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. 55, No. 1, 2001
Published online:
■ Synthesis of Apicidin
Wataru Kuriyama and Takeshi Kitahara*
*Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
Abstract
Tetrapeptide containing L-2-amino-8-protected hydroxydecanoic acid, L-N-O-methyltryptophan, L-isoleucine and D-pipecolinic acid was cyclized with pentafluorophenyl diphenylphosphinate. The cyclic tetrapeptide was deprotected and oxidized to apicidin [cyclo-(N-O-methyl-L-Trp-L-Ile-D-Pip-L-2-amino-8-oxodecanoyl)].
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■ Base-promoted Rearrangement of N-Tosyl-2,3-exo-aziridino[2,3]norbornane
Odón Arjona, Roberto Menchaca, and Joaquín Plumet*
*Departamento de Química Orgánica, Facultad de Química., Universidad Complutense de Madridas, Ciudad Universitaria, E-28040 Madrid, Spain
Abstract
The first experimental evidence of the generation of an imino carbene from the tittle compound is reported.
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■ Stereoselectivity in the Darzens Condensation of Substituted Cyclohexanones with (-)-8-Phenylmenthyl α-Chloroacetate
Yoshihiro Shinohara, Yuko Ohba, Ryukichi Takagi, Satoshi Kojima, and Katsuo Ohkata*
*Department of Chemistry, Graduate School of Sciencea, Hiroshima University, 1-3-1 Kagamiyama, Higashi-hiroshima, Hiroshima 739-8526, Japan
Abstract
The Darzens condensation of 4-monosubstituted and cis-3,5-dimethyl-cyclohexanones with (-)-8-phenylmenthyl α-chloroacetate proceeded to give mixtures of trans- and cis-glycidic esters with high enolate face selectivity (>95% de). The presence of axial methyl substituents at the 3 and 5 position lead to decrease in enolate face selectivity. The configuration of the major products was determined by NMR, derivation, and/or X-Ray crystallographic analysis.
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■ Absolute Structures of 3-Hydroxy-2-prenylflavanones with an Ether Linkage between the 2’- and 3-Positions from Moraceous Plants
Ya-Qin Shi, Toshio Fukai, Masaru Ochiai, and Taro Nomura*
*School of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan
Abstract
Absolute configurations at C-2 and C-3 of eight sanggenon-type flavanones (3-hydroxy-2-prenylflavanones with an ether linkage between the C-2’ and C-3 positions, i.e., sanggenons A, C, L, and M, sanggenols F, and G, and soroceins D and F.) were determined as (2R,3S)-configurations by chemical and spectroscopic methods.
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■ 13C NMR Spectral Assignment of 5-Hydroxy-1,5-imino-3-benzazocin-4,7,10-trione Derivatives: The Revised Structure of Renieramycin H
Naoki Saito,* Haruyuki Sakai, Khanit Suwanborirux, Sunibhond Pummangura, and Akinori Kubo*
*Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan
Abstract
13C NMR assignments of the ABC ring model compounds of saframycin H with the proposed structure were performed using a two-dimensional 1H detected heteronuclear multiple-bond correlation (HMBC) experiment. The structure of renieramycin H was reassigned with the revised structure.
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■ Tetrameric and Pentameric Ellagitannins from Monochaetum multiflorum
José H. Isaza M., Hideyuki Ito, and Takashi Yoshida*
*Faculty of Pharmaceutical Science, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan
Abstract
Two new hydrolyzable tannins, nobotanin S (1) and melastoflorin A (2), were isolated from the leaves of Monochaetum multiflorum, and their structures were characterized as tetrameric and pentameric ellagitannins based on detailed NMR analyses using 2D-NMR techniques and chemical evidence. Melastoflorin A (pentamer) was notably the biggest molecule among numerous hydrolyzable tannins.
