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. 29, No. 4, 1989
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■ Mass Spectrometric Evidence for Formation of the 2-Carbonyl-2H-indole Intermadiate
Mitsuo Akiba,* Takanobu Maejima, Toyozo Takada, and Yasuo Shida
*School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
Abstract
The mass spectra of indole-2-carboxylic acid derivatives were investigated. In particular, indole-2-carboxylic acids with good leaving groups were noted to undergo the thermal rearrangement in the ion source of the mass spectrometer to form a ketene and a ketene dimer.
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■ A One Step Transformation of 4α,5β-Epoxygermacranolide into Pseudoguaianolide
Alfredo Ortega and Emma Maldonado
*Facultad de Química, Universidad Nacional Autónama de México, Circuito Exterior, Ciudad Universitaria, Coyoacán 04510, Mexico
Abstract
Adsorption of the germacranolide 4α,5β-epoxyinunolide (1) on bentonitic earth provided the guaianolide inuviscolide (2) and 4α,5α-epoxy-10α,14H-inuviscolide (3) as well as the pseudoguaianolide 8-epiconfertin (4). This one step transformation represents the first biomimetic conversion of a germacranolide into a pseudoguaianolide, substantiating previously proposed biogenetic pathways.
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■ Enantioselective Total Syntheses of (4R,6R)-(+)-4-Hydroxy-6-pentylvalerolactone, ex Cephalosporium recifei, and of (6R)-(—)-Massoialactone
Frank Bennett, David W. Knight,* and Garry Fenton
*School of Chemistry, University of Nottingham, Nottingham NG7 2RD, U.K.
Abstract
Total Syntheses of (4R,6R)-(+)-4-hydroxy-6-pentylvalerolactone (6) and (6R)-4-(-)-massoialactone (7) have been achieved, starting from the yeast reduction product methyl (3R)-3-hydroxyhexenoate (1).
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■ New Reactions of Thallium Compounds: A Simple Synthesis of 4- and 7-Substituted Indoles Bearing a Nitro or an Azido Group
Masanori Somei,* Fumio Yamada, Hirokazu Hamada, and Toshio Kawasaki
*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
New reactions for converting thallium compounds to nitro and azido compounds are elaborated. Applying these reactions, 4-nitroindole-3-carboxaldehyde and 1-acetyl-2,3-dihydro-7-nitroindole are now readily available in one pot reaction from indole-3-carboxaldehyde and 1-acetyl-2,3-dihydroindole, respectively. 4-Azidoindole-3-carboxaldehyde and 1-acetyl-7-azido-2,3-dihydroindole are similarly produced. Preparation of methyl 4-nitroindole-3-carboxylate is also reported.
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■ Strained Heterocyclic Systems. 16. 1-Azatriotycene
J. Hodge Markgraf,* Kathryn J. Leonard, Marlene E. Morrison, and Christopher R. Myers
*Department of Chemistry, Williams College, 47 Lab Campus Drive, Williamstown, MA 01267, U.S.A.
Abstract
The first synthesis of 1-azatriptycene (1) was accomplished in four steps from 2-naphtnylamine. Its pkα was determined by potentiometric titration and compared to that of diphenyl-2-pyridylmethane. The seven-fold decrease in the basicity of 1 was attributed to ring strain effects.
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■ Si-Thall Reaction, a Method for Cross Coupling Silicon Compounds with Thallium Compounds
Masanori Somei,* Toshiharu Ohta, Junko Shinoda, and Yoshimi Somada
*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
A new palladium catalyzed regioselective cross coupling reaction between thallium compounds and silicon containing compounds is developed.
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■ Monofunctionalization Study of Furan-2,5-dicarboxaldehyde. Conformational Analysis and Model Reactions
Irmina Hernández-Fuentes,* Cristina Abradelo, Carmen Domínguez, Aurelio G. Csáky, Joaquín Plumet,* Carlos Cativiela, José Antoine Mayoral, Antonio Gaset, and Luc Rigal
*Departamento de Química Orgánica I., Facultad de Química, Universidad Complutense de Madrid, Ciudad Universitaria, E-28040 Madrid, Spain
Abstract
The possible monofunctionalization of furan-2,5-dicarboxaldehyde is verified by means of several model reactions. On the other hand conformational analysis of FDC is analized by a combined experimental dipole moment determination-theoretical MNDO calculation.
