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. 5, 1996
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■ A Facile Synthesis of 4,4-Bis(trifluoromethyl)imidazolines via a Novel Oxidative Imidazole Rearrangement
Hui-Yin Li *, Indawati Delucca, Spence Drummond, and George A. Boswell
*The DuPont Merck Pharmaceutical Company, Chemical Sciences Division Experimental Station, Wilmington, DE 19880-0353, U. S. A.
Abstract
Oxidation of imidazole (1) with singlet oxygen or m-chloroperbenzoic acid affords novel 4,4-bis(trifluoromethyl)imidazolines in high yield via a unique oxidative ring opening and subsequent acid catalyzed dehydrocyclization.
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■ A Convenient Synthesis of Heteroquaterphenoquinones Including Novel Nitrogen- and Selenium-containing Quinones with Characteristic Properties
Kazuko Takahashi* and Atsushi Gunji
*Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-77, Japan
Abstract
A series of heteroquaterphenoquinones including novel biselenieno- and bi-N-methylpyrrolo-quinonoid incorporated quinones have been synthesized by a novel one-pot oxidative homocoupling reaction of heterocycle-substituted phenols. Characteristic properties adequate for using as functional materials have been clarified.
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■ Stereochemical Analysis of Transannular [2,3]-Wittig Rearrangement of 12-Membered Cyclic Ether Based on Rigid MM2 Transition State Model
Takashi Takahashi,* Hiroshi Tanaka, Yasuharu Sakamoto, and Haruo Yamada
*Department of Chemical Engineering, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152, Japan
Abstract
Transannular [2,3]-Wittig rearrangement of the 12-membered cyclic ether, a key reaction to construct the 9-membered masked enediyne of kedarcidin chromophore, and a discussion of its diastereoselectivity based on a rigid MM2 transition state model are described.
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■ Ilicifoline: New Berbine Dimer Alkaloid from Berberis iIicifolia
Victor Fajardo *, Claudia Cárcamo, and Bárbara Moreno
*Universidad de Magallanes, Facultad de Ciencias, Punta Arenas, Chile
Abstract
From Berberis ilicifolia, a new dimer is described, but this alkaloid is related to a bisberbine. It is the first dimer of this type in Berberis.
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■ Simple Synthetic Method of Dialkyl 1,2-Dihydro(iso)quinoline (1 or 2)-Phosphonates
Michiharu Sugiura, Koosuke Asai,* and Yoshiki Hamada
*Faculty of Pharmacy, Meijo University, Yagotoyama, Tempaku-cho, Tempaku-ku, Nagoya 468, Japan
Abstract
1,2-Dihydro(iso)quinoline-2 (or 1)-phosphonates were synthesized from (iso)quinoline, sulfonyl chloride and trialkyl phosphite in CH2Cl2 at room temperature for 1 day in high yields.
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■ Regio- and Stereochemical Control in the Photodimerization of Methyl 3-(2-Furyl)acrylate
Maurizio D'Auria
*Dipartimento di Chimica, Università della Basilicata, Via N. Sauro 85, 85100 Potenza, Italy
Abstract
The photochemical dimerization of methyl 3-(2-furyl)acrylate in acetonitrile in the presence of benzophenone as triplet sensitizer was reinvestigated in order to understand regio- and stereochemical control. Hplc purification of the dimers and 1H-nmr data allow to correct a wrong structural assignment for a dimer found in the reaction. Regiochemical control can be understood on the of frontier orbitals interaction. Stereochemical control depends on the stability of the dimers. All these data were obtained by the use of the AM1 semiempirical method.
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■ Studies of Constituents of Saururus chinensis
Eie-Ching Wang*, Ming-Huei Shih, Mon-Chun Liu, Ming-Tyan Chen, and Gene-Hsiang Lee
*Department of Applied Chemistry, Chia Nan Junior College of Pharmacy, Tainan, Taiwan, R.O.C.
