Special Issue

Koji Nakanishi's Special Issues, Vol. 47, No. 2, 1998

50 data found. 31 - 50 listedFirst Previous
Paper | Special issue | Vol 47, No. 2, 1998, pp. 911 - 919
Published online:
DOI: 10.3987/COM-97-S(N)100
Lead Tetraacetate Oxidation of (±)-N-Acylnoraporphines: Facile Synthesis of 4α-Hydroxynoraporphines and 4α-Hydroxyaporphines

Hiromichi Ogasawara, Masaji Suzuki, Tomohiro Shiohara, and Osamu Hoshino*

*Faculty of Pharmaceutical Sciences, Science University of Tokyo, 12, Ichigaya Funagawara-machi, Shinjuku-ku, Tokyo 162-0826, Japan


Lead tetraacetate oxidation of N-trifluoroacetylwilsonirine (4a) and -nordomesticine (4b) in acetic acid at room temperature gave exclusively 4α-acetoxy-N-trifluoroacetylwilsonirine (7a) and -nordomesticine (7b), which were also obtained in good yield by oxidation in dichloromethane at 0°C and successive treatment with acetic acid. N-Ethoxy-carbonylwilsonirine (6a) was converted into 4α-hydroxyglaucine (epicataline)(15a) by the present methodology.

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Paper | Special issue | Vol 47, No. 2, 1998, pp. 921 - 931
Published online:
DOI: 10.3987/COM-97-S(N)101
Studies on Synthesis of Araplysillins via Oxidative Cyclisation of o-Phenolic Oxime-Acid Derivatives Using Phenyliodonium Diacetate

Masatoshi Murakata, Kohei Yamada, and Osamu Hoshino*

*Faculty of Pharmaceutical Sciences, Science University of Tokyo,12, Ichigaya Funagawara-machi, Shinjuku-ku, Tokyo 162-0826, Japan


Efficient synthetic approaches of cyclohexadienonespiroisoxazoline-amides (1), which could be useful as intermediates for the synthesis of dibromotyrosine derived marine natural products araplysillins, are described. Direct cyclisation of o-phenolic oxime-amide (5) with phenyliodonium diacetate (PIDA) produced 1. Amidation of cyclohexadienonespiroisoxazoline-acid (6) also took place efficiently to afford 1.

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Paper | Special issue | Vol 47, No. 2, 1998, pp. 933 - 950
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DOI: 10.3987/COM-97-S(N)103
[2+2] Versus [4+2] Cycloaddition Reactions of 1,3-Diaza-1,3-butadienes with Various Mono- and Disubstituted Ketenes and Supporting Mechanistic Considerations

Sucharita Mukherjee, Sujit N. Mazumdar, Arun K. Sharma, and Mohinder P. Mahajan*

*Department of Chemistry, North-Eastern Hill University, Shillong-793003, Meghalaya, India


Reactions of 1,3-diaza-1,3-butadienes with various mono- and disubstituted ketenes alongwith the associated interesting mechanistic features involved are reported. Reactions of 1,3-diazabutadienes with monosubstituted ketenes e.g. cyano-, p-nitrophenyl-, succinimido-, phthalimido- and phenoxyketenes gave [4+2] cycloadducts irrespective of the nature of azadiene and/or ketene substituents. However, diphenylketene underwent [2+2] cycloaddition reactions with 1,3-diazabutadienes (1a) and gave [4+2] adducts with 1b, having electron donating function at 2-position. Interestingly, the reactions of 4-(N-arylamino)-1,3-diaza-1,3-butadienes (19) with diphenylketene gave simple nucleophilic addition products (22), whereas, their reaction with dimethylketene, yielded [4+2] cycloadducts (23). The factors influencing [2+2] versus [4+2] and cyclic versus acyclic products are also discussed.

