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. 1, 1998
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■ p-Methoxybenzyl Group as a Protecting Group of the Nitrogen in Indole Derivatives: Deprotection by DDQ or Trifluoroacetic Acid
Yasuyoshi Miki,* Hiroko Hachiken, Yoshimi Kashima, Wakiko Sugimura, and Norihide Yanase
*Faculty of Pharmaceutical Sciences, Kinki University, 3-4-1, Kowakae, Higashi-Osaka 577-8502, Japan
Abstract
Deprotection of 9-p-methoxybenzylcarbazole with DDQ gave a carbazole. However, methyl 1-p-methoxybenzylindole-2-carboxylate and dimethyl 1-p-methoxybenzyl-2,3-indoledicarboxylate were treated with TFA to yield the corresponding methyl indole-2-carboxylate and dimethyl indole-2,3-dicarboxylate.
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■ Synthesis of Both Enantiomers of Four Different Macrocyclic Lactones
Yoshihiro Noda* and Hitoshi Kashin
*Department of Industrial Chemistry and Engineering, College of Engineering, Nihon University, Tamura-machi, Koriyama, Fukushima, 963-8642, Japan
Abstract
Both enantiomers of macrocyclic lactones, 12-tridecanolide (1), 13-tetradecanolide (2), 14-pentadecanolide (3) and 15-hexadecanolide (4), were synthesized utilizing (S)-(-)-β-hydroxythioacetal (5) as the chiral building block. Key steps are the C-alkylation of a dianion derived from 5 with alkyl dibromides followed by conversion of functional groups and the two macrolactonization. The both enantiomers of 1-4 have been obtained by reductive desulfurization of the dithiane moiety.
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■ The Anomalous Stille Reaction of 5-Stannylimidazole with 3-Iodoindole
Tominari Choshi, Shiho Yamada, Junko Nobuhiro, Yukiko Mihara, Eiichi Sugino, and Satoshi Hibino*
*Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292, Japan
Abstract
Palladium(0)-catalyzed cross-coupling reaction of 5-stannylimidazole with 3-iodoindole gave two products including unexpected cine substitution.
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■ A Novel Nucleophilic Addition to α-Fluoro-α-trifluoromethyl-γ-lactones
Ken-ichi Ogu, Yusuke Saito, Motohiro Akazome, and Katsuyuki Ogura*
*Department of Applied Chemistry, Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
Abstract
α-Fluoro-β-(p-tolylsulfonylmethyl)-α-trifluoromethyl-γ-lactones (2) show high reactivity for various nucleophiles to afford cyclic hemiketals (3). Reduction of 3 with lithium aluminium hydride brought about reductive ring-opening to give 2-fluoro-3-(p-tolylsulfonylmethyl)-2-(trifluoromethyl)alkane-1,4-diols (4) in a stereoselective manner.
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■ Glycosidation of Glycosyl Phosphoramidites
Deqiang Niu, Meijin Chen, Hao Li, and Kang Zhao*
*Department of Chemistry, Faculty of Arts and Science, New York University, 29 Washington Place, New York, NY 10003-6617, U.S.A.
Abstract
A highly stereocontrolled 1,2-trans glycosidation reaction has been developed by using glycopyraosyl phosphoramidites as glycosyl donors in the presence of TMSOTf or BF3-OEt2 as a promoter in a variety of solvents.
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■ Selective Formation of 1-Azetine Derivatives via 1,3-Photoacyl Migration of Substituted α-Dehydrophenylalanines
Kanji Kubo,* Masaomi Koshiba, Hideki Hoshina, and Tadamitsu Sakurai*
*Departmnet of Applied Chemistry, Faculty of Engineering, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan
Abstract
Irradiation of (Z)-N-substituted benzoyl-α-dehydrophenylalanines in methanol with Pyrex-filtered light was found to selectively give 1-azetine derivatives, which may be derived from 1,3-acyl migration of the excited-state (E)-isomer, whereas no 1,5-acyl shift of the (Z)-isomer occurred owing to the stereoelectronic effects of the bulky aromatic acyl substituent.
