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. 38, No. 3, 1994
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■ Synthesis of Adenine 7-Oxide from Adenine: Utilization of a Benzyl Group as a Control Synthon at the 3-Position
Tozo Fujii,* Kazuo Ogawa, Tohru Saito, Keiko Kobayashi, and Taisuke Itaya
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
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■ A Facile Synthesis of New Prostaglandin Analogues by Utilizing the Characteristics of the 1,2,4-Triazole Moiety
Shigeki Sano, Michiko Tanba, and Yoshimitsu Nagao*
*Faculty of Pharmaceutical Sciences, University of Tokushima, Sho-machi, Tokushima 770-8505, Japan
Abstract
Concise syntheses of some new prostaglandin analogues bearing the 1,5-disubstituted 1,2,4-triazole moiety were achieved by utilizing the characteristics of N2-substituted 3-nitro-1,2,4-triazole and/or N1-substituted 1,2,4-triazole derivatives.
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■ Absolute Structure of Bruceine H by X-Ray Analysis
Yaeko Konda,* Tomomitsu Sasaki, Nobuyuki Funato, Hiroaki Takayanagi, Lijun Wu, Xian Li, Masayuki Onda, and Yoshihiro Harigaya
*School of Pharmaceutical Sciences, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
The absolute configuration of bruceine H was determined to be 1S, 5S, 7R, 8R, 9R, 10S, 11R, 12S, 13R, 14R, 15R by means of X-ray analysis of 15-O-acetylbruceine H 22-p-bromobenzoate.
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■ Synthesis and Molecular Structure of 3,4,13,14-tetraselenatricyclo[14.4.0.06,11]icosa-1(16),6,8,10,17,19-hexaene
Satoshi Ogawa, Sachiko Ohara, Yasushi Kawai, and Ryu Sato*
*Department of Applied Chemistry, and Molecular Science Faculty of Engineering, Iwate University, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
Abstract
A new selenium containing macrocyclic compound, 3,4,13,14-tetraselenatricyclo[14.4.0.06,11]icosa-1(16),6,8,10,17,19-hexaene (3), was prepared by oxidation of 1,2-bis(selenocyanatomethyl)benzene (2) in a moderate yield. The structure of compound (3) was determined by an X-ray crystallographic analysis and the activation parameters for the conformational changes of 3 in solution were calculated by DNMR experiments.
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■ Synthesis of Five-membered Heteroarylmethyl p-Tolylsulfones from Heteroarenemethanols under Acidic Conditions: Scope and Limitations
Luis Castedo, José Delamano, Carmen López, María Belén López, and Gabriel Tojo*
*Departamento de Química Orgánica , Facultad de Farmacia, Universidad de Santiago de Compostela, E-15706, Santiago de Compostela, Spain
Abstract
It is shown that the successful conversion of five-membered heteroarenemethanols into the corresponding heteroarylmethyl p-tolylsulfones by treatment with sodium p-toluenesulfinate under acidic conditions depends on the stability of the intermediate heteroarylmethyl carbocations.
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■ Nitroimidazoles XI. Syntheses of Substituted (1-Methyl-5-nitro-2-imidazolyl)pyrazoles
Rahim Karimi-Khoozani, Alireza Ghanbarpour,* and Abbas Shafiee
*Department of Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
Abstract
The β-diketone derivatives of nitroimidazole were synthesized from the reaction of magnesium salt of β-keto acids (2) with imidazolide (3). The β-keto acids (1) were obtained from the hydrolysis of β-keto esters (5) or the reaction of magnesium methylcarbonate with the ketone (6). The reaction of β-diketones (4) with hydrazine afforded the pyrazoles (7), which were converted to N-methylpyrazoles (8) and (9). The latters could also be obtained from the reaction of β-diketones (4) with methylhydrazine.
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■ Indoles XI. Syntheses and Stereochemistry of 5,6,7,8,13,13b-Hexahydrobenz[a]indolo[2,3-h]quinolizines and of 5,6,7,8,13,13b-Hexahydro-14H-bisindolo[3,2-a][2,3-h]quinolizine
Jochen Lehmann,* Martin Nieger, and Thomas Witt
*Institute of Pharmacy, University of Bonn, An der Immenburg 4, D-53121 Bonn, Germany
Abstract
A new and efficient synthesis of substituted 5,6,7,8,13,13b-hexahydrobenz[a]indolo[2,3-h]quinolizines (5b,d) via lactamisation of dihydropyrano[3,4-b]indol-1-one (3), cyclisation with phosphorus oxychloride and reduction with sodium borohydride is described. The unsubstituted 5,6,7,8,13,13b-hexahydro[a]benz[2,3-h]quinolizine (5) is prepared by analogy starting with the lactamisation of isochromanone with tryptamine. The unsubstituted 5,6,7,8,13,13b-hexahydro-14H-bisindolo[3,2-a][2,3-h]quinolizine (9) is synthesized by lactamisation of 3 with tryptamine, cyclisation and again reduction of the intermediate immonium salt. The stereochemistry of the unsubstituted quinolizine derivatives is investigated by 1H-, 13C-nmr-, NOE spectroscopy and by X-ray analysis.
