Regular Issue

Vol. 31, No. 2, 1990

25 data found. 1 - 25 listed
Communication | Regular issue | Vol 31, No. 2, 1990, pp.191-195
Published online:
DOI: 10.3987/COM-89-5216
Synthesis of (2S,4S)- and (2S,4R)-4-Substituted Glutamic Acid Analogues for Neuroexcitatory Activity Studies

Yung-Son Hon,* Yen-Chung Chang,* and Ming-Li Gong

*Institutue of Chemistry, Academia Sinica, 128, Yan-Chiu-Yuan Road, Sec II, Nankang, Taipei,11529, Taiwan, R.O.C.

Abstract

The stereospecific syntheses of various length 4(R)- and 4(S)-substituted 2(S)-glutamic acid were described.

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Communication | Regular issue | Vol 31, No. 2, 1990, pp.197-202
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DOI: 10.3987/COM-89-5217
A Theoretical Study of the Structure and Tautomerism of 1,2,4,6-thiatriazine 1,1-Dioxide

José Elguero,* José Luis G. de Paz, Pilar Goya, Juan Antonio Páez, and Isabel Rozas

*Instituto de Química Médica, C. S. I. C., Calle Juan de Cierva, 3, 28006 Madrid, Spain

Abstract

"Ab initio" theoretical Calculations have been used to study the structure and annular tautomerism of 2(4)H-1,2,4,6-thiatriazine 1,1-dioxide. The 4H-tautomer has been found to be the most stable in agreement with 1H-, 13C- and 15N-nmr data.

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Communication | Regular issue | Vol 31, No. 2, 1990, pp.203-209
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DOI: 10.3987/COM-89-5248
Molecular Yardsticks: Synthesis of Higher Homologs of 7,12-Dihydropyrido[3,4-b:5,4-b’]diindole. Probing the Dimensions of the Benzodiazepine Receptor Inverse Agonist Site

Krishnaswamy Narayanan and James M. Cook*

*Department of Chemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, U.S.A.

Abstract

The synthesis of some of the higher homologs 7,12-dihydropyridodiindole 2, eg. diindoles 3, 4, 6, and 7, via a thermally induced Fischer indole cyclization of 1 with the appropriate naphthylhydrazines and quinolylhydrazines is described. These pyridodiindoles are to be used as molecular yardsticks in defining the spatial dimensions of the benzodiazepine receptor inverse agonist site.

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Communication | Regular issue | Vol 31, No. 2, 1990, pp.211-214
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DOI: 10.3987/COM-89-5256
Facile Synthesis of Tetrahydro-2-furylated Pyrimidines and Purines Using a New Catalyst of Cesium Chloride

Chun Ho Lee, Joong Young Kim, Wan Joo Kim, and Yong Hae Kim*

*Department of Chemistry, Korea Advanced Institute of Science and Technology, P. O. Box 150, Cheong-ryang, Seoul 130-650, Korea

Abstract

1-(Tetrahydro-2-furyl)pyrimidine and 9-(tetrahydro-2-furyl)purine derivatives were successfully synthesized in good yields by the reactions of trimethylsilylated pyrimidine and purine bases with 2-acetoxytetrahydrofuran using a new catalyst of cesium chloride in acetonitrile under mild conditions.

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Communication | Regular issue | Vol 31, No. 2, 1990, pp.215-218
Published online:
DOI: 10.3987/COM-89-5258
Alkylative Lactonization of γ,δ-Unsaturated Esters with α-Chloro Sulfides. A Concise Synthesis of the Monoterpene Lactone from Chrysanthemum flosculosum L.

Hiroyuki Ishibashi,* Hiroshi Nakatani, Taru Su So, Toyokazu Fujita, and Masazumi Ikeda

*Kyoto Pharmaceutical University, Misasagi, Yamashina, Kyoto 607-8414, Japan

Abstract

The γ,δ-unsaturated ester 1, on being treated with α-chloro sulfides 2 in the presence of SnCl4, underwent an alkylative lactonization to give the δ-lactones 3. This method was applied to the synthesis of the monoterpene lactone 4 isolated from Crysanthemum flosculosum L.

