Regular Issue

Vol. 68, No. 7, 2006

18 data found. 1 - 18 listed
Communication | Regular issue | Vol 68, No. 7, 2006, pp. 1319 - 1324
Published online: 30th May, 2006
DOI: 10.3987/COM-06-10702
Reductive Formation of 1,5-Benzothiazepines

Albert Lévai,* Gábor Tóth,* Tímea Gondos, József Jekö, and Dinkarao I. Brahmbhatt

*Department of Organic Chemistry, University of Debrecen, Egyetem tér 1, H-4010 Debrecen, P.O.Box 20, Hungary


An unprecedented formation of a new type of 1,5-benzothiazepines with exocyclic double bond at position 4 has been achieved by the reaction of 3-aryl-1-(3-coumarinyl)propen-1-ones with 2-aminothiophenol.

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Communication | Regular issue | Vol 68, No. 7, 2006, pp. 1325 - 1328
Published online: 30th May, 2006
DOI: 10.3987/COM-06-10727
Synthesis of N1-Unsubstituted 5-Alkynylcytosine and Derivatives Thereof

Robert H. E. Hudson* and Andrew K. Dambenieks

*Department of Chemistry, University of Western Ontario, London, Ontario, N6A5B7, Canada


The first examples of 5-alkynylcytosines (3) lacking other ring substitution have been synthesized directly from Sonogashira coupling of 5-iodocytsoine (1) with terminal alkynes. Alternatively, 7H-pyrrolo[2,3-d]pyrimidin-2(H)-ones (4), via domino cross-coupling and cyclization reactions were prepared from N4-benzoyl-5-iodocytosine (2). Both the 5-phenylethynylcytosines and bicyclic derivatives show substituent-dependent fluorescence.

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Communication | Regular issue | Vol 68, No. 7, 2006, pp. 1329 - 1334
Published online: 16th May, 2006
DOI: 10.3987/COM-06-10765
Enantioselective Microbial Hydrolysis of Disubstituted Cyclic Carbonates

Masaki Nogawa, Megumi Shimojo, Kazutsugu Matsumoto,* Hiromichi Ohta, and Minoru Hatanaka

*Deaprtment of Chemistry, Meisei University, Hodokubo 2-1-1, Hino, Tokyo 191-8506, Japan


Pseudomonas diminuta (FU0090), a bacterium, efficiently catalyzes the hydrolysis of five-membered cyclic carbonates bearing two substituents, which are methyl and another groups to give the corresponding optically active 1,2-diols.

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Paper | Regular issue | Vol 68, No. 7, 2006, pp. 1335 - 1348
Published online: 30th May, 2006
DOI: 10.3987/COM-05-10590
Hypervalent Organoantimony Compound 12-Aryltetrahydrodibenz[c,f][1,5]azastibocine: New Transmetallating Agent for Palladium-Catalyzed Arylation of Organic Halides

Naoki Kakusawa and Jyoji Kurita*

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


Palladium-catalyzed cross-coupling reaction of 12-aryltetrahydrodibenz[c,f][1,5]azastibocines with acyl chlorides and aryl iodides was investigated. Although this type of arylation is hardly possible with non-activated triarylstibanes, the intramolecular N---Sb non-bonding interaction in the 1,5-azastibocine facilitates transmetallation of the aryl group in a Stille-type catalytic cycle, and a wide range of acyl chlorides and aryl iodides were arylated with the azastibocine in the presence of 5 mol% of PdCl2(PPh3)2. Acceleration of the coupling reaction was also demonstrated under microwave irradiation.

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Paper | Regular issue | Vol 68, No. 7, 2006, pp. 1349 - 1357
Published online: 12th May, 2006
DOI: 10.3987/COM-06-10715
Synthesis and Basic Optical Properties of New π-Conjugated Thiophene-Pyridine Co-oligomers

Hiroki Fukumoto, Akira Kumagai, Yoshiki Fujiwara, Hideomi Koinuma, and Takakazu Yamamoto

*Research Laboratory of Resources Utilization, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan


