Regular Issue

Vol. 43, No. 5, 1996

18 data found. 1 - 18 listed
Communication | Regular issue | Vol 43, No. 5, 1996, pp. 937 - 940
Published online:
DOI: 10.3987/COM-96-7418
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.


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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Communication | Regular issue | Vol 43, No. 5, 1996, pp. 941 - 944
Published online:
DOI: 10.3987/COM-96-7424
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


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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Communication | Regular issue | Vol 43, No. 5, 1996, pp. 945 - 948
Published online:
DOI: 10.3987/COM-96-7426
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


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 949 - 951
Published online:
DOI: 10.3987/COM-94-6909
Ilicifoline: New Berbine Dimer Alkaloid from Berberis iIicifolia

Victor Fajardo *, Claudia Cárcamo, and Bárbara Moreno

*Universidad de Magallanes, Facultad de Ciencias, Punta Arenas, Chile


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 953 - 958
Published online:
DOI: 10.3987/COM-95-7319
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


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 959 - 968
Published online:
DOI: 10.3987/COM-95-7367
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


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 969 - 975
Published online:
DOI: 10.3987/COM-95-7370
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.


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 977 - 983
Published online:
DOI: 10.3987/COM-95-7382
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.


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 985 - 994
Published online:
DOI: 10.3987/COM-95-7383
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


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 995 - 1005
Published online:
DOI: 10.3987/COM-95-7384
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


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 1007 - 1013
Published online:
DOI: 10.3987/COM-96-7387
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.


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 1015 - 1020
Published online:
DOI: 10.3987/COM-96-7401
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


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 1021 - 1030
Published online:
DOI: 10.3987/COM-96-7412
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


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 1031 - 1047
Published online:
DOI: 10.3987/COM-96-7421
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


(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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 1049 - 1056
Published online:
DOI: 10.3987/COM-96-7429
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.


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 1057 - 1071
Published online:
DOI: 10.3987/COM-96-7432
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


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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Paper | Regular issue | Vol 43, No. 5, 1996, pp. 1073 - 1081
Published online:
DOI: 10.3987/COM-96-7433
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


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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Review | Regular issue | Vol 43, No. 5, 1996, pp. 1083 - 1118
Published online:
DOI: 10.3987/REV-95-475
The Chemistry of Trichloroacetonitrile

Sherif M. Sherif and Ayman W. Erian*

*Department of Chemistry, Faculty of Science, Cairo University, Giza, A. R. Egypt


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.

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18 data found. 1 - 18 listed