Regular Issue

Vol. 53, No. 12, 2000

24 data found. 1 - 24 listed
Communication | Regular issue | Vol 53, No. 12, 2000, pp.2601-2606
Published online:
DOI: 10.3987/COM-00-8933
Cycloaddition Reaction of Naphtho[b]cyclopropene with Tropone Derivatives under the Presence of Ytterbium Complex to Form Cyclic Ethers or Cyclic Ketones: Solvent Effect of Chloroform and Benzene on the Reaction Path

Katsuhiro Saito,* Shinichi Ando, and Yoji Kondo

*Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan

Abstract

Reactions of naphtho[b]cyclopropene with 2-substituted tropone derivatives in chloroform under the presence of ytterbium complex afforded two types of cyclic ether compounds via a [8π+2σ] type cycloaddition reactions. On the other hand, the similar reactions but using benzene as a solvent proceeded through a [6π+2π] type cycloaddition path to form cyclic ketone compounds.

PDF (75KB)
Communication | Regular issue | Vol 53, No. 12, 2000, pp.2607-2610
Published online:
DOI: 10.3987/COM-00-9020
Novel Synthesis of Tetrahydro-2(1H)-quinolones Using Diels-Alder Reactions of 1-Arylsulfonyl-2(1H)-pyridones Acting as Dienophiles

Reiko Fujita,* Kazuhiro Watanabe, Wakako Ikeura, Yosuke Ohtake, and Hiroshi Hongo*

*Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan

Abstract

1-Arylsulfonyl-2(1H)-pyridones having an electron-withdrawing group at the 5-position were prepared, and the first example is presented relating to a novel synthetic methodology of tetrahydro-2(1H)-quinolones by Diels-Alder reactions of those with 2,3-dimethyl-1,3-butadiene.

PDF (47KB)
Communication | Regular issue | Vol 53, No. 12, 2000, pp.2611-2615
Published online:
DOI: 10.3987/COM-00-9056
Radical Cyclization of Oxime Ethers Derived from Monosaccharides Aiming at the Synthesis of Dysiherbaine and Related Stereoisomers

Takeaki Naito,* J. Somarajan Nair, Akiyoshi Nishiki, Kazuhiko Yamashita, and Toshiko Kiguchi

*Kobe Pharmaceutical University, Motoyamakita, Higashinada, Kobe 658-8558, Japan

Abstract

Stannyl radical-mediated cyclization of oxime ethers (6), (14), (22), and (29) derived from glucose and galactose afforded the cyclized aminosugar derivatives (7), (8), (15, 16 and 17), (23), (24), and (30, 31 and 32) which would serve as key intermediates for the synthesis of dysiherbaine and its isomers.

PDF (43KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2617-2627
Published online:
DOI: 10.3987/COM-00-8869
Reactivity of 7-Aminoindazole as a Bidendate Nucleophile

El Mostapha Rakib, Mohammed Benchidmi, El Mokhtar Essassi, Abdelaziz El Bouadili, Mostafa Khouili, Mark Visseaux, and M. Dolors Pujol*

*Laboratori de Química Farmacèutica, Departament de Farmacologia i Qúimica Terapèutica, Facultat de Farmàcia, Universitat de Barcelona, Av. Diagonal 643, 08028 Barcelona, Spain

Abstract

A simple route for the preparation of two new classes of heterocyclic systems: halopyrazolo[4,5-h]quinolines and halopyrazolo[1,5,4-ef][1,5]benzodiazepines, is presented. The effect of the solvent and the reactivity of pyrazolo-1,5-benzodiazepine were studied.

PDF (92KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2629-2642
Published online:
DOI: 10.3987/COM-00-8929
Chemical Oxidation of Taxoids with m-CPBA and Dimethyl Dioxirane: Regioselective Epoxidation of Taxinine J Derivatives

Tohru Horiguchi, Masanori Nagura, Qian Cheng, Takayuki Oritani,* and Toshio Kudo

*Laboratory of Applied Bioorganic Chemistry, Division of Life Science, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan

Abstract

Epoxidation of taxinine J derivative (2c) with m-CPBA afforded a mixture of 4 Éø,20-epoxide (3), 4Éø,20 : 11β,12β-diepoxide (4) and 11 β,12β-epoxide (5). The proportion of the yields was dependent on temperature (3 : 4 = 80 : 10 at room temperature, 4 : 5 = 68 : 25 at 0-10°C). The reactions of derivatives of taxinine (2b) with m-CPBA and dimethyldioxirane (DMDO) were also investigated.

