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. 55, No. 12, 2001
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■ Synthesis of Novel Oxazoline Ligands Designed for Attachment to Gold Nanoparticles
Jeffrey T. Banks,* Karen M. Button, Robert A. Gossage,* Tamara D. Hamilton, and Kurt E. Kershaw
*The Chester Woodleigh Small and David Upton Hill Laboratories of Organic and Inorganic Chemistry, 6 University Avenue Department of Chemistry Elliott Hall, Acadia University, Wolfville, Nova Scotia, B0P 1X0, Canada
Abstract
The synthesis of new modified 2-aryloxazoline ligands is described. The aromatic portion of the oxazoline has been appended with an amide linked thioctic acid derived group that is designed to facilitate attachment of the ligand to gold nanoparticles. This represents the first examples of ligands within the class of monodentate oxazolines that have been modified for this specific function.
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■ Synthesis of 3-Methylthio-4-aryl-3-pyrroline-2,5-diones and 3-Arylpyrrolidine-2,5-diones by Reaction of Nitroketene Dithioacetal with Arylacetonitriles
Yasuhiro Shigemitsu and Yoshinori Tominaga*
*Industrial Technology Center of Nagasaki, 2-1303-8, Omura, Nagasaki, 856-0026
Abstract
The reaction of nitroketene dithioacetal (1a), i.e., 2,2-bis(methylthio)-1-nitroethylene, with arylacetonitriles (2a-I) in the presence of the base like sodium hydroxide gave 4-nitrobut-2-enenitriles (3a-I) which were converted into 5-hydroxyimino-4-methylthio-3-phenyl-3-pyrrolin-2-ones (4a-i) under refluxing in methanol. Title compounds (5a-i) were readily obtained by the treatment of 4a-i with hydrochloric acid and were finally led to N-methylated products (6a-I) with methyl iodide. The reduction of maleimides (4 - 6) with zinc dust in acetic acid afforded the corresponding 3-arylpyrrolidine-2,5-diones (7a-i) that can be converted to pharmacologycally active compounds like mesembrines.
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■ A Novel Acylated Pelargonidin 3-Sophoroside-5-glucoside from Greyish-Purple Flowers of the Japanese Morning Glory
Kenjiro Toki, Norio Saito, Shigeru Iida, Atsushi Hoshino, Atsushi Shigihara, and Toshio Honda*
*Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
A novel acylated anthocyanin was isolated from greyish-purple flowers of a dingy mutant in the Japanese morning glory (Pharbitis nil or Ipomoea nil) with three known pigments as main pigments. This novel pigment was determined to be pelargonidin 3-O-[2-O-(β-D-glucopyranosyl)-6-O-(trans-4-O-(β-D-glucopyranosyl)caffeoyl)-β-D-glucopyranoside]-5-O-β-D-glucopyranoside (3), and the other three pigments (1, 2, and 4) were 3-sophoroside-5-glucosides of pelargonidin and peonidin, and peonidin 3-O-[2-O-β-D-glucopyranosyl-(6-O-(β-D-glucopyranosylcaffeoyl)-β-D-glucopyranoside]-5-O-β-D-glucopyranoside. In addition, pelargonidin 3-sophoroside and pelargonidin 3-glucoside were also detected as main pigments in two other mutants, duskish-1 and duskish-2, displaying pale-purple hue flowers.
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■ Enantioselective Synthesis of (S)-2,3,9,10,11-Pentamethoxyhomoprotoberberine, and (S)-O-Methylkreysigine Using an Asymmetric Addition to an Isoquinoline Ring
Kazuhiro Nagata, Takashi Itoh, Keiko Kameoka, Michiko Miyazaki, and Akio Ohsawa*
*School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
Abstract
Total synthesis of (S)-2,3,9,10,11-pentamethoxyhomoprotoberberine (7) was carried out using an asymmetric nucleophilic addition of a silyl enol ether to 5,8-dibromo-6,7-dimethoxyisoquinoline (1) in the presence of an acid chloride derived from alanine. The addition proceeded in high diastereoselectivity to give a 1-substituted 1,2-dihydroisoquinoline (2), which was converted to the target alkaloid in short steps. One of the intermediates was readily transformed to a product (8) which was known as a precursor for synthesis of O-methylkreysigine (9).
