Regular Issue

Vol. 51, No. 12, 1999

23 data found. 1 - 23 listed
Communication | Regular issue | Vol 51, No. 12, 1999, pp.2801-2806
Published online:
DOI: 10.3987/COM-99-8685
A New Method for the Conversion of Hexose Derivatives into Substituted Pyrrolidines

Cedric W. Holzapfel,* Renier Crous, Hendrik F. Greyling, and Gerhard H. Verdoorn

*Department o f Chemistry and Biochemistry, Rand Afrikaans University, P.O. Box 524, Auckland Park, 2006, Johanesberg, South Africa

Abstract

The consecutive reduction and cyclisation of O-benzoyl protected 5-O-mesyihexose O-(tert-butyldiphenylsilyl)oximes to afford chiral N-hydroxypyrrolidines is discussed. The mechanism involves a cascade of neighboring group participation steps involving the O-benzoyl protecting groups. This protocol gave rise to new chiral N-hydroxypyrrolidines in good overall yield.

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Communication | Regular issue | Vol 51, No. 12, 1999, pp.2807-2813
Published online:
DOI: 10.3987/COM-99-8692
Syntheses and Properties of Calixarene Analogs Containing Thiophene Ring

Kazuaki Ito,* Yoshihiro Ohba, Takafumi Tamura, Tomoaki Ogata, Hajime Watanabe, Yasumitsu Suzuki, Takayuki Hara, Yukou Morisawa, and Tyo Sone

*Department of Materials Science and Engineering, Faculty of Engineering, Yamagata University, 4-3-16 Jyonan, Yonezawa 992-8510, Japan

Abstract

Calixarene analogs containing a thiophene unit in the macrocyclic ring were prepared by a stepwise method. The macrocycles adopt a cone-like form as the preferred conforniation in solution. The induced chemical shift change, NOE experiment, and relaxation time (T1) measurement supported the fact that the macrocycle forms a complex with the N-methylpyridinium salt.

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Communication | Regular issue | Vol 51, No. 12, 1999, pp.2815-2821
Published online:
DOI: 10.3987/COM-99-8721
A Novel Methodology for Preparing 5-Chloro- and 5-Bromotryptamines and Tryptophanes, and Its Application to the Synthesis of (±)-Bromochelonin B

Masakazu Hasegawa, Koji Yamada, Yoshiyuki Nagahama, and Masanori Somei*

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

Abstract

A novel methodology for introducing chlorine or bromine into the 5-position of tryptamines was found through 1-hydroxytryptamines. The chemistry was applied to the syntheses of (±)-5-chloro-, -5-bromotryptophan derivatives, and (±)-bromochelonin B.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2823-2847
Published online:
DOI: 10.3987/COM-98-8315
Regiospecific Functionalization of Indole-2-carboxylates and Diastereoselective Preparation of the Corresponding Indolines

Valérie Collot, Martine Schmitt, Padma Marwah, and Jean-Jacques Bourguignon*

*Laboratoire de Pharmacochimie de la Communication Cellulaire, ERS 655, Faculte de Pharmacie, Université Louis Pasteur, 74, route du Rhin, BP 24, 67401 ILLKIRCH Cedex, France

Abstract

The N-acyl derivatives of 3-substituted indole-2-carboxylates prepared through several routes were submitted to catalytic hydrogenation affording either cis- or trans-indoline diastereomers after quantitative C-2 epimerization.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2849-2854
Published online:
DOI: 10.3987/COM-99-8636
Efficient Method for the Synthesis of Bisaminoethanethiols and Their Pyrrole Conjugates

Guolin Li, Qinggago Ma, Bing Ma, Zachary D. Grossman, and Ravindra K. Pandey*

*Photodynamic Therapy Center, Roswell Park Cancer Institute, Buffaolo, NY 14263, U.S.A.

