicyclohexylamine has been developed for the Suzuki coupling reaction of aryl bromides with boronic acids to give the coupling products in good to high yields. The air-stable catalyst was characterized and well-defined by X-ray crystallography. A catalytic system involving DAPCy in dioxane demonstrates a temperature-dependent reactivity toward aryl bromides with different electronic substituents, and selectively couples electron-deficient aryl bromides with boronic acids over electron-rich ones at room temperature. Another catalytic system employing DAPCy in EtOH provides a general and convenient method to prepare biaryls from aryl bromides and boronic acids with a broad range of functional groups at room temperature and under aerobic conditions.
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Affiliation(s)
- Bin Tao
- Department of Chemistry, MSC 8L0378, Georgia State University, 33 Gilmer Street, SE Unit 8, Atlanta, Georgia 30303-3088, USA
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177
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Best JD, Jay MT, Otu F, Ma J, Nadin A, Ellis S, Lewis HD, Pattison C, Reilly M, Harrison T, Shearman MS, Williamson TL, Atack JR. Quantitative measurement of changes in amyloid-beta(40) in the rat brain and cerebrospinal fluid following treatment with the gamma-secretase inhibitor LY-411575 [N2-[(2S)-2-(3,5-difluorophenyl)-2-hydroxyethanoyl]-N1-[(7S)-5-methyl-6-oxo-6,7-dihydro-5H-dibenzo[b,d]azepin-7-yl]-L-alaninamide]. J Pharmacol Exp Ther 2005; 313:902-8. [PMID: 15743924 DOI: 10.1124/jpet.104.081174] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The efficacy of gamma-secretase inhibitors in vivo has, to date, been generally assessed in transgenic mouse models expressing increased levels of amyloid-beta (Abeta) peptide thereby allowing the detection of changes in Abeta production. However, it is not clear whether the in vivo potency of gamma-secretase inhibitors is independent of the level of amyloid precursor protein expression. In other words, does a gamma-secretase inhibitor have the same effect in nontransgenic physiological animals versus transgenic overexpressing animals? In the present study, an immunoassay has been developed which can detect Abeta(40) in the rat brain, where concentrations are much lower than those seen in transgenic mice such as Tg2576 (c. 0.7 and 25 nM, respectively) and in cerebrospinal fluid (CSF, c. 0.3 nM). Using this immunoassay, the effects of the gamma-secretase inhibitor LY-411575 [N(2)-[(2S)-2-(3,5-difluorophenyl)-2-hydroxyethanoyl]-N(1)-[(7S)-5-methyl-6-oxo-6,7-dihydro-5H-dibenzo[b,d]azepin-7-yl]-L-alaninamide] were assessed and robust dose-dependent reductions in rat brain and CSF Abeta(40) levels were observed with ID(50) values of 1.3 mg/kg for both brain and CSF. These values were comparable with those calculated for LY-411575 in transgenic mice. Time course experiments using LY-411575 demonstrated comparable temporal reductions in rat brain and CSF Abeta(40), further suggesting these two pools of Abeta are related. Accordingly, when all the data for the dose-response curve and time course were correlated, a strong association was observed between the brain and CSF Abeta(40) levels. These data demonstrate the utility of the rat as a novel approach for assessing the effects of gamma-secretase inhibitors on central nervous system Abeta(40) levels in vivo.
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Affiliation(s)
- Jonathan D Best
- Department of In Vivo Neuroscience, The Neuroscience Research Centre, Merck Sharp and Dohme Research Laboratories, Essex, UK.
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178
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Evidente A, Andolfi A, Vurro M, Fracchiolla M, Zonno MC, Motta A. Drazepinone, a trisubstituted tetrahydronaphthofuroazepinone with herbicidal activity produced by Drechslera siccans. PHYTOCHEMISTRY 2005; 66:715-721. [PMID: 15771896 DOI: 10.1016/j.phytochem.2005.02.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2004] [Revised: 02/07/2005] [Indexed: 05/24/2023]
Abstract
When grown in a minimal-defined medium, a strain of Drechslera siccans, a pathogenic fungus isolated from seeds of Lolium perenne, produced phytotoxic metabolites. This strain is one of the best toxin producers among several grass pathogenic fungal strains collected and tested to find phytotoxins to be used as natural herbicides of monocot weeds. From the culture filtrates of D. siccans, we isolated a new phytotoxic trisubstituted naphthofuroazepinone, named drazepinone, and characterised it as a 3,5,12a-trimethyl-2,5,5a,12a-tetrahydro-1H-naphtho[2',3':4,5]furo[2,3-b]azepin-2-one. Assayed at 2 microg microl(-1) solution the novel metabolite proved to have broad-spectrum herbicidal properties, without antibacterial and antifungal activities, and low zootoxic activity. Its original chemical structure and the interesting biological properties make drazepinone a potential natural herbicide.
