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. 22, No. 5, 1984
Published online:
■ 2,3,8-Triazabicyclo[3.3.1]non-3-ene. A New Heterocyclic System
Joan Bosch,* Mario Rubiralta, Natividad Valls, and Anna Diez
*Laboratory of Organic Chemistry, Faculty of Pharmacy, University of Barcelona, Av. de Joan XXIII, s/n, 08028 Barcelona, Spain
Abstract
The formation of 2,3,8 -triazabicyclo[3.3.1]non-3-ene system by reaction of 4-acyl-1,2,3,4-tetrahydropyridines with hydrazine is described.
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■ Synthesis of 7-Substituted 4H-1,4-Benzothiazines
Radha Raman Gupta,* Rakesh Kumar Gautam, and Rakesh Kumar
*Department of Chemistry, University of Rajasthan, Jaipur 302 004, India
Abstract
One step synthesis is reported for 7-substituted 4H-1,4-benzothiazines involving the condensation of 5-substituted 2-aminobenzenethiols with p-methoxy and p-methylbenzoylacetone in DMSO which causes oxidative cyclisation.
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■ Heterocycles. XIV. Efficient Stereocontrolled Synthesis of Racemic Flavonoids
Hiroshi Takahashi, Yumiko Kubota, Hiroko Miyazaki, and Masayuki Onda*
*School of Pharmaceutical Sciences, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
Stereocontrolled synthesis of the flavonoids (2, 4 and 5) is described. Racemlc taxiolin (dihydroquercetin) (14) is synthesized by application of this method.
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■ A Novel Preparation of the 1,3-Benzoxazepine Ring System
Alan R. Katritzky,* Olga Rubio, Radi Awartani, Nazih Latif, Nawal Mishriky, and Fahmy M. Assad
*Center for Drug Discovery, College of Pharmacy, University of Florida, Gainesville, Florida 32611-7200, U.S.A.
Abstract
Novel 1,3-benzoxazepines (5) are obtained by a new ring expansion rearrangement of benzinones (1).
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■ Unsaturated β-Lactams
Marion Thielmann and Ekkehard Winterfeldt*
*Institut fur Organische Chemie, Universität Hannover, Schneiderberg 1 B, D-30167 Hannover, Germany
Abstract
Lithium enolates of β-lactams are shown to exclusively yield 1,2-addition products to propargylic aldehyde. Products of subsequent Peterson elimination and propargylic rearrangements are described.
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■ Studies on Phenothiazines. Part 10: Synthesis of 1-Ethoxy-7-substituted Phenothiazines
Radha Raman Gupta* and Rakesh Kumar
*Department of Chemistry, University of Rajasthan, Jaipur 302 004, India
Abstract
Synthesis of 1-ethoxy-7-substituted phenothiazines via Smiles rearrangement is reported. 2-Amino-3-ethoxybenzenethiol was condensed with halonitrobenzenes and the substituted diphenylsulphides, so obtained, were converted into substituted formyl derivatives by formic acid. The latter on treatment with alcoholic KOH underwent Smiles rearrangement and yield 1-ethoxy-7-substituted phenothiazines. The structure of the synthesized compounds have been confirmed by their elemental analysis and spectral studies.
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■ Ring Bromination in the Attempted Nitration of 2,5-Dibromo-3-dibromomethylthiophen
John D. Coyle,* Edmund J. Haws, Olufemi Oduntan, and John T. Rogers
*Chemistry Department, The Open University, Milton Keynes MK7 6AA, U.K.
Abstract
Treatment of 2,5-dibromo-3-dibromomethylthiophen with mixed nitric and sulphuric acids or with fuming (>96%) nitric acid gives 2,4,5-tribromothiophen-3-carbaldehyde after aqueous work-up.
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■ Pseudoesters and Derivatives. XXI. The Reaction of 4-Bromo-5-methoxy-3-pyrrolin-2-one with Nucleophiles
M. Angeles Jiménez, M. Carmen Ortega, Amelia Tito, and Francisco Fariña*
*Instituto de Quimica Organica General, Consejo Superior Investigaciones Cientificas, Calle Juan de la Cierva, 3, E-28006 Madrid, Spain
Abstract
Nucleophilic substitution of the halogen in 4-bromo-5-methoxy-3-pyrrolin-2-one (1) is observed by using dimethylamine, azide, phenylmethanethiolate and 2-propanethiolate ions. The reaction of 1 with methoxide ion affords 5,5-dimethoxy-3-pyrrolin-2-one (2). As a general rule, secondary amines react with 1 yielding the respective 4,5-diaminosubstituted 5-pyrrolin-2-one (5). Although the initial reaction of 1 with thiolate ions is the halogen substitution, further reaction with thiolate affords the respective 3-(alkylthio)pyrrolidine-2,5-dione (8) .
