Regular Issue

Vol. 53, No. 6, 2000

19 data found. 1 - 19 listed
Communication | Regular issue | Vol 53, No. 6, 2000, pp. 1239 - 1245
Published online:
DOI: 10.3987/COM-00-8873
Synthesis of Novel Macrocyclic Compounds Utilizing Characteristic Bonding Properties of Hypervalent Sulfur

Noboru Matsumura,* Tsunao Konishi, Hirokazu Hayashi, Masanori Yasui, Fujiko Iwasaki, and Kazuhiko Mizuno

*Department of Applied Chemistry, College of Engineering, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan


The convenient method for the synthesis of 18-, 26-, and 30-membered macrocyclic compounds by utilizing the characteristic bonding properties of the hypervalent sulfur in the 10-S-3 tetraazathiapentalene derivatives and their chemical properties have been described. The structures were established by their spectral data and X-Ray crystallographic analysis.

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Communication | Regular issue | Vol 53, No. 6, 2000, pp. 1247 - 1250
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DOI: 10.3987/COM-00-8880
Photochemistry of 9,10-Dihydro-1,3,5,7-tetramethyl-9-methylenecylooctapyrimidine-2,4-dione: Synthesis of Novel Ring Systems through Electrocyclic Reactions

Kazue Ohkura, Ken-ichi Nishijima, Akiyo Sakushima, and Koh-ichi Seki*

*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan


Photolysis of 1,3,5,7,9-pentamethylcyclooctapyrimidine-2,4-dione (1a) prepared by the photoreaction of 6-chloro-1,3-dimethyluracil with mesitylene in the presence of TFA at low temperature resulted in the formation of the 9-exo-methylene derivative (2), which was further converted into a novel cyclopropa-pentalenopyrimidine (5) and a cyclobutaquinazoline (3) through [4 + 2] and [2 + 2] electrocyclic reactions, respectively. The latter (3) was ultimately transformed into the 9,11-diazapentacyclo[,3.02,5.04,8]dodecane-2,4-dione derivative (4).

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Communication | Regular issue | Vol 53, No. 6, 2000, pp. 1251 - 1254
Published online:
DOI: 10.3987/COM-00-8882
Lewis Acid-mediated Ring Expansion Reaction of Benzo[b ]cyclopropa[e]pyran-7-ol Acetates: Facile Synthesis of 2-Alkyl Substituted 2,3-Dihydro-1-benzoxepins

Yoshiaki Sugita,* Hiroki Hosoya, and Ichiro Yokoe

*Faculty of Pharmaceutical Sciences, Josai University, Sakado, Saitama 350-0295, Japan


In the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf), benzo[b]cyclopropa[e]pyran-7-ol acetates easily reacted with silyl enol ethers to give 2-alkyl substituted 2,3-dihydro-1-benzoxepin derivatives in good yields.

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Communication | Regular issue | Vol 53, No. 6, 2000, pp. 1255 - 1258
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DOI: 10.3987/COM-00-8888
Synthesis of 3a-(Indol-3-yl)-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b ]indole Core of Leptosins D-F Based on Nucleophilic Substitution Reaction on Indole Nucleus

Fumio Yamada, Aya Goto, and Masanori Somei*

*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan


A simple and convenient synthetic methodology for 3a-(indol-3-yl)- 1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole, the core structure of leptosins D–F is developed by applying nucleophilic substitution reaction of 1-hydroxytryptamines.

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Communication | Regular issue | Vol 53, No. 6, 2000, pp. 1259 - 1262
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DOI: 10.3987/COM-00-8892
A Facile Method for Regioselective 6,7-Disubstitution of Pteridine

Shizuaki Murata,* Chihiro Seo, Masato Kujime, and Takashi Sugimoto

*Graduate School of Human Informatics, Nagoya University, Chikusa, Nagoya 464-8601, Japan


Substitution of 1,3-dimethyl-2,4(1H,3H)-pteridinedione 6-triflate by copper acetylide proceeds regioselectively on the 7-position to give corresponding 7-alkynylpteridine 6-triflate whose triflate group can be subsequently replaced by various nucleophiles.