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■ Oxazolo[4,5-g]-β-carbolines and Pyrazino[2,3-g]-β-carbolines. Synthesis of Modulators of the GABAA/Chloride Channel Complex
Preben H. Olesen,* Dieter Seidelmann, and John Bondo Hansen
*Medicinal Chemistry Research, Health Care Chemistry, Health Care Discovery & Development, Novo Nordisk A/S, Novo Nordisk Park DK 2760 Maaloev, Denmark
Abstract
The synthesis of oxazolo[4,5-g]-β-carbolines and pyrazino[2,3-g]-β-carbolines starting from 6-hydroxy-β-carbolines was investigated in order to prepare new ligands for the benzodiazepine site of the GABAA/chloride channel complex.
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■ The Reaction of Unsaturated Carbonyl Compounds with "Activated" Sulfur (II). Formation of Cyclic Disulfide and Polysulfides
Ugo Chiacchio, Antonino Corsaro, Venerando Pistarà, Giovanni Purrello,* and Antonio Rescifina
*Dipartimento di Scienze Chimiche, Università di Catania, Viale A. Doria 6, I-95125 Catania, Italy
Abstract
From the reaction of cinnamylideneacetophenone (1), sulfur and triethylamine in suitable solvents at room temperature, phenyl{3-[(E)-1-((5-benzoyl-3H-1,2-dithiol-3-ylidene)phenylmethyldisulfanyl)-1-phenylmethylidene]-3H-1,2-dithiol-5-yl}methanone (7) was isolated together with two polysulfurated compounds to which structures of phenyl(7-phenyl-1,2,3-trithiepin-4-yl)methanone (12) and phenyl(8-phenyl-1,2,3,4-tetrathiocin-5-yl)methanone (13) were assigned. The obtaining of these new products allows to complete the sequence of the whole process.
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■ Synthesis of 7,12-Dihydro-12-phenyl-5H-6,12-methanodibenz[c,f]azocines via N,N-Dibenzylphenacylamines
Necdet Coskun* and Levent Büyükuysal
*Uludag University, Department of Chemistry, 16059-Bursa, Turkey
Abstract
N,N-Dibenzylphenacylamines (1) were prepared in high yields by a one-pot reaction and cyclized at room temperature to give 7,12-dihydro-12-phenyl-5H-6,12-methanodibenz[c,f]azocines in high yields. 95% H2SO4 or 70% HClO4 was used as cyclization catalysts. The double-cyclization proceeds smoothly in the cases where electron-donating groups are present in both benzene ring. N-2,3-Dimethoxybenzyl-N-benzylphenacylamine (1f) gave the corresponding N-benzyl-1,2-dihydro-4-phenylisoquinoline on treatment with 95% H2SO4 while N-3,4-dimethoxybenzyl-N-benzylphenacylamine (1a) at the same reaction conditions and reaction time cyclized to the corresponding dibenzazocine. However 1a gave the corresponding dihydroisoquinoline which disproportionates to give N-benzyl-1,2,3,4-tetrahydro-4-phenylisoquinoline and N-benzyl-4-phenylisoquinolinium when treated with 70% perchloric acid at room temperature.
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■ Thermolysis of Selenophene 1,1-Dioxides
Takashi Umezawa, Tomoki Matsui, Yoshiaki Sugihara, Akihiko Ishii, and Juzo Nakayama*
*Department of Chemistry, Faculty of Science, Saitama University, Saitama, Saitama 338-8570, Japan
Abstract
Selenophene 1,1-dioxides are thermally far labile than the corresponding thiophene 1,1-dioxides. Even heavily substituted tetraphenylselenophene 1,1-dioxide (1a) decomposed, by a process not involiving cyclodimerization, when heated above its melting point or heated in refluxing toluene. Thus, the thermolysis of 1a in refluxing toluene afforded tetraphenylselenophene (2a, 6%), tetraphenylfuran (3a, 71%), (Z)-1,2,3,4-tetraphenyl-2-butene-1,4-dione (Z-4a, 19%), (E)-1,2,3,4-tetraphenyl-2-butene-1,4-dione (E-4a, 4%), SeO2 (23%), and Se (22%), while that of the neat sample gave 2a (5%), Z-4a (78%), E-4a (17%), SeO2 (17%), and Se (29%). Similar results were also obtained on thermolyses of a series of selenophene 1,1-dioxides. The experimental observations (influence of solvents, oxygen, and additive such as diene to the decomposition rate and the presence of induction period) revealed that the mechanism of the decomposition is highly complex. A tentative mechanism that can explain the observed products is presented.