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■ Synthesis of the Mutagenic 2-Amino-1,6-dimethylimidazo[4,5-b]pyridine (1,6-DMIP) and Five of Its Isomers
Stefan Lindström, Tania Ahmad, and Spiros Grivas*
*Department of Chemistry, Swedish University of Agricultural Sciences, P.O.Box 7015, SE-750 07 Uppsala, Sweden
Abstract
Synthetic routes to 2-amino-1,6-dimethylimidazo[4,5-b]pyridine and its 1,5-, 1,7-, 3,5-, 3,6- and 3,7-dimethyl isomers from methyl derivatives of 3-hydroxy- or 2-aminopyridine and 2-chloronicotinic acid are described.
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■ Synthesis of Heterocyclic Compounds by the Skraup Reaction of Amino-9H-xanthen-9-ones
Hidetoshi Fujiwara* and Ichizo Okabayashi
*Niigata College of Pharmacy, 5-13-2 Kamishin’ei-cho, Niigata 950-2081, Japan
Abstract
The Skraup reaction of amino-9H-xanthen-9-ones was conducted in the presence of glycerol, fuming sulfuric acid, nitrobenzene, iron (II) sulfate and boric acid. 1-Amino-9H-xanthen-9-one gave 12H-[1]benzopyrano[2,3-h]quinolin-12-one. 2- and 3-amino-9H-xanthen-9-ones gave angular-type products, 12H-[1]benzopyrano[3,2-f]quinolin-12-one and 7H-[1]benzopyrano[3,2-g]quinolin-7-one respectively, without linear-type products. 4-Amino-9H-xanthen-9-one gave 7H-[1]benzopyrano[3,2-h]quinolin-7-one.
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■ Reactivity of Phenyllithium toward Bridgehead Nitrogen Heterocycles
Alain Gueiffier,* Henri Viols, Yves Blache, Olivier Chavignon, Jean Claude Teulade, André Aumelas, and Jean-Pierre Chapat
*Laboratoire de Chimie Organique Pharmaceutique, URA-CNRS 1111, 15 Avenue Charles Flahault, 34060 Montpellier, France
Abstract
The reactivity of phenyllithium toward some bridgehead nitrogen heterocycles was investigated. Imidazo[1,2-a]pyridine gave the substitution, while other series gave addition reactions. In addition, the ring opening derivative was obtained in imidazo[1,2-c]quinazoline series.
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■ The Chemistry and Structure of Some Eudesmane Sesquiterpenoid Bicyclic Orthoesters. Implications for the Hydrolyses of β-Glycosides
Vernon G. S. Box, James V. Bardouille, Wilfred R. Chan, Joan M. Sterling, and David R. Taylor
*Department of Chemistry, City College of the City University of New York, New York,NY 10031, USA
Abstract
The formation of oxonium ions during the acid catalyzed reactions of the tricyclic eudesmanoid orthoesters (3) and (4) is greatly influenced by the overall structural features of the parent molecules. The structures of the reaction products, and molecular modeling of the possible oxonium ions, confirm that the most stable oxonium ion is the most important intermediate. These findings are critical to understanding the hydrolyses of β-glycosides.
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■ 1H-Indazoles a Synthetic Auxiliaries for the Synthesis of Secondary Aromatic Amines
Raffaele Saladino, Claudia Crestini,* and Rosario Nicoletti*
*Dipartrimento di Chimica, Instituto di Farmacologia Medica, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, 00185 Roma, Italy
Abstract
Methodology of alkylation of aromatic amines using 1H-indazoles as synthetic auxiliaries is reported.
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■ A Novel Synthesis of 2,4,5-Triarylimidazoles
Jerome F. Hayes,* Michael B. Mitchell, and Christopher Wicks
*SmithKline Beecham Pharmacuticals, Old Powder Mills, Nr Leigh, Tonbridge, Kent, TN11 9AN, U.K.
Abstract
Aryl cyanides were reacted with a, a-dilithioarylnitromethanes to form 2,4,5-triarylimidazoles in good yield. An unusual cyclisation - elimination mechanism is proposed for this reaction.
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■ One-Pot Synthesis of New 1,3-Imidazolidines Possessing Three Aryl Groups via a 1,3-Dipolar Cycloaddition Reaction
Yoshimitsu Nagao,* Kweon Kim, Yoichi Komaki, Shigeki Sano, Masaru Kihara, and Motoo Shiro
*Faculty of Pharmaceutical Sciences, University of Tokushima, Sho-machi, Tokushima 770-8505, Japan
Abstract
Tri-aryl-substituted imidazolidines (3) were readily synthesized by heating a mixture of arylaldehyde (7), diethyl ketomalonate (8), and benzyl(or substituted benzyl)amine (6) in benzene in the presence of a catalytic amount of p-toluene-sulfonic acid.
