Regular Issue

Vol. 63, No. 7, 2004

21 data found. 1 - 21 listed
Communication | Regular issue | Vol 63, No. 7, 2004, pp. 1531 - 1535
Published online: 11th May, 2004
DOI: 10.3987/COM-04-10065
Direct Conversion of 2-Acetamido-2-deoxysugars to 1,2-Oxazoline Derivatives by Dehydrative Cyclization in Water

Jun-ichi Kadokawa, Mitsumasa Mito, Satoshi Takahashi, Masato Noguchi, and Shin-ichiro Shoda*

*Department of Materials Chemistry, Graduate School of Engineering, Tohoku University, Sendai 980-8579, Japan


Sugar oxazoline derivatives were directly prepared by dehydrative cyclization of 2-acetamido-2-deoxysugars using a water-soluble carbodiimide in water. N-Acetyl-D-glucosamine, N-acetyl-D-galactosamine, and N,N’-diacetylchitobiose were converted to the corresponding 1,2-oxazoline derivatives in 37, 28, and 40 % yields, respectively.

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Communication | Regular issue | Vol 63, No. 7, 2004, pp. 1537 - 1540
Published online: 14th May, 2004
DOI: 10.3987/COM-04-10073
Synthesis and Characterization of Hexakis(4-pyridylethynyl)benzene and Hexakis(5-pyrimidylethynyl)benzene

Masakazu Ohkita,* Chihaya Adachi, Miki Kawano, and Takanori Suzuki

*Graduate School of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan


Two new members of snowflake-shaped carbon-rich molecules possessing nitrogen-heterocycles as functional end groups, hexakis(4-pyridylethynyl)benzene (1) and hexakis(5-pyrimidylethynyl)benzene (2), have been prepared by six-fold Sonogashira cross-coupling reaction of hexabromobenzene with 4-ethynylpyridine and 5-ethynylpyrimidine, respectively.

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Communication | Regular issue | Vol 63, No. 7, 2004, pp. 1541 - 1545
Published online: 18th May, 2004
DOI: 10.3987/COM-04-10088
Efficient Photochemical Oxetane Formation from 2-Pyrones and Benzophenones in the Solid State

Tetsuro Shimo, Ryoji Yamaguchi, Yuka Odo, and Kenichi Somekawa*

*Department of Applied Chemistry, Faculty of Engineering, Kagoshima University, Korimoto, Kagoshima 890, Japan


Solid-state photocycloaddition reactions of 2-pyrones (1, 4) with benzophenone derivatives (2a-c, f) afforded highly site- and regioselective oxetanes (3a, 3b, 3c, 3f, 5a, 5b, 5c, 5f) across the C5-C6 double bond in 1 or 4 via the triplet excited state of 2. The site- and regioselectivities were explained by MO calculations.

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Paper | Regular issue | Vol 63, No. 7, 2004, pp. 1547 - 1554
Published online: 23rd April, 2004
DOI: 10.3987/COM-04-10039
Characterization of the Oxidation Products of (-)-Epigallocatechin Gallate, a Bioactive Tea Polyphenol, on Incubation in Neutral Solution

Tsutomu Hatano,* Mami Hori, Miwako Kusuda, Takayo Ohyabu, Hideyuki Ito, and Takashi Yoshida

*Faculty of Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-Naka, Okayama 700-8530, Japan


(-)-Epigallocatechin gallate (EGCG) (1) changes rapidly into various products in neutral solution containing trace amounts of metal ions as catalysts. In addition to theasinensins A (2) and D (3), (-)-gallocatechin gallate (4), and gallic acid, five products were isolated from a reaction mixture resulting from the incubation of 1. MS and NMR spectroscopic analyses of the products revealed two monomeric [EGCG-MOx-M1 (5) and M2 (6)], and three dimeric [EGCG-MOx-D1 (7), D2 (8) and D3 (9)] structures.

