Regular Issue

Vol. 34, No. 11, 1992

12 data found. 1 - 12 listed
Communication | Regular issue | Vol 34, No. 11, 1992, pp. 2057 - 2060
Published online:
DOI: 10.3987/COM-92-6142
Novel Natural Colorants from Monascus anka U-1

Kyoko Sato, Satoshi Iwakami, Yukihiro Goda, Emi Okuyama, Kunitoshi Yoshihira, Takahiko Ichi, Yoshinobu Odake, Hiroshi Noguchi,* and Ushio Sankawa

*Faculty of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan


The structure of xanthomonasin A(C21H24O7), a natural colorant with a novel carbon skeleton (furanoisophthalide), produced by a mutant strain of Monascus anka, has been determined by the application of INADEQUATE experiment as well as by the variety of correlation spectroscopic techniques.

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Communication | Regular issue | Vol 34, No. 11, 1992, pp. 2061 - 2064
Published online:
DOI: 10.3987/COM-92-6153
A Facile Synthesis of Highly Functionalized Unsymmetrical Heterobiaryls Utilizing the Intramolecular Ullmann Coupling Reaction Directed by Salicyl Alcohol as a Template

Masami Takahashi, Tooru Kurada, Tsuyoshi Ogiku, Hiroshi Ohmizu, Kazuhiko Kondo, and Tameo Iwasaki*

*Department of Synthetic Chemistry, Research Laboratory of Applied Biochemistry, Tanabe Seiyaku Co., Ltd., 16-89 Kashima, Yodogawa, Osaka 532, Japan


Heterobiaryls (4) were synthesized in good yields utilizing the intramolecular Ullmann coupling reaction directed by salicyl alcohol as a template. The regioselective cleavage of the two ester bonds of 4 gave the highly functionalized unsymmetrical heterobiaryls having substituents which are incompatible with organometallic reagents.

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Paper | Regular issue | Vol 34, No. 11, 1992, pp. 2065 - 2077
Published online:
DOI: 10.3987/COM-92-6013
Syntheses of 3,8-Dihydroxyimidazo[1,2-a]pyridines and [1,2-a]pyrazines

Muriel Doise, Dominique Blondeau, and Henri Sliwa*

*Laboratoire de Chimie Organique et Environnement, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’ Ascq Cedex, France


3,8-Dihydroxyimidazo[1,2-a]pyridines and [1,2-a]pyrazines were prepared by condensation of glyoxal derivatives with methyl or benzyl ethers of 2-amino-3-hydroxypyridine and pyrazine followed by cleavage of the ether group.

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Paper | Regular issue | Vol 34, No. 11, 1992, pp. 2079 - 2093
Published online:
DOI: 10.3987/COM-92-6022
Syntheses of Functionalized N-(2-Pyridyl)-α-amino Acids and Esters by Ring Opening of Imidazo[1,2-a]pyridine

Muriel Doise, Dominique Blondeau, and Henri Sliwa*

*Laboratoire de Chimie Organique et Environnement, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’ Ascq Cedex, France


This report is devoted to the ring opening of the imidazole nucleus of functionalized imidazo[1,2-a]pyridines, by methanol in strong acid medium (HClO4) leading to esters of N-(2-pyridyl)-α-amino acids in which the heterocyclic moiety bears a functional group. Direct obtention of this kind of compounds could be achieved by condensation of glyoxal derivatives with ethers of 2-amino-3-hydroxypyridine or with 2-amino-3(or 5)-nitropyridine in methanolic perchloric acid.

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Paper | Regular issue | Vol 34, No. 11, 1992, pp. 2095 - 2108
Published online:
DOI: 10.3987/COM-92-6105
Approaches to the Generation of 2,3-Indolyne

Samuel C. Conway and Gordon W. Gribble*

*Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, U.S.A.


Several unsuccessful attempts to generate and trap 1-phenylsulfonyl-2,3-indolyne (4) from 2-lithio-3-bromo-1-phenylsulfonylindole (9) and 2-lithio-3-iodo-1-phenylsulfonylindole (12), generated by different methods, are described. The remarkable stability of 9 and 12 towards elimination parallels previous observations involving the stability of 2-lithio-3-bromobenzo[b]furan and other ortho-metalated halogenated five-membered ring heterocycles.

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Paper | Regular issue | Vol 34, No. 11, 1992, pp. 2109 - 2115
Published online:
DOI: 10.3987/COM-92-6117
GifIV Oxidation of Some Indolic Alkaloids*

Farès A. Farès and Christopher K. Jankowski*

*Départment de chimie, Université de Moncton, Moncton, N. B., Canada


The title oxidation was performed on four indolic alkaloids, β-carboline (1), reserpine (6), ajmaline (10) and ibogaine (11), leading to alicyclic hydroxylation of the starting materials. The numerous side products characterised during this reaction (due to reduction or coupling with solvent) as well as selective deuterium labelling experiments enabled us apart from the oxidation sites to study the Gif reaction mechanism.