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Affiliation(s)
- Antonio Evidente
- Dipartimento di Scienze del Suolo della Pianta e dell'Ambiente, Università di Napoli Federico II, Via Università 100, I-80055 Portici, Italy.
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179
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Applied Suzuki cross-coupling reaction for syntheses of biologically active compounds. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s0169-3158(06)80004-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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180
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Raw SA, Taylor RJ. Cascade reactions of 1,2,4-triazines: direct thermochemical access to functionalized 4,5-dihydroazocines. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.09.169] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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181
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Navarro O, Oonishi Y, Kelly RA, Stevens ED, Briel O, Nolan SP. General and efficient methodology for the Suzuki–Miyaura reaction in technical grade 2-propanol. J Organomet Chem 2004. [DOI: 10.1016/j.jorganchem.2004.04.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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182
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Prieto M, Zurita E, Rosa E, Muñoz L, Lloyd-Williams P, Giralt E. Arylboronic Acids and Arylpinacolboronate Esters in Suzuki Coupling Reactions Involving Indoles. Partner Role Swapping and Heterocycle Protection. J Org Chem 2004; 69:6812-20. [PMID: 15387606 DOI: 10.1021/jo0491612] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Yields of Suzuki couplings involving indoles depended upon (i) whether arylboronic acids or arylpinacolboronate esters were used, (ii) whether the heterocycle was the aryl halide or the arylboron coupling partner, and (iii) whether the heterocycle was protected or not. Highest yields, which were unaffected by incorporating Boc or Tos protection at the heterocyclic nitrogen, were obtained when indole bromides were reacted with phenylboronic acids. When indolylboronic acids were reacted with phenyl bromides, yields were somewhat lower and depended on the nitrogen substituent, being highest in the absence of protection, lower in the presence of the Boc group, and lowest of all with the Tos group. Arylpinacolboronate esters were less reactive than arylboronic acids. They required considerably longer reaction times and furnished generally lower yields of biaryl. Furthermore, irrespective of whether the heterocycle was the aryl bromide or the arylpinacolboronate ester, these yields were highest when it was protected with the Tos group. Yields were lower with the Boc group, and unprotected heterocycles gave only traces of biaryl. Careful selection of arylboron reagent, of coupling partner roles, and of protecting groups are essential to ensuring optimum results in these Suzuki couplings. These results may also be relevant to couplings involving other substrates.
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Affiliation(s)
- Monica Prieto
- Department of Organic Chemistry, Universitat de Barcelona, Martí i Franquès, 1-11, Barcelona E-08028, Spain
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183
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Navarro O, Kaur H, Mahjoor P, Nolan SP. Cross-Coupling and Dehalogenation Reactions Catalyzed by (N-Heterocyclic carbene)Pd(allyl)Cl Complexes. J Org Chem 2004; 69:3173-80. [PMID: 15104459 DOI: 10.1021/jo035834p] [Citation(s) in RCA: 297] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of well-defined, air- and moisture-stable (NHC)Pd(allyl)Cl (NHC = N-heterocyclic carbene) complexes has been used in several catalytic reactions: Suzuki-Miyaura cross-coupling, catalytic dehalogenation of aryl halides, and aryl amination. The scope of the three processes using various substrates was examined. A general system involving the use of (IPr)Pd(allyl)Cl as catalyst and NaO(t)Bu as base has proven to be highly active for the Suzuki-Miyaura cross-coupling of activated and unactivated aryl chlorides and bromides, for the catalytic dehalogenation of aryl chlorides, and for the catalytic aryl amination of aryl triflates. All reactions proceed in short reaction times and at mild temperatures. The system has also proven to be compatible with the microwave-assisted Suzuki-Miyaura cross-coupling and catalytic dehalogenation processes, affording yields similar to those of the conventionally heated analogous reactions.