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Communication | Regular issue | Vol 31, No. 2, 1990, pp.219-221
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DOI: 10.3987/COM-89-5268
Reaction of Aryl Halides with (Z)-1-Ethoxy-2-tributylstannylethene: A Versatile Method for the Introduction of 2-Ethoxyethenyl Group into Aromatic Nuclei

Takao Sakamoto, Yoshinori Kondo, Akito Yasuharu, and Hiroshi Yamanaka*

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan

Abstract

The reaction of 4-substituted bromobenzenes, except for 4-bromophenol and 4-bromoaniline, with (Z)-1-ethoxy-2-tributylstannylethene is well prompted by the catalytic action of dichlorobis(triphenylphosphine)palladium in dimethylformamide in the presence of tetraethylammonium chloride to give (Z)-1-ethoxy-2-(4-substituted phenyl)ethene. The method is also useful for the introduction of a 2-ethoxyethenyl moiety into heteroaromatic ring s such as pyridine, thiophene, indole.

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Communication | Regular issue | Vol 31, No. 2, 1990, pp.223-227
Published online:
DOI: 10.3987/COM-89-5270
Development of a Hydrazine-mediated System for the Reductive Activation of Mitomycin C

David J. Russell and Harold Kohn*

*Department of Chemistry, University of Houston, Houston, TX 77204-5641, U.S.A.

Abstract

The reactivity of mitomycin C (1) with hydrazines (2) has been examined. Monoarylhydrazines have been shown to efficiently reduce 1 leading to the activation of both proposed DNA binding sites (C-1 and C-10) within the drug.

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Communication | Regular issue | Vol 31, No. 2, 1990, pp.229-232
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DOI: 10.3987/COM-89-5286
Total Synthesis of (-)-Eudistomin F

Jin-Jun Liu, Masako Nakagawa,* Naoyuki Harada, Akihiko Tsuruoka, Atsushi Hasegawa, Jian Ma, and Tohru Hino*

*Faculty of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan

Abstract

(-)-Eudistomin F (1d) was synthesized in optically pure form from 6-bromo-5-methoxy-Nb-hydroxytryptamine (10) and D-cysteinal (15).

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.233-240
Published online:
DOI: 10.3987/COM-89-4896
Synthesis of (4’R)- and (4’S)-5-(2’,2’-Dimethyl-1’,3’-dioxolan-4’-yl)-3-phenyl-4,5-dihydro-1,2,4-oxadiazoles and (4’R)-5-(2’,2’-Dimethyl-1’,3’-dioxolan-4’-yl)-3-phenyl-1,2,4-oxadiazole

Louis Cottier, René Faure, Gérard Descotes,* and Rajendrra Mohan Srivastava

*Laboratoire de Chimie Organique II, Université Lyon I, U. A. CNRS 463, 43 Boulevard du 11 Novembre 1918, 69622 Villeurbanne, France

Abstract

Chiral 3,5-disubstituted 4,5-dihydro-1,2,4-oxadiazoles (3, 4) have been prepared starting from benzamidoxime (1) and (R)-(-)-2,3-O-isoproppylideneglyceraldehyde (2). The structure of 3 was establised as (4’R)-5-(2’,2’-dimethyl-1’,3’-dioxolan-4’-yl)-3-phenyl-4,5-dihydro-1,2,4-oxadiazole by X-ray diffrection analysis on a single crystal. Mild possassium permanganate oxidationof a mixture of 3 and 4 gave the corresponding 1,2,4-oxadiazole (5).

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.241-246
Published online:
DOI: 10.3987/COM-89-4999
A Simple Route to 3-Amino-1,4-dimethyl-6-hydroxy- (or methoxy-)carbazoles

Jean-Charles lancelot, Bertrand Letois, Sylvain Rault, and Max Robba*

*Laboratoire de Chimie Thérapeutique, U. F. R. des Sciences Pharmaceutiques, Université de Caen, 1, rue Vaubénard, 14032 Caen Cedex, France

Abstract

A convenient synthesis of 3-amino-1,4-diemthyl-6-hydroxy- (or methoxy-)carbazoles was described starting from 1,4-dimethyl-6-hydroxycarbazoles. Structures were confirmed by unequivocal synthesis.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.247-253
Published online:
DOI: 10.3987/COM-89-5045
Synthesis and Cycloaddition Reaction of N-Phenyl-C-styrylmethanohydrazonyl Bromide