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■ Synthesis of 2,2’-Biquinolines from o-Isocyanostyrenes
Kazuhiro Kobayashi,* Junpei Yonemori, Akihiro Matsunaga, Taichi Kitamura, Miyuki Tanmatsu, Osamu Morikawa, and Hisatoshi Konishi
*Department of Materials Science, Faculty of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan
Abstract
The heating of o-isocyanostyrenes (1) in diglyme at reflux temperature for 2 h afforded the corresponding 2,2’-biquinolines (2) via a coupling/electrocyclic reaction in fair-to-good yields.
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■ Synthesis of Chiral Azacrown Ethers Derived from α-D-Glucose and Their Catalytic Properties on the Asymmetric Michael Addition
Toshiyuki Itoh* and Shohei Shirakami
*Department of Chemistry, Faculty of Education, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan
Abstract
Three types of chiral azacrown ethers have been synthesized from (+)-(4,6-O-benzylidene)-O-methyl-α-D-glucopyranoside and their catalytic properties for the asymmetric Michael addition have been investigated; enantioselectivity switching which is dependent on the azacrown ether catalysts has been achieved.
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■ Preparation of New Imidacloprid Analogues
Lajos Novák,* Gábor Hornyánszky, Imre Király, János Rohály, Pál Kolonits, and Csaba Szántay
*Institute for Organic Chemistry, Budapest University o f Technical Economics, Gellért tér 4, H-1111 Budapest, Hungary
Abstract
A 3-step synthesis of the biologically active metabolites (2 and 3) of imidacloprid from aminoacetaldehyde diethyl acetal or ethylenediamine was developed. A series of new imidacloprid analogues were also prepared.
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■ Thermal Pathways for the Transfer of Amines, Including Nicotine, to the Gas Phase and Aerosols
Jay A Fournier,* John B. Paine III, Jeffrey I. Seeman,* Daniel W. Armstrong,* and Xianghong Chen
*Research Center, Philip Morris USA, P.O. Box 26853, Rcihmond, Vierginia 23261, U.S.A.
Abstract
Two pathways are proposed to explain the thermal transfer and/or pyrolysis of amines, a major class of plant constituents, to smoke. A crucial distinction is made based on the relative ease of evaporation of the amines compared to the ease of their pyrolytic decomposition. The temperatures required to transfer nicotine to the gas phase from nicotine and nicotine carboxylic acid salts, such as are found in tobacco, are lower than the decomposition temperatures of the nicotine ring system. Thermal gradient studies may better mimic the balance between evaporation and pyrolytic destruction of tobacco volatiles and semi-volatiles during smoking, as such thermolyses are performed by heating the substrate from ambient temperature to a higher temperature under a flow of gas.
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■ A Modified Procedure for the Synthesis of 5-Amino-3-arylisoxazoles and Their Reactions with Tetrasulfur Tetranitride Antimony(V) Chloride Complex (S4N4ÅESbCl5) : Novel Synthesis of 3-Aryl-1,2,5-thiadiazole-4-carboxamides
Yung Cheol Kong, Kyongtae Kim,* and Yung Ja Park
*School of Chemistry and Molecular Engineering, Seoul National University, Shillim-Dong, San 56-1, Seoul 151-742 , Korea
Abstract
Dropwise addition of α-bromo ketoximes to a solution of KCN in MeOH at room temperature gave 5-amino-3-arylisoxazoles in moderate to good yields. Treatment of the isoxazoles prepared with tetrasulfur tetranitride antimony (V) chloride complex (S4N4·SbCl5) in toluene at 100°C afforded novel 3-aryl-1,2,5-thiadiazole-4-carboxamides.
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■ Synthesis of a 2,3-Dimethoxyrotenonoid
Karla-Sue C. Marriott, Mario Anderson, and Yvette A. Jackson*
*Department of Chemistry, Mona Campus, University of the West Indies, Mona, Kingston 7, Jamaica, West Indies Jamaica
Abstract
Photo-Fries rearrangement of the o- fluoro ester of 3-hydroxy-6, 7-dimethoxycoumarin yielded the corresponding 3-hydroxy-4-(2-fluorobenzoyl)-coumarin which, in the presence of potassium carbonate, cyclised to the 2,3-dimethoxyrotenonoid. (1)-Benzofuran-(2, 3-c)–(6H, 12H)-(1)–benzoxepin- 6-ones underwent oxidation to the corresponding β-rotenonoids reluctantly.
