Regular Issue

Vol. 34, No. 9, 1992

18 data found. 1 - 18 listed
Communication | Regular issue | Vol 34, No. 9, 1992, pp. 1691 - 1696
Published online:
DOI: 10.3987/COM-92-6077
Thermal Dimerization of Noracronycine

Geneviève Baudouin, Sofia Mitaku, Emmanuel Mikros, Alexios-Léandors Skaltsounis, and François Tillequin*

*Laboratoire de Pharmacognosie de l’Université René Descartes, U.R.A. au C.N.R.S. n°1310, Faculté des Sciences Pharmaceutiques et Biologiques, 4 Avenue de l’Observatoire, F-75006 Paris, France


Thermal dimerization of the acridone alkaloid noracronycine (2) leads to Diels-Alder adducts (3) and (4), possessing a rearranged structure.

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Communication | Regular issue | Vol 34, No. 9, 1992, pp. 1697 - 1702
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DOI: 10.3987/COM-92-6082
Synthesis of Halogenated Oligo-N-methylpyrrolecarboxamide Derivatives and Their Photochemical DNA Cleaving Activities

Toyomi Matsumoto, Yuko Utsumi, Yasuhiro Sakai, Kouhei Toyooka, and Masayuki Shibuya*

*Faculty of Pharmaceutical Sciences, University of Tokushima, Sho-machi 1, Tokushima 770, Japan


Synthesis of various halogenated oligo-N-methylpyrrolecarboxamide derivatives and their DNA cleaving activities under UV-A irradiation were described.

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Communication | Regular issue | Vol 34, No. 9, 1992, pp. 1703 - 1706
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DOI: 10.3987/COM-92-6083
A Site- and Regio-specific Route to Perfluoroalkylisoxazoles

Pierfrancesco Bravo, Dario Diliddo, and Giuseppe Resnati*

*C.N.R.-Centro Studio Sostanze Organiche Naturali and Dipartimento Chimica , Politecnico, Piazza Leonardo da Vinci 32, 20133 Milano, Italy


The 1,3-cycloaddition reaction of nitrile oxides (1) to β-perfluoroalkyl-β-dicarbonyl compounds (2) affords regio- and site-selectively either 5-perfluoroalkylisoxazoles (4) or 4-trifluoroacetylisoxazoles (6) according to the nature of dipolarophiles (2).

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Communication | Regular issue | Vol 34, No. 9, 1992, pp. 1707 - 1710
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DOI: 10.3987/COM-92-6110
Cycloaddition Reaction of 4-Oxo-4H-pyrazole 1,2-Dioxides with Epoxynaphthalene. X-Ray Analysis of the Cycloadduct and Some Comments on Cycloaddition Behavior

Kazunobu Harano, Yasuyuki Yoshitake, Masashi Eto, and Takuzo Hisano*

*Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-hon-machi, Kumamoto 862, Japan


The crystal structure of the cycloadduct of 2,5-bis(methoxycarbonyl)-4-exo-4H-pyrazole 1,2-dioxide with epoxynaphthalene was elucidated. The result indicates that the cycloadduct resulted from the direct 1,3-dipolar cycloaddition.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1711 - 1720
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DOI: 10.3987/COM-92-6058
Fused 1,2,4-Triazole Heterocycles. I. Synthesis of Novel [1,2,4]Triazolo[5’,1’:2,3][1,3]thiazino[6,5-b]quinolines.

Ferenc Kóródi,* Zoltán Cziáky, and Zoltán Szabó

*Alkaloida Chemical Company Ltd., H-4440 Tiszavasvári, Hungary


Derivatives of a new heterocyclic ring system of [1,2,4]triazolo[5’,1’:2,3][1,3]thiazino[6,5-b]quinolines (4, 5, 6, 7 and 8) have been synthesised by the reaction of 2-chloroquinoline-3-carbaldehyde derivatives (1 and 2) with 1,2,4-triazole-5-thiols (3), and subsequent transformations of the hydroxy group of 11-hydroxy[1,2,4]triazolo[5’,1’:2,3][1,3]thiazino[6,5-b]quinoline (4a).

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1721 - 1728
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DOI: 10.3987/COM-92-6059
Synthesis of Pyridine-2(1H)-thione and Thieno[2,3-b]pyridine Derivatives

Galal E. H. Elgemeie,* Ibrahim S. Alnaimi, and Hafsa F. Alarab

*Chemistry Department, Faculty of Science, Qatar University, Doha, State of Qatar


A synthesis of pyridine-2(1H)-thiones and thieno[2,3-b]pyridines utilizing cyanothioacetamide and 2-arylhydrazono-1,3-diphenylpropane-1,3-diones as starting components is described.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1729 - 1736
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DOI: 10.3987/COM-92-6061
The Synthesis of Fluorine-containing Aza-macrocyclic Compounds

Zhan-Ting Li, Yong-Da Lin, and Ching-Sung Chi*

*Shanghai Institute of Organic Chemistry, Academia Sinica, 345 Lingling Road, Shanghai 200032, China


