HETEROCYCLES
An International Journal for Reviews and Communications in Heterocyclic ChemistryWeb Edition ISSN: 1881-0942
Published online by The Japan Institute of Heterocyclic Chemistry
Regular Issue
Vol. 51, No. 9, 1999
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■ Lewis Acid-mediated Ring Expansion Reaction of 2,3-Methanochromanones with Silyl Enol Ethers
Yosiaki Sugita, * Kazuyoshi Kawai, Hiroki Hosoya, and Ichiro Yokoe
*Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japana
Abstract
In the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf), methanochromanones easily reacted with silyl enol ethers to give the [3+2] cycloadducts and the corresponding adducts in good yields.
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■ Synthesis of 3-Alkyl-5,6-diphenylpyrimidine-2,4-diones from N-Carbamoylsulfilimines and Diphenylcyclopropenone
Masahiko Takahashi,* Yuhsuke Kadowaki, Yasuo Uno, and Yoshiharu Nakano
*Department of Materials Sciences, Faculty of Engineering, Ibaraki University, 4-12-1 Nakanarusawamachi, Hitachi, Ibaraki 316-8511, Japan
Abstract
3-Alkyl-5,6-diphenylpyrimidine-2,4-diones (uracil derivatives) have been prepared in moderate to good yields from N-carbamoylsulfihimines and diphenylcyclopropenone in one step. The alkyl group was regioselectively introduced into to the N-3 position of the pyrimidine ring.
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■ Synthetic Studies towards the Synthesis of Western and Eastern Chloropeptin I, II Subunits
Georges Roussi,* Eduardo González Zamora, Annie-Claude Carbonnelle, and René Beugelmans
*Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, Avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France
Abstract
The western subunit (16-membered ring) was synthesized by the intramolecular SNAr reaction while the first 16-membered ring compound was obtained as a model of the eastern subunit via an intramolecular Ni0 mediated coupling reaction.
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■ Asymmetric Synthesis of Octahydro-2H-pyrido[1,2-a]pyrazines
Olivier Froelich, Françoise Cossart, Martine Bonin, Jean-Charles Quirion,* and Henri-Philippe Husson*
*Laboratoire d'Hétérochimie Organique, Associé au C.N.R.S., IRCOF, INSA de Rouen, Place Emile Blondel, P08, 76131 Mont-Saint-Aignan Cedex, France
Abstract
A series of optically pure octahydro-2H-pyrido[1,2-a]pyrazines has been prepared from (-)-2-cyano-6-phenyloxazolopiperidine (4). 2H-Pyrido[1,2-a]pyrazin-3-(4H)-one (7) and octahydro-2H-pyrido[1,2-a]pyrazine (14) were obtained from diamino alcohol (5) by cyclization of bromo- or chloroamides (6) and (10). (4R,9aS)-1,1,4-Triphenyloctahydro-2H-pyrido[1,2-a]pyrazine (16) was synthesized by cyclization of amino alcohol (15c). The formation of cyclic urea (8aS)-diphenyl-3-oxooctahydroimidazo[1,5-a]pyridine (18) was observed during the hydrogenolysis of the corresponding carbamate (17).
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■ Reaction of rel-(4R,5R)-4-Benzoylamino-5-phenyl-3-pyrazolidinone with Aliphatic 1,3-Dicarbonyl Compounds. A ’Ring Switch’ Synthesis of rel-(2R,3R)-3-Phenyl-3-(pyrazolyl-1)alanine Esters
Jurij Svete and Branko Stanovnik*
*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, P.O. Box 537, SLO-1000 Ljubljana, Slovenia
Abstract
rel-(2R,3R)-N-Benzoyl-3-phenyl-3-(pyrazolyl-1)alanine esters (5-8) were prepared by acid-catalysed treatment of rel-(4R,5R)-4-benzoylamino-5-phenyl-3-pyrazolidinone (1) with various aliphatic 1,3-dicarbonyl compounds (2-4).