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■ Synthesis of 4-Amino-3-quinolinesulfonic Acids and 4-Aminoquinolines
Leszek Skrzypek
*Department of Organic Chemistry, The Medical University of Silesia, Jagiellonska Str. 4, 41-200 Sosnowiec, Poland
Abstract
The hydrolysis of 4-chloro-3-quinolinesulfonyl chloride (1) gives 4-chloro-3-quinolinesulfonic acid (2) or 1,4-dihydro-4-oxo-3-quinolinesulfonic acid (3). Compound (2) reacts with primary and secondary aliphatic or primary aromatic amines to give 4-amino-3-quinolinesulfonic acid (4). Desulfonation of quinolinesulfonic acids (2,3,4) yields 4(1H)-quinolinone or 4-aminoquinolines (5).
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■ Synthesis and Confirmation of the Structures of Polonicumtoxins A, B and C
Mari Yotsu-Yamashita, Takeshi Yasumoto,* and Viresh H. Rawal*
*Faculty of Agriculture, Tohoku University, 1-1, Tsutsumidori, Amamiya, Aoba-ku, Sendai, 981, Japan
Abstract
Total syntheses of polonicumtoxins A (1), B (2), and C (3) have been completed. The key step of the syntheses involves and aza-Wittig reaction for the construction of the cyclic ketimine. The synthetic compounds were found to be identical in all respects with the natural products, thus confirming their assigned structures.
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■ A Convenient Synthetic Method for Fluorine-containing Benzo[h]quinolines from 2,4-Bis(trifluoroacetyl)-1-naphthylamine and Ketones
Etsuji Okada,* Norikado Tsukushi, Ting-Kai Huang, Hiroshi Tone, Nobuhiro Gotoh, Hiroshi Takeuchi, and Masaru Hojo
*Department of Chemical Science andd Engineerring, Faculty of Engineering, Kobe University, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
Abstract
2,4-Bis(trifluoroacetyl)-1-naphthylamine (1) reacted easily with various ketones in the presence of aqueous ammonia or triethylamine to afford 6-trifluoroacetyl-4-trifluoromethylbenzo[h]quinolines (2) in moderate to excellent yields.
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■ Synthesis of Indole-fused 4-Pyridone-3-carboxylic Acids
Ho Joon Song, Min Yi Kim, Soon Bang Kang, Bong Young Chung, and Youseung Kim*
*Biochemicals Reserach Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 131-650, Korea
Abstract
Some indole-fused tri- and tetracyclic 4-oxopyridine-3-carboxylic acids, quinolone-type derivatives, (3), (4) and (5) have been prepared. The synthesis is characterized by the construction of the pyridone ring through the intramolecular nucleophilic displacement cyclization at the 2-position of 3-substituted 1-methoxyindole accompanied with demethoxylation.
