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
Barry M. Trost's Special Issues, Vol. 67, No. 2, 2006
Published online: 18th October, 2005
■ Facile Preparation of Substituted Benzimidazole-2-carboxylates
Yongbao Zhu, Krystyna A. Skupinska, and Ernest J. McEachern*
*Department of Chemistry, AnorMED, Inc., #200-20353 64th Ave., Langley, B. C., V2Y 1N5, Canada
Abstract
Mild conditions for the preparation of benzimidazole-2-carboxylates have been developed. Condensation of a substituted 1,2-phenylenediamine with methyl trichloroacetamidate in the presence of TFA rapidly affords the 2-trichloromethylbenzimidazole; hydrolysis provides the desired product.
Published online: 8th November, 2005
■ Regioselective Synthesis of 4-Alkylpyridines from Pyridine and Aldehydes via Dipole Reversal Process of 1,4-Dihydropyridine Phosphonate
Phil Ho Lee,* Kooyeon Lee, Jun Hwan Shim, Seong Guk Lee, and Sundae Kim
*Department of Chemistry, Kangwon National University, Chuncheon, Kangwon 200-701, Korea
Abstract
4-Alkylation of pyridine has been accomplished by the reaction of ylides, derivated from 1,4-dihydropyridine phosphonate via phosphonioalkoxycarbonylation of pyridine with aldehydes and subsequent elimination of diisopropyl phosphate followed by aromatization with potassium tert-butoxide.
Published online: 8th November, 2005
■ Synthesis and Spectral Properties of Azaterrylene Dicarboximide Derivative
Yukinori Nagao, Yuko Ogihara, Masafumi Adachi,* and Kozo Kozawa
*Department of Industrial Chemistry, Faculty of Science and Technology, Science University of Tokyo, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
Abstract
Azaterrylene dicarboximide derivative was prepared by the coupling of N-pentyl-9-tributylstannylperylene-1,8-dicarboximide with 5-bromo-1,8-dimethylisoquinoline in the presence of Pd(PPh3)4 and following ring closure reaction by using t-BuOK/DBN. Spectral properties in solution were investigated and analyzed by molecular orbital method.
Published online: 30th September, 2005
■ Metachromins J and K, New Sesquiterpenoids from Marine Sponge Spongia Species
Yohei Takahashi, Masashi Tsuda, Jane Fromont, and Jun’ichi Kobayashi*
*Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812, Japan
Abstract
Two new cytotoxic sesquiterpenoids, metachromins J (1) and K (2), have been isolated from an Okinawan marine sponge Spongia sp. (SS-1037). The structures of 1 and 2 were elucidated on the basis of the spectroscopic data.
Published online: 18th November, 2005
■ Pyridine-derived Heterocycles as Potential Photoacylating Reagents
Céline Helgen and Christian G. Bochet*
*Department of Chemistry, University of Fribourg, 9 Ch. du Musée, CH-1700 Fribourg, Switzerland
Abstract
We prepared several pyridine-derived heterocycles and investigated their photoacylating properties. Among representatives of 4 families of compounds (1-acetyl-7-azaindole, 1-acetyl-7-azaindoline, 2-acetamindpyridine and 2-amidopyrimidines), the 2-aminopyrimidine derivatives were the most promising candidates. Photoacylation of dodecylamine yields up to 47% were obtained, upon irradiation with UV light at 254 nm.
Published online: 28th October, 2005
■ Novel Methods of Synthesizing Naphtho[1,2-c]furan-1,3-dione and Benzo[e]isoindole-1,3-dione
Masahiro Mizuno* and Mitsuhisa Yamano
*Chemical Development Laboratory, Takeda Chemical Industries, Ltd., 17-85 Jusohonmachi 2-chome, Yodogawa-ku, Osaka 532-8686, Japan
Abstract
Convenient methods of synthesizing naphtho[1,2-c]furan-1,3-dione and benzo[e]isoindole-1,3-dione from phenylbutyric acid derivatives have been established. Naphtho[1,2-c]furan-1,3-dione and benzo[e]isoindole-1,3-dione were obtained respectively from 4,5-dihydronaphtho[1,2-c]furan-1,3-dione and 4,5-dihydrobenzo[e]isoindole-1,3-dione by aromatization with 10% Pd-C in AcOH under mild conditions. In addition, benzo[e]isoindole-1,3-dione derivatives were obtained from 4,5-dihydronaphtho[1,2-c]furan-1,3-dione by imidation and simultaneous aromatization with primary amine in AcOH in one pot.
Published online: 14th October, 2005
■ Cycloaddition Reactions of 1-Azadienes Derived from Hydrazones with Electron-deficient Dienophiles
Francisco Palacios,* Domitila Aparicio, Yago Lópes, and Jesús M. de los Santos
*Departamento de Química Orgánica I, Facultad de Farmacia, Universidad del País Vasco, Apto. 450, 01080 Vitoria, Spain
Abstract
The aza-Diels-Alder reaction of 1-aza-1,3-butadienes derived from hydrazones, with electron-deficient dienophiles is reported. When there is not substitution at C-2 in the starting 1-azadiene, fused-pyridine derivatives are obtained. However, the use of 1-azadienes substituted with a methyl group at C-2 gave the corresponding pyridazinone derivative.
Published online: 30th September, 2005
■ Phosphate Mimic of Nucleotides, Conformational Influences on the Ribofuranose Conformations
Arnaud Gautier
*IRCOF-UPRES A 6014, Faculty of Sciences, University of Rouen, Rue Tesnières, F-76821 Mont Saint Aignan Cedex, France
Abstract
The influences of the modifications of the natural nucleotides is rationalized in terms of stereoelectronics effects. This article reviews the pseudorotation concept and the Generalized Karplus Type equation used to quantify the conformational behavior of ribofuranose in solution.