PDF (462KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2643-2652
Published online:
DOI: 10.3987/COM-00-9006
Synthesis and Properties of α-Thiagra. A Substituted 5-(2-Thienyl)pyrazolo[4,3-d]pyrimidin-7-one Bioisostere of Viagra®

Mustafa M. El-Abadelah,* Salim S. Sabri, Monther A. Khanfar, Wolfgang Voelter, Raid J. Abdel-Jalil, Cäcilia Maichle-Mössmer, and Yousef Al-Abed

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

Abstract

For structure-activity manipulations, the compound α-thiagra (3) a thiophene bioisostere of viagra®, has been prepared and its X-Ray structure determined. The crystallographic data show that the thiophene and pyrazolo[4,3-d]pyrimidone hetero-ring systems are nearly coplanar by virtue of an adequate intramolecular hydrogen-bond between the pyrimidone NH and the oxygen lone pair of the 3’-ethoxy group.

PDF (116KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2653-2660
Published online:
DOI: 10.3987/COM-00-9009
Studies on Ring Opening Reactions of N-Phenylsulfonyl Substituted Spiro-β-lactamsa

Piero Dalla Croce and Concetta La Rosa*

*Istituto di Chimica Organica, Facoltà di Farmacia, Università degli Studi di Milano, Via Venezian 21, I-20133 Milano, Italy

Abstract

Ring opening reactions of the spiro-β-lactam 5-benzoyl-3-phenyl-2-phenylsulfonyl-7-thia-2,5-diazaspiro[3.4]octan-1-one (1a) under hydrolytic, reductive and alkylating reaction conditions are reported. There is evidence for the influence of the spiro structure on azetidinone ring reactivity, which is also affected by the presence of the N-phenylsulfonyl group.

PDF (119KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2661-2666
Published online:
DOI: 10.3987/COM-00-9017
Synthesis and Crystal Structure of Pyrazoline Derivative of Pulegone

Suleimenov Yerlan Melsovich, Abdul Majeed Khan, Atazhanova Gayane Abdulkakhimovna, Muhammad Iqbal Choudhary, Khasenov Bekbolat Baurzhanovich, Kulyjasov Arman Tabylovich, Turdybekov Koblandy Muboryakovich, Dembitsky Alexandr Dmitrievich, Adekenov Sergazy Mynzhasarovich, and Atta-ur-Rahman

*H. E. J. Research Institute of Chemistry, International Centre for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan

Abstract

An interesting pyrazoline derivative, 3,3-dimethyl-3H-pyrazo[4,5-2’(S)-methyl]cyclohexane-1,2-dioxide (3), has been obtained by the transformation of monoterpene ketone, pulegone (1) using hydroxylamine hydrochloride and sodium nitrite through a stable intermediate (2).

PDF (85KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2667-2677
Published online:
DOI: 10.3987/COM-00-9023
[4+2] Cycloaddition Reactions between 2,4-Diamino-1-thia-3-azabutadienes and Ketene. Synthesis of New 1,3-Thiazin-6-ones, 1,3-Thiazine-6-thiones and 2-Thioxopyrimidin-4-ones

Cyrille Landreau, David Deniaud, Françoise Reliquet, Alain Reliquet, and Jean Claude Meslin*

*Laboratoire de Synthèse Organique, UMR, C.N.R.S. 6513, Faculté des Sciences et des Techniques, Université de Nantes, 2, rue de la Houssiniere, 44072 Nantes Cedex, France

Abstract

The reaction of 2,4-diamino-1-thia-3-azabutadienes with an excess of ketene afforded 2-amino-1,3-thiazin-6-ones and 2-thioxopyrimidin-4-ones by [4+2] cycloaddition reaction. Reaction between thiazabutadienes and ketene gave rise to aminothiazinones, which were sulfured by action of phosphorus pentasulfide leading to aminothiazinethiones. Furthermore, synthesis of thioxopyrimidinones starting from S-methyl salts of thiazadienes is described.

