Regular Issue

Vol. 34, No. 3, 1992

18 data found. 1 - 18 listed
Communication | Regular issue | Vol 34, No. 3, 1992, pp.425-428
Published online:
DOI: 10.3987/COM-91-5869
Phase Transfer Catalysed Oxidative Arylthiolation of 1,3,6-Trimethyluracil and Its 5-Bromo Derivative

Subodh Kumar,* Swapandeep S. Chimni, and Deepika Cannoo

*Department of Chemistry, Guru Nanak Dev University, Amritsar -143 005, Punjab, India

Abstract

Reaction of 1,3,6-trimethyluracil and its 5-bromo derivative with arylthiols under phase transfer catalytic conditions provides C-H substitution products, 5-arylthio-1,3,6-trimethyluracils and 5-arylthio-6-arylthiomethyl-1,3-dimethyluracils.

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Communication | Regular issue | Vol 34, No. 3, 1992, pp.429-434
Published online:
DOI: 10.3987/COM-91-5936
A Convenient, One-Pot Synthesis of Azulenes Having Versatile Functional Groups by the Reaction of 2H-Cyclohepta[b]furan-2-ones with Furan Derivatives

Hidetsugu Wakabayashi,* Paw-Wang Yang,* Chi-Phi Wu, Kimio Shindo, Sumio Ishikawa, and Tetsuo Nozoe

*Department of Chemistry, Faculty of Science, Josai University, 1-1 Keyakidai, Sakado-shi, Saitama 350-02, Japan

Abstract

2-Acylmethyl- and 2-methoxycarbonylmethylazulene derivatives having versatile functional groups in the side chain, are synthesized in one-pot by the reaction of 2H-cyclohepta[b]furan-2-ones with furans on heating at 160 - 190 °C in aprotic solvent.

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Communication | Regular issue | Vol 34, No. 3, 1992, pp.435-440
Published online:
DOI: 10.3987/COM-91-5940
Electrophilic Olefin Heterocyclization in Organic Synthesis. Formation of δ-Lactams by Iodine-induced Lactamization of δ,ε-Unsaturated Thioimidates

Hiroki Takahata,* Eng-Chi Wang, Kazumi Ikuro, Takao Yamazaki, and Tekefumi Momose*

*Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-01, Japan

Abstract

The diastereoselective iodine-induced lactamization of δ,ε-unsaturated thioimidates (1) accessible from allylation of a dianion of N-benzyl-3-phenylsulfonylpropionamide (3) followed by elaboration gave the substituted δ-lactams (2).

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Communication | Regular issue | Vol 34, No. 3, 1992, pp.441-444
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DOI: 10.3987/COM-91-5949
Alkaloids of Aconitum balfourii Stapf.

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

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

Abstract

Three new norditerpenoid alkaloids, 8-O-methylveratroylpseudaconine (9), veratroylbikhaconine (10), and balfourine (11), have been isolated from Aconitum balfourii, together with eight known alkaloids, pseudaconitine, veratroylpseudaconine, indaconitine, ludaconitine, 8-deacetylyunaconitine, bikhaconitine, neoline, and chasmanine. The new structures were derived from physical and spectroscopic data and chemical correlations with alkaloids of established structures.

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Communication | Regular issue | Vol 34, No. 3, 1992, pp.445-448
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DOI: 10.3987/COM-91-5950
Novel Neuroexcitatory Amino Acid from Clitocybe acromelalga

Kimiaki Yamano, Kimiko Hashimoto, Haruhisa Shirahama*

*Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060, Japan

Abstract

Novel neuroexcitatory amino acid, L-3-(6-carboxy-2-oxo-4-pyridyl)alanine (1), was isolated from the poisonous mushroom, Clitocybe acromelalga, and its structure was deduced by spectral data and biogenesis and confirmed by the chemical conversion.

