Regular Issue

Vol. 26, No. 4, 1987

29 data found. 1 - 29 listed
Communication | Regular issue | Vol 26, No. 4, 1987, pp.863-867
Published online:
DOI: 10.3987/R-1987-04-0863
Cycloaddition Reaction of 1,2,4-Triazolium Phenacylides with Cinnamic Esters

Gheorghe Surpateanu, Alain Lablache-Combier, Pierre Grandclaudon, and Bernard Mouchel

*Laboratoire de Chimie Organique, Faculté de Technologie Chimiqui, Institut Polytechnique de Iasi, Splai Bahlui Stg .71, 6600 Iasi, Romania

Abstract

1,2,4-Triazolium phenacylides generated in situ from the corresponding 1,2,4- triazoliumsalts reacted with cinnamic esters to afford tetrahydropyrroiotriazoie derivatives. These [3+2] dipolar cycloaddition reactions occur stereo- and regiospecific, giving only derivatives of the type (4a-d). The stereo- and regiochemistry of these products was mainly elucidated by 1H-NMR, 13C-NMR and DEPT analysis.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.869-873
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DOI: 10.3987/R-1987-04-0869
Nitrogen Bridgehead Compounds Part 59. Nucleophilic Substitution Reactions of 9-Bromo-6,7,8,9-tetrahydro-4H-pyrido[1,2-a]pyrimidin-4-ones

István Bitter, Gábor Tóth, István Hermecz, and Zoltán Mészáros

*Department of Organic Chemical Technology, Technical University of Budapest, H-1521 Budapest, Gellért tér 4, Hungary

Abstract

Halogen replacement of 9-bromo-6,7,8,9-tetrahydro-4H-pyrido [1,2-a] pyrimidin-4-ones with C-, N-, 0-, and S-nucleophiles can be readily accomplished.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.875-878
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DOI: 10.3987/R-1987-04-0875
A New Route to 4-Oxygenated β-Carbolines: The Total Synthesis of Crenatine

Yasuoki Murakami, Yuusaku Yokoyama, Chiyoko Aoki, Chiemi Miyagi, Toshiko Watanabe, and Taichi Ohmoto

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

Abstract

Crenatine, a new type of β-carboline alkaloid having an oxygen function at its C4-position, was synthesized using ethyl 1-benzylindole-2-carboxylate as a starting material via cyclization of C2-substituent to C3-position of indole nucleus and AlCl3-catalyzed debenzylation for N-protected indoles.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.879-882
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DOI: 10.3987/R-1987-04-0879
Total Synthesis of 7-Hydroxy-"9-oxa"-anthracyclinone and Glycoside Derivatives

Hanh Dufat-Trinh Van, Elisabeth Srguin, François Tillequin, and Michel Koch

*U.A. au C.N.R.S.n°484, Faculté des Sciences Pharmaceutiques et Biologiques, Université René Descartes, 4, Avenue de l’Observatoire, F-75006 Paris, France

Abstract

The racemic title aglycone was prepared in seven steps from quinizarin 5 and its resolution achieved after glycosidation with 3,4-di-O-acetyl-2-deoxy-L-fucose.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.883-884
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DOI: 10.3987/R-1987-04-0883
A Novel Ring Formation of 1,2-Dihydroquinoxalines

Shizuaki Murata, Takashi Sugimoto, and Sadao Matsuura

*Graduate School of Environmental Studies, Nagoya University, Chikusa, Nagoya, Aichi 464-8601, Japan

Abstract

Reaction of O-phenylenediamine with 2,3-epoxyaldehydes gives 2-hydroxyalkyl-1,2-dihydroquinoxalines, while the reaction with 2,3-epoxyesters gives either dihydroquinoxaline derivative or the uncyclized hydroxyamino ester.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.885-894
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DOI: 10.3987/R-1987-04-0885
Chemistry of Penicillin Diazoketones. Part II. from Beta-lactam to Beta-lactone

