HETEROCYCLES
An International Journal for Reviews and Communications in Heterocyclic ChemistryWeb Edition ISSN: 1881-0942
Published online by The Japan Institute of Heterocyclic Chemistry
Regular Issue
Vol. 53, No. 7, 2000
Published online:
■ Suggestion of Unexpected Sulfur Dioxide Mechanism for Deoxygenations of Pyridine N -Oxides with Alkanesulfonyl Chlorides and Triethylamine
Yoshiki Morimoto,* Hajime Kurihara, Takamasa Shoji, and Takamasa Kinoshita
*Department of Chemistry, Graduate School of Science, Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
Abstract
The reaction mechanism for unusual deoxygenations of pyridine N-oxides with alkanesulfonyl chlorides and triethylamine was explored. Some experimental facts suggested that sulfur dioxide generated in the reaction system might be responsible for the deoxygenations without chlorinations of the pyridine nucleus.
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■ (-)-Ampelopsin D is Different from (-)-Quadrangularin A
Masatake Niwa,* Junko Ito, Kenji Terashima, Tomoko Koizumi, Yoshiaki Takaya, and Ke-Xu Yan
*Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tenpaku, Nagoya 468-8503, Japan
Abstract
The structure of (—)-ampelopsin D, hydroxystilbene dimer, was reinvestigated using spectroscopic methods. Furthermore, the relative and absolute stereostructures were discussed on the basis of chemical transformation of (+)-ε-viniferin to (—)-ampelopsin D.
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■ β-Lactam Synthesis by Diastereoselective Condensation of Chiral 3-(p-Tolylsulfinyl)-2-furaldimine and Ester Enolates
Yoshitsugu Arai,* Shinya Yoneda, Tsutomu Masuda, and Yukio Masaki
*Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan
Abstract
Highly diastereoselective condensation of chiral sulfinyl-substituted furaldimine with lithium ester enolates has been achieved, affording (3R)-syn-β-lactams and/or (3R)-syn-β-amino esters, as the major products
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■ Palladium-catalyzed Asymmetric Allylic Alkylation Using Chiral P,N-Ligands
Takashi Mino,* Youichi Tanaka, Masami Sakamoto, and Tsutomu Fujita
*Department of Materials Technology, Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
Abstract
Palladium-catalyzed asymmetric allylic alkylation of 1,3-diphenyl-2-propenyl acetate (8) with a dimethyl malonate-BSA-LiOAc system has been successfully carried out in the presence of new chiral P,N-ligands 5 in good yields with good enan-tioselectives (up to 83% ee).
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■ Synthesis of Indolylpyrimidines via Cross-Coupling of Indolylboronic Acid with Chloropyrimidines: Facile Synthesis of Meridianin D
Biao Jiang* and Cai-guang Yang
*Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, China
Abstract
Palladium catalyzed cross-coupling reaction of 3-indolylboronic acid with 2,4-dichloropyrimidines proceeded regioselectively to yield indolyl- or bis(indolyl)pyrimidines in high yield, depending on the projection of 3-indolylboronic acid. The marine indole alkaloid meridianin D and an analogue were synthesised via the palladium catalyzed cross-coupling reaction as a key step.
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■ A Concise Access to 6-Azabicyclo[3.1.0]hexanes via High-Pressure
Promoted Cycloaddition Reaction of Azides to ABH
Minoru Ishikura,* Sayoko Kudo, Ayako Hino, Nobuyuki Ohnuki, and Nobuya Katagiri*
*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
Abstract
Cycloaddition reaction of electron-deficient azides (5a, b) to 2-azabicyclo[2.2.1]hept-5-en-3-one (ABH) (1) was accelerated by high-pressure, leading to a mixture of regioisomeric triazolines (6) in good yields. Then, 6 were in turn, through photolysis and ring opening sequences, converted to 6-azabicyclo[3.1.0]hexanes (8).
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■ Synthesis of (-)-Sugiresinol Dimethyl Ether Utilizing (-)-Quinic Acid
Keizo Matsuo,* Wakiko Sugimura, Yumiko Shimizu, Keiji Nishiwaki, and Hiroshi Kuwajima
*Faculty of Pharmaceutical Sciences, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502, Japan
Abstract
(-)-Sugiresinol dimethyl ether, a derivative of (-)-sugiresinol isolated from Cryptomeria japonica, was synthesized through 1,4-conjugate addition of arylmetal reagent to a substituted chiral 2-cyclohexen-1-one derived from (-)-quinic acid.
