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. 43, No. 10, 1996
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■ Reactions of Methacryloyl Isocyanate with Imines Derived from Ketones and Alkyl Amines
Otohiko Tsuge, Taizo Hatta, Masaaki Kuwata, Tadahiro Yamashita, and Akikazu Kakehi
*Department of Industrial Chemistry, Kumamoto Institute of Technology, 4-22-1, Ikeda, Kumamoto
Abstract
The reactions of methacryloyl isocyanate (MAI) with imines derived from ketones and alkyl amines led to the formations of the corresponding 2H-1,3,5-oxadiazin-4(3H)-one, 1,3-oxazine, piperidinedione, and/or 1-alkyl-1-alkenyl-3-methacryloyures, whose relative yields greatly depended on the reaction conditions as well as the nature of imine. The latter three compounds sorrespond to products arising from the reaction of MAI with enamine tautomers of imines.
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■ Reaction of 1,2,4-Triazine 1-Oxides with Benzyne: Formation of 1,3-Benzoxazepine and 1,3,5,6-Benzoxatriazonine Derivatives
Naoki Kakusawa, Kazunori Sakamoto, Jyoji Kurita, and Takashi Tsuchiya
*School of Pharmacy, Hokuriku University, 3-Ho, Kanagawa machi, Kanazawa 920-1181, Japan
Abstract
Reaction of the 6-unsubstituted 1,2,4-triazine 1-oxides (5) with benzyne gave the 1,3-benzoxazepines (8) and/or the 6-(o-hydroxyphenyl)-1,2,4-triazines (10) via the unisolable 1,3-dipolar cycloadducts (6), whereas the 6-substituted compound (12), 5,6-dimethyl-3-methoxy-1,2,4-triazine 1-oxide, afforded only the relativily stable 1,5-shift product (15) derived from the initially formed 1,3-dipolar cycloadduct (13). Heating the adduct (15) gave the novel 1,3,5,6-benzoxatriazonine derivative (16) and 2,3-dimethylbenzofuran (17).
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■ Ring Transformation of 3-Halo-1,2,4-triazines with α-Chlorocarbanions: A Novel Route to Pyrazoles with Sulfonyl, Sulfonamido and Sulfonyloxy Groups
Andrzej Rykowski and Danuta Branowska
*Institute of Chemistry, Agricultural University at Siedlce, 08-110 Siedlce, ul. 3-go Maja 54, Poland
Abstract
A novel route to pyrazoles bearing sulfonyl, sulfonamido and sulfonyloxy groups at C-3 by ring cleavage reaction of 3-halo-6-phenyl-1,2,4-triazines (1a-b) with α-halocarbanions (2a-g) is described.
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■ A Convenient Access to Protoberberine Derivatives
Imanol Tellitu, Dolores Badía, Esther Domínguez, and Luisa Carrillo
*Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Pais, Vasco, P.O. Box 644, 48080-Bilbao, Basque Country, Spain
Abstract
A synthesis of protoberberine derivatives starting from (1R*,3S*,4R*)-3-aryl-1-methyl-4-silyloxytetrahydroisoquinolines is presented. The influence of the substitution pattern of the aryl ring at C-3 and the effect of the derivatization of the hydroxyl group at C-4 on the final cyclization reaction is discussed.
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■ Total Synthesis of Amphimedine
Shinsuke Nakahara, Yoshihiro Tanaka, and Akinori Kubo
*Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan
Abstract
The cytotoxic fused pentacyclic aromatic alkaloid, amphimedine (2) from a Pacific sponge, was synthesized employing hetero Diels-Alder reacions.
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■ Stereochemistry of the Products of Base Catalyzed Self-Condensation of Biacetyl
John Hudec, Trevor A. Crabb, and Asmita V. Patel
*Department of Chemistry, University of Potsmouth, Nuffield Centre, St. Michael's Road Portsmouth PO1 2DT, U.K.
Abstract
The structures of the base catalyzed trimer and dimer of biacetyl have been deterimined.
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■ Synthesis of 2- or/and 6-Methylated Analogues of Isoguvacine (1,2,3,6-Tetrahydropyridine-4-carboxylic Acid) a GABAA Agonist
Markus Rohr, Saïd Chayer, Fabrice Garrido, André Mann, Maurizio Taddei, and Camille-Georges Wermuth
*Laboratoire de Pharmacochimie Moleculaire, (UPR 421 DU CNRS), Centre de Neurochimie du CNRS, 5, rue Blaise Pascal, 67084 Strasbourg-Cedex, France
Abstract
1,2,3,6-tetrahydropyridine-4-carboxylic acid (isoguvacine) and related 2-and/or 6-methylated analogues (1-4) were synthesized using the methoxycarbonylation [Pd(OAc)2, PPh3, CO, MeOH)] of their corresponding vinylic triflates. Analogue (5), the 6-methyl-1,2,3,6-tetrahydropyridine-4-carboxylic acid was obtained after a reductive deoxygenation of the corresponding β-keto ester.