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Paper | Special issue | Vol 47, No. 2, 1998, pp. 951 - 964
Published online:
DOI: 10.3987/COM-97-S(N)107
Enantioselective Creation of Quaternary Carbon Centers through Addition- Elimination Reaction: Asymmetric Nitroolefination of 3-Substituted 2-Oxindoles

Kaoru Fuji,* Takeo Kawabata, Toshiumi Ohmori, Muhong Shang, and Manabu Node

*Institute for Chemistry, Kyoto University, Uji, Kyoto 611-0011, Japan


Nitroolefination of 3-substituted 2-oxindoles with nitroenamine (5) afforded the corresponding products having quaternary carbon centers with high ee in good yield. Application of this method to concise syntheses of (-)-esermethole (24) and (-)-pseudophrynaminol (28) is described.

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Paper | Special issue | Vol 47, No. 2, 1998, pp. 965 - 975
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DOI: 10.3987/COM-97-S(N)108
MCR 6: Chiral 2,6-Piperazinediones via Ugi Reactions with α-Amino Acids, Carbonyl Compounds, Isocyanides and Alcohols

Ivar Ugi,* Werner Hörl, Cordelia Hanusch-Kompa, Thomas Schmid, and Eberhardt Herdtweck

*Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, Lichtenbergstrasse 4, D-85747 Garching, Germany


A simple one-pot reaction based on the well known Ugi reaction for the generation of 2,6-piperazindiones is described, involving the multicomponent reaction of α-amino acids, carbonylcompounds, isocyanides and alcohols.

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Note | Special issue | Vol 47, No. 2, 1998, pp. 977 - 984
Published online:
DOI: 10.3987/COM-97-S(N)23
Ring Opening SN2’ Reactions of 1,4,5,8-Diepoxy-1,4,5,8-tetrahydroanthracenes by Organolithium Reagents

Odón Arjona,* Marisa León, and Joaquín Plumet*

*Departamento de Química OrgÁnica I., Facultad de Química., Universidad Complutense de Madridas, Ciudad Universitaria, E-28040 Madrid, Spain


The nucleophilic SN2’ bridge opening of diepoxytetrahydroanthracenes with organolithium reagents to produce hydroanthracene derivatives shows a dependence of the excess of reagent as well as the relative stereochemistry of the oxygen bridge.

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Note | Special issue | Vol 47, No. 2, 1998, pp. 985 - 990
Published online:
DOI: 10.3987/COM-97-S(N)62
Dioncophyllinol D, the First 4-Hydroxylated Naphthylisoquinoline Alkaloid, from the Leaves of Triphyophyllum peltatum

Gerhard Bringmann,* Matthias Wenzel, Markus Rückert, Kristina Wolf, Stefan Busemann, Manuela Schäffer, and Laurent Aké Assi

*Institut fr Organische Chemie, Universitat Wurzburg, Am Hubland D-97074 Wurzburg, Germany


The first isolation of a 4-hydroxylated naphthylisoquinoline alkaloid, dioncophyllinol D (5), from the leaves of Triphyophyllum peltatum (Dioncophyllaceae), is described. Its structural elucidation is based mainly on NMR, degradative, and computational methods. With its rare 7,8’-linkage between the isoquinoline and naphthalene parts, 5 is one of the very few naphthylisoquinolines without a stable configuration at the biaryl axis.

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Note | Special issue | Vol 47, No. 2, 1998, pp. 991 - 1004
Published online:
DOI: 10.3987/COM-97-S(N)64
Some Applications of the Regioselective Lithiation of α-Carbolines

Cyril Papamicaël, Georges Dupas,* Guy Quéguiner, and Jean Bourguignon

*Laboratoire de Chimie Organique Fine et Heterocyclique de l'IRCOF, UPRESA 6014 CNRS, INSA de Rouen, BP08, 76131, Mont-Saint-Aignan Cedex, France


Regioselective metallation of the 3-carboxamido-α-carboline (1) afforded various 4-substituted-3-carboxamido-α-carbolines. Subsequent cross-coupling methodology applied to the 4-iodo-3-carboxamido-α-carboline (2e) led to 4-aryl-3-carboxamido-α-carbolines. Regioselective lithiation of 3-pivalamido-α-carboline led to 3,4-diaminopyrido[2,3-b]indole (7). Condensation of this diamine with (dichloromethylene)dimethylammonium chloride was then studied and an unusual reaction was observed. Some derivatives of imidazopyrido[2,3-b]indole were thus obtained.

