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. 31, No. 11, 1990
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■ Structure and Stereochemistry of Pseudolarolide-I, a Novel Cytotoxic Peroxytriterpene Dilactone from Pseudolarix kaempferi
Guo-Fu Chen, Zhu-Lian Li,* Cheng-Min Tang, Xiang He, Ke Chen, De-Ji Pan, Chang-Qi Hu, Donald R. McPhail, Andrew T. McPhail,* and Kuo-Hsiung Lee*
*Natural Products Laboratory, Division of Medicinal Chemistry and Natural Products, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, U.S.A.
Abstract
A novel cytotoxic peroxytriterpene dilactone, pseudolarolide I, has been isolated from the seeds of Pseudolarix kaempferi, and its structure and stereochemistry have been established from spectral data in conjunction with a single-crystal X-ray analysis.
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■ Secondary Metabolites by Chemical Screening. 11. Influence of the C-1 and C-29 Moieties in Nigericin on Complexation Behaviour and Biological Activity
Susanne Grabley, Peter Hammann,* Robert Klein, and Michael Magerstädt
*Hoechst AG, Postfach 80 03 20, D-65926 Frankfurt a. Main, Germany
Abstract
A reversible blocking of the C-29 hemiacetal in nigericin (1) was performed with LiBr in methanol to the acetal (6). Conversion of the carboxylic acid to the C-1 alcohol (7) and the ketone (9) and the subsequent deprotection yielded 8 and 10, respectively leaving F-rings intact. Complexation- and molecular medelling-studies with the nigericin alcohols (7) and (8) demonstrated the importance of noncyclic conformations.
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■ Formation of Two Dimers from Diphenyl-2-thienylmethyl Radicals and Their Structure
Akihiko Ishii, Motoaki Sugino, Juzo Nakayama,* and Masamatsu Hoshino
*Department of Chemistry, Faculty of Science, Saitama University, Saitama, Saitama 338-8570, Japan
Abstract
Diphenyl-2-thienylmethyl radical dimerizes in solution at room temperature to give 2-(diphenylmethylene)-5-(diphenyl-2-thienylmethyl)-2,5-dihydrothiopehen and a small amount of 5,5’-bis(diphenylmethylene)-2,2’,5,5’-tetrahydro-2,2’-bithiophene.
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■ The First Total Synthesis of (±)-Chanoclavine-I Acid and an Alternative Total Synthesis of (±)-Chanoclavine-I
Masanori Somei,* Harunobu Mukaiyama, Yoko Nomura, and Kyoko Nakagawa
*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
The total synthesis of (±)-chanoclavine-I acid was achieved for the first time. An alternative total synthesis of (±)-chanoclavine-I was also reported.
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■ Asymmetric Transformation. IV. Formation of the Optically Active Crystals of 1,4-Benzodiazepinooxazoles
Yutaka Okada,* Toyonori Takebayashi, Seiichi Aoki, and Sadao Sato
*Process Development Laboratories, Sankyo Co., Ltd., 1-2-58 Hiromachi, Shinagawa-ku, Tokyo 140, Japan
Abstract
Two 1,4-benzodiazepinooxazoles which afforded optically active crystals consisting of one enantiomer were newly found as additional example of the second-order asymmetric transformation which occurs between the enantiomers. All the optically active crystals of three 1,4-benzodiazepinooxazoles had the same molecular conformation and the same crystal structure.
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■ First Reactions of 1,4-Dimethylcarbazole-3-carbaldehyde N,N-Dimethylhydrazone with Carbo- and Azodienophiles
Conxa Borras-Almenar, Jose Sepulveda-Arques, Mercedes Medio-Simon, and Ulf Pindur*
*Department of Chemistry and Pharmacy, Institute of Pharmacy, University of Mainz, Saarstrasse 21, D-55122 Mainz, Germany
Abstract
Reactions of 1,4-dimethylcarbazole-3-carbaldehyde N,N-dimethylhydrazone (2) with carbo- and azodienophiles are described. Instead of giving the primarily expected Diels-Alder adducts, attack of the electrophilic dienophiles at the hydrazone unit of 2 occurs to furnish a 3-cyanocarbazole and, in one case, a carbazolyl-urazolylhydrazone.