Hans Ludescher, Ching-Pong Mak, Gerhard Schulz, and Hans Fliri

*Sandoz Forschungsinstitut, 1235 Wien, Brunnerstraße 59, Austria

Abstract

Carbenes formed by transition metal catalyzed decomposition of penicillin-derived diazoketones can undergo different reaction pathways, depending on the presence or absence of the gem-dimethyl group. In the presence of the gem-dimethyl group products are formed via a sulfur ylide intermediate. Bis-nor derivatives undergo Wolff-rearrangement into ketenes which react further to give isopenams. If an hydroxyethyl substituent is present at C-6 of the starting material the original β-lactam is converted into a β-lactone.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.895-898
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DOI: 10.3987/R-1987-04-0895
Total Syntheses of (±)-Agroclavine-I, (±)-6-Nor-chanoclavine-II, and (±)-Chanoclavine-II

Masanori Somei, Fumio Yamada, and Yoshihiko Makita

*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan

Abstract

The first total syntheses of (±)-6-norchanoclavine-II and (±)-chanoclavine-II are achieved. Total synthesis of (±)-agroclavine-I is also reported.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.899-902
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DOI: 10.3987/R-1987-04-0899
Nitriles in Heterocyclic Synthesis: Synthesis of Some New Pyridine, Pyridazine, and Pyrimidine Derivatives

Mona Hassan Mohamed, Nadia Sobhy Ibrahim, and Mohamed Hilmy Elnagdi

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

Abstract

Pyrimidine, pyridazine, pyridine and - pyrazolopyrimidine derivatives were synthesised from 3-amino-2-cyano-4-ethoxycarbonylcrotononitile (1) as a staning material.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.903-907
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DOI: 10.3987/R-1987-04-0903
Nitriles in Heterocyclic Synthesis: Novel Synthesis of Benzo[c]coumarin and of Benzo[c]pyrano[3,2-c]quinoline Derivatives

Ebtisam Abdel Aziz Hafez, Mohamed Hilmy Elnagdi, Abdel Ghani Ali Elagamey, and Fathy Mohamed Abdel Aziz El-Taweel

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

Abstract

Novel syntheses of beneo[c]coumarins and benzo[c]pyrano[3,2-c]quinolines utilizing 3-cyano-4-methylcoumarin and pyrano[3,2-c]quinolin are reported.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.909-912
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DOI: 10.3987/R-1987-04-0909
Preparation of 2,5-Diacylslelnophenes by Condensation of α,α‘-Diketo Selenides with Glyoxal

Juzo Nakayama, Masahiro Shibuya, and Masamatsu Hoshino

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

Abstract

The reaction of selenium oxychloride with 2 equiv. of ketones affords α,α’-diketo selenide dichlorides (1) in excellent yields. Portionwise addition of 1 to a stirred two-phase mixture of an aqueous sodium dithionite solution and benzene gives α,α’- diketo selenides (2) in good yields. The base-catalyzed condensation of 2 with glyoxal provides 2,5-diacylselenophenes (3) in moderate yields.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.913-916
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DOI: 10.3987/R-1987-04-0913
A Facile Synthesis of 4-Mercaptoindoles

Masakatsu Matsumoto and Nobuko Watanabe

*Sagami Central Research Center, 4-4-1 Nishi-Ohnuma, Sagamihara, Kanagawa 229-0012, Japan

Abstract

4-(Ethoxythiocarbonylthio)-1-(p-toluenesulfonyl)indole was synthesized and used as a stable equivalent of 4-mercaptoindoles.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.917-919
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DOI: 10.3987/R-1987-04-0917
Isomerization of N-Acly-1,2,5,6-tetrahydropyridines to N-Acyl-enamines by Palladium on Carbon

Klaus Th. Wanner and Annerose Kärtner

*Institut für Pharmazie und Lebensmittelchemie, Universität München, Sophienstraße 10, D-80333 München, Germany

Abstract

Allylic amides 1 were rearranged to enamides 2 using palladium on carbon as catalyst.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.921-924
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DOI: 10.3987/R-1987-04-0921
Asymmetric α-Amidoalkylation. Synthesis of α-Substituted Piperidines of High Enantiomeric Purity

Klaus Th. Wanner and Annerose Kärtner

*Institut für Pharmazie und Lebensmittelchemie, Universität München, Sophienstraße 10, D-80333 München, Germany

