Regular Issue

Vol. 34, No. 2, 1992

18 data found. 1 - 18 listed
Communication | Regular issue | Vol 34, No. 2, 1992, pp.219-223
Published online:
DOI: 10.3987/COM-91-5803
Chemistry of Indoles Carrying Basic Functions. Part II. Synthesis of 4-Substituted Cyclohept[c.d]indoles. A New Entry into the Ring System

István Moldval, Csaba Szántay Jr., and Csaba Szántay*

*Central Research Institute for Chemistry, Hungarian Academy of Sciences, H-1025 Budapest, P.O.Box 17, Hungary

Abstract

Cyclohept[c,d]indoles (7a), (7b), (12) were synthesized starting from 4-iodoindole-3-carboxaldehydes (3a) and (3b).

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Communication | Regular issue | Vol 34, No. 2, 1992, pp.225-228
Published online:
DOI: 10.3987/COM-91-5895
Synthesis of 6-Alkylamino-3-pyridazinecarboxylic Acid Derivatives from Methyl 6-Chloro-3-pyridazinecarboxylate

Shoetsu Konno, Mataichi Sagi, Futoshi Siga, and Hiroshi Yamanaka*

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, Japan

Abstract

The synthesis of methyl 6-alkylamino-3-pyridazinecarboxylates (4a-c) was accomplished by the following reaction sequence. On treatment of methyl 6-chloro-3-pyridazinecarboxylate (1) with methanolic ammonia, 6-chloro-3-pyridazinecarboxamide (5) was precipitated almost quantitatively, which reacted with primary alkylamines to give the corresponding 6-alkylamino-3-pyridazinecarboxamide (6a-c). These products were smoothly converted into the methyl esters (4a-c) by treatment with methanol in the presence of boron trifluoride etherate. The reaction of 1 with butylamine in THF gave a complicated mixture in which N-butyl-6-chloro-3-pyridazinecarboxamide (2), N-butyl-6-butylamino-3-pyridazinecalboxamide (3), 4b, and 1 were involved.

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Communication | Regular issue | Vol 34, No. 2, 1992, pp.229-236
Published online:
DOI: 10.3987/COM-91-9515
7-Deazaguanosine: Phosphoramidite and Phosphonate Building Blocks for Solid-Phase Oligoribonucleotide Synthesis

Frank Seela* and Karin Mersmann

*Laboratorium für Organische and Bioorganische Chemie, Fachbereich Biologie/Chemie, Universität Osnabrück, Barbarastr. 7, D-4500 Osnabrück, Germany

Abstract

The synthesis of oligoribonucleotide building blocks (phosphonates and phosphoramidites) of 7-deazaguanosine (2-amino-7-(β-D-ribofuranosyl)-7H-pyrrolo[2,3-d]pyrimidin-4(3H)-one, 1) is described. Silylation of the 2'-hydroxy group of 7-deaza-N2-isobutyryl-5'-O-(4-monomethoxytrityl)guanosine (5) was studied with regard to the 2'-selectivity. Best results were obtained with triisopropylsilyl chloride/AgNO3. The 2'-O-protected intermediates (6a and 6b) were converted into the phosphonates (3a, b) or methylphosphoramidites (4a, b), which were successfully used for solid-phase oligoribonucleotide synthesis of (c7G-C)3 (9).

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Communication | Regular issue | Vol 34, No. 2, 1992, pp.237-240
Published online:
DOI: 10.3987/COM-91-5921
A Facile Synthesis of Fluorine-containing Bicyclic Oxadiazines

Yasuhiro Kamitori, Masaru Hojo,* Ryoichi Masuda, Toru Numai, Katsumasa Yamamoto, and Isao Nakamura

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

Abstract

By treatment with trifluoroacetic acid fluorine-containing bicyclic oxadiazines (3) could be synthesized in satisfactory yields from hydrazones (1) which were prepared from aldehyde methylhydrazones bearing N-allylic group and trifluoroacetic anhydride.

