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. 16, No. 3, 1981
Published online:
■ Nuclear Magnetic Resonance Spectra of Heterocyclic Systems: The 15N Parameters of a Substituted Pyridone
C. A. Kingsbury,* M. D. Cliffton, S. Rajan, D. L. Durham, and J. H. Looker
*Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebrasa 68588, U.S.A.
Abstract
The 15N coupling constants to 13C and to 1H are reported for 2-hydroxymethyl-5-methoxy-1-phenyl-4-pyridone (1). The one-bond 15N-13C coupling constants are consistent with sp2 hybridized nitrogen. The 13C chemical shifts do not change much on protonation, but the 15N chemical shift undergoes a large change. The nmr data are discussed with regard to the question of the aromaticity of 4-pyridones. An improved synthesis of 1 is reported.
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■ Synthesis of Rutecarpine and Related Indole Alkaloids
Jan Bergman* and Solveig Bergman
*Department of Organic Chemistry, Royal Institute of Technology, SE-100 44 Stockholm, Sweden
Abstract
A new route to quinazolinocarboline alkaloids, involving elimination of CF3- in the final step has been developed.
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■ The Configuration Concerning the Mode of Biphenyl Lankage of Bisaknadinine
Jun-ichi Kunitomo,* Miyoko Satoh, Masatoshi Inoue, and Toshimasa Ishida
*Faculty of Pharmaceutical Science, Mukogawa-Women’s University, 11-68 Koushien Kyuban-Cho, Nishinomiya, Hyogo 663-8179, Japan
Abstract
The crystal structure of natural bisaknadinine has been determined by X-ray diffraction method demonstrating the absolute configuration concerning the mode of biphenyl linkage has been confirmed to be R-configuration (Ia).
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■ 2-Azabicyclo[3.2.0]heptane-3,4-diones (1). A Novel Epimerization Reaction of C7-Substitutents
Takehiro Sano,* Yoshie Horiguchi, and Yoshisuke Tsuda
*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan
Abstract
On treatment with bases, 7,7-disubstituted and 7-substituted 2- azabicyclo[3.2.0]heptane-3,4-diones rapidly epimerized at C7 to give a themodynamically more stable isomer (7-endo isomer in the cases of mono-substituted compounds) predominantly, then changed into dihydroazatropolones. The mechanism of this novel epimerization reaction was suggested as a homolytic cleavage and recombination of C1-C7 bond, which may be of a thermal process accelerated by formation of an anion on the adjacent nitrogen.
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■ 2-Azabicyclo[3.2.0]heptane-3,4-diones (2): Stereochemistry of the Photo-cycloadducts of 3-Ethoxycarbonyl-2-phenyl-Δ2-pyrroline-4,5-dione with Substituted Olefins
Takehiro Sano,* Yoshie Horiguchi, and Yoshisuke Tsuda
*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan
Abstract
The stereochemistries of photo-cycloadducts of 3-ethoxycarbonyl-2-phenyl-Δ2-pyrroline-4,5-dione with substituted olefins were established by chemical and spectroscopic means. Styrene- and butadiene-major adducts were 7-exo-isomers, while ethyl vinyl ether- and vinyl acetate-major adducts were 7-endo-isomers. The 7,7-disubstituted derivative, the isopropenyl acetate-adduct, was also established as an O-endo-isomer.
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■ 2-Azabicyclo[3.2.0]heptane-3,4-diones (3): Lewis Acid Catalysed Ring Expansion of 3-Ethoxy-Δ2-azabicyclo[3.2.0]heptan-4-ones: Synthesis of 2-Ethoxy-3-azatropones
Takehiro Sano,* Yoshie Horiguchi, Suetaka Kambe, and Yoshisuke Tsuda
*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan
Abstract
Treatment of 2-azabicyclo[3.2.0]heptane-3,4-dione imidic ester (6) with tin(IV) chloride gave the dihydroazatropolone 2-ethyl ethers (7) in moderate yields which were also obtained by reaction of dihydroazatropolones (2) with Meerwein reagent. DDQ oxidation of 7 gave 2-ethoxy-3-azatropones (8), which rearranged, on treatment with water, into ethyl pyridine 2-carboxylate (10). Spectroscopic data of azatropolone 2-ethyl ethers were also described.
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■ Bimolecular Products from the Reduction of Quinolines with Zinc and Hydrochloric Acid
I. Wesley Elliott,* Charles R. Montgomery, and Peter Yates
*Department of Chemistry, Fisk University, Nashville, Tennessee 37203, U.S.A.
Abstract
Comparison of the 13C nuclear magnetic resonance spectra of the bimolecular products 4a-4c obtained on reduction of 2-methylquinoline, 2,4-dimethylquinoline, and 6-bromo-2-methylquinoline, respectively, with zinc and hydrochloric acid with the spectra of the corresponding products from 8-methoxy-2-methylquinoline and 6-chloro-2-methylquinoline shows that the latter have the analogous bridged ring structures 4d and 4e, respectively, and not fused cyclobutanoid structures of type 1.
