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. 23, No. 11, 1985
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■ A Novel Thia[3,2]metacyclophan-ene with an Unexpected Preference for the Syn Conformation
Yee-Hing Lai*
*Department of Pharmacy, National University of Singapore, Lower Kent Ridge Road, 119260, Singapore
Abstract
Phenanthro(10,11-l)-2-thia[3.2]metacyclophan-10-ene 6 has been found by 1H NMR studies to exist in the unexpected syn conformation. Comparison with conformational barriers in related systems suggest the absence of ring flipping in 6.
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■ First Observation of Cation Radicals in the Cycl[3.2.2]azine System: 18π Electron Structure of 1,2,3,4-Dibenzocycl[3.2.2]azines as Revealed by ESR Analsys
Kiyoshi Matsumoto,* Jun Yamauchi, and Takane Uchida
*Graduate School of Human and Environmental Studies, Kyoto University, Yoshida-Nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan
Abstract
The cation radicals can be generated by annulation of the dibenzo groups to the cycl[3.2.2]azine system. The use of unpaired electron density as a probe for electronic structure shows (ESR analysis) that the 1,2,3,4-dibenzocycl[3.2.2]azines constitute a novel 18Π peripheral conjugate system in spite of large resonance stabilization of benzene nucleus.
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■ The Reaction between Benzotriazole and Diarylnitrileimines
Revannuru Venkatachaliah Venkataratham and José Elguero*
*Instituto de Química Médica, C. S. I. C., Calle Juan de Cierva, 3, 28006 Madrid, Spain
Abstract
The reaction between benzotriazole and diarylnitrileimines yielded the arylhydrazones of 1- and 2-benzotriazole. The structures were established through detailed studies by 1H and 13C nmr spectroscopies.
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■ Synthesis of Vinca Alkaloids and Related Compounds. XXV. A New Approach to (±)-Tetrahydrosecodin-17-ol, (±)-Tetrahydrosecodine, (±)-Vincadifformine, (±)-ψ-Vincadifformine and (±)-Minovine
György Kalaus, Miklós Kiss, Mária Kajtár-Peredy, János Brick, Lajos Szabó, and Csaba Szántay*
*Institute for Organic Chemistry, Technical University Budapest, H-1521 Budapest, P.O. Box 91Gellért tér 4, Hungary
Abstract
Starting from 1 the syntheses of the title compounds were achieved using Polonovski reaction of 7 as the key step.
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■ Diels-Alder Reaction of 1,2,3-Triazine with Enamines
Teruyo Sugita,* Junko Koyama, Kiyoshi Tagahara, and Yukio Suzuta
*Kobe Women’s College of Pharmacy, Motoyamakita, Higashinad, Kobe, Hyogo 658, Japan
Abstract
1,2,3-Triazine has been shown to react with enamines to afford products of [4+2]cycloaddition reaction. Loss of nitrogen and pyrrolidine from the initial bicycloadducts afford 2,3-disubstituted pyridines.
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■ The Synthesis of C-13 Labeled Vitamin E, [6’-13C]all-rac-α-Tocopherol
Shiro Urano,* Ikuo Otani, and Mitsuyoshi Matsuo
*Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo 173-, Japan
Abstract
Vitamin E with a 13C-labeled isoprenoid side chain, [6’-13C]all-rac-α-tocopherol (1) was synthesized using 6-methoxymethoxy-2,5,7,8-tetramethyl-2-[(E)-4-methyl-5-(thiazolin-2-yl)thio-3-penten-1-yl]chroman (6) as a key intermediate and ethyl [1-13C]bromoacetate as a 13C source. The overall yield of 1 based on ethyl [1-13C]bromoacetate was 19.2%.
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■ Stereoselective Synthesis and Thermal Behavior of (Z)-Epoxyhexenynes: A Sinple and General Route to 2-Vinylfurans
Wolfgang Eberbach* and Joachim Roser
*Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, D-7800, Germany
Abstract
An efficient approach for the synthesis of 2,3-disubstituted furans (2a-j/3a-j) is described by using the thermally induced rearrangement of epoxyhexenynes (1a-j) which are prepared by stereoselective synthesis of the (Z)-pentenynals 10 and subsequent Darzens reaction.
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■ One Pot Synthesis of Quinazoline Derivatives by Use of Palladium Catalyzed Carbonylation
Miwako Mori, Hiromi Kobayashi, Masaya Kimura, and Yoshio Ban*
*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan
Abstract
One pot synthesis of quinazoline derivatives from a mixture of o-iodoaniline 1a and five membered lactams or N-acyl-o-iodoaniline derivatives, 1b and 1c, and primary amines was effected through the palladium-catalyzed insertion of carbon monoxide.
