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. 14, No. 3, 1980
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■ A Convenient Synthesis of Pyridazino[4,5-b]quinolines and Pyrrolo[3,4-b]quinolines
Yoshihisa Kurasawa* and Atsushi Takada
*School of Pharmaceutical Sciences, Kitasato University, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
Pyridazino[4,5-b]quinolines were conveniently synthesized from the reaction of N-(1,2-bisethoxycarbonylvinyl)-o-aminoacetophenone with hydrazines, and 2,3-bishydrazinocarbonyl-4-methylquinolines were easily cyclized to pyrrolo[3,4-b]quinolines.
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■ The Synthesis of 1,4-Selenathiafulvenes
M. V. Lakshmikantham and Michael P. Cava*
*Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia, PA 19104-6323, U.S.A.
Abstract
The first examples (18 and 19) of 1,4-selenathiafulvenes are described. These compounds were prepared by a Wittig-type synthesis from the appropriate aldehydes and 1,3-selenathiolyl phosphonium salts (9 and 11) in methanol, using KOH as the base. The same reaction conditions also afforded a number of 1,4-dithiafulvenes, the Wittig synthesis of which has previously been achieved only under aprotic conditions.
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■ A Novel Synthesis of Indoel Derivatives
Tetsuji Kametani,* Tatsushi Ohsawa, and Masataka Ihara
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
1-Acetyl-2,3-dihydro-5,6-dimethoxy-1H-indole (13) was synthesized by cyclization of N-(2-bromo-4,5-dimethoxyphenethyl)-acetamide (6) using sodium hydride and cuprous halide in dimethylformamide. Indoles (14, 15 and 16) were prepared in a similar manner from the corresponding amides (8 and 10) and the carbamate (12). Under similar reaction conditions, phenylacetamides (20 and 21) afforded the oxindoles (22 and 23).
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■ A New Synthesis of Furo[2,3-b]quinoxaline and Its Ring Conversions
Yoshihisa Kurasawa* and Atsushi Takada
*School of Pharmaceutical Sciences, Kitasato University, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
A new synthesis of 3-(N,N-dimethylaminocarbonyl)furo[2,3-b]quinoxaline was described. This compound was converted to 2-ethoxycarbonylmethylene-3-oxo-1,2,3,4-tetrahydroquinoxaline, 2-methyl-3-oxo-3,4-dihydroquinoxaline, 4-(3’-oxo-3’,4’-dihydroquinoxalin-2’-yl)pyrazolones, and pyrazolo[3,4-c]pyridazino[3,4-b]quinoxalines.
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■ Facile Oxidation of 2-Oxo-1,4,6-trisubstituted 1,2,3,6-Tetrahydropyrimidines with Chloranil
Choji Kashima,* Akira Katoh, Yuko Yokota, and Yoshimori Omote
*Department of Chemistry, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan
Abstract
2-Oxo-1,4,6-trisubstituted 1,2,3,6-tetrahydropyrimidines (1a-1h) were easily oxidized with 2,3,5,6-tetrachloro-1,4-benzoquinone(chloranil) to afford the corresponding 1,4,6-trisubstituted 2(1H)-pyrimidinones (2) in good yields.
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■ A Simple Method for the Preparation of Some Amino N-Heteroaromatics
Tokuhiro Watanabe, Etsuko Kikuchi, Wataru Tamura, Yasuo Akita, Mayumi Tsutsui, and Akihiro Ohta*
*Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
Abstract
The heating of some halogenated pyrazines, pyridines, and quinolines with benzamide in the presence of potassium carbonate gave the corresponding amino derivatives. The similar reaction using acetamide afforded acetamido derivatives, together with amines in some cases.
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■ The Reaction of O-Ethylsuccinimide with Aryllithium Compounds: An Efficient Method for the Introduction of 3-Ethoxycarbonylpropionyl Group to Aromatic Compounds
Tatsuo Nagasaka,* Fumiko Hamaguchi, Naganori Ozawa, Yoshiyuki Kosugi, and Sadao Ohki
*School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
Abstract
O-Ethyl succinimide (I) was found to be an efficient reagent for the introduction of 3-ethoxycarbonylpropionyl group (-COCH2CH2COOEt) to aromatic compounds by a single operation under mild conditions.
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■ Structure of Ephedradine C, a Hypotensive Principle of Ephedra Roots
Chohachi Konno, Mitsuru Tamada, Katsuya Endo, and Hiroshi Hikino*
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
From the crude drug “mao-kon”, the roots of Ephedra plants, a novel macrocyclic spermine alkaloid ephedradine C exhibiting the hypotensive activity has been isolated whose stereostructure has been established as represented by formula I on the basis of chemical and physical evidence. Flexibility of the molecules of the ephedradines has been noticed by means of NMR and CD spectroscopy.