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Affiliation(s)
- Oscar Navarro
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, USA
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184
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Fuwa H, Okamura Y, Morohashi Y, Tomita T, Iwatsubo T, Kan T, Fukuyama T, Natsugari H. Highly efficient synthesis of medium-sized lactams via intramolecular Staudinger–aza-Wittig reaction of ω-azido pentafluorophenyl ester: synthesis and biological evaluation of LY411575 analogues. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.01.087] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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185
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Cacchi S, Arcadi A, Fabrizi G, Marinelli F, M. Parisi L. 2-(o-Aminoaryl)indole Derivatives via the Coupling-Cyclization of o-Alkynylanilines with o-Halotrifluoroacetanilides in the Presence of a Palladium Catalyst. HETEROCYCLES 2004. [DOI: 10.3987/com-04-s(p)23] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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186
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Kwong FY, Chan KS, Yeung CH, Chan ASC. An active ferrocenyl triarylphosphine for palladium-catalyzed Suzuki–Miyaura cross-coupling of aryl halides. Chem Commun (Camb) 2004:2336-7. [PMID: 15490008 DOI: 10.1039/b407661c] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pd-catalyzed Suzuki-Miyaura reaction of aryl chlorides was accomplished through the use of an active ferrocene-based triarylphosphine ligand. This air- and moisture-stable ligand was found to be effective for the cross-coupling of aryl halides at room temperature to 115 degrees C.
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Affiliation(s)
- Fuk Yee Kwong
- Open Laboratory of Chirotechnology of the Institute of Molecular Technology for Drug Discovery and Synthesis, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Hong Kong.
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187
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Navarro O, Kelly RA, Nolan SP. A General Method for the Suzuki−Miyaura Cross-Coupling of Sterically Hindered Aryl Chlorides: Synthesis of Di- and Tri-ortho-substituted Biaryls in 2-Propanol at Room Temperature. J Am Chem Soc 2003; 125:16194-5. [PMID: 14692753 DOI: 10.1021/ja038631r] [Citation(s) in RCA: 446] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The catalytic formation of di- and trisubstituted ortho biaryl junctions has been achieved using a palladacylce pre-catalyst bearing a N-heterocyclic carbene ligand. This transformation is performed at room temperature in technical grade 2-propanol.
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Affiliation(s)
- Oscar Navarro
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, USA
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188
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Crudden C, Edwards D. Catalytic Asymmetric Hydroboration: Recent Advances and Applications in Carbon−Carbon Bond‐Forming Reactions. European J Org Chem 2003. [DOI: 10.1002/ejoc.200300433] [Citation(s) in RCA: 443] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Cathleen M. Crudden
- Queen’s University, Department of Chemistry, Kingston, Ontario, Canada K7 L 3N6
| | - David Edwards
- Queen’s University, Department of Chemistry, Kingston, Ontario, Canada K7 L 3N6
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189
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Penhoat M, Levacher V, Dupas G. Novel Extension of Meyers' Methodology: Stereoselective Construction of Axially Chiral 7,5-Fused Bicyclic Lactams. J Org Chem 2003; 68:9517-20. [PMID: 14629186 DOI: 10.1021/jo035195i] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A novel extension of Meyer's lactamization is reported for the preparation of seven-membered ring lactams 1a-d incorporating a biaryl unit. The required keto-esters 2a-c were readily accessible via the Suzuki coupling reaction. A borylation-Suzuki coupling (BSC) sequence was successfully developed for the high-yielding preparation of keto-ester 2d. Cyclization of the resulting keto-esters 2a-d or keto-acids 5a,c,d in the presence of (R)-phenylglycinol afforded the desired lactams 1a-d in high yields (72-93%) and excellent diastereoselectivities (>95%). This methodology provides a facile stereoselective access to new axially chiral bridged biaryls.