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■ Studies on as-Triazine Derivatives. VI. Introduction of Aryl Groups to the 5-Position of 1,2,4-Triazines
Shoetsu Konno, Mataichi Sagi, Yasuko Yuki, and Hiroshi Yamanaka*
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
1,2,4-Triazine derivatives passessing different aryl groups at the 5- and 6-positions were synthesized by the addition of arylmagnesium bromides (Ar’MgBr) to 6-aryl(Ar)-3-methyl-1,2,4-triazines with the free 5-position, and subsequent methyl-1,2,4-triazines with the free 5-positron, and subsequent oxidation of the resulting 2,5-dihydro intermediates. The synthesis of 6-aryl-3-methyl-1,2,4-triazines is also described.
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■ A Facile Synthesis of the Substituted Tetrahydronapthalenes by the Banzo-Peterson Reaction
Seiichi Takano,* Shizuo Otaki, and Kunio Ogasawara
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
Thermal treatment of the o-hydroxymethylbenzylsilanes with an excess maleic anhydride or 2,3-dichloromaleic anhydride afforded the corresponding substituted tetrahydronaphthalenes stereoselectively in satisfactory yields presumably via the o-quinodimethane intermediates generated by the benzo-Peterson reaction.
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■ Organic Synthesis Using PTC-1: Reactions of Oxybis(bromomethane) with Diols under Liquid-liquid Phase Transfer Conditions
Paramjit Singh* and Geeta Arora
*Department of Chemistry, Guru Nanak Dev University, Amritsar -143 005, Punjab, India
Abstract
Reaction of oxybis(bromomethane) with 1,2-dihydroxybenzene gives 1,3,5-benzotrioxepin and dibenzo[f,m][1,3,5,8,10,12]hexaoxacyclotetradecin1 but 1,3-and 1,4-dihydroxybenzene derivatives furnish only polymeric products. 1,2-Bis(2-hydroxyethoxy) benezene with oxybis(bromomethane) 1 gives macrocyclics 6 and 7.
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■ Syntheses and Transformations of 4-Amino-2-methylthio- and 4-Amino-2-methoxypyrimidine-5-carboxamide Oximes
Branko Stanovnik,* Uros Urleb, and Miha Tisler
*Department of Chemistry, E. Kardelj University, Murnikova 6, 61000 Ljubljana, Slovenia
Abstract
4-Amino-5-cyano-2-methylthio- (1) and 4-amino-5-cyano-2-methoxypyrimidine (13) were transformed with hydroxylamine into the corresponding pyrimidine-5-carboxamide oximes (2 and 14). Acylation and carbethoxylation under mild conditions produced O-substituted carboxamide oximes (3, 7, 9, 15, 18, and 19), while under more vigorous conditions cyclization occurred producing 5-(1,2,4-oxadiazolyl)-pyrimidines (4, 6, 8, and 16).
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■ Amathamide Alkaloids from the Marine Bryozoan Amathia wilsoni Kirkpatrick
Adrian J. Blackman* and David J. Matthews
*Department of Chemistry, University of Tasmania, GPO Box 252C Hobart, Tasmania, 7001, Australia
Abstract
Two brominated proline-derived alkaloids named amathamide A and B have been isolated from the marine bryozoan Amathia wilsoni.
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■ Compounds of Broussonetia papyrifera (L.) Vent. 2. Structures of Two New Isoprenylated Flavans, Kazinols A and B
Junko Ikuta (née Matsumoto), Yoshi Hano, and Taro Nomura*
*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan
Abstract
Two new isoprenylated flavans, named kazinols A (1) and B (2), were isolated from the benzene extract of the cortex of Broussonetia papyrifera (L.) Vent. (Japanese name “Kazinoki”, Moraceae). The structures of kazinols A and B were shown to be 1 and 2, respectively, on the basis of spectral evidence.
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■ Synthesis of Vinca Alkaloids and Related Compounds. XXVI. An Unusual Side-chain Elimination from Indole Nucleus
Mária Incze, Ferenc Sóti, Zsuzsanna Kardos-Balogh, and Csaba Szántay*
*Central Research Institute for Chemistry, Hungarian Academy of Sciences, H-1025 Budapest, Pusztaszeri ut 59-67, P.O.Box 17, Hungary
Abstract
Investigating the Hofmann reaction of quaternary salt 2 an unusual side-chain elimination from position 3 of the indole nucleus has been observed.