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■ Chemistry of Indoles Carrying a Basic Function. Part VI. Synthesis of a New Ring System with Indole Nucleus
István Moldvai, Mihály Balázs, Eszter Gács-Baitz, Tünde Platthy, Eszter Temesvári-Major, and Csaba Szántay*
*Institute of Chemistry, Chemical Research Center, Hungarian Academy of Sciences, H-1525 Budpest II, Pusztaszeri ut 59-67, P.O. Box 17, Hungary
Abstract
Stobbe condensed product half ester (2E;E-1,3,4,5-tetrahydrobenz[c,d]indole-5-ylidene-3’-ethoxycarbonylpropionic acid) afforded a monomer tetracyclic indole derivative (4; 5-ethoxycarbonyl-7-acetoxy-1H,9cH-3,4-dihydronaphto[c,d,e]indole) and a dimer (5; 5-ethoxycarbonyl-1H,9cH-3,4-dihydronaphto[c,d,e]indole-7-(O-E-1,3,4,5-tetrahydrobenz[c,d]indole-5-ylidene-3’-ethoxycarbonylethylpropionate) in an unexpected cyclisation.
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■ Solid-Phase Synthesis of 2-Phenyl-4-quinolinone Library via Flavylium Salt
Shingo Sato,* Yutaka Kubota, Hironobu Kumagai, Toshihiro Kumazawa, Shigeru Matsuba, Jun-ichi Onodera, and Masanobu Suzuki*
*Department of Chemistry and Chemical Engineering, Faculty of Engineering, Yamagata University, 4-3-16 Jyonan, Yonezawa 992-8510, Japan
Abstract
Fourteen 1-, 6-, 7-, 8-mono-, 7,8-di-, and 6,7,8-trisubstituted 2-(4’-hydroxy- and 4’-hydroxy-3’-methoxy)phenyl-4-quinolinones were conveniently synthesized by aqueous ammonia treatment of the flavylium salts obtained by the three-components condensation reaction of acetophenones, aldehydes, and ethyl orthoformate on a solid support with excellent purity and in overall yields of 11-59%.
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■ LI-F Antibiotics, a Family of Antifungal Cyclic Depsipeptides Produced by Bacillus polymyxa L-1129
Jun Kuroda, Toshio Fukai, Masataka Konishi, Jun Uno, Keiji Kurusu, and Taro Nomura*
*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan
Abstract
Twelve antifungal depsipeptide antibiotics named as LI-F03a, LI-F03b, LI-F04a, LI-F04b, LI-F05a, LI-F05b, LI-F06a, LI-F06b, LI-F07a, LI-F07b, LI-F08a and LI-F08b have been isolated from the fermentation broth of Bacillus polymyxa L-1129 by use of extensive preparative HPLC. Not only their intrinsic antifungal and anti-Gram positive bacterial activity, they also showed unique synergistic antifungal effect in combination with the azole group antifungal agents. The structural studies disclosed that they are cyclic depsipeptides composed of six amino acids (three of them, L-threonine, D-allo-threonine and D-alanine being in common among all components and other three amino acids variable) on which is substituted by a 15-guanidino-3-hydroxypentadecanoic acid.
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■ Synthesis of 2-Ethylthio-6-(3-hydroxy-1,2-O -isopropylidenepropyl)pteridin-4(3H )-one
Yonghan Kang,* Seungjin Kim, Youngchan Myoung, and Daejin Baek
*Department of Chemistry, Hanyang University, Ansan, Kyunggi-do 425-791, Korea
Abstract
A strategy has been described for the synthesis of 2-ethylthio-6-(3-hydroxy-1,2-O-isopropylidenepropyl)pteridin-4(3H)-one, which can be used as a useful intermediate for the conversion of neopterin to biopterin.
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■ Syntheses of Bis(3’-indolyl)-2(1H)-pyrazinones
Biao Jiang* and Xiao-Hui Gu
*Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, China
Abstract
The syntheses of 3,6-bis(3’-indolyl)-2(1H)-pyrazinone and 3,5-bis(3’-indolyl)-2(1H)-pyrazinone were described. Syntheses of 3,6-bis(3’-indolyl)-2(1H)-pyrazinone proceeded through the condensation of N-Boc-indolylglycine with indol-3-yl-N-methyl-O-methoxyglycinamide, and followed by reduction with LiAlH4 and cyclization of the resulting bisindolyl aldehyde-amine. 3,5-Bis(3’-indolyl)-2(1H)-pyrazinone was synthesized by cyclization of bisindolyl ketone amine in excess of ammonia under pressure.
