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. 24, No. 2, 1986
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■ The Enantiomerically Pure Bicyclic β-Lactams Derived from Sugars
Marek Chmielewski,* Zbigniew Kaluza, Czeslaw Belzecki, Piotr Salanski, and Janusz Jurczak
*Institute of Organic Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, P.O.Box 58, PL-01-224 Warszawa 42, Poland
Abstract
Trichloroacetyl isocyanate reacts with glycals 2 and 3 under 10 kbar pressure to give (4+2) adduct 7 or 16, β-lactams 8 and 9 or 17 and 18, respectively. Treatment of the post-reaction mixtures with Florisil enabled to obtain the N-unsubstituted β-lactam 10 in case of products derived from 2, and 19 in case of those derived from 3.
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■ Synthesis of 6-Sulfonylmethylene, 6-Sulfinylmethylene- and Spiropyrazoline-penicillanic Acids
Dieter Häbich* and Karl Metzger
*CWL-Pharma, Bayer AG, Postfach 10 17 09, 5600 Wuppertal-1, Germany
Abstract
The synthesis of the title compounds 1, analogs of 6-acetylmethylenepenicillanic acid, and their products of diazomethane addition 2 are described. Their β-lactamase inhibiting activity is briefly discussed.
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■ Intramorecular Cycloadditions with Isobenzofurans I
Willy Friedrichsen,* B. -Michael König, Knut Hildebrandt, and Tony Debaerdemaeker
*Institut für Organische Chemie, Olshausenstrasse, Universität Kiel, 40, D-24098 Kiel, Germany
Abstract
Intramolecular Diels-Alder reactions with isobenzofurans (5, 12) offer an attractive route for the preparation of polycyclic systems (6, 13).
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■ Regioselective Alkylation of 3-Substituted 3-Sulfolenes
Hiroaki Takayama,* Hiromasa Suzuki, Takashi Nomoto, and Sachiko Yamada
*Faculty of Pharmaceutical Sciences, Teikyo University, 1091-1 Suarashi, Sagamiko-machi, Tsukui-gun, Kanagawa 199-0195, Japan
Abstract
Remarkable directing effect of the substituent on the double bond of 3-sulfolene was found in the reaction with alkyl iodides under basic conditions; electron donating groups effect selective substitution at the 2-position while electron withdrawing groups effect exclusive substitution at the 5-position.
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■ 1,3-Diphenylthieno[2,3-c]furan. A New Heterocyclic System
Willy Friedrichsen* and Axel Schöning
*Institut für Organische Chemie, Universität Kiel, Olshausenstrasse. 40, D-24098 Kiel, Germany
Abstract
The synthesis of 1, 3-diphenylthieno[2,3-c]furan (7) is described.
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■ Synthesis of dl-Vermiculine via Control of Olefin Formation
Takeshi Wakamatsu,* Satoshi Yamada, and Yoshio Ban
*Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812, Japan
Abstract
The Synthesis of the macrodiolide antibiotic vermiculine 1 has been achieved starting from the enediol(trimethylsilyl) enol ether via the macrocyclization of hydroxycarboxylic acids followed by the formation of the requisite trans double bonds.
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■ A New Synthetic Route for 3,4-Disubstituted Tetrahydrothiophenes and a New Fragmentation of Their Ring System
Masahiro Aono, Yoshiyasu Terao, and Kazuo Achiwa*
*Schol of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
Abstract
Desilylation of 2-trimethylsilyl-3,4-disubstituted tetrahydrothiophenes provided a new method for synthesis of title compounds and a new fragmentation reaction of tetrahydrothiophene ring.
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■ Synthesis and Absolute Configuration of the Alangium vitiense Alkaloid (—)-9-Demethyltubulosine
Tozo Fujii,* Masashi Ohba, Hiroshi Hatakeyama, Chiristiane Kan-Fan, and Henri-Phillipe Husson
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
(-)-9-Demethyltubulosine [(-)-I] has been synthesized from the tricyclic amino acid (-)-IV through the intermediates (-)-V, (+)-VI, and (+)-VII. The identity of the synthetic (-)-I with a C28H35N3O3 base, isolated from Alangium vitiense, unequivocally established the structure and absolute stereochemistry of this alkaloid.
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■ Conformational Effects in 1,2-Dithietane, 1,2-Dithiete, 1,3-Dithiole, 2,3-Dihydro-1,4-dithiin and 1,4-Dithiin Radical Cations
Glen A. Russell* and Wing Cheung Law
*Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, U.S.A.