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■ A Facile Synthesis of Novel Heterocycle-conjugated Quinoxalines
Yoshihisa Kurasawa,* Shoko Nakamura, Kayano Moriyama, Kumi Suzuki, and Atsushi Takada
*School of Pharmaceutical Sciences, Kitasato University, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
Novel pyrazole- and 1,3,4-oxadiazole-conjugated quinoxalines (5-9) were synthesized selectively from 3-hydrazinocarbonylmethylene-2-oxo-1,2,3,4-tetrahydoquinoxaline (1).
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■ Iodination of Some Diazines and Diazine N-Oxides
Misa V. Jovanovic*
*Department of Chemistry, Southern Methodist University, P.O. Box 750314, Dallas, TX 75275-0314, U.S.A.
Abstract
A number of monosubstituted pyrazines, pyrimidines, and their N-oxides having the electron-donating amino groups were successfully iodinated. Depending on the reaction conditions, the 3-substituted pyrazine 1-oxides having a bulky dialkylamino group yielded the 6-iodo and 2,6-diiodopyrazine N-oxide derivatives together with some deoxygenated products. The mechanism with supportive evidence was presented to account for these chemical transformations.
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■ p-Toluensulfonic Acid and Cation Exchange Resin in Aprotic Solvent: Valuable Catalysts for Fischer Indolization
Yasuoki Murakami,* Yuusaku Yokoyama, Tomoko Miura, Hiroko Hirasawa, Yuuko Kamimura, and Miyoko Izaki
*School of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan
Abstract
p-Toluenesulfonic acid and cation exchange resin (Amberlyst-15) in aprotic solvent were found to serve as a good catalyst for Fischer indolization in many cases. With this condition ethyl indole-2-carboxylate was prepared more conveniently in better yield than by previous methods.
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■ Formation of Anomalous Products in tne Leuckart Reaction of the 2-Bromo-4,5-dimethyoxybrnzyl 2-Hydroxy-3,4-dimethoxyphenyl Ketone
Esther Domínguez,* Esther Lete, M. Jesús Villa, and Carmen Iriondo
*Departamento de Física Aplicada, Facultad de Ciencias, Universidad del País Vasco, Apartado 450, 01080 Vitoria-Gasteiza, Spain
Abstract
The Leuckart reaction of the 2-bromo-4,5-dimethoxybenzyl 2-hydroxy-3,4-dimethoxyphenyl ketone (2) afforded, not the expected amine, but three anomalous products: the stilbene (3), the isoflavone (4) and the pyrimidine (5). Their structures have been established on the basis of their spectral data.
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■ A Facile Route to Fused Heterocycles with an Exocyclic by Intramolecular Nucleophilic Aminations to Acetylene
Tadashi Sasaki* and Ikuo Shimizu
*Institute of Applied Organic Chemistry, Faculty of Engineering, Nagoya University, Chikusa, Nagoya, Aichi 464-8601, Japan
Abstract
The novel method for synthesis of fused heterocycles with an exocyclic methylene was investigated. The terminally acetylene-substituted heterocycles 3a-c and 6a-d were converted to the fused heterocycles with an exocyclic methylene 4a-c and 7a-d by intramolecular nucleophilic amination to acetylene part.
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■ A Convenient Synthesis of Pyrimido[5,4-g]pteridinetetrones
Yoshihisa Okamoto,* Kuniyoshi Ogura, Yoshihisa Kurasawa, and Toshio Kinoshita
*Center for Natural Sciences, Kitasato University, 1-15-1, Kitasato, Sagamihara, Kanagawa 228-8555, Japan
Abstract
The oxidation reactions of 5,6-diaminouracil derivatives with ferric chloride gave pyrimido[5,4-g]pteridinetetrones in good yield.
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■ Syntheses of 2-Alkyl-3-(4-dialkylaminoalkoxy-benzoyl)-thieno[3,2-c]pyridines
Daniel Fréhel,* Robert Boigegrain, and Jean-Pierre Maffrand
*Linge Hémobiologie, Sanofi Recherche, 195 route d’Espagne, 31036 Toulouse, France
Abstract
This paper deals with the syntheses of thieno(3,2-c)pyridinic isosteres 4 of two potent anti-anginal and/or antiarrythmic agents : amiodarone 1 and butoprozin 2. The corresponding tetrahydrogenated analogs are also synthesized.
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■ Further Studies on the Colorination Reaction of 7-Substituted Theophylline Derivativces
Tetsuji Kametani,* Setsu Saitou, and Toshio Honda
*Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
The colorination reaction of 7-substituted theophylline derivatives was described.