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Paper | Regular issue | Vol 34, No. 11, 1992, pp. 2117 - 2121
Published online:
DOI: 10.3987/COM-92-6125
Facile Stereospecific Synthesis of α-Anomeric 2’-Deoxynucleosides

Kazuo Shinozuka,* Yoshiki Hirota, Tsutomu Morita, and Hiroaki Sawai

*Department of Chemistry, Faculty of Engineering, Gunma University, Tenjincho, Kiryu City 376, Japan


The coupling reaction of activated nucleobases, such as the sodium salts of N-benzoyladenine and 6-chloropurine and 2,4-bis-O-trimethylsilylthymine, with 1-α-chloro-2-deoxy-3,5-di-O-p-toluoylribofuranose (1) in a mixture of acetonitrile and tetrahydrofuran leads to the stereospecific formation of α-anomeric 2’-deoxynucleosides with satisfactory yields. The ratio of the distribution between the resulted α- and β-stereoisomers was about 3:1 in each case. The method is simple and applicable to the preparation of both purine and pyrimidine α-2’-deoxynucleosides.

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Paper | Regular issue | Vol 34, No. 11, 1992, pp. 2123 - 2130
Published online:
DOI: 10.3987/COM-92-6146
New Acridone Alkaloids from Citrus Plants

Yuko Takemura, Hiromi Uchida, Motoharu Ju-ichi,* Mitsuo Omura, Chihiro Ito, Kiyomi Nakagawa, Tomohisa Ono, and Hiroshi Furukawa

*Faculty of Pharmaceutical Sciences, Mukogawa Women’s University, Nishinomiya, Hyogo 663, Japan


The spectroscopic structure elucidations of five new acridone alkaloids named yukocitrine (1), yukodine (3), yukodinine (4), grandisine-III (6) and pummeline (7) from some Citrus plants were described.

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Paper | Regular issue | Vol 34, No. 11, 1992, pp. 2131 - 2136
Published online:
DOI: 10.3987/COM-92-6150
C-Nucleosides. 20. Ring Transformation of 5-Hydroxy-5-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)furan-2(5H)-one with 2-Aminothiophenol and 2-Aminoethanethiol to 1,5-Benzothiazepine and 1,4-Thiazine

Yasutaka Ito, Masakazu Wakimura, Chihiro Ito, and Isamu Maeba*

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


Treatment of 1 with 2-aminothiophenol afforded 2-[1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)carbonyl]-2,3-dihydro-1,5-benzothiazepin-4(5H)-one (2). Dehydrogenation of 2 with 2,3-dichloro-5,6-dicyano-p-benzoquinone and a trace amount of p-toluenesulfonic acid in benzene afforded 2-[1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)carbonyl]-1,5-benzothiazepin-4(5H)-one (3). The removal of the sugar protecting groups in 3 afforded 2-[1-(1,4-anhydro-2-deoxy-D-erythro-pent-1-enofuranosyl)carbonyl]-1,5-benzothiazepin-4(5H)-one (4) resulting from the abstruction by base of H-1’. Compound (1) was treated with 2-aminoethanethiol to give 3-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-5,6-dihydro-4H-1,4-thiazine-2-carboxaldehyde (5). Deprotection of the compound (5) with aqueous sodium carbonate afforded the deprotected compound (6).

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Paper | Regular issue | Vol 34, No. 11, 1992, pp. 2137 - 2142
Published online:
DOI: 10.3987/COM-92-6154
New and Efficient Syntheses of 4-Carbamoylquinuclidine

Takeo Kanai, Seiichiro Nomoto, Yuhki Komatsu, and Katsuyuki Ogura*

*Graduate School of Science and Technology, Chiba University, 1-33 Yayoicho, Inageku, Chiba 263, Japan


Two efficent routes starting from 4-carbamoylpiperidine or 2,2’,2"-trichlorotriethylamine were developed for preparing 4-cyanoquinuclidine which was hydrolyzed to give 4-carbamoylquinuclidine, a chemical modifier of cephalosporin antibiotics.

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Review | Regular issue | Vol 34, No. 11, 1992, pp. 2143 - 2177
Published online:
DOI: 10.3987/REV-92-446
Recent Advances in the Synthesis of Antibacterial Quinolones

Stanislav Radl* and Daniel Bouzard

*Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, N. J. 07110, U.S.A.


This review surveys the main synthetic approaches used for the construction of antibacterial quinolones, including aza analogs (naphthyridones, cinnolones) and condensed polycyclic analogs, with an emphasis on the more versatile methods which are potentially useful in other fields of heterocyclic chemistry. Simpler non-condensed monocyclic analogs, i.e., pyridone and pyridainone carboxylic acids are also briefly mentioned.

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Review | Regular issue | Vol 34, No. 11, 1992, pp. 2179 - 2229
Published online:
DOI: 10.3987/REV-92-448
Mechanisms and Rates of the Electrophilic Substitution Reactions of Heterocycles

Alan R. Katritzky* and Wei-Qiang Fan

*Department of Chemistry, University of Florida, Gainesville, FL 32611, U.S.A.


The mechanisms and rates of electrophilic substitution reactions, especially acid catalyzed hydrogen exchange and nitration, of heterocycles are discussed.

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12 data found. 1 - 12 listed