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■ Alkyl-substituted Benzo[1,2-d:3,4-d' ]diimidazoles. Preparation and Annular Tautomerism
Shuntaro Mataka,* Kazuchika Isomura, Tsuyoshi Sawada, Takehito Tsukinoki, Masashi Tashiro, Kazufumi Takahashi, and Akiyoshi Tori-i
*Instituete of Advanced Material Study, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan
Abstract
The treatment of 4-nitro-5-amino-2,1,3-benzothiadiazole (3) with tin/hydrochloric acid in the presence of a carboxylic acid having a C1-C3 chain gave the corresponding 2,5-dialkylbenzo[1,2-d:3,4-d’]diimidazoles (1). When the amount of tin was reduced to a half, 3 afforded only 5-alkylimidazolo[4,5-d]benzothiadiazoles (2). Unsymmetrical dialkyldiimidazoles (1) were obtained from 2 in a second step. Annular tautomers due to NH-proton exchange of the imidazole rings of 1 and 2 could be observed in 1H NMR spectra in DMSO-d6 at a low concentration (ca. 5 x 10-4M).
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■ New Briarane Diterpenes from a Gorgonacean Briareum Sp.
Tetsuo Iwagawa,* Naoki Takenoshita, Hiroaki Okamura, Munehiro Nakatani,* Matsumi Doye, Kozo Shibata,* and Motoo Shiro*
*Faculty of Science, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065, Japan
Abstract
Two new diterpenes possessing a 2,3,4-oxidized briarane skeleton have been isolated from a gorgonacean Briareum sp.
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■ Ozonolysis of Tri- and Tetra-substituted Furans to α-Dicarbonyl Compounds
Nobuhiro Sato,* Masanori Kondo, and Edward C. Taylor
*Department of Chemistry, Yokohama City University, Yokohama 236, Japan
Abstract
This paper reports the oxidative conversion of 2,4,5-trimethylfur-3-yl and 2,4-dimethylfur-3-yl groups with ozone into pyruvoyl substituents.
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■ Asymmetric Synthesis of 3-Quinolylalkylamine by Enantioselective Alkylation of N-Diphenylphosphinyl-3-quinolylimine Using Chiral β-Amino Alcohols
Tadakatsu Hayase, Shunji Osanai, Takanori Shibata, and Kenso Soai*
*Department of Applied Chemistry, Faculty of Science, Science University of Tokyo, Kagurazaka 1-3, Shinjuku-ku, Tokyo 162-8601, Japan
Abstract
Chiral N-diphenylphosphinyl-3-quinolylamies (DPP amines) with up to 74.9% e.e. were obtained by the enantioselective alkylation using dialkylzincs in the presence of various chiral amino alcohols. The acidic hydrolysis of the chiral DPP amine afforded optically active chiral 3-quinolylamine without racemization.
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■ Synthesis of Some New Spiro[indoline-3,2'-(1',2',3',4'-tetrahydroquinoline)]-2,4'-dione Derivatives
Marzoog S. Al-Thebeiti
*Department of Chemistry, Faculty of Applied Sciences, Umm Al-Qura University, Makkah Almukkarramah, P. O. Box 6876, Saudi Arabia
Abstract
Indole-2,3-dione (1) was treated with malonic acid in a mixture of ethanol/pyridine to afford 3-(2-oxoindolinylidine)acetic acid (2), which then reacted with hydrobromic acid to yield 3-bromo-3-(2-oxoindol)acetic acid (3). Compound (3) reacted with aromatic amines to yield 3-arylamino-3-(2-oxoindole)acetic acid derivatives (4a-e). Cyclization of compounds (4a-e) with triflic acid afforded spiro[indoline-3’,2’-(1’,2’,3’,4’-tetrahydroquinoline)]-2,4’-dione derivatives (6a-e). Alkylation of compounds (4a-e) with methyl iodide gave 3-arylmethylamino-2-(1-methyl-2-oxoindole)acetic acid derivatives (5a-e). Cyclization of compounds (5a-e) with triflic acid yielded spiro[indoline-3,2’-(1’,2’,3’,4’-tetrahydroquinoline)]-1,1’-dimethyl-2,4’-dione derivatives (7a-e). Also alkylation of compounds (6a-e) with methyl iodide yielded compounds (7a-e).