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■ A Synthesis of (±)-9-Demethyltubulosine
Masashi Ohba, Mitusko Hayashi, and Tozo Fujii*
*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 VII through the intermediates VIII, IX, and IV. Nonconformity of synthetic (±)-I with demethyltubulosine indicated the alternative 10-demethyl structure (V) to be the correct expression for this Alangium alkaloid.
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■ The Total Stereoselective Retro Mass Spectral Synthesis of (±)-Emetine
Tetsuji Kametani,* Samuel A. Surgenor, and Keiichiro Fukumoto
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
A new route to (±)-emetine (18) via the Michael addition product (4A) is described. Addition of 3,4-dihydro-6,7-dimethoxy-1-methylisoquinoline (3) to the α,β-unsaturated ester (2) afforded 2-(3’,4’-dihydro-6’,7’-dimethoxy-1’-isoquinolinylmethyl)-3-methoxycarbonyl-1,2,3,6,7,11b-hexahydro-9,10-dimethoxybenzo[a]quinolizin-4-one (4A) which was converted to (±)-emetine in 6 steps.
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■ Direct Synthesis of Some 9-Aminoalkylacridines from 9-Aminoacridine Using Phase Transfer Catalysis
Jean Pierre Galy, José Elguero, Emile Jean Vincent, Anna-Marie Galy, and Jaques Barbe*
*Laboratoire de Chimie Minérale, U. E. R. de Pharmacie, Université de la Mediterranee de Marseille, 27, Bd Jean-Moulin 13385 Marseille Cedex 5, France
Abstract
A new method of preparation of 9-aminoalkyl acridines is described which avoid the use of 9-chloroacridine. Proton n.m.r. in trifluoroacetic acid easily differentiates 9-aminoalkyl from 9-amino 10-alkyl acridinium salts. Two dialkyl iminoacridanes have been obtained.
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■ Synthesis of Bicyclic Intermediates for Diterpenoid Alkaloids
Ajoy K. Banerjee,* Pedro C. Caraballo, Héctor E. Hurtado, and María C. Carrasco
*Centro de Química, Instituto Venezolano de Investigaciones Científicas, I.V.I.C., Apartado 21827, Caracas 1020-A, Venezuela
Abstract
Synthesis of ester 9 from olefin 1 is described. Transformation of 9 to lactams 20 and 21 has been realized.
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■ New Heterocyclic Systems: Thiophene Condensed 1-Aza-bicyclo[3.3.1]nonanes
Jean-Pierre Maffrand,* Fernand Eloy, and Marc Lucas
*Department Recherche et Developpement, Linge Hèmobiologie, Parcor, 195, route d’Espagne 31024 Toulouse Cedex, France
Abstract
We described the synthesis of new heterocyclic systems by acidic treatment of N-benzyl, N-thenyl or N,N-dithenyl aminoacetaldehyde dimethylacetals.
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■ Base Induced Reactions of N-Methyl Quaternary Salts of Thiophene Condensed 1-Aza-bicyclo[3,3,1]nonanes
Jean-Pierre Maffrand and Marc Lucas
*Department Recherche et Developpement, Linge Hèmobiologie, Parcor, 195, route d’Espagne 31024 Toulouse Cedex, France
Abstract
Reactions of N-methyl quaternary salts of thiophene condensed 1-aza-bicyclo[3,3,1]nonanes with various bases were examined in order to obtain preferentially Hofman elimination or Stevens rearrangement.
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■ A New Method for Synthesis of Lactam
Yoshihisa Kurasawa and Atsushi Takada
*School of Pharmaceutical Sciences, Kitasato University, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
2-Substituted 3-oxo-3,4-dihydroquinoxalines were oxidized with H2O2 to 2,3-dioxo-1,2,3,4-tetrahydroquinoxaline. This oxidation of the imino bonding in the heterocycles to the lactam was assumed to proceed via the various peroxides, but not via the oxaziranes.
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■ Synthetic Approaches to the 4H-Pyran Ring
C. Seoane, J. L. Soto, and M. Quinterio
*Departamento de Química Orgánica I., Facultad de Química, Universidad Complutense de Madrid, Ciudad Universitaria, E-28040 Madrid, Spain
Abstract
This article presents a systematization of the available synthetic procedures for the preparation of 4H-pyrans.