Two series of π-conjugated thiophene-pyridine co-oligomers, Py-Th-(Th)m-Th-Py (Py = pyridine unit; Th = thiophene unit; 4a: m = 0; 5a: m = 1; 6a: m = 2) and Th-Py-(Th)m-Py-Th (4b: m = 0; 5b: m = 1; 6b: m = 2), have been prepared by palladium- or nickel-promoted C-C coupling reaction in high yields. The π-π* absorption peak of Py-Th-(Th)m-Th-Py (390-440 nm) is observed at a longer wavelength than that of Th-Py-(Th)m-Py-Th (345-410 nm) with the same m number. These UV-vis data are considered to reflect a charge transfer (CT) interaction between the thiophene (donor) and pyridine (acceptor) units. 4a-6a, 5b, and 6b show photoluminescence in a range of 430-540 nm and give quantum yields (φ) of 20-40%. 4b affords a high quantum yield of φ = 71%. A linear correlation holds between the π-π* transition energy and the inverse of the number of the aromatic units [1/(m+4)] for the 4a-6a and 4b-6b series.

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Paper | Regular issue | Vol 68, No. 7, 2006, pp. 1359 - 1370
Published online: 30th May, 2006
DOI: 10.3987/COM-06-10726
An Efficient and Convenient Method for Synthesis of 1-Substituted Imidazoles

Chun Min Lin, Fung Fuh Wong,* Jiann-Jyh Huang, and Mou-Yung Yeh

*Sustainable Environment Research Center, National Cheng Kung University, No. 500, Sec. 3, An-ming Rod., Tainan City, 709, Taiwan, R.O.C.


A convenient method for the synthesis 1-substituted imidazoles was developed by the reaction of α-bromoketone with lithium imidazolide. The reaction gave the desired products in improved yields without the formation of 1,3-disubstituted imidazolium salts. Treatment of bromoacetaldehyde ethylene acetal, 2-(bromomethyl)tetrahydro-2H-pyran, and N-(bromomethyl)phthalimide with lithium imidazolide also gave the corresponding 1-substituted imidazole in good to excellent yields. Direct reaction of α-bromoketone with imidazole as control experiment afforded undesired 1,3-disubstituted imidazolium salts with the desired mono-substituted products.

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Paper | Regular issue | Vol 68, No. 7, 2006, pp. 1371 - 1379
Published online: 23rd May, 2006
DOI: 10.3987/COM-06-10731
Novel Azolinium/Rhodium System Catalyzed Addition of Arylboronic Acids to Aldehydes

Ismail Özdemir,* Murat Yigit, Engin Çetinkaya, and Bekir Çetinkaya

*Department of Chemistry, Faculty of Science and Arts, Inönü University, 44280 Malatya, Turkey


There novel 1,3-dialkylperhydrobenzimidazolinium (2a-c) and two 1,3-dialkylimidazolinium salts (4a,b) as NHC precursors were synthesized from N,N’-dialkyl-1,2-cyclohexanediamine dihydrochloride and 1,2-dialkylpropanediamine dihydrochloride. The in situ prepared three component system [RhCl(COD)]2 / imidazolinium salts (2, 4) and KOBut catalyses the addition of phenylboronic acid to sterically hindered aldehydes affording the corresponding arylated secondary alcohols in good yields.

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Paper | Regular issue | Vol 68, No. 7, 2006, pp. 1381 - 1392
Published online: 16th May, 2006
DOI: 10.3987/COM-06-10743
Solid-State Photocycloaddition of 6,6’-Dimethyl-4,4’-polymethylenedioxy-di-2-pyrones to Benzophenone

Weidong Wang, Tetsuro Shimo,* Teruo Shinmyozu, Tetsuo Iwanaga, and Kenichi Somekawa

*Department of Applied Chemistry, Faculty of Engineering, Kagoshima University, Korimoto 1-21-40, Kagoshima 890-0065, Japan


Solid-state photocycloaddition reactions of 6,6’-dimethyl-4,4’-polymethylenedioxy-di-2-pyrones (1a-e) with benzophenone (2a) gave the corresponding oxetane derivatives (3a-e; 1:2 adducts) with high site- and regioselectivities across the C5-C6 and C5’-C6’ double bonds in 1 via the triplet excited state of benzophenone. Since the yields of oxetanes between 1b,d (methylene chain length n=3,5) having odd methylene chains and 2a in the solid state were higher than those of 1a,c,e (n=2,4,6) having even methylene chains, it was suggested that the former mixed crystal formation is easier than the latter case. The oxetane formation proceeded more effectively in the solid state than in solution.