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Note | Special issue | Vol 47, No. 2, 1998, pp. 1005 - 1012
Published online:
DOI: 10.3987/COM-97-S(N)69
New Steroidal Lactones from Withania coagulance

Atta-ur-Rahman,* Muhammad Shabbir, Dur-e-Shahwar, M. Iqbal Choudhary,* Wolfgang Voelter, and Dirk Hohnholz

*International Centre for Chemical Sciences, H. E. J. Research Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan


Four new withanolides, coagulin B (1), coagulin C (2), coagulin D (3) and coagulin E (4) were isolated from the aerial parts of Withania coagulance. The structures (1-4) have been determined through spectroscopic studies.

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Note | Special issue | Vol 47, No. 2, 1998, pp. 1013 - 1015
Published online:
DOI: 10.3987/COM-97-S(N)75
Oxime Ethers as Structure Analogs of Clavulanic Acid

Hans Rudolf Pfaendler* and Helmut Meffert

*Institut für Organische Chemie, Universität München, Karlstrasse 23, D-80333 München, Germany


The reaction of racemic p-nitrobenzyl 1-aza-3,7-dioxobicyclo[3.2.0]beptane-2-carboxylate with methoxyamine leads to an oxime ether. The corresponding potassium salt is stable in neutral aqueous solution. However, it neither shows any significant activity as an antibacterial nor as a β-lactamase inhibitor.

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Note | Special issue | Vol 47, No. 2, 1998, pp. 1017 - 1022
Published online:
DOI: 10.3987/COM-97-S(N)79
Alkyl 2-[2,2-Disubstituted Ethenyl]amino-3-dimethylaminopropenoates in the Synthesis of Heterocyclic System. An Alternative Method for Preparation of 3-Amino-4H-pyrido[1,2-a]pyrimidin-4-ones

Lovro Selic, Sonja Strah, Renata Toplak, and Branko Stanovnik*

*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, P.O. Box 537, SLO-1000 Ljubljana, Slovenia


Substituted 3-amino-4H-pyrido[1,2-a]pyrimidin-4-ones (6) were prepared by treatment of 2-aminopyridines (1) with alkyl 2-[2,2-disubstituted ethenyl]amino-3-dimethylaminopropenoates (2) in which 3-[2,2-disubstituted ethenyl]amino-4H-pyrido[1,2-a]pyrimidin-4-ones (3 - 5) were formed. The removal of the N-protecting group with hydrazine afforded compounds (6).

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Note | Special issue | Vol 47, No. 2, 1998, pp. 1023 - 1027
Published online:
DOI: 10.3987/COM-97-S(N)91
Louludinium Chloride, an Azabicyclononane Alkaloid from the Marine Cyanophyte Lyngbya gracilis

Wesley Y. Yoshida and Paul J. Scheuer*

*Department of Chemistry, University of Hawaii at Manoa, 2545 Tha Mall, Honolulu, Hawaii 96822-2275, U.S.A.


A blue-green alga, Lyngbya gracilis, which was collected in the lagoon of Palmyra island, yielded a single metabolite, louludinium chloride (4). It is a rarely encountered azabicyclo[3.3.0]nonane derivative with moderate activity in the KB assay.

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Note | Special issue | Vol 47, No. 2, 1998, pp. 1029 - 1032
Published online:
DOI: 10.3987/COM-97-S(N)92
A New and Efficient Synthesis of the μ Opioid Receptor Antagonists 14-O-Methyl-and 14-O-Ethylnaloxone and -naltrexone

Roland Krassnig, Martin Koch, Herwig K. Jennewein, Elisabeth Greiner, and Helmut Schmidhammer*

*Institute of Pharmaceutical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria


The μ opioid receptor antagonists 14-O-methyl- and 14-O-ethylnaloxone (3 and 4, respectively) and 14-O-methyl- and 14-O-ethylnaltrexone (5 and 6, respectively) have been prepared in a three-step sequence starting from either naloxone (1) or naltrexone (2). The 3-hydroxy group of 1 and 2 was protected with a benzyl group prior to 14-O-alkylation with either dimethyl or diethyl sulfate to give the enol ethers (9 - 12). Acid hydrolysis afforded compounds (3 - 6).

