HETEROCYCLES
An International Journal for Reviews and Communications in Heterocyclic ChemistryWeb Edition ISSN: 1881-0942
Published online by The Japan Institute of Heterocyclic Chemistry
Regular Issue
Vol. 48, No. 5, 1998
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■ Synthesis and Reactions of a Novel Furo[3,4-d]thiazole
Stephan Reck, Christian Näther, and Willy Friedrichsen*
*Institut für Organische Chemie, Universität Kiel, Olshausenstrasse. 40, D-24098 Kiel, Germany
Abstract
The synthesis of a novel furo[3,4-d]thiazole (6) and some cycloadditions are reported. Density functional theoretical calculations are in accord with the reactivity of this system.
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■ Synthesis and Properties of Porphyrin-linked Indolizine
Kiyoshi Matsumoto,* Akira Ogasawara, Shinya Kimura, Naoto Hayashi, and Takahisa Machiguchi
*Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-Nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan
Abstract
The synthesis of porphyrin-linked indolizine has been achieved for the first time in a simple process from the reaction between a 5-formylindolizine (8) and dipyrrolomethane (10) giving the desired 1,7-bisindolidinoporphyrin (12). The electronic effect of the heterocyclic nuclei (12) is prominently observed in the Soret band of the UV — VIS spectrum. Temperature-dependence 1H NMR analysis of 12 suggests the existence of an association of 12 causing restricted rotation around the bond between indolizine and porphyrin.
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■ Heteroaromatic Tripoles. Syntheses of Aminopyrimidine-Bispyridinium Salts and Bispyridiniopyrimidinaminides
Andreas Schmidt
*Ernst-Moritz-Arndt-Universität Greifswald, Institut für Chemie und Biochemie, Soldmannstrasse 16, D-17487 Greifswald, Germany
Abstract
Depending on the substitution pattern of the 4-aminophenyltrichloropyrimidine derivatives (1, 2) reaction with 4-dimethylaminopyridine and 4-(pyrrolidin-1-yl)pyridine, respectively, formed either the pyrimidine-dipyridinium salts (3, 4, 7, 8) or the tripolar species (5, 6, 9, 10) which are the first examples of mesomeric betainium salts.
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■ Corchorusosides A, B, C, D, and E, New Cardiotonic Oligoglycosides from the Seed of Corchorus olitorius L. (Moroheiya)
Masayuki Yoshikawa,* Toshiyuki Murakami, Hiromi Shimada, Nobuyuki Fukada, Hisashi Matsuda, Yutaka Sashida, and Johji Yamahara
*Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8412, Japan
Abstract
The methanolic extract of the seeds of Corchorus olitorius L. (Moroheiya) was found to show inhibitory effect agatinst Na+,K+-ATPase and positive inotropic activity in the guinea pig isolated atria. Through bioassay-guided separation from the methanolic extract, new cardenolide oligoglycosides called corchorusosides A, B, C, D, and E were isolated together with six known cardenolide oligoglycosides. The structures of new corchorusosides were determined on the basis of chemical and physicochemical evidence. All cardenolide oligoglycosides from the seeds showed potent inhibitory activity against Na+,K+-ATPase, which was equivalent to those of digitoxin and ouabain. The methanolic extract, glycoside fraction, and principal glycoside showed potent acute toxicity by intraperitoneal administration, whereas they showed little acute toxicity by oral administration. Furthermore, by means of HPLC quantitative analysis of the cardiotonic oligoglycosides, it was found that the glycosides mainly distributed in the seeds, while the edible parts such as fresh young leaves and stems contained only trace amount.