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Paper | Regular issue | Vol 68, No. 7, 2006, pp. 1393 - 1400
Published online: 12th May, 2006
DOI: 10.3987/COM-06-10748
Synthesis of 4-(Dimethylamino)pyridinium-substituted Pyrazine, Pyridazine, 1,3,5-Triazine, Purine, and Imidazole

Andreas Schmidt* and Thorsten Mordhorst

*Institute of Organic Chemistry, Clausthal University of Technology, Leibnizstrasse 6, D-38678 Clausthal-Zellerfeld, Germany


Substitution reactions of 2,3-dichloropyrazine, 3,6-dichloropyridazine, 2,4,6-trichloro-1,3,5-triazine, 2,6-dichloropurine, and N-tosyl-2,4,5-tribromoimidazole with 4-(dimethylamino)pyridine to monocationic, dicationic, and tricationic hetarenium salts are described.

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Paper | Regular issue | Vol 68, No. 7, 2006, pp. 1401 - 1407
Published online: 1st June, 2006
DOI: 10.3987/COM-06-10763
The First Synthesis of (-)-Plakolide A

Keizo Matsuo,* Masaru Kanayama, and Keiji Nishiwaki

*Faculty of Pharmaceutical Sciences, Kinki University, 3-4-1, Kowakae, Higashi-Osaka 577-8502, Japan


(-)-Plakolide A, an α-exomethylene-γ-butyrolactone isolated from the marine sponge Plakortis sp., was synthesized starting from (R)-lactic acid by applying the chiral self-reproduction procedure.

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Note | Regular issue | Vol 68, No. 7, 2006, pp. 1409 - 1419
Published online: 26th May, 2006
DOI: 10.3987/COM-06-10732
Regio- and Exo-π-Facial Selective 1,3-Dipolar Cycloaddition of α-(3-Pyridyl)-N-phenylnitrone to Norbornadiene: Activation of a π-Bond of Norbornadiene and Control of Regiochemistry of Nitrone Cycloaddition by Nitrone Addition to the Other Double Bond

Gurpinder Singh, Munusamy Elango, Venkatesan Subramaniam, and Mohan Paul Singh Ishar*

*Department of Pharmaceutical Sciences, Guru Nanak Dev University, Amritsar 143005, Punjab, India


Thermal cycloaddition of α-(3-pyridyl)-N-phenylnitrone to a π-bond in norbornadiene not only activates the other double bond towards 1,3-dipolar cycloaddition, it also regulates the regiochemistry of addition leading to regio- and exo-π-facial selective formation of novel 2:1 cycloadducts. A DFT analysis in terms of the global and local reactivity indices affords a rationalization of the obtained results.

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Note | Regular issue | Vol 68, No. 7, 2006, pp. 1421 - 1428
Published online: 12th May, 2006
DOI: 10.3987/COM-06-10747
Enzyme Inhibition Studies of Oxindole Alkaloids from Isatis costata

Itrat Fatima, Ijaz Ahmad, Sarfraz A. Nawaz, Abdul Malik,* Nighat Afza, Ghosia Luttfullah, and M. Iqbal Choudhary

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


Costinones A (1) and B (2), the new oxindole alkaloids have been isolated from Isatis costata along with indirubin (3). Their structures have been assigned on the basis of spaectroscopic data. Both the compounds inhibited lipoxygenase and butyrylcholinesterase enzymes non-competitively in concentration-dependent fashion with promising inhibitory potentials.

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Note | Regular issue | Vol 68, No. 7, 2006, pp. 1429 - 1442
Published online: 23rd May, 2006
DOI: 10.3987/COM-06-10750
Synthesis of Tetrahydrofurfurylamines Related to Muscarine

Roberto Fernández de la Pradilla,* Pilar Manzano, Alma Viso, Javier Fernández, and Antonio Gómez

*Institute of Organic Chemictry, C. S. I. C., Juan de la Cierva, 3, 28006 Madrid, Spain


A methodology that involves mesylation of readily available tetrahydrofuryl diols and subsequent displacement with selected amines to afford novel muscarine analogs has been outlined. Displacement of the primary mesylate takes place smoothly, while displacement of the secondary mesylate occurs in low yield. The use of triflates as an alternative has been sketched.

