Regular Issue

Vol. 32, No. 5, 1991

21 data found. 1 - 21 listed
Communication | Regular issue | Vol 32, No. 5, 1991, pp.849-853
Published online:
DOI: 10.3987/COM-91-5681
Fischer Reaction of 1-Acetyl-3-oxo-2,3-dihydroindole and 1-(p-Toluenesulfonyloxy)-3-oxo-2,3-dihydroindole

Jean-Yves Mérour* and Laurence Savelon

*Laboratoire de Chimie Bioorganique et Analytique, URA-CNRS N° 499, Université d‘Orléans, BP 6759, Rue de Chartres, 45067 Orleans Cedex 2, France

Abstract

1-(p-toluenesulfonyloxy)-3-oxo-2,3-dihydroindole reacted with phenylhydrazine in acetic acid affording 5-(p-toluenesulfonyloxy)indolo[3,2-b]indole. By contrast 1-acetyl-3-oxo-2,3-dihydroindole in the same experimental conditions afforded 12-aminoindolo[1,2-c]quinazoline.

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Communication | Regular issue | Vol 32, No. 5, 1991, pp.855-857
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DOI: 10.3987/COM-91-5711
Radical Carbamoylation of 1,2,3-Triazinium 2-Dicyanomethylides

Kazuhiro Nagata, Takashi Itoh, Mamiko Okada, Hiroyuki Takahashi, and Akio Ohsawa*

*School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan

Abstract

The nucleophilic radical carbamoylation of 4,6-disubstituted 1,2,3-triazinium 2-dicyanomethylides occurred at their 5-positions followed by the elimination of dicyanomethylene to form 5-substituted 1,2,3-triazines. The reaction did not proceed when parent triazines were adopted as the substrates.

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Communication | Regular issue | Vol 32, No. 5, 1991, pp.859-862
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DOI: 10.3987/COM-91-5718
Synthesis of Dehydrodeoxypodophyllotoxin Cyclic Ether via Allene Intramolecular Cycloaddition Strategy and Evaluation of Its Cytotoxicity

Ken Kanematsu,* Michiko Tsuruoka, Yumiko Takaoka, and Takuma Sasaki

*Institute of Synthetic Organic Chemistry, Faculty of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan

Abstract

The new route to dehydrodeoxypodophyllotoxin cyclic ether (10) has been realized via allene intramolecular Diels-Alder reaction of the propargyl ether (8).

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Communication | Regular issue | Vol 32, No. 5, 1991, pp.863-866
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DOI: 10.3987/COM-91-5724
A Novel Approach to Quaternary Substituted Chiral Cyclobutanes. A Formal Enantioselective Total Synthesis of 1,3-Dioxole Pheromone, (-)-Frontalin

Hideo Nemoto, Toshie Yamada, Hiroki Ishibashi, Junko Takazawa, and Keiichiro Fukumoto*

*Faculty Institute Sciences, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan

Abstract

A novel synthesis of the quaternary substituted chiral cyclobutanone (9) was achieved by the concerted ring expansion of the chiral cyclopropyl epoxide (8) which lead to a formal total synthesis of (-)-frontalin (14).

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Communication | Regular issue | Vol 32, No. 5, 1991, pp.867-871
Published online:
DOI: 10.3987/COM-91-5728
Synthesis of Carbocyclic Oxetanocin Analogues as Potential Anti-HIV Agents. Part 3

Hassane Boumchita, Michel Legraverend,* Jean Guilhem, and Emile Bisagni

*URA 1387, CNRS, Institut Curie, Section de Biologie, Centne Universitaire, Bât. 110-112, Institut Curie, 15 Rue Georges Clemenceau 91405 Orsay, France

Abstract

Two new carbocyclic oxetanocin analogues have been prepared from 1-amino-3-methylenecyclobutane. The results of biological testing against HIV-12 invitro are presented.

