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. 2, 1981
Published online:
■ Cyclizations of N-Alkylazinium Cations with Bisnucleophiles. One-step Route to Furo[2,3-b]quinoxalines
Valery N. Charushin, Oleg N. Chupakhin,* and Anatoly I. Rezvukhin
*Department of Organic Chemistry, Urals Polythcnical Institute, Sverdlovsk, 620002, Russia
Abstract
N-Alkylquinoxalinium salts react with anions of β-diketones at a temperature below 20°C to yield endo-furo[2,3-b]quinoxalines.
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■ Synthesis and Acylation of 2-(2,5-Dihydro-1,3-thiazol-2-yl)-2-phenylhydrazonoacetic Acid Esters
Johann Gasteiger* and Ulrich Strauß
*Institut für Organische Chemie, Technische Universität München, Lichtenbergstrasse 4, D-85747 Garching, Germany
Abstract
The preparation of 2-(2,5-dihydro-1,3-thiazol-2-yl)-2-phenylhydrazonoacetic acid esters is described. Acylation of these compounds occurs at the sulfur atom with concomitant opening of the dihydrothiazole ring to yield 3-(Z-2-acylthiovinylimino)-2-phenylhydrazono-butanoic acid esters.
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■ Simple Synthetic Route to “Oxa-Deaza-Flavins” (2H-[1]-Benzopyrano[2,3-d]pyrimidine-2,4(3H)-diones)
David J. Blythin,* Martin S. Domalski, Young C. Kim, James Kuo, and Jen-Her Liu
*Department of Chemical Research, Medicinal Pharmaceutical Research Division, Schering-Plough Corporation, Bloomfield, NJ 07003, U.S.A.
Abstract
The preparation and reduction of substituted [1]-benzopyrano[2,3-d]pyrimidine-2,4(3H)-diones, “oxa-deaza-flavins”, (II), are described.
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■ Reactions of 4-Methylene-2-phenyl-2-oxazolin-5-ones with Sulfer Ylides
Otohiko Tsuge,* Michihiko Noguchi, and Hiroyuki Moriyama
*Research Institute of Industrial Science, Faculty of Engineering, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan
Abstract
The reaction of 2-phenyl-4-phenylmethylene-2-oxazolin-5-one with dimethyloxosulfonium methylide proceeded via a nucleophilic attack of the methylide on the carbonyl carbon in the oxazolinone with concurrent ring opening to give 1:1 adduct, dimethyloxosulfonium (2-benzamido)cinnamoylmethylide. On the other hand, dimethylsulfonium phenacylide reacted with 4-phenylmethylene-, 4-(p-acetoxyphenyl)methylene-, 4-styrylmethylene-, 4-(2-furyl)methylene-, 4-[3-(1-acetylindolyl)]methylene-, or 4-dimethylmethylene-2-phenyl-2-oxazolin-5-one to give two stereoisomeric spirocyclopropanes and/or γ-pyrone derivatives respectively, whose yields were dependent on the reaction conditions.
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■ A General Synthesis of 7,9-Dialkyladeninium Salts
Tozo Fujii,* Tohru Saito, Teruyo Sakuma, Masako Minami, and Isao Inoue
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Alkylations of N6-methoxy-9-methyladenine (I) and 9-alkyl-N6-benzyloxyadenines (II-IV) with MeI, EtI, and PhCH2Br in N,N-dimethylacetamide yielded the corresponding 7-alkylated derivatives (X, XIV-XVI), together with small amounts of the N6-alkylated isomers (V, VII-IX). Hydrogenolysis of the former compounds with hydrogen and Raney Ni produced 7,9-dialkyladenines (XI-XIII).
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■ The Structure of the Alkaloid Macarpine
Narao Takao, Miyoko Kamigauchi, Makiko Sugiura, Ichiya Ninomiya, Okiko Miyata, and Takeaki Naito*
*Kobe Women’s College of Pharmacy, Motoyamakita, Higashinad, kobe, Hyogo658, Japan
Abstract
The revised structure of the alkaloid macarpine (1c), which was isolated from both the plants and callus of Macleaya cordata, was proposed and unambiguously established by its total synthesis.
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■ Longikaurin C, D, E and F; New Antibacterial Diterpenoids from Rabdosia longituba
Tetsuro Fujita,* Yoshio Takeda, and Tetsuro Shingu
*Faculty of Pharmaceutical Sciences, University of Tokushima, Sho-machi, Tokushima 770-8505, Japan
Abstract
Four new diterpenoids, longikaurin C, D, E and F with antibacterial activity were isolated from the leaves of Rabdosia longituba and their structures were shown to be (3), (4), (5) and (6), respectively.
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■ Studies on Heterocyclic Compounds IV. Novel Diazotization Product of Ethyl 5-Aminofuran-2-carboxylate
Sheng-Chu Kuo,* Chun-Hsiung Wu, Chung-Chiee Wang, Akira Tanaka, and Chun-Chen Liao
*School of Pharmacy, China Medical College, Taichung 400, Taiwan, R.O.C.
