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. 55, No. 2, 2001
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■ Regio- and Diastereoselective Cycloaddition of N-Methyl Nitrones Derived from 3-(Allylamino)propionaldehydes
Masayuki Tanaka, Jun Hikata, Hidetoshi Yamamoto, and Michihiko Noguchi*
*Department of Applied Chemistry, Faculty of Engineering, Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi 755-8611, Japan
Abstract
Regio- and stereochemistry of intramolecular cycloaddition of N-methyl nitrones derived from 3-(allylamino)propionaldehydes was discussed; the methyl substituent at the 3-position in the nitrones (11) provided a highly controlled course of the cycloaddition to give predominantly syn-cis-fused adducts (12), while the reaction of the corresponding 2-methyl nitrone (7a) gave syn-cis- and anti-cis-fused (8a) and syn- and anti-bridged adducts (9a).
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■ Indium-mediated Stereospecific Glycosylation of Alcohols
Bimal K. Banik,* Susanta Samajdar, Indrani Banik, Oliwia Zegrocka, and Frederick F. Becker
*Department of Molecular Pathology, M. D. Anderson Cancer Center, The University of Texas, Box 89, 1515 Holcolmbe Blvd, Houston, TX 77030, U.S.A
Abstract
Indium has been shown to be effective in the stereospecific glycosylation of various alcohols with bromosugars.
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■ A New Method for Synthesizing a Pyrrole Ring and Its Application to the Development of New π-Systems
MinekoTakeda, Shoji Matsumoto, and Katsuyuki Ogura*
*Department of Materials Technology, Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
Abstract
A new type of reaction was developed for the construction of a pyrrole ring. When 1,8-disubstituted 2,7-bis(p-tolylsulfonyl)-1,7-octadiene-3,6-diynes (6) was treated with an aniline derivative (7) in the presence of CuCl (1.6 equiv.) and CuCl2 (0.16 equiv.) in DMF (at 90 °C), one 2-sulfonyl-1-alken-3-yne part of 6 was converted to a 1-arylpyrrole skeleton in a reasonable yield.
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■ Asymmetric Baeyer-Villiger Oxidation of Cyclobutanones Using Diethylzinc/Oxygen/Chiral Amino Alcohols
Toshio Shinohara, Shingo Fujioka, and Hiyoshizo Kotsuki*
*Department of Material Science, Faculty of Science, Kochi University, 2-5-1, Akebono-cho, Kochi 780-8520, Japan
Abstract
A novel method for the asymmetric Baeyer-Villiger oxidation of cyclobutanones using diethylzinc/oxygen/chiral amino alcohols has been developed. The best result was obtained using (1R,2S)-N,N-diethylnorephedrine as the chiral ligand: 3-phenylcyclobutanone was converted into (S)-β-phenyl-γ-butyrolactone with 39% ee and in 75% chemical yield.
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■ Cycloaddition of Synthetic Equivalent of Non-stabilized Aminonitrile Ylides: A New Route to Amino-substituted Δ2-Imidazolines and Δ3-1,2,4-Triazolines
Otohiko Tsuge,* Taizo Hatta, Hideki Tashiro, and Hironori Maeda
*Department of Applied Chemistry, Sojo University, 4-22-1, Ikeda, Kumamoto-shi, 860-0082, Japan
Abstract
The N-unsubstituted nonstabilized azomethine ylides generated from the desilylation of N-[(trimethylsilyl)methyl]iminium triflates undergo successful cycloaddition to strongly polarized sulfonylimines and diethyl azodicarboxylate to produce the corresponding Δ2-imidazolines and Δ3-1,2,4-triazolines together with the initial cycloadducts. The initial cycloadducts are converted to the corresponding aminonitrile ylide cycloadducts. Thus the present process provides a new route to amino-substituted Δ2-imidazolines and Δ3-1,2,4-triazolines that are otherwise relatively inaccessible.