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■ New 1,3,5-Heterocyclohexanes: Dioxazines, Oxadiazines, Thiadiazines, Oxathiazines and Triazines and Their Amination, Transamination and Disproportionation Reactions
Angelina Flores-Parra* and Sonia A. Sánchez-Ruíz
*Department of Chemistry, Centro de Investigación y de Estudios Avanzados del I.P.N., A.P. 14-740, C.P. 07000 México, D.F., México
Abstract
New 1,3,5-heterocyclohexanes: 5-alkyl-1,3,5-dioxazines (R= iPr, tBu and [R]-α-methylbenzyl), 3,5-di([R]-α-methylbenzyl)-1,3,5-oxadiazine, 3,5-di([R]-α-methylbenzyl)-1,3,5-thiadiazine, 5-isopropyl-1,3,5-oxathiazine, 1-isopropyl-3,5-dimethyl-1,3,5-triazine, 1-tert-butyl-3,5-dimethyl-1,3,5-triazine are reported. Amination and transamination reactions of 1,3,5-heterocyclohexanes were investigated. Equilibria between different heterocycles were found. 13C NMR studies allowed to observe new 1,3,5-heterocycles: 1,3,5-triazines bearing two different alkyl substituents, 3,5-ditert-butyl-1,3,5-thiadiazine, 3-tert-butyl-5-isopropyl-1,3,5-oxadiazine. 1,3,5-heterocyclohexanes present a ring fluxional behavior, the ring inversion energy was calculated for dioxazines, oxadiazine, thiadiazines and triazines.
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■ Synthesis of 3-(4-Aryl-3-cyano-2-methoxypyridin-6-yl)tropolones by the Reactions of 3-Cinnamoyltropolones with Malononitrile
Dao-Lin Wang and Kimiaki Imafuku*
*Department of Chemistry, Faculty of Science, Kumamoto University, Kurokami 2-39-1, Kumamoto 860-8555, Japan
Abstract
3-Cinnamoyltropolones (1a-k) reacted with malononitrile in methanol in the presence of sodium hydroxide or methoxide to give 2-(4-aryl-3-cyano-2-methoxypyridin-6-yl)tropolones (2a-k) via Michael addition and cydization. The reactions in the presence of ethoxide or 1-propoxide afforded the corresponding 2-ethoxy- and 2-(l-propoxy)pyridine derivatives (3a,b), respecvely. 3-(3-Heterocycle-substituted 2-propenoyl)tropolones (6a-d) gave the pyridines (7a-d) having both tropolone and heteocyclic ring.
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■ Pyrrolo[2,3-b][1,4]benzothiazine. A New Ring System from Azidopyrroles
Patrizia Diana, Alessandra Passannanti, Paola Barraja, Antonino Lauria, and Girolamo Cirrincione*
*Instituto Farmacochimico, Università Degli Studi di Palermo, Via Archirafi 32, 90123 Palermo, Italy
Abstract
Nucleophilic substitutions in pyrrole series by uncharged nucleophiles, represented a valuable and versatile method to synthesize different types of key intermediates such as compounds (6), that were used to prepare the corresponding azides (10) which by thermal decomposition afforded the title ring system (11).
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■ The Preparation of 1-Methyl- (and Ethyl)-1,4-dihydro-4-oxo- and 4-thioxo-3-quinolinesulfonamides from 4-Amino-3-quinolinesulfonamides
Leszek Skrzypek
*Department of Organic Chemistry, Sileaian School of Medicine, Jagiellonska Str. 4, 41-200 Sosnowiec, Poland
Abstract
Basic hydrolysis of 1-methyl or 1-ethyl-4-amino-3-aminosulfonylqui- nolinium alkyl sulfates (4) obtained from 4-amino-3-quinolinesulfonamides (2) yields 1-methyl- and 1-ethyl-1,4-dihydro-4-oxo-3-quinolinesulfonamides (5). Salts (4) reacted with sodium hydrosulfide to give sulfur analogs of the compounds (5), i.e., 1-alkyl-1,4-dihydro-4-thioxo-3-quinolinesulfonamides (7).
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■ Novel Dipolar and Tripolar Betaines: Synthesis, Ring-Cleavage, Spectroscopic Features, and X-Ray Analysis of a Positively Charged Pyrimidin-4-olate
Andreas Schmidt* and Martin Nieger
*Ernst-Moritz-Arndt-Universität Greifswald, Institut für Chemie und Biochemie, Soldmannstrasse 16, D-17487 Greifswald, Germany
Abstract
Reaction of tetrachioropyrimidine (1) with pyridine resulted in the formation of a heteroaromatic tripole, the 2,6-bispyridiniopyrimidin-4-olate chloride (3), the structure of which was established by X-Ray crystallography. Amberlite® IRA-400 in its hydroxy form converted 3 into the corresponding stable hydroxide (4), which undergoes ring-cleavage on titration with sodium hydroxide to pH 9. Thus, the 5-aminopenta-2,4-dienal appended mesomeric betaine (5) formed.
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■ Synthesis of 6-Substituted 5,6,7,12-Tetrahydrobenzo[4,5]cyclohept[b]indol-12-one Derivatives
Abderrahim Mouaddib, Benoît Joseph, Aissa Hasnaoui, Jean-Yves Mérour,* and Stéphane Léonce
*Institut de Chimie Organique et Analytique, UMR CNRS 6005, Université d'Orléans, BP 6759, Rue de Chartres, 45067 Orléans Cédex 2, France
Abstract
The synthesis of 6-substituted 5,6,7,12-dihydrobenzo[4,5]cyclohept[b]indole derivatives, through a regioselective alkylation of 1 in position-6, is reported. The antiproliferative activity of 18 was evaluated.