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Paper | Regular issue | Vol 63, No. 7, 2004, pp. 1555 - 1561
Published online: 14th May, 2004
DOI: 10.3987/COM-04-10071
Facile Methods for Preparation Thiazolopyridine and Tetrahydrothiazolopyridine Derivatives

Noriyasu Haginoya,* Satoshi Komoriya, Ken Osanai, Toshiharu Yoshino, Tsutomu Nagata, Masatoshi Nagamochi, Ryo Muto, Mitsuhiro Yamaguchi, Takayasu Nagahara, and Hideyuki Kanno

*Medicinal Chemistry Research Laboratory, Daiichi Pharmaceutical Co., Ltd., 16-13, Kitakasai 1-chome, Edsogawa-ku, Tokyo 134, Japan


The improved routes to prepare tetrahydrothiazolo[5,4-c]pyridine-2-carboxylic acid lithium salts (2 and 3) were developed. Route A is consisted of the improved preparation of thiazolopyridine intermediates, and Route B is applicable for a large scale synthesis of tetrahydrothiazolo[5,4-c]pyridine-2-carboxylic acid derivatives. The methods we developed may serve as facile means for preparing thiazolopyridine and tetrahydrothiazolopyridine derivatives.

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Paper | Regular issue | Vol 63, No. 7, 2004, pp. 1563 - 1572
Published online: 27th April, 2004
DOI: 10.3987/COM-04-10077
Dendritic Cyclotriphosphazene Derivative with Hexaxis(alkylazobenzene) Substitution as Photo-sensitive Trigger

Makoto Takafuji, Tomohiro Shirosaki, Taisuke Yamada, Toshihiko Sakurai, Dzhamil Alekperov, Galina Popova, Takashi Sagawa, and Hirotaka Ihara*

*Faculty of Engineering, Kumamoto University, Kurokami 2-39-1, Kumamoto 860-8555, Japan


A dendritic cyclotriphosphazene derivative was synthesized by substitution with six alkylazobenzenes onto cyclotriphosphazene. Photo-induced trans-to-cis isomerization of the azobenzene moieties was discussed on each substituent. It was also investigated that the dendrimer acted as a photosensitive trigger for microenvironmental modification of chirally self-assembled organogels through the isomerization.

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Paper | Regular issue | Vol 63, No. 7, 2004, pp. 1573 - 1576
Published online: 1st June, 2004
DOI: 10.3987/COM-04-10081
Iodoenolcyclization of 2-Allyl Substituted β-Keto Esters under Thermodynamic Conditions

Roberto Antonioletti,* Savina Malancona, and Paolo Bovicelli

*Department of Chemistry, C. N. R. Institute of Biomolecular Chemistry - Roma Section, University “La Sapienza”, Piazzale Aldo Moro 5, I-00185 Roma, Box 34 Roma 62, Italy


An improved procedure for the synthesis of diastereo-enriched tetrasubstituted 4,5-dihydrofurans by using I2-induced enolcyclization of β-keto esters is reported. The reactions using I2 in anhydrous MeCN are considered under thermodynamic control and the more stable trans isomers are preferentially produced.

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Paper | Regular issue | Vol 63, No. 7, 2004, pp. 1577 - 1584
Published online: 27th April, 2004
DOI: 10.3987/COM-04-10083
Synthesis and Electrochemical Properties of π-Extended N-Arylpyrrolo[3,4-d]tetrathiafuluvalenes

Bingzhu Yin,* Yonghua Yang, Zhiqi Cong, and Kimiaki Imafuku*

*Department of Chemistry, Faculty of Science, Kumamoto University, Kurokami 2-39-1, Kumamoto 860-8555, Japan


A series of π-extended N-arylpyrrolo[3,4-d]tetrathiafulvalenes, N-aryl-2-[4,5-bis(ethylthio)-1,3-dithiole-2-ylidene]-(1,3)-dithiolo[4,5-c]pyrroles, (3a-d) were prepared via cross-coupling of 4,5-bis(ethylthio)-1,3-dithiol-2-one (12) with N-aryl-(1,3)-dithiolo[4,5-c]pyrrole-2-thiones (11a-d). The latters were obtained by the reactions of 4,5-bis(bromomethyl)-1,3-dithiole-2-thione (8) with aromatic amines (9a-d). Electrochemical behavior of compounds (3a-d) was studied by means of cyclic voltammetry. It was found that all these compounds (3a-d) have comparable to or lower half-wave potentials than those of N-alkyl-pyrrolo[3,4-d]tetrathiafulvalenes (2a-c).