Abstract
Extracts of Saururus chinensis (Lour.) Baill. (Saururacease) plants were partitioned. The chloroform fraction showed the most potent anti-hypertension effect. Constituents of this fraction include a new lignan, sauchinone, three anthraquinone derivatives and an alkaloid.
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■ Preparation of 8,16-Imino-8H,16H-dinaphtho[2,1-b:2,1-f][1,5]dioxocin
Hala M. Refat, Ahmed A. Fadda, Yingchun Lu, and Edward R. Biehl*
*Chemistry Department, Southern Methodist University, Dallas, TX, 75205, U.S.A.
Abstract
A procedure for the synthesis of 8,16-imino-6H,14H-di-naphtho[2,1-b:2,1-f][1,5]dioxocin from the reaction of 2-hydroxy-1-naphthaldehyde with ammonium acetate is described.
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■ 1,2-Bis(azol-1-yl)ethanes. Deprotonation and Subsequent Reaction with Electrophiles.
Enrique Díez-Barra*, Antonio Herrera, Antonio de la Hoz, and Juan Tejeda
*Facultad de Química, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain
Abstract
Deprotonation of the title compounds and subsequent reaction with electrophiles have been performed. The main factor governing the reaction, substitution vs elimination, is the acidity of the ring hydrogen atoms.
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■ Synthesis of Pyrano[2,3-h]quinolines as Tricyclic Acronycine Analogues
Catherine Jolivet, Christian Rivalle, and Emile Bisagni*
*URA 1387 CNRS, Institut Curie, Section de Recherche, Bat 110, Centre Universitaire 91405 Orsay, France
Abstract
Preparation of pyrano[2,3-h]quinolines containing either a carboxylic acid function or an aminated chain on various positions was achieved. In the course of this investigation, an unusual behaviour of the 4-functionalized chloro- and methoxypyrano[2,3-h]quinoline derivatives towards nucleophiles has been characterized.
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■ Condensed 1,2,4-Triazines: Synthetic and Molecular Modeling Studies of 5,8-Dihydro-7-methylpyrazino[2,3-e]-1,2,4-triazines
Cherng-Chyi Tzeng *, Kuan-Han Lee, Yeh-Long Chen, and Tai-Chi Wang
*School of Chemistry, Kaohsiung Medical College, Kaohsiung City 807, Taiwan, R.O.C.
Abstract
5,8-Dihydro-7-methylpyrazino[2,3-e]-1,2,4-triazines (dihydroazapteridines) were prepared by Hinsberg reaction of 5,6-diamino-1,2,4-triazines with bromoacetone via a regiospecific fashion. The initial Z-form Schiff base intermediates cyclized to give 5,6-dihydro-7-methylpyrazino[2,3-e]-1,2,4-triazines which underwent π redistribution to afford 5,8-dihydro-7-methylpyrazino[2,3-e]-1,2,4-triazines as final products.
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■ 1H- and 13C-Nmr Spectral Data of Five Sarpagine-type Alkaloids
Reija Jokela and Mauri Lounasmaa*
*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, FIN-02150 Espoo, Finland
Abstract
Revised 1H- and 13C-nmr spectral data are presented for normacusine B (1), E-akuammidine (2), pericyclivine (3), polyneuridine (4), and voachalotine (5).
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■ 1,3-Dipolar Cycloaddition of Nitriles under Microwave Irradiation in Solvent-Free Conditions
Angel Díaz-Ortiz *, Enrique Díez-Barra, Antonio de la Hoz, Andrés Moreno, Maria J. Gómez-Escalonilla, and André Loupy
*Facultad de Química, Universidad de Castilla-La Mancha, E-13071 Ciudad Real, Spain
Abstract
Several nitriles were allowed to react with nitrones or nitrile oxides in the absence of solvent under microwave irradiation within 2-10 min to give 2,3-dihydro-1,2,4-oxadiazoles or 1,2,4-oxadiazoles, respectively.