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Communication | Regular issue | Vol 34, No. 2, 1992, pp.241-245
Published online:
DOI: 10.3987/COM-91-5925
Preparation of (6R)- and (6S)-(1R,4R)-6-Methyl-2-(p-toluenesulfonyl)-5-phenylmethyl-2,5-diazabicyclo[2.2.1]heptanes, Intermediates in a Synthesis of New Quinolones

Philippe Remuzon,* Daniel Bouzard, Christian Dussy, Jean-Pierre Jacquet, and Massoud Massoudi

*Bristol-Myers Squibb Pharmaceutical Research Institute, BP 62, Lognes, 77422 Marne-la-Vallée Cedex 2, France

Abstract

An efficient chiral synthesis of both diastereoisomers (2a) and (2b) was performed using trans-4-hydroxy-L-proline as starting material. These bridged piperazines were used in the preparation of quinolones.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.247-258
Published online:
DOI: 10.3987/COM-90-5612
5,12-Di(1-alkyl)thioquinanthrenediinium Bis-salts and 1-Alkyl-3-alkylthio-1,4-dihydro-4-thiooxoquinolines

Andrzej Maslankiewicz* and Andrzej Zieba

*Department of Organic Chemistry, Silesian School of Medicine, ul. Jagiellonska Str. 4, 41-200 Sosnowiec, Poland

Abstract

The preparation of 5,12-di(1-alkyl)thioquinanthrenediinium bis-salts and their transformation into 1-alkyl-3-alkylthio-1,4-dihydro-4-thiooxoquinolines are described.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.259-264
Published online:
DOI: 10.3987/COM-91-5680
Elecrophilic Substitution of Indoles: Part XI. Lewis Acid Induced Reaction of Skatole with Bezil

Asima Chatterjee,* Ratna Chakrabarti, Biswanath Das, Sanchayita Kanrar, Julie Banerji, Herbert Budzikiewicz, Alain Neuman, and Thierry Prangé

*Department of Pure Chemistry, University College of Science, 92 Acharya Prafulla Chandra Road, Calcutta-700009, India

Abstract

The electrophilic substitution of 3-methylindole with benzil in the presence of BF3·Et2O resulted in a novel heterocyclic system incorporating a stable boron difluoride chelate. The structure was established from spectral analysis (1H-, 13C-, 11B-, 19F-nmr) and X-ray crystallographic analysis.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.265-272
Published online:
DOI: 10.3987/COM-91-5890
Synthesis of 2',3'-Dideoxy-D-erythro-hex-2'-enopyranosyl Nucleosides from 5-Aminouracils and 3,4,6-Tri-O-acetyl-D-glucal

Henrik Pedersen, Erik B. Pedersen,* and Carsten M. Nielsen

*Department of Chemistry, Odense University, DK-5230 Odense M, Denmark

Abstract

Condensation of silylated N,N-disubstituted aminouracils (4) and 3,4,6-tri-O-acetyl-D-glucal (3) in the presence of TMS triflate as catalyst gave anomeric mixtures of 2',3'-dideoxy-D-erythro-hex-2'-enopyranosylnucleosides (5) and (6). The pure β- and α-anomers were separated by chromatography and deprotected with a saturated solution of ammonia in methanol to give 1-(2',3'-dideoxy-β-D-erythro-hex-2-enopyranosyl)-5-aminouracils (7) and their corresponding α-anomers (8), respectively. The anomeric configurations of these nucleosides were assigned by nmr analysis of the dihydro derivatives 9 and 10 obtained by hydrogeneration of 7a and 8a, respectively. No significant activity against HIV-1 was found.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.273-291
Published online:
DOI: 10.3987/COM-91-5899
Synthesis and Fluorescent Properties of New Heterobifunctional Fluorescent Probes

Thierry Besson, Benoit Joseph, Pascale Moreau, Marie-Claude Viaud, Gérard Coudert, and Gérald Guillaumet*

*Laboratoire de Chimie Bioorganique et Analytique, URA-CNRS n° 499, Université d'Orléans, BP 6759, 45067 Orléans Cedex 2, France