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Note | Special issue | Vol 47, No. 2, 1998, pp. 1033 - 1042
Published online:
DOI: 10.3987/COM-97-S(N)94
Iron Chelators of the Class of Pyridoxal Acylhydrazone. Part 5. Crystal Structure and Patterns of Hydrogen Bonding in Pyridoxal Isonicotinoyl Hydrazone (PIH)

Shalom Sarel,* Shmuel Cohen, and Shelly Avramovici-Grisaru

*Department of Pharmaceutical Chemistry, Hebrew University School of Pharmacy, P. O. Box 12065, Jerusalem 91120, Israel


The water-free Pyridoxal Isonicotinoyl Hydrazone {PIH} C14H14N4O3 (mp 268°C) was synthesized, and its crystal structure determined from three-dimensional X-Ray data. The chelator crystallizes in the space group P21/n with Z = 4 and cell dimensions : a =13.072(6) Å, b =13.06(5) Å, c = 8.186(2) Å, b =90.2I°(2). The data produced here confirms that PIH crystallizes in the non-dipolar form, assembled as, 3-D tetramer, composed of a planar 16-membered ring dimer, involving intermolecular H-bondings between the acoholic hydroxyl-oxygen(O2) and the azinic (N3-H) hydrogen. The dimeric macrocycle is attached to two PIH molecules in a perpendicular fashion, and in opposite orientations, to form a 3-D tetramer, by involving intermolecular H-contacts between the alcoholic hydroxyl-H and the pyridinic ring-nitrogen (N4). The azinic-nitrogen (N2) is intramolecularly H-bonded with the phenolic H {O1-H }, to form a stable six-membered ring system.

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Note | Special issue | Vol 47, No. 2, 1998, pp. 1043 - 1049
Published online:
DOI: 10.3987/COM-97-S(N)109
On the Reactivity of Hydroximoyl Chlorides.Preparation of 2-Arylimidazolines

Héctor Salgado-Zamora,* Elena Campos, Rogelio Jiménez, and Humberto Cervantes

*Departamento de Químíca OrgÁnica, Escuela Nacional de Ciencias Biológicas, I. P. N., Prol. Carpio y Plan de Ayala S/N,11340, Mexico, D.F.


Elimination of the hydroxylamino portion in arylhydroximoyl chlorides upon nucleophilic addition of ethylenediamine rendered an alternative procedure for 2-arylimidazolines preparation.

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Review | Special issue | Vol 47, No. 2, 1998, pp. 1051 - 1066
Published online:
DOI: 10.3987/REV-97-SR(N)5
How Nature Synthesizes B12 without Oxygen. Discoveries along the Ancient, Anaerobic Pathway

A. I. Scott

*Department of Chemistry, Texas A & M University, College Station, Texas 77843-3255, U.S.A


A second pathway to vitamin B12 has been discovered in anaerobic and microaerophilic organisms such as Propionibacterim shermanii. Although running parallel to the biosynthetic route established in the aerobe, Pseudomonas denitrificans, the anoxic pathway which has existed for ca. 4x109 years exhibits many differences from the aerobic sequence, including early insertion of cobalt, a ring contraction mechanism which does not use oxygen, and the extrusion of acetaldehyde (rather than acetic acid) as the two carbon fragment. The main features of both biosynthetic routes to B12 are compared and contrasted.