PDF (410KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2679-2688
Published online:
DOI: 10.3987/COM-00-9027
Carbazolyl Nitrenium Cations: Generation and Reactions

Dariusz Bogdal*

*Department of Chemistry, Politechnika Krakowska, ul. Warszawska 24, 31-155 Krakow, Poland

Abstract

Carbazolyl nitrenium cations were generated during the thermolysis and photolysis of 1-carbazol-9-yl-2,4,6-triphenylpyridinium (Py+-Cz) tetrafluoroborate in 2,2,2-trifluoroethanol- and TFA - mesitylene mixtures. The thermolysis of Py+-Cz in TFA-mesitylene mixture gave 9-mesitylcarbazole in good yield along with carbazole, non-symmetrical mesitylene dimer, 2,4,6-triphenylpyridine, and a small amount of 9-(3,5-dimethylbenzyl)carbazole, whereas the thermolysis in trifluoroethanol - mesitylene mixture gave 9-mesitylcarbazole as the main product along with carbazole and 2,4,6-triphenylpyridine. The product distributions lead to two major conclusions. First, photolysis and thermolysis of Py+-Cz salt produce nitrenium ions that can be in singlet or triplet state dependant on the reaction conditions. Second, the carbazolyl nitrenium ion exhibits singlet state in the ground state.

PDF (54KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2689-2700
Published online:
DOI: 10.3987/COM-00-9033
Mass Spectral Analysis of Cardiac Steroids Isolated from Elaeodendron glaucum

Hiroko F. Kasai,* Ken-ichi Kawai, and Kazutake Shimada

*Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan

Abstract

The electron ionization mass spectrometric data of three cardiac glycosides having an unusual sugar linkage, elaeodendrosides A, B and C, are reported. The decomposition patterns upon EI-MS were investigated by means of collision induced dissociation utilizing B/E linked scan experiments and deuterium labeling techniques. Besides the fragment ions related to aglycones, elaeodendroside A which is a 12-keto steroid, produces decomposition ions derived from cleavage of steroidal C- and D-rings. Elaeodendrosides B and C, which have a six-membered hemiacetal ring, generate ions derived from the cleavage of sugar rings and the aforementioned unusual sugar linkage.

PDF (117KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2701-2708
Published online:
DOI: 10.3987/COM-00-9035
Reactions of a Nitrodienamine with 1-Protected Indolyllithium

Takeshi Koike,* Yoshifumi Shinohara, Seisho Tobinaga, and Naoki Takeuchi

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

Abstract

Reactions of a nitrodienamine (1) with indolyllithiums prepared from 1-protected indole derivatives were investigated.

PDF (127KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2709-2718
Published online:
DOI: 10.3987/COM-00-9037
5,6-Dinitrophenyl and 5-Aminophenyl-6-nitrophenyl Analogues of the ACAT Inhibitor 5,6-Diphenyl-3-alkylaminopyridazines

Lucio Toma,* Donatella Nava, Giuseppe Celentano, Maria Paola Giovannoni, Vittorio Dal Piaz, Byoung-Mog Kwon, Mi-Kyiung Kim, Young-Kook Kim, and Daniela Barlocco*

*Istituto di Chimica Farmaceutica e Tossicologica, Università di Milano, Viale Abruzzi 42, 20131 Milano, Italy

Abstract

A series of dinitro and monoamino-mononitro analogues of the 5,6-diphenyl-3-alkylaminopyridazines were synthesized and their structure was assigned on the basis of mono and bidimensional NMR experiments. Their inhibitory activity against acyl-CoA:cholesterol acyltransferase (ACAT) was tested on the enzyme prepared from rat liver microsomes. Theoretical studies were performed to correlate the activity of the compounds to their structural features.

PDF (162KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2719-2737
Published online:
DOI: 10.3987/COM-00-9051
Synthesis and Antitumor Activity of Non-Prodrug Water-soluble Taxoid: 10-C-Aminoalkylated Docetaxel Analogs

Shin Iimura, Satoru Ohsuki, Jun Chiba, Kouichi Uoto, Michio Iwahana, Hirofumi Terasawa, and Tsunehiko Soga*

*New Product Research Laboratories IV, Daiichi Pharmaceutical Co., Ltd., 1-16-13, Kitakasai, Edogawa, Tokyo 134-8630, Japan

Abstract

To develop non-prodrugs of taxoids possessing satisfactory stability in vivo, high water solubility and potent antitumor activity, we prepared several 10-C-sec-aminoalkylated docetaxel analogs and evaluated their cytotoxicity against mouse leukemia and human tumor cell lines. These analogs were synthesized from a 10-deacetoxy-10-C-formylethyl baccatin derivative. Among these analogs, the 10-C-morpholinoethyl and 10-C-morpholinomethyl analogs exhibited cytotoxicity comparable or superior to that of docetaxel.