Abstract
1,2-Dithietane radical cations exist in a nonplanar conformation. With trans-3,4-dimethyl substituents, the barrier to ring flip is >5 kcal/mol. Cyclohexene derivatives 7-10 possess a measurable barrier to ring flip. However, the radical cations 11-16 have a much lower barrier and only conformationally time-averaged ESR spectra are observed at -90°C. The 2,3-dihydro-1,4-dithiin ring of 11 or 19 is conformationally mobile but is locked in a half-chair conformation in 12 and 13.
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■ Synthesis of Rosethiophene, a New Flavour Compound
Zeinhom Mostafa Ismail and H. Martin R. Hoffmann*
*Institut fur Organische Chemie, Universität Hannover, Schneiderberg 1 B, D-30167 Hannover, Germany
Abstract
Rosethiophene[3-methyl-2-(3-methyl-2-butenyl)thiophenel (2b) has heen prepared by two routes and converted into the homogeraniol precursor (8).
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■ A New synthesis of 2-Oxathiolone
Pen-Chung Wang*
*Designed Latexes and Resins Research, Michigan Division, 1604 Building, The Dow Chemical Company, Midland, MI 48640, U.S.A.
Abstract
A convenient synthesis of 2-oxathiolone starting from ethylene monothiocarbonate is described.
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■ 2D NMR Study of Ajmaline
Ari M. P. Koskinen and Mauri Lounasmaa*
*Department of Chemistry, Technical University of Helsinki, P.O. Box 6100, FIN-02150 HUT Espoo, Finland
Abstract
A high field 2D NMR study of ajmaline 1 is presented, settling the discrepancy existing in the interpretation of the earlier results.
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■ A New Product from the Decomposition of 2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), a Hydeoxamic Acid from Cereals
Héctor R. Bravo and Hermann M. Niemeyer*
*Departamento de Química, Facultad de Ciencias, Unversidad de Chile, Casilla 653, Santiago, Chile
Abstract
A new product, identified as 3,4-dihydroxy-7-methoxy-1,4-benzoxarin-2-one (5) was isolated in 10% yield from the decomposition of the title compound in dioxane. A mechanism for its formation is discussed.
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■ Nitrogen Nuclear Magnetic Resonance Spectroscopy of Pyridinium Dicyanomethylids
Kiyoshi Matsumoto,* Takane Uchida, Yukio Ikemi, Hideo Fujita, Kuniyo Aoyama, and Momoyo Asahi
*Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-Nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan
Abstract
The 14N and 15N chemical shifts of ylidic nitrogen of substituted pyridinium dicyanomethylids and related compounds have been measured. A linear correlation is obtained between the 13C-SCS and the 15N-SCS of the 4-substituted pyridinium dicyanomethylids. A comparison and/or correlation is made of these values with those of the related molecules such as pyridines and pyridine N-oxides and also by using several different scales of substituent parameters such as σ*, (σI, σR°), and (i, σR+, σR-).
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■ Racemic and Chiral Syntheses of the Alangium Alkaloid Alancine
Tozo Fujii,* Masashi Ohba, Asako Yonezawa, Jun Sakaguchi, Sunil K. Chattopadhyay, David J. Slatkin, Paul L. Schiff, Jr., and Anli B. Ray
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
(±)-Alancine [(±)-I] has been synthesized in good yield from the tricyclic amino acid (±)-V by catalytic hydrogenolysis. Treatment of (±)-I with aqueous HCl gave the hydrochloride salt (±)-I·HCl. A parallel synthesis starting with (-)-V produced (-) -alancine [(-)-I] as well as its hydrochloride (-) -I·HCl in good yields. The synthetic (-)-I·HCl was found to be identical with a sample isolated from Alangium lamarckii Thw.
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■ Nitriles in Heterocyclic Synthesis: Novel Synthesis of Pyrido[2,1-b]benzothiazoles, Pyrimido[6,1-b]benzothiazoles and Pyrazolo[4,3-c]pyridazine Derivatives
Galal Eldin Hamza Elgemeie* and Fatma Abd El Maksoud Abd El Aal
*Chemistry Department, Faculty of Science, Minia University, Minia, Egypt
Abstract
Novel synthesis of pyrido[2,1-b]benzothiazole, pyrimido[6,1-b]benzothiazole and pyrazolo[4,3-c]pyridazine derivatives utilizing 2-cyanomethylbenzothiazole as starting component is reported.
