Regular Issue

Vol. 24, No. 4, 1986

45 data found. 31 - 45 listedFirst Previous
Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1025 - 1029
Published online:
DOI: 10.3987/R-1986-04-1025
Novel Antimicrobial Agents Obtained by Addition of Maleimide Derivatives to Thenaldehyde Azines or Schiff’s Bases

Ali A. El-Emam,* Mohamed A. Moustafa, Hassan M. Eisa, and Mohamed M. El-Kerdawy

*Department of Medical Chemistry, Faculty of Pharmacy, University of Mansoura, Mansoura, Egypt

Abstract

Condensation of the azines of 2-thenaldehyde or 5-bromo-2-thenaldehyde with various N-arylmaleimides gave the 1:2 adducts 2,9-di(2-thienyl or 5-bromo-2-thienyl)-5,12-diaryl-1,5,8,12-tetraazatetracyclodecane-4,6,11,13-tetraones (1-6). Dehydrogenation of these adducts by boiling in nitrobenzene gave the dehydrogenated products (7-9). Fusion of a mixture of Schiff’s bases derived from 5-nitro-2-thenaldehyde or 5-nitrofurfural and aromatic amines with N-arylmaleimides in molar ratio 1:2 gave the spiro adducts 3,5’,8’,1’-tetrasubstituted 2,4,4’,6’-tetraoxo-spiro{pyrrolidin-1,2’-(octahydropyrrolo[3,4-c]pyrroles)} (10-19). The structures of the synthesized compounds were confirmed by elemental analysis, IR, 1H NMR and mass spectra. The preliminary antimicrobial testing of the prepared compounds against some pathogenic microorganisms proved that the spiro adducts particularly the compound (19) of great activity against Staph. aureus.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1031 - 1038
Published online:
DOI: 10.3987/R-1986-04-1031
An Efficient Regioselective Synthesis of 7-Substituted 1,3-Dimethyl-4-oxo-4H-1,3,4-thiadiazolo[2,3-c]-1,2,4-triazinium Cations

Pedro Molina,* Mateo Alajarín, and Francisco J. Navarro

*Departmento de Química Orgánica, Facultad de Ciencias, Universidad de Murcia, 30071 Murcia, Spain

Abstract

A number of 7-substituted 1,3-dimethyl-4-oxo-4H-1,3,4-thiadiazolo[2,3-c]-1,2,4-triazinium perchlorates 3 have been prepared by sequential treatment of 4-amino-2,6-dimethyl-5-oxo-3-thioxo-2,3,4,5-tetrahydro-1,2,4-triazine 1 with acyl chlorides and acetic anhydride/perchloric acid.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1039 - 1044
Published online:
DOI: 10.3987/R-1986-04-1039
Heterocyclic Spiro Compounds. I. Synthesis of 9,10-Dimethoxy-1,3,4,6,7,11b-hexahydrospiro[benzo[a]quinolizine-2,3’-pyrrolidine]-2’,5’-dione

J. Carlos Meréndez, Gregorio G. Trigo, and Mónica M. Söllhuber*

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

Abstract

The synthesis of 9,10-dimethoxy-1,3,4,6,7,11b-hexahydrospiro[benzo(a)quinolizine-2,3’-pyrrolidine]-2’,5’-dione (9) was achieved from the corresponding 2-benzo(a)quinolizidinone (2) by two different routes.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1045 - 1060
Published online:
DOI: 10.3987/R-1986-04-1045
Synthetic Studies of Detoxin Complex II: Syntheses of Detoxin B1 and B3

Bruce D. Harris, Krishna L. Bhat, and Madeleine M. Joullié*

*Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia, PA 19104-6323, U.S.A.

Abstract

Syntheses of title compounds from L-proline are described

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1061 - 1066
Published online:
DOI: 10.3987/R-1986-04-1061
Structures of Falconerine and Falconerine 8-Acetane, Two New C19-Diterpenoid Alkaloids

Haridutt K. Desai, Balawant S. Joshi, and S. William Pelletier*

*Department of Chemistry, Institute for Natural Products Research, The University of Georgia, Chemistry Building, Athens, Georgia 30602-2556, U.S.A.

