HETEROCYCLES
An International Journal for Reviews and Communications in Heterocyclic ChemistryWeb Edition ISSN: 1881-0942
Published online by The Japan Institute of Heterocyclic Chemistry
Special Issue
Alan R. Katritzky's Special Issues, Vol. 37, No. 1, 1994
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■ Cyclization with Nitrenium Ions Generated from N-Methoxy- or N-Allyloxy-N-chloroamides with Anhydrous Zinc Acetate. Synthesys of N-Hydroxy- and N-Methoxynitrogen Heterocyclic Compounds
Yasuo Kikugawa,* Masahiro Shimada, and Kazuhiro Matsumoto
*Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japana
Abstract
Electrophilic intramolecular aromatic substitution with an N-methoxy- or an N-allyloxyacylnitrenium ion, generated by treatment of an N-methoxy- or an N-allyloxy-N-chloroamide with anhydrous zinc acetate in nitromethane, leads to formation of a nitrogen heterocyclic compound bearing an N-methoxy- or N-allyloxy group. The latter is readily converted to the corresponding N-hydroxy compound by palladium-catalyzed removal of the allyl group.
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■ Studies on the Site-selective N-Acyliminium Ion Cyclization: Synthesis of (±)-Glochidine and (±)-Glochidecine
Yong Sup Lee, Sung Hwan Kim, Sun Ho Jung, Sook Ja Lee, and Ho-Koon Park*
*Organic Chemistry Laboratory, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, Korea
Abstract
Studies on the N-acyliminium ion cyclization of hydroxylactams bearing both carbon and nitrogen nucleophile in the same molecule are described. The site selection in the cyclization of hydroxylactam could be controlled by the absence or presence of acid catalyst to afford (±)-glochidine and (±)-glochidicine.
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■ 1-Alkoxymethyl- and 1-Alkylthiomethyl-4-dimethylaminopyridinium Chlorides
Pernak Juliusz* and Michalak Lucyna
*Poznan Technical University, Institute of Chemical Technology and Engineering, pl.Sklodowskiej-Curie 2, 60-965 Poznan, Poland
Abstract
ROCH2Cl or RSCH2Cl reacts with DMAP to form stable pyridinium chlorides. Reaction of these chlorides with NaOH produces the corresponding 4-pyridones. N-Alkoxymethylation of a free NH group of azoles is developed from 1-alkoxymethyl-4-dimethylaminopyridinium intermediates.
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■ Synthesis of Some Novel Naphthoquinone Fused Selenazoles and 2-Amino-3-alkylseleno-1,4-naphthoquinones
Ming-De Ruan,* Zheng-Jie Wu, Wei-Qiang Fan,* Xun-Jun Zhou, and Rong-Shen Ma
*Department of Chemistry, Hangzhou University, Zhejiang, China 310028, China
Abstract
A variety of 2-aryl-4,9-dioxonaphtho[2,3-d]selenazoles (4) are prepared from reactions of appropriate aromatic aldehydes and 2-amino-3-seleno-1,4-naphthoquinone sodium salt (3), which is prepared from 2-amino-3-chloronaphthoquinone (2), sodium and selenium powder without isolation. The intermediate (3) reacts with a range of alkyl halides to give 2-amino-3-alkylseleno-1,4-naphthoquinones (5).
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■ On the Bromination of the Three Isomeric Thieo[c]fused 1,5-Naphthyridines and Their 5-N-Oxides
Johan Malm, Anna-Britta Hörnfeldt, and Salo Gronowitz*
*Organic Chemistry 1 Chemical Center, University of Lund, P. O. Box 124, S-221 00, Lund, Sweden
Abstract
Thieno[3,4-c]-1,5-naphthyridine (1) and its 5-N-oxide (5) were conveniently brominated at room temperature with tetrabutylammonium perbromide in the presence of a large excess of sodium hydrogen carbonate. Compound (1) gave the 1- and 3-bromo derivatives in a 4:1 ratio, while 5 was regioselectively brominated in the 3-position. Thieno[2,3-c]-1,5-naphthyridine (7), its 5-N-oxide (11) and thieno[3,2-c]-1,5-naphthyridine (14) did not react under these conditions, but gave products in the reaction with bromine in refluxing thionyl chloride. Compound (7) gave the 1-brow derivative as main product and interestingly the 1,7-dibromo derivative as by-product. The reaction of 11 and 14 with bromine in thionyl chloride gave mainly chlorinated products.