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■ A Theoretical Study of 2- and 3-Arylbenzo[b]thiophenes. Evidence of an Intramolecular Charge Transfer State in 3-α-Naphthybenzo[b]thiophene
Cyril Párkányi,* Annick Brehon, Axel Couture, Alain Lablache-Combier, and Alain Pollet
*Department of Chemistry, The University of Texas at El Paso, El Paso, Texas79968-0513, U.S.A.
Abstract
PPP (LCI-SCF-MO] calculations were used to study the models of benzo[b]thiophene (1), 2-phenylbenzo[b]thiophene (2), 3-phenylbenzo[b]thiophene (3), 2-α-naphthylbenzo[b]thiophene (4), and 3-α-naphthylbenzo[b]thiophene (5). The results of the calculations were used to interpret the electronic absorption and fluorescence spectra of these compounds, to discuss their ground-and excited-state geometry, and to provide support for the existence of an intramolecular charge transfer state in 5, with a geometry different from that of the ground state.
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■ A Side Reaction in the Synthesis of 2-Ethynylthiophene from 2-Thiophenecarboxaldehyde by the Corey Procedure and an Inproved Synthesis of 2,2’:5’,2’’-Terthiophene
Daniel M. Perrine and Jacques Kagan*
*Department of Chemistry, University of Illinois at Chicago, 845 West Taylor St., Chicago, IL 60607-7061, U.S.A.
Abstract
The conversion of thiophenecarboxaldehyde to thienylacetylene by the Corey procedure is associated with a concentration-dependent polymerization precess and an alkylation of the thiophene at the 2 position. Improvements in the synthesis of 2,2’:5’,2”-terthiophene and its 5,2”-dibutyl derivative are reported.
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■ Heterocycles. XVIII. Synthesis of the Racemates of Naturally Occurring Flavonoids
Hiroshi Takahashi, Yumiko Kubota, Mieko Iguchi, Lin Fang, and Masayuki Onda*
*School of Pharmaceutical Sciences, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
Racemic aromadendrin and fustin have been stereoselectively synthesized. Reduction of the O-substituted derivatives of these flavanonols provides the corresponding derivatives of gleditsin, leucopelargonidin and mollisacacidin (leucofisetinidin).
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■ Transformations of N-Heteroarylformamidines. A Novel Synthesis of Imidazo[2,1-b]thiazole and Imidazo[2,1-b][1,3,4]thiadiazole Derivatives
Simona Fajgelj, Branko Stanovnik,* and Miha Tisler
*Department of Chemistry, E. Kardelj University, Murnikova 6, 61000 Ljubljana, Slovenia
Abstract
Substituted imidazo[2,1-b]thiazole and imidazo[2,1-b][1,3,4]thiadiazole derivatives 3 and 9 were prepared from the corresponding thiazolylformamidine 2 by quaternization with phenacyl bromide and from the corresponding quaternized amino substituted 1,3,4-thiadiazole derivative 8 by treatment with DMFDMA, followed by cyclization and subsequent elimination of dimethylamine. This method represents a novel method for the preparation of imidazoazoles with a bridgehead nitrogen atom.
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■ A Novel Dimerization of a Pyridinium Ring Involving Linkage of the 2,5-Positions of One Ring to the 4’,3’-Positions of Another
Alan R. Katritzky,* Radi Awartani, Hassan Faid Allah, Bushra J. Agha, Gus Palenik, and Martin Gawron
*Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, P. O. Box 117200, Gainesville, FL 32611-7200, U.S.A.
Abstract
Decarboxylative dimerization of 1-(2’-pyridyl)-2-carboxy-4,6-diphenylpyridinium tetrafluoroborate monohydrate yields a novel cage coumpound. The structure is elucidated by X-ray and nmr spectroscopic methods.
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■ A Reinvestigation of the Synthesis of 1,2-Dihydro[1,2]diazepin-3-ones from Pyrones
Norton P. Peet* and Shyam Sunder
*Indianapolis Center, Merrell Dow Research Institute, 9550 Zionsville Road, indianapolis, Indiana 46268-0470, U.S.A.
Abstract
The reactions of 5-acetyl-6-hydroxy-4-(4-methoxyphenyl)-2H-pyran-2-one (5) and 4-(4-methoxyphenyl)-2H-pyran-2,6-dione (4) with hydrazine and phenylhydrazine respectively, gave the respective 1-amino-2-pyridones 8 and 11 rather than diazepinones 6 and 10, as previously reported. In addition. 4-(4-methoxyphenyl)-2-methyl-6-oxo-2H-pyran-3-carboxylic acid (14) gave p-methoxyacetophenone azine (16) upon treatment with hydrazine, rather than pyrazolodiazepinone 15.
