Regular Issue

Vol. 68, No. 3, 2006

13 data found. 1 - 13 listed
Communication | Regular issue | Vol 68, No. 3, 2006, pp. 453 - 457
Published online: 21st February, 2006
DOI: 10.3987/COM-05-10661
Novel Method for the Synthesis of β-Lactams by the Reaction of α-Bromocarboxylic Acids with Imines Mediated by Triphenylphosphine

Satoshi Kikuchi and Yukihiko Hashimoto*

*Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan


The useful and simple method for the formation of the β-lactams by the reaction between α-bromo carboxylic acids and imines is described. This reaction was effectively mediated by triphenylphosphine or polystyryl-diphenylphosphine to give the β-lactams in good yields with high trans-selectivity.

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Communication | Regular issue | Vol 68, No. 3, 2006, pp. 459 - 463
Published online: 14th February, 2006
DOI: 10.3987/COM-06-10689
A Novel and Efficient Darzens Reaction Catalyzed by Magnesium Bromide

Shigeki Sano, Motoyuki Miyamoto, Tomoko Mitani, and Yoshimitsu Nagao*

*Faculty of Pharmaceutical Sciences, University of Tokushima, Sho-machi, Tokushima 770-8505, Japan


The Darzens reaction of phenacyl bromide with aromatic aldehydes catalyzed by MgBr2 in the presence of an excess amount of triethylamine afforded trans-α,β-epoxy ketones in good yields.

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Paper | Regular issue | Vol 68, No. 3, 2006, pp. 465 - 474
Published online: 14th February, 2006
DOI: 10.3987/COM-05-10568
Synthesis and X-Ray Crystal Structure Determinations of Pyrrolidine-2,4-diones, 2-Iminopyrrolidin-5-ones and 1,3-Oxazine-2,4-diones Derived from Acetoacetanilides

Thomas Duff, John P. James,* and Helge Müller-Bunz

*School of Chemical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland


Commercially available acetoacetanilides may, after initial alkylation, be cyclized to pyrrolidine-2,5-diones by reaction with ethyl bromoacetate or cyclized to 5-iminopyrrolidin-2-ones with chloroacetonitrile. Reaction with ethyl chloroformate gives 1,3-oxazine-2,4-diones. Several examples of these reactions using different alkyl groups are described. The structures of the products were confirmed by X-Ray crystallography.

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Paper | Regular issue | Vol 68, No. 3, 2006, pp. 475 - 481
Published online: 17th January, 2006
DOI: 10.3987/COM-05-10619
Copper Catalyzed Cyclopropanation of 1,2,3,4-Tetrahydropyridin-2-ones with Trimethylsilyldiazomethane: A Facile and Selective Synthesis of 2-Aza-3-oxobicyclo[4.1.0]heptanes

Vishal B. Sharma, Suman L. Jain, and Bir Sain*

*Chemical and Biotechnology Division, Indian Institute of Petroleum, Dehradun-248005, India


The reactions of a series of 1,2,3,4-tetrahydropyridin-2-ones with trimethylsilyldiazomethane using catalytic amounts of copper(II) triflate in refluxing 1,2-dichloroethane yielded exclusively 3-oxo-2-azabicyclo[4.1.0]heptanes in good yields. The application of ultrasonic radiation enhanced the reaction rate and allowed the reactions to be conducted at room temperature.

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Paper | Regular issue | Vol 68, No. 3, 2006, pp. 483 - 493
Published online: 31st January, 2006
DOI: 10.3987/COM-05-10652
Asymmetric Synthesis of Flindersiachromanone Using Lipase-catalyzed Reaction

Masashi Kawasaki,* Hikaru Yoshikai, Hiroko Kakuda, Naoki Toyooka, Akira Tanaka, Michimasa Goto, and Tadashi Kometani

*Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan


The (R)- and (S)-enantiomers of flindersiachromanone (2-(2-phenylethyl)-4-chromanone) were synthesized from the enantiomerically pure 1-phenyl-5-hexen-3-ol obtained via the lipase-catalyzed enantioselective transesterification.

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Paper | Regular issue | Vol 68, No. 3, 2006, pp. 495 - 503
Published online: 21st February, 2006
DOI: 10.3987/COM-05-10654
1-Alkyl-4-(3-pyridinylamino)quinolinium-3-thiolates and Their Transformation into New Diazaphenothiazine Derivatives

Andrzej Zieba* and Kinga Suwinska

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


The reactions of 5,12-dialkylthioquinantrenediinium bis-salts (1) with 3-aminopyridine yield 1-alkyl-4-(3-pyridinylamino)quinolinium-3-thiolates (2). In the presence of oxygen and hydrogen chloride, the compounds (2) undergo cyclization to 1,4-thiazine derivatives having the structure of 5-alkyl-12(H)-pyrido[2,3-e]quino[3,4-b][1,4]thiazinium salts (4). The structure of 3-thiolates (2) was analyzed using 1H NMR (NOE) and 15N NMR spectral methods. The structure of compound (4) was confirmed by X-Ray analysis.

