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. 51, No. 5, 1999
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■ Synthesis of 2,5-Heptano-1,2-dihydropyridine Derivatives
Volker Kirsche, Werner Tochtermann,* Eva-Maria Peters, Karl Peters, and Hans George von Schnering
*Institut für Organische Chemie, Universität Kiel, Olshausenstrasse. 40, D-24098 Kiel, Germany
Abstract
The title compounds have been synthesized by reaction of the dihydromethoxyoxepine (1) with hydrochiorides of amino esters (2a-2c) or of hydrazides (2d-2e) in the presence of sulfuric acid.
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■ Synthesis and Emission Behavior of Double-armed Tetrathiacrown Carrying Two Naphthalenes
Kanji Kubo,* Yoshihiro Miyazaki, Katsuhito Akutsu, and Tadamitsu Sakurai
*Departmnet of Applied Chemistry, Faculty of Engineering, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan
Abstract
Double-armed tetrathiacrown having two naphthalenes shows specific photophysical properties for Pd2+ and Au3+ ions selectively, based on cooperative actions of parent thiacrown and fluorometric side arms.
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■ Oxidation Activity of Long Conjugative and Metal-coordinative Flavin Model: Bent-Benzodipteridine
Hideki Ohshiro, Hirobumi Takahashi, Shin-ichi Kondo, Yumihiko Yano,* Masakazu Koga,* and Fumio Yoneda
*Faculty of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu 376-8515, Japan
Abstract
Redox behavior of 11,14-diethyl-3,8-dimethyl-1,3,5,6,8,10,11,14-octaazapentaphene-2,4,7,9 (14H,3H,8H,11H)-tetrone (bent-BDP) was studied in aqueous solution, and a metal ion effect was also examined for the oxidation of an NADH model in acetonitrile.
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■ A Shortcut and Stereoselective Synthesis of 1-β-Alkyl-2-deoxy-D-ribose Derivatives via Wittig-Horner-Emmons Reaction
Naoko Matsuura, Yoshitaka Yashiki, Shouji Nakashima, Minoru Maeda, and Shigeki Sasaki*
*Faculty of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
Abstract
A shortcut and stereoselective synthesis of 1-β-alkyl-2-deoxy-D-ribose derivatives has been achieved via Wittig-Horner-Emmons reaction followed by intramolecular 1,4-addition. After the systematic investigation of the effects of the base and the solvent, the best β-selectivity, as much as 12:1, was obtained with potassium tert-butoxide in THF.
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■ The Conversion of Mixed N,O-Diacylated 2-Aminophenols to 2-Substituted Benzoxazoles
Mark R. DeLuca, Irach B. Taraporewala, and Sean M. Kerwin*
*Division of Medicinal Chemistry, College of Pharmacy, The University of Texas at Austin, Austin, Texas 78712-1074, U.S.A.
Abstract
When N,O-diacylated 2-aminophenols that have different acyl substituents on nitrogen and oxygen are treated with p-toluenesulfonic acid in refluxing xylenes, mixtures of benzoxazoles are produced. The major product is the benzoxazole in which the substituent at the 2-position is derived from the acyl group on nitrogen. This product may arise from an unusual case of acid-mediated neighboring amido-group assisted hydrolysis.
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■ Novel Synthesis and Properties of [n](2,4)Pyridinophanes and [n](2,4)Quinolinophanes
Hideo Miyabara, Tohru Takayasu, and Makoto Nitta*
*Department of Chemistry, School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan
Abstract
A new short synthesis of cyclohexenone-annulated [n](2,4)pyridinophanes (n=9-7), which were easily converted to [n](2,4)quinolinophanes (n=9-7), respectively, was accomplished by the reaction of 3-amino-2-cyclohexenone with 2-cycloalkenones
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■ Preliminary Study of the Total Synthesis of Bao Gong Teng A Analogs Using 8-Benzyl-2-oxo-8-azabicyclo[3.2.1]oct-3-ene-6-endo/exo- and 7-endo/exo-carbonitrile
Stéphane Rézel, François Estour, Damien Canitrot, Elena V. Bejan Voinea, Jean-M. Chezal, Claire Lartigue, Yves Blache, Alain Gueiffier, Gérard Dauphin, Jean C. Teulade, and Olivier Chavignon*
*Département d'Analyse Structurale et de Pharmacologie, Laboratoire de Chimie Organique, Faculté de Pharmacie, Université d'Auvergne, 28, Place Henri Dunant, B.P. 38, 63001 Clermont-Ferrand Cedex, France
Abstract
The use of four cycloadducts from the Katritzky reaction for subsequent preparation of Bao Gong Teng A analogs was studied. We show that the reduction of 2-oxo-8-azabicyclo[3.2.1]octanes (1-4) to alcohols allows the 2-exo/endo isomerism to be exploited. The 7-endo compound (4) also yielded azatricyclo[5.2.l.04,8]decanone (12) from alcohol (11). When the nitrile was converted into an acetyl group, 6-endo products (13) and (14) were isornerized to 6-exo. Trimethylsilyloxy derivatives (13-18) ultimately yielded 2-hydroxy-azabicyclooctethanone (22-24). These results afford an approach to the synthesis of the 6-exo 2-endo, 7-exo 2-exo and 7-exo 2-endo isomers of Bao Gong Teng A.