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Communication | Regular issue | Vol 34, No. 3, 1992, pp.449-456
Published online:
DOI: 10.3987/COM-91-5955
Conformational Analysis of 2-Aryl-4-piperidones. Effect of the Indole Protective Phenylsulfonyl Group

Mario Rubiralta,* Javier Luque, Modesto Orozco, Anna Diez, and Isabel López

*Laboratory of Organic Chemistry, Faculty of Pharmacy, University of Barcelona, 08028 Barcelona, Spain

Abstract

A spectroscopic and theoretical study on 2-arylpiperidines, which shows a rare stabilization in an axial disposition of the aryl substituent in the particular cases of 2-[1-(phenylsulfonyl)-2-indolyl]-4-piperidones (11) and (12), is reported.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.457-464
Published online:
DOI: 10.3987/COM-91-5840
Studies on 2-Substituted Methylazoles: Novel Synthesis of 6-(N-Piperidinyl) and 6-(N-Morpholinyl)-1,4-dihydropyridine Derivatives Incorporating Benzimidazole Moiety with Anticipated Biological Activity

Galal A. M. Nawwar,* Hussein F. Zohdi, Randa H. Swellem, and Soad A. Osman

*National Research Center, Dokki, Cairo, Egypt

Abstract

The reaction of 2-(2-benzimidazolyl)acetonitrile with 3-(2-hydroxyaryl)propenones (2) in the presence of three equivalents of bases afforded the titled ring systems. When 2-(2-benzothiazolyl)acetonitrile was used instead of 2-(2-benzimidazolyl)acetonitrile the reaction afforded the 2-(benzopyran-3-yl)benzothiazole (9).

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.465-478
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DOI: 10.3987/COM-91-5887
The Synthesis of Oxoaporphines and Phenanthrenediones from 7-Hydroxydehydronoraporphines

Carl Costanza, George R. Lenz,* and Ralph A. Lessor

*The BOC Group Technical Center, Health Care Research and Development, 100 Mountain Avenue, Murray Hill, New Jersey 07974, U.S.A.

Abstract

Oxidation of 7-hydroxydehydronoraporphines with air over platinum or palladium yields oxoaporphines in high yield. When the nitrogen is acylated, oxidation with air in the presence of copper ions causes an oxidative ring fragmentation to form phenanthrenediones, also in high yield.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.479-482
Published online:
DOI: 10.3987/COM-91-5909
Xanthone Constituents of Hypericum inodorum

Luz Cardona, Isabel Fernández, and José R. Pedro*

*Department of Organic Chemistry, Faculty of Chemistry, Valencia University, 46100-Burjassot, Valencia, Spain

Abstract

The isolation and identification of six xanthones from the aerial parts of Hypericum inodorum are reported. One of these compounds, 5-hydroxy-2-methoxyxanthone, is described for the first time.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.483-495
Published online:
DOI: 10.3987/COM-91-5912
Stereospecific Synthesis of trans, cis-1,3,4-Trisubstituted 1,2,3,4-Tetrahydro-β-Carbolines

Mohammad Behforouz,* Sarah J. West, Chitra Chakrabarty, David A. Rusk, and Hamideh Zarrinmayeh

*Department of Chemistry, Ball State University, Muncie, IN 47306, U.S.A.

Abstract

Pictet-Spengler condensation of Nb-benzyl-β-methyltryptophan methyl ester (2RS, 3SR;4) with aldehydes followed by debenzylation afforded trans, cis-1,3,4-trisubstituted 1,2,3,4-tetrahydro-β-carbolines in complete stereospecific fashion. Tetrahydro-β-carbolines (6a) and (6b) were prepared by the direct condensation of β-methyltryptophan methyl ester (4) with the corresponding aldehydes. The stereochemistry of the products was confirmed by an X-ray analysis of 6a.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.497-504
Published online:
DOI: 10.3987/COM-91-5916
Regioselective Cycloadditions of 1H-Azepine and 1H-1,2-Diazepine Derivatives with N,α-Diphenylnitrone and Nitrosobenzene