Abstract
Using ethyl 5-aminofuran-2-carboxylate as starting material for diazotization following standard method, instead of obtaining the usual diazonium salt, we isolated and characterized an unexpected dimeric product—diethyl 2’3’4’5’-tetrahydro-5,5’-dioxo[2,3’-bifuran]-2,2’(5H)-dicarboxylate.
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■ Some Novel Reactions of Benzoxazole Derivatives with Dimethyl Acetylenedicarboxylate II
Norio Kawahara,* Michihiko Katsuyama, Tsuneo Itoh, and Haruo Ogura
*Hokkaido College of Pharmacy, 7-1 Katsuraoka-cho, Otaru 047-02, Japan
Abstract
2-Alkylbenzoxazole derivatives (1) reacted with dimethyl acetylenedicarboxylate (DMAD) in alcoholic solvents at room temperature to afford tricyclic compound (2), hydration product (3), solvent adduct (5) and ring-opened compounds (4 and 6). And the ring-opened compound (6) is a main product of photocycloaddition reaction of 1 with DMAD.
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■ A Two Synthon Approach to Δ15,17,19-Yohimbane Skeleton via a N5,N10-Methylenetetrahydrofolate Model. A Facile Route to β-Carboline Alkaloids
Hans Bieräugel, Henk C. Hiemstra, and Upendra K. Pandit*
*Laboratory of Organic Chemistry, Institute of Molecular Chemistry, University of Amsterdam, Nieuwe Achtergracht 129, 1018 WS Amsterdam, The Netherlands
Abstract
2[2-(1,5,5-Trimethyl-3-tosylimidazolidinyl)]-2-(2-methoxycarbonylphenyl)-1,3-dithiane (N5,N10-methylenetetrahydrofolate model 10) reacts in an acid catalyzed reaction with tryptamine to form the pentacyclic skeleton of Δ15,17,19-yohimbane in one practical step.
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■ Synthesis of Novel 1-Oxadethia-2-oxocephems
Kapa Prasad,* Helmut Hamberger, Peter Stütz, and Gerhard Schulz
*Sandoz Forschungsinstitut, 1235 Wien, Brunnerstraße 59, Austria
Abstract
Synthetic methods for the preparation of compounds 13, 14, and 15 are described utilising acetoxy azetidinone (4) as starting material.
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■ A Facile Route to (±)-Quebrachamine
Seiichi Takano,* Chikara Murakata, and Kunio Ogasawara
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
A facile route to (±)-quebrachamine (1), the parent base of the aspidosperma indole alkaloids, has been developed through halolactonization reaction.
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■ Synthesis of Some Pyrrolo[3,4-b]quinoxaline 4,9-Dioxides
Makhluf J. Haddadin* and M. Adnan Atfah
*Department of Chemistry, American University of Beirut, Beirut, Lebanon
Abstract
The syntheses of a number of derivatives of the, hitherto, unknown pyrrolo[3,4-b]quinoxaline 4,9-dioxides are reported.
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■ The Origin of the N-Formyl Group in Nature and the Biogenesis of Catharine and Catharinine
Natesan Murugesan* and Maurice Shamma
*Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, U.S.A.
Abstract
The presence of an N-formyl group in an alkaloid often points to an in vivo Baeyer-Villiger oxidative rearrangement of an iminium precursor. Vinblastine (3) is thus shown to be the most likely progenitor for the accompanying alkaloids catharine (1) and catharinine (2) in Catharanthus spp.
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■ Reactions of Harmaline and Its Derivatives. VII. Synthesis of 11-Methoxyindoloquinolizidines by Photochemical Cyclization of Enamine Interamediates
Atta-ur-Rahman* and Maryam Ghazala
*H. E. J. Postgraduate Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan
Abstract
Reactions of harmaline with benzyl halide and their ring substituted analogues affords enamine intermediates, photocyclization of which results in the formation of reserpine analogues in high yields. The procedure thus provides a synthetic approach to pharmacologically interesting substances from readily accessible precursors.
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■ Semisynthetic β-Lactam Antibiotics. IV. Synthesis of a New α-Hydrazinobenzyl-6α-methoxypenicilin
Goffredo Bolis, Piero Bellani, and Mario Pinza*
*Laboratories for Biomedical Research, ISF, Trezzano s/N, Milan, Italy
Abstract
Acylation of 6β-amino-6α-methoxypenicillanate (4b) with the α-methylenehydrazinoacid chloride (3b) afforded the new 6α-methoxy-6β-triazinonepenicillin (5).
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■ Synthesis of 4-Substituted Indoles and Their Elaboration to the Ergot Alkaloids
Alan P. Kozikowski*
*Department of Chemistry, University of Pittsburgh, Parkman Avenue & University Drive, Pittsburgh, PA 15260 , U.S.A.
Abstract
All of the synthetically important methods which have been developed for the preparation of 4-substituted indoles are reviewed. The use of these materials in the construction of the ergot alkaloids is discussed.