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■ Synthesis and Conformation of 3-Nitro-2-[1-(L)-prolyl]thiophene Derivatives
Kondam Venodhar Reddy and Srinivasachari Rajappa*
*Division of Organic Chemistry (Synthesis), National Chemical Laboratory, Pune 411 008, India
Abstract
Chiral thiophene derivatives with a strong push - pull system (nitroenamine) have been synthesized and their solution conformation has been determined.
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■ Studies towards 3,4-Dimethoxy-1-methyl-1,2-dihydropyridine, So-called Arecolidine, or Its Tautomers
Eckehard V. Dehmlow* and Ralf Westerheide
*Fakultät für Chemie, Universität Bielefeld, D33615 Bielefeld, Germany
Abstract
Different synthetic paths towards the title compound (2) lead to intermediates (3, 11, 13, 14, 15, and 17). All of these, but especially 3 and 14 are very close to the target molecule or its tautomers. These, however, turn out to be too unstable for isolation. Thus, the structure of the compound described as arecolidine must be wrong.
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■ Electron Impact Mass Spectra of para-Substituted N-Heteroaryl Benzylamines
Rossella Fioravanti,* Mariangela Biava, Giulio Cesare Porretta, Salvatore Foti, Giuseppe Musumarra,* and Rosaria Saletti
*Dipartimento di Studi e Tecnologia delle Sostanze Biologicamente Attive, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, 00185 Roma, Italy
Abstract
The 70 eV electron impact mass spectra of some para-substituted N-heteroaryl benzylamines, synthesized through the corresponding Schiff bases, are reported. Typical fragmentation patterns are discussed with the aid of mass analyzed ion kinetic energy spectra and exact mass measurements. The compounds are relatively stable under electron impact, the molecular ion being the base peak or the second most intense ion in the spectra. The dominating breakdown process is the benzylic cleavage, that gives rise to the base peak in some of the investigated compounds and to the second intense peak in others.
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■ Aminations with Oxaziridines – Synthesis of Aryl- and Hetarylhydrazines
Siegfried Andreae* and Ernst Schmitz
*Zentrum für Selektive Organisch Synthese, KAI e V., Rudower Chaussee 5, D-12489, Berlin-Adlershof, Germany
Abstract
Five acetylaminobenzenes (2) (X=CH), two 3-acetylaminopyridines (2) (X=N) and one 3-acetylaminopyridine-1-oxide (2) (X=N(O)) are aminated by 1-oxa-2-azaspiro[2.5]octane (1) / DABCO to cyclohexylidenehydrazino compounds (3), which are characterized as benzaldehyde or 4-nitrobenzaldehydehydrazones (4). In some cases the acetyl group is removed during the amination.
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■ Synthesis of Hybrid Tilivallines and Their 11-Cyano Analogs
Nobuyuki Matsunaga, Toyohiko Aoyama, and Takayuki Shioiri*
*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
Abstract
Hybrid tilivallines (4), derived from tilivalline (1a) and anthramycin (2) or tomaymycin (3), and their 11-cyano analogs (15) have been efficiently synthesized from the acetal amides (7a, b) : the key step is an intramolecular Mannich type cyclization accompanied with introduction of indole or nitrile function.
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■ Synthesis of 3,4-Dihydropyridazino[1,6-a]benzimidazoles
Mohamed Khodja, Dieter Sicker, and Horst Wilde*
*Institut für Organische Chemie, Universität Leipzig, Johannisallee 29, D-04103 Leipzig, Germany
Abstract
3,4-Dihydropyridazino[1,6-a]benzimidazoles (4a-e) have been prepared by catalytical hydrogenation of dialkyl (E)-2-(substituted 2-nitrophenylhydrazono) glutarates (1a-e) to the respective amines (2) followed by their base catalyzed cyclization in a tandem reaction proceeding via 4,5-dihydropyridazin-6(1H)-one intermediates (3).
