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. 31, No. 4, 1990
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■ Efficient Enzymatic Cyclization of 2-(Carbamoyloxy)- and 2-(Sulfamoyloxy)benzonitriles by Ultrasonically Stimulated Baker’s Yeast
Ahmed Kamal,* Maddamsetty V. Rao, and Adari B. Rao
*Organic Chemistry Division III, Indian Institute of Chemical Technology, Hyderabad 500 007, India
Abstract
An approach to the synthesis of 4-imino substituted 1,3-benzoxazin-2-ones, 1,2,3-benzoxathiazin-2-ones and 2-quinazolinones based on the enzymatic cyclization of the labile-functionalized compounds with ultrasonically stimulated baker’s yeast.
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■ Conformational Analyses of Stegobinone and 1’-Epi-stegobinone
Takashi Ebata,* Koshi Koseki, Kazuko Shimazaki, Hiroshi Kawakami, Tatsuji Chuman, Hajime Matsushita, and Kenji Mori
*Life Science Research Laboratory, Japan Tobacco Inc., 6-2, Umegaoka, Midori-ku, Yokohama, Kanagawa 227-8512, Japan
Abstract
Conformational analyses of stegobinone 1, the sex pheromone of the drugstore beetle, and 1’-epi-stegobinone 2 were performed by the combination of detail NOE measurements and molecular mechanics caluculations.
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■ 1,6-Electrocyclization Reactions of Acceptor-substituted 2,3-Divinylindoles to Functionalized Carbazoles
Ulf Pindur* and Reinhard Adam
*Department of Chemistry and Pharmacy, University of Mainz, Saarstrasse 21, D-6500 Mainz 1, Germany
Abstract
The synthesis and thermal 1,6-electrocyclization reactions of acceptor-substituted 2,3-vinylindoles, which give rise to functionalized carbazole derivatives, are described.
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■ Cycloaddition Reactions of 6-Cyanobenz[a]indolizines with Activated Alkynes. Formation of Benzo[2.2.3]- and [2.3.4]cyclazines
Kiyoshi Matsumoto,* Takane Uchida, Tomoe Kato, Mitsuo Toda, Kinuyo Aoyama, and Hideyuki Konishi
*College of Liberal Arts and Science, Kyoto University, Kyoto 606, Japan
Abstract
Cycloaddition reactions of 6-cyanobenz[a]indolizines with activated alkynes such as dimethyl acetylenedicarboxylate, diacetylacetylene, methyl propiolate, methyl trimethylsilylpropiolate, methyl phenylpropiolate, and 4-phenyl-3-butyn-2-one were investigated.
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■ An Alternative Total Synthesis of (+)-Pallescensin A Based on the Intramolecular [3+2] Cycloaddition Reaction
Kozo Shishido,* Koji Umimoto, and Masayuki Shibuya
*Faculty of Pharmaceutical Sciences, University of Tokushima, Sho-machi 1, Tokushima 770, Japan
Abstract
An alternative total synthesis of optically active pallescensin A is described which features a furan construction via the intramolecular [3+2] cycloaddition of nitrile oxide.
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■ 1’-Methylzeatin and its 9-β-D-Ribofuranoside: The Carbon-13 Nuclear Magnetic Resonance Spectra Revised
Masashi Ohba, Tozo Fujii,* Antonio Evidente, Guiseppe Surico, and Nicola S. Iacobellis
*Faculty of Pharmaceutical Scicences, Kanazawa University, Takara-machi, Kanazawa 920, Japan
Abstract
Revised carbon-13 chemcial shift assignments are reported for the cytokinins (1'R)-1'-methylzeatin [(1'R)-1] and its 9-β-D-ribofuranoside [(1"R)-2]. Previous shift assignments for the two methyl carbons in the purine N6 side chain of (1'R)-1 and (1"R)-2, as well as those for the C(2') and C(3') carbons of (1"R)-2, have now been reversed by comparison with the 13C nmr data for the diastereomeric nucleoside (1"S)-2 and the cis isomers 3 and 4.
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■ Synthesis of 2,4-Dihydropyrrolo[3,4-b]pyrroles and 4,6-Dihydro-2H-dipyrrolo[3,4-b:3’,4’-d]pyrroles
Chin-Kang Sha,* Jia-Ming Liu, Ray-Kuang Chiang, and Sue-Lein Wang
*Department of Chemistry, National Tsing Hua University, Hsinchu 30043, Taiwan, R.O.C.
Abstract
The labile heterocyclic ring systems, 2,4-dihydropyrrolo[3,4-b]pyrrole 1 and 4,6-dihydro-2H-dipyrrolo[3,4-b:3’,4’-d]pyrrole 2, were prepared readily by the phosphineimine-alkylidenemalonate cyclization reaction or the retro-malone addition reaction. An X-ray structure analysis confirmed that three pyrrole rings of 2 are coplanar.
