Regular Issue

Vol. 26, No. 10, 1987

22 data found. 1 - 22 listed
Communication | Regular issue | Vol 26, No. 10, 1987, pp.2573-2578
Published online:
DOI: 10.3987/R-1987-10-2573
Phaeanthine-2’a-N-oxide and Pycmanilline, New Bisbenzylisoquinoline Alkaloids from Pycnarrhena manillensis

Jacinto C. Regalado, Jr., Cong-yuan Gao, Emil Fu, Fu-tyan Lin, Mei-chao Lin, Lan K. Wong, and Paul L. Schiff, Jr.

*Department of Pharmacognosy, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, U.S.A.

Abstract

Chromatography of an ethanolic extract of pycrarrhena manillensis over silica gel afforded phaeanthine-2’α-N-axide (1) and pycmanilline (2) which were characterized as new bisbenzylisoquinoline alkaloids by a consideration of physicochemical data and the utilization of simple chemical reactions. Phaeathine-2’α-N-axide (1) was reduced to phaeanthine (3) while pycmanilline (2), a secobisbenzyliso-quinoline alkaloid, was prepared via oxidation of phaeanthine (3).

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Communication | Regular issue | Vol 26, No. 10, 1987, pp.2579-2581
Published online:
DOI: 10.3987/R-1987-10-2579
Asymmetric Synthesis via Heterocyclic Intermediates. Asymmetric Synthesis of (-)-(1S,2R)-Allocoronamic Acid

José L. Marco

*Instituto de Química Orgánica General, C. S. I. C., Calle Juan de Cierva, 3, 28006 Madrid, Spain

Abstract

The first total asynmetric synthesis of (-)-(1S, 2R)-allocoronamic acid is described.

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Communication | Regular issue | Vol 26, No. 10, 1987, pp.2583-2586
Published online:
DOI: 10.3987/R-1987-10-2583
Pyridine N-Oxides as Catalysts for Thione-thiol Rearrangement

Kazunobu Harano, Ikuo Shinohara, Motoji Murase, and Takuzo Hisano

*Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-hon-machi, Kumamoto 862-0973, Japan

Abstract

Pyridine N-oxides are efficient catalysts for rearrangement of 0,S-dialkyl dithiocarbonates to S,S-dialkyi dithiocarbonates. A Solid-Phase copolymer of 4-vinylpyridine N-oxide (P4VPNO) is also a useful catalyst. being nonvolatile and easily handled. The rearrangement products are served as useful precursors of thiols.

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Communication | Regular issue | Vol 26, No. 10, 1987, pp.2587-2590
Published online:
DOI: 10.3987/R-1987-10-2587
First Synthesis of 1-Trichloromethyl-6,7-dihydroxytetrahydroisoquinoline — An Imaginable Chloral-derived Mammalian Alkaloid

Gerhard Bringmann, Annette Hille, and Marianne Zsiska

*Organisch-Chemisches Institut, Universität Münster, Orleansring 23, D-4400 Münster, Germany

Abstract

1-Trichloromethyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (3c), a potential condensation product from dopamine (1) and chloral (2c), could be prepared for the first time, by a stepwise Bischler-Napieralski pathway, and, more directly, under special Pictet-Spengler conditions, The results indicate that 3c is not a probable alkaloid in man.

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Communication | Regular issue | Vol 26, No. 10, 1987, pp.2591-2598
Published online:
DOI: 10.3987/R-1987-10-2591
Approach to Natural Occurring α-Methylene Bis-γ-butyrolactones from (R)-1,2,-(O)-Isopropylideneglyceraldehyde as a Chiral Template

Toshio Suzuki, Shinko Kamada, Etsuko Sato, Yasuyuki Matsuda, Katsuo Unno, and Tetsuiji Kametani

*Department of Pharmaceutical Sciences, Akita University Hospital, Hondo, Akita 010, Japan

Abstract

Both 4-substituted tetrahydrofurano-γ-butyrolactones (12) and (16) which could be key intermedates leading to natural occurring α-methylene bis-γ-butyrolactones were synthesized by regio and stereoselective haloetherification of (8) and (9), followed by a reductive coupling reaction for the preparation of (12), whereas a stereoselective hydrogenation of the enol ether (15) derived from the bromide (14) for the preparation of (16), respectively.