Abstract

Heterobifunctional fluorescent molecules possessing the same fluorescent properties as their monofunctional parent compounds are investigated. Two different functions of these probes do not alter their lasing properties and allow many potential applications in cellular biochemistry. This paper investigates two families of compounds derived from carbazole and coumarin. The synthesis and spectral properties of these probes are described.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.293-301
Published online:
DOI: 10.3987/COM-91-5900
Study of the Asymmetric Induction of the 1,3-Dipolar Cycloaddition of Chiral Azomethine Ylides with Unactivated Double Bonds

Guillermo Negron, Georges Roussi,* and Jidong Zhang

*Institut de Chimie des Substances Naturelles, C.N.R.S., 91198 Gif-sur-Yvette Cedex, France

Abstract

The asymmetric induction of the 1,3-dipolar cycloaddition reaction between nonstabilized azomethine ylides generated by deprotonation of the corresponding tertiary amine N-oxides (1a-f) with a base and various unactivated olefins (2a-c) or dienes (2d-e) has been studied. The results show that an important induction can be reached with valinol derived N-oxide (1f). The elimination of the chiral substituent in 3-phenyl-N-(1-hydroxymethyl-propyl)pyrrolidine (8b) allowed to determine the absolute configuration of the major enantiomer (12b) in accordance with the proposed transition state.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.303-314
Published online:
DOI: 10.3987/COM-91-5913
The [2-(Trimethylsilyl)ethoxy]methyl Function as a Suitable N-1 Protecting Group in Lithiation Reactions with Pyrazoles and 1,2,4-Triazoles

Natalie Fugina, Wolfgang Holzer,* and Michael Wasicky

*Institute of Pharmaceutical Chemistry, University of Vienna, Währinger Strasse 10, A-1090 Vienna, Austria

Abstract

Metallation of 1-[2-(trimethylsilyl)ethoxy]methyl-1H-pyrazole or 1-[2-(trimethylsilyl)ethoxy]methyl-1H-1,2,4-triazole, respectively, with one equivalent of n-BuLi followed by reaction with appropriate electrophiles leads to 5-substituted 1-[2-(trimethylsilyl)ethoxy]methyl-1H-pyrazoles and 5-substituted 1-[2-(trimethylsilyl)ethoxy]methyl-1H-1,2,4-triazoles. Deprotection can be achieved either by heating with aqueous ethanolic HCl or by treatment with anhydrous tetrabutylammonium fluoride.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.315-320
Published online:
DOI: 10.3987/COM-91-5917
Oxazolones. Part VI. Reaction of 5(4H)-Oxazolones with Nitrile Imines: Synthesis of 1H-1,2,4-Triazoles through [3+2] Cycloaddition

Maria Luisa Gelmi,* Donato Pocar, and Raul Riva

*Istituto di Chimica Organica, Facoltà di Farmacia, Università di Milano, Via Venezian 21, 20133 Milano, Italy

Abstract

5(4H)-Oxazolones (1) react as dipolarophiles in [3+2] cycloaddition with nitrile imines generated from tetrazoles (2) in refluxing anisole affording two 1H-1,2,4-triazole derivatives (3) and diarylethylenes (4).

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.321-339
Published online:
DOI: 10.3987/COM-91-5922
Syntheses of (±)-Z-Geissoschizol, (±)-3-epi-Z-Geissoschizol, (±)-Corynantheidol, (±)-Dihydrocorynantheol, (±)-3-epi-Dihydrocorynantheol and the Corresponding Corynan-17-oic Acid Methyl Esters

Mauri Lounasmaa,* Reija Jokela, Birgit Tirkkonen, Jari Miettinen, and Minna Halonen