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■ Studies on as-Triazine Derivatives. XVII. Chlorination of 5,6-Dimethyl-3-phenyl-as-triazine
Shoetsu Konno, Mataichi Sagi, Masaaki Yokoyama, and Hiroshi Yamanaka*
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
Homolytic chlorination of 5,6-dimethyl-as-triazine (1) with Cl2 gave 6-dichloromethyl-5-trichloromethyl-as-triazine (2) selectively. Structural determination of 2 by chemical method and synthesis of 5-amino-6-formyl-as-triazine derivatives are described.
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■ Reaction of Pyridazine N-Oxides with Pyridynes: Formation of the First Examples of Pyrido-oxepins
Jyoji Kurita, Naoki Kakusawa, Shuji Yasuike, and Takashi Tsuchiya*
*Faculty of Pharmaceutical Sciences, Hokuriku University, 3-Ho, Kanagawa machi, Kanazawa 920-1181, Japan
Abstract
Reaction of pyridazine N-oxides (3) with pyridynes and quinolynes (2) gave the corresponding novel fully unsaturated pyridooxepins (4-6) and quino-oxepins (13-15) via the cycloadducts (11).
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■ Preparation of 6-Hydroxy-2H-pyran-3(6H)-one from 2-Furylcarbinol by Photooxidation. Synthesis of a Pheromone of Vespa orientalis
Yueh-Hsiung Kuo* and Kae-Shyang Shih
*Department of Chemistry, National Taiwan University, Roosevelt Road Section 4, Taipei 106, Taiwan, R.O.C.
Abstract
Photooxidation of 2-furylcarbinols followed by reduction with triphenylphosphine afforded 6-hydroxy-2H-pyran-3(6H)-ones in excellent yield. The method was applied to synthesis of 6-undecyltetrahydro-2-pyrone, a pheromone of Vespa orientalis.
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■ Palladium-catalyze Arylation of Furan, Thiophene, Benzo[b]furan and Benzo[b]thiophene
Akihiro Ohta,* (the late) Yasuo Akita, Teruya Ohkuwa, Mari Chiba, Ryuichi Fukunaga, Ayako Miyafuji, Takako Nakata, Norio Tani, and Yutaka Aoyagi
*Tokyo College of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
Abstract
Treatment of π-electron sufficient aromatic heterocycles such as furan, thiophene, benzo[b]furan and benzo[b]thiophene with aryl bromides in the presence of tetrakis(triphenylphosphine)palladium gave the corresponding 2-aryl aromatic heterocycles.
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■ Indirect Electrochemical Oxidation of 4-Picoline and Its N-Oxides to Pyridine-4-aldehyde Diacetate with Electrogenerated Cobalt(III) Acetate in an In-Cell Process
Magdi Abdel Azzem and Eberhard Steckhan*
*Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, D-5300 Bonn 1, Germany
Abstract
The indirect electrooxidation of 4-picoline and its N-oxide with in situ electrogenerated Co(III) acetate has been studied. Pyridine-4-aldehyde diacetate was obtained in good ield (45 - 68%), if the electrolysis was performed in acetic anhdride at 20 °C in an undivided cell under controlled current conditions.
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■ Pyridazine Derivatives, IX. Synthesis of 2H-Pyridazin-3-ones with Aroylpiperazinyl Groups
Enrique Ravina,* Carmen Teran, Lourdes Santana, Neftali Garcia, and Isabel Estevez
*Department of Organic Chemistry, Laboratory of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Santiago, 15706 Santiago de Compostela, Spain
Abstract
Several 2H-pyridazin-3-ones with phenyl- or 2-furoylpiperazinyl group, have been prepared. 6-Phenyl-5-(N4-aroyl-N1-piperazinyl)-2H-pyridazine-3-ones were obtained by nucleophilic substitution of the chlorine atom of 6-phenyl-5-chloro-2H-pyridazin-3-one or alternatively, by aroylation of N1-piperazinyl-2H-pyridazin-3-one. Also, 6-phenyl-5-(N4-aroyl-N1-piperazinylmethyl)-2H-pyridazin-3-ones were prepared by displacement of the bromine in 6-phenyl-5-bromomethyl-2H-pyridazin-3-one.
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■ Chiral Prodyes. Ethers and Esters of Dihydrofluorescein, Part 1: Dibenzyldihydrofluorescein (DBDF) a New Reagent
Dragana Tadic and Arnold Brossi*
*Natural Products Section, Laboratory of Structural Biology, NIDDK, National Instutute of Health, Bethesda, Maryland 20892-0815, U.S.A.