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Communication | Regular issue | Vol 26, No. 10, 1987, pp.2599-2602
Published online:
DOI: 10.3987/R-1987-10-2599
Preparation of an α,β-Type of Ter- and Septithiophenes

Juzo Nakayama, Shigeru Murabayashi, and Masamatsu Hoshino

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

Abstract

An α,β-type of thiophene oligomers, 2,3’:4’,2”-terthiophene and 2,3’:4’,2”:5”,3’’’:4’’’,2””:5””,3””’:4””’,2”””-septithiophene, were synthesized through intramolecular reductive coupling reaction of diketo sulfides with a low-valent titanium reagent.

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Communication | Regular issue | Vol 26, No. 10, 1987, pp.2603-2606
Published online:
DOI: 10.3987/R-1987-10-2603
Synthesis of 1,2-Aziridino-2,3-dihydro-1H-pyrrolo[1,2-a]indole Derivatives Similar to the Activated Forms of Mitomycin

Shin-ichi Nakatsuka, Osamu Asano, and Toshio Goto

*Faculty of Agriculture, Gifu University, 1-1 Yanagito, Gifu, Gifu 501-1193, Japan

Abstract

Titled compounds, 8 and 12, were efficiently synthesized from 2,3-dihydro-1H-pyrrolo[1,2-a]indole derivatives by closure of the aziridine ring.

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Communication | Regular issue | Vol 26, No. 10, 1987, pp.2607-2609
Published online:
DOI: 10.3987/R-1987-10-2607
Facile Deoxygenation of Sulfoxides by Using Metal/Chiloromethylsilanes

Kazuo Nagasawa, Akemi Yoneta, Toshiyuki Umezawa, and Keiichi Ito

*Hokkaido College of Pharmacy, 7-1 Katsuraoka-cho, Otaru 047-02, Japan

Abstract

Deoxygenation of a various kind of sulfoxides including optically active one by Zinc/Dichlorodimethylsilane proceeds under very mild conditions to furnish the corresponding sulfides in high yields.

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Communication | Regular issue | Vol 26, No. 10, 1987, pp.2611-2614
Published online:
DOI: 10.3987/R-1987-10-2611
A Novel Synthetic Method of Lactams from1,3-Dioxin-4-ones via Intramorecular Ketene Trapping

Masayuki Sato, Hiromichi Ogasawara, Kazuhisa Takayama, and Chikara Kaneko

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan

Abstract

A novel route to four- and five-membered lactams from 1,3-dioxin-4-ones having an α-aminoalkyl side-chain at 5-or 6-position through cycloreversion to acylketenes followed by intramolecular ketene trapping by the amino function is described.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2615-2622
Published online:
DOI: 10.3987/R-1987-10-2615
Nitrogen Bridgehead Compounds. Part 67. Preparation of Novel Policyclic Quaternary Salts

István Bitter, Béle Pete, Béle Ágai, László Töke, Gábor Tóth, István Hermecz, Kálmán Simon, Zoltán Mészáros, and László Párkányi

*Department of Organic Chemical Technology, Technical University of Budapest, H-1521 Budapest, Gellért tér 4, Hungary

Abstract

The first representatives of new polycyclic ring systems - thiazolo- end oxazolo-[2,3-b] triazaphenalenes, benzoxazolo-and benzothiazolo-[2,3-b] triazaphenalenes and isoquinolo-[1,2-b]triazazaphenalenes - are prepared by the cycloaddition of pyrido[1,2-a]pyrimidine derivatives with cyclic azomethines.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2623-2637
Published online:
DOI: 10.3987/R-1987-10-2623
Studies on Aconitum Species V. Constituents of Aconitum yesoense var. macroyesoense (Nakai) Tamura

Hideo Bando, Koji Wada, Takashi Amiya, Kimiko Kobayashi, Yasuo Fujimoto, and Toshio Sakurai

*Hokkaido College of Pharmacy, 7-1 Katsuraoka-cho, Otaru 047-02, Japan

Abstract

Five new C20-diterpenoid alkaloids, 12-acetyldehydro-Iucidusculine, 12-acetyllucidusculine. 15-benzoylpseudokobusine,15-veratroylpseudokobusine, and yesoxine and 14 known alkaloids were isolated from A. yesoense var. macroyesoense (Nakai) Tamura. Structures of those compounds were determined on the basis of their spectral and chemical data. Structure of an unusual epoxide, yesoxine, was determined by X-ray analysis and was a first example having an epoxy group at C(16 and 17).