Abstract

By following the protection and deprotection approach, an efficient method for the preparation of bisaminoethanethiol ligands (N2S2) is discussed. In our attempts to synthesize certain nonpeptide analogs of neurotensin, moldel studies were performed by using these ligands for preparing the corresponding pyrrole based conjugates. This methodology provides an alternate approach for developing various target specific agents that cross the blood brain barrier.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2855-2860
Published online:
DOI: 10.3987/COM-99-8637
Synthesis of N2S2 Conjugates of the Highly Specific Mitochondrial Diazapam Binding Inhibitor (DBI) Receptor Complexes

Guolin Li, Bing Ma, Joseph R. Missert, Zachary D. Grossman, and Ravindra K. Pandey*

*Photodynamic Therapy Center, Roswell Park Cancer Institute, Buffaolo, NY 14263, U.S.A.

Abstract

A novel approach for the synthesis of N2S2 ligands conjugated with 2-phenylindole analogs known as mitochondrial diazapam binding inhibitor receptor complexes (previously known as peripheral-type benzodiazepine receptor), as possible target specific Tc-99m imaging agents is described.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2861-2870
Published online:
DOI: 10.3987/COM-99-8657
The 1,4-Dithiin Ring Opening in 1,4-Dithiinodiquinolines as a Route to Quinoline Crown Thioethers

Krystian Pluta

*Department of Organic Chemistry, The Medical University of Silesia, Jagiellonska Str. 4, 41-200 Sosnowiec, Poland

Abstract

Quinoline crown thioethers (7) and (8) with 8-, 9-, 10-, 11-, 12-, 18-, 20-, 21- and 24-membered macrocyclic thiacrown ring were obtained by the 1,4-dithiin ring opening in 1,4-dithiinodiquinolines (1) and (2) with divalent sulfur nucleophiles followed by S-alkylation with divalent alkylating agents. Thiacrowns (7) and (8) contain two or four quinoline units.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2871-2879
Published online:
DOI: 10.3987/COM-99-8681
Pictet-Spengler Reaction of Biogenic Amines with (2R)-N-Glyoxyloylbornane-10,2-sultam. Enantioselective Synthesis of (S)-(+)-N-Methylcalycotomine and (R)-(+)-Xylopinine

Zbigniew Czarnocki* and Zbigniew Arazny

*Department of Chemistry, University of Warsaw, Pasteura St.1, 02-093 Warsaw, Poland

Abstract

The Pictet-Spengler reaction of (2R)-N-glyoxyloylbornane-10,2-sultam with dopamine hydrochloride gave the condensation product, which was further converted into (S)-(+)-N)-methylcalycotomine and (R)-(+)-xylopinine of high enantiomeric purity.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2881-2892
Published online:
DOI: 10.3987/COM-99-8688
CAN-mediated Formation of Furopyranones and Furoquinolinones

Kazuhiro Kobayashi,* Kouji Sakashita, Hideki Akamatsu, Koujirou Tanaka, Masaharu Uchida, Tomokazu Uneda, Taichi Kitamura, Osamu Morikawa, and Hisatoshi Konishi

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

Abstract

The reaction of 4-hydroxy-2H-pyran-2-one derivatives (1), (11), and (17) with a range of alkenes or phenylacetylene in acetonitrile containing cerium(IV) ammoniurn nitrate (CAN) afforded the corresponding furo[3,2-c]pyranone (4, 8, 13, 15, and 18) and/or furo[2,3-b]pyranone derivatives (6, 10, 14, 16, and 19). Similar treatment of 4-hydroxy-1-methylquinolin-2(1H)-one (2) with alkenes or phenylacetylene in the presence of CAN gave furo[3,2-c]quinolin-4(5H)-one derivatives (5) and (9).

