Regular Issue

Vol. 55, No. 9, 2001

18 data found. 1 - 18 listed
Communication | Regular issue | Vol 55, No. 9, 2001, pp. 1635 - 1639
Published online:
DOI: 10.3987/COM-01-9262
Synthesis and Complexing Properties of Thiacrownophanes

Seiichi Inokuma, Takashi Funaki, Masayuki Tanakajima, Shinji Nabekura, Keigo Isawa, and Jun Nishimura*

*Gunma University, Department of Chemistry, 1-5-1 Tenjin-cho, Kiryu 376-8515, Japan


Novel thiacrownophanes (1) (cis-form) and (2) (trans-form) were prepared by means of intramolecular [2 + 2] photocycloaddition of styrene derivatives. The ratio of 1:2 was significantly dependent on the oxyethylene chain length of the linkage between the two aromatic nuclei of precursors. In a liquid-liquid extraction, thiacrownophanes (1c) possessing three ethereal oxygens showed perfect selectivity with high efficiency toward Ag+ ion. From ESI-MS analysis, 1c was found to form a 1:1 complex with Ag+ ion in MeCN-H2O homogeneous system.

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Communication | Regular issue | Vol 55, No. 9, 2001, pp. 1641 - 1651
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DOI: 10.3987/COM-01-9264
Synthesis of N-Functionalized Carbodiimides, Hydantoins, 1,3-Diazetidines, and Imidazolidine Derivatives from N-Vinylic Phosphazenes Derived from β-Amino Acids

Francisco Palacios,* Marta Legido, Itziar Pérez de Heredia, José María Ezpeleta, and Gloria Rubiales

* Departamento de Química Orgánica, Facultad de Farmacia, Universidad del País Vasco, Apartado 450, 01080 Vitoria-Gasteiz, Spain


Synthesis of N-vinylic carbodiimides through Aza-Wittig reaction of N-vinylic phosphazenes with isocyanates is reported. These heterocumulenes are used for the preparation of unsymmetrical ureas and nitrogen heterocycles such as hydantoins, 1,3-diazetidines, imidazolidinones, and bis-imidazolidinone azines.

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Communication | Regular issue | Vol 55, No. 9, 2001, pp. 1653 - 1657
Published online:
DOI: 10.3987/COM-01-9284
New Noroleanane-Type Triterpene Saponins with Gastroprotective Effect and Platelet Aggregation Activity from the Flowers of Camellia japonica: Revised Structures of Camellenodiol and Camelledionol

Masayuki Yoshikawa,* Toshio Morikawa, Emi Fujiwara, Teruki Ohgushi, Yasunobu Asao, and Hisashi Matsuda

*Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8412, Japan


The methanolic extract from the flowers of Camellia japonica was found to exhibit potent gastroprotective effect on ethanol-induced gastric mucosal lesions in rats and platelet aggregation activity. Through bioassay-guided separation, three new 28-noroleanane-type triterpene saponins, camelliosides A, B, and C, and an oleanane-type triterpene saponin, camellioside D, were isolated from the methanolic extract. The absolute stereostructures of camelliosides A—D were determined on the basis of physicochemical and chemical evidence, which included the structure revision of the triterpene part, camellenodiol and camelledionol, using X-Ray crystallographic analysis and modified Mosher's method. Camelliosides A and B showed gastroprotective and platelet aggregating effects.

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Communication | Regular issue | Vol 55, No. 9, 2001, pp. 1659 - 1662
Published online:
DOI: 10.3987/COM-01-9288
Synthesis and Some Properties of Phosphoimino-1-azaazulene Derivatives

Noritaka Abe,* Hiroyuki Fujii, Kenji Tahara, and Motoo Shiro

*Department of Chemistry, Faculty of Science, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8512, Japan


3-Phenyl-8-triphenylphosphoimino- and 2-triphenylphospho-imino-1-azaazulenes were prepared by the reaction of the corresponding 8- and 2-amino-1-azaazulenes with triphenylphosphine dibromide. The structure of 3-phenyl-8-triphenylphosphoimino-1-azaazulene was investigated by X-Ray crystallographic analysis and molecular orbital calculation. The P-atom has trigonal bipiramidal coordination and the intramolecular distance between the N-1 and the P-atom is 2.762(6) Å; the existence of an interaction between N-1 and the P-atom is considered.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1663 - 1678
Published online:
DOI: 10.3987/COM-01-9212
Synthesis of 3-Substituted Isoindolin-1-ones by Regioselective Cyclization of Nitrile with a Styryl Double Bond

Fen-Tair Luo* and Chin-Hsin Chen

*Institutue of Chemistry, Academia Sinica,, Nankang, Taipei,11529,Taiwan, R.O.C.