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Communication | Regular issue | Vol 53, No. 6, 2000, pp. 1263 - 1267
Published online:
DOI: 10.3987/COM-00-8899
Synthesis of Alkyl Glycosides Using Trialkyl Borates

Takashi Yamanoi,* Yoshihiro Iwai, and Toshiyuki Inazu*

*The Noguchi Institute, 1-8-1, Kaga, Itabashi-ku, Tokyo 173-0003, Japan


Some trialkyl borates worked as highly reactive glycosyl acceptors of glycosyl acetates. Several allyl glycosides were obtained in good yields by the reaction of glycosyl acetates with triallyl borate using ytterbium(III) trifluoromethanesulfonate as the activator.

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Paper | Regular issue | Vol 53, No. 6, 2000, pp. 1269 - 1283
Published online:
DOI: 10.3987/COM-00-8851
Conformation and Configuration of Humulene Di- and Triepoxides Generated from Four Possible Conformations of Humulene 9,10-Epoxide

Kiyoharu Hayano* and Katsura Mochizuki

*Chemistry Laboratory, Hokkaido College of Education, Ainosato, Sapporo 002-8502, Japan


The complete reaction of humulene 9,10-epoxide (1) with m-CPBA produced a hitherto unknown 2R*, 3R*, 6S*, 7S*, 9S*, 10S*-humulene 2,3;6,7;9,10-triepoxide (6) together with three known triepoxides (7, 8 and 9) in the ratio of 6 : 7 : 8 : 9 = 1.3 : 11.5 : 22.6 : 64.6. The configuration of 6 was determined by X-Ray crystallography. Intermediate products of the epoxidation reaction, two humulene 6,7;9,10- {(2E)-6R*, 7R*, 9S*, 10S* (2) and (2E)-6S*, 7S*, 9S*, 10S* (3)} and two 2,3;9,10-diepoxides {(6E)-2S*, 3S*, 9S*, 10S* (4) and (6E)-2R*, 3R*, 9S*, 10S* (5)} were also produced in the ratio of 2 : 3 : 4 : 5 = 41 : 18 : 35 : 6), and these main conformations (CT, CC, CT and TC) were first determined by X-Ray crystallography (for 3 and 4) and NMR spectroscopy (for 2 and 5). The triepoxide (6) maintained the configuration corresponding to the less stable TT conformation of 1 and the minor TT conformation of 3 and 5.

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Paper | Regular issue | Vol 53, No. 6, 2000, pp. 1285 - 1292
Published online:
DOI: 10.3987/COM-00-8871
Chemoselective Synthesis of 3- and 5-Pyrazolylacetates

Chiara B. Vicentini, Maurizio Manfrini, Manuela Mazzanti, Monica Manferdini, Carlo F. Morelli, and Augusto C. Veronese*

*Dipartimento di Scienze Farmaceutiche-Università di Ferrara, via Fossato di Mortara 17, I-44100, Ferrara, Italy


Methyl 3,5-dioxohexanoate (1) reacts with hydrazines (2) in methanol or acetic acid to give a mixture of the isomeric pyrazolylacetates (3) and (4), whose molar ratio depends on the solvent and hydrazine. 2,2-Dimethyl-5-(1-hydroxy-3-oxobutylidene)-1,3-dioxane-4,6-dione (5) reacts chemoselectively with hydrazines to give the 5-pyrazolylacetates (3) as the only reaction products.

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Paper | Regular issue | Vol 53, No. 6, 2000, pp. 1293 - 1304
Published online:
DOI: 10.3987/COM-00-8874
Synthesis of 3-Hydroperoxy (or Hydroxy)-substituted 1,2-Dioxanes and 1,2-Dioxepanes by the Ozonolysis of Unsaturated Hydroperoxy Acetals

Takahiro Tokuyasu, Toyonari Ito, Araki Masuyama, and Masatomo Nojima*

*Department of Materials Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan


Mono-ozonolysis of dienes in methanol gave in each case the corresponding unsaturated hydroperoxy acetals. The reaction of the hydroperoxides with ozone in the solvent system such as AcOH-CH2Cl2 resulted in the production of the corresponding hydroperoxy (or hydroxy)-substituted 1,2-dioxanes or 1,2-dioxepanes in good yield. By the treatment of the derived products with TMSOTf-Et3SiH, replacement of the methoxy (or hydroxy) group by hydrogen was accomplished.