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■ Synthesis of the Enantiomeric Polyether Fragment of Tetranomycin
Kozo Hori, Keiichi Nomura, and Eiichi Yoshii*
*Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama, Toyama 930-0194, Japan
Abstract
The absolute stereochemistry of tetronomycin (2), a novel acyltetronic acid ionophore, was confirmed by comparison of the degradation product 3 with the synthetic enantiomer 9 derived from L-rhamnose. The enantiomer 18 of the polyether subunit of 2 was synthesized by coupling 9 with tetrahydropyran portion 15 prepared from D-glucose.
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■ Synthesis of 4-Carbosubstituted Isoxazole Derivatives
Angel Alberola, Antonio Pérez Serrano, Ma Teresa Rodríguez Rodríguez, and Carmen Orozco
*Deparamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, 47005 Valladolid, Spain
Abstract
3,5-Disubstituted 4-lithioisoxazoles were synthesized selectively and in good yields by exchange between 4-bromoisoxazoles and n-BuLi as it is proved carboxylation. Reactions of 3,5-disubstituted 4-lithioisoxazoles with saturated or α,β-unsaturated carbonyl compounds, esters, nitriles and amidea allow the introduction of carbon-chains with different functionality at C-4.
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■ Photochemistry of β-(2-Furyl) Substituted o-Divinylbenzenes
Marija Sindler-Kulyk,* Lidija Spoljaric, and Zeljko Marinic
*Organic Chemistry Department, Faculty of Technology, University of Zagreb, Marulicev trg 20, 41000 Zagreb, Croatia
Abstract
Irradiation of the benzene solution of 1-(2-vinylphenyl)-2-(2-furyl)ethenes (7) resulted in the formation of furo[3,2-b]-6,7-benzobicyclo[3.2.1]octa-2,6-dienes (10) as the main product. The structure of the products was determined by spectroscopic data.
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■ Constituents of Brosimopsis oblongifolia. 4. Structures of Two New Diels-Alder Type Adducts, Brosimone B and Brosimone D
Irene Messana,* Franco Ferrari, Josè Francisco de Mello, and Maria do Carmo Mesquita de Araujo
*Instituto di Chimica, Università Cattolica del Sacro Cuore, L. F. Vito 1, 00168 Roma, Italy
Abstract
Brosimones B and D, two new Diels-Alder type adducts, were isolated from the acetone extract of the roots of Brosimopsis oblonqifolia. The structures of brosimones D and B were shown to be 1 and 2, respectively, on the basis of spectral data.
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■ Synthesis and Reactions of Isoquinolines IV. Reactions of 3-Chloroisoquinoline-4-carbaldehydes
Elmar Konz and Wolfgang Rüger*
*Entwicklungsgruppe Synthese und SBU Antiinfektiva, Allgemeine Pharma Forschung, Hoechst AG, Postfach 800320, D-65926 Frankfurt, Main 80, Germany
Abstract
3-Chloroisoquinoline-4-carbaldhydes 2 are versatile intermediates for various functional manipulations as e.g. oxidation or reduction of the formly group or nucleophilic substitution of the chloro substituent leading to products with interesting pharmacological properties.
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■ Synthesis and Reactions of Isoquinoline Derivatives V. Synthesis and Reactions of 3-Chiloroisoquinoline-4-carboxylic Acids
Wilhelm Bartmann, Elmar Konz, and Wolfgang Rüger*
*Entwicklungsgruppe Synthese und SBU Antiinfektiva, Allgemeine Pharma Forschung, Hoechst AG, Postfach 800320, D-65926 Frankfurt, Main 80, Germany
Abstract
Derivatives of 3-chloroisoquinoline-4-carboxylic acid are easily accessible by potassium permanganate oxidation of the corresponding aldehydes. Conditions have been developed for selective reduction, substitution and decarboxylation reactions leading to 3-substituted isoquinoline derivatives with, interesting pharmacological properties.