Hamidi M. Hassaneen,* Ahmad S. Shawali, and Nehal M. Elwan

*Department of Chemistry, Faculty of Science, University of Cairo, Giza, Egypt

Abstract

N-Phenyl-C-styrylnitrilimine 4 reacts with arylidenesulphonylacetonitriles 5a-c or arylidenemalononitriles 6a-c to give exclusively 5-cyanopyrazoles 9a-c. On the other hand cylcoaddition of ethyl arylidenecyanoacetate 11a,c, α-cyanoarylideneacetophenones 12b-d and benzylidene α-cyanoacetanilide 13a with 4 yields 2-pyrazoline derivatives 14a,c, 15b-d, and 16a, respectively. Also, nitrilimine 4 reacts with N-arylmaleimides 18a-d to give the corresponding pyrrolopyrazoles 19a-d.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.255-258
Published online:
DOI: 10.3987/COM-89-5121
Synthesis of C-8 Prenylated and Angular 3-(1’,1’-Dimethylallyl)coumarins

Javier Salvá, Francisco Rodríguez Luis, Enrique Pando, Guillermo Martínez Massanet, and Rosario Hernández Galán

*Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Cádiz, Apartado 40, Puerto Real Cádiz, Spain

Abstract

The natural coumarins ramosinin (1) and 3-(1’,1’-dimethylallyl)-8-(3",3"-dimethylallyl)xanthyletin (2) have been synthesized from umbelliferone. The synthesis of the angular derivatives 3-(1’,1’-dimethylallyl)columbianetin (9) and 3-(1’,1’-dimethylallyl)lomatin (10) was also achiebed.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.259-265
Published online:
DOI: 10.3987/COM-89-5148
New Tricyclic Compounds : Pyrdio[2’,3’:4,5]- and Pyrdio[3’,2’:4,5]imidazo[1,2-a]pyrimidines

Denis Descours and Didier Festal*

*LIPHA, centre de recherche, BP 8481, 69359 Lyon Cedex 08, France

Abstract

1,2,3,4-Tetrahydropyrido[2’,3’:4,5]imidazo[1,2-a]pyrimidin-2-ones 1 are synthesized from 3-amino-2-benzylaminopyridines by condensation with N-(3-chloropropanoyl)carbonimidic dichloride and subsequent cyclisation. 1,2,3,4-Tetrahydropyrido[2’,3’:4,5]imidazo[1,2-a]pyrimidin-2-ones 2 are prepared from methyl N-(3-amino-2-pyridyl)-3-aminopropanoates by condensation with N-acetylcarbonimidic dichloride, hydrolysis and cyclisation. Alkylation of pyridoimidazo[1,2-a]pyrimidin-2-ones 1 or 2 gives the corresponding 1-alkyl derivatives.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.267-276
Published online:
DOI: 10.3987/COM-89-5197
Reactions of 1,2-Diaminobenzimidazoles with β-Dielectrophiles: Synthesis of Pyrimido[1,2-a]benzimidazole Derivatives

Claudia Romano, Elena de la Guesta, and Carmen Avendaño*

*Departamento de Química OrgÁnica y Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain

Abstract

1,2-Diaminobenzimidazoles react with malonic and β-ethoxymethylenemalonic acid derivatives to give pyrimido[1,2-a]benzimidazole derivatives.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.277-281
Published online:
DOI: 10.3987/COM-89-5219
Synthesis of 8-Nitro- and 7-Methoxy-8-nitro-1,2,4-triazolo[1,5-c]pyrimidines

Olivier Rousseaux, Dominique Blondeau, and Henri Sliwa*

*Laboratoire de Chimie Organique Physique, Université des Sciences et Technologies de Lille, Flandres-Artois, F 59655 Villeneuve d’ Ascq Cedex, France

Abstract

4-Hydrazino-5-nitropyrimidine and its 6-methoxy derivative were condensed under heating with ethyl orthoformate to afford the title compounds through the intermediacy of an imino ether. In both cases the first formed 1,2,4-triazolo[4,3-c]pyrimidines were not isolated and directly converted to their [1,5-c] isomer by a Dimroth rearrangement.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.283-287
Published online:
DOI: 10.3987/COM-89-5224
Synthesis of (±)-Physovenine and (±)-7-Bromophysovenine from Intermediates of the Synthesis of Physostigmines

Yi-lin Luo, Qian-sheng Yu, Linda Chrisey, and Arnold Brossi*

*Section of Medical Chemistry, Laboratory of Analytical Chemistry, NIDDK, National Institute of Health, Bethesda, MD 20982, U.S.A.