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2639-2656
Published online:
DOI: 10.3987/R-1987-10-2639
Thienospirans V: Thienospirans via Directed Lithiations

Fritz Sauter, Peter Stanetty, Hannes Fröhlich, and Wolfgang Ramer

*IInstitute of Organic Chemistry, Vienna University of Technology, Getreidemarkt 9, A-1060 Vienna, Austria

Abstract

Using halogen-metal exchange and orthodirected metalation methodologies spiro[thieno[b]-furans] 2 and 3 were synthesized starting from 3-bromothiophene, in one case proceeding via cyclization of the 2,3-difunctionalized thiophenes 6 and in the other case proceeding via cyclization of the isomeric compounds 8.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2657-2672
Published online:
DOI: 10.3987/R-1987-10-2657
Thienospirans VI: Spiro-substituted Thieno[3,2-c]furans by Regioselective Lithiations

Fritz Sauter, Peter Stanetty, and Hannes Fröhlich

*IInstitute of Organic Chemistry, Vienna University of Technology, Getreidemarkt 9, A-1060 Vienna, Austria

Abstract

The title substances 3 were obtained by cyclization of 3,4-disubstituted thiophenes 5 and 6, prepared in one-pot reactions starting from 3,4-dibromothiophene by means of two consecutive lithiations and additions of carbonyl compounds. By a combination of variation of the solvent and of the lithiating agent in the second metalation step and by influence of the substituent introduced in the first step it became possible to obtain good yields of either 3,4-disubstituted thiophenes ( 5 and 6) by metal-halogen exchange , 2,3-disubstituted 4-bromothiophenes (7) by directed lithiation, or 2,4-disubstituted 3-bromothiophenes (9) by a -I-effect controlled ortho-metalation.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2673-2676
Published online:
DOI: 10.3987/R-1987-10-2673
Synthesis and Structural Confirmation of 5,6-Cyclopenteno-5-deazapterin

Edward C. Taylor and John C. Warner

*Department of Chemistry, Princeton University , Princeton, New Jersey 08544, U.S.A.

Abstract

Condensation of 2,4-diamino-6(1H)-pyrimidinone with 1-formyl-1-cyclopentene in 60% acetic acid gives 5,6-cyclopenteno-5-deazapterin (2). The 2-pivaloyl derivative of 2 was then synthesized in an unequivocal manner by Diels-Alder cycloaddition of 2-pivaloylamino-7-methylthio-6-azapterin (3) with 1-(N-morpho1ino)cyclopentene to give 5,6-cyclopenteno-2-pivaloylamino-7-methylthio-5-deazapterin (4), followed by Raney nickel desulfurization.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2677-2681
Published online:
DOI: 10.3987/R-1987-10-2677
Flash Vacuum Pyrolysis of Pyridazine N-Oxides

Akio Ohsawa, Takashi Itoh, and Hiroshi Igeta

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

Abstract

Flash vacuum pyrolysis of 6-unsubstituted pyridazine 1-oxides afforded nitriles and pyrroles. 6-Phenylpyridazine 1-oxides gave 2-phenyloxazole together with nitriles and pyrroles. 6-Methylpyridazine 1-oxide and 3,6-dimethylpyridazine 1-oxide afforded naphthalene and benzene, respectively, together with other products. The formation mechanism of these products was speculated.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2683-2690
Published online:
DOI: 10.3987/R-1987-10-2683
Photoreaction of Phthalimides Possessing an ortho-Methylphenyl Group in Their N-Side Chain. Synthesis of Tetracyclic Nitrogen Heterocycles

Minoru Machida, Mayumi Nakamura, Kazuaki Oda, Haruko Takechi, Kosei Ohno, Hideo Nakai, Yasuhiko Sato, and Yuichi Kanaoka

*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan

Abstract

Upon irradiation phthalimides (5 and 8) possessing an 9-methylphenyl group in their N-side chain gave mainly the tetracycilc ring systems (9 and 10). it was shown that the photocyclization occurs at ε- or ζ-position across the carbons of the benzene ring (B ring).