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■ Preparation of Optically Active Tricyclic 1,4-Dioxepin-5-one Derivatives and Its Application to Asymmetric Alkylation
Keisuke Kato, Hiroshi Suemune, and Kiyoshi Sakai*
*Faculty of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
Abstract
Chiral hicyclic α,β-unsaturated lactones (6a,b and 8a,b) were easily synthesized from chiral cyclic diols (2-4) and cyclic β-keto esters (1a,b). Alkylation of 8b proceeded in a highly diastereoselective manner to afford a quaternary carbon.
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■ Lead Tetraacetate Oxidation of a Compound that is Simultaneously a 1- and a 2-Aminobenzotriazole
Dong Ok and Harold Hart*
*Department of Chemistry, Michigan State University, East Lansing MI 48824, U.S.A.
Abstract
Lead tetraacetate oxidation of bis-aminobiazole (8) in the presence of dienone (11) gave dinitrile (12) in good yield. Possible mechanisms are briefly discussed.
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■ Compounds with Bridgehead Nitrogen Part 74. NMR Spectra and Stereochemistry of 1,3,10,10a-Tetrahydro-5H-oxazolo[3,4-b]isoquinoline and 1,5,6,10b-Tetrahydro-3H-oxazolo[4,3-a]isoquinoline
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
Whereas 1,3,10,10a-tetrahydro-5H-oxazolo[3,4-b]isoquinoline adopts an equilibrium in CDCl3 solution at 295 K in which the trans-fused conformation predominates, 1,5,6,10b-tetrahydro-3H-oxazolo[4,3-a]isoquinoline adopts the O-inside cis-fused conformation. This difference in conformational preference has been explained partly in terms of ring-fusion strain.
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■ Generation of the Dihydro-5H-Thiazolo[3,2-a]pyridin-3-one Ring System by Proton Loss from Isothiomünchnones
Albert Padwa* and Zhijia J. Zhang
*Department of Chemistry, Emory University, 1515 Pierce Drive Atlanta, Georgia 30322, U.S.A.
Abstract
Dihydro-5H-thiazolo[3,2-a]pyridin-3-ones are easily generated by proton loss from isothiomÜnchnones. The closely related tetrahydro-2H-pyrido[2,1-b][1,3]thiazin-4-one ring system was prepared by heating piperidine-2-thione with acryloyl chloride. These cyclic S,N-ketene acetals undergo smooth reaction with different electrophiles in the presence of Lewis acids.
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■ Enantiomerically Pure β-Amino Sulfides amd β-Amino Thiols from Ephedrine
Martin A. Poelert, Robert P. Hof, Nathalie C. M. W. Peper, and Richard M. Kellogg*
*Department of Organic and Molecular, Inorganic Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherland
Abstract
Ephedrine and pseudoephedrine are converted by means of a Mitsunobu reaction to respectively trans- and cis-aziridines, which can be ringopened at the benzylic center with inversion of configuration by thiols and thiol acids. The trans-aziridine from ephedrine reacts also with H2S in acetone under which conditions the amino thiol is trapped as the thiazolane. The same aziridine also undergoes cycloaddition with CS2.
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■ Isomerism of Cephalosporin Esters; Theoretical and Practical Aspects
Emil Pop,* Marcus E. Brewster, Antonie Dinculescu, Ming-Ju Huang, and Nicholas Bodor
*Pharmos Corporation, 2 Innovation Drive, Alachua, FL 32615, U.S.A.