Abstract

Facile synthesis of (±)-physovenine (1) was accomplised from oxindole 3, an intermediate in Julian’s total synthesis of physostigmines (2A and 2B). C-Alkylation of 3 with methyl bromoacetate afforded ester 4 which was reduced with LAH in THF at 0 °C to directrly afford tetrahydrofuroindole 6. Ether cleavage of 6 with BBr3 in dichloromethane afforded phenol 7, and (±)-physovenine (1) on treatment of 7 with methyl isocyanate in ehter. Bromination of 1 with bromosuccinimide in methanol afforded (±)-7-bromophysovenine (8).

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.289-304
Published online:
DOI: 10.3987/COM-89-5229
Reactivity of Substituted N-Aminopyridinium Salts and Their Benzologues. A Novel Approach to s-Triazolo[1,5-a]quinolinium and s-Triazolo[5,1-a]isoquinolinium Derivatives

Sándor Bátori, Péter Sándor, and András Messmer*

*Central Research Institute for Chemistry, Hungarian Academy of Sciences, H-1525 Budapest, P.O.Box 17, Hungary

Abstract

The reaction of 1-amino-2-cyanopyridinium perchlorate (1) with triethyl orthoformate gave an ethyl iminoformate derivative (2) which resulted in formation of a 1-iminopyrido-as-triazinium salt (3) in reaction with primary amine, and a formamidino derivative (4) with morpholine gave 2,3-diaza-1,3,5,7-octatetraene (5). The two benzologues of 1,N-aminoquinolinium (9) and N-aminoisoquinolinium (19) gave ethyl iminoformates (10 and 20) and formamidines (14 and 23). In reactions with primary amines these compounds led to s-triazolo[1,5-a]quinolinium (16) and [5,1-a]isoquinolinium (25) salts, respectively.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.305-319
Published online:
DOI: 10.3987/COM-89-5236
Chemical Modification of Erythromycins VII. Molecular Rearrangement Observed during Chemical Modification Study of the Desosamine Unit of Erythromycins

Shigeo Morimoto, Takashi Adachi, Yoshiaki Watanaba,* and Sadafumi Omura

*Research Center, Taisho Pharmaceutical Co., Ltd., 1-403 Yoshino-Cho, Ohmiya, Saitama 330-8530, Japan

Abstract

The reaction of 2’-O-methanesulfonylerythromycin A derivatives (2) with a variety of nucleophilic reagents gave 2’-dimethylamino-3’-substituted derivatives (3). The reaction took place with neighboring group-participated nucleophilic substitution involoving migration of participating 3’-dimethylamino group. This migration was also observed in the case of N-oxide of the dimethylamino group.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.321-326
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DOI: 10.3987/COM-89-5242
The Synthesis of 6-C-Substituted Purines via α-(Aminomemthylene)-6-purineacetonitrile

Norimitsu Hamamichi and Tadashi Miyasaka

*School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142, Japan

Abstract

6-Purinemalononitrile (3), which was prepared by the substitution of 6-chloropurine (1) with malononitrile or deprotection of methoxymethyl group of (9-methoxymethyl-purin-6-yl)malononitrile (2) with acid, has been catalytically hydrogenated to the α-(aminomethylene)-6-purineacetonitrile (4). Substitution of 4 with hydrazine and acetamidine hydrochloride gave pyrazole derivative (7) and pyrimidine derivative (8), respectively.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.327-339
Published online:
DOI: 10.3987/COM-89-5244
The Use of Phosphonitrilic Dichloride Cyclic Trimer in Oligopeptide Synthesis. Synthesis of Isoxazolyl-Prodrugs of Netropsin and Distamycin

Erik J. Verner, Bradford J. Oliver, Ludwig Schlicksupp, and Nicholas R. Natale*

*Department of Chemistry, University of Idaho, 301 Renfrew Hall, Moscow, ID 83844-2343, U.S.A.