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■ Studies on Alkyl Isocyanoacetates and Related Compounds. Synthesis of 6-Arylthio-8-ethoxycarbonyl-4-ethoxycarbonylmethylaminoimidazo[5,1-b][1,3,5]thiadiazine-2-thiones
Ricardo Bossio,* Stefano Marcaccini, Monica Muratori, Roberto Pepino, and Giovanni Valle
*CNR, Centro di Studio Sulla Chimica e la Struttura dei Composti Eterociclici e lolo Applicazioni, c/o Dipartimento di Chimica Organica "Ugo Schiff", Università di Firenze, Via Gino Capponi 9, I-50121 Firenze, Italy
Abstract
N-Ethoxycarbonylmethyl-S-arylisothiocarbamoylisothiocyanates (4) upon treatment with NEt3 and then with HCl afforded 6-arylthio-8-ethoxycarbonyl-4-ethoxycarbonylmethylaminoimidazo[5,1-b][1,3,5]thiadiazine-2-thiones (6).
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■ Reactivity Parameters of the Metal Assisted 1,2-Cleavage of Penicillins
Marco Alpegiani, Angelo Bedeshci, Pierluigi Bissolino, Giuseppina Visentin, Franco Zarini, Ettore Perrone, and Giovanni Franceschi
*Farmitalia Carlo Erba - R. & D., Infectiond Diseases Dept., Via dei Gracchi, 35 - 20146 Milan, Italy
Abstract
A straightforward and smooth conversion of penicillins into 1,2-secopenicillanates is described. The thiazolidine ring opening is brought about by the co-operative effect of strong non-nucleophilic bases and thiophilic heavy metal salts. The nature of the latter and the polarity of the solvent profoundly affect the reaction rate. Best general conditions can be drawn for the conversion of numerous 6-substituted penicillanates wth various protecting groups on the carboxy function.
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■ Four New Phenolic Constituents from Licorice (Root of Glycyrrhiza Sp.)
Fumiyuki Kikuchi, Xing Chen, and Yoshisuke Tsuda*
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Four new isoprenoid-substituted phenolic constituents, semmilicoisoflavone B (1), isoangustone A (2), 1-methoxyficifolinol (3), and licoriphenone (4), along with nine known phenolic compounds, were isolated from a commercial licorice (root of Glycyrrhiza sp.) and their structures were elucidated on the basis of spectroscopic and chemical means.
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■ A Convenient Synthesis of 2,4’-Bipyridine
Min-Jen Shiao* and Kai-Yih Tarng
*Institutue of Chemistry, Academia Sinica, 128, Yan-Chiu-Yuan Road, Sec II, Nankang, Taipei,11529, Taiwan, R.O.C.
Abstract
2,4’-Bipyridine 6 was synthesized starting from N-ethoxycarbonylpyridinium chlorid 1 and 2-benzyloxy-6-bromopyridine 2a or 6-bromo-2-methoxypyridine 2b via 6-benzyloxy2,4’-bipyridine 3a or 6-methoxy-2,4’-bipyridine 3b and 6-chloro-2,4’-bipyridine 5.
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■ Structures of Prenylated Dihydrochalcone, Gancaonin J and Homoisoflavonone, Gancaonin K from Glycyrrhiza pallidiflora
Toshio Fukai, Qing-Hua Wang, Ryouhei Inami, and Taro Nomura*
*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan
Abstract
A new prenylated dihydrochalcone, gancaonin J and a homoisoflavanone, gancaonin K, along with fourteen known compounds were isolated from the root of Glycyrrhiza pallidiflora MAXIM. Structures of gancaonins J and K were shown to be 1 and 2, respectively, on the basis of spectral evidence. Gancaonin K (2) and 2’-O-methyllicodione (17) being isolated from the same material, thelatterseems to be a biogenetical precursor of 2. From the aerial parts of G. pallidiflora MAXIM., two known phenolic compounds were isolated.
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■ Furan o-Aminonitriles as Precursors to Flavone Analogues
Stephen J. Cutler, Fiesal M. El-Kabbani, Charlene Keane, Sherri L. Fisher-Shore, and C. Dewitt Blanton, Jr.*
*Department of Medical Chemistry and Pharmacognosy, College of Pharmacy, The University of Georgia, Athens, Georgia 30602, U.S.A.
Abstract
A procedure utilizing furan o-aminonitriles as precursors in the synthesis of substituted flavone analogues is reported. The key intermediates, o-hydroxyacetophenones, are obtained by a Diels-Alder reaction betweenthe furans and methyl vinyl ketone.
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■ Synthesis of 4-Acylisoxazole-5-carboxylates via 1,3-Dipolar Cycloaddition Reaction of β-Acylpyruvates with Nitrile Oxides in the Absence of Base
Jae Nyoug Kim and Eung K. Ryu*
*Division of Organic Chemistry, Korea Research Institute of Chemical Technology, P.O.Box 9, Daedeog Danji, Daejoen 305-606, Korea
Abstract
The fully substituted isoxazole derivatives 3 were prepared in moderate to high yields via the cycloaddition reaction of nitrile oxides with β-acylpyruvates 2. β-Acylpyruvates, unlikely ordinary β-diketones, show high dipolarophilic reactivity toward nitrile oxides in the absence of base.
