Regular Issue

Vol. 43, No. 7, 1996

21 data found. 1 - 21 listed
Communication | Regular issue | Vol 43, No. 7, 1996, pp. 1361 - 1364
Published online:
DOI: 10.3987/COM-96-7415
Variations in the Chemical Shift of the 5-Hydroxyl Proton of 7-O-Prenylated Flavanones

Toshio Fukai and Taro Nomura*

*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan


In 1H nmr examination of 6- or 8-phenylated flavanone 7-methyl and 7-prenyl ethers, the signals of hydrogen-bonded hydroxyl proton appearedin relatively narrow region. Relatively large solvent effect was observedon the signal of 6-prenylflavanone 7-methyl and 7-prenyl ethers.

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Communication | Regular issue | Vol 43, No. 7, 1996, pp. 1365 - 1370
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DOI: 10.3987/COM-96-7446
Short Synthetic Route to 5,6-Dihydroflavopereirine and Flavopereirine

Mauri Lounasmaa,* Pirjo Hanhinen, and Sami Lipponen

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


A short synthetic route to 5,6-dihydroflavopereirine (1) and flavopereirine (2) is described.

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Communication | Regular issue | Vol 43, No. 7, 1996, pp. 1371 - 1374
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DOI: 10.3987/COM-96-7456
Oxidation of Furans with 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone(DDQ)

Shinsei Sayama* and Yutaka Inamura

*Department of Chemistry, Fukushima Medical College, Hikarigaoka, Fukushima, 960-12, Japan


2,5-Disubstituted furans were oxidatively cleaved to 2-butene-1,4-diones with DDQ in CH2Cl2-DMSO. In particular, 3-alkoxy-2,5-diphenylfurans were selectively converted into cis-2-alkoxy-1,4-diphenyl-2-butene-1,4-diones with DDQ in CH2Cl2.

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Communication | Regular issue | Vol 43, No. 7, 1996, pp. 1375 - 1379
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DOI: 10.3987/COM-96-7475
Highly Effective Procedure for Introduction of Amino Group into the 2-Position of Imidazole Ring

Ikuo Kawasaki, Norio Taguchi, Youko Yoneda, Masayuki Yamashita, and Shunsaku Ohta*

*Kyoto Pharmaceutical University, Misasagi, Yamashina, Kyoto 607-8414, Japan


Procedures for the preparation of 2-amino- and 2-arylaminobenzimidazoles were developed, and one of the efficient procedure was applied ot the synthesis of preclathridine A, a marine imidazole alkaloid isolated from a sponge.

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Communication | Regular issue | Vol 43, No. 7, 1996, pp. 1381 - 1384
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DOI: 10.3987/COM-96-7479
Diastereoselective Reduction of Cyclic Imines and β-Enamino Esters

Giang Vo Thanh, Jean-Pierre Célérier, Anne Fleurant, Cyrille Grandjean, Sylvie Rosset, and Gérard Lhommet*

*Laboratoire de Chimie des Hétérocycles URA 408, Université P. et M. Curie, 4, Place Jussieu - case 43 F-75252 Paris Cedex 05, France


The chemical an diastereoselective reduction of cyclic imines and β-enamino esters has been investigated and exploited as an efficient method of synthesis of trans disubstituted pyrrolidines.

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Communication | Regular issue | Vol 43, No. 7, 1996, pp. 1385 - 1390
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DOI: 10.3987/COM-96-7481
Total Synthesis of (+)-7-Deoxypancratistatin and (+)-7-Deoxy-trans-dihydronarciclasine

Noritaka Chida,* Makoto Jitsuoka, Yoshiyuki Yamamoto, Masami Ohtsuka, and Seiichiro Ogawa

*Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Hiyoshi, Kohoku-ku Yokohama 223-8522, Japan


The chiral and stereoselective synthesis of antimitotic phenanthridone alkaloids, (+)-7-deoxypancratistatin (1) and (+)-7-deoxy-trans-dihydronarciclasine (2) is described. Both natural products were synthsized from common compound (4), which had been prepared from D-glucose and employed for the synthesis of lycoricidine (3).