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■ A Synthesis of Cytonin (Taiwanin A), an Antitumor Lignan
Weir-Torn Jiaang, Chih-Liang Wang, Albert Tseng, and Shui-Tein Chen*
*Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan, R.O.C.
Abstract
A new procedure for the synthesis of the antitumor substance: cytonin (taiwanin A) is described. Stobbe reaction, using diethyl succinate with piperonal in a 2:1 molar ratio, produced 2E,3E-dipiperonylidenesuccinic acid. Dehydration to the anhydride, followed by reduction with DIBALH gave hydroxy acid. Subsequent cyclization of the hydroxy acid resulted in 21% total yield of cytonin.
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■ The First and Simple Total Synthesis of Cappariloside A
Masanori Somei* and Fumio Yamada
*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
A lithium hydroxide promoted simple glycosylation of 4-hydroxyindole-3-acetonitrile with 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide was developed. Utilizing the method, the first and five steps total synthesis of cappariloside A was achieved from indole-3-carbaldehyde in 41% overall yield.
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■ A Convenient Method for the Synthesis of C-10 Alkylated Docetaxel Analogs Using Tris-(trimethylsilyl)silane as a Radical Mediator
Shin Iimura, Satoru Ohsuki, Kouichi Uoto, Kiyoshi Nakayama, Hirofumi Terasawa, and Tsunehiko Soga*
*New Product Research Laboratories IV, Daiichi Pharmaceutical Co., Ltd., 1-16-13, Kitakasai, Edogawa, Tokyo 134-8630, Japan
Abstract
Radical coupling has been investigated as a method for preparing Docetaxel analogs substituted at the C-10 position. C-10-Xanthate derivatives of 7-O-TES-10-deacetylbaccatin III were coupled with acrolein using organosilanes as radical mediators. Among the organosilanes that were investigated, tris(trimethylsilyl)silane gave the best results. This method provides C-10 alkylated baccatin III in good yield, and avoids the use of potentially toxic tributyltin hydride.
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■ Selective Electrocatalytic Oxidation of Amines Mediated by Decahydroquinolinyl-N-oxyl Radical
Yoshitomo Kashiwagi,* Futoshi Kurashima, Chikara Kikuchi, Jun-ichi Anzai, and Tetsuo Osa
*Graduate School of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan
Abstract
Electrocatalytic oxidation of amines was studied using (±)-trans,cis-4-benzoyloxy-2,2,8a-trimethyldecahydroquinolinyl-N-oxyl. The reaction with amines led to direct formation of carbonyl compounds in aqueous media in adequate conversion (> 78 %), high current efficiency (> 90 %) and high selectivity (100 %). Under anhydrous conditions, primary amines were also oxidized to the corresponding nitriles in satisfactory conversion (> 76 %), high current efficiency (> 89 %) and high selectivity (> 95 %).
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■ 2,3-Dialkylchromones from Mycobiont Cultures of the Lichen Graphis scripta
Yukiko Takenaka, Takao Tanahashi,* Naotaka Nagakura, and Nobuo Hamada
*Kobe Pharmaceutical University, 4-19-1 Motoyamakita-machi, Higashinada-ku, Kobe 658-8558, Japan
Abstract
From the cultures of spore-derived mycobionts of lichen Graphis scripta, three chromones, 5-hydroxy-2,3-dimethyl-7-methoxychromone (1), 5-hydroxy-3-hydroxymethyl-2-methyl-7-methoxychromone (2), 5-hydroxy-2-hydroxymethyl-3-methyl-7-methoxychromone (3), were isolated. Compound (1) has been characterized as a natural product for the first time. The structures of two new chromones (2) and (3)were established on the basis of spectroscopic evidences. This is the first instance of isolation of 2,3-dialkylated chromones from lichen mycobionts.
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■ Cyclodextrin Host-Guest Systems Containing Azaaromatic Moieties
Wanda Sliwa* and Barbara Dondela
*Institute of Chemistry, Pedagogical University, Al. Armii Krajowej 13/15, 42-201 Czestochowa, Poland
Abstract
The chemistry of cyclodextrin host-guest complexes containing azaaromatic moieties is reviewed. Systems with azaaromatic moiety appended to the host molecule and those including an azaaromatic guest are described.
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■ Ring Transformation of Pyridines and Benzo Derivatives under the Action of C-Nucleophiles
Sergey P. Gromov*
*Center of Photochemistry, Russian Academy of Sciences, 7a ul. Novatorov, Moscow, 117421, Russia
Abstract
The data on ring transformations of heterocyclic systems containing a pyridine ring on treatment with C-nucleophiles are generalized and described systematically over the period of up to 1999.