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■ Reactions with N-Chlorosuccinimide of Various 5-Methylimidazo[1,2-a]pyridine Derivatives with an Electron-withdrawing Group Substituted at the 3-Position
Tomomi Ikemoto* and Mitsuhiro Wakimasu
*Chemical Development Laboratory, Takeda Chemical Industries, Ltd., 17-85 Jusohonmachi 2-chome, Yodogawa-ku, Osaka 532-8686, Japan
Abstract
Chlorination reactions using N-chlorosuccinimide (NCS) was investigated for various 5-methylimidazo[1,2-a]pyridine derivatives with an electron-withdrawing group substituted at the 3-position. These reactions showed different results, and by examining these, we proposed a reaction mechanism via the appropriate 3-halogenoimidazo[1,2-a]pyridium compounds as the reaction intermediates.
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■ Microwave-assisted Cyclocondesation under Solvent-free Conditions: Quinoxaline-2,3-dione
Ester Vázquez, Antonio de la Hoz, Nils Elander, Andrés Moreno, and Sharon Stone-Elander*
*Karolinska Pharamcy and Clinical Neurophysiology, Karolinska Hospital and Institute, S-17176 Stockholm, Sweden
Abstract
Use of monomodal microwave techniques together with solvent-free conditions in the condensation of 1,2-phenylenediamine with diethyl oxalate gives the quinoxaline-2,3-dione in good to high yields after 2-3 min. The method is simple, rapid and avoids prolonged heating with corrosive mineral acids.
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■ Synthesis and Transformations of Pyrido[4,3-d]pyrimidines with N-Heterocycles Moieties
A. Z. M. Shaifullah Chowdhury* and Yasuyuki Shibata
*Environmental Chemistry Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-0053, Japan
Abstract
ortho-Amino ester (1) was cyclized to fused pyrimidines by reacting with isocyanate, isothiocyanate, or dithioketal reagent. Thioxo compound (2a) was halogenated, methylated and subsequently displaced by amines. ortho-Amino ester (1) was also converted into directly tricyclic azolopyrido[4,3-d]pyrimidines (8-13).
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■ 1H- and 13C-NMR Investigations on σ-Adduct Formation of 1,2,4-Triazine 4-Oxides and 3-Chloro-6-phenyl-1,2,4-triazine with Liquid Ammonia and Alkylamines
Andrzej Rykowski,* Oleg N. Chupakhin, Dmitry N. Kozhevnikov, Valery N.Kozhevnikov, Vladimir L. Rusinov, and Henk C. Van der Plas
*Institute of Chemistry, University of Podlasie, ul. 3-go Maja 54, 08-110 Siedlce, Poland
Abstract
1H- and 13C-NMR spectra of the σ-adducts formed between 6-phenyl-1,2,4-triazine 4-oxide (1a), 3-ethyl-6-phenyl-1,2,4-triazine 4-oxide (1b) and liquid ammonia, methylamine or dimethylamine are described, together with 1H NMR spectra of 3-chloro-6-phenyl-1,2,4-triazine (7) in liquid ammonia. The results of the NMR study have shown that the carbon C-5 in 1a-b and 7 is the preferred site for nucleophilic attack by liquid ammonia and alkylamines at low temperatures (from -75° to -20°C). The s-adduct (5e) formed between 1a and dimethylamine at -75°C on heating to -20°C irreversibly converts to open-chain product (3a), via intermediary C-3 σ-adduct (6). The amination of 7 into 3-amino-6-phenyl-1,2,4-triazine (10) occurs via SN(AE) mechanism involving the isomerisation of the C-5 σ-adduct (8) into the C-3 σ-adduct (9) as confirmed by a 15N study with labeled liquid ammonia.
