Regular Issue

Vol. 34, No. 10, 1992

12 data found. 1 - 12 listed
Communication | Regular issue | Vol 34, No. 10, 1992, pp. 1877 - 1884
Published online:
DOI: 10.3987/COM-92-6140
The Chemistry of 1-Hydroxyindole Derivatives: Nucleophilic Substitution Reactions on Indole Nucleus

Masanori Somei,* Toshiya Kawasaki, Yoshikazu Fukui, Fumio Yamada, Tetsuya Kobayashi, Harumi Aoyama, and Daisuke Shinmyo

*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920, Japan


Nucleophilic substitution reactions were newly found to occur generally in the chemistry of 1-hydroxyindole derivatives. Its application to the synthesis of a phytoalexin, brassicanal A, is reported.

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1885 - 1895
Published online:
DOI: 10.3987/COM-92-6078
Synthesis and Stereochemistry of Tropane 6-Spiro-hydantoins

Mercedes Villacampa,* Manuel Martínez, Gregorio González-Trigo, and Mónica M. Söllhuber

*Departamento de Química Orgánica y Farmacéutica, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain


The synthesis of several representatives of the previously unknown N-alkyl-nortropane-6-spirohydantoin ring system by Bucherer-Bergs reaction of 8-alkyl-8-azabicyclo[3.2.1]octan-6-ones is described. 3-Oxo derivatives of the parent structure were also prepared. The stereochemical outcome of the Bucherer-Bergs reaction is discussed on the basis of 1H-nmr and 13C-nmr data.

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1897 - 1904
Published online:
DOI: 10.3987/COM-92-6095
The Serendipitous Formation of an Unusual Methyl N’-Cyano-N-[5-methylthio-1,2,4-triazol-3-ylidene]carbamimidothioate and Subsequent Reactions

Dennis J. Hlasta,* Malcolm R. Bell, Rudolf K. Kullnig, and Joseph R. Wetzel

*Departments of Medical Chemistry and Molecular Characterization, Sterling Winthrop Pharmaceuticals Research Division, 81 Columbia Turnpike, Rensselaer, New York 12144, U.S.A.


Dimethyl cyanocarbamimidodithioate (1) (2 equivalents) reacts with 1,2-dimethylhydrazine to afford the cyclic derivative, methyl N’-cyano-N-(5-methylthio-1,2,4-triazol-3-ylidene)carbamimidothioate (5), instead of an expected acyclic derivative. The triazole (5) undergoes di-addition-elimination reactons with primary aliphatic amines to afford N’’-cyano-N-(5-amino-1,2,4-triazol-3-ylidene)guanidines (6).

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1905 - 1916
Published online:
DOI: 10.3987/COM-92-6101
A Synthesis of 1,2,3,4-Tetrahydro-1,6-naphthyridines

Pedro J. Victory,* Jordi Teixidó, and José I. Borrell

*CETS Institut Químic de Sarrià, (Universitat Ramon Llull), Departament de Química Orgànica, E-08017 Barcelona, Spain


8-Cyano-3,4-dihydro-1,6-naphthyridin-2(1H)-ones were obtained by nucleophilic substitution of the methoxyl group of 5-cyano-3,4-dihydro-6-methoxy-2(1H)-pyridones (5a-d) by malononitrile or cyanoacetamide followed by cyclization in acidic or basic medium.

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1917 - 1926
Published online:
DOI: 10.3987/COM-92-6108
Direct Amination. Part 4. Reactions of Indoles with Primary Aromatic Amines and Iodosobenzene Diacetate

Liberato Cardellini, Lucedio Greci,* Eziana Maurelli, Mario Orena, Pierluigi Stipa, and Giorgio Tosi

*Dipartimento di Scienze dei Materiali e della Terra, Università, Via Brecce Bianche, I-60131 Ancona, Italy


Indole, 2-methylindole, 2-phenylindole, and primary aromatic amines react with iodosobenzene diacetate leading both to 2-arylamino-3-arylimino-3H-indole in the case of indole and 2-methylindole, and to 2-phenyl-3-arylimino-3H-indole in the case of 2-phenylindole. The reaction is believed to proceed through the formation of a nitrenium ion formed by the interaction of iodosobenzene diacetate and primary aromatic amines and the mechanism is supported by experimental evidences. The methyl elimination from 2-methylindole is explained on the basis of the isolation of the possible intermediate and the formation of an aminal, whose decomposition leads to the reaction products. The intermediate aminal is proposed on the basis of the bis-(2-methylindol-3-yl)methane formation.

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1927 - 1934
Published online:
DOI: 10.3987/COM-92-6111
A Facile and Convenient Synthetic Method for Fluorine-containing Pyridines, 1,2-Dihydropyridines, and 2-Pyridones

Etsuji Okada, Ryoichi Masuda, and Masaru Hojo*

*Department of Industrial Chemistry, Faculty of Engineering, Kobe University, Kobe 657, Japan


1-Ethylthio- and 1-dimethylamino-4,4-bis(trifluoroacetyl)-1,3-butadienes (1, 2) reacted easily with aqueous ammonia and various primary amines under mild conditions to afford selectively the corresponding fluorine-containing pyridines (3), 1,2-dihydropyridines (4), and 2-pyridones (5) in excellent yields.