Four aza-macrocyclic compounds were synthesized by reactions of phthalaldehydes and phthaloyl chlorides with N,N’-di(2-aminomethyl-3-fluorophenyl)ethylenediamine (8) and their structures were identified. The nucleophilic substitution reaction of 2,6-difluorobenzonitrile (1) was discussed.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1737 - 1748
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DOI: 10.3987/COM-92-6067
Synthesis of Selenopsilocine (3-Dimethylaminoethyl-4-hydroxybenzo[b]selenophene)

Abdelmjid Dari, Léon E. Christiaens, and Marcel J. Renson*

*Heterocyclic Chemistry, Institute of Organic Chemistry, B.6., University of Liège, Sart-Tilman, 4000 LIEGE, Belgium


Starting from the known 6-methoxyanthranilic acid (5), we have synthesized in six steps the selenium analogue of psilocine (1c). The key intermediate is the 4-methoxyselenoindoxyl (8), which is condensed with the dimethylaminocarbamoylmethylenetriphenylphosphorane to give the aromatic amide (9a). Its reduction with lithium aluminium hydride leads to the methoxyamine (9b) which is finally demethylated by sodium ethanethiolate to 1c.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1749 - 1758
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DOI: 10.3987/COM-92-6070
General Synthesis of 2,3-Substituted 5-Membered Heterocyclic Quinones

Mahmoud Cherif, Philippe Cotelle,* and Jean-Pierre Catteau

*Laboratoire de Chimie Organique Physique, URA CNRS 351, U. S. T. Lille, Villeneuve d’ Ascq, France


4,7-Dimethoxybenzo[b]furan, -thiophene, -selenophene and 4,7-dimethoxyindole have been prepared by a two-step procedure involving a cyclization-dehydration of the acetals (1). The oxidative demethylation of 4,7-dimethoxybenzo[b]thiophene, -selenophene and 4,7-dimethoxyindole afforded the corresponding quinones whereas 4,7-dimethoxybenzo[b]furan gave 5,5’-bisbenzo[b]furan-1,4-dionyl (4b).

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1759 - 1771
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DOI: 10.3987/COM-92-6085
The Synthesis of Pyrrolo[1,2-a]pyrazin-1(2H)-ones and Pyrrolo[1,2-b]pyridazin-6(5H)-ones

Derek McHattie,* Robert Buchan, Martin Fraser, and Paul V. S. Kong Thoo Lin

*Department of Applied Science, The Robert Gordon Institute of Technology, St Andrew’s Street, Aberdeen AB1 1HG, Scotland


The pyrrolo[1,2-a]pyrazin-1(2H)-ones (10), (11), (12) and (13) and the pyrrolo[1,2-b]pyridazin-6(5H)-one (18) were prepared either a) directly by Chichibabin quaternisation-cyclisation of the corresponding methoxymethylpyrazine or pyridazine or b) by hydrogen halide hydrolysis of methoxypyrrolo[1,2-a]pyrazines and methoxypyrrolo[1,2-b]pyridazines. Protonation studies and some reactivity of the systems are discussed.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1773 - 1782
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DOI: 10.3987/COM-92-6086
A New Short Synthesis of (±)-Eburnamonine

Esko Karvinen and Mauri Lounasmaa*

*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, SF-02150 Espoo, Finland


A new short synthesis of the indole alkaloid eburnamonine (1), starting from the easily available enamine (3) (1,12b-didehydroindolo[2,3-a]quinolizidine) is described. Pentacyclic lactam (7) (18-nor-19-ethoxycarbonyl-21-epieburnamonine) (trans D/E ring juncture), the key intermediate in this synthesis, was prepared from enamine (3) by dialkylating with ethyl iodoacetate in the presence of diisopropylethylamine (DIPEA). LiAlH4-reduction of lactam (7) gave a 2:1 mixture of compounds (10a) (21-epi-18-hydroxyeburnamine) and (10b) (16-epi-21-epi-18-hydroxyeburnamine). Wolff-Kishner reduction of the "masked" carbonyl group present at C(16) of compounds (10a) and (10b) gave the alcohol (14) (1-ethyl-1-(2-hydroxyethyl)indolo[2,3-a]quinolizidine) possessing the natural cis-relationship between C(21)-hydrogen and C(20)-ethyl group. PCC oxidation of alcohol (14), followed by cyclization, completed the synthesis of (±)-eburnamonine (1).

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1783 - 1801
Published online:
DOI: 10.3987/COM-92-6089
Photocyclization of Enamides. 37. Synthesis of Despyrrolo Analogues of Reserpine Demonstrating a Versatile Addition-Elimination Reaction Strategy for the Preparation of Functionalized Reserpine Ring System

Takeaki Naito,* Etsuko Kuroda, Okiko Miyata, and Ichiya Ninomiya

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


Despyrrolo analogues (25) and (26) of reserpine and were prepared via the routes involving reductive photocyclization of the enamide (4) and addition-elimination reaction of the resulting β-methoxy enones (7) and (8).