An efficient preparation of 3-substituted isoindolin-1-one was established via basic condensation of aromatic or aliphatic aldehyde with 6-alkoxy-3-methylbenzene-1,2,4-tricarbonitrile (1) in a one-pot reaction. The key step involved regioselective either hydrolysis or nucleophilic attack of the hydroxide anion to the 2-cyano group followed by 5-exo-trig cyclization with the involvement of the styryl double bond. The structure of isoindolinone and regiochemistry of the cyclization products were proved by spectroscopic methods.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1679 - 1687
Published online:
DOI: 10.3987/COM-01-9251
Synthesis of 5-Substituted Pyrido[2,3-d]pyrimidines as Analogues of the Antifolates Methotrexate, DDATHF and Pemetrexed (LY231514)

Franz Schönfeld and Reinhard Troschütz*

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


The preparation of 5-substituted pyrido[2,3-d]pyrimidines (18,19,21) as analogues of the antifolates methotrexate (1), DDATHF (2) and pemetrexed (LY231514) (3) is outlined, starting from methyl 4-(3-oxobutyl)benzoate (4). Key steps involve high yielding Knoevenagel condensation of 4 with malononitrile (5), treatment with dimethylformamide dimethyl acetal (DMF-DMA) (7), cyclisation with hydrochloric acid and pyrimidine annulation with guanidine (11). The resulting pyrido[2,3-d]pyrimidines (13, 14) are coupled with diethyl L-glutamate (11) and transformed to 18, 19 and 21.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1689 - 1701
Published online:
DOI: 10.3987/COM-01-9255
Diastereoselective Reduction of Chiral Enaminolactones: A Short and Convenient Route to Enantio-pure (+)-Tashiromine

Olivier David, Christian Bellec, Marie-Claude Fargeau-Bellassoued, and Gérard Lhommet*

*Laboratoire de Chimie des Hétérocycles UMR 7611, Université P. et M. Curie, case courrier 43, 4 Place Jussieu, F-75252 Paris Cedex 05, France


Some chiral β-enamino lactones were reduced catalytically or chemically with good to moderate diastereoselectivity owing to a chiral induction originated from (S)-α-methylbenzylamine. The scope of the present methodology has been extended to the synthesis of an indolizidine alkaloid : (+)-tashiromine. A synthesis of this natural product was achieved in a short and attractive manner (five steps from thiolactam) to enantiopure alkaloid in 25 % overall yield.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1703 - 1710
Published online:
DOI: 10.3987/COM-01-9256
α-Benzotriazolylpyridines and Their N-Oxides

Alan R. Katritzky,* Thomas Kurz, Suoming Zhang, Michael Voronkov, and Peter J. Steel*

*Center for Heterocyclic Compounds , Department of Chemistry, University of Florida, P. O. Box 117200, Gainesville, FL 32611-7200, U.S.A.


α-Benzotriazolyl-substituted pyridines, -quinolines and -isoquinolines have been prepared by reactions of pyridine, quinoline and isoquinoline N-oxides with 1-tosylbenzotriazole in the presence of triethylamine. Treatment of a-benzotriazolylpyridines, -quinolines and -isoquinolines with hydrogen peroxide in glacial acetic acid afforded N-oxides, the structures of which were determined by X-Ray crystallography. Reactions of 1-(2-pyridinyl)-benzotriazole with alkyl halides or tosylates led to the corresponding N-alkylpyridinium salts.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1711 - 1725
Published online:
DOI: 10.3987/COM-01-9277
Regioselectivity in Formal [3+2] Cycloaddition Reaction of 5-Alkoxyoxazoles with Diethyl Oxomalonate and 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone