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■ Autoxidation of Nitrogen Heterocycles. 2. Kinetic Measurements of the Autoxidation of 2,5-Dimethylpyrrole
Bruce D. Beaver,* John V. Cooney, and John M. Watkins, Jr.
*Chemistry Division, Code 6181, Naval Research Laboratory, Washington, DC 20375-5000, U.S.A.
Abstract
The autoxidation of 2,5-dimethylpyrrole in dodecane is believed to proceed by a charge transfer mechanism. Kinetics measurements are presented which are consistent with this hypothesis.
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■ Cyclization of Dinitriles by Hydrogen Halides. 2. Hydrogen Chloride and Hydrogen Iodine
Pedro Victory* and Miquel Garriga
*Departmento de Química Orgánica, Instituto Químico de Sarriá, Universitat de Barcelona, 08028 Barcelona, Spain
Abstract
The cyclization reaction of the 6-cyanamino-5-cyano-3,4-dihydro-4-methyl-2-pyridone (1) with hydrogen chloride and hydrogen iodide is described. While the reaction with hydrogen chloride is regiospecific leading to the 4-amino-2-chloro-5,6-dihydro-5-methylpyrido[2,3-d]pyrimidin-7(8H)-one (4), hydrogen iodide affords two possible isomers. The 2-amino-4-iodo substituted one (5) is prepared selectively at low temperature whereas higher temperatures lead to the 4-amino-2-iodo substituted compound (6). Reductive deiodination takes place with excess of hydrogen iodide at high temperature but only in position 2.
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■ A Synthesis of trans- and cis-Caronaldehydes
Seiichi Takano,* Nobuaki Sato, Masashi Akiyama, and Kunio Ogasawara
*Pharmaceutical Institute,Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
A preparation of trans- and cis-caronaldehyde derivatives is described by employing iodolactonization reaction as a key step. Investigation is also carried out to establish an asymmetric synthesis by employing the same methodology which allows diastereoselective formation of optically active intermediates in both enantiomeric forms from a single precursor though the degree of asymmetric induction is found to be less satisfactory.
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■ New Alkaloids from Delphinium staphisagria Linné
S. William Pelletier* and Mohamed M. Badawi
*Department of Chemistry, Institute for Natural Products Research, The University of Georgia, Chemistry Building, Athens, Georgia 30602-2556, U.S.A.
Abstract
Three new C19-diterpenoid alkaloids, delstaphisine (3), delstaphisagrine (4) and delstaphisagnine (5) have been isolated from the seeds of Delphinium staphisagria by a combination of grodient pH extractions and chromatographic techniques, including vacum liquid chromatography (vlc) and centrifugally accelerated, radial, thin-layer chromatography (“Chromatotron”). The structures have been detemined with the aid of proton and carbon-13 nmr spectroscopy. Delstaphisine (3) is the first reported aconitine-type, C19-diterpenoid alkaloid bearing a C(16)-hydroxyl group.
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■ Acrylonitrile Photoaddition on 1-Benzyl-1,4-dihydronicotinamide
Giorgio Adembri,* Donato Donati, Stefania Fusi, and Fabio Ponticelli
*Istituto di Chimica Organica, Università di Siena, Pian dei Mantellini 44, 53100 Siena, Italy
Abstract
Stereospecific acrylonitrile photoaddition on enamide moiety of 1-benzyl-1,4-dihydronicotinamide I followed by catalytic hydrogenation affords 2-benzyl-7- and -8-cyano-2-azabicyclo[4.2.0]octane-6-carboxamide IV and V. Both compounds show a trans configuration between cyano and carbamoyl groups.
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■ A Total Syntehsis of (±)-Agroclavine-I. A New C/D-cis-8-Ergolene Alkaloid
Toshiko Kiguchi, Chiyomi Hashimoto, and Ichiya Ninomiya*
*Kobe Women’s College of Pharmacy, Motoyamakita, Higashinad, Kobe, Hyogo 658, Japan
Abstract
A new total synthesis of (±)-agroclavine-I was described.
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■ Synthesis by Phase Transfer Catalysis of N-Benzyl, N-Diphenylmethyl and N-Triphenylmethyl Azoles and Benzazoles: Proton NMR and Chromatographic Data as a Tool for Identification
Rosa Ma. Claramunt,* José Elguero, and Rafael Garceran
*Química Orgánica, Universidad Nacional de Educacíon a Distancia, Cantoblanco, 28049-Madrid, Spain
Abstract
Pyrazole, imidazole, 1,2,4-triazole, indazole and benzotriazole were alkylated under phase transfer catalysis (PTC) with benzyl-, diphenylmethyl- and trityl chloride. Alkylation occurred only at the ring nitrogen atoms of the heterocycle, except for indazole in which substitution took also place at position 3. A systematic study of the N- and C-substituted derivatives by proton NMR and chromatographic techniques has been done.