Abstract
Attempts to prepare 1,4-dihydropyridine targetor based chemical delivery systems (CDS) for 7-(thiophene-2-acetamido) cephalosporanic acid (cephalotin) (1) are reported. Reaction of 1 with hydroxyethylnicotinamide resulted in a mixture of δ2 and δ3 isomers of the 3-pyridinylcarbonylamino esters of 1; after chromatographic separation the δ3 isomer was N-methylated and the resulting quaternary pyridinium salt was reduced with sodium dithionite to give the CDS. Attempts to attach the dihydropyridine moiety to 1 as an acyloxyalkyl ester failed. Relative stabilities of the δ3 and δ2 isomers of cephalotin acid and methyl ester, as reflected by theoretically (AM1 and PM3) calculated heats of formation (δHf) indicated that kinetic and mechanistic, rather than thermodynamic factors are responsible for the isomerization of the esters.
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■ The Preparation of Thiophene Appended Vinylogous Iminium Salts and Their Application to the Regioselective Synthesis of Thienylpyrimidines and Thienylpyrroles
John T. Gupton,* Fred A. Hicks, Douglas R. Wilkinson, Scott A. Petrich, and James A. Sikorski
*Department of Chemistry, University of Central Florida, Orlando, Florida 32816, U.S.A.
Abstract
The synthesis of two, vinylogous iminium salts, which contain an appended thiophene group, are described along with their conversion to thiophene substituted pyrimidines and pyrroles.
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■ Synthesis of Pyrimidinyl Triflates and Palladium-catalyzed Coupling with Organotin and Organozic Reagents
Jessie Sandosham and Kjell Undheim*
*Department of Chemistry, University of Oslo, P.O.Box 1033, Blindern, N-0315 Oslo, Norway
Abstract
Pyrimidinyl triflates have been synthesized from pyrimidinones using triflic anhydride in the presence of triethylamine. The triflates, in the pyrimidine electrophilic positions, are versatile intermediates for substitution reactions. Carbon substituents are readily introduced in any position by Pd-catalyzed coupling reactions between pyrimidinyl triflates and aryl- or alkenyltin or with the corresponding organozinc reagents. Organozinc reagents are generally more reactive in coupling reaction and will effect the introduction of alkyl substituents.
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■ A Short Synthesis of Enantiomerically Pure (+)-Eldanolide and (-)-cis-Whisky Lactone by Samarium Diiodide Promoted Fragmentation of γ-Halo Esters
Toshio Honda,* Shin-ichi Yamane, Koichi Naito, and Yukio Suzuki
*Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
A stereoselective synthesis of (+)-eldanolide and (-)-cis-whisky lactone in optically pure forms has been achieved by employing a regioselective fragmentation reaction of the γ-halo esters as a key step.
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■ Oxidation of Dioxopyprroline with m-Chloroperbenzoic Acid: Selective Formation of 2,3-Dioxo-1,4-oxazine
Takehiro Sano,* Kazuko Amano, Masaharu Seki, Hiroyuki Hirota, Jun Toda, Fumiyuki Kiuchi, and Yoshisuke Tsuda
*Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan
Abstract
Treatment of 4-ethoxycarbonyl-5-phenyl-1H-pyrrole-2,3-diones (1a-1e) and 4-benzoyl-1,5-diphenyl-1H-pyrrole-2,3-dione (1f) with m -chloroperbenzoic acid caused Baeyer-Villiger oxidation to give 2,3-dioxo-1,4-oxazines (2a-2f) in moderate yields, respectively. This conversion of the 1H-pyrrole-2,3-dione into the 2,3-dioxo-1,4-oxazine provides the first synthesis of monocyclic 2,3-dioxo-1,4-oxazine ring system.
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■ Asymmetric Synthesis of a Homochiral Δ2-Isoxazoline Amino Acid Derivative
Bernadette M. Kelly-Basetti, Maureen F. Mackay, Suzanne M. Pereira, G. Paul Savage,* and Gregory W. Simpson
*CSIRO, Divisuon of Chemicals & Polymers, Private Bag 10, Rosebank MDC, Clayton Vic. 3169, Austalia
Abstract
(2R)-4Methylene-2-phenyl-3-propionyloxazolidin-5-one underwent 1,3-dipolar cycloaddition with 2,6-dichlorobenzonitrile oxide to give (5S,7R)-3-(2,6-diphenyI)-7-phenyl-6-propionyl-2,6-diaza-1,8-dioxaspiro[4.4]non-2-en-9-one, a protected isoxazoline amino acid. The reaction proceeded regiospecifically and with high stereoselectivity. The anti addition product predominated. The regiochemistry of addition was determined by nmr and the stereochemistry of addition was determined by X-ray analysis. The transition state energies for syn and anti addition were calculated using the semi-empirical AM1 method in the MOPAC package.