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2893-2905
Published online:
DOI: 10.3987/COM-99-8696
Syntheses and Structure Elucidation of Dimethylaminovinyl Substituted 1,3-Oxazines and Pyrazolo[3,4-d][3,1]oxazine Derivatives

Zhijun Wang, Walter Kramer, and Richard Neidlein*

*Pharmazeutisch-Chemishces Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany

Abstract

Potassium methyl dicyanoacetate (1) reacted with (3,3-dichloro-2-propenylidene)dimethylammonium chloride (2) to yield a mixture (1:1) of E- and Z-4-chloro-5-cyano-2-(N,N-dimethylimmonio)ethyliden-6-oxido-1,3-oxazines (3) which reacted further with different amines and aryihydrazines to 1,3-oxazine and pyrazolo[3,4-d][3,1]oxazine derivatives respectively. The products exist surprisingly only as E- configuration. The structures were elucidated unambiguously with a X-Ray diffraction analysis and NMR experiments.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2907-2914
Published online:
DOI: 10.3987/COM-99-8701
Diastereoselective Alkylation of Aromatic Enamidone Functionality in Isoindole Series: A Convenient Route to Chiral Aza-analogues of Senkyunolide-E

Abderrahim Chihab Eddine, Adam Daïch,* Abderrahim Jilale, and Bernard Decroix

*Laboratoire de Chimie, URCOM, Faculté des Sciences et Techniques, Université du Havre, 25 Rue Philippe Lebon, B.P. 540 76058 Le Havre Cedex, France

Abstract

Chiral aza-analogues (2a) and (2b) of Senkyunolide-E were efficiently synthesized in a four-step sequence (72 and 70 % overall yields respectively) from the commercially available phthalic anhydride and (S)-(-)-α-phenylethylamine. The key step consisted in the 1,2-addition of Grignard reagents onto enamidone type compounds (8) and (9). These latters were regioselectively obtained from the parent ω-alkynyl-ω-carbinol lactams (6) and (7) by a Meyer-Schuster rearrangement.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2915-2930
Published online:
DOI: 10.3987/COM-99-8712
Synthesis and Antibacterial Activity of Novel 7-Substituted 6-Fluoro-1-methylene-4-oxo-4H-[1,3]thiazeto[3,2-a]quinoline-3-carboxylic Acid Derivatives

Masato Matsuoka,* Jun Segawa, Isao Aminoto, Yasushi Masui, Yoshifumi Tomii, Masahiko Kitano, and Masahiro Kise

*Research Laboratories, Nippon Shinyaku Co., Ltd., 14, Nishinosho-Monguchi-cho, kisshoin, Minami-ku, Kyoto, 601-8550, Japan

Abstract

A series of 7-substituted 6-fluoro-1-methylene-4-oxo-4H-[1,3]thiazeto[3,2-a]quinoline-3-carboxylic acid derivatives (2) and (3) was prepared and evaluated for antibacterial activity. These compounds were obtained by the treatment of the 1-methanesulfonyloxymethyl or 1-fluoromethyl thiazetoquinolone-3-carboxylates (12, 14 and 20) with potassium hydroxide. Compounds (2) and (3) showed excellent in vitro antibacterial activity against both gram-negative and gram-positive bacteria including quinolone and Methicillin-resistant Staphylococcus aureus.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2931-2940
Published online:
DOI: 10.3987/COM-99-8716
Generality and Scope of the Synthesis of 2-Arylpyrrolo[3,4-b]quinoxaline-1,3-diones from 2,3-Dichloro-N-arylmaleimides. II

Leila Hanaineh-Abdelnour* and Badr A. Salameh

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

Abstract

Nucleophilic substitution of 2,3-dichloro-N-arylmaleimides (1) and (2) with a series of arylamines gives 2-arylamino-3-chloro-N-arylmaleimides (3) and (4), respectively. When 4 is treated with sodium azide at room temperature, it cyclizes to the 2-(p-methoxyphenyl)pyrrolo[3,4-b]quinoxaline-1,3-diones (5). Under the same conditions, the 2-(p-nitrophenyl) analogue (3) fails to cyclize. Ring closure is also subject to the steric and electronic effects of substituents in the nucleophile.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2941-2948
Published online:
DOI: 10.3987/COM-99-8718
Novel Zinc Mediated Indole Ring Opening of Isoreserpine

Mathias Berner, Arto Tolvanen, Mauri Lounasmaa,* and Reija Jokela*

*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, P.O. Box 6100, FIN-02150 HUT Espoo, Finland

Abstract

Reaction of reserpine (1) with Zn/TFA resulted in isoreserpine (2), dihydro compound (7), and amino compound (8) via initial epimerization at C-3. The latter two compounds constitute a novelty in indole alkaloid chemistry: the dihydro compound (7) possesses unusual H-2/H-7 cis and H-2/H-3 trans relationships, whereas the amino compound (8) displays a novel zinc mediated indole ring scission.

