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. 27, No. 4, 1988
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■ Preparation of 1-Tosyl-2- and 3-Pyrrolidinones via Ketenes and Carbenes
Antonio Saba* and Antonio Selva
*Department of Chemistry, University of Sassari, Via Vienna 2, I-07100 Sassari, Italy
Abstract
Catalytic decomposition of 1-diazo-4-tosylamino-2-butanone 1a, -2-pentanone 1b, and -2-hexanone 1c, results in the quantitative formation of the 1-tosyl-3-pyrrolidinones 2a, 2b and 2c, while the photolysis afforded the rearranged esters, 3a, 3b and 3c, or the unexpected 1-tosyl-2-pyrrolidinones 4a, 4b and 4c depending on the solvent employed.
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■ A Total Synthesis of (±)-Corydalic Acid Methyl Ester
Robin D. Clark and Jahangir
*Institute of Organic Chemistry, Syntex Research, Palo Alto, California 94304, U.S.A.
Abstract
A highly stereoselective synthesis of (±)-corydalic acid methyl ester (1) is reported. The key step involved cyclocondensation of the lithio derivative of amide 6 with imine 7 which afforded the trans-3-aryl-4-methyl-3,4-dihydro-1(2H)-isoquinolone 5 which was further elaborated to 1.
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■ Syntheses of Carbacepham and Carbacephem Ring System by Employing Radical Cyclization
Tetsuji Kametani,* Shih-Der Chu, Akira Itoh, Sayuri Maeda, and Toshio Honda
*Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
Radical cyclizatlon reaction was successfully applied to the construction of carbacepham and carbacephem ring system.
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■ Alkylation of Isolated Thiamin Ylide
Hirohiko Sugimoto and Kentaro Hirai*
*Shionogi Research Laboratories, Shionogi & Co. Ltd., Fukushima-ku, Osaka 553-0002, Japan
Abstract
Alkylation of isolated thiamin ylide (TY, 3) in EtOH under the neutral conditions afforded thiamin (TH+C1-,1) and the alkylated yellow form 4, which provides direct chemical evidence for the disproportionation of thiamin ylide into the ion pair of the yellow form (TH+YF-,6)in a protic solvent.
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■ 2-t-Butyl-5-chloro-6-nitrobenzoxazole: A Practical Synthetic Intermediate for 4-Aryloxy-5-nitro-2-aminophenols
Mitsunori Ono,* Katsuyoshi Yamakawa, Hidetoshi Kobayashi, and Isamu Itoh
*Ashigara Research Laboratories, Fiji Photo Film Co., Ltd., 210 Nakanuma, Minamiashigara, Kanagawa 250-0123, Japan
Abstract
On the examination of the anomalous reactivities of several nitrobenzoxazole derivatives 2a-e toward acids and bases it has been found that 2-t-butyl-5-chloro-6-nitrobenzoxazole 2c serves as one of the most convenient and practical synthetic intermediates for 4-aryloxy-5-nitro-2-aminophenols.
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■ Synthesis of Hypoxanthine 7-Oxide, a New N-Oxide at the 6-Oxopurine Level
Kazuo Ogawa, Tohru Saito, Fujio Nohara, Masahiro Nishii, Taisuke Itaya, and Tozo Fujii*
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Hypoxanthine 7-oxide (IV) has been synthesized for the first time from 6-chloro-5-nitro-4(3H)-pyrimidinone (I) through the intemediates II and V; catalytic hydrogenolysis, methylation followed by catalytic hydrogenolysis, and isomerization under acidic conditions of IV supported the correctness of the assigned structure.
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■ Heterosteroids via Organoiron Complexes: A Simple Route to 6-Oxa as well as 6-Keto-6a-oxa-D-homo-aromatic Steroids
Enrico Mincione, Paolo Bovicelli, and Maria Luigia Forcellese
*Centro CNR per lo Studio della Chimica delle Sostanze Organiche Naturali, Dipartmento di Chimica, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, 00185 Roma, Italy
Abstract
A simple route via organoiron complexes to 6-oxa as well as 6-Keto, 6a-oxa D-homo-aromatic steroids is reported.
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■ C-(11)-Epi-deoxyarteether: Formation and Structure
Lourdes Dominguez Gerpe, Herman J. C. Yeh, Qian-Sheng Yu, Arnold Brossi, and Judith L. Flippen-Anderson*
*Section of Medicinal Chemistry, Laboratory of Bioorganic Chrmistry, NIDDK, National Institute of Health, Bethesda, MD 20892, U.S.A.
Abstract
Acid catalyzed etherification of deoxydihydroqinghaosu (1) with ethanol saturated with hydrogen chloride afforded 11-epi-deoxyarteether (5). Compound 5 also was obtained from deoxyethern 2 and 3 and the vinylic ether 4 under the same reaction conditions. The configuration at C-l1 and C-12 of 5, strongly supported by 1H-nmr data, has been confirmed by X-ray analysis.