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1935 - 1947
Published online:
DOI: 10.3987/COM-92-6112
Synthesis of 1,6:3,4-Dianhydro-β-D-talopyranose from Levoglucosenone: Epoxidation of Olefin via trans-Iodoacetoxylation

Katsuya Matsumoto,* Takashi Ebata,* Koshi Koseki, Koji Okano, Hiroshi Kawakami, and Hajime Matsushita

*Life Science Research Laboratory, Japan Tobacco Inc., 6-2, Umegaoka, Midori-ku, Yokohama, Kanagawa 227, Japan


Levoglucosenone (1,6-anhydro-3,4-dideoxy-β-D-glycero-hex-3-enopyranos-2-ulose, 1) was converted to give 1,6:3,4-dianhydro-β-D-talopyranose (8) in good yield through stereoselective trans-iodoacetoxylation followed by basic hydrolysis.

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1949 - 1956
Published online:
DOI: 10.3987/COM-92-6119
NOE Difference Spectroscopy Applied in Stereochemical Investigations of Two Diastereomeric Indoloquinolizidine Alcohols, Significant in the Preparation of Geissoschizine-Type Compounds

Reija Jokela

*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, SF-02150 Espoo, Finland


Complete 1H-nmr data were recorded for indoloquinolizidine alcohols (2a) and (2b), significant intermediates in the preparation of geissoschizine-type compounds, and for their benzoyl derivatives (3a) and (3b). The stereochemistry was deduced from NOE measurements.

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1957 - 1964
Published online:
DOI: 10.3987/COM-92-6120
The Structures of Two Isomeric N-Formates from 3-O-Acetylsolasodine

Genjiro Kusano,* Chika Sekimoto, Mayumi Abe, Yasuko In, Hirofumi Ohishi, Toshimasa Ishida, and Norio Aimi

*Osaka University of Pharmaceutical Sciences, 2-10-65 Kawai, Matsubara, Osaka 580, Japan


The structures of two isomeric N-formates, I (1) and II (2), prepared from O-acetylsolasodine, were determined by X-ray crystalographic analyses, and the isomerism between them was shown to be caused by the epimerization at C-22 during the formylation.

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Paper | Regular issue | Vol 34, No. 10, 1992, pp. 1965 - 1972
Published online:
DOI: 10.3987/COM-92-6136
Isolation of the Intermediates and Improved Synthesis of Pyrido[1’,2’:1,2]imidazo[4,5-b]pyrazines and -quinoxalines

Akira Katoh,* Shuhei Ueda, Junko Ohkanda, Mutsumi Hirota, Hiroshi Komine, and Keiryo Mitsuhashi

*Department of Industrial Chemistry, Faculty of Engineering, Seikei University, Musashino-shi, Tokyo 180, Japan


2-(Pyrid-2’-yl)amino-3-chloro-5,6-dicyanopyrazines (IIa, IId, and IIe) and 2-(pyrid-2’-yl)amino-3-chloro-6-nitroquinoxalines (Va-c) were isolated for the first time in the course of the reaction of 2,3-dichloro-5,6-dicyanopyrazine (I) and 2,3-dichloro-6-nitroquinoxaline (IVa), respectively, with 2-aminopyridines. Furthermore, the yield of pyrido[1’,2’:1,2]imidazo[4,5-b]quinoxalines was remarkably improved due to the modification of the reaction conditions.

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Review | Regular issue | Vol 34, No. 10, 1992, pp. 1973 - 2002
Published online:
DOI: 10.3987/REV-92-440
Alkaloid N-Oxides

Angelo Albini

*Institute of Organic Chemistry, The University, V. P. Giuria 7, 10125 Torino, Italy


More than 200 aliphatic and aromatic N-oxides have been individuated among natural-occurring alkaloids. The structures of these compounds as well as the role that N-oxides have in the synthesis and the chemical modification of alkaloids are reviewed.

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Review | Regular issue | Vol 34, No. 10, 1992, pp. 2003 - 2027
Published online:
DOI: 10.3987/REV-92-445
Synthesis of Mixed Thiophene-Pyrrole Heterocycles

Renée E. Niziurski-Mann and Michael P. Cava*

*Department of Chemistry, The University of Alabama, Box 870336, Tuscaloosa, AL 35487-0336, U. S. A.


The synthesis of mixed thiophene-pyrrole heterocycles has been reviewed. The systems under consideration are various isomeric thienylpyrroles as well as tricyclic analogs containing non-condensed combinations of two or three pyrrole and thiophene units.

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12 data found. 1 - 12 listed