Abstract

Two new alkaloids designated as falconerine (6) and falconerine 8-acetate (8) have been isolated from the Indian crude drug Mitha telia (Bish or Bikh), identified as Aconitum falconeri Stapf. The structures of these C19-diterpenoid alkaloids were derived from their spectral data and by correlation with ezochasmanine.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1067 - 1073
Published online:
DOI: 10.3987/R-1986-04-1067
An Improved and Divergent Introduction of the Streptonigrin and Lavendamycin Quinoline-5,8-quinone AB Ring Systems

Dale L. Boger*and Masami Yasuda

*Wetherill Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, U.S.A.

Abstract

An improved and divergent approach to the introduction of the streptonigrin and lavendamycin quinoline-5,8-quinone AB ring systems is detailed and is based on the selective and controlled nucleophilic substitution of common 7-bromoquinoline-5,8-quinone intermediates derived from the Friedländer condensation products of 2-amino-3-benzyloxy-4-bromobenzaldehyde.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1075 - 1078
Published online:
DOI: 10.3987/R-1986-04-1075
A New Synthesis of 3,5-Disubstituted Pyrazoles by Reaction of α,γ-Dipyrolidinylglutaronitriles (Masked α,γ-Diketone Equivalents) with Hydrazines

Kazumasa Takahashi,* Akira Suzuki, Katsuyuki Ogura, and Hirotada Iida

*Deparment of Synthetic Chemistry, Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan

Abstract

An efficient sequence proposed for a new synthetic method of 3,5-disubstituted pyrazoles involves the reaction of α,γ-dipyrrolidinylglutaronitriles (masked α,γ-diketone equivalents) with hydrazines.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1079 - 1093
Published online:
DOI: 10.3987/R-1986-04-1079
Reaction Paths and New Mechanistic Aspects of the Proton-catalyzed Reaction of 3-Alkylindoles with Arylaldehydes

Klaus Dittmann and Ulf Pindur*

*Department of Chemistry and Pharmacy, Institute of Pharmacy, University of Mainz, Saarstrasse 21, D-55122 Mainz, Germany

Abstract

The mechanism of the proton-catalyzed reaction of 3-alkylindoles with arylaldehydes is elucidated by the isolation of stable intermediates and products, and by the selective control of their transformations in the course of reaction. The aldehyde electrophile attacks at N1, C2 and C3 on the indole enamine structure with the temperature, the reaction time and the proton concentration controlling the relative quantities and distribution of products. It was established indirectly that an ipso-attack by intermediary cations with iminium and indolenine structure takes place at the 3-position of 3-alkylated indoles. This was made possible by the isolation of hitherto unknown tetrahydropyrrolodiindoles 14, 17. These compounds should be formed from intermediary indolylmethyl-indoleninium ions 13, 11, which are trapped by stereoelectronic controlled intramolecular cyclization.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1095 - 1098
Published online:
DOI: 10.3987/R-1986-04-1095
Oxidative 1,4-Dipolar Cycloaddition of Quinaldine N-Oxide with Dimethyl Acetylenedicarboxylate

Kazuko Wada, Kazuhisa Funakoshi, Seitaro Saeki, and Masatomo Hamana*

*Faculty of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan

Abstract

Quinaldine N-Oxide undergoes oxidative 1,4-dipolar cycloaddition with dimethyl acetylenedicarboxylate upon treatment with Tl(OAc)3 in acetonitrile or with DDQ in benzene, giving dimethyl quino[1,2-b][1,2]oxazine-2,3-dicarboxylate.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1099 - 1107
Published online:
DOI: 10.3987/R-1986-04-1099
Heterocycles. XIX. Reaction of 2’-Hydroxychalcones with Alkaline Hydrogen Peroxide

Hiroashi Takahashi, Yumiko Kubota, Lin Fang, and Masayuki Onda*

*School of Pharmaceutical Sciences, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan