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Paper | Regular issue | Vol 63, No. 7, 2004, pp. 1585 - 1599
Published online: 14th May, 2004
DOI: 10.3987/COM-04-10087
Synthesis of N-Butyl Side Chain Hydroxylated Metabolites of Roxifiban, a Platelet Glycoprotein IIb/IIIa Receptor Antagonist

Jung-Hui Sun,* George C. Emmett, Janice L. Hytrek, Jia-Sheng Yan, A. Christine Tabaka-Blom, and Christopher A. Teleha

*Department of Chemical Synthesis, Bristol-Myers Squibb Phramaceutical Research Institute, P.O. Box 4000, Princeton, NJ 08543-4000, U.S.A.


Syntheses of three n-butyl side chain hydroxylated metabolites of Roxifiban (5, 6a and 6b) are reported. Initial use of benzyl as hydroxyl protecting group gave poor yield during its removal by catalytic hydrogenation, due to complication from N-O cleavage of the isoxazoline. This problem was eliminated by the use of TBDMS as the hydroxyl protecting group. The chemical structures of these metabolites as well as the intermediates have been fully characterized.

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Paper | Regular issue | Vol 63, No. 7, 2004, pp. 1601 - 1611
Published online: 1st June, 2004
DOI: 10.3987/COM-04-10104
Novel Syntheses of 1-Hydroxy-6- and -5-nitroindole-3-carbaldehydes, and Their Derivatives as Daikon-Phytoalexin Analogs

Koji Yamada, Saori Tomioka, Norihiko Tanizawa, and Masanori Somei*

*Division of Pharmaceutical Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, Ishikawa 920-1192, Japan


1-Hydroxy-6- and -5-nitroindole-3-carbaldehydes are prepared for the first time from 1-methoxy-6- and -5-nitroindole-3-carbaldehydes, respectively, based on the discovery of novel methyl ether cleavage reaction. Utilizing them as common synthetic intermediates, syntheses of several daikon-phytoalexin analogs are achieved.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1613 - 1618
Published online: 23rd April, 2004
DOI: 10.3987/COM-04-10045
Microwave-assisted One-Pot Synthesis of Tri-substituted Imidazoles on Solid Support

Yu Xu, Li-Feng Wan, Hojatollah Salehi, Wei Deng, and Qing-Xiang Guo*

*Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, China


A solvent-free microwave-assisted synthesis of trisubstituted imidazoles is reported. The imidazoles are produced by the condensation of α-hydroxyketone with an aldehyde over silica gel or alumina impregnated with ammonium acetate as the solid support in short time with good yields. An air oxidation mechanism is proposed, and this clean air oxidation considerably reduces the cost of imidazole synthesis.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1619 - 1628
Published online: 14th May, 2004
DOI: 10.3987/COM-04-10059
Fluorinated Heterocyclic Compounds. A Photochemical Approach to a Synthesis of Fluorinated Quinazolin-4-ones

Silvestre Buscemi,* Andrea Pace, Antonio Palumbo Piccionello, Ivana Pibiri, and Nicolò Vivona

*Dipartimento di Chimica Organica “E. Paternò”, Università di Palermo, Viale delle Scienze-Parco d‘Orleans II, 90128 Palermo, Italy