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■ Rhodium(II)-catalyzed Cycloaddition of Cyclic Diazodicarbonyl Compounds with Nitriles. Synthesis of Tetrahydrobenzoxazoles, Tetrahydrobenzofurans, and Tetrahydrobenzodioxoles
Yong Rok Lee* and Jung Yup Suk
*Department of Industrial Chemistry, College of Engineering, Yeungnam University, Kyongsan 712-749, Korea
Abstract
A reaction of cyclic 2-diazodicarbonyl compounds with nitriles is described which affords tetrahydrobenzoxazoles, and tatrahydrobenzofurans and tetrahydrobenzodioxoles, depending on the structure of the nitriles.
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■ A New Indole Alkaloid from Sarcocephalus latifolius
Pedro Abreu* and António Pereira
*Chemistry Department, Faculty of Chemical Technology, New University of Lisbon, Quinta da Torre, 2825 Monte da Caparica, Portugal
Abstract
A new indole alkaloid, 19-O-ethylangustoline, as well as the known alkaloids angustoline, angustine, angustidine and nauclefine were isolated from the stem bark of Sarcocephalus latifolius (Smith) Bruce and characterised by spectral methods. The absolute stereochemistry at C-19 of angustoline and 19-O-ethylangustoline was determined by Horeau’s method and optical rotatory dispersion.
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■ Regioselective Synthesis and Spectral Characterization of Ethyl (Z)- and (E)-2-Alkylidene-4-oxothiazolidine-5-acetate Derivatives. Solvent Effects on the Z-E Isomerization
Rade Markovic* and Marija Baranac
*Faculty of Chemistry, University of Belgrade, Studentski trg 16, P.O.Box 158, 11001 Belgrade, Yugoslavia
Abstract
The title compounds containing an exocyclic double bond of exclusively the Z-configuration were prepared in anhydrous ethanol by the regioselective base catalyzed reaction of diethyl 2-mercaptobutanedioate with nitrile precursors possessing an acidic α-hydrogen. The 1H NMR data indicating the presence of both geometrical isomers in primarily nonpolar media favoring the E-form are presented in terms of the solvent influence on intra- and intermolecular H-bonding and stereochemical outcome of the reaction.
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■ Cycloadditions of Mesitonitrile Oxide with Hydroxy- and Methoxy-substituted Stilbenes. A Directing Hydrogen Bonding Model
Antonino Corsaro,* Giuseppe Buemi, Ugo Chiacchio, Venerando Pistarà, and Antonio Rescifina
*Dipartimento di Scienze Chimiche, Università di Catania, Viale A. Doria 6, I-95125 Catania, Italy
Abstract
The regioselectivity of the reaction of mesitonitrile oxide with o-hydroxystilbene in favour of the 5-(2-hydroxyphenyl) isomer (regioisomeric ratio 5:1) is accounted by a directing hydrogen bonding model, while for reactions of the p-hydroxy- and p-methoxystilbene which show a 2:1 ratio between the 5- and 4-regioisomer, an electron-donor effect is invoked. These phenomena of regioselectivity are supported by semiempirical AM1 calculations.
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■ Regioselective Synthesis of Several Heterocyclic Fused Azepines Using Diisobutylaluminum Hydride
Hidetsura Cho,* Kengo Murakami, Hiroyuki Nakanishi, Hirotaka Isoshima, Kazuhide Hayakawa, and Itsuo Uchida
*Central Pharmaceutical Research Institute, Japan Tobacco Inc., 1-1, Murasaki-cho, TAkatsuki-shi, Osaka, 569-1125, Japan
Abstract
5,6,7,8-Tetrahydrothieno[3,2-b]azepine, 5,6,7,8-tetrahydro-1H-furo[3,2-b]azepine, and 1,4,5,6,7,8-hexahydropyrrolo[3,2-b]azepine were synthesized by the ring expansion reaction of heterocyclic fused cyclohexanone oximes with diisobutylaluminum hydride (DIBAH). The mechanism of the reaction was different from that of Beckmann Rearrangement.