Abstract
Ethers and esters of dihydrofluorescein (4) were prepared by chemical modification of the benzyl ester (6), obtained by benzylation of fluorescein (1), and reduction of benzyl ester (3) with sodium borohydride.
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■ Fused Imidazophenothiazines: Synthesis of 2-Methyl-3-phenyl-6H-imidzo[4,5-c]phenothiazine
Pilar López-Alvarado, Carmen Avendaño,* Mercedes T. Grande, and J. Carlos Menéndez
*Departamento de Química Orgánica y Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain
Abstract
A new and reliable procedure for the multigram-scale preparation of 2-methyl-1-phenyl-5-phenylaminobenzimidazole (6) is reported. Bernthsen thionation of 6 leads to 2-methyl-3-phenyl-6H-imidazo[4,5-c]phenothiazine (9), whose structure was established through a detailed mono- and bidimensional 1H-nmr and 13C-nmr spectroscopic study of model compounds.
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■ Anomalous Behaviour in Some Nucleophilic Ring Opening of Furyl-2-oxirane
Benito Alcaide, Pilar Areces, Elisabeth Borredon, Cristina Biurrun, Javier P. Castelles, and Joaquín Plumet*
*Departamento de Química Orgánica, Facultad de Química, Universidad Complutense de Madridas, Ciudad Universitaria, E-28040 Madrid, Spain
Abstract
The behaviour of furyl-2-oxirane in some nucleophilic ring opening reactions was studied.
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■ New 7-Anilinobenzo[b][1,8]phenanthrolines
Eugenia Sánchez, Carmen del Campo, Carmen Avendaño,* and Emilio Llama
*Departamento de Química Orgánica y Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain
Abstract
The synthesis and 1H nmr spectroscopy of a series of 7-anilinobenzo[b][1,8]phenanthrolines are reported.
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■ Ring Opening 2-Acylamino-4,5-dihydro-3-furancarbonitriles by Use of Titanium (IV) Chloride
Hiroshi Maruoka, Kenji Yamagata, and Motoyoshi Yamazaki*
*Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan
Abstract
The ring opening of 2-acylamino-4,5-dihydro-3-furanocarbonitriles (1a-f) with titanium (IV) chloride gave the corresponding N-acyl-4-chloro-2-cyanobutanamides (2a-f). On treatment with potassium carbonate, compounds (2a-f) were converted to the corresponding N-acyl-1-cyanocyclopropanecarboxamides (3a-f). On the other hand, the reaction of 2-benzamido-4,5-dihydro-3-thiophenecarbonitriles (4a-c) with titanium (IV) chloride gave the corresponding 2-benzamido-4,5-dihydro-3-thiophenecarboxamides (5a-c).
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■ Pyridine Synthesis via Anodic Oxidation of 1-Acyldihydropyridines
Daniel L. Comins* and Michael O. Killpack
*Department of Chemistry abd Biochemistry, Utah State University, Logan, Utah 84332-0300, U.S.A.
Abstract
The preparation of several substituted pyridines via anodic oxidation of 1-acyldihydropyridines is reported.
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■ Reaction of 1-(1-Alkoxyalkyl)-1H-1,2,4-triazole with Amides
Shunsaku Ohta,* Akihiko Maruyama, Ikuo Kawasaki, Shoko Hatakeyama, Michiyo Ichikawa, and Tomoko Guro
*Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8412, Japan
Abstract
1-(1-Alkoxyalkyl)-1H-1,2,4-triazoles (4) were prepared by treating acetals (1) with 1H-1,2,4-triazole (2) in the presence of pyridinium p-toluenesulfonate (3). the alkoxy group of 4 was substituted with -NR4COR3 group by treating with carboxamides to give various 1-(1-acylaminoalkyl)-1H-1,2,4-triazole (6) in variable yields.
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■ Reaction of Colchiceinamide with Phosgene and with Thiophosgene: Structures and Antitubulin Activity of Tetracyclic Oxazolones, Oxazolethiones and Thiazolones of the Colchicine Series
Anjum Muzaffar, Ernest Hamel, and Arnold Brossi*
*Natural Products Section, Laboratory of Structural Biology, NIDDK, National Instutute of Health, Bethesda, Maryland 20892, U.S.A.