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Communication | Regular issue | Vol 32, No. 5, 1991, pp.873-878
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DOI: 10.3987/COM-91-5732
Ergot Alkaloids: The First and Five Step Total Syntheses of (—)- and (+)-6,7-Secoagroclavines, and the Syntheses of (—)- and (+)-6-Nor-6-propyl-6,7-secoagroclavines ((—)- and (+)-KSU 1415)

Kyoko Nakagawa and Masanori Somei*

*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan

Abstract

Simple synthetic method for optically active 4,5-trans-((—)- and (+)-6) and 4,5-cis-5-(2-methyl-1-propen-1-yl)-4-nitro-1,3,4,5-tetrahydrobenz[cd]indoles ((—)- and (+)-7) was developed. Using these chiral common synthetic intermediates, the first total syntheses of (—)- and (+)-6,7-secoagroclavines were achieved in only five steps. Preparations of (—)- and (+)-6-nor-6-propyl-6,7-secoagroclavines ((—)- and (+)-KSU 1415) are also described.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.879-888
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DOI: 10.3987/COM-90-5361
Asymmetric Synthesis XXV. Diastereoselective Synthesis of Indolizidinediol Alkaloid Analogs

Virginie Ratovelomanana, Laurent Vidal, Jacques Royer, and Henri-Philippe Husson*

*Institut de Chimie des Substances Naturelles, C.N.R.S., 1 avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France

Abstract

The asymmetric synthesis of 3-methylindolizidine-1,2-diol, analog of indolizidine-1,2-diol alkaloids, has been achieved from the chiral 2-cyano-6-oxazolopiperidine synthon (1). The synthesis commenced with 1,2 addition of the anion of 1 on crotonaldehyde leading to 8 with enantioselective formation of the firtst hydroxyl group. Epoxidation of the double bond followed by hydrogenolysis of the benzyl appendage led to the amino epoxides (13). Finally the five membered ring construction was accomplished by employing cyclization of 13.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.889-894
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DOI: 10.3987/COM-90-5381
A Facile Synthesis of dl-Sedamine and dl-Allosedamine

Naganori Ozawa,* Setsuko Nakajima, Kyoko Zaoya, Fumiko Hamaguchi, and Tatsuo Nagasaka

*School of Pharmacy, Tokyo College of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan

Abstract

Racemic sedamine and dl-allosedamine were easily synthesized from the intermediate (3) using a cyclic acyliminium salt by the addition-elimination reaction sequence.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.895-900
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DOI: 10.3987/COM-90-5622
Pyridazine Derivatives and Related Compounds Part 5. Pyrazolo[3,4-c]pyridazine: Synthesis and Some Reactions

Ali Deeb,* Besher Bayoumy, Abd El-Naby Essawy, and Rida Fikry

*Department of Chemistry, Faculty of Science, University of Zagazig, Zagazig, Egypt

Abstract

This paper describes the synthesis of three pyrimido[1’,2’: 1,5]pyrazolo[3,4-c]pyridazines (6, 7 and 9) starting from 3-amino[3,4-c]pyridazine (1). Pyrimido[5’,4’:5,6]pyrimido[1’,2’:1,5]pyrazolo[3,4-c]pyridazine derivatives (8) was obtained by condensing 7a with formamide. Reactions of 1 with acetic anhydride, benzoyl chloride, phenacyl bromide and 4-chlorophenacyl bromide gave 3-substituted amino derivatives.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.901-905
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DOI: 10.3987/COM-90-5623
Pyridazine Derivatives and Related Compound Part 6. Synthesis of Triazolo[3’,4’:5,1]pyrazolo[3,4-c]pyridazine, Pyrido[2’,1’:3,2][1,2,4]triazolo[5’,1’:5,1]pyrazolo[3,4-c]pyridazine and Naphtho[2,1-e]pyridazino[3’,4’:3,4]pyrazolo[5,1-c][1,2,4]triazine Derivatives

Ali Deeb,* Besher Bayoumy, Ahmed Hataba, and Rida Fikry

*Department of Chemistry, Faculty of Science, University of Zagazig, Zagazig, Egypt

Abstract

1,2,4-Triazolo[3’,4’:5,1]pyrazolo[3,4-c]pyridazine, pyrido[2’,1’:3,2][1,2,4]triazolo[5’,1’:5,1]pyrazolo[3,4-c]pyridazine, naphtho[2,1-e]pyridazino[3’,4’:3,4]pyrazolo[5,1-c][1,2,4]triazine and pyridazino[3’,4’:3,4]pyrazolo[5,1-c][1,2,4]triazin-4(1H)-one were synthesized from 3-amino-1H-pyrazolo[3,4-c]pyridazine.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.907-914
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DOI: 10.3987/COM-90-5636
Synthesis of 1,3-Diaryl-1,3-dihydro-4,5-dioxo-2-thioxofuro[2,3-d]pyrimidines and 1,3-Diaryl-1,3-dihydro-2-thioxo-5-(thiazol-4-l)-2H,5H-pyrimidine-4,6-diones

