Regular Issue

Vol. 75, No. 3, 2008

16 data found. 1 - 16 listed
Review | Regular issue | Vol 75, No. 3, 2008, pp. 493 - 529
Published online: 20th November, 2007
DOI: 10.3987/REV-07-620
Organocatalytic Asymmetric Synthesis Using Proline and Related Molecules. Part 1

Hiyoshizo Kotsuki,* Hideaki Ikishima, and Atsushi Okuyama

*Laboratory of Natural Product Chemistry, Faculty of Science, Kochi University, Akebono-cho, Kochi 780-8520, Japan


Organocatalytic asymmetric synthesis has been extensively studied and several important procedures for preparing optically active organic compounds have been developed. Research in this area has progressed rapidly in the last ten years. This review addresses the most significant advances in asymmetric synthesis using proline and related chiral organocatalysts mainly focusing on aldol reactions from the viewpoint of synthetic interests. This includes (1) proline-catalyzed aldol reactions, (2) proline-related chiral catalysts, and (3) other types of amino acid catalysts.

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Communication | Regular issue | Vol 75, No. 3, 2008, pp. 531 - 536
Published online: 16th November, 2007
DOI: 10.3987/COM-07-11226
Synthesis and Spectroscopic Properties of 2,5-Bis(benzoazol-2-yl)pyrazines

Ryota Saito,* Shinnosuke Machida, Saori Suzuki, and Akira Katoh

*Department of Materials and Life Science, Seikei University, 3-3-1 Kichijoji-kitamachi, Musashino, Tokyo 180-8633, Japan


A class of p-conjugated 2,5-bis(benzoazol-2-yl)pyrazine dyes have been synthesized in which 2,5-bis(benzimidazol-2-yl)pyrazine (1) exhibits strong fluorescence in solution. The enhanced fluorescence of 1 with a base leads to future applications such as anion sensing feasible upon chemical modification.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 537 - 554
Published online: 16th November, 2007
DOI: 10.3987/COM-07-11231
A Facile Synthesis of 4-Aryl-5-alkoxycarbonyl-6-hydroxy-6-methyl-4,5,6,7-tetrahydro-3-hydroxy-2-(pyridin-2-yl)indazoles and Their NMR Characterizations

Shanmugasundaram Amirthaganesan, Gopalakrishnan Aridoss, Young Hwan Park, Jong Su Kim, Se Mo son, and Yeon Tae Jeong*

*Division of Mage and Information Engineering, Pukyong National University, Busan 608-739, Korea


A series of N-pyridinyl tetrahydroindazoles have been synthesized by a convenient and regioseletive method by taking cyclic β-ketoesters as scaffolds. An optimum reaction condition was achieved by monitoring the reaction in different reaction condition. One and two dimensional NMR spectroscopic investigations evidenced the formation and structure of the compounds. Besides, all the compounds have been achieved as a single isomer with pyridyl group at N(2). A suitable reaction mechanism was proposed.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 555 - 569
Published online: 16th November, 2007
DOI: 10.3987/COM-07-11232
Synthesis of the Azathioprine Analogs

Alicja Kowalska* and Krystina Pluta

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


The effective synthesis of the azathioprine analogs - 2-subsituted derivatives of 7-methyl-6-(1-methyl-4-nitroimidazol-5-ylthio)purines 5 has been achieved by the reaction of 2-subsituted 6-purinethiones 4 with 5-chloro-1-methyl-4-nitroimidazole in ethanol. In the case of 7-methyl-2,6-dithioxanthine 4j, reaction in DMF gave di(imidazolyl) product 5l. The key step in this synthesis was preparation of the appropriate 2-substituted 6-purinones 2 and 6-chloropurines 3 which were further converted to 6-purinethione 4.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 571 - 576
Published online: 4th December, 2007
DOI: 10.3987/COM-07-11236
Reaction of 1,3-Oxathiin-6-ones with Bases: Synthesis of 4-Mercapto-2-pyrone

Kentaro Okuma* and Masahiro Koda

*Department of Chemistry, Fukuoka University, Jonan-ku, Fukuoka 814-0180, Japan


The reaction of 4-aryl-1,3-oxathiin-6-one 3,3-dioxide 3c with secondary amine gave cinnamamides 6 and ammonium sulfinates 7. On the other hand, the reaction of 4-methyl-1,3-oxathiin-6-one 1b with LDA, followed by the addition of benzoyl chloride, gave corresponding phenacyldioxenone 8a and 5-benzoyl-4-methyl-1,3-thiodioxenone 9 in nearly 1:1 ratio, whereas the reaction with 1-benzoyl-1,2,3-benzotriazole gave only 8a in 78% yield. Thermolysis of 8a gave the corresponding 4-mercapto-2-pyrone 4a in 62% yield.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 577 - 582
Published online: 30th November, 2007
DOI: 10.3987/COM-07-11239
Pyrolytic Study of Cyclic 2-Azidoketones

Chin-Hsing Chou,* Li-Tse Chu, I-Ying Chen, and Bo-Jian Wu

*Department of Chemistry and Center for Nanoscience and Nanotechnology, National Sun Yat-Sen University, Kaohsiung, 804, Taiwan, R.O.C.