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■ Mono and Sequential Bis Solid Phase Alkylations of a (R)-Phenylglycinol Derived Pyrrolidinone Scaffold
Armand Blommaert, Philippe James, Fanny Valleix, Henri-Philippe Husson, and Jacques Royer*
*Laboratoire de Chimie Thérapeutique associé au C.N.R.S., Faculté des Sciences Pharmaceutiques et Biologiques, Université René Descartes, 4, avenue de l'Observatoire 75270 Pairs Cedex 06, France
Abstract
The preparation of piperidine- and pyrrolidinone-like polymer supported (R)-phenylglycinol derived scaffolds is described. Alkylation reactions were performed as a model transformation of these templates on the solid support which highlight some specific limitations in the use of (R)-phenylglycinol on the resin. Whereas the polymer supported piperidine was completely void of reactivity, alkylation of the pyrrolidinone counterpart proceeded with good yield, purity and control of mono- over bis-alkylation but with low diastereomeric excess.
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■ Novel and Efficient Synthesis of 8-Oxoadenine Derivatives
Kosaku Hirota,* Kazunori Kazaoka, Itaru Niimoto, and Hironao Sajiki
*Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan
Abstract
A novel synthetic method of 8-oxoadenine derivatives (3 and 4) is reported. This widely applicable synthetic method was realized through the use of 5-amino-4-cyano-2-oxoimidazole derivatives (2) as the key intermediates. A variety of substituents were successfully introduced to the 2- and 9-position of the 8-oxoadenine nucleus.
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■ A Facile Synthesis of 4(3H)-Pyrimidinones via [4+2] Cycloaddition Utilizing Trimethylsilylketene
Shigeru Arai, Takuya Sakurai, Hitomi Asakura, Shin-ya Fuma, Takayuki Shioiri,* and Toyohiko Aoyama*
*Graduate School of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
Abstract
The [4+2]cycloaddition reaction utilizing trimethylsilylketene with 1,3-diaza-1,3-dienes smoothly proceeded to give the desired cycloadducts, 4(3H)-pyrimidinones, in moderate to high yields.
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■ Regioselective ortho-Directed Metalation and Electrophilic Substitution of Indole- and Indoline-5-(N-phenyl)carboxamides
Jean-François Rousseau and Robert H. Dodd*
*Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, Avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France
Abstract
Treatment of 1-(N,N-dimethylsulfamoyl)-1H-indole-5-(N-phenyl)carboxamide (1) with s-butyllithium at -80°C in THF followed by addition of an electrophile gave exclusively the product of C-2 substitution. A second metalation-substitution cycle on this product led to incorporation of the electrophile exclusively at C-4. In the case of the analogous indoline derivative (2), the first o-metalation occurred at C-4 while C-6 was the site of the second o-metalation.
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■ Novel Formaldehyde-mediated Dimerization Reaction of N-Alkyl-1-naphthylamine Derivatives under Mild/Neutral Conditions; Application to Synthesis of Naphthylamine-derived Macrocycles
Hiroyasu Takahashi, Yuichi Hashimoto, and Kazuo Nagasawa*
*Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
Abstract
The dimerization reaction of N-methyl-1-naphthylamine (1) with formaldehyde is described. Reaction of 1 with formaldehyde under mild/neutral conditions gave bis-4-(1-N-methylaminonaphthyl)methane (2) in high yield as a single dimerization product. This formaldehyde-mediated aromatic condensation reaction is chemo- and regio-selective, and it takes place particularly with N-monoalkyl-1-naphthylamines as substrates. The novel naphthylamine-derived macrocyclic compounds 1,6,28,33-tetraaza-[6.1.6.1]paranaphthalenophane (13a) and 1,13-diaza[13,1]paranaphthaleno-phane (12c) were synthesized by application of this formaldehyde-mediated mild/neutral condensation reaction as the key step.