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2691-2701
Published online:
DOI: 10.3987/R-1987-10-2691
Catalytic Hydrogenation of 2,5-Dialkylpyrazines and 3,6-Dialkyl-2-hydroxypyrazines

Akihiro Ohta, Yukari Okuwaki, Tsuyoshi Komaru, Mieko Hisatome, Yasushi Yoshida, Jun Aizawa, Yumi Nakano, Hiroko Shibata, Takuya Miyazaki, and Tokuhiro Watanabe

*Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan

Abstract

Hydrogenation of several 2,5-dialkylpyrazines and 3.6-dialkyl-2-hydroxypyrazines was achieved in the presence of platinum oxide. In the former cases, the corresponding trans piperazines were mainly obtained. In the latter cases, the products were further treated with lithium aluminum hydride to give mainly the cis isomers.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2703-2710
Published online:
DOI: 10.3987/R-1987-10-2703
An Efficient Synthesis of 14-Halogenomethyl-substituted C-Normorphinans

Martin Kratzel and Wilhelm Fleischhacker

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

Abstract

Nucleophilic ring-opening reaction of 7,14-cyclo-dihydrocodeinone 1 resulted in a watersoluble quaternary ammonium salt 3. However, similar reaction of 1 under acetalization conditions led to the ring cleavaged 14-halogenomethylacetals 4, 7 and 8 (a-c) in high yields. When the acetals were hydrolyzed, the formation of cyclic ammDnium compounds (3) was unavoidable.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2711-2716
Published online:
DOI: 10.3987/R-1987-10-2711
Palladium-catalyzed Cross-coupling of Phenylboronic Acid with Heterocyclic Aromatic Halides

Johannes Stavenuiter, Martin Hamzink, Rob van der Hulst, Gijsbert Zomer, Gerard Westra, and Erik Kriek

*National Institute of Public Health and Environmental Hygiene, P.O.Box 1, 3720 BA Bilthoven, The Netherlands

Abstract

The coupling reaction of bromo- and - iodopyridines 1 with phenylboronic acid (2a) by Pd(Ph3 P)4 provides a convenient route to phenylpyridines, even when electrondonating or - withdrawing substituents are present. The method is also successful for the preparation of other phenylated N-containing heterocycles 5 as phenylquinolines and -pyrimidines.

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Paper | Regular issue | Vol 26, No. 10, 1987, pp.2717-2725
Published online:
DOI: 10.3987/R-1987-10-2717
A Novel Synthesis of Benzofuran and Related Compounds. IV. The Vilsmeier Reaction of 3,5-Dimethoxyphenylthiomethyl Compounds

Takashi Hirota, Yosuke Tashima, Kenji Sasaki, Tetsuo Namba, and Shohei Hayakawa

*Faculty of Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan

Abstract

A novel synthesie of 2-substituted 4,6-dimethoxybenzothiophenes by the Vilsmeier reaction of 3,5-dimethoxyphenylthiomethyl derivatives is described.

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Review | Regular issue | Vol 26, No. 10, 1987, pp.2727-2755
Published online:
DOI: 10.3987/R-1987-10-2727
Synthesis of Vicinally Substituted Nitropyridine Derivatives and Their N-Oxides

Ryszard Gawinecki and Danuta Rasala

*Institute of Chemistry, Pedagogical University, 25-020 Kielce, Poland

Abstract

The synthetic methods leading to 4- and 2-substituted 3-nitropyridines and 3-substituted 4- end 2 nitropyridines are reviewed in this paper. Their preparative convenience is discueeed.

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Review | Regular issue | Vol 26, No. 10, 1987, pp.2757-2772
Published online:
DOI: 10.3987/R-1987-10-2757
The Chemistry of Antiaromatic Azacycl[3.3.3]azines

Yoshiro Matsuda and Hiromi Gotou

*Faculty of Environmental Studies, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki 852-8521, Japan

Abstract

The syntheses and reactions of antiaromatic azacycl[3.3.3]azines are reviewed.

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22 data found. 1 - 22 listed