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■ First Preparation, Structural Determination by X-Ray Crystallographic Analysis and MO-Calculations of Dibenzo[bc,fg][1,4]dithiapentalene and Its Selenium Analogs
Takeshi Kimura, Yasuhiro Ishikawa, Yoshihiro Minoshima, and Naomichi Furukawa*
*Department of Chemistry, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan
Abstract
Dibenzo[bc,fg][1,4]dithiapentalene and its selenium analogs were prepared by thermolysis and photolysis of 1,9-disubstituted dibenzochalcogenophenes. The X-ray crystallographic analysis of dibenzochalcogenapentalenes revealed clearly that they have completely planar forms. PM3 molecular orbital (PM3 MO) calculation of pentalenes was carried out and their highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) were determined.
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■ Reduction of Aromatic Nitroalkenes with Baker's Yeast
Mitsuhiro Takeshita,* Sachiko Yoshida, and Yoichiro Kohno
*Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan
Abstract
Aromatic nitroalkenes were reduced chemoselectively with baker’s yeast to give the corresponding nitroalkanes.
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■ Novel Synthesis of Pyrido[3,4-d]pyrimidines, Pyrido[2,3-d]pyrimidines, and Quinazolines via Palladium-catalyzed Oxidative Coupling
Kosaku Hirota,* Hideki Kuki, and Yoshifumi Maki
*Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan
Abstract
Oxidative-coupling of 6-azavinyl(or vinyl)-1,3-dimethyluracil derivatives (1, 5, and 7) with electron-deficient olefins in the presence of palladium acetate led to the formation of the corresponding 6-substituted pyrido[3,4-d]pyrimidines (4), pyrido[2,3-d]pyrimidines (6), and quinazolines (8 and 9), respectively, via an intermediacy of azatriene.
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■ Substituted 1,2,3-Triazolium-1-ylides as 1,3-Dipoles: Synthons for a Range of Azimine and 1,2,3-Triaza Systems
Richard N. Butler* and Donal F. O'Shea
*Chemistry Department, University College Galway, Ireland
Abstract
The synthetic scope of the 1,2,3-triazolium-1-ylide system as a 1,3-dipole is outlined.
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■ Bicyclic Compounds Structurally Related to Dehydroacetic Acid and Triacetic Acid Lactone
Marcial Moreno-Mañas* and Roser Pleixats
*Department of Chemistry, Universitat Autònoma de Barcelona, Bellaterra. 08193-Barcelona, Spain
Abstract
The preparation and reactivity of bicyclic compounds derived from dehydroacetic acid and triacetic acid lactone are reviewed.
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■ Further Researches on the Furoclerodanes from Teucrium Species
Franco Piozzi*
*Dipartimento di Chimica Organica, Università di Palermo, Via Archirafi 20 90123 Palermo, Italy
Abstract
The review updates the advances reported during the last six years on the chemistry of these diterpenoids.
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■ Complexes of Carboxylic Acids with Pyridines and Pyridine N-Oxides
Zofia Dega-Szafran and Miroslaw Szafran*
*Facluty of Chemistry, Adam Mickiewicz University, ul. Grunwaldzka 6, 60-780 Poznán, Poland
Abstract
A brief survey is given of dielectric, spectroscopic, thermodynamic, colligative and conductivity properties of non-aqueous solutions of carboxylic acid complexes with pyridines and pyridiie N-oxides. Selected problems of solid state are also reviewed. Solvent and isotopic effects, and the problem of localization of the H-bonded proton are stressed.