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. 19, No. 4, 1982
Published online:
■ Reactions of 5,6-Diamino-1,3-dimethyluracil with D-Xylose. Synthesis of 7-Xylopyranosylxanthine
Rodrigo Rico Gomez
*Departamento de Quimica Organica, Facultad de Ciencias, Universidad de Málaga, Campus de Teations, E-29071 Malaga, Spain
Abstract
6-Amino- and 6-acetylamino-5-(xylopyranosyl)acetylamino-1,3-dimethyluracils are synthetised from 4-amino-5-xylosylidenimino-1,3-dimethyluracil. Cyclisation to 7-xylopyranosylxanthine is carried out from both 6-amino- and 6-acetylamino derivatives.
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■ 2-tert-Butyl-2H-benzo[f]isoindole
Richard Kreher and Götz Use
*Institut für Chemie, Medizinische Hochschule Lübeck, Ratzeburger Allee 160, D-2400, Germany
Abstract
The tricyclic 14π-system can be prepared via a convenient route developed for 2H-isoindoles. The investigated cycloaddition and substitution reactions reveal relations between structure and property and confirm theoretical predictions.
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■ On Cardioactive Steroids VI. The Synthesis of 17α-Methyl Cardenolides
Karnail S. Atwal, Soumya P. Sahoo, Thomas Y. R. Tsai, and Karel Wiesner
*Natural Products Research Center, Department of Chemistry, University of New Brunswick, Bag Service #45222, Fredericton, New Brunswick, E3b 5A3, Canada
Abstract
Two methods for the simple synthesis of the Δ14,15-17α-methyl cardenolide 1 are disclosed. This material may be functionalized to a variety of 17α-methyl derivatives for pharmacological testing. As an example, the preparation of 17α-methyl digitoxigenin 20 is described.
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■ On Cardioactive Steroids VII. The Conversion of Digitoxigenin to Isomers of Natural Bufalin and Resibufogenin
Franz Josef Jäggi, Thomas Y. R. Tsai, and Karel Wiesner
*Natural Products Research Center, Department of Chemistry, University of New Brunswick, Bag Service #45222, Fredericton, New Brunswick, E3b 5A3, Canada
Abstract
A high yield conversion of digitoxigenin I to α-isobufalin 1 and β-isoresibufogenin 2 is described.
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■ Synthesis of Dihydroisoquinolines and 1-Substituted Tetrahydroisoquinolines
Frank E. Scully, Jr. and John J. Schlager
*Department of Chemical Sciences, Old Dominion University, Norfolk, Virginia 23508, U.S.A.
Abstract
A simple synthesis of three dihydroisoquinolines and five 1-substituted tetrahydroisoquinolines from the parent compound involves N-chlorination/dehydrochlorination with KO2 and subsequent organometallation.
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■ Preparation and Assignment of Selenium Analoges of Benzo-1,2-dithiole-3-thione
Shigeru Oae, Keishi Sakai, Mitsuo Fukumura, Seizo Tamagaki, Yashiki Matsuura, and Masao Kakudo
*Department of Chemistry, University of Tsukubaa, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan
Abstract
The product formed in the reaction of benzo-3-methylthio-1,2-dithiolium iodide with sodium hydrogen selenide was assigned as benzo-1,2-thiaselenole-3-thione(I) by X-ray crystallographic techniques. (I) crystallizes in a monoclinic space group P21/c with a=13.01, b=4.10, c=28.51 Å, β=90.50° and z=8. While, treatment of benzo-3-chloro-1,2-dithiolium perchlorate with sodium O,O-diethyl phosphoroselenate gave benzo-1,2-dithiole-3-selone(II) in a moderate yield. The structure of the compound(II) has also been confirmed by X-ray crystallographic techniques. (II) crystallizes in a monoclinic space group P21/c with a=4.06, b=10.83, c=17.75 Å, β=98.81° and z=4. Selone(II) was isomerized to the thione(I) thermally, whereas the latter (I) was not converted to any other product.
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■ Indoloquinolizidine N-Oxides and Polonovski Rearrangement
Masako Nakagawa, Yoshimitsu Ogawa, Yuko Miyake, Keiichi Yamaguchi, Tohru Hino, Chian C. Chinag, Judith L. Flippen, and Bernhard Witkop
*Faculty of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
Abstract
The structures of two (±)-indoloquinolizidine N-oxides 3a and 3b were determined unequivocally. Their Polonovski rearrangements gave 4, 5, and 1 with acetic anhydride in acetic acid and gave a complex molecule 12 with acetic anhydride.
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■ Diazapolycyclic Compounds XXII. The Action of N-Chlorosuccinimide over Diazaquinone Adducts under Ionic and Free Radical Conditions
Fernando Gómez Contreras and Ana María Solana
*Departamento de Química Orgánica y Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain
Abstract
The action of N-chlorosuccinimide over 4a,12a-diazatetracyclic systems obtained by cycloaddition of benzo(g)phthalazine-1,4-dione with several dienes is reported. The reaction in acid aqueous medium leads to the formation of 1,2-chlorohydrins by ionic addition to the double bond at the terminal tetrahydropyridazine ring moiety. The stereochemical results of these additions are commented, and it can be deduced that the usual AdE2 mechanism is not followed. When the conditions favoring a free radical process are employed, the addition process is accompanied by substitution at the terminal aromatic ring.