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■ Cycloaddition of New N-Unsubstituted Azomethine Ylides Generated from N-[(Trimethylsilyl)methyl]thiocarbamates, Synthetic Equivalents of Non-stabilized Alkoxy- or Alkylthionitrile Ylides
Otohiko Tsuge,* Taizo Hatta, Masanori Shinozuka, and Hideki Tashiro
*Department of Applied Chemistry, Sojo University, 4-22-1, Ikeda, Kumamoto-shi, 860-0082, Japan
Abstract
The reaction of (trimethylsilyl)methyl isothiocyanate with alcohol in the presence of aluminum alkoxide provides a useful route for the preparation of N-[(trimethylsilyl)methyl]thiocarbamates. The S-methylation of thiocarbamates followed by desilylation generates nonstabilized azomethine ylides having both methylthio and alkoxy groups at the ylide carbon. These azomethine ylides react with electron-deficient carbon-carbon multiples bonds to give formal alkoxynitrile ylide- and/or methylthionitrile ylide-cycloadducts. Thus, the azomethine ylides can be synthetic equivalents of nonstabilized alkoxy- or methylthionitrile ylides that are otherwise relatively inaccessible.
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■ 2-(2-Thienyl)- and 2-Phenylthieno[2,3-b][1,4]thiazines: Synthesis via Suzuki Reaction of the Diphenylphosphates
Thomas Erker* and Elisabeth Krainz
*Institute of Pharmaceutical Chemistry, University of Vienna, Währinger Strasse 10, A-1090 Vienna, Austria
Abstract
Thienothiazinones can be coupled with arylboronic acids using diphenyl phosphates as intermediates and Pd(PPh3)4 as catalyst.
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■ Regioselective Friedel-Crafts Acylation with Unsymmetrically Substituted Furan-dicarboxylic Acid Anhydride and Furan Acid Chloride: Syntheses of 4-Substituted 3-Arylcarbonyl-2-phenylfuran and 3-Substituted 4-Arylcarbonyl-2-phenylfuran
Shrong-Shi Lin, Xiao-Ping Nie, Jun-Hua Yu, and Xiu-Lin Ye*
*Department of Chemistry, Peking University, Beijing 100871, China
Abstract
Friedel-Crafts acylation of aromatic compounds with 2-phenylfuran-3,4-dicarboxylic acid anhydride (4) and 3-methoxycarbonyl-2-phenylfuran-4-carboxylic acid chloride (6) was studied. The reaction with 4, unsymmetrically substituted cyclic anhydrides, afforded 2-phenyl-3-arylcarbonylfuran-4-carboxylic acids (7) in moderate to good yields. Possible mechanism for such regioselective ring opening was also proposed. No interchanged isomeric product was noted for acylation of aromatic compounds with ester acid chloride (6). The synthesis of the precursor of 6, 3-methoxycarbonyl-2-phenylfuran-4-carboxylic acid (5), was achieved by regioselective hydrolysis from dimethyl 2-phenylfuran-3,4-dicarboxylate (2).
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■ New Approach to Synthesis of N-Substituted 9-Amino/Iminoacridines with Important Fluorescence Properties
Pavol Kristian,* Juraj Bernát, Ján Imrich, Erik Sedlák, Juraj Alföldi, and Michal Cornanic
*Department of Organic Chemistry, P. J. Safárik University, Moyzesova 11, SK-04167 Kosice, Slovakia
Abstract
In order to obtain new fluorogens simple versatile methods of synthesis of some O-alkyl [(10-methylacridinium-9-yl)amino]methanethioate trifluoromethanesulfonates, O-alkyl [(10-methyl-l0H-acridin-9-ylidene)amino]methanethioates and O-alkyl [(10-methyl-10H-acridin-9-ylidene)amino]carboxylates were elaborated. The fluorescence properties of compounds under study were discussed.