Abstract
Colchiceinamide (5) on reaction with phosgene and thiophosgene in the presence of triethylamine afforded tetracyclic compounds (7) and (8) respectively. Treatment of oxazolethione (8) with sodium hydroxide afforded thiazolone (9). All three tetracyclic compounds had very high negative specific rotations, but none of them inhibited tubulin polymerization in vitro.
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■ Stereoselectivities in the Coupling Reaction between Silylated Pyrimidine Bases and 1-Halo-2,3-dideoxyribose
Hiroshi Kawakami,* Takashi Ebata, Koshi Koseki, Katsuya Matsumoto, Hajime Matsushita, Yoshitake Naoi, and Kazuo Itoh
*Life Science Research Laboratory, Japan Tobacco Inc., 6-2, Umegaoka, Midori-ku, Yokohama, Kanagawa 227-8512, Japan
Abstract
Coupling reactions between 1-chloro-2,3-dideoxyribose and silylated pyrimidines between have been examined from the point of stereoselectively. When the reaction was carried out in chloroform, the selectively was in the anomeric ratio of α:β-4:6. On the other hand, the presence of tertiary amine raises the selectively to α:β-7:3,
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■ 2,4,6-Tripyridino-1,3,5-triazine Trichloride, a New and Mild Esterification Agent for Preparation of Penicillin Esters
Masayuki Murakami,* Makoto Hajima, Fumitaka Takami, and Mitsuru Yoshioka
*Shionogi Research Laboratories, Shionogi & Co. Ltd., Fukushima-ku, Osaka 553-0002, Japan
Abstract
Cyanuric chloride reacted with 3 molar equivalents of pyridine to give 2,4,6-tripyridino-1,3,5-triazine trichloride, which was found to condense penicillines with alcohols under mild conditions ot afford penicillin esters in good yields. Application to preparation of cephalosporin esters also is discussed.
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■ The Reactivity fo 2-Iminobenzo[α]quinolizidines towards 2-Mercaptoacetic Acid
J. Carlos Menéndez and Mónica M. Söllhuber*
*Departamento de Química Orgánica y Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain
Abstract
The reaction between 2-aminobenzo[a]quinolizidines (2) and mercaptoacetic acid under a variety of conditions led to the thiazolo[2,3-a]isoquinoline derivative (5) instead of the expected spiro compound (1). The same result was obtained when the reaction was carried out on ketone (3). Modified reaction conditions allowed the preparation of an example of structure (1).
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■ Asymmetric Synthesis of a Piperazine Alkaloid
Seiji Takeuchi,* Yoshiaki Ohgo, Norikazu Miyoshi, Chung-gi Shin, and Yasuchika Yonezawa
*Niigata College of Pharmacy, 5-13-2 Kamishin’ei-cho, Niigata 950-2081, Japan
Abstract
A piperazine alkaloid, (2S,5S)-2,5-dibenzyl-1,4-dimethylpiperazine, was synthesized by reduction of (3S,6S)-3,6-dibenzyl-1,4-diemthyl-2,5-piperazinedione which was prepared by a catalytic asymmetric hydrogenation of the corresponding 3,6-dibenzylidene derivative.
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■ Some Observations on the Regioselective Ring Opening of Tetrahydro-1,3-oxazinium Methiodides by Sodium Borohydride in Alcholic and Etheral Solvents
Angel Alberola, Celia Andrés, Manuel Delgado, Alfonso González, and Rafael Pedrosa*
*Deparamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, 47005 Valladolid, Spain
Abstract
2-Substituted N-benzyl-N-methyltetrahydro-1,3-oxazinium iodides react with sodium borohydride in anhydrous THF leading to a mixture of 3-alkoxypropylamines and their borane complexed. On the contrary, when anhydrous methanol or ethanol is used as solvent, the corresponding transacetalization product is obtained as single compound.
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■ Synthesis of New Quinoline Alkaloids of Chiococca alba
Yoshiyasu Kitahara, Masaro Shimizu, and Akinori Kubo*
*Meiji Pharmaceutical University, 1-35-23 Nozawa, Setagaya-ku, Tokyo 154, Japan
Abstract
Two new quinoline alkaloids, 5,7-diemthoxy-4-(4-methoxyphenyl)-2(1H)-quinolinone (1) and 8-hydroxy-5,7-dimethoxy-4-(4-methoxyphenyl)-2(1H)-quinolinone (2) were synthesized.