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■ Synthesis Esters and Ethers of Delphinine and Lycoctonine
S. William Pelletier* and Samir A. Ross
*Institute for Natural Products Research and School of Chemical Sciences, The University of Georgia, Chemistry Building, Athens, Georgia 30602-2556, U.S.A.
Abstract
This paper reports the synthesis and spectral data for 8,13,14-triacetyldelphonine (1), 13benzoyldelphinine (2), 13-O-methyldelphinine (3), 18-p-anisoyllycoctonine (4), 18-o-anisoyllycoctonine (5), 18-p-nitrobenzoyllycoctonine (6), 18-(3,4,5-trimethoxybenzoyl)lycoctonine (7), 18-stearoyllycoctonine (8), 18-lauroyllycoctonine (9), 18-linoleoyllycoctonine (10), lycoctonine 18-O-p-phenylbenzyl ether (11), and lycoctonine 18-O-ethyl ether (12).
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■ A Convenient Synthesis of 3-Heteroarylthiomethyl-1H,8H-cyclohepta[d]pyrazol-8-ones
Itsuko Kishi, Kimiaki Imafuku,* Kazuo Ogawa, and Yoh-ichi Matsushita
*Department of Chemistry, Faculty of Science, Kumamoto University, Kurokami 2-39-1, Kumamoto 860-8555, Japan
Abstract
The reactions of 3-(bromoacetyl)tropolone (1) with benzenehiol (2a) and heteroarenethiols (2b-f) gave 3-[(phenylthio(acetyl]tropolone (3a) and 3-[(heteroarylthio)acetyl]tropolones (3b-f), respectively. These compounds (3a-f) reacted with hydrazine hydrate and methylhydrazine to afford 3-phenylthiomethyl- (4a) and 3-heteroarylthiomethyl-1H,8H-cyclohepta[d]pyrazol-8-ones (4b-f) and their corresponding 1-methyl substituted compounds (5b-f), respectively
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■ Preparation of Alkyl-substituted Indoles in the Benzene Portion. Part 3
Hideaki Muratake and Mitsutaka Natsume*
*Research Foundation Itsuu Laboratory, 2-28-10 Tamagawa, Setagaya-ku, Tokyo 158, Japan
Abstract
Three-step synthesis of 7- and 4-alkyl-1-tosylindoles (9 and 10) was accomplished by combination of the Friedel-Crafts acylation of 4, and the treatment of 7 and 8 with H2SO4 in 2-propanol as illustrated in Chart 2. Further a novel synthetic method of 16 was devised from 14 by way of 15.
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■ Preparation of Alkyl-substitued Indoles in the Benzene Protion. Part 4
Hideaki Muratake and Mitsutaka Natsume*
*Research Foundation Itsuu Laboratory, 2-28-10 Tamagawa, Setagaya-ku, Tokyo 158, Japan
Abstract
A useful method for the preparation of variously substituted polyalkylindoles (3b) was established by H2SO4-catalyzed cyclization reaction of 1b, where the substituent Y was designated as either the hydroxy or alkoxy group, to yield 3a in good yields. The substrate (1b) was prepared from 1-phenylsulfonylpyrrole (5) by way of 1-phenylsulfonyl-2-pyrrolyl derivatives (4), e.g., 6 and 13, followed by the aldol reaction for the elongation of their carbonyl functions.
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■ The Chemistry of 4H-1,3-Dithiins
Fillmore Freeman*
*Department of Chemistry, University of California, Irvine, Irvine, California 92717, U.S.A.
Abstract
1,2-Dithiins, 1,3-dithiins, 1,4-dithiins, nd their derivatives continue to attract considerable attention owing to their bioactivity, to their unique structural features, to their potential superconducting properties, and to their chemical activity. This review describes the preparation, the chemistry, and the biological properties of 4H-1,3-dithiin and its derivatives.
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■ Photochemistry of 2(3H)- and 2(5H)-Furanones
Luis Fillol, Miguel A. Miranda,* Isabel M. Morera, and Hamid Sheikh
*Departamento de Química Oránica, Facultad de Farmacia, Av. Blasco Ibañez 13, 46010 Valencia, Spain
Abstract
The most general photoreaction of 2(3H)-furanones 1 is singlet mediated decarbonylation to vinyl ketones, although in some cases the formation of cyclobutane dimers and oxetanes has been observed. On the other hand, 2(5H)-furanones 2 preferentially undergo dimerization, cycloaddition or hydrogen abstraction from their triplet states. For these compounds, decarboxylation or nucleophilic solvent addition have also been reported. Other processes, observed only in the presence of the appropiate substituents, are stilbene-phenanthrene cyclization or substituents, are stilbene-phenanthrene cyclization or substituent migrations (from 1 and 2), as well as chromone formation or fragmentation (from 1).