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■ The Behaviour of 4-Benzoyl-2-azetidinones with Bases. Regioselectivity in Their Alkylation Reactions
Benito Alcaide, Gema Dominguez, Angel Martín-Domenech, Inmaculade Martín, Carlos Cativiela, José A. Mayoral, and Joaquín Plumet*
*Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Extremadura, Avenida de Elvas s/n, 06071-Badajoz, Spain
Abstract
4-Benzoyl-2-azetidinones react with alkyl halides in the presence of bases in a regioselective fashion depending on the substitution pattern in the β-lactam ring and on the alkylating agent. In this way, different kinds of products derived from C- and O-alkylation of 4-benzoyl-β-lactams, 10, 11, 14, and 16, as well as products derived from ring expansion of the β-lactam moiety and subsequent O-alkylation, 15, have been obtained. In addition, the reaction course for the isomerization of cis-4-benzoyl-2-azetidinones 1 has been elucidated on the basis of experimental data and MNDO calculations.
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■ Isolation of Meliacin CInnamates from the Root Bark of Azadiracha indica A. Juss (Meliaceae)
Iffat Ara, Bina Shaheen Siddiqui, Shaheen Faizi, and Salimuzzaman Siddiqui
*H. E. J. Postgraduate Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan
Abstract
A new tetranortriterpenoid named as nimbolicin has been isolated from the neutral fraction of root bark of Azadirachta indica A.Juss (neem) besides nimbolin B previously reported from the trunk wood. The structure elucidation of nimbolicin through chemical and spectroscopic methods along with the hitherto unreported 13C-nmr and 2D spectral studies (NOESY, COSY, heterocosy) of nimbolin B form the subject of present communication.
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■ Heterocyclic Photorearrangements - Photoinduced Rearrangements of Some 3-Aroylamino-5-methyl-1,2,4-oxadiazoles
Silvestre Buscemi and Nicolò Vivona*
*Dipartimento di Chimica Organica, Università digli Studi di Palermo, Via Archirafi 20 90123 Palermo, Italy
Abstract
The photochemical behaviour of some 3-aroylamino-5-methyl-1,2,4-oxadiazoles in methanol at 254 nm has been studied. On irradiation, the oxadiazoles underwent a photorearrangement reaction to the corresponding 2-acetylaminoquinazolin-4-one derivatives.
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■ Synthesis and Reactivity of 2-(1,3-Dithian-2-yl)indoles II. Synthesis of 2-Acylindole Derivatives
M.-Lluïsa Bennasar, Antoni Torrens, Mario Rubiralta, Joan Bosch, David S. Grierson, and Henri-Phillippe Husson
*Laboratory of Organic Chemistry, Faculty of Pharmacy, University of Barcelona, Av. de Joan XXIII, s/n, 08028 Barcelona, Spain
Abstract
Some reactions of the anions (4b and 4c) derived from indole dithianes 3b and 3c respectively, towards aldehydes, ketones, α,β-unsaturated ketones, alkyl halides, and epoxides are reported.
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■ Synthesis and Reactions of Biginelli-Compounds, Part II. Nitration of 6-Methyl-2-oxo-1,2,3,4-tetrahydro-5-pyrimidinecarboxylates
C. Oliver Kappe* and Urlike G. Wagner
*Institute for Organic Chemistry, Karl-Franzens-University Graz, Heinrichstrasse. 28, A-8010 Graz, Austria
Abstract
The nitration of tetrahydro-5-pyrimidinecarboxylates (Biginelli-Compounds2) 1 and 4 does not yield 5-nitrodihydro-5-pyrimidinecarboxylic acids 2a,b as assumed earlier, but affords the corresponding 5-nitro-4-nitromethylidene-hexahydro-5-pyrimidinecarboxylates 3. Single-crystal X-ray studies show that 3a exists in the intramolecularly H-bondend (Z)-configurated form, whereas nmr spectra indicate that 3a can exist in both (Z)-and (E)-configurated forms, depending on the solvent used.