Vinod Kumar Ahluwalia,* Rashmi Sharma, Chandra Has Khanduri, M. Kaur, and Charu Gupta

*Department of Chemistry, University of Delhi, Delhi-110 007, India

Abstract

The reaction of thiobarbituric acids with chloroacetyl chloride in presence of triethylamine afforded 5-chloroacetyl derivatives which on cyclisation with ethanolic sodium acetate gave the corresponding furo[2,3-d]pyrimidines. Further the 5-chloroacetyl derivative on reaction with ammonium dithiocarbamate and thioacetamide gave 1,3-diaryl-1,3-dihydro-2-thioxo-5-(thiazol-4-yl)-2H,5H-pyrimidine-4,6-diones.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.915-922
Published online:
DOI: 10.3987/COM-90-5644
Regiochemical Study in the Diels-Alder Reaction of 2-Azaanthraquinon-3-ones

Boufelja Bouammali, Félix Pautet, and Houda Fillion*

*Laboratoire de Chimie Organique Institut des Sciences, Pharmaceutiques et Biologiques, Université Claude Bernard, Lyon I, 8 avenue Rockfeller, 69373 Lyon Cedex 08, France

Abstract

The regiochemistry of the Diels-Alder reaction between 2-aza-1,3-butadienes (1) and naphthoquinones (2) (R = OH or OAc) is investigated.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.923-936
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DOI: 10.3987/COM-91-5682
First Synthesis of (+)-Septorine

Akihiro Ohta,* Akihiko Kojima, Terumi Saito, Kayoko Kobayashi, Hideo Saito, Koichi Wakabayashi, Susumu Honma, Chiseko Sakuma, and Yutaka Aoyagi

*Tokyo College of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan

Abstract

(+)-Septorine, a metabolite of Septoria nodorum, was synthesized via alanyl-isoleucyl anhydride (2) from L-isoleucine at the first time. Compound (2) was led to a pyrazine-carboxaldehyde (13), which was treated with p-methoxymethoxyphenylmagnesium bromide to afford an alcohol (14) in a quantative yield. The alcohol (14) was oxidized to ketone (16), which was subjected to the Pummerer reacton and the following hydrolysis to give (+)-septorine.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.937-947
Published online:
DOI: 10.3987/COM-91-5688
Reactions of Cyclohexyl and Aryl Pyrazinyl Sulfoxides with Trifluoroacetic Anhydride

Makoto Shimazaki, Miyuki Hikita, Tomoko Hosoda, and Akihiro Ohta*

*Tokyo College of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan

Abstract

Cyclohexy pyrazinyl sulfoxides reacted with trifluoroacetic anhydride to give 1-cyclohexenyl pyrazinyl sulfides and/or cyclohexyl hydroxypyrazinyl sulfides. The presence of alkyl groups on the pyrazine ring is essential to obtain the latter compounds.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.949-963
Published online:
DOI: 10.3987/COM-91-5698
Cobalt-mediated Alkylation of Siloxy Furans

John G. Stuart and Kenneth M. Nicholas*

*Department of Chemistry and Biochemistry, University of Oklahoma, Nrman, Oklahoma 73019, U.S.A.

Abstract

Dicobalt hexacarbonyl complexes of propargylium and α-vinylpropargylium cations couple efficiently with 2-trimethylsilyloxyfuran (5), 4-trimethylsilyloxy-2-benzyloxymethylfuran (15) and 2-trimethylsilyl-3-trimethylsilyloxy-4-ethylbenzo[b]furan (20) to produce the corresponding complexed furan derivatives in good yields. A convenient procedure for introducing the 2,4-enyne moiety regio- and stereoselectively into the above heterocycles using this methodology is described.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.965-973
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DOI: 10.3987/COM-91-5700
Stereoselective Syntheses of Spicy Components in Peppers

Akihiro Ohta,* Yoshiko Tonomura, Junko Sawaki, Naohito Sato, Hitomi Akiike, Mizue Ikuta, and Makoto Shimazaki