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Review | Special issue | Vol 47, No. 2, 1998, pp. 1067 - 1110
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DOI: 10.3987/REV-97-SR(N)6
Biologically Active Substances of Japanese Inedible Mushrooms

Toshihiro Hashimoto and Yoshinori Asakawa*

*Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamabouji, Yamashiro-machi, Tokushima, 770-8514, Japan


As a part of our systematic investigation of biologically active substances of inedible mushrooms, we studied the chemical constituents of three Basidiomycetes fungi (Cryptoporus volvatus, Lentinellus ursinus and Paxillus atrotomentosus), five inedible Ascomycetes fungi (Daldinia concentrica, Daldinia vernicosa, Entonaema splendens, Hypoxylon truncatum and Ascoclavulina sakaii), and isolated a number of novel terpenoids, phenolics and nitrogen-containing compounds. The isolation, structural determination and biological activity of the new compounds will be discussed.

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Review | Special issue | Vol 47, No. 2, 1998, pp. 1111 - 1133
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DOI: 10.3987/REV-97-SR(N)7
Bioactive Taxoids from Japanese Yew Taxus cuspidata and Taxol Biosynthesis

Jun'ichi Kobayashi* and Hideyuki Shigemori

*Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan


A series of new taxoids, named taxuspines A ~ H and J ~ Z (1 - 25), have been isolated together with 37 known taxoids (26 ~ 62) including taxol (42) from the Japanese yew Taxus cuspidata Sieb. et Zucc. These new taxoids possessed various skeletons containing 5/7/6, 6/10/6, 6/5/5/6, 6/8/6, or 6/12-membered ring systems. Among the new taxoids, some non-taxol-type compounds remarkably reduced CaCl2-induced depolymerization of microtubules, or increased cellular accumulation of vincristine in multidrug-resistant tumor cells as potent as verapamil. Here we describe our recent results on the isolation, structure elucidation, and bioactivity of these new and known taxoids as well as recent development of taxol biosynthesis.

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Review | Special issue | Vol 47, No. 2, 1998, pp. 1135 - 1177
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DOI: 10.3987/REV-97-SR(N)8
The Synthesis and Reactions of Heterocycles under High Pressures: Part II

Kiyoshi Matsumoto,* Makoto Kaneko, Hideki Katsura, Naoto Hayashi, Takane Uchida, and R. Morrin Acheson

*Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-Nihonmatsu-cho, Sakyo-ku, Kyoto 606-01, Japan


Recent advances in synthesis and reactions of heterocycles under high pressures are described.

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Review | Special issue | Vol 47, No. 2, 1998, pp. 1179 - 1205
Published online:
DOI: 10.3987/REV-97-SR(N)9
Isoprenoid-substituted Flavonoids from Artocarpus Plants (Moraceae)

Taro Nomura,* Yoshio Hano, and Miwa Aida

*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan


Many phenolic compounds including flavonoids have been isolated from the plants of Morus and Artocarpus species (Moraceae). Most of Morus and Artocarpus flavonoids are characterized by the structure bearing an isoprenoid side chain at the C-3 position of flavone skeleton and 2’,4’-dioxygenated (e.g. morusin, 4) or 2’,4’,5’-trioxygenated (e.g. artonin E, 51) pattern in the B ring. Particularly, some of Artocarpus flavonoids have a unique structure having the C-C linkage between an isoprenoid side chain at the C-3 position and the 6’-carbon of the B ring. These flavones considered to be biogenetically derived from the C-3 isoprenoid-substituted flavones. Some of the Artocarpus flavonoids, such as artonin I (31), have been regarded as optically active Diels-Alder type adducts. The structure of artonin I (31) was established utilizing the enzyme system of Morus alba cell cultures which specifically produced the natural Diels-Alder type adducts. Some of the isoprenylated flavonoids from the moraceous plants showed the interesting biological activity. Artonin E (51) was a potent inhibitor of arachidonate 5-lipoxygenase and inhibited the release of the TNF-α from BALB/3T3 cells by treatment of okadaic acid, stronger than morusin (4) did. This article reviews the chemistry and biological activities of isoprenoid-substituted flavonoids isolated from the root barks and/or barks of Artocarpus species.

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