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■ Studies on Nitrogen-containing Heterocyclic Compounds. Novel Synthesis of Naphtho[1,2-b and 2,1-b][1,8]naphthyridines and Oxidation Reactions with Peroxy Acids
Isao Takeuchi, Koosuke Asai, Yoshiki Hamada, Katsuyoshi Masuda, Hiroko Suezawa, Minoru Hirota, Yukihisa Kurono, and Keiichiro Hatano
*Faculty of Pharmacy, Meijo University, 150 Yagoto, Tempaku-ku, Nagoya, Aichi 468-8503, Japan
Abstract
A modified Friedländer condensation of 2-aminonicotinaldehyde with α- and β-naphthols lead successfully to two new naphtho[1,2-b and 2,1-b][1,8]naphthyridines in a single synthetic procedure. The oxidation of the naphthonaphthyridines with peroxy acids afforded novel products such as a seven-membered oxazepine moiety. Structures were characterized by standard spectroscopy. The crystal and molecular structures (3) and (4) were determined by X-ray analyses.
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■ Novel Barbituric Acid Derivatives, Uracil-pyridinium Salts and Polycondensed Oxopyrimidines
Andreas Schmidt, Annemarie Hetzheim, and Dirk Albrecht
*Institut für Chemie und Biochemie, Ernst-Moritz-Arndt-Universität Greifswald, Soldmannstrasse 16, D-17487 Greifswald, Germany
Abstract
Nucleophilic substitution of the 6-chloropyrimidines (1) with piperodine, morpholine, 4-(piperidin-1-yl)piperidine and 4-dimethylaminopyridine yielded the corresponding 6-aminosubstituted pyrimidines (2), (3), (4), and (5), respectively. The barbiturates (9) and (10) were formed either starting from the chloroaldehyde (7), or by applying Knovenagel reaction to the barbituric acid (13) with 2-formylaminohetarenes. Cyclocondensation of the chloroldehyde (11) with 2-aminnopyrisines resulted in the formation of the tricycle (12) which is also sccessible by initial Knoevenagel reaction of the barbituric acid (14) and subsequent cyclization of the resulting barbiturates (15). Analogously, the new ring system (17) was formed upon treatment of 14 with 2-formylaminopyrimidine and subsequent cyclization.
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■ Synthesis and Photobiological Activity of N-Substituted 2-Oxo-2H-1-benzopyran-3-(thio)carboxamides
Youssef El-Ahmad, Jean-Daniel Brion, Pierre Reynaud, Dietrich Averbeck, and Simone Averbeck
*Laboratoire de Chme Thérapeutique, Faculté de Pharmacie, 5, Rue, Av. J.B. Clément, 92296 Chåtenay-Malabry Cedex, France
Abstract
Several polyfunctional coumarins and the corresponding uatenary ammoniums, associated with a coplanar structure have been synthesized in order to test the relationships between structure and photobiological activity. In vitro studies on their phototoxic effects in yeasts suggest that five of them are able to intercalate in DNA and to covalently photobind tto DNA.
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■ 1,3-Cycloaddition of Benzonitrile Oxides to Diazepines. III. 1H-1,2-Benzodiazepine
Paolo Beltrame, Enzo Cadoni, Maria M. Carnasciali, Gioanna Gelli, and Angelo Mugnoli
*Dipartimento di Scienze Chimiche, Universita di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042, Nonserrato(CA), Italy
Abstract
Arylnitrile oxide (1) and 1H-1,2-benzodiazepine(2) undergo 1,3-cycloaddition reactions to give derivatives of 1,2,4-oxadiazole (3) and isoxazole (4). Aithough usually stable, the nitrile oxide partly dimerizes giving a 1,2,4-oxadiazole (7). Secondary products were also identified: for one of the (6) the structure was unambiguously determined by X-ray diffraction. Overall kinetics and product distribution were measured at 40-70°C, in mixtures of 1,1,2,2-tetrachloroethane and DMF: a set of parallel reactions was evidenced.