PDF (125KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2739-2751
Published online:
DOI: 10.3987/COM-00-9052
Stereoselective Synthesis of 4(5)-[(2S,3S)- and (2R,3R)-3-Aminotetrahydrofuran-2-yl)imidazoles Using Modified and Standard Mitsunobu Cyclizations: Synthetic Studies toward Novel Histamine H3-Ligands

Shinya Harusawa, Ikuno Ijichi, Lisa Araki, and Takushi Kurihara*

*Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan

Abstract

4(5)-[(2S,3S)-3-Aminotetrahydrofuran-2-yl)imidazole [(+)-3] and its enantiomer [(-)-(2R,3R)-3] were stereoselectivity synthesized by using both modified and standard Mitsunobu cyclizations from L- and D-methionine, respectively.

PDF (118KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2753-2758
Published online:
DOI: 10.3987/COM-00-9057
An Efficient Synthesis of 1,2-Dithiolanes and 1,2,4-Trithiolanes by the Reaction of Phosphorus Ylides with Elemental Sulfur

Kentaro Okuma,* Kazuki Kojima, and Shinji Shibata

*Department of Chemistry, Faculty of Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan

Abstract

Reaction of diarylmethylenetriphenylphosphoranes with elemental sulfur followed by the addition of maleic anhydride afforded 1,2-dithiolanes in good yields. When the reaction was carried out in the presence of adamantane-2-thione, two types of 1,2,4-trithiolane were formed. Thiation of thiobenzo-phenones with elemental sulfur also afforded the corresponding 1,2-dithiolanes.

PDF (273KB)
Paper | Regular issue | Vol 53, No. 12, 2000, pp.2759-2768
Published online:
DOI: 10.3987/COM-00-9061
High Regio- and Stereoselectivity in Facile One-Pot Conversion of Taxoids to the Primary Alcohols: Precursors for the Synthesis of 4-Deacetoxypacilitaxel and Analogues

Qian Cheng, Tohru Horiguchi, Marina Yamaguchi, and Takayuki Oritani*

*Laboratory of Applied Bioorganic Chemistry, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan

Abstract

The conversion of alkali metal hydroxy base sensitive taxoids bearing ester groups to the corresponding primary alcohols in a facile one-pot protocol has been reported. This process which involves two steps of hydroboration and oxidation, using a mixture of NMO and TBHP (2:1), which possesses high regio- and stereoselectivity was first established. Proof of the chemistry used in the preparation of a precursor for the synthesis of a 4-deacetoxypaclitaxel analogue has also been presented.

PDF (243KB)
Note | Regular issue | Vol 53, No. 12, 2000, pp.2769-2773
Published online:
DOI: 10.3987/COM-00-9019
Indium-mediated Facile Synthesis of 3-Unsubstituted Ferrocenyl β-Lactams

Anjan Ghatak, Frederick F. Becker, and Bimal K. Banik*

*The University of Texas, M. D. Anderson Cancer Center, Department of Molecular Pathology, Box-089, 1515 Holcombe Blvd. , Houston, TX 77030, U.S.A.

Abstract

A simple synthesis of some 3-unsubstituted ferrocenyl β-lactams was achieved through indium mediated reaction of imines with ethyl bromoacetate

PDF (104KB)
Note | Regular issue | Vol 53, No. 12, 2000, pp.2775-2780
Published online:
DOI: 10.3987/COM-00-9024
Chemoselective Synthesis of Pyrazole Derivatives via β-Enamino Keto Esters

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

Abstract

β-Enamino keto ester (2a) reacts with hydroxylamine to give an isoxazole derivative (3). Compound (2a) reacts with hydrazine, alkyl- and arylhydrazines to give pyrazole derivatives (4a-e) as only reaction products. Methylation of compound (4a) afforded the two isomeric pyrazole derivatives (4b) and (5).

PDF (216KB)
Note | Regular issue | Vol 53, No. 12, 2000, pp.2781-2788
Published online:
DOI: 10.3987/COM-00-9029
Photochemistry of N-3-Butenyl- and N-4-Pentenylglutarimides: Intramolecular Thietane Formation and the Fission of Thietane Ring

Kazuaki Oda,* Takeshi Ishioka, Yuichi Fukuzawa, Naozumi Nishizono, and Minoru Machida*

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

Abstract

Intramolecular photoreaction of N-3- or N-4-alkenylthioglutarimides (two or three methylenes) gave thietanes and their fission products.