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■ Synthesis of a New δ-Lactone Bridged Apovincamine Derivative
Gábor Nárai, Pál Sohár, Antal Csámpai, and Béla Zsadon*
*Institute of Chemistry, Eötvös Loránd University Budapest, H-1518 Budapest 112, P.O.Box 32, Hungary
Abstract
Starting from (+)-17,18-dehydroapovincamine, a new δ-lactone bridged apovincamine derivative (6) was synthesized in two steps involving oxidative hydroboration followed by catalytic hydrogenation. The structure elucidation of this compund, the intermediate and the by-products was performed by IR, 1H- and 13C-NMR methods including DNOE measurements.
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■ New [1,2] Rearrangement of p-Toluenesulfonyl Group in Azoles by n-Butyllithium
Dong Ju Jeon, Dong Wook Yu, Hyoung Rae Kim, and Eung K. Ryu*
*Korea Research Institute of Chemical Technology, P.O. Box 107, Yusong Daejeon 305-606, Korea
Abstract
A new type of [1,2] rearrangements of toluenesulfonyl group from nitrogen to neighboring carbon atom by n-butyllithium in tetrahydrofuran has been achieved in azoles, where the addition of lithium bromide accelerated the reaction in good yields.
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■ Cycloaddition Reactions of Azidomethyl Phosphonate with Acetylenes and Enamines. Synthesis of Triazoles
Frédéric Louërat, Khalid Bougrin, André Loupy,*Ana Ma Ochoa de Retana, Jaione Pagalday, and Francisco Palacios*
*Departamento de Química Orgánica, Facultad de Farmacia, Universidad del País Vasco, Apartado 450, 01080 Vitoria-Gasteiz, Spain
Abstract
β-Functionalized alkyltriazoles can be efficiently prepared under solvent-free conditions, eventually by coupling with microwave activation. Cycloadditions of azides and poorly activated acetylenes or enamines are thus possible with interesting selectively in the latter case.
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■ One-Pot Access to 2,3-Disubstituted 1,2,3,4-Tetrahydroquinolines by Reductive Amination of Aldehydes with Sodium Cyanoborohydride
Guy Lewin* and Corinne Schaeffer
*Laboratoire de Pharmacognosie, Faculte de Pharmacie, boulevard Becquerel, 14032 Caen, France
Abstract
Slight modification of the reductive amination Borch method (delayed addition of NaBH3CN) provided an easy one-pot synthesis of 1,2,3,4-tetrahydroquinoline derivatives from enolizable aldehydes.
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■ Saturated Heterocycles, Part 257. Preparation and Structure of Partially Saturated Isoindolo[1,2-b]- and -[2,1-a]quinazolinones
Pál Sohár, Géza Stájer, Angela E. Szabó, József Szúnyog, and Gábor Bernáth*
*Institute of Pharmaceutical Chemistry, Albert Szent-Györgyi Medical University, POB 121, H-6701 Szeged, Eötvös u. 6, Hungary
Abstract
Through the reactions of 2-carboxybenzaldehyde (1) with cis- or trans-2-amino-1-cyclohexylmethylamine (2a,b) or cis- or trans-2-amino-4-cyclohexenyl-1-methylamine (2c,d), the partially saturated isomeric isoindolo[1,2-b]- (3, 4, 6-8) and -[2,1-a]quinazolinones (5) were obtained. After separation, the structures of products (3-8) were established by NMR methods, including 2D-HSC DNOE and DEPT measurements. From the cis 2a, two linearly C/D cis-fused and one angularly C/D trans-fused tetracycles were formed.
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■ Synthesis of New 2-Highly Branched 5-Nitroimidazoles by Bis-SRN1 Methodology
Patrice Vanelle,* Kamel Benakli, José Maldonado, and Michel P. Crozet
*Laboratoire de Chimie Organique, Université de la Méditerranée, Faculté de Pharmacie, 27, Boulevard Jean Moulin, 13385 Marseille Cedex 05, France
Abstract
A versatile bis-SRN1 methodology allows straightforward access to 2-highly branched 5-nitroimidazoles by reacting 3-chloro-2-chloromethyl-1-(1-methyl-5-nitroimidazol-2-yl)prop-1-ene with various nitronate anions.