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■ Reactivity of Heterocyclic Enaminones: Regioselective Synthesis of Some Pyridobenzodiazepines and Imidazopyridines
Yves Blache,* Mohammed Hichour, Genoveffa Di Blasi, Jean-Michel Chezal, Henri Viols, Olivier Chavignon, Jean-Claude Teulade, and Jean-Pierre Chapat
*E. A. 2414 Pharmacochimie et Biomolécules, Laboratoire de Chimie Organique Pharmaceutique, Université Montpellier I, 15 Avenue Charles Flahault, 34060 Montpellier, France
Abstract
Reactivity of enaminones derived from various diaminopyridines toward electrophilic carbons (imines, carbodiimides, isocyanates) is reported. The reactions leading to diazepinic or imidazolic ring systems are shown to be dependent of the electrophilic species as well as of the position of the nitrogen atom in the heterocyclic ring.
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■ Synthesis of Alkylthio- and Arylthioheteroarenes by Regioselective Grignard Reaction of Thiocyanatoheteroarenes
Izuru Nagasaki, Miyuki Matsumoto, Masanori Yamashita, and Akira Miyashita*
*Schol of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
Abstract
Treatment of thiocyanatoheteroarenes (1) with Grignard reagents (2) afforded alkylthio- or arylthioheteroarenes (3-6) in good yields. Grignard reagents regioselectively attacked the sulfur atom of the thiocyanato group owing to the metal-chelating effect of this group in combination with the hetero ring-nitrogen. 2-Thiocyanatopyridine (1a), 2-thiocyanatopyrimidine (1b), 2-thiocyanatobenzothiazole (1c), and 4-thiocyanatoquinazoline (1d) were converted into a variety of sulfides. Sulfides consisting of two heteroarenes linked by a sulfur atom were readily obtained by this method.
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■ Stereochemistry of Fluoride-promoted Protio-Desilylation of α-Thiasilanes
Vanda Cerè,* Francesca Peri, and Salvatore Pollicino
*Dipartimento di Chimica Organica "A Mangini", Universita degli Studi di Bologna, Viale Risorgimento, 4, I-40136 Bologna, Italy
Abstract
We have investigated the stereochemistry of fluoride-promoted protiodesilylation of α-thiasilanes on a rigid structure like the thiahydrindane, compound in which the stabilization of a negative charge on the carbon a to sulfur can be gradually increased from sulfide to sulfoxide and at last to sulfone. For the desilylation of sulfoxides and sulfones relatively free carbanions can be hypothesized, for sulfides the intermediate can probably be captured, to some extent stereospecifically, by an electrophile.
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■ Pyridazines, 89. On the Synthesis of Novel 1,2-Diazine Containing Tricyclic Systems: Preparation of Dipyridazinodiazepinones
Gottfried Heinisch, Elisabeth Huber, Barbara Matuszczak,* and Kurt Mereiter
*Institute of Pharmaceutical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria
Abstract
A synthetic method for the so far unknown dipyridazino[4,3-b:3’,4’-e][1,4]diazepinone system (7a) was elaborated. Cyclisation of 6-chloro-N-(3,6-dichloropyridazin-4-yl)-3-(4-methoxybenzylamino)-N-propylpyridazine-4-carbox-amide (5) under basic conditions was found to yield in addition to the expected compound (7a) an isomeric dipyridazino[3,4-b:3’,4’-e][1,4]diazepinone (7b) resulting from Smiles rearrangement. The 7a/7b ratio was found to be influenced by the nature of the base and the solvent.