An efficient and generalized photochemical methodology for the preparation of fluorinated quinazolin-4-ones is described. Depending on the starting substrate, quinazolin-4-ones bearing a perfluoroalkyl- or perfluoroaryl- substituent in position 2 or fluorine atoms on any positions of the benzo-fused moiety can easily be obtained. 5-Aryl-3-perfluoroalkylpentafluorophenyl- or 5-polyfluoroaryl-3-phenyl(methyl)-1,2,4-oxadiazoles, respectively, can be considered as ideal precursors that can be transformed into the target quinazolin-4-ones by irradiation in the presence of triethylamine (TEA) (at λ = 313 nm) or pyrene (at λ = 365 nm) in dry methanol or acetonitrile as solvent. Some mechanistic considerations confirm the involvement of a photoinduced electron transfer process.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1629 - 1635
Published online: 21st May, 2004
DOI: 10.3987/COM-04-10069
Synthesis of a New Imidazo[4,5-b]pyridin-5-one via a Vicarious Nucleophilic Substitution of Hydrogen

Maxime D. Crozet, Clément Suspène, Mustapha Kaafarani, Michel P. Crozet, and Patrice Vanelle*

*Laboratory of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, CNRS UMR, University of the Méditerranée (Aix-Marseille 2), 27 Bd Jean Moulin, 13385 Marseille cedex 5, France


A new imidazo[4,5-b]pyridin-5-one was prepared in five steps from 4(5)-nitro-1H-imidazole via a vicarious nucleophilic substitution of hydrogen of 1-benzyl-4-nitro-1H-imidazole with the carbanion generated from chloroform and potassium tert-butoxide. Hydrolysis of 1-benzyl-5-dichloromethyl-4-nitro-1H-imidazole and Knoevenagel condensation between the resulting aldehyde and diethyl malonate catalyzed by titanium(IV) chloride gave the corresponding 4-nitroimidazole bearing at 4 position the diethyl methylenemalonate group.Å@Reduction and cyclization afforded the required ethyl 1-benzyl-5-oxo-4,5-dihydro-1H-imidazo[4,5-b]pyridine-6-carboxylate.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1637 - 1643
Published online: 27th April, 2004
DOI: 10.3987/COM-04-10070
Novel Heterocycles: 4-Methyl-2H-pyrano[6,5-f]cycloalka[2,1-b]2H-chromen-2-ones

Qian Zhang, Ying Chen, Yi Xia, Zhengyu Yang, Peng Xia*

*School of Pharmacy, Fudan University, Yi Xue Yuan Road 138, Shanghai 200032, China


A synthesis of the new heterocycles, 4-methyl-2H-pyrano[6,5- f]cycloalka[2,1-b]2H-chromen-2-ones (3) was described, via the unexpected intermediates 2-chloro-1-chloroethenylidenecycloalkanes (6) from the reaction of 1-ethynylcycloalkanols with thionyl chloride. The mechanism of some steps was discussed.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1645 - 1650
Published online: 14th May, 2004
DOI: 10.3987/COM-04-10079
Thermal Behavior of Dipolarophile-containing 2-Azidocarbonylpyrroles and -indoles

Giorgio Molteni

*Dipartimento di Chimica Organica e Industriale, Centro C.N.R., Università degli Studi di Milano, via Golgi 19, I-20133 Milano, Italy


The thermal reaction of N-allyl- or N-propargyl-2-azidocarbonylpyrroles (2) or -indoles (9) involves competition between intramolecular azide cycloaddition and Curtius rearrangement.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1651 - 1658
Published online: 25th May, 2004
DOI: 10.3987/COM-04-10082
Synthesis and 1,3-Dipolar Cycloaddition Reactions of New Pyrazolo[1,5,4-ef][1,5]bezodiazepines

Latifa Bouissane, Said El Kazzouli, El Mostapha Rakib,* Mostafa Khouili, Abdellah Hannioui, Mohammed Benchidmi, El Mokhtar Essassi, and Gérald Guillaumet

*Department of Chemistry and Environment, Faculty of Science and Technology, BP 523, 23000 Béni-Mellal, Morocco


New pyrazolo[1,5,4-ef][1,5]benzodiazepines have been synthesized by condensation of 7-aminoindazole with β-keto esters, alkylation and 1,3-dipolar cycloaddition. The peri- and regioselective cycloaddition of allylpyrazolo-1,5-benzodiazepinones and 2,4,6-trimethylbenzonitrile oxide was investigated by one- and two- dimensional 1H and 13C NMR spectrum.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1659 - 1665
Published online: 11th May, 2004
DOI: 10.3987/COM-04-10085
Chemical Behavior of 3,5-Dicyanoisoxazoles