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■ Photoreactions of 3-Tosyl- and 6-Tosyl-dihydro-1,3-diazaazulanones to Form 1,3-Diazaazulanones and Ionic Pairs between p-Toluenesulfonate Anion and 1,3-Diazadihydroazulanone Cations
Katsuhiro Saito,* Tomoko Kunisada, Hiroyuki Ishiguro, Michie Sato, and Tadayuki Doi
*Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan
Abstract
A solvent effect was found on the photoreactions of 1-aryl-3-tosyldihydro-1,3-diazaazulanones with a low pressure mercury lamp. Thus, ion pairs between p-toluenesulfonate anion and the corresponding 1-aryl-1,3-diazadihydroazulanone cations were afforded by the reactions in THF. On the other hand, the corresponding 1-aryl-1,3- diazaazulanones were formed by the reactions in the other solvents. The analogous photoreactions with 1-aryl-6-tosyldihydro-1,3-diaza-azulanones afforded the corresponding 1-aryl-1,3-diazaazulanones
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■ Hammett Type Correlations for Intramolecular Charge Transfer (ICT) Dipole Moments of 4’-Substituted 9-Styrylacridines in the Ground State and in the Excited State
Mohamed El Azami, Najib Bitit,* Abdelali Kerbal, Souad Lahlou, Saadia Aït Lyazidi, Jean-Pierre Desvergne, Henri Bouas-Laurent,* and Dario Bassani
*Laboratoire de Chimie Organique et Organometallique, CNRS UMR 5802, Université Bordeaux, I, 351 cours de la Libération, 33405 Talence Cedex, France
Abstract
9-Styrylacridine (1a) and a series of 4’-substituted 9-styrylacridines (1b-f) (substituent : Me, OMe, NMe2, Cl, NO2) have been prepared to study their spectroscopic properties in several solvents of different dipolarity. They show strong Stokes shifts from the ground state to the S1 excited state (Δν = - 5400 to - 8700 cm-1) which denotes an important change of conformation in the fluorescing state. AM1 calculations suggest that the coplanarity increases in the S1 state. The fluorescence spectra exhibit a positive solvatochromism, allowing the determination of excited state dipole moment (μE). Hammett correlations between σπ and μG (ground state dipole moments) and μE respectively, show that the electronic influence of substituent on the internal charge transfer (ICT) is ca. 3 times stronger in the S1 excited state than in the ground state.
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■ Three New Isoflavonoids from Erythrina variegata
Hitoshi Tanaka,* Miyuki Hirata, Hideo Etoh, Naoharu Watanabe, Hiroshi Shimizu,
Mansoor Ahmad, Zahid Khan, and Munir Anwar
*Faculty of Pharmacy, Meijo University, 150 Yagoto, Tempaku-ku, Nagoya, Aichi 468-8503, Japan
Abstract
Three new isoflavonoids, eryvarins C-E, together with fourteen known compounds were isolated from the roots of Erythrina variegata (Leguminosae) and their structures were elucidated on the basis of spectroscopic evidence
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■ Direct Modification of Benzoannelated Crown Ethers with 1,2,4-Triazin-5(2H)-one Moieties
Gennady L. Rusinov, Dmitry G. Beresnev, Nadezhda A. Itsikson, and Oleg N. Chupakhin*
*Institute of Organic Synthesis, Urals Division, Russian Academy of Sciences, 20, S. Kovalevskaya st., Yekaterinburg, GSP-147, 620219 , Russia
Abstract
A convenient method for one-step coupling of benzoannelated crown ethers with 1,2,4-triazinones based on the reaction of nucleophilic addition to unsubstituted carbon atom of the triazine ring has been worked out. It has been shown that the reaction of 3-substituted 1,2,4-triazin-5(2H)-ones (1) with benzocrown ethers (benzo-12-crown-4, benzo-15-crown-5, benzo-18-crown-6) in the presence of acetic or trifluoroacetic anhydride is accompanied by acylation of triazine ring and results in formation of 3-(1-acyl-5-oxo-1,4,5,6-tetrahydro-1,2,4-triazin-6-yl)benzocrown ethers (7-12). The latters were converted to 3-(5-oxo-2,5-dihydro-1,2,4-triazin-6-yl)benzocrown ethers (18-20) using two alternative routes: the elimination of acetic or trifluoroacetaldehyde or the deacylation followed by the oxidation of the 1,4,5,6-tetrahydro derivatives (13-15).
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■ Simple Syntheses of Analogs of a Wasabi Phytoalexin
Fumio Yamada, Koji Yamada, Hikari Takeda, and Masanori Somei*
*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Preparations of 5-nitroindol-1-yl (5a), 6-nitroindol-1-yl (5b), and 1,2,3-benzotriazol-1-yl 1-methoxyindole-3-carboxylates (9) are reported. These are active esters and proved to be useful intermediates for the preparations of ester and amide analogs of methyl 1-methoxyindole-3-carboxylate, a wasabi phytoalexin.
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■ Synthesis of 1H-[1]Benzopyrano[4,3-b]pyrrole and 4H-Thieno[3,2-c][1]benzopyran Derivatives. Functionalisation by Aromatic Electrophilic Substitution
Rocío Álvaro Navarro, Luis Calvo Bleye, Alfonso González-Ortega,* and M. Carmen Sañudo Ruíz
*Deparamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, 47005 Valladolid, Spain
Abstract
4,4-dialkyl-1H-[1]benzopyrano[4,3-b]pyrroles were prepared starting from [1]benzopyrano[4,3-b]pyrrol-4(1H)-ones and organometallic reagents. Subsequently, both types of polycyclic compound and their analogous 4H-thieno[3,2-c][1]benzopyrano derivatives were functionalized at C-2 by aromatic electrophilic substitution (bromination, nitration, acetylation and formylation).