Flash vacuum pyrolysis of 2-azidocyclohexanone (1) gave a condensed dimer (6), a ring expanded product (7) and 2-methylpyridine (8). On the other hand, pyrolysis of 2-azidocyclopentanone (4) and 2-azido-cycloheptanone (5) gave ring expanded products (12) and (13), respectively, as the main products.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 583 - 597
Published online: 7th December, 2007
DOI: 10.3987/COM-07-11240
Chlorotrimethylsilane Mediated Synthesis of 5-(2-Hydroxybenzoyl)pyrimidines from 3-Formylchromones

Sergey V. Ryabukhin,* Andrey S. Plaskon, Dmitriy M. Volochnyuk, Sergey E. Pipko, and Andrey A. Tolmachev

*Enamine Ltd. 23 A. Matrosova st., 01103 Kyiv, Ukraine


The recyclization of 3-formylchromones with a variety of 1,3-NCN-binucleophiles promoted by chlorotrimethylsilane was investigated. A simple and flexible general procedure for the synthesis of series of 5-(2-hydroxybenzoyl)pyrimidines and their heterofused analogues was proposed. A set of pyrimidines was obtained in high preparative yields.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 599 - 609
Published online: 22nd November, 2007
DOI: 10.3987/COM-07-11244
A Facile Synthesis of 1,3-Dihydroisobenzofurans Using Iodocylization of 2-Vinylbenzyl Alcohols

Kazuhiro Kobayashi,* Kazuaki Shikata, Shuhei Fukamachi, and Hisatoshi Konishi

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


An efficient route for the preparation of 1,3-dihydroisobenzofurans based on the iodine-mediated cyclization of 2-vinylbenzyl alcohols, which can be prepared feasibly by reactions of 2-vinylphenyllithiums with carbonyl compounds, is reported. Substitution reactions of the iodo moiety of the resulting 1-(iodomethyl)-1,3-dihydroisobenzofurans with tributyltin hydride and sodium thiolates are also described.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 611 - 618
Published online: 11th December, 2007
DOI: 10.3987/COM-07-11246
Synthesis and Bioactivity of Novel Bisphosphonate Derivatives

B. Hari Babu, G. Syam Prasad, M. F. Stephen Babu, Pallamreddy Haranath, S. Hemadri Reddy, and C. Naga Raju*

*Department of Chemistry, Sri Venkateswara University, Tirupati-517502, India


Synthesis of novel bis-(2,10-dimethyl-4,8-di-t-butyl-12H-6-oxido-dibenzo[d,g] [1,3,2] dioxaphosphocin -6-yl) 2/3/4-substituted phenyl / heteroaryl-methanes were accomplished by Pudovic reaction. Addition of an equimolar quantities of 2,2’-methylene-bis (6-tert-butyl-4-methyl phenol) 1 and EtOH to PCl3 afforded cyclic condensation product. This on reaction with respective aldehydes followed by treatment with phosphorus (III) monochloride of 1, corresponding bisphosphonate intermediates were formed which on subsequent stirring at reflux temperature rearranged from P(III) to P(V) state.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 619 - 634
Published online: 11th December, 2007
DOI: 10.3987/COM-07-11250
Synthesis of 4’-Thiopurine Nucleosides Using Hypervalent Iodine Compounds

Naozumi Nishizono,* Kayo Soma, Ryosuke Baba, Minoru Machida, and Kazuaki Oda*

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


The reaction of a silylated purine base with thiofuranoid using phenyl iodosyl bis(trifluoroacetate) gave 4’-thio purine nucleosides.

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Paper | Regular issue | Vol 75, No. 3, 2008, pp. 635 - 643
Published online: 14th December, 2007
DOI: 10.3987/COM-07-11251
Synthesis and Characterization of Some Tetracyclic Spermine Derivatives of Cyclotriphosphazene: The First Examples of Dispiransa Derivatives

Gönül Yenilmez Çiftçi,* Esra Tanriverdi, and Yunus Zorlu

*Department of Chemistry, Gebze Institute of Technology, Gebze 41400, Kocaeli, Turkey


The synthesis and characterization is reported of a series of dispiransa cyclophosphazene derivatives based on the known compound N3P3X2[HN(CH2)3N(CH2)4N(CH2)3NH], (2) (where X = Cl), to give a number of new compounds (3a-g) in which X = Ph, PhS, PhNH, PhO, MeO, EtO, CF3CH2O, respectively. Two synthetic routes were utilized: (i) reaction of spermine with the appropriate disubstituted cyclophosphazenes (1) to give compounds (3a-c) and (ii) using the chloro-precursor (2) in nucleophilic substitution reactions with nucleophiles to give compounds (3d-g). The structures of the compounds were determined by elemental analysis, mass spectrometry, 1H and 31P NMR spectrocsopy.