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Paper | Regular issue | Vol 68, No. 3, 2006, pp. 505 - 513
Published online: 14th February, 2006
DOI: 10.3987/COM-05-10659
1-Allylation of 2-Benzotelluropyrylium Salts and 2-Benzoselenopyrylium Salts by Means of Allyltin Reagents

Kazuo Ohyanagi and Haruki Sashida*

*Faculty of Pharmaceutical Sciences, Hokuriku University, 3-Ho, Kanagawa machi, Kanazawa 920-1181, Japan


3-tert-Butyl-2-benzotelluropyrylium salt (1) reacts with an equal amount of allyltributyltin to afford 1-allyl-3-tert-butyl-1H-isotellurochromene (8a) in 93 % yield. Similarly, 1-allyl-1H-isotellurochromenes (9) and isoselenochromenes (10, 11) were prepared from the corresponding pyrylium salts (2-4) in moderate to good yields.

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Paper | Regular issue | Vol 68, No. 3, 2006, pp. 515 - 520
Published online: 14th February, 2006
DOI: 10.3987/COM-06-10674
Synthesis of Cribrostatin 6 and Its Related Compounds

Shinsuke Nakahara,* Akinori Kubo, Yuzuru Mikami,* and Junji Ito

*Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan


The synthesis of cribrostatin 6 (1), which shows good biological activity as a dark blue cancer cells growth inhibitor and a number of pathogenic bacteria and fungi, was achieved in two steps from 1-acetylaminomethyl-5,7-diethoxy-8-hydroxy-6-methylisoquinoline (14). The related compounds (8~11) were also synthesized, and the antimicrobial activities of 1 and its nine related compounds (5~13) were investigated.

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Note | Regular issue | Vol 68, No. 3, 2006, pp. 521 - 530
Published online: 14th February, 2006
DOI: 10.3987/COM-05-10639
Synthesis of 2’-O-Methyl-5-alkynyl and alkenyl Substituted Uridine Derivatives to Screen for Inhibitors of HCV

Yili Ding,* Jean-Luc Girardet, Zhi Hong, Stephanie Z. Shaw, and Nanhua Yao

*Drug Discovery, Valeant Pharmaceuticals International, Inc., 3300 Hyland Avenue, Costa Mesa, CA 92626, U.S.A.


Using Sonogashira and Heck coupling reactions, a series of 5-alkynyl and 5-alkenyl substituted 2’-O-methyluridine derivatives were synthesized in high yields. These compounds were used to screen for inhibitors of HCV, however none of them showed significant HCV inhibitory activity under 300 μM.

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Note | Regular issue | Vol 68, No. 3, 2006, pp. 531 - 537
Published online: 21st February, 2006
DOI: 10.3987/COM-05-10642
7-(Imidazolidin-1-ylmethyl)quinolin-8-ol: An Unexpected Product from a Mannich-Type Reaction in Basic Medium

Augusto Rivera,* Jaime Ríos-Motta, and Miguel Angel Navarro

*Departamento de Química, Universidad Nacional de Colombia, Ciudad Universitaria, Carrera 30 # 45-03, Bogotá, Colombia


7-(Imidazolidin-1-ylmethyl)quinoline-8-ol, an N-substituted imidazolidine, was synthesized in a one-step reaction between 1,3,6,8-tetraazatricyclo[]dodecane (TATD) and 8-hydroxyquinoline. Obtaining this substance enhanced the scope of possibilities in the synthesis of unsymmetrically N,N-disubstituted imidazolidines. 1H-NMR spectral studies revealed that this type of substance does not undergo ring-chain tautomerism.

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Note | Regular issue | Vol 68, No. 3, 2006, pp. 539 - 547
Published online: 14th February, 2006
DOI: 10.3987/COM-05-10651
Unexpected 7-Methylation of Oxindoles

Balázs Volk,* Rita Kapiller-Dezsöfi, and Gyula Simig

*Chemical Research Deivision, EGIS Pharmaceuticals Ltd., P.O.Box 100, H-1475 Budapest, Hungary


A unique, regioselective 7-methylation reaction has been discovered during the reductive 3-alkylation of isatin with i-BuOH at 230 °C, in the presence of Raney nickel, under hydrogen atmosphere. Based on this observation, a synthetic method has been elaborated for the preparation of 3-alkyl-7-methyloxindoles.

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Note | Regular issue | Vol 68, No. 3, 2006, pp. 549 - 559
Published online: 21st February, 2006
DOI: 10.3987/COM-06-10668
High-yielding Microwave Assisted Synthesis of Quinoline and Dihydroquinoline Derivatives under Solvent-free Conditions

D. Subhas Bose* and Racherla Kishore Kumar

*Organic Chemistry Division III, Fine Chemicals Laboratory, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500 007, India


A mild and efficient solvent-free method has been developed by two different approaches for the synthesis of quinoline and dihydroquinoline derivatives: (i) one-pot reaction of anilines with alkyl vinyl ketones (Skraup reaction) (ii) between various acetophenones and 2-aminoacetophenone (Friedländer reaction) using stable and effective heterogeneous catalyst potassium dodecatangestocobaltate (25 mol %) (PDTC) under microwave irradiation in high yields.

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Review | Regular issue | Vol 68, No. 3, 2006, pp. 561 - 603
Published online: 28th February, 2006
DOI: 10.3987/REV-05-604
Pyrimidine Chemistry in Crop Protection

Clemens Lamberth

*Chemistry, Crop Protection Research, Syngenta AG, Schwarzwaldallee 215, CH-4002 Basel, Switzerland


This review aims to give an overview of the significance of pyrimidine derivatives in crop protection. The main herbicidally, fungicidally and insecticidally active pyrimidine classes are presented, together with their synthetic routes, their modes of action and their biological efficacies. Quinazolines and other bicyclic pyrimidine derivatives are also covered.

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13 data found. 1 - 13 listed