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. 41, No. 7, 1995
Published online:
■ Dimerization of Norisoacronycine
Shinji Funayama, Tomoko Aoyagi, Kaori Tadauchi, Tzu-Yun Pan, Shigeo Nozoe*, and Geoffrey A. Cordell
*Department of Pharmacognosy, Faculty of Pharmaceutical Sciences, Tohoku University, Aobayama, Sendai 980, Japan
Abstract
A new type of acridone dimer with a C-C junction between the prenyl moieties was obtained by treating norisoacronycine under acidic conditions. The chemical structure was deduced mainly by the comparison of its nmr spectral data with those of the acridone dimers which had been prepared previously.
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■ A Concise Approach to Antifertility Agents; Structural Analogues of Yuehchukene
Minoru Ishikura*
*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-02, Japan
Abstract
Palladium catalyzed carbonylative cross-coupling reaction using lithium triethyl(1-methylindol-2-yl)borate (1) was applied in a concise formation of structural analogues of yuehchukene.
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■ Synthesis and Antibacterial Activity of 1-Cyclopropyl-6,8-difluoro-7-(2-substituted 4,6-dihydro-1H-pyrrolo[3,4-d]thiazol-5-yl)-1,4-dihydro-4-oxoquinoline-3-carboxylic Acid
Wan-Joo Kim*, Bong-Jin Kim, Tae-Suk Lee, Keun-Soo Nam, and Keun-Jae Kim**
*Korea Research Institute of Chemical Technology, Pharmaceutical Division, P.O. box 107, Yu-Sung ku, Taejon, Korea 305-606
Abstract
Quinolone derivatives (9 and 10) substituted with bicyclothiazole (7) and (8) at C-7 position were synthesized. Bicyclothiazole derivatives (7 and 8) were prepared through 9 steps by way of the 4-bromo-3-oxopyrrolidine (16) was a key intermediate and introduced into the title compounds as new C-7 substituents. In vitro antibacterial activity of 9 and 10 was also reported.
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■ Simultaneous Conversion of N(1)-(2-Aminoethyl)adenosine to N6-(2-Aminoethyl)adenosine and Tricyclic 1. N6-Ethanoadenosine under Mild Aqueous Conditions
Andreas F. Bückmann,* Victor Wray, and Henk C. van der Plas
*Department of Enzymology, GBF, Gesellschaft für Biotechnologische Forschung mbH, Mascheroder Weg 1, D-38124 Braunschweig, Germany
Abstract
Under mild aqueous conditions (50 °C, pH range 6 - 7) N(1)-(2AE)-adenosine (2) can be converted to N6-(2AE)-adenosine (7) by Dimroth rearrangement at unexpectedly high rate. In a parallel reaction tricyclic 1,N6-ethanoadenosine (6) is formed. The latter reaction is new in heterocyclic organic chemistry and is strongly catalysed by the monoanions of phosphoric and arsenic acid and, less strongly, by the acetate anion.
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■ Design and Synthesis of Imidazolium Cyclophane
Meiming Luo, Shengjin Guo, Chenghe Zhou, and Rugang Xie*
*Department of Chemistry, Sichuan University, Chengdu 610064, P. R. China
Abstract
1,4-Diimidazol-1-ylbutane (2) was prepared by PTC technique. Treatment of 2 with α,α’-dibromoxylene afforded novel imidazolium cyclophanes (3a,b) in good yields.
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■ Alkaloids from the Neutral Fraction of Telitoxicum krukovii
Mary D. Menachery*, Geoffrey W. Blake, Cathleen Beiswenger, and Alan Freyer
*Penn State Altoona, 3000 Ivyside Park, Altoona, Pennsylvania 16601-3760, U.S.A.
Abstract
Two new aporphinoids N-formyldehydroanonaine (1), telikovinone (2), and the known alkaloids N-demethyl-N-formyldehydronuciferine, N-formylnuciferine, 7-chloro-6-demethylcepharadione B, and norcepharadione B have been isolated and identified from the neutral fraction of Telitoxicum krukovii.
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■ Reaction of Pentafluoropyridine and α-Lithiated Arylacetonitriles with n-Butyllithium and Methyllithium in Ether
Edward R. Biehl,* Hala Mohammed Refat, and Amamed A. Fadda
*Department of Chemistry, Southern Methodist University, Dallas, TX 75275, U.S.A.
Abstract
Treatment of one equivalent each of pentafluoropyridine (6) and n-butyllithium with two equivalents of lithioarylacetonitriles (3) gave α-aryl-4-n-butyl-3,5,6-trifluoro-2-pyridylacetonitrile (9) in good yields (83-85%). Similar treatment of equivalent amounts of 6, 3, and methyllithium gave α-aryl-2,3,5,6-tetrafluoro-4-pyridylacetonitriles (11) also in good yields (79-87%). The introduction of the n-butyl and α-arylacetonitrile groups most likely arise through nucleophilic aromatic substitution pathways.
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■ An Efficient Asymmetric Aldol Reaction of 4-Trimethylsiloxy-6-methylene-1,3-dioxines by Chiral Binaphthol-Titanium Complex Catalysis
Masayuki Sato,* Satoshi Sunami, Yoshiaki Sugita, and Chikara Kaneko
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, Japan
Abstract
The asymmetric aldol reaction of 4-trimethylsiloxy-6-methylene-1,3-dioxines or the 6-ethylidene analogue with achiral aldehydes proceeds in a highly enantioselective manner under chiral binaphthol-titanium complex catalysis to afford 6-substituted 1,3-dioxin-4-ones which serve as chemical equivalents of δ-hydroxy-β-keto esters, potential chiral building blocks. An explanation for the stereoselectivity is also presented.