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■ Synthesis and Reactivity of Some Mannich Bases. VII. Synthesis of 3-(2-Dialkylaminoethyl)-1,2-benzisoxazoles
Eugenia Comanita, Irina Popovici, Gheorghe Roman, Gilles Robertson, and Bogdan Comanita*
*National Research Council of Canada, Institute for Chemical Process and Environmental Technology, Montreal Road Compus, Ottawa, Ontario, K1A 0R6, Canada
Abstract
3-(2-Dialkylaminoethyl)-1,2-benzisoxazoles (2) are accessible by direct cyclization of the corresponding Mannich bases oxime acetates (11) in refluxing benzene in the presence of anhydrous potassium carbonate. The previously known methods for ring closure to 1,2-benzisoxazole were ineffective for this class of pharmacologically relevant compounds.
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■ 1,3-Dipolar Cycloadditions of Photoinduced Carbonyl Ylides. Part 3: Photoreactions of α,β-Unsaturated γ,δ-Epoxy Dinitrile, α-Cyano Ester, and Diester with Various Dipolarophiles
Masashi Kotera, Keitaro Ishii,* Masaru Hiraga, and Masanori Sakamoto
*Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan
Abstract
Photoinduced carbonyl ylide (A) from α,β-unsaturated γ,δ-epoxy dinitrile (1) undergoes 1,3-dipolar cycloaddition with enol ethers, leading to tetrahydrofuran system with high regioselectivity in moderate yield. However, The cycloadditions of A with nonactivated and electron-deficient olefins and with C=N containing dipolarophiles gave the corresponding adducts slightly. The reactivity for the cy-cloaddition of α-cyano ester (8) and diester (9) with ethyl vinyl ether decreases.
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■ Chemo- and Regioselective Nucleophilic Reactions of (Bromomethyl)methylmaleic Anhydride: Synthesis of α-Quinoxalinyl- and α-Benzothiazinylacrylic Acids
Anil M. Deshpande, Arvind A. Natu, and Narshinha P. Argade*
*Division of Organic Chemistry (Synthesis), National Chemical Laboratory, Pune 411 008, India
Abstract
The (bromomethyl)methylmaleic anhydride (2) on reaction with o-phenylenediamine and o-aminothiophenol underwent chemo- and regioselective ring opening followed by intramolecular Michael type addition and 1,4-elimination reactions to furnish kinetically controlled products α-quinoxalinylacrylic acid (5) and α-benzothiazinylacrylic acid (6) in good yields.
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■ Synthesis of 2-Hydroxypyrido[2,3-a]-carbazoles and 2-Hydroxypyrimido[4,5-a]carbazoles from 1-Hydroxycarbazoles
Kandasamy Shanmugasundaram and Karnam J. Rajendra Prasad*
*Department of Chemistry, Bharathiar University, Coimbatore - 641 046, Tamil Nadu, India
Abstract
Gattermann reaction on substituted 1-hydroxycarbazoles (4a-d) afforded substituted 1-hydroxycarbazole-2-carbaldehydes (5a-d) from which synthesis of either 2-hydroxypyrido[2,3-a]carbazoles (7a-d) via Perkin reaction or 2-hydroxypyriinido[4,5-a]carbazoles (8a-d) via condensation with urea could be achieved.
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■ Triazolo[4,5-f]quinolines Derived from 5-Amino-(1H- and 2-methyl-2H)-benzotriazoles with β-Diketones and 3-Buten-2-one
Paolo Sanna,* Antonio Carta, and Giuseppe Paglietti
*Dipartimento Farmaco Chimico Tossicologico, Universita di Sassari, Via Muroni 23/a, 07100 Sassari, Italy
Abstract
5-Aminobenzotriazole and its derivatives are good substrates for reactions with β-diketones and 3-buten-2-one to produce angular triazolo[4,5-f]quinolines. Interesting isomeric compounds were found in the case of reaction with non-symmetrical diketones, whereas an unusual cyclization takes place when 2-acetylcyclopentanone was used.
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■ New Coumarins from Mesua racemosa: Isolation and Synthesis
Cécile Morel, Caroline Dartiguelongue, Thierry Youhana, Jean-Michel Oger, Denis Séraphin, Olivier Duval, Pascal Richomme,* and Jean Bruneton
*SONAS, UFR de Médecine et Pharmacie, Ingénierie de la santé, 16 Bd. Daviers, 49100 Angers, France
Abstract
The isolation and identification of four new coumarins (racemosone, furanoracemosone, mammea A/BC, isoracemosol) isolated from the leaves of Mesua racemosa are reported. Their structures were established by means of spectroscopic studies and confirmed by synthesis.