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■ Transformation of Amines and N-Heteroarylformamidines into Esters of Substituted β-Amino-α,β-dehydro-α-amino Acids
Branko Stanovnik,* Julij Svete, Miha Tisler, Lilijana Zorz, Ales Hvala, and Igor Simonic
*Department of Chemistry, E. Kardelj University, Murnikova 6, 61000 Ljubljana, Slovenia
Abstract
Esters of substituted β-amino-α,β-dehydro-α-amino acids 5 were prepared either by transformation of N-heteroaryl-N,N-dimethylformamidines 2 with 3 into 4, followed by ring opening, or by treatment of primary or secondary amines 1 with 9.
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■ Carbon-13 Nmr Assignments of Berberine and Sanguinarine
Gábor Blaskó, Geoffrey A. Cordell,* Sutatip Bhamarapravati, and Chiristpher W. W. Beecher
*Program for Collaborative Research in the Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 833 South Wood St., Chicago, IL 60612-7231, U.S.A.
Abstract
Unambiguous proton and carbon-13 nmr assignments for the proroberberine alkaloid, berberine (1) and for the benzo[c]phenanthridine alkaloid, sanguinarine (2) were accomplished through the judicious use of APT, CSCM 1D and selective INEPT spectroscopy.
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■ Heterocycles from Nitrile Imines. Part 1. 1,2,3,4-Tetrahydro-1,2,4,5-Tetrazines
Mustafa M. El-Abadelah,* Ahmad Q. Hussein, Marwan R. Kamal, and Khaled H. Al-Adhami
*Chemistry Department, Faculty of Science, University of Jordan, Amman 11942, Jordan
Abstract
The interaction between ketohydrazones and nitrile imines provides a new and direct synthetic route to 1,2,3,4-tetrahydro-1,2,4,5-tetrazines. Elemental analysis and spectral data are consistent with the assigned tetrazine ring system.
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■ Hetisine Derivatives Part 3. Rearrangement of 11-Acetyl-2,13-didehydrohetisine and 13-Dehydro-2,11-Diacethylhetisine
Qingping Jiang, Jan A. Glinski, Balawant S. Joshi, Joseph A. Maddry, M. Gary Newton, and S. William Pelletier*
*Department of Chemistry, Institute for Natural Products Research, The University of Georgia, Chemistry Building, Athens, Georgia 30602-2556, U.S.A.
Abstract
Heating 11-Acetyl-2,13-didehydrohetisine (1) with apueous potassium carbonate in methanol afforded a rearrangement product, C20H25NO4,mp 313-315°C. The structure of this compound has been shown to be 4 by an X-ray crystallographic study. Mild treatment of 13-dehydro-2,11-diacetylhetisine (5) with base gave 2-acetyl-13-dehydro-11-epihetisine (7). Under refluxing conditions, 5 gave the rearrangement compound 8. The structure of 8 was assigned by chromium-trioxidepyridine oxidation to give 4.
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■ Characterization and Photochemical Reactivity of Triphenodioxazine N-Oxides
Adele Bolognese, Giulia Scherillo, and Angelo Albini
*Dipartimento di Chimica Organica e Biologica, Università di Napoli "Federico II", Via Mezzocannone 16, I-80134 Napoli, Italy
Abstract
N-Oxidation of triphenodioxazine (1) by m-chloroperbenzoic acid in choroform yields the corresponding 7-oxide (2) and 7,14-dioxide (3). Their coloured solutions in organic solvents are very sensitive to light. Irradiation in the visible in various solvents leads to deoxygenation. The photoreaction of compound 3 in chloroform yields also N (7)-(6’-triphenodiaxazinyl)-3,7-dihydrotriphenodioxazin-3-one (4) and the corresponding N-oxides 5 and 6, as well as 1-, 3- and 13-chlorotriphenodioxazine 7-oxides (7-9). The nature of the excited state of these N-oxides is discussed and a mechanism for product formation is proposed.
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■ Synthesis of Pyrrolizidines and Related Compounds by Aldol Cyclization of N-[α-(Methylthio)acetyl]-α-aminoaldehydes
Masazumi Ikeda,* Suzumi Harada, Atsuko Yamasaki, Katsuko Kinouchi, and Hiroyuki Ishibashi
*Kyoto Pharmaceutical University, Misasagi-Shichonocho, Yamashina, Kyoto 607-8414, Japan
Abstract
Treatment of 1-[α-(methylthio)acetyl]-2-pyrrolidinecarbaldehyde with sodium hydride in tetrahydrofuran (THF) gave the aldol condensation product, 5,6,7,7a-tetrahydro-2-methylthlo-3H-pyrrolizin-3-one. However, when the same aldehyde was treated with sodium hydroxide in aqueous THF, 5,6,7,7a-tetrahydro-7a-hydroxy-3-methylthio-3H-pyrrolizin-3-one was obtained. These reactions were applied to the synthesis of indolizidine and pyrrolo[1,2-a]indole derivatives.