Hiroyuki Suga,* Xiaolan Shi, Toshikazu Ibata, and Akikazu Kakehi

*Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan


Tin(IV) chloride-catalyzed formal [3 + 2] cycloaddition of 5-alkoxy-2-(p-methoxyphenyl)- or 2-phenyloxazoles with diethyl oxomalonate gave 4,5,5-tris(alkoxycarbonyl)-2-oxazolines in high regioselectivity. Under similar conditions, 4-substituted 5-alkoxy-2-methyloxazoles showed a trend to shift the regioselectivity in favor for 3-oxazolines rather than 2-oxazolines. Reaction of 5-alkoxy-4-ethoxycarbonyloxazoles with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone proceeded only under high pressure to give 2-oxazolines exclusively.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1727 - 1735
Published online:
DOI: 10.3987/COM-01-9278
12H-[2]-Benzothiepino[6,5a,5-bc]benzofuran: Synthesis of a Sulfur-Analog of Galanthamine

Matthias Treu, Ulrich Jordis,* and Kurt Mereiter

*Institute of Organic Chemistry, Vienna University of Technology, Getreidemarkt 9/154, A-1060 Vienna, Austria


An analog of the anti-Alzheimer drug galanthamine, carrying a SO2-moiety instead of an amino-functionality, has been synthesized as a racemic mixture using tandem cyclization techniques to form a new four membered heterocyclic ring system.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1737 - 1746
Published online:
DOI: 10.3987/COM-01-9279
A Novel Synthesis of 3-Nitropyridine Derivatives from N-Silyl-1-azaallylAnions

Takeo Konakahara,* Ryo Ogawa, Sanae Tamura, Akikazu Kakehi, and Norio Sakai

*Department of Industrial Chemistry, Faculty of Science and Technology, Science University of Tokyo, 2641 Yamazaki, Noda, Chiba 278-8510, Japan


Seven kinds of 3-nitropyridines were synthesized from N-silyl-1-aza-allyl anions and ethyl 3-etoxy-2-nitropropenoate in good yields, and regio-selectivity of the cyclization was also discussed.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1747 - 1757
Published online:
DOI: 10.3987/COM-01-9283
One Pot Synthesis of Fused Pyrimidines from 2-[N-(Methylthiothiocarbonyl)amino]acetate

A. Z. M. Shaifullah Chowdhury,* Yasuyuki Shibata, Masatoshi Morita, Kunimitsu Kaya, and Tomoharu Sano

*National Institute for Environmental Studies, Environmental Chemistry Division, 16-2 Onogawa, Tsukuba, Ibaraki 305-0053, Japan


A variety of 3-substituted fused pyrimidines (4a-k) are readily obtained from the 2-amino esters (2a-k) with 2-[N-(methylthiothiocarbonyl)-amino]acetate (1). Condensed imidazo[1,2-c]pyrimidine ring system was also constructed in a one-pot process by reacting heteroaromatic 2-amino nitriles (3a-l) with 1, obtaining a number of novel tri- and tetracyclic compounds (5a-l).

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1759 - 1769
Published online:
DOI: 10.3987/COM-01-9287
Cyclization Reactions of 2-Methylbenzenesulfonamides Using N,N-Dimethylcarbamoyl Chloride, N,N-Dimethylthiocarbamoyl Chloride, and N,N-Dimethylsulfamoyl Chloride

Masahiko Takahashi,* Tomoya Morimoto, Ken-ichi Isogai, Sousi Tsuchiya, and Keisuke Mizumoto

*Department of Materials Sciences, Faculty of Engineering, Ibaraki University, 4-12-1 Nakanarusawamachi, Hitachi, Ibaraki 316-8511, Japan


Generation of C,N-dianions (2) of 2-methylbenzenesulfonamides (1) followed by addition of N,N-dimethylcarbamoyl chloride gave 2-(N,N-dimethylcarbamoyl)-methylbenzenesulfonamides (3), which were cyclized to 3,4-dihydro-2H-1,2-benzo[e]thiazin-3-one 1,1-dioxides (5). 3-Dimethylamino-2H-1,2-benzo[e]thiazine 1,1-dioxides (7) were obtained in one step by the reaction of 2 with N,N-dimethylthiocarbamoyl chloride. On the other hand, the reaction of 2 with N,N-dimethylsulfamoyl chloride yielded 2,2’-ethylene-bis(benzenesulfonamide)s (10) and / or 2,3-dihydro-1,2-benzothiazole 1,1-dioxides (11).