PDF (114KB)
Note | Regular issue | Vol 53, No. 12, 2000, pp.2789-2793
Published online:
DOI: 10.3987/COM-00-9032
Synthesis of the 4-Hydroxyimino-3-carboxamide-2-quinolone with a New Heterocyclization Mechanism of the Reaction between Carbon Suboxide and 2-Aminobenzamidoxime

Daniela Secci,* Franco Chimenti, Silvio M. Lavagna, Leonardo Bonsignore, Fedele Manna, Stefano Alcaro, and Adriana Bolasco

*Dipartimento Farmaco Chimico Tecnologico, Università degli Studi di Cagliari, Via Ospedale 72, 09124 Cagliari, Italy

Abstract

Synthesis of the 4-hydroxyimino-3-carboxamide-2-quinolone with a new heterocyclization mechanism of the reaction between carbon suboxide and 2-aminobenzamidoxime is reported. Its formation is also supported by charge calculations.

PDF (149KB)
Note | Regular issue | Vol 53, No. 12, 2000, pp.2795-2802
Published online:
DOI: 10.3987/COM-00-9045
Dammarane Triterpenoids from Amoora yunnanensis

Xiao-Dong Luo, Shao-Hua Wu, Yun-Bao Ma, and Da-Gang Wu*

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

Abstract

Four dammarane triterpenoids, 20S,24-epoxy-24,25-dihydroxydammar-3-one, 20S,23R,24R-23-chloro-20,24-epoxydammarane-3α,24,25-triol 3-acetate, 20S,23R,24S-23-chloro-20,24-epoxydammarane-3α,24,25-triol 3-acetate, and 20S,24-epoxy-24,25-dihydroxy-3,4-secodammar-4(28)-en-3-oic acid, in addition to eight known dammarane triterpenoids, 3-acetylcabraleadiol, cabraleadiol, cabralea-hydroxylactone, ocotillone, cabraleone, 24,25-dihydroxy-dammar-20-en-3-one, shoreic acid, and 20S,24-epoxy-25,26,27-trisnor-24-oxo-3,4-secodammar-4(28)-en-3-oic acid, were isolated from the bark of Amoora yunnanensis. Their structures were elucidated by a combination of 1D and 2D NMR spectral analysis and comparison with closely related compounds

PDF (67KB)
Note | Regular issue | Vol 53, No. 12, 2000, pp.2803-2808
Published online:
DOI: 10.3987/COM-00-9046
Sythesis of 2-(2-Alkoxycarbonylphenylthio)-1,2-benzisothiazolin-3-ones from 2-Sulfenamoylbenzoates

Masao Shimizu,* Toshiyuki Takagi, Motonari Shibakami, Yasuo Gama, and Isao Shibuya

*National Institute of Material and Chemical Research, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan

Abstract

The Mechanism of formation of 2-(2-alkoxycarbonylphenylthio)-1,2-benzisothiazolin-3-ones, which were obtained by the heating of 2-sulfenamoylbenzoates, was investigated. It appears that transamination occurred on the sulfur atom of a 2-sulfenamoylbenzoate between the amino group and the 1,2-benzisothiazolin-3-one, which formed by the cyclization of methyl 2-sulfenamoylbenzoate after heating, to give 2-(2-methoxycarbonylphenylthio)-1,2-benzisothiazolin-3-ones. Several types of 2-sulfenyl-1,2-benzisothiazolin-3-ones were synthesized from the 2-sulfenamoylbenzoates.

PDF (38KB)
Note | Regular issue | Vol 53, No. 12, 2000, pp.2809-2819
Published online:
DOI: 10.3987/COM-00-9049
Synthesis and Chemiluminescent Activity of Pyridazino[4,5-b]indole-
1,4(2H,3H)-diones

Masateru Kurumi, Kenji Sasaki,* Hiroko Takata, and Taiji Nakayama

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

Abstract

Substituted and non-substituted anilines were transformed to the corresponding triazole derivatives, which were converted to dimethyl indole-2,3-dicarboxylates by photocyclization. The reaction of diester with hydrazine hydrate gave 1,2,3,4-tetrahydro-5H-pyridazino[4,5-b]indole-1,4(2H,3H)-diones (5). Some of compounds (5) were found to have chemiluminescent activity in a similarly to luminol in the presence of hydrogen peroxide and peroxidase in a basic solution.

PDF (388KB)
24 data found. 1 - 24 listed