Katsuhiro Saito,* Akihiro Yoshino, Hiroyuki Watanabe, and Kensuke Takahashi

*Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466, Japan

Abstract

Reactions of 1-carbomethoxy-1H-azepine with N,α-diphenylnitrone afforded endo- and exo-[2+3]-type cycloadducts in almost the same ratio. Reactions of 1-carboethoxy-1H-azepine with nitrosobenzene in chloroform afforded [4+2]- and [6+2]-types of cycloadducts. Analogous results were obtained in the reactions using 1-carboethoxy-1H-1,2-diazepine.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.505-516
Published online:
DOI: 10.3987/COM-91-5918
Synthesis of 4',5- and 3',4',5-Oxygenated Pyranoisoflavones: Alpinumisoflavone and Related Compounds, and a Revised Structure of Derrone

Masao Tsukayama,* Yasuhiko Kawamura, and Hideo Tahara

*Department of Chemical Science and Technology, Faculty of Engineering, The University of Tokushima, Minamijosanjima-cho, Tokushima 770, Japan

Abstract

Alpinumisoflavone (4',5-dihydroxy-2",2"-dimethylpyrano[5",6"-g]isoflavone) (1a) was synthesized by regioselective reduction of 7-(4-hydroxyphenyl)-2,3-dihydro-5-methoxy-2,2-dimethyl-4H,6H-benzo[1,2-b:5,4-b']dipyran-4,6-dione (15a) with NaBH4 and dehydration of the resultant alcohol, followed by demethylation with BCl3. Its angular isomer (4',5-dihydroxy-2",2"-dimethylpyrano[6",5"-h]isoflavone) (2a) was synthesized from 3-(4-hydroxyphenyl)-8,9-dihydro-5-tosyloxy-8,8-dimethyl-4H,10H-benzo[1,2-b:3,4-b']dipyran-4,10-dione (27a) in a similar manner.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.517-547
Published online:
DOI: 10.3987/COM-91-5927
Stereospecificity in the Pictet-Spengler Reaction. Enantiospecific Synthesis of (6S,10S)-(-)-5-Methyl-9-oxo-12-benzyl-6,7,8,9,10,11-hexahydro-6,10-imino-5H-cyclooct[b]indole, a Template for Preparation of Macroline/Sarpagine Alkaloids

Lin-Hua Zhang, Ying-Zhi Bi, Fu-Xiang Yu, Gerald Menzia, and James M. Cook*

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

Abstract

The Synthesis [from D(+)-tryptophan] of the tetracyclic ketone [(-)-1b] was carried out in enantiospecific fashion (>98% ee) via the 1,3-transfer of chirality from Na-methyl, Nb-benzyl tryptophan methyl ester [(+)-14] to the trans diastereomer [(-)-4b] in the Pictet-Spengler reaction. Although the condensation of 14 with aldehyde (15) in refluxing benzene generated the tetrahydro β-carbolines (4b/5b) in a kinetic ratio (72:28), epimerization (C-1) of the cis diastereomer [(+)-5b] into the trans isomer [(-)-4b] occurred stereospecifically under acidic conditions. Dieckmann cyclization of either the Na-methyl, Nb-benzyl-cis-(+)-5b or trans-(-)-4b diastereomer provided the cis-bicyclo[3.3.1]azanonane system at approximately the same rate, although the β-keto esters were antipodal, in contrast to results reported in the Na-benzyl series by Magnus.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.549-559
Published online:
DOI: 10.3987/COM-91-5944
Diorganotin Derivatives of 2,6-Dihydroxymethylpyridine and of 3-(N-Pyrrolidino)-1,2-propanediol: Synthesis, Characterization and in vitro Antitumor Activity

Marcel Gielen,* Mohammed Bouâlam, Monique Biesemans, Bernard Mahieu, and Rudolph Willem

*Free University of Brussels, Departement of General and Organic Chemistry, Faculty of Engineering, Room 8G512, Pleinlaan 2, B-1050 Brussels, Belgium