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■ Reactions with Thiohydantoins: A Novel Synthesis of Thiopyrano[2,3-d]imidazoles
Hamed A. Daboun, Mahfouz A. Abdel Aziz, and Fatma A. Abdel Aal
*Department of Chemistry, Faculty of Science, , University of Cairo, Giza, Egypt
Abstract
A novel synthesis of thiopyrano[2,3-d]imidazoles via reaction of acrylonitrile, ethyl acrylate and N-p-chlorophenylmaleimide with 5-arylidene-3-phenyl-4-thiohydantoins is reported. The reaction of acrylonitrile with hydantoins and 2-thiohydantoins is also reported and discussed.
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■ Polycondensed Nitrogen Heterocycles. Part XI. 1,3-Disubstituted 2-Methylpyrrolo[3,2-c]cinnoline and 2-Acetyl-3-methylpyrrolo[1,2-c]banzo[1,2,3]triazine
Gaetano Dattolo, Girolamo Cirrincione, Anna Maria Almerico, Isabella D’Asdia, and Enrico Aiello
*II Cattedra di Chimica Farmaceutica, Università digli Studi di Palermo, Via Archirafi 32, 90123 Palermo, Italy
Abstract
The diazotization of 1,3-disubstituted 2-methyl-5-(2-aminophenyl)pyrroles (2) and the intramolecular coupling reaction of the resulting diazonium salts lead to pyrrolo[1,2-c]benzo[1,2,3]triazine 4 when R = H. Pyrrolo[3,2-c]cinnolines 3, a new ring system, were obtained when R ≠ H. Compound 3d inhibited the germination of seeds of Echinochloa crus-galli.
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■ Synthesis of 3-Methylxanthosine
Taisuke Itaya and Tsunehiro Harada
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Treatment of 1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-5-(methylamino)imidazole-4-carboxamide (VIb) with EtOCOCl followed by cyclization with 1 N NaOH gave 3-methylxanthosine (Va). The glycosidic bond of Va underwent acid hydrolysis at a rate more than 1000 times greater than that of xanthosine.
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■ Synthesis of Weberine and Norweberine and Their 1-Methyl Congeners
Kimio Takahashi and Arnold Brossi
*Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestve and Kidney Diseases, National Institute of Health, Bethesda, MD 20892-0820, U.S.A.
Abstract
The synthesis of 2-methyl-5,6,7,8-tetramethoxy-1,2,3,4-tetrahydroisoquinoline (weberine) 5 from 2,3,4,5-tetramethoxy-β-phenylethylamine via norweberine 4 is described. The synthesis of their 1-methyl homologs was also accomplished.
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■ A Convergent Synthetic Route to the Quettamines and the 7,8-Dioxygenated Tetrahydrobenzylisoqunoline Alkaloids
Sankar Chattopadhyay and Maurice Shamma
*Department of Chemistry, The Pennsylvania State University, York Campus, P1031 Edgecomb Avenue, York, Pennsylvania 17403, U.S.A.
Abstract
(±)-Quettamine (1) chloride, (±)-norjuziphine (12), (±)-juziphine (13) and (±)-oblongine (14) iodide have been synthesized.
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■ Studies on Ketene and Its Derivatives (CVIII). Photoreaction of Diketene with Uracil (Complement)
Takuo Chiba, Hitoshi Takahashi, and Tetsuzo Kato
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
Photoreaction of diketene with uracil gave the [2+2]spirocycloadduct, which was, on thermolysis, transformed to 7- and 8-methylene-2,4-diazabicyclo[4.2.0]octane-3,5-dione (5) and (6). Bromination of compound (5) followed by the treatment with sodium ethoxide gave 5-methylene-5,6-dihydro-1H,3H-cyclobuta[e]pyrimidine-2,4-dione (7).
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■ Conversion of Ethyl Cincholoiponate into a Tricyclic Intermediate Adaptable to Chiral Syntheses of 10-Demethylated Alangium Alkaloids
Tozo Fujii, Masashi Ohba, and Hitoshi Suzuki
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
The title (—)-tricyclic amino ester VII has been synthesized by means of an initial condensation of 4-benzyloxy-3-methoxyphenacyl bromide with (+)-ethyl cincholoiponate (VIII) , derived from the Cinchona alkaloid cinchonine, and succeeding steps proceeding through the intermediates (+)-IX, X, XI, (—)-XIII, (—)-XIV, (+)-XV, (+)-XVI, (+)-XVII, and XVIII.
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■ Oxaza and Dioxaza Medium-sized Heterocycles and Benz-fused Derivatives
John B. Bremner, Elaine J. Browne, and Indrani W. K. Gunawardana
*Department of Chemistry, University of Tasmania, GPO Box 252C Hobart, Tasmania, 7001, Australia
Abstract
This review summarises the preparations and some properties of oxaza and dioxaza medium-ring systems (8-11 membered rings), and their benz-fused derivatives. Classification within each group has been made on the type of operation involved in the ring forming process, viz. ring construction, ring destruction, or ring interconversion.