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■ Structures of Montrifoline and Delbine: Two New Furoquinoline Alkaloids from Monnieria trifolia L
J. Bhattacharyya* and Leila M. Serur
*Laboratório de Tecnologia Farmacêutica, Universidade Federal da Paraiba, 58051-970 João Pessoa, PB, Brazil
Abstract
Two novel furoquinoline alkaloids were isolated from Monnieria trifolia and their structures were determined on the basis of spectral characteristics and chemical transformation.
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■ Total Syntheses of (±)-Chanoclavine I and (±)-Dihydrosetoclavine
Mitsutaka Natsume* and Hideaki Muratake
*Research Foundation Itsuu Laboratory, 2-28-10 Tamagawa, Setagaya-ku, Tokyo 158, Japan
Abstract
Syntheses of the title ergot alkaloids 5 and 19a were achieved from the common intermediate 2, obtained by a series of reactions including our synthetic method of 4-alkylindoles.
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■ Efficient Synthesis of (R)-(—)-γ-Benzyloxymethyl-γ-butyrolactone from (D)-(+)-Mannitol
Seiichi Takano,* Emiko Goto, Michiyasu Hirama, and Kunio Ogasawara
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
Efficient synthesis of (R)-(-)-γ-benzyloxymethyl-γ-butyrolactone (10) has been developed using (D)-(+)-mannitol (1) as starting material.
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■ Pyrimidinylcyclopropanes. Synthesis and Reactions
Tetsuzo Kato,* Nobuya Katagiri, Akihiro Wagai, and Yumiko Katagiri
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
Reactions of trichloromethylpyrimidines (1 - 4) with dimethyl fumarate in the presence of t-butyl isocyanide and copper powder in benzene gave the corresponding dimethyl 3-chloro-3-(4- or 6-pyrimidinyl)cyclopropane-1,2-trans-dicarboxylates (5 - 8). Similar reactions with methyl vinyl ketone afforded the corresponding 2-acetyl-1-chloro-1-(4- or 6-pyrimidinyl)cyclopropanes (9 - 12). Pyrimidinylcyclopropanes (10 and 12), on treatment with sodium ethoxide, underwent ring opening of cyclopropane to give 1-pyrimidinyl-4-oxopentanes (13 - 16).
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■ A Note on the Oxidative Capacity of Benzofurazan Oxide
V. Alexanian, M. J. Haddadin,* C. H. Issidorides, and M. Z. Nazer
*Department of Chemistry, American University of Beirut, Beirut, Lebanon
Abstract
A method is described for the preparation of o-quinone dioximes from the reaction of benzofurazan oxide (or its congeners) with sodium dithionite, thiophenols, phenylhydroxylamine, and hydrazine derivatives. These, and other related reactions reported in the literature, are interpreted as two-electron transfer processes from reductant to benzofurazan oxide (oxidant), leading to the o-quinone dioxime anion.
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■ Synthesis of Pyrrolo[2,3-b]azepin-4-one Derivatives
Manhar M. Vora, Ching S. Yi, and C. DeWitt Blanton, Jr.*
*Department of Medical Chemistry and Pharmacognosy, College of Pharmacy, The University of Georgia, Athens, Georgia 30602, U.S.A.
Abstract
The Dieckmann reaction has been successfully applied for the first time in the synthesis of pyrrolo[2,3-b]azepin-4-ones.
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■ New Steroidal Heterocycles. Part XI. Total Synthesis of 1.6-Bisthiabenz[3,4]estra-3,5(10),8,14-tetraen-17-one
M. Vijaya Krishna and S. R. Ramadas*
*Department of Chemistry, Indian Institute of Technology, Madras, 600 036, India
Abstract
The total synthesis of the title compound (I) from isothiochroman-4-one (II) is described.
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■ Deoxygenation of 2,3-Disubstituted Quinoxaline 1,4-Dioxides
Fadia R. Homaidan and C. H. Issidorides*
*Department of Chemistry, American University of Beirut, Beirut, Lebanon
Abstract
The title compounds can be deoxygenated under very mild conditions by hexachlorodisilane, iodotrimethylsilane, trifluoroacetic anhydride-sodium iodide, and titanium tetrachloride-zinc dust.
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■ Covalently Linked Dimeric Porphyrins
David Dolphin,* John Hiom, and John B. Paine III
*Department of Chemisry, University of British Columbia, Vancouver 8, V5T 1W5, Canada
Abstract
The synthesis, spectral properties and applications of singly and multiply covalently linked bis- and tris- porphyrins, chlorins and bacteriochlorins are reviewed.
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■ On the Use of Lactones as Building Blocks in the Alkaloid Synthesis — A Review
Ganesh D. Pandey* and Kamala P. Tiwari
*Department of Chemistry, University of Allahabad, Allahabad, 211002, India
Abstract
Recent alkaloid syntheses involving the lactones have been reviewed with particular reference to isoquinoline and indole alkaloids.