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Affiliation(s)
- Maël Penhoat
- Laboratoire de Chimie Organique Fine et Hétérocyclique Associé au CNRS, IRCOF-INSA, Rue Tesnières B.P 08, F-76131 Mont Saint Aignan Cédex, France
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190
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Affiliation(s)
- Roland E Dolle
- Department of Chemistry, Adolor Corporation, 700 Pennsylvania Drive, Exton, PA 19341, USA.
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191
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Abreu AS, Silva NO, Ferreira PM, Queiroz MJR. Palladium-catalyzed borylation and Suzuki coupling (BSC) to obtain β-substituted dehydroamino acid derivatives. Tetrahedron Lett 2003. [DOI: 10.1016/s0040-4039(03)01473-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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192
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Herrbach A, Marinetti A, Baudoin O, Guénard D, Guéritte F. Asymmetric synthesis of an axially chiral antimitotic biaryl via an atropo-enantioselective Suzuki cross-coupling. J Org Chem 2003; 68:4897-905. [PMID: 12790597 DOI: 10.1021/jo034298y] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A catalytic asymmetric synthesis of the axially chiral bridged biaryl (-)-2, a structural analogue of natural (-)-rhazinilam possessing original antimitotic properties, is described. The key step is an intermolecular asymmetric Suzuki coupling, furnishing the nonbridged biaryl (-)-6, precursor of (-)-2, with up to 40% ee using binaphthyl ligand 7a. Various known or new binaphthyl and ferrocenyl phosphines as well as phosphetanes were screened as ligands in this reaction, the conditions of which were optimized. The comparison with another Suzuki coupling system showed that 7a is the most versatile ligand described to date for this type of transformation. This work gives the first application of the asymmetric Suzuki coupling to a biologically relevant target.
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Affiliation(s)
- Audrey Herrbach
- Institut de Chimie des Substances Naturelles, CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette, France
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193
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Ferreira IC, Queiroz MJR, Kirsch G. Tandem palladium-catalyzed borylation and Suzuki coupling (BSC) to thienocarbazole precursors. Tetrahedron Lett 2003. [DOI: 10.1016/s0040-4039(03)00952-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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194
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Bremner JB. Chapter 7 Seven-membered rings. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0959-6380(03)80019-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
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195
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Natural Bridged Biaryls with Axial Chirality and Antimitotic Properties. BIOACTIVE NATURAL PRODUCTS (PART J) 2003. [DOI: 10.1016/s1572-5995(03)80011-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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196
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Baudoin O, Claveau F, Thoret S, Herrbach A, Guénard D, Guéritte F. Synthesis and biological evaluation of A-ring biaryl-carbamate analogues of rhazinilam. Bioorg Med Chem 2002; 10:3395-400. [PMID: 12213452 DOI: 10.1016/s0968-0896(02)00270-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An improvement of the synthesis of biphenyl-carbamate 2a, the most active analogue of rhazinilam 1 so far, was performed using the Pd-catalyzed borylation/Suzuki coupling (BSC) method developed in our laboratories. The preparation of A-ring analogues of 2a bearing electron-withdrawing or donating groups is reported according to this new synthetic scheme. The antitubulin properties as well as the cytotoxicity of these compounds toward human cancer cell lines were evaluated in comparison with rhazinilam and 2a.
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Affiliation(s)
- Olivier Baudoin
- Institut de Chimie des Substances Naturelles, CNRS, avenue de la Terrasse, Gif-sur-Yvette, France.
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197
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Grasa GA, Viciu MS, Huang J, Zhang C, Trudell ML, Nolan SP. Suzuki−Miyaura Cross-Coupling Reactions Mediated by Palladium/Imidazolium Salt Systems. Organometallics 2002. [DOI: 10.1021/om020178p] [Citation(s) in RCA: 301] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gabriela A. Grasa
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148
| | - Mihai S. Viciu
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148
| | - Jinkun Huang
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148
| | - Chunming Zhang
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148
| | - Mark L. Trudell
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148
| | - Steven P. Nolan
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148
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198
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Banwell MG, Smith JA. Exploiting multiple nucleophilic sites on pyrrole for the assembly of polyheterocyclic frameworks: application to a formal total synthesis of (±)-aspidospermidine. ACTA ACUST UNITED AC 2002. [DOI: 10.1039/b208821e] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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