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■ Alkylation of Some Pyrimidine and Purine Derivatives Using Microwave-assisted Methods
Hortensia Rodríguez, Rolando Pérez, Margarita Suárez, Anabel Lam, Nilda Cabrales, and André Loupy*
*Laboratoire des Réactions Sélectives sur Supports, ICMMO, CNRS UMR 8615, Université de Paris-Sud, Bâtiment 410, 91405 Orsay Cedex, France
Abstract
N-Alkylation of adenine (1), guanine (2) and 6-amino-2-thiouracil (3) with different halides has been carried out using microwave-assisted methods in the presence of small amounts of DMF to improve energy transfer and in the case of 3 by coupling with phase transfer catalysis. The results obtained show high yields and selectivities.
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■ Glycosyl-pyrrolo[2,1-c][1,4]benzodiazepine-5,11-diones. Synthesis, Tensioactivity and Anitbacterial Activity
Driss Bouhlal, Paul Godé, Gérard Goethals, Mohamed Massoui, Pierre Villa, and Patrick Martin*
*Laboratoire de Chimie Organique et Cinétique, Faculté des Sciences, Université de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens Cedex, France
Abstract
Glycosyl-pyrrolo[2,1-c][1,4]benzodiazepin-5,11-diones have been obtained by condensing, at the N-10, different polyhydroxylated groups Su (Su = 6-deoxy-D-glucopyranos-6-yl, 6-deoxy-3-O-R-D-glucopyranos-6-yl (R = n-CnH2n+1; n = 8, 12 and 16), 1-deoxy-D,L-xylit-1-yl and 1-deoxy-D,L-glycer-1-yl). The structural variations of Su allowed us to compare amphiphilic data like water solubility (Sw), critical micelle concentration (CMC) and corresponding surface tension (γ) values. Results of a preliminary antibacterial study are also reported.
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■ Cyclization Reaction of N-Silyl-1-azaallyl Anions with Michael Acceptors as a New Synthetic Method of 2,3,5,6-Tetra- and 2,3,6-Trisubstituted Pyridines
Takeo Konakahara,* Naoki Sugama, Asuka Yamada, Akikazu Kakehi, and Norio Sakai
*Department of Industrial Chemistry, Faculty of Science and Technology, Science University of Tokyo, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
Abstract
Fifteen kinds of 2,3,5,6-tetra- or 2,3,6-trisubstituted pyridines were synthesized from N-silyl-1-azaallyl anions and Michael acceptors in excellent to moderate yields.
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■ Sulfonamidoacetal Cyclization-based Synthesis of a Tetrahydrooxazaphenalenelactone Related to the ABC-Ring System of the Stephaoxocanes
Teodoro S. Kaufman
*Instituto de Química Orgánica de Síntesis-IQUIOS(CONICET-UNR), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, CC 991, Suipacha 570 (S2002LRK), Rosario, Argentina
Abstract
The elaboration of a tetrahydrooxazaphenalenelactone embodying the ABC-ring system of the stephaoxocanes, by means of Jackson’s sulfonamidoacetal cyclization as the isoquinoline ring-forming strategy, is reported.
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■ Scope and Limitations in the Regioselective Synthesis of 1,3,5-Trisubstituted Pyrazoles from β-Amino Enones and Hydrazine Derivatives. 13C-Chemical Shift Prediction Rules for 1,3,5-Trisubstituted Pyrazoles
Angel Alberola, Luis Calvo Bleye, Alfonso González-Ortega,* M. Luisa Sádaba, and M. Carmen Sañudo
*Deparamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, 47005 Valladolid, Spain
Abstract
β-amino enones react with hydrazine derivatives to give regioselectively 1,3,5-trisubstituted pyrazoles. The synthetic method only presents limitations when the β-substituent of the enone and the hydrazine substituent are bulky or possess an electron withdrawing character. Comparison of the 13C-NMR spectra of the seventy pyrazoles allowed us to estimate a 13C-chemical shift prediction rule for 1,3,5-trisubstituted pyrazoles, with deviations of less than ± 1 ppm.