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1803 - 1812
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DOI: 10.3987/COM-92-6090
A Convenient Synthesis of 3-Hydroxy-4H-pyran-4-one Derivatives Having a Halo or Hydroxy Group at the 5-Position

Hisashi Takao,* Yoshinori Endo, and Tokunaru Horie

*Naruto Research Center, Otsuka Chemical Company, Satoura, Naruto, 772, Japan


The reaction of 4,5-epoxy-4-halo-6-methoxy-2-methyltetrahydropyran-3-ones (4b and 5b) in acidic media was examined and the following results were found: The reaction of 4b or 5b with 1% sulfuric acid afforded a mixture of 3,5-dihydroxy-4H-pyran-4-one (1b) and 5-halo-3-hydroxy-4H-pyran-4-one (2b or 3b), but the use of concentrated acid formed the corresponding 5-halo-4H-pyran-4-one (2b or 3b) only. The reaction was applicable for a general method for synthesizing 3,5-disubstituted 4H-pyran-4-ones (1, 2, and 3).

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1813 - 1828
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DOI: 10.3987/COM-92-6099
Five New Isoprenoid-substituted Flavonoids, Glyasperins F, G, H, I, and J from the Roots of Glycyrrhiza aspera

Lu Zeng, Toshio Fukai, Taro Nomura,* Ru-Yi Zhang, and Zhi-Cen Lou

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


Five new isoprenoid-substituted flavonoids, glyasperins F (1), G (2), H (3), I (4), and J (5) were isolated from the roots of Glycyrrhiza aspera. The structures of glyasperins F-J were elucidated by spectroscopic methods.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1829 - 1833
Published online:
DOI: 10.3987/COM-92-6106
1H and 13C Chemical Shift Data of Some Ommochrome Models: Substituted Benzo[3,2-a]-5H-phenoxazin-5-one

Adele Bolognese and Michelangelo Parrilli*

*Dipartimento di Chimica Organica e Biologica, Università di Napoli "Federico II", via Mezzocannone 16, 80134 Napoli,Italy


1H and 13C chemical shift data are reported for some substituted benzo[3,2-a]-5H-phenoxazin-5-ones, that are convenient models of natural ommochromes. Assignments are based on one- and two-dimensional techniques.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1835 - 1845
Published online:
DOI: 10.3987/COM-92-6113
Naturally Occurring Naphthazarins. Synthesis of (±)-Ventiloquinones C, D, E and G

Daniel Bergeron and Paul Brassard*

*Département de Chimie, Université Laval, Québec(Québec), Canada G1K 7P4


The title compounds have been synthesized, some for the first time, from previously obtained (±)-1,3-dimethyl-10-hydroxybenzisochroman-6,9-quinones, by oxidation of the corresponding hydroquinone dimethyl ethers using ceric ammonium nitrate or better [bis(trifluoroacetoxy)iodo]benzene and, as required, selective demethylation.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1847 - 1856
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DOI: 10.3987/COM-92-6114
Synthesis of OPC-15161

Hao Jing, Kazunori Murakami, Yutaka Aoyagi, and Akihiro Ohta*

*Tokyo College of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-03, Japan


OPC-15161 (1), an inhibitor of superoxide anion generation by guinea pig macrophages, was synthesized from 5-chloro-3-isobutyl-6-methylpyrazine in several steps.

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Paper | Regular issue | Vol 34, No. 9, 1992, pp. 1857 - 1870
Published online:
DOI: 10.3987/COM-92-6123
Quinolizidines. XXXI. A Synthesis of the Dibenzo[a,h]quinolizidine Ring System: An Application of the Mercuric Acetate-Edetic Acid Oxidation Method to 1,2,3,4-Tetrahydroisoquinoline

Masashi Ohba, Yoko Shinbo, Takako Ohashi, Mitsuhiro Toda, and Tozo Fujii*

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


A formal synthesis of 2,3-dimethoxydibenzo[a,h]quinolizidine (25a) has been achieved through a route including mercuric acetate-edetic acid oxidation of a benzene-fused piperidine. The route started with an initial condensation of 1,2,3,4-tetrahydroisoquinoline (3a) with 3,4-dimethoxyphenacyl bromide (7) and proceeded through the amino ketone (8a), amino alcohol (9a), lactam alcohol (10a), and the lactam (15a). A parallel sequence of reactions starting with 1,2,3,4-tetrahydro-6,7-dimethoxyisoquinoline (3b) and 7 concluded a formal synthesis of the 2,3,11,12-tetramethoxy analogue (25b) of the tetracycle (25a). In the mercuric acetate-edetic acid oxidations of the amino alcohols (9a,b) under acidic or alkaline conditions, the oxazoloisoquinoline derivatives (11a,b) were obtained besides the desired lactam alcohols (10a,b).

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18 data found. 1 - 18 listed