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■ [4+2]Cycloaddition Reactions of 1,4-Bis(trifluoromethyl)pyrido[3,4-d]pyridazine with Indole-Type Dienophiles
Norbert Haider,* Kurt Mereiter, and Richard Wanko
*Institute of Pharmaceutical Chemistry, University of Vienna, Althanstrasse14, A-1090 Vienna, Austria
Abstract
[4+2] Cycloaddition reactions of the title compound (1) with electron-rich indole-type dienophiles afford — besides different types of side products — tetracyclic compounds with a pyridocarbazole skeleton, structurally related to the alkaloid ellipticine or its isomer, isoellipticine. Three of the reaction products (compounds 4, 5, and 10) were characterized by X-ray structure determination.
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■ Pyridazines, 74. Synthesis of Novel 4,5-Disubstituted Pyridazines by Homolytic Substitution and Structure Determination of Unexpected Reaction Products
Gottfried Heinisch,* Barbara Matuszczak, Kurt Mereiter, and Josef Soder
*Institute of Pharmaceutical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria
Abstract
Synthesis of the 5-aryloxymethyl-4-pyridazinecarboxylic acid derivatives (1a-d) and of the analogous thioethers (1e,f) by radical reactions in a two-phase system is reported. The stereochemical assignment of unexpected dimeric reaction products formed in the absence of an organic layer is presented.
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■ A Versatile Synthesis of Substituted Indazoles
Jin Il Kim, Byung Chul Kim, Seung Wook Moon, and Yurngdong Jahng*
*College of Pharmacy, Yeungnam University, Kyongsan 712-749, Korea
Abstract
A four-step synthetic sequence for substituted indazoles was presented from 2-acylcyclohexane-1,3-diones via either simultaneous or stepwise dehydration and dehydrogenation of 4-substituted 4-hydroxy-4,5,6,7-tetrahydroindazoles as a key step.
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■ Reactivity of N1-Acylacetamidrazones towards Diethyl Acetylenedicarboxylate: Cyclization to Ethyl Pyrroleacetates and 1-Acylaminopyridones
Angela Maria Bernard, Maria Teresa Cocco,* Cenzo Congiu, Valentina Onnis, and Pier Paolo Piras
*Dipartimento Farmaco Chimico Tecnologico, Via Ospedale n° 72, I-09124 Cagliari, Italy
Abstract
The reaction between N1-acylacetamidrazones (1) and diethyl acetylenedicarboxylate (2) is described. The nucleophilic addition of the β-carbon atom of 1 on the triple bond affords the non isolable intermediate (3). Depending on the reaction conditions and on the substitution pattern of the amidrazone, 3 gives rise to ethyl 5-(2-acylhydrazino)-4-(ethoxycarbonyl)-2-oxo-2H-pyrrole-3-acetates (4) and / or diethyl 1-acylamino-2-amino-1,6-dihydro-6-oxo-3,4-pyridinedicarboxylates (5).
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■ Heterocyclic Amidines: I. A One-Step Synthesis of New α-Substituted Imidazolylphenylacetic Acids
Carmela Saturnino, Mustapha Abarghaz, Martine Schmitt, Camille-Georges Wermuth, and Jean-Jacques Bourguignon*
*Laboratoire de Pharmacochimie Moléculaire, UPR 421 du CNRS, Centre de Neurochimie, 5 rue Blaise Pascal 67084 Strasbourg Cedex, France
Abstract
The reaction of α-phenyl-β-formylacrylic derivatives with various amidines (benzamidine, acetamidine) and heterocyclic amidines (2-aminopyridines, 3-aminopyridazines), yields α-substituted imidazolylphenylacetic acids and imidazo[1,2-x]azines bearing a phenylacetic acid residue in position 3. Some mechanistic aspects of the cyclocondensation reaction will be discussed.
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■ Optimization of Synthesis of Nitroimidazoles and Nitropyrazoles Based on Polarographic Investigations
Dragica Dumanovic*, Djuro Kosanovic, and Petr Zuman
*ICN Galenika Institute, 29., novembar 111, 11000 Belgrade, Yugoslavia
Abstract
Direct, simple, fast and inexpensive polarographic method enables selective determinations of nitroimidazoles or nitropyrazoles (nitroazoles) in mixtures which can be used for monitoring synthetic processes and selecting optimal conditions for synthesis.
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■ Synthesis and Reactions of Lithiated Monocyclic Azoles Containing Two or More Hetero-atoms. Part VI: Triazoles, Tetrazoles, Oxadiazoles, and Thiadiazoles
M. Ross Grimmett and Brian Iddon*
*The Ramage Laboratories, Department of Chemistry and Applied Chemistry, University of Salford, Salford M5 4WT, England
Abstract
The metallation and halogen → metal exchange reactions of 1,2,3- and 1,2,4-triazoles, tetrazoles, 1,2,3-, 1,2,4-, 1,2,5-, and 1,3,4-oxadiazoles, and 1,2,3-, 1,2,4-, 1,2,5-, and 1,3,4-thiadiazoles and the reactions of the resulting organometallic derivatives, particularly lithiated derivatives, are reviewed comprehensively.