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■ Remote Induction of the Condensation of p-Nitrobenzaldehyde on the Methylene Group of 5-Hydroxy-2-coumaranone
Michel Barbier*
*Institut des Chimie des Substances Naturelles, C.N.R.S., 1 avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France
Abstract
(Z)-5-Hydroxy-3-(p-nitrobenzylidene)-2-coumaranone ((Z)-p-nitromarginalin) is obtained in 92% yield by reaction of p-nitrobenzaldehyde with 5-hydrony-2-coumaranone. The same condensation carried out with 2-coumaranone gives a mixture of (Z)- and (E)-p-nitrobenzylidene-2-caumaranones (72% yield) in a 2:1 ratio. In a discussion taking also into account previous results in the series, it is concluded that the 5-hydroxyl group exerts a remote induction in the orientation of the intermediate secondary alcohol, stabilized through chelation with the lactone carbonyl group. Such a long distance effect is in agreement with the requirements of the Cram’s rule, leading in this particular case to a high stereoselectivity in the final dehydrated ene-lactone.
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■ Alkaloids from the Leaves of Alstonia macrophylla
Atta-ur-Rahman,* Farzana Nights, and Mohammad Iqbal Choudhary
*H. E. J. Postgraduate Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan
Abstract
Alstonia macrophylla Wall, of Sri Lankan origin has yielded a new picraline alkaloid, “alstopicralamine” (1), the structure of which was established by using modern spectroscopic techniques. A known base vincamajine (2) was also isolated for the first time from the leaves of A.macrophylla.
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■ New Reractions of 2-Vinylindoles with Azodienophiles: Diels-Alder Reaction versus Michael-type Addition
Ulf Pindur* and Myung-Hwa Kim
*Department of Chemistry and Pharmacy, Institute of Pharmacy, University of Mainz, Saarstrasse 21, D-55122 Mainz, Germany
Abstract
The reactions of donor- and acceptor-substituted 2-vinylindoles with azodienophiles such as, for example, diethyl azodicarboxylate (DEAD) and 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) have been examined. Whereas DEAD gives rise to both Diels-Alder and Michael adducts, PTAD reacts preferentially to give novel cycloadducts with pyridazinoindole-type structures.
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■ Convenient Synthesis and Properties of Water Soluble Cyclodextrin Capped Mesoporphyrinatoiron
Takeshi Kato and Yushin Nakamura*
*Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan
Abstract
The β-cyclodextrin-capped porphyrin was synthesized by a convenient procedure for a coupling reaction between diamino-β-cyclodextrin and mesoporphyrin dithiazolidine-2-thione in aqueous media. The thiazolidine compound was prepared by a condensation of mesoporphyrin and thiazolidine-2-thione in the presences of dicyclohexylcarbodiimide and N,N’-dimethylaminopyridine. The properties of the cyclodextrin capped heme were examined.
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■ New Generation of 1,3-Dipoles from Organosilicon Compounds and Syntheses of Heterocycles
Yoshiyasu Terao, Masahiro Aono, and Kazuo Achiwa*
*Schol of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
Abstract
Recent development of the cycloaddition involving desilylation process has opened a new field in 1,3-dipolar cycloaddition chemistry. This review deals with the new methods for the generation of azomethine and thiocarbonyl ylides, and their cycloaddition reactions.
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■ Chiral Syntheses of Benzo[a]quinolizidine-type Alangium Alkaloids
Tozo Fujii,* Masashi Ohba, and Shigeyuki Yoshifuji
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Nineteen benzo[a]quinolizidine alkaloids isolated so far from Alangium plants are structurally classified into four types (I-IV), and studies on chiral syntheses of these I-IV-type alkaloids are reviewed with particular emphasis on the synthetic strategies and tactics employed. It has been found that chiral syntheses of all of these types of alkaloids are possible through the “cincholoiponincorporating route” or the “lnctim ether route”, and the absolute configurations of four II-type, two III-type, and one IV-type alkaloids have been established by such syntheses. An extension of the “lactim ether route” to the synthesis of (-)-ochropposinine [(-)-99g] has unequivocally established the absolute stereochemistry of this Ochrosia alkaloid.
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■ Natural Product Syntheses Utilizing 4-Alkoxycarbonyloxazoles as β-Hydroxy-α-amino Acid Synthons
Takayuki Shioiri* and Yasumasa Hamada
*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
Abstract
The utility of 4-alkoxycarbonyloxazoles as latent β-hydroxy-α-amino acids in the synthesis of amino sugars and amino acids is described.