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■ Diastereoselective Ring-Expansion Reaction of Methanochromanone with Aldehydes: Formation of trans-Fused Tetrahydrofuro[2,3-b][1]benzopyranones and Their Isomerization
Yoshiaki Sugita,* Kazuyoshi Kawai, and Ichiro Yokoe
*Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japana
Abstract
In the presence of SnCl4, 2,3-dimethoxycarbonylmethanochromanone (4) was transformed into a zwitter-ion which easily reacted with aldehydes to give the trans-fused tetrahydrofuro[2,3-b][1]benzopyranones in good yields with high diastereoselectivity. cis-Fused furobenzopyranone derivatives were also obtained in good yields by isomerization of the trans isomers.
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■ Synthesis and Characterization of Functionalized Benzopentathiepins
Ryu Sato,* Tetsuya Ohyama, Takatomo Kawagoe, Masaru Baba, Shiduko Nakajo, Takeshi Kimura, and Satoshi Ogawa
*Department of Applied Chemistry, Faculty of Engineering, Iwate University, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan
Abstract
Four benzopentathiepins (12, 14, 16, and 18) having a functional group, such as aminoethyl, pyridyl, pyrimidinyl, and thienyl groups, respectively, on the benzene ring were synthesized from 3-substituted 1,2-benzenedithiol by sulfurization with elemental sulfur in the presence of ammonia. These benzopentathiepins were characterized in the light of interaction of the pentathiepin ring with the functional group.
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■ Reactions of 1,3-Dithiolane-2-thione and 1,3-Dithiole-2-thiones with 4-Phenyl-1,2,4-triazoline-3,5-dione(PTAD)
Juzo Nakayama,* Liting Zhao, Yoshiaki Sugihara, and Akihiko Ishii
*Department of Chemistry, Faculty of Science, Saitama University, Saitama, Saitama 338-8570, Japan
Abstract
1,3-Dithiolane-2-thione (1) and 1,3-dithiole-2-thione (18a) reacted with 4-phenyl-1,2,4-triazoline-3-dione (PTAD) to provide betaines, 4-phenyl-1-[2-(1,3-dithiolanio)]urazolide (8) (79%) and 4-phenyl-1-[2-(1,3-dithiolio)]-urazolide (19a) (73%), respectively. A mechanism, involving three-membered ring formation by an electrophilic 1,2-addition of the PTAD nitrogen atom to the C=S bond, is proposed. Discussion on the structure of 8 is made in some detail based on the spectroscopic data and X-Ray crystallographic analysis.
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■ Fluorenyl Participated Ring Transformation of Urazoles to Triazinanediones
Yong Gong,* Mark J. Bausch,* and Linhua Wang
*Department of Medicinal Chemistry, Aventis Pharmaceuticals, Route 202-206, P.O. Box 6800, Bridgewater, NJ 08807, U.S.A.
Abstract
Fluorenylation of 1,4-disubstituted urazole (1) with 9-bromofluorene affords corresponding fluorenylurazole (2) along with the rearrangement product triazinanedione (3). The ratio of two products is closely related to the acidity of starting urazole (1). Compound (2) can be transformed into 3 upon treated with potassium t-butoxide. A mechanism involving N-acylimine as ring opening intermediate is proposed. The dual roles of urazole anion (l-K) are discussed.
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■ An Unusual Cascade Reaction Yielding ortho-peri-Fused Thienopyridopyrimidines
Ulrich Sensfuss and Wolf-Dieter Habicher*
*Institut für Organische Chemie, Technische Universität Dresden. Mommsenstr. 13, D-01062 Dresden, Germany
Abstract
A cascade-like ring transformation of a thieno[2,3-d]pyridine derivative is reported and mechanistically explained. The product is a novel heterocyclic system consisting of a thiophene ring peri-fused with a pyrido[2,3-d]pyrimidine moiety. Various derivatives of the new ring system were prepared.
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■ Calixarenes Bearing Azaaromatic Moieties
Wanda Sliwa
*Institute of Chemistry and Environment Protection, Pedagogical University, al. Armii Krajowej 13/15, 42-201 Czestochowa, Poland
Abstract
The chemistry of calixarenes bearing azaaromatic moieties is reviewed. Calixarenes containing covalently and noncovalently bonded azaaromatic units are presented and their synthetic approaches along with complexing properties and catalytic activities are described.