*Tokyo College of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan

Abstract

The Syntheses of (E)-α,β-unsaturated amides were accomplished from chloroacetamides and alkyl halides via β-elimination of the pyrazinylsulfinyl group, and some of the products are spicy components of piperaceous plants.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.975-984
Published online:
DOI: 10.3987/COM-91-5702
Electron Impact Mass Spectra of Some 2’-,3’- and 4’-Substituted Thiophene-2- and 3-Carboxanilides

Cristina Lea Barbieri,* Leopoldo Ceraulo, Paolo De Maria, Antonella Fontana, Domenico Spinelli, and Luca Zuppiroli

*Dipartimento di Chimica Organica "A Mangini", Università degli Studi di Bologna, Via S.Donato 15, 40127 Bologna, Italy

Abstract

The electron impact mass spectra (EI/MS) of 2- and 3-carboxanilides are dominated by the peak due to the corresponding thenoyl cations formed by cleavage of the C-N amide bond. This reaction is not affected by the polar effect of the substituents present in the phenyl ring. Most of the 2’-substituted derivatives undergo a cyclisation reaction with ejection of the substituent. In addition, for 2’-methyl and 2’-ethyl derivatives of both series of thiophene anilides a cryptic "ortho"-effect was suggested as responsible of the charge retention in the aniline moiety.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.985-990
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DOI: 10.3987/COM-91-5708
Structure and Stereochemistry of Divaricine, a New Bisindole Alkaloid from Strychnos divaricans Ducke.

Rabindranath Mukherjee,* Bagnolia A. da Silva, Bhupesh C. Das, Paul A. Keifer, and James N. Shoolery

*Institut de Chimie des Substances Naturelles, C.N.R.S., 1 avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France

Abstract

The complete stereostructure of divaricine, a new bisindole alkaloid from Srychnos divaricans Ducke., has been determined mainly by the use of one - and two-dimensional nmr techniques.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.991-1002
Published online:
DOI: 10.3987/COM-91-5719
Preparation of a Series of Oligo[thiophene-2,5-diyl]vinylenes

Juzo Nakayama* and Toru Fujimori

*Department of Chemistry, Faculty of Science, Saitama University, Saitama, Saitama 338-8570, Japan

Abstract

Preparation of a series of oligo[thiophene-2,5-diyl]vinylenes (3) is reported. Compounds containing an even number of thiopehene rings were synthesized by the carbonyl coupling of thiophenecarbaldehydes with a low-valent titanium reagent and those carrying an odd number of thiophene rings by the coupling of thiophenecarbaldehydes with Wittig-Horner (Wittig) reagents. Uv-vis spectral feature of these compounds is also reported.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.1003-1012
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DOI: 10.3987/COM-91-5720
Fused Imidazophenothiazines: Studies on the Bernthsen Thionation of 1-Methyl-6-(p-tolylamino)benzimidazole and 2-Methyl-1-phenylbenezimidazole

Pilar López-Alvarado, Carmen Avendaño,* and J. Carlos Menéndez

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

Abstract

Thionation of 1-methyl-6-(p-tolylamino)benzimidazole (obtained from 1-methyl-6-aminobenzomidazole and p-tolyllead triacetate) afforded a 7:3 mixture of two isomeric imidazophenothiazines, by inclusion of sulphur into the C7 and C2 ’ or C5 and C2’ positions, respectively. The capability of 1-arylbenzimidazoles to cyclize to a fused imidazophenothiazine was also shown. These results are discussed in comparison to those previously obtained on 2-methyl-1-phenyl-5-phenylaminobenzimidazole, a more complex system where both diarylamine units are present.

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Paper | Regular issue | Vol 32, No. 5, 1991, pp.1013-1016
Published online:
DOI: 10.3987/COM-91-5722
Effective Synthesis of 7-Benzylidenefuro[3,4-b]pyridin-5-one

Nagatoshi Nishiwaki, Mitsuo Komatsu, and Yoshiki Ohshiro*

*Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565, Japan

Abstract

The title compound (5) was synthesized by silica gel assisted cyclization of 2-phenylethynylpyridine-3-carboxylic acid (3). Its was also synthesized from 3-cyano-2-phenylethynylpyridine (6) in good yield by basic cyclization and dehydration processes.

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21 data found. 1 - 21 listed