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■ Synthesis, Metalation and Electrophilic Quenching of Alkyl-isoxazole-4-tertiary Carboxamides. A Critical Comparison of Three Isoxazole Lateral Metalation Methods
Chorng-Shyr Niou and Nicholas R. Natale*
*Department of Chemistry, University of Idaho, 301 Renfrew Hall, Moscow, ID 83844-2343, U.S.A.
Abstract
Alkyl-isoxazole-4-tertiary carboxamides are easily formed from isoxazole-4-carboxylic acids. Lateral metalation and electrophilic quenching was accomplished regioselectively at C-5 in synthetically useful yields. The chief advantage of this method is in the preparation of chiral isoxazole-4-tertiary carboxamides. The scope and limitations of this methodology is critically compared to lateral metalation of isoxazole-4-oxazolines and isoxazole carboxylic acid dianions.
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■ Analysis of the 1H-NMR Spectrum of the Antitumor Agent Mitindomide and Derivatives. An Unusual Example of Nonequivalent Vicinal Olefinic Protons
Howard M. Deutsch* and Leon H. Zalkow
*School of Chemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, U.S.A.
Abstract
The 1H-nmr spectrum of the antitumor agent mitindomide (1b) in DMSO-D6 solution has been completely analyzed by the use of homonuclear decoupling, NOE effects and specific deuterium labeling. A derivative of mitindomide, in which asymmetric groups were attached to the imide nitrogen (2c), showed magnetically nonequivalent diasteriotopic olefinic protons.
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■ Studies on Reactive Intermediates. Part V. Reaction of Ketene Dimer with Benzimidazole
Mohsen Daneshtalab* and Tetsuzo Kato
*Department of Chemistry, College of Pharmacy, Tehran University, Tehran 14, Iran
Abstract
Reaction of ketene dimer with benzimidazole in neat condition at room temperature, gave rise to 1-[o-(N-acetoacetylamino)phenyl]-3,5-diacetyl-4-hydroxypyridin-2(1H)-one (III), an adduct of one mole of benzimidazole and three moles of ketene dimer. Hydrolysis of compound III with 10 % hydrochloric acid gave the N-deacetoacetylated product (IV). Heatinq of compound III with 80 % sulfuric acid resulted in the formation of 1-(o-aminophenyl)-5-acetyl-4-hydroxypyridin-2(1H)-one (V). The reaction mechanism is discussed.
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■ The Synthesis of 5‘-Alkylnicotines
Makoto Shibagaki,* Hajime Matsushita, and Hajime Kaneko
*Life Science Research Laboratory, Japan Tobacco Inc., 6-2, Umegaoka, Midori-ku, Yokohama, Kanagawa 227-8512, Japan
Abstract
The reaction of cotinine(2) with alkyl lithium followed by the reduction with NaBH3CN in acidic methanol gave cis and trans-5’-alkylnicotines(3 and 4). The stereochemistry of the products was discussed.
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■ The Regioselective Preparation of 1-Alken-3-ones by the Reaction of 3-(1-Imidazolyl)-2-alken-1-ones with Organometallic Compounds
Choji Kashima,* Shegeki Hibi, Masao Shimizu, Tadakuni Tajima, and Yoshimori Omote
*Department of Chemistry, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan
Abstract
3-(1-Imidazolyl)-2-alken-1-ones, having substituent on the C-3 carbon, reacted with organometallic compounds to afford 3-(1-imidazolyl)-2-alken-1-ols. By the treatment of the products with sulfuric acid, 1-alken-3-ones, which were the positional isomers of the Michael addition products, was obtained regioselectively in good yields under mild conditions. Sodium borohydride reduction was also investigated.
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■ Further Evidence for the Structure of Bianfugecine
Jun-ichi Kunitomo* and Yohko Miyata
*Faculty of Pharmaceutical Science, Mukogawa-Women’s University, 11-68 Koushien Kyuban-Cho, Nishinomiya, Hyogo 663-8179, Japan
Abstract
The structure of bianfugecine was unequivocally represented by formula (2) by chemical correlation of bianfugecine (2) with structurally established menisporphine (1).
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■ Synthesis of α-Methylene-γ-butyrolactones
Jadab C. Sarma and Ram P. Sharma*
*Division of Natural Products Chemistry, Regional Reseach Labratory (CSIR), Jorhat-6, Assam, India
Abstract
Synthesis of α-methylene-γ-butyrolactone moiety present in numerous natural products displaying a wide range of biological activity has been reviewed here embracing the period from 1980 to the middle of 1985.