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Paper | Regular issue | Vol 51, No. 12, 1999, pp.2949-2960
Published online:
DOI: 10.3987/COM-99-8733
Degradational Cyclization of α-[2-Phenyl-2-(phenylsulfonylhydrazono)ethyl]phenacylidenetriphenylphosphoranes to 3,6-Diphenylpyridazines and 5-Benzoyl-3-phenylpyrazoles

Suketaka Ito,* Akikazu Kakehi, and Kyoko Okada

*Depatment of Indusrial Chemistry, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan

Abstract

α-[2-Phenyl-2-(phenylsulfonylhydrazono)ethyl]phenacylidenetriphenyiphosphoranes were obtained (60-71%) by the reaction between phenylsulfonylhydrazones of phenacyl bromides and phenacylidenetriphenylphosphoranes. Thermolysis of the phosphoranes gave 3,6-diphenylpyridazines (43-66%) and 5-benzoyl-3-phenylpyrazoles (13-27%), together with triphenylphosphine oxide and S-phenyl benzenethiosulfonate, a disproportionation product from benzenesulfinic acid. The structure of the intermediate α-substituted phenacylidenetriphenylphosphorane was confirmed by an X-Ray diffraction method.

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Note | Regular issue | Vol 51, No. 12, 1999, pp.2961-2967
Published online:
DOI: 10.3987/COM-99-8615
Synthesis and Structure Determination of N,N-Diethyl-3-[3-aryl-1,2,4-oxadiazol-5-yl]propionamides

Rajendra Mohan Srivastava,* Maria da Conceição Pereira, Fernando Hallwass, and Carlos R. N. Pacheco

*Departamento de Química Fundamental, Centro de Ciências Exatas e da Natureza, Universidade Federal de Pernambuco, Cidade UniversitÁria, CEP 50.670-901, Recife - PE, Brazil

Abstract

An efficient and facile synthesis of six new 1,2,4-oxadiazoles (6a-f) with a tertiary amide group attached on the side-chain, in high yield, is described. Correct assignments of side-chain methylene, methyl protons, and carbon signals have been made with the assistance of COSY, NOESY and HETCOR NMR experiments.

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Note | Regular issue | Vol 51, No. 12, 1999, pp.2969-2976
Published online:
DOI: 10.3987/COM-99-8679
Four New Styryllactones form Goniothalamus leiocarpus

Qing Mu, Weidong Tang, Chaoming Li,* Yang Lu, Handong Sun, Huilan Zheng, Xiaojiang Hao, Qitai Zheng, Nan Wu, Liguang Lou, and Bin Xu

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

Abstract

Four new styryllactones, leiocarpin A (1), 7-epi-goniodiol (2), leiocarpin B (3) and leiocarpin C (4), respectively, were isolated from the stem bark of Goniothalamus leiocarpus. Their structures were elucidated by means of spectral method. The relative configurations of 1, 2 and 3 were determined by X-Ray crystallographic analysis. Compounds 2 and 3 possess antitumor activities.

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Note | Regular issue | Vol 51, No. 12, 1999, pp.2977-2982
Published online:
DOI: 10.3987/COM-99-8682
A Preparative Route to Fused Indeno[1,2-e][1,2,4]triazolo[4,3-a]pyrazin-4-ones

Yves Ribeill, Arielle Genevois-Borella, Marc Vuilhorgne, and Serge Mignani*

*Rhone-Poulene-Rorer, Centre de Recherche de Vitry-Alfortville, 13 Quai Jules Guesde, 94403 Vitry sur Seine, France

Abstract

Syntheses of new fused indeno[1,2-e][1,2,4]triazolo[4,3-a]pyrazin-4-one derivatives (1a-g) starting from 1-indanone are described.