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Note | Regular issue | Vol 68, No. 7, 2006, pp. 1443 - 1449
Published online: 12th May, 2006
DOI: 10.3987/COM-06-10753
Polyphosphoric Acid-Induced Construction of Quinazolinone Skeleton from 1-(3,4-Dimethoxyphenyl)-3-phenylurea and Carboxylic Acids

Iliyan Ivanov,* Stoyanka Nikolova, Ekaterina Kochovska, and Stela Statkova-Abeghe

*Department of Organic Chemistry, University of Plovdiv, 24, Tsar Assen Str. 4000 Plovdiv, Bulgaria


A general synthesis of a series 4-substituted 3,4-dihydro-2(1H)-quinazolinones (7) included polyphosphoric acid (PPA)-induced cyclization with carboxylic acids. Modification at the 4-position of the quinazolinone skeleton was best achieved by variation of carboxylic acids. Starting 1-(3,4-dimethoxyphenyl)-3-phenylurea (3) was prepared from the phenylisocyanate and 3,4-dimethoxyaniline.

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Note | Regular issue | Vol 68, No. 7, 2006, pp. 1451 - 1454
Published online: 12th May, 2006
DOI: 10.3987/COM-06-10754
Asymmetric Synthesis of (-)-Verrucosapyrone A by Biocatalyst and Determination of Its Absolute Configuration

Takuzo Komiyama, Yutaka Takaguchi, and Sadao Tsuboi*

*Department of Environmental Chemistry and Materials, Faculty of Environmental Science and Technology, Okayama University, 2-1-1 Tsushima-naka, Okayama 700-8530, Japan


An asymmetric synthesis of (-)-verrucosapyrone A was achieved by the use of biocatalyst. Absolute configuration of verrucosapyrone A was also investigated.

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Note | Regular issue | Vol 68, No. 7, 2006, pp. 1455 - 1458
Published online: 16th May, 2006
DOI: 10.3987/COM-06-10755
A New Butenolide-Type Fungal Pigment from the Mushroom Pulveroboletus ravenelii

Ling Zhang, Fei Wang, Ze-Jun Dong, Wolfgang Steglich, and Ji-Kai Liu*

*State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Heilongtan, Kunming 650204, Yunnan, China


A new butenolide-type fungal pigment, pulverolide (1) was isolated from the fresh fruiting bodies of Pulveroboletus ravenelii, together with a related known compound pulveraven A (2). The structure of pulverolide (1) was elucidated on the basis of spectroscopic studies including extensive 2D NMR experiments.

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Note | Regular issue | Vol 68, No. 7, 2006, pp. 1459 - 1466
Published online: 1st June, 2006
DOI: 10.3987/COM-06-10759
Structural Characterization of Isomeric Methyl 2-(2-Oxo-3-indolyl)acetate and Methyl 1-(2-Oxo-4-quinolyl)formate

Ernesto Rivera-Becerril, Nury Pérez-Hernández, Pedro Joseph-Nathan, and Martha S. Morales-Ríos*

*Departmento de Química del Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Apartado 14-740, México, D.F., 07000, Mexico


Crystalline and amorphous forms of methyl 2-(2-oxo-3-indolyl)acetate (1) were obtained showing significant differences in their melting points. The X-ray structure for the trigonal polymorph is reported. In addition, oxindole (1) was easily acid-catalyzed ring enlarged to give the structural isomer quinolone (2) for which the crystal structure was also determined. These results resolve several chemical inquiries related to the structural characterization of 1 and 2.

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Review | Regular issue | Vol 68, No. 7, 2006, pp. 1467 - 1500
Published online: 16th May, 2006
DOI: 10.3987/REV-06-606
Supramolecular Species Bearing Quaternary Azaaromatic Moieties

Wanda Sliwa* and Barbara Bachowska

*Institute of Chemistry and Environmental Protection, Jan Dlugosz University of Czestochowa, al. Armii Krajowej 13/15, 42-201 Czestochowa, Poland


In the paper at first rotaxanes are presented; these species are divided into three classes, i.e. those containing electron donor, electron acceptor and cyclodextrin molecules as rings. In following parts examples of catenanes, pretzelanes and molecular clips are described.

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18 data found. 1 - 18 listed