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■ Synthesis of 6-Bromo-4-methylbenzofuroxan
Tohru Takabatake,* Aki Takei, Tomoyuki Miyazawa, Minoru Hasegawa, and Shinichi Miyairi
*College of Pharmacy, Nihon University, 7-7-1 Narashinodai, Funabashi-shi, Chiba
274-8555, Japan
Abstract
6-Bromo-4-methylbenzofuroxan (3) was prepared by the thermal decomposition of 4-bromo-2-methyl-6-nitrophenylazide in excellent yields. 1H-NMR spectra showed that the compound (3) rapidly rearranges between the two unsymmetrical bicyclic structures. However, the methyl group and bromine may possibly function as a barrier against molecular rearrangement and so molecular rearrangement is slow enough that different chemical shifts are apparent at room temperature.
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■ Bidirectional Conversion of Galanthamine and Crinine Type Heterocycles
Matthias Treu, Stefan Welzig, and Ulrich Jordis*
*Institute of Organic Chemistry, Vienna University of Technology, Getreidemarkt 9/154, A-1060 Vienna, Austria
Abstract
The conversion of galanthamine-type molecules into crinine-type compounds and vice versa has been accomplished by a ring opening-Michael addition-cascade of a galanthamine-type secondary amine and a crinine-type quarternary ammonium salt.
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■ Dippinines A - D, New Iboga-derived Indole Alkaloids from Tabernaemontana
Toh-Seok Kam* and Kooi-Mow Sim
*Department of Chemistry, Unviersity of Malaya, Pantai Valley, 50603 Kuala Lumpur, Malaysia
Abstract
Four new indole alkaloids, viz., dippinines A - D, belonging to the chippiine group were isolated from the leaf and stem extract of Tabernaemontana corymbosa and the structures established by spectroscopic analysis.
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■ Conjugate Addition Reactions of Some Methylidene 1-Benzylpyrimidinetrione Derivatives
Essam Abdelghani
*Chemistry Department, College of Science, King Khalid Universitya, P.O. Box 9004, [97], Abha, Saudi Arabia
Abstract
1-Benzyl-2,4,6-pyrimidinetrione (1) reacts at C-5 with aldehydes and the isolated products can easily undergo base-induced transformations by Michael addition. On the contrary,the action of POCl3 or piperidine/AcOH on the title trione afforded pyrimido[4',5':4,5]furo[2,3-d]pyrimidine (16) and a dimer (17), respectively, which in turn, undergo cyclocondensation in Ac2O.
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■ An Improved Method for the Preparation of 4,7-Dioxo-4,7-dihydrobenzo[b]thiophene-2-carboxylates from 2-Acyl-1,4-benzoquinones and Mercaptoacetates
Kazuhiro Kobayashi,* Keiichi Yoneda, Masaharu Uchida, Hideki Matsuoka, Osamu Morikawa, and Hisatoshi Konishi
*Department of Materials Science, Faculty of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan
Abstract
4,7-Dioxo-4,7-dihydrobenzo[b]thiophene-2-carboxylates (4) have been synthesized in a one-pot procedure from 2-acyl-1,4-benzoquinones (1) and mercaptoacetates (2) by using 1-trimethylsilylimidazole as a protective reagent as well as a base. Thus, reaction of 1 with 2 in THF at room temperature was followed by treatment with excess of 1-trimethylsilylimidazole at 80 °C. Then the cooled mixture was hydrolyzed with hydrochloric acid and oxidized with cerium(IV) ammonium nitrate (CAN) to give the expected thiophenequinone derivatives (4). 4,9-Dioxo-4,9-dihydronaphtho[2,3-b]thiophene-2-carboxylates (7) were similarly prepared from 2-acyl-1,4-naphthoquinones (5) and mercaptoacetates, in general, by omitting the CAN oxidation procedure.
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■ A Sojourn in the Synthesis and Bioactivity of Diindolylalkanes
Manas Chakrabarty,* Ramkrishna Basak, and Yoshihiro Harigaya
*Department of Chemistry, Bose Institute, 93/1, A. P. C. Road, Kolkata-700009, India
Abstract
The different synthetic routes to diindolylalkanes (DIAs), an important class of synthetic and natural products, their merits and demerits and the properties of the bioactive DIAs have been presented in this review which is the first of its kind in this field. The synthesis of the bioactive DIAs (3), streptindole (4), vibrindole A (6), 10 and 11 has also been included in this review