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

Abstract

The utility of the Claisen rearrangement using carefully separated, diastereoisomerric allylic alcohols (1a) and (1b) in the preparation of (±)-Z-geissoschizol (4a), (±)-3-epi-Z-geissoschizol (4b), (±)-corynantheidol (7a), (±)-dihydrocorynantheol (8a), (±)-3-epi-dihydrocorynantheol (8b) and the corresponding corynan-17-oic acid methyl esters (3a, 3b, 5a, 6a, and 6b) is shown. Special attention is paid to the stereochemical outcome of catalytic (PtO2) hydrogenation of the C(20) Z-ethylidene side chain.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.341-347
Published online:
DOI: 10.3987/COM-91-5926
Synthesis and Attempted [4+2] Cycloaddition Reaction of 2,4,6-Tris(phenylseleno and aryltelluro)-1,3,5-triazines with Diethyl Acetylenedicarboxylate

Hiroyuki Tani,* Tokuo Inamasu, and Hitomi Suzuki*

*Advanced Instrumentation Center for Chemical Analysis, Ehime University, Bunkyo-cho 2-5, Matsuyama 790, Japan

Abstract

2,4,6-Tris(phenylseleno and aryltelluro)-1,3,5-triazines were synthesized by the reaction of 2,4,6-trichloro-1,3,5-triazine with corresponding arylchalcogenide anions. These 2,4,6-tris(arylchalcogeno)-1,3,5-triazines failed to undergo the Diels-Alder reaction with diethyl acetylenedicarboxylate.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.349-355
Published online:
DOI: 10.3987/COM-91-5930
Use of Chiral Amidals in the Synthesis of 6-Methylperihydropyrimidin-4-ones, Protected Form of β-Amino Acids

Rosa Amoroso, Giuliana Cardillo,* and Claudia Tomasini

*Dipartimento di Chimica "G. Giamician", Università di Bologna, Centro per lo Studio della Fisica delle Macromolecole, via Selmi 2, 40126 Bologna, Italy

Abstract

The synthesis of 6-methylperihydropyrimidin-4-ones (7a and 7b) is described by mercury cyclization of the β,γ-unsaturated amidal (3). After reduction of the intermediate organomercury compound (6) and separation of the diastereomeric mixture, the perihydropyrimidin-4-ones (7a and 7b) have been obtained. Their structure has been fully characterized by means of 1H nmr spectroscopy and, after acid hydrolysis, the 3-aminobutyric acids (8a and 8b) have been obtained.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.357-362
Published online:
DOI: 10.3987/COM-91-5931
Amidoalkylation of Pyrazine-2,3-dicarbonitrile by the Radical Generated from N-Alkanoylanilinoalkanoic Acid

Masaru Tada,* Reiko Furuse, and Hiroko Kashima

*Department of Chemistry, School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169, Japan

Abstract

N-Alkanoylanilinoacetic acid and 2-N-alkanoylanilinopropionic acid gave N-alkanoylanilinomethyl radical and 1-N-alkanoylanilinoethyl radical respectively by the peroxodisulfate oxidation catalized by silver ion. The former radical reacts with pyrazine-2,3-dicarbonitrile to give both monosubstitution product (6) and disubstitution product (7), whereas the latter radical gives only monosubstitution product due to the steric hindrance for the second radical substitution.

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Paper | Regular issue | Vol 34, No. 2, 1992, pp.363-367
Published online:
DOI: 10.3987/COM-91-5933
Synthesis of (2S,4S)-2-Hydroxy-4-hydroxymethyl-4-butanolide, a Hunger Substance

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

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

Abstract

(2S,4S)-2-Hydroxy-4-hydroxymethyl-4-butanolide (1a), which is a hunger substance, was synthesized stereoselectively starting from D-γ-ribono-1,4-lactone (2).

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Review | Regular issue | Vol 34, No. 2, 1992, pp.369-385
Published online:
DOI: 10.3987/REV-91-437
Four-membered Heterocycles Containing One Phosphorus and One Other Heteroatom

Kamyar Afarinkia

*Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, U.S.A.

Abstract

Syntheses and properties of oxaphosphetanes, thiaphosphetanes, azaphosphetidines and diphosphetanes are reviewed.

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18 data found. 1 - 18 listed