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■ A Diastereoselective Synthesis of 7-Arylpyrimido[6,1-a]iaoquinolines through N-Acyliminium Ion Cyclization
Shinzo Kano* and Yoko Yuasa
*School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
Abstract
Reduction of ureas (4 and 9a) with diisobutylaluminum hydride, followed by cyclization with formic acid gave the corresponding 1- and 7-substituted pyrimido[6,1-a]isoquinolines (5 and 10a), respectively, with diastereoselectivity. In a similar fashion, 7-aryl-1-methyl analogues (10b,c) were obtained from ureas (9b,c) accompanied by the formation of uncyclized formates (11a,b), respectively.
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■ Synthesis of (±)-Lupinine and (±)-Epi-lupinine using Regioselective Alkylation of Functionalized 3-Sulfolene
Takashi Nomoto and Hiroaki Takayama*
*Faculty of Pharmaceutical Sciences, Teikyo University, 1091-1 Suarashi, Sagamiko-machi, Tsukui-gun, Kanagawa 199-0195, Japan
Abstract
The regioselective alkylation of 3-(N,N-dimethylaminomethyl)-3-sulfolene was applied to the synthesis of quinolizidine alkaloids, (±)-lupinine and (±)-epi-lupinine.
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■ Photodegradation of Pesticides: Photolysis of 2-Mercaptobnzothiaozle and 2-Mercaptobenzimidazole
Cyril Párkányi and Abdou O. Abdelhamid*
*Department of Chemistry, The University of Texas at El Paso, El Paso, Texas 79968-0513, U.S.A.
Abstract
Upon their application, organic pesticides are usually exposed to light under a variety of conditions. After some time, most of them undergo photodecomposition, especially in solution, and give degradation products with properties different from those of the original compounds. Thus, studies of the photochemistry of pesticides under controlled laboratory conditions are of interest. As an example, model studies of the photodegradation of 2-mercaptobenzothiazole (1, used as fungicide, bactericide, and disinfectant) and of the Π-isoelectronic, biologically active 2-mercaptobenzimidazole (2) have been carried out. Uv irradiation of 1 in the presence of air oxygen in a pyrex flask yielded bis-(2-benzothiazolyl) disulfide when dry benzene or toluene were used as the reaction medium. With solutions of 1 in methanol, ethanol, or acetonitrile, the corresponding bis-(2-benzothiazolyl) disulfone was obtained as the intermediate, with benzothiazole sulfate as the final reaction product. Similarly, photolysis of 2 in methanol, ethanol, or acetonitrile yielded bis-(2-benzimidazolyl) disulfone and benzimidazole sulfate as the final product.
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■ Transformation of 2,3,9,10-Tetraoxygenated Protoberberine Alkaloids into 2,3,10,11-Tetraxygenated Protoberberine Alkaloids
Miyoji Hanaoka,* Mari Marutani, Kazuhiro Saitoh, and Chisato Mukai
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
2,3,10,11-Tetraoxygenated tetrahydroprotoberberine (6) were synthesized from the corresponding 2,3,9,10-tetraoxygenated protoberberine alkaloids (1) through oxidative C8-C8a bond cleavage, photocyclization, and deoxygenation.
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■ Steroids and Related Studies. Part 73. Steroidal[3,2-c]-1’,2’,5’-oxadiazoles
Harkishan Singh,* Mange Ram Yadav, Sat Paul Garg, Rakesh K. Sharma, and Dharam Paul
*Department of Pharmaceutical Sciences, Panjab University, Chandigarh 160014, India
Abstract
A procedure for the synthesis of steroidal[3,4-c]-1’,2’,5’-oxadiazoles has been developed. The sequence consists of converting 4-en-3-ones to 4,5-oxido-3-ones, rearrangement of the oxiranes to 4-hydroxy-4-en-3-one system, which forms the 3,4-dioxime, changing to the oxadiazole on treatment with alkali. The synthesis of 5-epimeric 5δ-cholestano[3,4-c]-1’,2’,5’-oxadiazoles 5 is described. Synthesis of 17-hydroxy-17α-methyl-5δ-androstano[3,4-c]-1’,2’,5’-oxadiazoles 2, first attempted by starting with methyltestosterone, has been achieved from oxymesterone 9. The 5α- (HS-805) and 5β- (HS-804) isomers have been separated. HS-805 has been found to be less active than furazabol 1 which is the respective [2,3-c]-1’,2’,5’-oxadiazole.