Abstract

Reaction of 2’-hydroxychalcones, which contain the hydroxyl and/or the methoxyl group at the 4- and 6’-positions, with alkaline hydrogen peroxide has been examined. It is observed that these substituents intricately influence the formation of the products.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1109 - 1117
Published online:
DOI: 10.3987/R-1986-04-1109
Studies on the Chemical Transformation of Rotenoids. II. Reactions of Rotenone and Rotenonone with Primary Amines

Jinsaku Sakakibara,* Shin-ichi Nagai, Teppei Akiyama, Taisei Ueda, and Noriichi Oda

*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan

Abstract

The ring transformations of rotenone and rotenonone by primary amines were investigated. The improved synthetic methods for rotenonone were also developed. Rotenone (1) underwent cleavage of C-12a and O-13 linkage to give [1-(4-hydroxy-2-methylethenyl-2,3-dihydrobenzofuran-5-yl)-1-(6,7-dimethoxy-2H-chromen-4-yl)methylidene]alkylamines (2a-b), while rotenonone (5) gave 2-alkylcarbamoyl-4-alkylimino-8-methylethenyl-3-(2-hydroxy-4,5-dimethoxy)phenyl-8,9-dihydro-4H-furo[2,3-h][1]benzopyrans (7a-d) as a result of nucleophilic attack on C-12 carbon. Compound 1 was oxidized by nitrosyl chloride or dimethyl sulfoxide in the presence of iodine and sulfuric acid to provide retenonone (5) in improved yields respectively.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1119 - 1130
Published online:
DOI: 10.3987/R-1986-04-1119
Polycyclic N-Hetero Compounds. XXV. Synthesis of Novel D-homo-11,13,15-triazasteroidal Skeleton and Investigation of Its Antidepressive Activity

Takashi Hirota,* Keiko Kawanishi, and Kenji Sasaki

*Faculty of Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan

Abstract

A synthesis of D-homo-11,13,15-triazasteroidal skeleton, corresponding to benzo[h]pyrimido[1,2-c]quinazoline as a novel ring system is described. Antidepressive activity of these compounds was screened by inhibitory action of reserpine-induced hypothermia. Compounds VIIc and XVI exhibited antireserpine action.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1131 - 1136
Published online:
DOI: 10.3987/R-1986-04-1131
C-Alkylation, Alkenylation, and Arylation of 1,2,5-Thiadiazoles

Angela De Munno,* Vincenzo Bertini, and Nevio Picci

*Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgnimento 35, I-56126 Pisa, Italy

Abstract

A new synthetic method of 1,2,5-thiadiazoles is reported, which, affording mono- or disubstituted derivatives by one pot procedure, clarifies unknown aspects of the 1,2,5-thiadiazole ring reactivity.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1137 - 1143
Published online:
DOI: 10.3987/R-1986-04-1137
Total Synthesis of (±)-Cerulenin and (±)-Tetrahydrocerulenin

Tomihisa Ohta, Hiroyuki Tsuchiyama, and Shigeo Nozoe*

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

Abstract

Antibiotic (±)-cerulenin and (±)-tetrahydrocerulenin have been synthesized from furfuryl alcohol. The developed procedure involves chemoselective alkylation of furfuryl alcohol and epoxidation of 4-methoxybutenolide.

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Paper | Regular issue | Vol 24, No. 4, 1986, pp. 1145 - 1150
Published online:
DOI: 10.3987/R-1986-04-1145
Base-catalyzed Halogen Dance of 2-Bromotetrathiafulvalene

Juzo Nakayama,* Nagatoshi Toyoda, and Masamatsu Hoshino

*Department of Chemistry, Faculty of Science, Saitama University, Saitama, Saitama 338-8570, Japan

Abstract

Halogenotetrathiafulvalenes were prepared by treating tetrathiafulvalene with lithium diisopropylamide (LDA) and then with halogenating agents. Treatment of 2-bromotetrathiafulvalene with LDA results in the bromine dance which affords tetrathiafulvalene, 2-bromotetrathiafulvalene, three positional isomers of dibromotetrathiafulvalene, and 2,3,6-tribromotetrathiafulvalene.

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45 data found. 31 - 45 listedFirst Previous