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Note | Regular issue | Vol 75, No. 3, 2008, pp. 645 - 653
Published online: 14th December, 2007
DOI: 10.3987/COM-07-11184
Flavonoidal C-Glycosides from Abutilon pakistanicum

Munawar Hussain, Durey Nayab Zahra, Abdul Malik, Asam Ejaz, Hina Siddiqui, Muhammad Iqbal Choudary, and Zaheer Ahmed*

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


Two new flavonoidal C-glycosides provisionally named as pakistoside A (1) and pakistoside B (2) have been isolated from the aerial parts of Abutilon pakistanicum. Their structures have been assigned through detailed spectral analyses including 2D-NMR techniques. In addition kaempferol, kaempferol-3-O-α-L-rhamnopyranoside and luteolin are isolated for the first time from this plant.

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Note | Regular issue | Vol 75, No. 3, 2008, pp. 655 - 660
Published online: 16th November, 2007
DOI: 10.3987/COM-07-11237
Facile One-Pot Reaction for the Regioselective Syntheses of 2H-[1,2,4]Thiadiazolo[2,3-a]pyrimidine Derivatives

Guohua Liu,* Mei Yao, Yunning Xue, Haibin Fang, and Xiqowei Cao*

*Department of Chemistry, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234, P. R. China


A convenient and rapid method for the preparation of 2H-1,2,4-thiadiazole[2,3-a]pyrimidine derivatives 3a-3e was developed. The investigations of their regioselective syntheses through a comparison of the different substituted groups on the pyrimidine ring using a semi-empirical MO calculation and an X-Ray crystallographic analysis was also discussed.

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Note | Regular issue | Vol 75, No. 3, 2008, pp. 661 - 668
Published online: 7th December, 2007
DOI: 10.3987/COM-07-11242
Three New Furanosesquiterpenoids from Bombax malabaricum and Revised NMR Assignment of Hibiscone C

Xiaohui zhang, Shuwei Zhang, and Lijiang Xuan*

*State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institute for Biological Sciences, Chinese Academy of Science, 555 Zuchongzhi Rd., Zhangjiang Hi-Tech Park, Shanghai, 201203, China


Hibiscone C (1), and three new furanosesquiterpenoids, namely bombaside, bombaxone, and 7β-O-β-glucopyranosyl bombaxone (2-4), were isolated from the roots of Bombax malabaricum. Their structures were characterized by extensive 1D and 2D NMR spectroscopic analyses. The NMR assignment of hibiscone C was revised.

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Note | Regular issue | Vol 75, No. 3, 2008, pp. 669 - 673
Published online: 7th December, 2007
DOI: 10.3987/COM-07-11248
Silica Sulfuric Acid-Activated Poly-1,3,-dichloro-5-methyl-5(4’-vinylphenyl)hydantoin (PDCVH) as an Effective Reagent for Oxidation of 1,3,5-Trisubstituted 2-Pyrazolines Both under Microwave Irradiation and Thermal Condition

Davood Azarifar,* Behrooz Maleki, and Mehrnaz Setayeshnazar

*Faculty of Chemistry, Bu-Ali Sina University, Zip Code 65178, Hamedan, Iran


Oxidation of 1,3,5-trisubstituted 4,5-dihydro-1H-pyrazoles to the corresponding pyrazoles has been achieved by utilizing silica sulfuric acid-activated poly-1,3-dichloro-5-methyl-5(4’-vinylphenyl)hydantoin in EtOH under both microwave irradiation and conventional thermal condition at room temperature with good yields.

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Note | Regular issue | Vol 75, No. 3, 2008, pp. 675 - 681
Published online: 14th December, 2007
DOI: 10.3987/COM-07-11255
A Simple Synthesis of α-Nitro-δ-keto Nitrile

Nagatoshi Nishiwaki,* Tomoko Nogami, and Masahiro Ariga*

*Department of Chemistry, Osaka Kyoiku University, Asahigaoka 4-698-1, Kashiwara, Osaka 582-8582, Japan


α-Nitro-δ-keto nitrile was effectively synthesized in one-pot from pyridinium salt of nitroisoxazolone by ring opening reaction followed by condensation with two molecules of acetone via pyrrolidinium salt of 2,4-di-aci-nitropentanedinitrile. The obtained α-nitro-δ-keto nitrile has a highly acidic hydrogen in addition to multi-functionality. These structural features are considered to be useful for the syntheses of polyfunctionalized compounds.

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16 data found. 1 - 16 listed