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■ A One-Step Transformation of (S)-1-Benzoyl-3[(E)-dimethylaminomethylidene]-5-methoxycarbonylpyrrolidin-2-one into Quinolizinyl- and 2H-2-Pyranonyl-substituted Alanine Derivatives
Marko Skof, Jurij Svete,* and Branko Stanovnik*
*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, P.O. Box 537, SLO-1000 Ljubljana, Slovenia
Abstract
(S)-1-Benzoyl-3-[(E)-dimethylaminomethylidene]-5-methoxycarbonylpyrrolidin-2-one (1) was transformed in one step with various 1,3-dinucleophiles (2-14) into the corresponding N-benzoyl-3-quinolizinyl-(15-18) and N-benzoyl-3-(2H-2-pyranonyl)alanine methyl esters (19-27).
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■ Synthesis of [2.n]Thiophenophanes by Intramolecular [2+2] Photocycloaddition
Yosuke Nakamura, Masayoshi Kaneko, Teruo Shinmyozu, and Jun Nishimura*
*Department of Chemistry, Faculty of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu 376-8515, Japan
Abstract
[2.n](2,5)Thiophenophanes (n = 3–5) having a cyclobutane ring were successfully synthesized by the intramolecular [2 + 2] photocycloaddition of α,ω-bis(5-vinyl-2-thienyl)alkanes. The yields, conformation, and dynamic behavior of the thiophenophanes were significantly dependent on the oligomethylene chain length, n.
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■ Highly Enantioselective Synthesis of 3-Hydroxy-2-phenylpiperidine via the Sharpless AD-Reaction
Heinz Stadler* and Michael Bös
*Pharma Division, Pharma Preclinical Research & Development, F.Hoffmann-La Roche Ltd., Grenzacherstrasse 124, CH-4070 Basel, Switzerland
Abstract
Asymmetric dihydroxylation (AD) of the silyl enol ether (3) provided after hydrolysis the hydroxy ketone (4). Subsequent hydrogenation yielded the title compound (1) as a diastereomeric mixture. The cis-isomer is an important building block for the synthesis of potent NK1 receptor antagonists.
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■ Preparation of 1,4-Dioxenes from α-Diazo-β-ketoesters
Ramona Hilgenkamp, John B. Brogan, and Charles K. Zercher*
*Department of Chemistry, College of Engineering and Physical Sciences, Parsons Hall, University of New Hampshire, Durham, NH 03824, U.S.A.
Abstract
A novel preparation of 1,4-dioxenes is reported in which a rhodium carbenoid generated from an α-diazo-β-ketoester reacts with a 1,2-diol. Insertion of the carbenoid into the O-H bond followed by hemiacetal formation and acid-catalyzed dehydration generates the targeted 1,4-dioxene.
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■ Alternative Synthesis of Tryptophan Pseudodipeptides
Valérie Marcq, Catherine Mirand,* Hervé Emonard, and William Hornebeck
*Facluté de Pharmacie, UPRES-A/CNRS 6013, Insitut des Biomoleculés, 51, rue Cognacq-Jay, F-51096 Reims Cedex, France
Abstract
The tryptophan pseudodipeptides (8) and (13) were synthesized via generation of the tryptophan backbone through the reaction of a succinylaminomalonate with a quaternarized gramine.
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■ A New Approach to 5H-Pyrrolo[3,2-d]pyrimidines (9-Deazapurines) from 3-Aminopyrrole-2-carboxylates
Lovro Selic and Branko Stanovnik*
*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, P.O. Box 537, SLO-1000 Ljubljana, Slovenia
Abstract
3-Arnino-4-ethoxycarbonyl-1-methyl-1H-pyrrole-2-carboxylate (2) was used to prepare 9-deazapurines in a single step reaction.
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■ Synthesis and Spectroscopic Properties of 9-Substituted Benz[g]indoles
Yoshinobu Nagawa,* Koichi Honda, and Hiroshi Nakanishi
*National Institute of Bioscience and Human-Technology, 1-1, Higashi, Tsukuba, Ibaraki, 305-8566, Japan
Abstract
Photolysis of 1,1’-(1,8-naphthylene)di-1H-1,2,3-triazoles in methanol has given new benz[g]indoles with a triazole ring at 9-position. Similar photoreaction of 1-(8-dimethylamino-1-naphthyl)-1H-1,2,3-triazoles also gives new benz[g]indoles with a dimethylamino group at 9-position. The spectral properties of these compounds were studied in comparison with those of corresponding benz[g]indoles obtained from the similar photolysis of 1-(1-naphthyl)-1H-1,2,3-triazoles. Since the substituent at 9-position and the pyrrole moiety exist in close proximity, unique properties such as the strong intramolecular hydrogen bonding and the restricted rotation of C(sp2)-N(sp3) bond are observed in the 9-substituted benz[g]indoles.