Mina Tamura, Tae Nishimura, Nagatoshi Nishiwaki,* and Masahiro Ariga*

*Department of Chemistry, Osaka Kyoiku University, 4-698-1 Asahigaoka, Kashiwara, Osaka 582-8582, Japan


Cyano groups on 3,5-dicyanoisoxazole readily caused nucleophilic addition of alcohols (or amines) to give corresponding imidates (or amidines). Dicyanoisoxazoles was also converted to 3,5-bis(imidazolinyl)isoxazoles upon treatment with 1,2-diamines.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1667 - 1672
Published online: 1st June, 2004
DOI: 10.3987/COM-04-10094
Chemiluminescent Autoxidation of α-Silyl Carbanions Derived from 9-Silyl-10-methylacridanes

Jiro Motoyoshiya,* Kunihiko Tokutake, Motoki Kuroe, Sachiko Yoshioka, Yoshinori Nishii, and Hiromu Aoyama

*Department of Chemistry, Faculty of Textile Science and Technology, Shinshu University, Ueda, Nagano 386-8567, Japan


The autoxidation of α-silyl carbanions derived from 9-trimethysilyl- and 9-triphenylsilyl-10-methylacridanes (1a and 1b) produced the fluorescent N-methylacridone (NMA) accompanied by weak chemiluminescence. Differences in the chemiluminescence quantum yields and the time course of the light emission were detected between the reactions of 1a and 1b, which was due to the substituent on the silicon atom. Additionally, the 9-trimethylsilyl-10-methylacridinium salt also underwent a chemiluminescent reaction when reacted with alkaline hydrogen peroxide. It is probable that these chemiluminescent reactions would proceed via the Peterson-type reaction and involve the dioxasiletanide-like species during the reaction pathway.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1673 - 1677
Published online: 18th May, 2004
DOI: 10.3987/COM-04-10096
Synthesis of Protected (Purin-6-yl)glycines via Pd-Catalyzed α-Arylation of Ethyl N-(Diphenylmethylidene)glycinate with 6-Iodopurines

Michal Hocek*

*Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, CZ-16610 Prague 6, Czech Republic


A synthesis of protected (purin-6-yl)glycines, potential building blocks of stable covalent peptide-nucleic acids conjugates, was achieved via Pd-catalyzed α-arylation of ethyl N-(diphenylmethylidene)glycinate with 6-iodopurine.

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Note | Regular issue | Vol 63, No. 7, 2004, pp. 1679 - 1683
Published online: 1st June, 2004
DOI: 10.3987/COM-04-10102
Reactions of 5-Hydroxymethyl-1H-indole-4,7-dione with Enamines for the First Construction of 1H,5H-Pyrano[3,4-f]indole-4,9-dione Derivatives

Kazuhiro Kobayashi,* Hideo Tanaka, Koujirou Tanaka, Kazutaka Hayashi, Osamu Morikawa, and Hisatoshi Konishi

*Department of Materials Science, Faculty of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan


5-Hydroxymethyl-1-methyl-2,3-diphenyl-1H-indole-4,7-dione (4) was synthesized and the tandem Michael addition/cyclization sequence between this indolequinone and enamines has been used to construct title pyranoindolequinone derivatives (6), (7), and (9).

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Review | Regular issue | Vol 63, No. 7, 2004, pp. 1685 - 1712
Published online: 9th April, 2004
DOI: 10.3987/REV-04-576
Construction of Pyrrolo[3,2-c]quinolines — Recent Advences in the Synthesis of the Martinelline Alkaloids

Miklós Nyerges

*Department of Organic Chemical Technology, Technical University of Budapest, H-1521 Budapest, Gellért tér 4, Hungary


The synthesis of pyrrolo[3,2-c]quinolines is comprehesively reviewed. Synthetic approaches to martinelline alkaloids are then considered which are based upon the endeavors in this area by three independent groups.

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21 data found. 1 - 21 listed