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. 12, No. 2, 1979
Published online:
■ Photocyclization and Photooxygenation of 1,3,4,5-Tetraarylimidazolin-2-ones
Otohiko Tsuge,* Koji Oe, and Hisataka Inoue
*Research Institute of Industrial Science, Faculty of Engineering, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan
Abstract
Irradiation of 1,3,4,5-tetraarylimidazolin-2-ones in benzene, under nitrogen, with or without iodine gave the corresponding phenanthroimidazolinones. In the presence of oxygen, however, the imidazolinone was photochemically converted to the corresponding benzanilide, N-benzoyl-N ,N’-diphenylbenzamidine and p-benzoylphenyl isocyanate, besides the phenanthroimidazolinone. On the other hand, the dye-sensitized photooxygenation afforded the benzanilide, amidine, N,N’-dibenzoyl-N,N’-diphenylurea, and/or 1,4-diaza-1,3-butadiene derivative, whose yields depended on the nature of substituents of the imidazolinone and of the solvent employed. Mechanistic consideration of the photooxygenation was also described.
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■ A Facile Method for the Preparation of 4-Nitropyridine and -quinoline Derivatives: Reduction of Aromatic Amine N-Oxides with Trimethylphosphite under Irradiation
Chikara Kaneko,* Atsushi Yamamoto, and Michiko Gomi
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
Irradiation (> 300 nm) of pyridine and quinoline 1-oxides having a nitro group at the 4-position in dichloromethane containing trimethylphosphite of relatively high concentration (> 10-2mol/l) resulted in an almost quantitative formation of the deoxygenated products.
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■ Cycloaddition Reactions of Diphenylketene with 1-Aza-1,3-diene and Conjugated Sulfilimines
Masanori Sakamoto,* Kyoko Miyazawa, Keiko Kuwabara, and Yoshio Tomimatsu
*Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan
Abstract
The cycloaddition reactions of diphenylketene (I) with several azadienes have been examined. 2-Styrylthiazoline (IIa-c) and I generally underwent a 4+2 cycloaddition to give thiazolo[3,2-a]pyridines (IIIa-c). On the other hand, reaction of I with 2-styrylquinoline and 2-styrylpyridine gave rise to a 2+2+2 cycloaddition products (Va, b), respectively. Similar reaction of I with 6-styrylphenanthridine gave pyrido[1,2-f]phenanthridine (VII) and a lactone (Vc).
The orientation of the addition products of I with sulfilimines (VIII, XI, XII) which we reported in our previous paper was the error and the reverse.
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■ A Synthesis of 3-Hydroxyiminoacryl-4-quinazolines and Transformation into 1,2,4-Oxadiazoles
Katsuhiko Nagahara* and Atsushi Takada
*School of Pharmaceutical Sciences, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
Treatment of N-hydroxyiminobenzyl-2-aminobenzamides (I) with ortho esters afforded the corresponding 2-alkyl-3-hydroxyiminoacyl-4-quinazolones (II) and 3,5-diaryl-1,2,4-oxadiazoles (III), respectively. Furthermore, treatment of II with ethanolic hydrochloric acid caused the ring transformation to give the corresponding III.
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■ An Azabycyclo[3.3.1]nonanone Apprpach to Tecoma Alkaloids: A Stereoselective Synthesis of (±)-7-Demethyltecomanine
Takefumi Momose,* Masahiko Kinoshita, and Takeshi Imanishi
*Faculty of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Toyonaka, Osaka 560-0043, Japan
Abstract
A stereoselective synthesis of (±)-7-demethyltecomanine (2) via a 3-azabicyclo[3.3.1]nonane precursor (4) which has the same configuration at the 3,5-position on the piperidine ring as that for tecomanine (1) is described.
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■ Biotransformation of Some 2-Methylpapaverinium Derivatives with Rat Liver Enzymes in Vitro
Dana Walterová,* Alice Nemecková, Vladimír Preininger, Vilím Simánek, and Ladislav Dolejs
*Institute of Medical Chemistry, Palacky University, 3, Hnevotínská, 775 15 Olomouc, Czech Republic
Abstract
2-Methyl-3,4-dihydropapaverinium derivatives (1-3) and 2-methylpapaverinium chloride (4) have been converted into the corresponding isoquinolones and carbonyl compounds by incubation with rat liver preparations. The role of pseudobase formation in this biotransformation is discussed.
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■ Reaction of Citral with Homophthalic Anhydrides
Suneel Y. Dike and Jaysukhlal R. Merchant*
*Department of Organic Chemistry, Institute of Science, 15, Madam Cama Road, Bombay-400 032, India
Abstract
Syntheses of 2-methyl-2-(4-methylpent-3-enyl)-5-(2-carboxyphenyl)-pyran-6-one from homophthalic acid and anhydrides with citral is described.
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■ The Reaction of 4-Hydroxycoumarin with Acetic Anhydride and Pyridine
V. K. Ahluwalia,* Devendra Kumar, and Suman Mehta
*Department of Chemistry, University of Delhi, Delhi-110 007, India
Abstract
The reaction of 4-hydroxycoumarin (I) with acetic anhydride - pyridine afforded 4-acetoxy-3-(N-acetyl-1’,2’-dihydro-2’-pyridyl)coumarin (III) in contrast to the expected 4-acetoxycoumarin (IV). The structure of compound has been established spectroscopically.
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■ Reactions of Azepine and Diasepine Derivatives with Chlorosilanes in the Presence of Magnesium: 4,5-Double Addition Reactions to Azepine Derivatives
Katsuhiro Saito* and Kensuke Takahashi
*Faculty of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
Abstract
The reactions of 1-ethoxycarbonyl-1H-azepine (1) and chlorosilanes (Xa-c) in HMPA in the presence of magnesium afforded 1:2 adducts, trans-4,5-disubstituted-4,5-dihydroazepines (2a-c), which upon heating gave siloxane derivatives (3a-b) almost quantitatively. In the same reactions with 1-ethoxycarbonyl-1H-1,2-diazepine (8), a nitryl compound (9) was obtained. The dihydroazepines and the nitryl compound are considered to be formed via radical anions 5 and 10, respectively.
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■ Absorption Spectra of Phytoxanthones
M. Afzal,* Jassim M. Al-Hassan, and Farida N. Al-Masad
*Biochemistry Department, Kuwait University, Safat 13060 P.O. Box 5969, Kuwait
Abstract
The Ultraviolet Absorption Spectra of Phytoxanthones are reviewed.