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■ Synthesis of 2-Amino-4-aryl-3-cyano-6-methyl-5-ethoxycarbonyl-4H-pyrans
Anatoliy M. Shestopalov,* Zukhra I. Niazimbetova, Dennis H. Evans,* and Murat E. Niyazymbetov
*Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, U. S. A.
Abstract
A one-step electrochemical synthesis of the title compounds has been devised. The starting materials are aromatic and heteroaromatic aldehydes, malononitrile and ethyl acetoacetate. The overall reaction is catalyzed by electrogenerated base (EGB) formed at a platinum cathode in acetonitrile.
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■ 3',4-Dialkylthio-3,4'-diquinolinyl Sulfides with Nonidentical Alkyl Groups
Malgorzata Nowak, Krystian Pluta,* Malgorzata Szmielew, Maria J. Maslankiewicz, and Andrzej Maslankiewicz
*Department of Organic Chemistry, The Medical University of Silesia, Jagiellonska Str. 4, 41-200 Sosnowiec, Poland
Abstract
3’,4-Dialkylthio-3,4’-diquinolinyl sulfides (6) were obtained by three methods in the reaction of thioquinanthrene (1) with sodium hydrosulfide followed by sequential S-alkylation of the 3- and 4-thiolate functions. Competitive S-alkylation of 3- and 4-qui-nolinethiolates (4) and (10) in DMSO showed three times greater susceptibility of the 3-thiolate function to the alkylating agent than the 4-thiolate function. 4-Quinolinethio-lates (3) were converted into 4(1H)-quinolinethiones (8).
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■ Synthetic Studies on Trifluoroacetylindoles
Hitoshi Takami, Hirokazu Koshimura, and Toshiaki Kumazawa*
*Pharmaceutical Research Institute, Kyowa Hakko Kogyo Co., Ltd., Nagaizumi, Shizuoka, 411-8731, Japan
Abstract
Trifluoroacetylindoles were obtained regioselectivcly through the reaction of indolylorganometallic species, prepared by halogen-metal exchange or direct metalation of N-substituted or -nonsubstituted indoles, with TFAA in good yield
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■ Total Synthesis of (±)-Deethyleburnamonine and Vindeburnol (RU 24722) with the Corresponding Nitriles as Starting Material
Mauri Lounasmaa,* David Din Belle, and Arto Tolvanen
*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, P.O. Box 6100, FIN-02150 HUT Espoo, Finland
Abstract
Cyclisation occurred during base treatment of cis-nitrile (5). The resulting new imine (6) was converted into the therapeutically important deethyleburnamonine (4). Total synthesis of vindeburnol (RU 24722) (3), another important drug, was achieved in one step starting from the trans-nitrile (9).
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■ A New Synthesis of Psilocin
Hideki Sakagami and Kunio Ogasawara*
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
A new route to the hallucinogenic alkaloid psilocin, isolated from the mushroom species Psilocybe mexicana, has been established.
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■ Michael Reactions of β-Keto Phosphonates with Arylmethylene-malononitriles: The First Synthesis of Densely Functionalized 5-Diethylphosphinyl-2-amino-4H-pyrans
José L. Marco* and Pilar M. Chinchón
*Laboratorio de Radicales Libres, Instituto de Química OrgÁnica General , C. S. I. C., Calle Juan de la Cierva 3, E-28006 Madrid, Spain
Abstract
A convenient synthesis of densely functionalized derivatives of 5-diethylphosphinyl-2-amino-4H-pyrans (1a-d) is described for the first time.
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■ The Chemistry of Nx,Ny,Nz-Trimethyladenines and More Highly N-Methylated Adenines
Tozo Fujii* and Taisuke Itaya
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Various tri- and poly-N-substituted adenines are represented by the corresponding positional isomers of Nx, Ny, Nz-trimethyladenine and of more highly N-methylated adenines. The chemistry of known isomers of these tri- and poly-N-methylated adenines is reviewed with 120 reference citations.