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Paper | Regular issue | Vol 53, No. 6, 2000, pp. 1305 - 1316
Published online:
DOI: 10.3987/COM-00-8877
Synthesis of Benzacridine and Pyridoacridine via Diels-Alder Reaction of Acridonequinone

Yoshie Horiguchi,* Shinichi Sakuma, Hideki Suzuki, and Takehiro Sano

*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan


Synthesis of benz[b]acridones (8) and pyrido[3,2-b]acridones (15) was achieved by Diels-Alder reaction of acridonequinones (5) with several activated 1,3-dienes. The addition proceeded in a regioselective manner under mild conditions, thus providing a convenient method for the construction of polycyclic nitrogen heterocycles.

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Paper | Regular issue | Vol 53, No. 6, 2000, pp. 1317 - 1328
Published online:
DOI: 10.3987/COM-00-8884
Solution Parallel Synthesis of Cyclic Guanidines

Christelle Marmillon, Jacques Bompart, Michèle Calas, Roger Escale,* and Pierre-Antoine Bonnet

*E. A. 2414 Pharmacochimie et Biomolécules, UFR Sciences Pharmaceutiques et Biologiques, 15, av. C. Flahault, 34060 Montpellier cedex 2, France


An efficient method for the solution phase synthesis of cyclic guanidines is presented. A variety of 2-substituted monoprotected propanediamines react with a set of 5-substituted 2-methylthio-3,4,5,6-tetrahydropyrimidines under Rathke conditions for the construction of a potential library of 81 cyclic guanidines.

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Paper | Regular issue | Vol 53, No. 6, 2000, pp. 1329 - 1336
Published online:
DOI: 10.3987/COM-00-8891
[2+2] Photocycloaddition Reaction of 5-Phenyl-1H -furan-2,3-dione to Phenylethylene

Yoshie Horiguchi, Toshiaki Saitoh, Nobuyuki Koseki, Hideki Suzuki, Jun Toda, and Takehiro Sano*

*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan


The photocycloaddition reaction of 5-phenylfuran-2,3-dione (1) to phenylethylene proceeded in a [2+2] manner with regio- and stereoselectivities to give 2-oxabicyclo[3.2.0]heptane-3,4-diones with 7-endo-phenyl as a major adduct (3) and 7-exo-phenyl stereochemistries as a minor one (4). The reaction demonstrated that dioxofuran is a useful synthon for synthesis of substituted cyclobutane derivatives.

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Note | Regular issue | Vol 53, No. 6, 2000, pp. 1337 - 1342
Published online:
DOI: 10.3987/COM-99-8843
Electrochemical Synthesis of 5-Amino-4-benzoyl-3-phenylfuran-2-carbonitrile

Belén Batanero, Mariano Vago, and Fructuoso Barba*

*Department of Organic Chemistry, University of Alcalá, 28871 Alcalá de Henares (Madrid), Spain


Cathodic reduction of 2-bromo-2-cyanoacetophenone afforded 5-amino-4-benzoyl-3-phenylfuran-2-carbonitrile in an one pot reaction. The process is discussed and all the secondary products are isolated and characterized.

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Note | Regular issue | Vol 53, No. 6, 2000, pp. 1343 - 1350
Published online:
DOI: 10.3987/COM-00-8856
Three New Diterpene Alkaloids from Spiraea japonica

Bin-Gui Wang, Ling Li, Xiao-Sheng Yang, Zhi-He Chen, and Xiao-Jiang Hao*

*Laboratory of Phytochemistry, Kunming Institute of Botany, The Chinese Academy of Sciences, Kunming 650204, China


Chemical investigation of the basic fraction from the roots of Spiraea japonica var. acuta has resulted in the isolation of three new diterpene alkaloids, spiramines X (1), Y (2) and Z (3), along with five known compounds, spiradine F (4), and spiramines A, B, P (5), and U (6). The structures of 1-3 were determined by spectral and chemical methods. Antiplatelet aggregation activities of compounds (1- 6) were tested.