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1391 - 1402
Published online:
DOI: 10.3987/COM-95-7368
A New Entry to Pyrano[3,2-f]indolizines via the Regioselective Formation of an Indolizidin-7-one Enamine

Olivier Pollet, Guy Cordonnier, Cherif Bengourina, Clarisse Randria, and Henri Sliwa*

*Laboratoire de Chimie Organique et Environnement, Université des Sciences et Technologies de Lille, Bat. C4 -2eme Etage 59655 Villeneuve d' Ascq Cedex, France


From indolizidin-7-one (1), the preparation of several (pyrrolidine, piperidine and morpholine) enamines was described. The isolation of one of them (morpholine) as a pure regioisomer allowed the synthesis of pyrano[3,2-f]indolizines for which only a few examples were known.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1403 - 1414
Published online:
DOI: 10.3987/COM-96-7400
Preparation of N-Alkylnorpavines via Competitive N-Dealkylation of Quaternary Pavines

Shoei-Sheng Lee *and Kuo-Tung Tung

*School of Pharmacy, National Taiwan University, 1, Jen-Ai Road, Section 1, Taipei 10018, Taiwan, R.O.C.


N-Alkyl quaternary pavine salts were converted into N-alkyl teriary pavines by refluxing ethanolamine, via a competitive N-dealkylation mechanism. The following N-dealkylation order was observed: benzyl>allyl>Me>Et>nPr>nBu. Further study indicated that N-alkyl- and N-acylpavine could be obtained from N-methyl tertiary pavines in a one-pot reaction (acid anhydride/allyl bromide or alkyl halide, reflux). This finding provides an alternative method for preparing N-alkyl tertiary pavines.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1415 - 1421
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DOI: 10.3987/COM-96-7414
Studies in Cell Suspension Cultures of Cassia didymobotrya. Part VI. The Biotransformation of Chalcones to Aurones and Auronols

Bruno Botta,* Giuliano Delle Monache,* Maria Cristina De Rosa, Rosalba Scurria, Alberto Vitali, Vittorio Vinciguerra, Pilar Menendez, and Domenico Misiti

*Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, 00185 Roma, Italy


Cell-free extracts derived from tissue cultures of Cassia didymobotrya, which previously had been reported to convert 4-hydroxychalcones to flavones and biflavanones, catalyze the biotransformation of 2-hydroxychalcones to aurones and auronols. The aurone was shown to be the direct precursor of auronol.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1423 - 1437
Published online:
DOI: 10.3987/COM-96-7436
Improved Syntheses of 5,10,15,20-Tetrakisaryl- and Tetrakisalkylporphyrins

Robert A. W. Johnstone,* M. Luisa P. G. Nunes, Mariette M. Pereira, Antonio M. d'A. Rocha Gonsalves, and Arménio C. Serra

*Department of Chemistry, University of Liverpool, Liverpool, L69 3BX, U.K.


Three significant modifications to existing methods for the preparation of the important 5,10,15,20-tetrakisarylporphyrins have improved isolated ylides, simplified work-up and made large-scale synthesis feasible. Two tetrakisalkylporphyrins were also producted. A two-stage approach using hydrogen peroxide in acetic acid as second stage oxidant gave good yields but for ease of isolation and convenience in working on a large scale, the one-pot approach is preferred. No one method appears to be suitable for all such tetrakisarylporphyrins and, for best yields, the method of preparation needs to be chosen carefully. Application of statiscal optimisation techniques (factorial two design and simplex operation) led to considerably enhanced yields for the one-pot method. For one of th two-stage modifications, significant amounts of chlorins were observed, sometimes of such magnitude as to make it suitable as a method for their preparation.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1439 - 1446
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DOI: 10.3987/COM-96-7444
A Short Total Synthesis of Palonosetron Using Catalytic Hydrogenation

Bruce A. Kowalczyk

*Chemical Development, Syntex Research, Palo Alto, California 94304, U.S.A.