Abstract

Phosphonitrilic dichloride cyclic trimer has been found to be an effective activating agent for the synthesis of oligopeptides containing N-terminal isoxazole-4-carboxamide groups.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.341-351
Published online:
DOI: 10.3987/COM-89-5247
Synthesis of Aromatic Chloroberbines

Georges Memetzidis, Jean-françois Stambach,* and Louis Jung

*Laboratoire de Chimie Thérapeutique, U.F.R. des Sciences Pharmaceutiques, Université Louis Pasteur, 74, route du Rhin, BP 24, 67401 ILLKIRCH Cedex, France

Abstract

The introduction of chlorine atoms into aromatic rings of berbines was effected from an ethoxycarbamido group which does not undergo decomposition under the conditions of the Bischler-Napieralski reaction. At the end of he synthesis of the berbine ring system this group was transformed into a primary aromatic amine which was converted into chlorine by the Sandmeyer reaction. Thus berbines 6a,b chlorinated in the aromatic ring A and berbines 10a,b chlorinated in the aromatic ring D were prepared. The preparation of the starting β-phenethylamines 1a,b with an ethoxycarbamido group was also discussed.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.353-366
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DOI: 10.3987/COM-89-5250
Preparation of Enatiomerically Pure Decahydro-6H-isoquino[2,1-g][1,6]naphthyridines Utilizing the Openshaw-Whittaker Hexahydrobenzo[a]quinolizinone Resolution.

Robin D. Clark,* John R. Kern, Lilia J. Kurz, and Janis T. Nelson

*Institute of Organic Chemistry, Syntex Research, Palo Alto, California 94304, U.S.A.

Abstract

The (8aR,12aS,13aS)-decahydro-6H-isoquino[2,1-g][1,6]naphthyridine sulfonamides 1a,b were prepard from (+)-(3R,11bS)-3-cyanoethylhexahydrobenzo[a]quinolizinones 3a,b. These key intermediates were obtained by resolution of (±)-3a,b with (+)-camphorsulfonic acid in ethyl acetate accroding the the conditions used in the Openshaw-Whittaker synthesis of (-)-emitine.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.367-372
Published online:
DOI: 10.3987/COM-89-5253
Phosphorus Pentoxide in Organic Synthesis XXXX. Synthesis of 3-Aryl-3,7-dihydro-4H-pyrrolo[2,3-d]pyrimidin-4-ones

Khalid Mohamed Hassan Hilmy, Jørgen Mogensen, Anker Jørgensen, and Erik B. Pedersen*

*Department of Chemistry, Odense University, Campusvej 55 DK-5230 Odense M., Denmark

Abstract

Pyrrolo[2,3-a]pyrimidin-4(3H)-ones (2a-j) were prepared in 18-51% yields by heating 2-acetylamino-3-pyrrolocarbonitriles (1) with a mixture of phosphorus pentoxide, N,N-dimethylcyclohexylamine hydrochloride, water, and n appropriate arylamine hydrochloride at 180 °C.

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Paper | Regular issue | Vol 31, No. 2, 1990, pp.373-382
Published online:
DOI: 10.3987/COM-89-5260
Structure of Five New Prenylated Flavonoids L, M, N, O, and P from Aerial Parts of Glycyrrhiza uralensis

Toshio Fukai, Qing-Hua Wang, Mitsuo Takayama, and Taro Nomura*

*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan

Abstract

Five new prenylated flavonoids were isolated from the aerial parts of Glycyrrhiza uralensis FISCH. et DC. (Leguminosae), and the structures of the new compounds, gancaonins L, M, N, O, and P were elucidated as 8-prenylated 5,7,3’,4’-tetrahydroxyisoflavone, 8-prenylated 5,7-dihydroxy-8’-methoxyisoflavone, 6-prenylated 4’-methoxy-5,7,2’-trihydroxyisoflavone, 6-prenylated 5,7,3’,4’-tetrahydroxyflavone, and 6-prenylated 5,7,3’,4’-tetrahydroxyflavonol, respectively, on the basis of spectral evidence.

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Review | Regular issue | Vol 31, No. 2, 1990, pp.383-396
Published online:
DOI: 10.3987/REV-89-412
Reactions of the η5-Pyrrolyl Ligand: A New Challenge in the Chemistry of Pyrroles

Janusz Zakrzewski

*Institute of Chemistry, University of Lódz, 90-136 Lódz, Narutowicza 68, Poland

Abstract

This review describes reactions of the the η5-pyrrolyl ligand with special emphasis on their application in syntheses of substituted pyrroles.

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25 data found. 1 - 25 listed