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Note | Regular issue | Vol 53, No. 6, 2000, pp. 1351 - 1359
Published online:
DOI: 10.3987/COM-00-8859
Condensation Reactions of a Nitrodienamine with Organocopper and Alkyllithium Reagents Prepared from Pyrrole Derivatives

Takeshi Koike,* Yoshifumi Shinohara, Takeshi Nishimura, Masanori Hagiwara, Seisho Tobinaga, and Naoki Takeuchi

*Showa Pharmaceutical University, Higashi-tamagawagakuen 3-3165, Machida, Tokyo 194-8543, Japan


Condensation reactions of a nitrodienamine (1) with Grignard, organocopper and alkyllithium reagents prepared from pyrrole derivatives were investigated.

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Note | Regular issue | Vol 53, No. 6, 2000, pp. 1361 - 1370
Published online:
DOI: 10.3987/COM-00-8865
Stereoselective Synthesis of the 3-Hydroxytetrahydropyran Part of Mucocin, an Antitumor Agent, Based on Rearrangement-Ring Expansion Reaction of a Tetrahydrofuran Derivative

Shunya Takahashi, Kenji Fujisawa, Nobuo Sakairi, and Tadashi Nakata*

*RIKEN (The Institute of Physical and Chemical Research), Wako, Saitama 351-0198, Japan


The synthesis of the 2,6-disubstituted 2,3-trans-3-hydroxy-tetrahydropyran part of mucocin, a potent antitumor agent, was accomplished based on the zinc acetate-induced ring expansion reaction of a tetrahydrofuran having a choloromethanesulfonate on the C2-side chain.

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Note | Regular issue | Vol 53, No. 6, 2000, pp. 1371 - 1378
Published online:
DOI: 10.3987/COM-00-8883
Synthesis of Enantiopure 8-Aminomethylindolizines from Glutamine by Stereoelectronically Controlled Cationic Cyclization

Thomas Lehmann and Peter Gmeiner*

*Department of Medicinal Chemistry, Emil Fischer Center, Friedrich-Alexander University, Schuhstraße 19, D-91052 Erlangen, Germany


Starting from natural glutamine the synthesis of the 8-aminomethylindolizine (4b) was accomplished. The construction of the ring system was performed by employing a cationic 6-exo π-cyclization of an intermediate aziridinium salt. Transformation of the N,N-dibenzyl protected amine (4b) into the pharmacologically relevant target compound (11) is also describcd.

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Review | Regular issue | Vol 53, No. 6, 2000, pp. 1379 - 1419
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DOI: 10.3987/REV-00-529
4- and 5-Oxocarboxylic Acids as Versatile Synthons for the Preparation of Heterocycles

Ferenc Csende and Géza Stájer*

*Institute of Pharmaceutical Chemistry, University of Szeged, PO Box 121, H-6701 Szeged, Hungary


Conversions of 4- and 5-oxocarboxylic acids for the preparation of heterocycles are discussed. The review illustrates the importance and variability and presents the synthetic applicability of these versatile synthons.

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Review | Regular issue | Vol 53, No. 6, 2000, pp. 1421 - 1448
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DOI: 10.3987/REV-00-530
Alkylation and Related Electrophilic Reactions at Endocyclic Nitrogen Atoms in the Chemistry of Tetrazoles

Vladimir A. Ostrovskii and Andrei O. Koren*

*Brain Imaging Center, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD 21224, U.S.A.


This review summarizes the results of studies of reactions between tetrazoles and various electrophilic agents, published over the past twenty years. Where possible, mechanisms of the reactions are discussed in detail and consideration is given to how the rate and selectivity of processes are influenced by the nature of reactants, parameters of reaction medium, and by other factors.

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19 data found. 1 - 19 listed