Abstract

A stereoselective α-amidoalkylation was performed employing the chiral and cyclic enamide 1. The resulting amides 6 were employed in the synthesis of the title products.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.925-927
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DOI: 10.3987/R-1987-04-0925
Synthesis of Guaipyridine, Epiguaipyridine, and Related Compounds

Junko Koyama, Teruyo Okatani, Kiyoshi Tagahara, Yukio Suzuta, and Hiroshi Irie

*Kobe Women’s College of Pharmacy, Motoyamakita, Higashinad, Kobe, Hyogo 658, Japan

Abstract

Synthesis of sesquiterpene alkaloids, guaipyridine, epiguaipyridine, and related compounds, was accomplished by application of a method for constructing cycloalkenopyridines by thermal rearrangement of oxime 0-allyl ethers .

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.929-934
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DOI: 10.3987/R-1987-04-0929
Synthesis of Pyrrolidine Derivatives by Improves Aminoselenation via Addition of Boron Trifluoride Complex of Dihomoallylcuprate to Aldimines Containing α-Hydrogen

Makoto Wada, Hideki Aiura, and Kin-ya Akiba

*Department of Chemistry, Faculty of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan

Abstract

Boron trifluoride complex of magnesium dihomoallylcuprate, (CH2=CHCH2CH2)2CuMgBr.BF3, reacted wlth aldimines containing α-hydrogen to afford the corresponding addltion products in good yields. The addition products were converted to pyrrolidine derivatives by treatment with phenylselenenyl chloride in the presence of trifluoroacetic acid and silica gel.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.935-938
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DOI: 10.3987/R-1987-04-0935
Epimedins A, B and C, Flavonoid Glycosides of Epimedium koreanum Herbs

Yoshiteru Oshima, Maki Okamoto, and Hiroshi Hikino

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

Abstract

Three new flavonoid glycosides, epimedins A, B and C, have been isolated from Epimedium koreanum herbs, the structures of which have been elucidated on the basis of chemical and spectroscopic data as shown in fomulas I, II and III, respectively

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.939-942
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DOI: 10.3987/R-1987-04-0939
Preparation of α-Quinque- and α-Septithiophenes and Their Positional Isomers

Juzo Nakayama, Yoichi Nakamura, Shigeru Murabayashi, and Masamatsu Hoshino

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

Abstract

α-Quinque- and α-septithiophenes were synthesized in four steps starting from α-bi- and α-terthiophenes, respectively. One of positional isomers of each oligothiophene described above is also synthesized.

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Communication | Regular issue | Vol 26, No. 4, 1987, pp.943-946
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DOI: 10.3987/R-1987-04-0943
Thalocsessine, a New C20-Diterpenoid Alkaloid from Thalictrum sessile Hayata

Yang-Chang Wu, Tian-Shung Wu, Masataka Niwa, Sheng-Teh Lu, and Yoshimasa Hirata

*Faculty of Pharmacy, Meijo University, 150 Yagoto, Tempaku-ku, Nagoya, Aichi 468-8503, Japan

Abstract

The structure of thalicsessine, a new C20-diterpenoid alkaloid isolated from Thalictrum sessile Hayata (Ranunculaceae), together with a known diterpenoid alkaloid spiradine A, was elucidated on the basis of spectral and chemical evidence. This is the first report on diterpenoid alkaloids obtained from the plant of the genus Thalictrum.

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.947-960
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DOI: 10.3987/R-1987-04-0947
Two Acyclic Analogues of 2-β-D-Ribofuranosylthiazole-4-carboxamide (Tiazofurin)

Lajos Kovács, Pál Herczegh, Gyula Batta, and István Farkas

*Department of Organic Chemistry, Lajos Kossuth University, P.O.Box 20, H-4010 Debrecen, Hungary

Abstract

Two different synthetic strategies have been elaborated for the synthesis of 2-[(2-hydroxyethoxy)methyl] thiazole-4-carboxamide (4) and 2-{[2-hydroxy-1-(hydroxymethyl) ethoxy]methyl}thiazole-4-carboxamide (5).