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■ 1-Arylamino-1H-imidazoles by "Oxidative Reduction" --- Conversion of 1-Arylamino-2,3-dihydro-1H-imidazole-2-thiones
Joachim G. Schantl* and Irene M. Lagoja
*Institut für Organische Chemie, Universität Innsbruck, Innrain 52, A-6020 Innsbruck, Austria
Abstract
Desulfurization of the thione function of N-arylthiosemicarbazides incorporated in a heterocyclic ring was achieved with 30% hydrogen peroxide in acetic acid. This reagent proved superior for the title transformation of thiones (1) into 2-unsubstituted 1H-imidazoles (5). In addition, structurally related substrates were also subjected to this procedure.
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■ Synthesis of Bis(N-methylpyrrole Oligopeptide-linked Hydroxamic Acids) and Effective DNA Cleavage by Their Vanadyl Complexes
Shigeki Hashimoto, Kazuo Yamamoto, Takao Yamada, and Yushin Nakamura*
*Department of Biological Science and Technology, Science University of Tokyo, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
Abstract
Dimeric N-methylpyrrole oligopeptide hydroxamic acids, which are connected at the carboxy termini via an alkylamino tether, have been newly synthesized. The plasmid DNA relaxation assay indicated that vanadyl-mediated DNA cleavage by these molecules is more effective than that by the corresponding monomeric ones. The cleavage activity of the dimeric complexes exhibited a maximum ratio for vanadyl / dimeric compounds of 2 whereas that of the monomeric ones exhibited a ratio of 1. Two vanadyl-hydroxamate complexing moieties are suggested to independently participate in the effective DNA cleavage by the dimeric complexes.
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■ Establishment of Efficient Hydroxylation at Angular Position of 4a-Aryl-trans-decahydroisoquinolines
Koji Kawai, Kuniaki Kawamura, and Hiroshi Nagase*
*Basic Research Laboratories, Toray Industries, Inc., 111, Tebiro, Kamakura, Kanagawa, 248, Japan
Abstract
Efficient hydroxylation method at angular 8a position of 4a-aryl-trans-decahydroisoquinolines was described. By utilizing the transformation process, syntheses of 2-methyl- and 2-cyclopropylmethyl-8a-hydroxy-4a-(3-methoxyphenyl)-6-oxo-trans-decahydroisoquinolines (13 and 17), the useful molecules as an opioid message substructure, were attained. The key step in this transformation was N-protection of enamine intermediate by 2,2,2-trichloroethoxycarbonyl chloride and subsequent epoxidation and hydride reduction.
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■ An Approach to Pyrimidine N-Oxides: Carboxamide Oximes as Precursors
Biserka Mlakar, Bogdan Stefane, Marijan Kočevar, and Slovenko Polanc*
*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, P.O. Box 537, SLO-1000 Ljubljana, Slovenia
Abstract
A method for the synthesis of pyrimidines N-oxides is described. Various carboxamide oximes were treated with the appropriate 1,3-dicarbonyl compounds or their equivalents in the presence of trifluoroacetic acid as a catalyst to give the corresponding pyrimidine N-oxides.
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■ Addition-Cyclization of 2-Hydroxy-2,3-dihydroindol-3-ones with Acetylenecarboxylates: Preparation of Furo[2,3-b]indoles
Tomomi Kawasaki, Chen-Ying Tang, Eiichi Koizumi, Hiroyuki Nakanishi, and Masanori Sakamoto*
*Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan
Abstract
The reaction of 2-hydroxyindol-3-ones (1) with dimethyl acetylenedicarboxylate (2a, DMAD) in the presence of base (triethylamine or sodium carbonate) underwent Michael addition followed by cyclization to produce 3a-hydroxyfuro[2,3-b]indoles (3).