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■ A Three-Step Synthesis of Optically ActiveÅ@5-Halomethyl-2-oxazolidinones; Asymmetric Desymmetrization of Prochiral 1,3-Dihalo-2-propyl Carbamates
Shigeo Sugiyama, Kenji Morishita, and Keitaro Ishii*
*Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan
Abstract
Optically active 5-bromomethyl-2-oxazolidinones (2a and 3a) and 5-Å@chloromethyl-2-oxazolidinones (2b and 3b) were readily prepared from prochiral 1,3-dibromo-2-propanol (7a) and 1,3-dichloro-2-propanol (7b) by a three-step sequence involving formation of carbamates (6a-c) followed by asymmetric desymmetrization (up to 50% de) and debenzylation by anisole-methanesulfonic acid system.
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■ The Action of Maleic Anhydride toward 4-Methylpyrimidine
Ionel I. Mangalagiu,* Geanina C. Mangalagiu, and Magda Ghe. Petrovanu
*Department of Organic Chemistry, Faculty of Chemistry, I“Al. I. Cuza” University of Iasi, B-dul Copou, No. 11, Iasi-6600, Romania
Abstract
A method for obtaining a new class of pyrimidinium ylides (type 3) is presented. Their structures have been proved both by chemical and spectral methods (including two-dimensional experiments: 2D-COSY, 2D-HETCOR and 2D-HETCOR long range). The ability of the ylide to react with activated alkynes and alkenes has been studied. The ylide (3) could act as an initiator in anionic polymerisation leading to oligomers.
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■ A Synthesis of Bipowine and Bipowinone
Somsak Ruchirawat* and Sunthorn Predapitakkun
*Labotratory of Medicinal Chemistry, Chulabhorn Reseach Institute, Vipavadee-Rangsit Highway, Bangkok 10210, Thailand
Abstract
Various oxidizing agents were investigated for the synthesis of bipowine (1) and bipowinone (2), two symmetrical dimeric aporphine alkaloids, from the oxidative coupling of dehydroaporphine (3).
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■ Nitrate Radical Induced Oxidative, Self-terminating Radical Cyclization Cascades: Improvement of Yield Using a Photochemical Radical Source
Lars Lietzau and Uta Wille*
*Institut für Organische Chemie, Universität Kiel, Olshausenstr. 40, D-24098 Kiel, Germany
Abstract
Using the photolysis of cerium ammonium nitrate to generate nitrate radical (NO3·) the alkynyl ether (1) could be cyclized through an oxidative, self-terminating radical cyclization cascade to give the tetrahydrofuran (5) in good yield. This radical source is more favorable than the earlier used anodic oxidation of lithium nitrate, because high local concentrations of oxidants are avoided.
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■ A Convenient Synthesis of 4-Aminoquinazoline Derivatives
Isao Shibuya,* Yasuo Gama, and Masao Shimizu
*National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
Abstract
4-(N,N-Disubstituted amino)-2-substituted quinazoline derivatives (1- 9) were newly synthesized through cyclodesulfurization of N-thiocarbonylarylamines with silver perchlorate in the presence of N,N-disubstituted cyanamides.
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■ Synthesis of Benzo[de]chromene Analogue of Efaroxan
Patrice Mayer,* Sonia Alibert, Pascale Brunel, and Thierry Imbert
*Division de Chimie Médicinale III, Institut de Recherche Pierre Fabre, 17, avenue Jean Moulin, F-81106 Castres Cedex 06, France
Abstract
2-(2-Ethyl-2,3-dihydro-benzo[de]chromen-2-yl)-4,5-dihydro-1H-imidazole (2) was synthesized in seven steps starting from 3-methylanthranilic acid (3). The key intermediate 8-bromomethyl-4-bromonaphthoxybutyrate (8) was obtained starting from 8-methyl-1-naphthol (5b). The target molecule is a benzo[de]chromene analogue of efaroxan (1), a potent and selective antagonist of α2-adrenoceptors.