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■ Access to Quinazolines from 2-Nitrobenzaldehyde and Arylamines
Jaime A. Valderrama,* Hernán Pessoa-Mahana, Gabriela Sarras, and Ricardo Tapia
*Facultad de Química, Pontificia Universidad Católica de Chile, Casilla 306, Correo 22, Santiago, Chile
Abstract
A synthesis of N-(2-nitrobenzyl) acetanilide (5) and (11) from 2-nitrobenzaldehyde and aromatic amines is reported. The reaction of amides (5) and (11) with iron in acetic acid-ethanol-water provided the corresponding 3-phenyl-1,2,3,4-tetrahydroquinazolines (7) and (12). Reductive cyclization of 1-acetyl-2-(2-nitrophenyl)-benzimidazol (16) to benzimidazo[1,2-c]quinazoline (19) and benzimidazol (20) is described.
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■ Syntheses and Properties of Chiral Tricyclic Compounds Bridged by Cystine Units
Kazuaki Ito,* Yoshihiro Ohba, and Tyo Sone
*Department of Materials Science and Engineering, Faculty of Engineering, Yamagata University, 4-3-16 Jyonan, Yonezawa 992-8510, Japan
Abstract
Novel chiral tricyclic compounds were prepared from the reactions of the cystine dimethyl ester and 4-substituted 2,6-bis(chloromethyl)phenol derivatives. The 1H-NMR and CD spectra showed the existence of chiral twisting of the cyclophane unit, which was induced by the chirality of the cystine moiety.
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■ Synthesis of 1H-1,2,4-Triazolo[5,1-a]isoindoles by Intramolecular Condensation of 4-Substituted 1,2,4-Triazol-1-ium 4-Substituted Benzoyl 2,4,6-Trinitrophenylmethylides
Georgiana G. Surpateanu,* Gérard Vergoten, Abdelaziz Elass, and Gheorghe Surpateanu
*CRESIMM Centre de Recherche et Etudes en Simulation et Modélisation Molécularies, UMR 111 CNRS, Université des Sciences et Technologies de Lille, Bat. C8, 59655 Villeneuve D' Ascq Cedex, France
Abstract
The reaction of the 4-substituted 1,2,4-triazol-1-ium 4-substituted benzoyl 2,4,6-trinitrophenylmethylides (5) with piperidine gave the 1H-1,2,4-triazolo[5,1-a]isoindoles (7) by a cyclization and then elimination of nitrous acid.
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■ Sciaferine and N-Formylanolobine, Two New Aporphine Alkaloids from the Neutral Fraction of Sciadotenia toxifera
Alan J. Freyer,* Lew B. Killmer, Mary D. Menachery, and Alan J. Kanouff
*Analytical Chemistry, SmithKline Beecham Synthetic Chemistry, 709 Swedeland Rd., P.O.Box 1539, Kinf of Prussia, PA 19406-0939, U.S.A.
Abstract
The structures of sciaferine (1), a new oxoaporphine alkaloid, and N-formylanolobine (2), both isolated from the neutral fraction of Sciadotenia toxifera, were determined by spectral methods.
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■ Effect of C-1, C-2, and C-3 Substituents on the Conformational Equilibrium of Indolo[2,3-a]quinolizidines
Mauri Lounasmaa* and Pirjo Hanhinen
*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, P.O. Box 6100, FIN-02150 HUT Espoo, Finland
Abstract
Conformational behavior of indolo[2,3-a] quinolizidines possessing alkyl (or similar) and/or methoxycarbonyl substituents at C-1, C-2, and/or C-3 positions has been examined. Effects influencing the conforrnational equilibrium are discussed. A method of predicting the predominant conformation, usually with good accuracy, is described. Combined with 13C NMR data the method can be used for stereochemical conclusions.
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■ Systematic Tables of Mono- and Poly-N-methylated Adenines: Acid Dissociation Constants and UV and NMR Spectral Data
Tozo Fujii* and Taisuke Itaya
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Available data regarding acid dissociation constants and UV, 1H NMR, and 13C NMR spectra of all the five positional iso-mers (2-6) of NX-methyladenine, 10 known isomers (7-16) of Nx,Ny-dimethyladenine, nine known isomers (17-25) of Nx,Ny,Nz-trimethyladenine, and five known isomers (26-30) of tetra-N-methylated adenine are tabulated for convenience of ready comparison, with 117 reference citations.