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■ First Example of a 4-Amino-1,2,4,6-thiatriazine 1,1-Dioxide Derivative
Carmen Ochoa, Angela Herrero, Rafael Provencio, Jan Balzarini, Erik De Clercq, Alicia Gómez-Barrio, Rafael Martinez Díaz, and Juan José Nogal
*Instituto de Química Médica, C. S. I. C., Calle Juan de Cierva, 3, 28006 Madrid, Spain
Abstract
For teh first time, an N4-amino derivative of 1,2,4,6-thiatriazine 1,1-dioide (5) was prepared by cyclocondensation reaction of the appropriate sulfamoylcarbamate (3) with hydrazine. Reaction of 3 with ammonia yielded the cyclic 4H-derivative (4). Nucleophilic substitution reactions of 4 and 5 with hydrazine, as well as comdensation of 5 with ethyl orthoformate were achieved. The antiprotozoal and anti-HIV properties of the new compounds were evaliated, but none of them showed significant biological activities.
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■ Tin(IV) Chloride Catalyzed Herero-Diels-Alder Reaction of Methyl 2-Oxo-4-phenyl-3-butenoate with Styrene
Akira Sera, Naohiro Ueda, Kuniaki Itoh, and Hiroaki Yamada
*Department of Chemistry, Faculty of Science, Kobe University, Nada-Ku, Kobe 6557-8501, Japan
Abstract
Hetero-Diels-Alder reactions of methyl 2-oxo-4-phenyl-3-butenoate with stryene to give dihydropyran derivatives were found to proceed through an exo-selective concerted as well as an ionic stepwise mechanisms concurrently.
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■ Oxidative Free Radical Reaction of 2-Phenylthio-1,4-naphthoquinones Initiated by Manganese(III) Acetate
Che-Ping Chuang and Sheow-Fong Wang
*Department of Chemistry, Natioanl Cheng Kung University, Tainan, 70101, Taiwan, R.O.C.
Abstract
A free radical reaction between 2-phenylthio-1,4-naphothoquinines and diethyl malonate initicated by manganese(III) acetate is described. This free tadical reaction provides a new method for the synthesis of 6,11-dihydro-6,11-dioxo-12H-5-thianaphthacenes. This reaction was performed in various solvents, the best results were obtained in DMSO. With meta substituent on phenylthio ring, this reaction shows unusual high regioselectivity.
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■ Biogenetic Synthesis of Biflavonoids, Lophirones B and C, from Lophira lanceolata
Tomoyuki Shimamura, Yuka Arakawa, Kiyomi Hikita, and Masatake Niwa
*Faculty of Pharmacy, Meijo University, 150 Yagoto, Tempaku-ku, Nagoya, Aichi 468-8503, Japan
Abstract
A biogenetic synthesis of biflavonoids, lophirone A and Lophirone C, was achieved by enzymatic oxidation of the corresponding chalcone.
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■ Total Synthesis of (8'R)- and (8'S)-Corossoline
Hidefumi Makabe, Hisahide Tanimoto, Akira Tanaka, and Takayuki Oritani
*Division of Environmental Bioremediation, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiya, Aoba-ku, Sendai 981-8555, Japan
Abstract
A convergent stereoselective total synthesis of (8’R)- and (8’S)-corossoline (1) has been performed via a multi-step process. Comparison of the mp, [α]D, ir and nmr data of both synthetic materials with those reported for natural corossoline did not allow for the strict deterimination of the donfiguration at the C-8’ hydroxyl group of 1. However, a slight chemical shift difference at the C-8’ methine proton was observrd in the 1H-nmr spectra of the corresponding tris-MTPA esters of synthetic (8’R)- and (8’S)-1, indicating that if the tris-MTPA ester of natural 1 is available, the stereochemistry at the C-8’ hydroxyl group of corossoline will be established.
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■ Synthesis of 1-Isopropylamino-3-(pyrazolo[1,5-a]pyridyloxy)-2-propanols
Yasuyoshi Miki, Junko Tasaka, Kyoko Uemura, Kunihiro Miyazeki, and Jun Yamada
*Faculty of Pharmaceutical Sciences, Kinki University, 3-4-1, Kowakae, Higashi-Osaka 577-8502, Japan
Abstract
Treatment of the 4-hydroxypyrazolo[1,5-a]pyridine with glycidyl tosylate in the presence of base, followed by reaction with isopropylamine gave 1-isopropylamino-3-(pyrazolo[1,5-a]pyrid-4-yloxy)-2-propanol. In a similar manner, 1-isopropylamino-3-(pyrazolo[1,5-a]pyrid-6- and 1-isopropylamino-3-(pyrazolo[1,5-a]pyrid-3-yloxy)-2-propanol were also prepared.