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■ A New Regioselective Synthesis of Isopavine and Pavine Alkaloids via Double Cyclization of N-(1,2-Diarylethyl)-N-(2-phenylsulfinylethyl)formamide
Tatsumi Shinohara, Akira Takeda, Jun Toda, and Takehiro Sano*
*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan
Abstract
Pummerer reaction of N-[1,2-(3,4-dimethoxyphenyl)ethyl]-N-(2-phenylsulfinylethyl)formamide (9) using trifluoroacetic anhydride and boron trifluoride etherate caused double cyclization to give N-formylisopavine (21). Acid catalyzed cyclization of the 1,2-dihydroisoquinoline (23) prepared from 4-phenylthio-1,2,3,4-tetrahydroisoquinoline (11) gave N-formylpavine (26). LiAlH4 reduction of the N-formates (21 and 26) gave (±)-O-methylthalisopavine (4) and (±)-argemonine (5), respectively.
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■ A Mild and Efficient Dehydrogenation Method for 3-Carboxy-1,2,3,4-tetrahydro-β-carbolines
Gregor Haffer, Klaus Nickisch, and Ulf Tilstam*
*Process Research, Schering AG-Berlin, D-13342 Berlin, Germany
Abstract
A new mild and efficient method for the dehydrogenation of 3-carboxytetrahydro-β-carbolines using trichloroisocyanuric acid (TCCA) / triethylamine (TEA) has been developed.
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■ Two New Bicoumarins from a Citrus Plant
Shinobu Ikeda, Yuko Takemura, Motoharu Ju-ichi,* Chihiro Ito, and Hiroshi Furukawa
*Faculty of Pharmaceutical Science, Mukogawa-Women's University, 11-68 Koushien Kyuban-Cho, Nishinomiya, Hyogo 663-8179, Japan
Abstract
Two new bicoumarins, named biseselin (1) and yukomarin (3), were isolated from the roots of Yuko (Citrus yuko Hort. ex Tanaka) , and their structures were elucidated by spectroscopic analyses.
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■ Structures of Two New Cyclolanostanol Xylosides, Cimiacerosides A and B
Akiko Kusano, Masayuki Takahira, Makio Shibano, Toshio Miyase, Toru Okuyama, and Genjiro Kusano*
*Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
Abstract
A new cyclolanostanol xyloside, cimiaceroside A, was isolated from Cimicifuga acerina (Miyagi) and Actaea asiatica, and another, cimiaceroside B, from C. simplex and C. acerina (Oki) respectively. The absolute stereostructures of cimiacerosides A and B were determined as 20(S),22(R),23(S),24(R)-16β:23;22:25-diepoxy-3β,23,24-trihydroxy-9,19-cyclolanost-7-ene-3-O-β-D-xylopyranoside and 20(S),22(R),23(S),24(R)-16β:23;22:25-diepoxy-3β,23,24-trihydroxy-9,19-cyclolanostane-3-O-β-D-xylopyranoside on the basis of chemical and spectral data, and with the aid of a new version of Mosher’s method.
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■ The Regioselective Acylation Reactions of Imidazopyridines
Dennis J. Hlasta* and Marla J. Silbernagel
*Department of Medicinal Chemistry, Sanofi Winthrop Inc., Collegeville, Pennsylvania, 19426, U.S.A.
Abstract
The regioselectivity of acylation in imidazopyridines can be controlled by two mechanism-specific reactions. As expected acylation reactions under Friedel-Crafts conditions result in reaction at the most electron-rich site in imidazopyridines. However, depending on the structure of the imidazopyridine, ylid intermediates are proposed to direct reaction to the electron-deficient site in the parent heterocycles. These observations led to the selective synthesis of acylimidazopyridines and this methodology was used in the preparation of analogs of the α2-adrenergic agonists MPV-207 and clonidine.
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■ High Pressure in Enzyme Catalyzed Organic Reactions
Nobuya Katagiri,* Masahiko Yamaguchi,* and Chikara Kaneko
*Faculty of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan
Abstract
Adenosine deaminase and lipases catalyzed hydrolysis under high pressure were described. The hydrolysis by both enzymes was facilitated by high pressure. this technique was used for the kinetical resolution of racemic highly modified nucleosides having biological activities.