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■ Synthesis of Octahydro-2,5-bis(nitroimino)imidazo[4,5-d]imidazole
Michael Kony* and Ian J. Dagley
*DSTO, Materials Research Laboratory(MRL), P.O.Box 50 Melbourne, Victoria 3032, Australia
Abstract
Improved reaction conditions for the preparation of octahydro-5-imino-2-(nitroimino)imidazo[4,5-d]imidazole (3) from 4,5-dihydroxy-2-nitroiminoimidazolidine (2) and guanidine hydrochloride are described. Treatment of the hydrochloride salt of 3 with nitric acid at low temperature generates the nitrate salt of 3 and not octahydro-2,5-bis(nitroimino)imidazo[4,5-d]imidazole (1a) as previously reported. The bis(nitroimino) compound (1a) was obtained by slow addition of nitric acid to a mixture of the monohydrochloride salt of the bicyclic guanidine (3) and acetic anhydride.
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■ The N-Boc Group as an Activator for the α-Lithiation of Carbamates: Synthesis of 11-Substituted Dibenzoxazepines
Timothy J. Hagen,* Michael F. Rafferty, Joe T. Collins, Danny J. Garland, James J. Li, Monica B. Norton, David B. Reitz, Sofya Tsymbalov, Barnett S. Pitzele, and E. Ann Hallinan
*Department of Chemistry, G. D. Searle & Company, 4901 Searle ParkwaySkokie, Illinois 60077, U.S.A.
Abstract
A series of 11-substituted dibenzoxazepines was prepared via α-lithiation utilizing the N-Boc group as an activator. The N-Boc group directs metalation of 5 by n-BuLi to the benzylic C-11 carbon. For 6 which contains 1,3 interrelated directed metalation groups, metalation with n-BuLi occurs at both the 11- and 9-positions. The regioselectivity for the lithiation of 6 can be increased to a ratio of 97:3, by employing LDA as the base, thus providing a convenient and general route to 11-substituted 8-chlorodibenzoxazepines. By the proper choice of the base, the regioselectivity of lithiation-substitution reactions in the pharmaceutically important heteroaromatic ring systems (5) and (6) can be controlled. The N-Boc group can be readily removed with mild acid treatment.
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■ Condensation Reactions of a Nitrodienamine with Indoles in Trifluoroacetic Acid
Naoki Takeuchi,* Mitsuharu Tanabe, Masanori Hagiwara, Kaori Goto, Takeshi Koike, and Seisho Tobinaga
*Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan
Abstract
Treatment of a nitrodienamine (1) with Indoles in trifluoroacetic acid gave condensation products.
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■ Participation of Superjacent and Subjacent Orbitals for the Cycloaddition Reaction of 2H-4,9-Methanocycloundeca[b]furan-2-one with Electron-Deficient Dienophiles
Hiroki Tomioka and Makoto Nitta*
*Department of Chemistry, School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan
Abstract
Cycloaddition reactions of 2H-4,9-methanocycloundeca[b]furan-2-one with dimethyl acetylenedicarboxylate (DMAD) and 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) were studied. The former reaction underwent a [12+2] cycloaddition, but the latter, only a [4+2] and a plausible [12+2] cycloadditions. The similar reaction of 2H-cyclohepta[b]furan-2-one with DMAD underwent a [4+2] and an [8+2] cycloaddition in a ratio of 8:1, while that with PTAD, only [4+2] cycloaddition. The periselectivity of the reactions was discussed on the basis of the MNDO calculations.
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■ Fused Furan Construction via an Intramolecular [3+2] Cycloaddition Reaction: Syntheses of 4H-Cyclohepta- and 4H-Cyclopenta[b]furans
Kozo Shishido,* Koji Umimoto, and Masayuki Shibuya
*Institute for Medicinal Resources, University of Tokushima, 1-78 Sho-machi, Tokushima 770-8505, Japan
Abstract
General and efficient syntheses of 4H-cyclohepta- and 4H-cyclopenta[b]furans (4 and 5) have been accomplished employing the intramolecular [3+2] dipolar cycloaddition based fused furan construction strategy. Treatment of the oximes (20 and 29), readily prepared from the carboxylic acid (7 and 23) via a conventional sequence of reactions, with aqueous sodium hypochlorite produced excellent yields of the isoxazolines (21 and 30), which, after alkaline hydrolysis or desilylation, were exposed to the conditions of reductive hydrolysis followed by acid-catalyzed cyclization to give the corresponding fused furans (4 and 5) in good overall yields.
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■ Synthesis of 6-Methoxy-5,8-quinolinediones and 8-Methoxy-5,6-quinolinediones Using Oxidative Demethylation with Cerium (IV) Ammonium Nitrate
Yoshiyasu Kitahara, Yasuo Nagaoka, Tamaki Matsumura, and Akinori Kubo*
*Meiji College of Pharmacy, 1-35-23 Nozawa, Setagaya-ku, Tokyo 154 Japan
Abstract
6-Methoxy-5,8-quinolinediones (14-19) and 8-methoxy-5,6-quinolinediones (20-25) were synthesized by oxidative demethylation of the corresponding 5,6,8-trimethoxyquinolines (5, 7-9, 12, 13) with cerium (IV) ammonium nitrate.