Abstract

Three diorganotin(IV) derivatives of 2,6-dihydroxymethylpyridine and 3-(N-pyrrolidino)-1,2-propanediol have been synthesized and characterized by Mössbauer spectroscopy, mass spectrometry and by 1H, 13C and 119Sn nmr. Their activities in vitro against two human tumor cell lines, MCF-7 and WiDr, are compared to those of cis-platin and doxorubicin.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.561-568
Published online:
DOI: 10.3987/COM-91-5945
Synthesis of 4-Alkoxyquinolines from Quinoline Reissert Compounds

Michiharu Sugiura,* Yoshie Sakurai, and Yoshiki Hamada

*Faculty of Pharmacy, Meijo University, Yagotoyama, Tempaku-ku, Nagoya 468, Japan

Abstract

The quinoline Reissert compound (5a) was converted to 1-benzoyl-3-bromo-2-cyano-1,2,3,4-tetrahydro-4-methoxyquinoline (6a) by successive treatment in methanol with bromine and aq. sodium carbonate. Hydrolysis of 6a with hydrochrolic acid gave 3-bromoquinoline (4; R=H), but that with aq. sodium hydroxide afforded 4-methoxyquinoline (7a). Reissert compounds derived from some quinoline derivatives (5) gave the corresponding 4-methoxyquinolines (7) through tetrahydroquinolines (6) in a similar way.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.569-574
Published online:
DOI: 10.3987/COM-91-5946
C-Nucleosides. 17. A Synthesis of 2-Substituted 7-(β-D-Ribofuranosyl)pyrrolo[2,1-f]-1,2,4-triazines. A New Type of "Purine Like" C-Nucleoside

Masanori Hayashi, Akemi Araki, and Isamu Maeba*

*Faculty of Pharmacy, Meijo University, Yagotoyama, Tempaku-ku, Nagoya 468, Japan

Abstract

A versatile intermediate pyranulose glycoside (1) for C-nucleoside synthesis was treated with semicarbazides (3a) and (3b) to give the corresponding semicarbazones (4a) and (4b) in good yield. Treatment of 4a with concentrated hydrochloric acid in dioxane yielded 1-ureido-5-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)pyrrole-2-carboxaldehyde (5), which on heating in acetic acid gave 2-oxo-7-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)pyrrolo[2,1-f]-1,2,4-triazine (6a). Compond (4b) was treated by the same procedure to give 2-thioxo-7-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)pyrrolo[2,1-f]-1,2,4-triazine (7a) and 3-hydroxymethyl-6-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)pyridazine (8). The removal of the sugar protecting groups in 6a and 7a afforded the deprotected C-nucleosides (6b) and (7b).

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.575-587
Published online:
DOI: 10.3987/COM-91-5951
Four New Prenylated Flavonoids, Glyasperins A, B, C, and D 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

Abstract

Four new prenylated flavonoids, glyasperins A (1), B (2), C (3), and D (4), along with ten known compounds were isolated from the roots of Glycyrrhiza aspera. The structures of glyasperins A-D were elucidated by spectroscopic methods.

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Paper | Regular issue | Vol 34, No. 3, 1992, pp.589-597
Published online:
DOI: 10.3987/COM-91-5952
On the Structure of the Diels-Alder Adducts Obtained from (E)-3-Methoxycarbonylmethylene-2-oxoindoline with Unsymmetrical Butadiene Derivatives

Kunisuke Okada,* Morihide Kondo, Hideo Tanino, Hisae Kakoi, and Shoji Inoue

*Faculty of Pharmacy, Meijo University, Tenpaku, Nagoya 468, Japan

Abstract

The Diels-Alder reaction of (E)-3-methoxycarbonylmethylene-2-oxoindoline with trans- and cis-1,3-pentadienes gave a single product, respectively, in high yield. The structural features of these adducts were elucidated by proton nmr analysis and chemical transformations.

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18 data found. 1 - 18 listed