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Note | Regular issue | Vol 51, No. 12, 1999, pp.2983-2989
Published online:
DOI: 10.3987/COM-99-8699
Synthesis of Optically Active 2-Piperidylglycine

Hyun-kyu Chung, Hyung-woo Kim, and Kyoo-Hyun Chung*

*Department of Chemistry, Inha University, 253, Yonghyundong Namgu, Inchon 402-751, Korea

Abstract

Both chiral threo- and erythro-2-piperidylglycines were synthesized from racemic 2-[(N-benzyloxycarbonyl)piperidin-2-yl]ethanoic acid. (4S,5S)-4-Methyl-5-phenyl-2-oxa-zolidinone was used as a chiral auxiliary in the resolution and azidation.

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Note | Regular issue | Vol 51, No. 12, 1999, pp.2991-3000
Published online:
DOI: 10.3987/COM-99-8700
3-Triphenylphosphoranylideneamino-2-cycloalkenones: Reaction with Methyl Propiolate Leading to [n](2,6)-Pyridinophanes

Hiroyuki Yamamoto, Minako Yuasa, and Makoto Nitta*

*Department of Chemistry, School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan

Abstract

The title compounds have been synthesized, and their reaction with methyl propiolate afforded 3-methoxycarbonyl[n](2,6)-pyridinophanes (n=9 and 8), along with 5,6-ring annulated 2-methoxypyridines albeit in low yields, respectively.

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Note | Regular issue | Vol 51, No. 12, 1999, pp.3001-3004
Published online:
DOI: 10.3987/COM-99-8704
A Lupin Alkaloid, (-)-Tenuamine (Norlusitanine), from Maackia tenuifolia

Yong-Hong Wang, Kimio Higashiyama, Hajime Kubo, Jia-Shi Li, and Shigeru Ohmiya*

*Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan

Abstract

A lupin alkaloid, (-)-tenuamine, was isolated from the stem parts of Maackia tenuifolia together with eight known alkaloids. The structure of (-)-tenuamine was determined to be (-)-acetylaminomethylideneindolizidine by comparison of its chemical and spectroscopic data with those of (-)-lusitanine, (+)-tashiromine and indolizidine.

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Note | Regular issue | Vol 51, No. 12, 1999, pp.3005-3012
Published online:
DOI: 10.3987/COM-99-8706
A Facile Synthesis of 1,2-Benzisothiazolin-3-ones from Thiosalicylates

Masao Shimizu,* Hisashi Kikumoto, Takeo Konakahara, Yasuo Gama, and Isao Shibuya

*National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan

Abstract

Synthesis of 1,2-benzisothiazolin-3-ones by cyclization of 2-sulfenamoylbenzoates, which were prepared from amination of thiosalicylates by hydroxylamine-O-sulfonic acid, was examined. Although treatment of methyl 2-sulfenamoylbenzoate on heating gave unexpected 2-(2-methoxycarbonylphenylthio)-1,2-benzisothiazolin-3-one, the treatment with base at room temperature afforded the corresponding 1,2-benzisothiazolin-3-ones in good yields.

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Review | Regular issue | Vol 51, No. 12, 1999, pp.3013-3030
Published online:
DOI: 10.3987/REV-99-524
Base-catalysed Rearrangements of 5-Oxodihydroisoxazoles

Rolf H. Prager* and Craig M. Williams

*Chemistry Department, Flinders University of South Australia, G.P.O.Box 2100, Adelaide 5001, Australia

Abstract

Five distinct pathways for the reaction of isoxazol-5(2H)-ones with bases or nucleophiles have been reported, and are detailed herein. That investigated in greatest detail, and of greatest application in heterocyclic synthesis, is that of isoxazolones unsubstituted at C-3, in which the sequentially formed ketenimine, α-lactone and ketene may all react with a nucleophile.

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23 data found. 1 - 23 listed