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■ Preparation of Alkyl-Substituted Indoles in the Benzene Portion. Part 1
Hideaki Muratake and Mitsutaka Natsume*
*Research Foundation Itsuu Laboratory, 2-28-10 Tamagawa, Setagaya-ku, Tokyo 158, Japan
Abstract
Variously alkylated 4-(1-methoxycarbonyl-2-pyrroly1)-2-butenals (11 and 12) were cyclized to 1-methoxycarbonylindoles (14) having alkyl substituents in the benzene portion, simply by refluxing in benzene solution with a catalytic amount of p-TsOH. A natural product, 7-(3-methyl-2-butenyl)indole (27) was synthesized by this technique, whereas the corresponding 6-isomer (28), also a natural product, was obtained by treatment of 32 with TMSOTf.
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■ Preparation of Alkyl-Substituted Indoles in the Benzene Portion. Part 2
Hideaki Muratake and Mitsutaka Natsume*
*Research Foundation Itsuu Laboratory, 2-28-10 Tamagawa, Setagaya-ku, Tokyo 158, Japan
Abstract
General Procedure for synthesizing alkylindoles (14) was developed by cyclization of 12 in i-PrOH using H2SO4 as a catalyst to 1-tosylindoles (13), whose protecting group was reductively cleaved with Mg in MeOH. 7-t-Alkylindoles (23 and 24) were synthesized by removal of the tosyl group of 26 and 35 in advance, followed by treatment of the resulting 34 and 36 with p-TsOH in refluxing C6H6.
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■ Synthesis of 1,7-Dideaza-2’-deoxyadenosine and Related Pyrrolo[2,3-b]pyridine 2’-Deoxy-β-D-ribonucleosides: Stereoselective Phase-Transfer Glycpsylation via the Nucleobase Anion
F. Seela* and R. Gumbiowski
*Laboratorium für Organische und Bioorganische, Institut für Chemie, Universität Osnabrück, Barbarastr. 7, D-4500 Osnabrück, Germany
Abstract
The synthesis of 1,7-dideaza-2’-deoxyadenosine (1) and related pyrrolo[2,3-b]pyridine 2’-deoxy-β-D-ribofuranosides is described. Glycosylation of the anions of the pyrrolo[2,3-b]pyridines 5a or 5b with 2-deoxy-3,5-di-O-(p-toluoyl)-α-D-erythro-pentofuranosyl chloride (6) has been carried out under phase-transfer conditions (MeCN, solid KOH, TDA-1, 25°C) and was complete within less than 15 min. The reaction was stereoselective and β-nucleosides were formed exclusively. The position of glycosylation as well as the anomeric configuration were assigned by NOE difference spectroscopy. Compound 1 was extremely stable against acid or base and was not deaminated by adenosine deaminase.
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■ Two New Phenolic Compounds, Kuwanols C and D, from the Root Bark of a Mulberry Tree Redifferentiated from the Callus Tissues
Yoshio Hano, Shinkichi Suzuki, Taro Nomura,* and Shinichi Ueda
*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan
Abstract
A new isoprenoid-substituted flavanone, kuwanol C, and a new isoprenoid-substituted chalcone, kuwanol D, were isolated from the root bark of a mulberry tree redifferentiated from the callus tissues along with eight known phenolic compounds. On the basis of spectral evidence, structures of kuwanols C and D were shown to be 1 and 2, respectively.
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■ Polymerization and/or Rearrangement Reactions of Acronycine and Related Compounds
Shinji Funayama and Geoffrey A. Cordell*
*Department of Medicinal Chemistry, College of Pharmacy, University of Illinois at Chicago, P.O.Box 6998, Chicago, IL 60680, U.S.A.
Abstract
By treating acronycine or noracronycine with methanolic hydrochloric acid, several oligomers were obtained, including compounds possessing a rearranged partial structure. We have also succeeded in the selective syntheses of monomers and/or oligomers of noracronycine and related compounds by altering the reaction condition(s). Further, polymerization and/or rearrangement reaction mechanisms were examined by the combination of the reactions using D-substituted reagents and 1H-nmr spectroscopic analysis.