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.961-968
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DOI: 10.3987/R-1987-04-0961
Molecular Structure and Stability of Isoxazolium Enolates

Gury Zvilichovsky and Mordechai David

*Department of Medicinal Chemistry, The Hebrew University, P.O. Box 12065, Jerusalem 91120, Israel

Abstract

Single crystal X-ray diffraction analysis, spontaneous formation and solvolytic stability of the dipolar Schiff base isoxazolium enolate, derived from aldehydes and ketones were studied. The cross conjugated betaine (V) derived from 2,4-dimethoxybenzaldehyde by condensation with 4-phenyl disic acid (II), showed coplanarity and cis configuration. The X-ray results revealed exceptionally long bonds between the two units, that of the anion and that of the cation. Results obtained by omega beta calculations were in line with the experimental observations. Cyclopentanone was the only ketone that gave a stable dipolar condensation product. Derivatives of aromatic aldehydes are generally more stable probably for the reason the coplanarity of the cationic part of the molecule is more feasible. There is evidence for attractive C-H..0 interactions which might contribute to stability in aldehyde derivatives (IIIa). Ketisates (IIlb), which were synthesized by an alternative route were found to hydrolyze spontaneously when dissolved in moist solvents. Analogous betaines that have N1-substituted pyrazole instead of isoxazole were also studied, leading to a scheme for facile decomposition of oximes and hydrazones.

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.969-988
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DOI: 10.3987/R-1987-04-0969
Interaction of Thietes with Electron-deficient Molecules

Sharon Marinuzzi-Brosemer, Bhalchandra H. Patwardhan, Kenneth A. Greenberg, and Donald C. Dittmer

*Department of Chemistry, Syracuse University, Syracuse, New York 13244-1200, U.S.A.

Abstract

Thietes (thiacyclobutenes) give substituted 1,4-benzodioxanes when treated with the o-quinones, o-chloranil and o-bromanil, but dehydrogenation occurs vith the p-quinane, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), as indicated by the formation of the hydroquinone in good yield. Colored solutions are formed when thietes are mixed with the electron acceptors DDQ, tetracyanoethylene (TCNE) and tetracyanoquinodimethane (TCNQ). The stoichiometry of the charge transfer complexes appears to be 1:1 (donor:acceptor) according to Job plots. Formation constants do not vary greatly from complex to complex. Blue-black solids have been obtained from thietes and TCNQ. The material obtained from 2H-thiete is electrically conducting - a semiconductor - but that from 3-phenyl-2H-thiete is an insulator. Several of the isolated charge-transfer complexes give satisfactory elemental analyses for 1:1 complexes and most of them give broad electron spin resonance spectra.

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.989-1000
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DOI: 10.3987/R-1987-04-0989
Proton-ionizable Macrocycles Containing 1,2,4-Triazole and 4-Amino-1,2,4-triazole Subunits

José M. Alonso, M. Rosario Martín, Javier de Mendoza, Tomás Torres, and José Elguero

*Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049-Madrid, Spain

Abstract

Macrocycles 2a and 2b, containing a proton-ionizable 1,2,4-triazole subcyclic unit, havebeen obtained from the appropriate 3,5-disubstituted N-amino-1,2,4-triazoles and tetraethyleneglycol derivatives. The N-amino function was used as a protective group in the macrocyclization step. The method allowed the preparation of the chiral macrocycle 2b in three steps, from S-lactic acid, in high optical purity and an overall yield of 16%. Triazolyl lone pairs of the macrocycles 2a and 2b, and of their N-aminated precursors 1a and 1b, participate in the complexation of Eu(fod)3 and Pr(fod)3, as well as the crown ether moieties, but not N-amino groups which, when present, were found to be inside the cavity. Ion transport rates towards alkali-metal ions through a bulky chloroform phase were low and showed little selectivity.

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.1001-1013
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DOI: 10.3987/R-1987-04-1001
Chemistry of Penicillin Diazoketones. Part III. Transformation of Tricyclic Beta-lactams

Ching-Pong Mak, Gerhard Schulz, and Hans Fliri

*Sandoz Forschungsinstitut, 1235 Wien, Brunnerstraße 59, Austria

Abstract

The transformation of tricyclic beta-lactams 1a-c, which are obtained from the corresponding penicillin diazoketones, into carbapenams 7-11 are described. Whereas reduction of 1c with tetra-n-butylammonium borohydride gave cleanly the hydmxy-lactam 3c, the isomeric ketone 1b yielded 3c, together with two tricyclic lactones 5a/b Azido-lactones 5c/d were obtained similarly when we reacted 1b with aluminium chloride/sodium azide. The structural assignment of these novel compounds was based mainly on spectroscopic analysis and comparison with the corresponding tricyclic lactam 3c.