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■ Asymmetric Synthesis of Benzylic Quaternary Carbon Center via an Enzymatic Reaction
Shunsaku Shiotani,* Hirohiko Okada, Kumiko Nakamata, Takako Yamamoto, and Fumie Sekino
*Department of Chemistry, Faculty of Science, Toyama University, Gofuku 3190, Toyama 930, Japan
Abstract
(R)-(+)-((R)-(+)-12) and (S)-(-)-1-formyl-1-methyl-7-methoxy-1,2,3,4-tetrahydronaphthalene ((S)-(-)-12) were synthesized based on enantioselective PLE hydrolysis of diethyl 2-(m-methoxyphenyl)-2-methylmalonate. From (R)-(+)-12, (+)-O-Methylaphanorphine (16) and (-)-aphanorphine were synthesized. (S)-(+)-1-(N-Acetyl-N-methylaminoethyl)-1-methyl-7-methoxytetralin (25) was synthesized from (S)-(-)-12. This transformation constitutes a formal synthesis of (-)-eptazocine.
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■ Synthesis and Polybromination of Azuleno[6,5-d]thiazole and It's 2-Methyl Derivatives
Tian-Chyuan Huang, Yun-Shan Lin,* and Tetsuo Nozoe
*Department of Chemistry, Tamkang University, Tamsui, Taipei, Taiwan, R.O.C.
Abstract
Azuleno[6,5-d]thiazole (5a) and its 2-methyl derivative (8) were obtained by the deethoxycarbonylation of the corresponding diethyl azuleno[6,5-d]thiazole-5,7-dicarboxylate (4a) and 2-methyl derivative (6b) which were synthesized from diethyl 2-acetylamino-6-aminoazulene-1,3-dicarboxylate (1) in a few steps. Polybromination of 5a and 8 in 10% aqueous THF led to the corresponding 5-bromo-7,9-azulenequinono[6,5-d]thiazole (9a) and 2-methyl derivative (9b), respectively.
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■ Synthetic Building Blocks Containing the 1,2-Diazine Moiety: N- and O-Protected 3-(4-Pyridazinyl)isoserines
Gottfried Heinisch,* Thierry Langer, Jacques Tonnel, Kurt Mereiter, and Klaus Wurst
*Institute of Pharmaceutical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria
Abstract
The synthesis of pyridazinylglycidates and pyridazinylimines as potential precursors of pyridazinylisoserine derivatives, is described. Reaction of the imines (6a,b) with α-silyloxyketene acetals in the presence of zinc chloride led to isoserine derivatives (7a,b) and (8a,b). The mixtures of diastereoisomers obtained were separated and configurations were determined by X ray analysis.
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■ A Synthesis of New Pyrido[2',3': 4,5]thieno[2,3-c]pyridazine Derivatives
Ma. Carmen Veiga, José Ma. Quintela,* and Carlos Peinador
*Departamento de Química Fundamental e Industrial, Facultad de Ciencias, Universidad de La Coruña, Campus de A Zapateira, E-15071, La Coruña, Spain
Abstract
5-Amino-3,4-diphenylthieno[2,3-c]pyridazine-6-carbaldehyde is formed by DIBAL reduction from the corresponding cyano precursor 5-amino-3,4-diphenylthieno[2,3-c]pyridazine-6-carbonitrile (1). A variety of substituted pyrido[2’,3’:4,5]thieno[2,3-c]pyridazines were synthesized from 5-amino-3,4-diphenylthieno[2,3-c]pyridazine-6-carbaldehyde (2) by Friedländer condensation with acyclic cyclic, heterocyclic or α,β-unsatured ketones and other active methylene compounds.
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■ The Chemistry of Trichloroacetonitrile
Sherif M. Sherif and Ayman W. Erian*
*Department of Chemistry, Faculty of Science, Cairo University, Giza, A. R. Egypt
Abstract
Trichloroacetonitrile (TCAN) is a versatile reagent in organic synthesis which has drawn the interest of synthetic and theortical chemists. In this review, literature reports are organized to fill what was an obvious gap by providing an overview of the subject.