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1771 - 1777
Published online:
DOI: 10.3987/COM-01-9295
Reaction of Quinoline 1-Oxides with Sodium Methoxide in the Presence of Lead(IV) Acetate

Yoshinobu Tagawa,* Keitaro Tanaka, Katsuya Yamashita, Yoshinobu Goto, and Masatomo Hamana

*Faculty of Pharmaceutical Sciences, Fukuoka University, Nakamura, Jonan-ku, Fukuoka, 814-0180, Japan


In the presence of lead(IV) acetate, the reaction of quinoline 1-oxide with methoxide anion under various reaction conditions gives 2-methoxyquinoline 1-oxide without deoxygenation of N-oxide group. Reaction of 4-substituted quinoline 1-oxides with methoxide anion also resulted in the corresponding 4-substituted 2-methoxyquinoline 1-oxides under the same reaction conditions. As the reaction mechanism, ionic pathway is suggested rather than radical pathway through the investigation using radical initiators.

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Paper | Regular issue | Vol 55, No. 9, 2001, pp. 1779 - 1788
Published online:
DOI: 10.3987/COM-01-9296
Reaction of Methyl 2-Arylethylcarbamates with Thionyl Chloride: Formation of Benzothiazine and Benzo[b]thiophene Ring Systems

Kunihiko Mohri,* Yuki Yoshida, Takako Awano, Yoshiaki Takeuchi, and Kimiaki Isobe

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


The reaction of methyl 2-arylethylcarbamates with thionyl chloride induced a sulfur mediated ring closure to form benzothiazine and benzo[b]thiophene ring systems with concomitant chlorination of the aromatic ring.

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Note | Regular issue | Vol 55, No. 9, 2001, pp. 1789 - 1803
Published online:
DOI: 10.3987/COM-01-9218
Synthesis and Vasorelaxant Potency of Monagra. A Chiral 5-(2-Methyl-2,3-dihydro-7-benzofuryl)pyrazolopyrimidone Analog of Viagra®

Nader R. Al-bojuk, Mustafa M. El-Abadelah,* Salim S. Sabri, Alain Michel, Wolfgang Voelter, Cäcilia M.-Mössmer, and Yousef Al-Abed

*Chemistry Department , Faculty of Science, University of Jordan, Amman 11942, Jordan


Synthesis and properties of a chiral 5-(2-methyl-2,3-dihydro-7-benzofuryl)pyrazolo[4,3-d]pyrimidin-7-one (3), an analog of Viagra“ (1) and Biagra (2), are described. The key material, (±)-3-methyl-2,3-dihydrobenzofuran-7-carboxylic acid (8a) was resolved into the (S)-8b (95% ee) and (R)-8c (99% ee) enantiomers using, respectively, (-)-cinchonidine and (+)-cinchonine. The absolute configuration of 8c was determined as R by X-Ray measurements. Preliminary in vitro experiments on rat isolated thoracic aorta show that the vasorelaxant potency of 3b,c is truly higher than that of 1 and 2.

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Note | Regular issue | Vol 55, No. 9, 2001, pp. 1805 - 1812
Published online:
DOI: 10.3987/COM-01-9265
Microwave and BF3 Promoted Rearrangement of Allyloxycoumarins to Allylcoumarins and Dihydrofurocoumarins

Mohammad R. Saidi* and Fatemeh Rajabi

*Department of Chemistry, Sharif University of Technology, P.O. Box 11356-9516, Tehran, Iran


Allyl, crotyl, methallyl and cinamyl ethers of 4-hydroxy-, 7-hydroxy-, and 4-methyl-7-hydroxycoumarins have been efficiently synthesized and rearranged to substituted allylcoumarins under microwave irradiation. Irradiation of allylcoumarins in the presence of BF3/ether directly produced substituted dihydrofurocoumarins in good yields.

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Note | Regular issue | Vol 55, No. 9, 2001, pp. 1813 - 1816
Published online:
DOI: 10.3987/COM-01-9282
A Convenient Route to the Soluble Guanylate Cyclase Activator YC-1 and Its N2 Regioisomer

Patricia A. Fernandez, Tom Bellamy, Marcel Kling, David J. Madge, and David L. Selwood*

*Biological Chemistry, The Wolfson Institute for Biomedical Research, University College London, The Cruciform Building, Gower Street, London WC1E 6BT, U.K.


A new route to the soluble guanylate cyclase (sGC) activator YC-1 and its N2 regioisomer has been established with a Mitsunobu mediated N-alkylation as the key step. The route is utilised in the synthesis of a potential photoaffinity label.

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18 data found. 1 - 18 listed