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.1015-1028
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DOI: 10.3987/R-1987-04-1015
Cyclization of C- and O-Acyl Derivatives of p-Toluamide O-Acetoacetyloxime

Etsuko Kawashima, Yuko Ando, Katsumi Tabei, and Hiroshi Miyamae

*Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan

Abstract

Reaction of p-toluamide 0-acetoacetyloxime (1) with acyl chloride (2) in the presence of basic catalyst gave the corresponding 0- and C-acyl derivatives (3 and 4). Cyclization of 3 afforded 5-(2-acyloxypropeny1)-3-(p-toly1)-1,2,4-oxadiazole derivatives (6) and 5-acetonyl-3-(p-toly1)-1,2,4-oxadiazole (7). Cyclization of 4 gave 5-(1-acyl-2- oxopropy1)-1,2,4-oxadiazole derivatives (8), 4-[ 1-amino-1 - (p-tolyl)]methylene-3-methyl-2-isoxazolin-5-one (9) and 5-substituted 3-(p-to1yl)-1,2,4-oxadiazole derivatives (10).

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.1029-1036
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DOI: 10.3987/R-1987-04-1029
The Preparation of Pyrido[4,3,2-de]quinazoline and Pyrido[3,4,5-de]quinazoline

Paul D. Woodgate, John M. Herbert, and William A. Denny

*Department of Chemistry, University of Auckland, Private Bag 92019, Auckland, New Zealand

Abstract

The preparation of the novel ring systems, pyrido[4,3,2-de]quinazoline and pyrido[3,4,5-de]quinazoline, from quinoline and isoquinoline respectively, is described.

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.1037-1041
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DOI: 10.3987/R-1987-04-1037
Formation of peri-Fused Heterocycles by Intramolecular Displacement of Halide

John M. Herbert, Paul D. Woodgate, and William A. Denny

*Department of Chemistry, University of Auckland, Private Bag 92019, Auckland, New Zealand

Abstract

The preparation of phthaloperin-12-one and naphtho[l,8-de]-1,3-thiazine using copper-assisted displacement of aryl halogen is described.

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Paper | Regular issue | Vol 26, No. 4, 1987, pp.1043-1050
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DOI: 10.3987/R-1987-04-1043
Behaviour of Some Perimidines towards Oxidants

John M. Herbert, Paul D. Woodgate, and William A. Denny

*Department of Chemistry, University of Auckland, Private Bag 92019, Auckland, New Zealand

Abstract

The oxidation of some perimidines with 3-chloroperbenzoic acid, trifluoroperacetic acid, and dipotassium nitrosodisulphonate is reported. Perimidine-2-thione is oxidised to perimidine-2-sulphonic acid, while other perimidines are oxidised to give 4-and 6-perimidinones.

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Review | Regular issue | Vol 26, No. 4, 1987, pp.1051-1076
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DOI: 10.3987/R-1987-04-1051
Chlorosulfonyl Isocyanate: A Novel Reagent for the Synthesis of Heterocycles

Ahmed Kamal and Pralhad B. Sattur

*Medical Chemistry & natural Products Division, Regional Research Laboratory, Hyaderabad 500 007, India

Abstract

Chlorosulfonyl isocyanate, a novel reagent employed towards the synthesis of heterocycles and related compounds, finds extensive use. An effort has been made in this review to catalogue and update its applications for the synthesis of nitrogen, oxygen and sulphur containing ring systems.

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Review | Regular issue | Vol 26, No. 4, 1987, pp.1077-1097
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DOI: 10.3987/R-1987-04-1077
Azlactones: Retrospect and Prospect

Arya K. Mukerjee

*Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi - 221005, India

Abstract

Interest in the chemistry of azlactones continues unabated because of their usefulness as intermediates in the synthesis of diverse products. The present review attempts to present the prolific development of recent years in this area and gives a critical and unified account of azlactones under the following headings:

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29 data found. 1 - 29 listed