The 5-HT3 receptro antagonists (1) and (2) (palonosetron) were synthesized by anefficient new route. The critical hydrogenation of imide (4) was carried out with either Pd/C catalyst or PtO2 catalyst.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1447 - 1457
Published online:
DOI: 10.3987/COM-96-7453
Synthesis of 3-Unsubstituted-1-aminopyrroles

Orazio A. Attanasi, Lucia De Crescentini, Raffaello Giorgi, Ada Perrone, and Stefania Santeusanio

*Istituto di Chimica Organica, Facolta di Scienze, Università di Urbino, Piazza della Repubblica 13, I-61029 Urbino, Italy


3-Unsubstituted 1-aminopyrroles have been obtained by mild reaction of some α-halohydrazones with β-dicarbonyl compounds in bais medium. The reaction takes place by formation of conjugated azoalkene intermediate and, in turn, of Michael-type adduct, which cyclizes into title compounds by subsequent treatment in methanol under reflux, or in tetrahydrofuran with sulfuric acid at room temperature.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1459 - 1464
Published online:
DOI: 10.3987/COM-96-7455
Convenient Preparation of 3-Methoxycarbonylpyridazines by Palladium Catalyzed Alkoxycarbonylation of Pyridazinetriflates

Markus Rohr, Dominique Toussaint, Saïd Chayer, Andre Mann,* Jean Suffert , and Camille-Georges Wermuth

*Laboratoire de Pharmacochimie Moleculaire, Centre de Neurochimie du CNRS, 5, rue Blaise Pascal, 67084 Strasbourg-Cedex, France


The methoxycarbonylation of several pyridazine-trifluoromethanesulphonates with CO and MeOH is catalyzed by Pd(OAc)2 and 1,1’-bis(diphenylphosphino)ferrocene. This method constitutes a mild and efficient homologation of pyridazinones.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1465 - 1470
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DOI: 10.3987/COM-96-7461
Synthesis of Imidazole N-Oxides in Solvent-free Conditions

Jesús Alcázar, Mikael Begtrup, and Antonio de la Hoz*

*Facultad de Química, Universidad de Castilla-La Mancha, Campus Universitario, 13071 Ciudad Real, Spain


Cyclization of 1,2-diimines with oximes was performed under solvent-free conditions using silica gel and aluminium oxide as supports and catalysts. The reaction proceeded under milder reaction conditions to give imidazole N-oxides. The N-oxides were obtained in higher yields by easier work-up procedure than in the usual reactions performed in solution.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1471 - 1475
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DOI: 10.3987/COM-96-7467
Expedient Preparations of 2-Trifluoromethylindole and Its N-Methyl Derivative

Kevin E. Henegar and David A. Hunt*

*Chemical Discovery Department, Agricultural Producsts Research Division Attn: Library, American Cyanamid Company, P. O. Box 400, Clarksville Raod Princeton, NJ 08543-0400, U.S.A.


Procedures have been developed which provide direct regiocontrolled syntheses of 2-trifluoromethylindole and 1-methyl-2-tifluoromethylindole from readily available starting materials in moderate yields.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1477 - 1482
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DOI: 10.3987/COM-96-7468
Melianolide, a New Limonoid of Biogenetic Interest, from Chinese Melia azedarach L.

Ruo Chun Huang, Yuji Minami, Fumio Yagi, Yumiko Nakamura, Noboru Nakayama, Kenjiro Tadera, and Munehiro Nakatani*

*Department of Chemistry, Faculty of Science, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065, Japan


Melianolide, a new limonoid of biogenetic interest, was isolated along with salannal and four known ring C-seco limonoids, nimbolinin B, salannin, deacetylsalannin and nimbolidin B, from the root bark of Chinese Melia azadarach L. (Meliaceae). The structure is proposed on the basis of special data.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1483 - 1496
Published online:
DOI: 10.3987/COM-96-7474
Synthesis of Acetamido(indol-3-yl)propanol Derivatives

Martha S. Morales-Ríos, L. Gerardo Zepeda, Oscar R. Suárez-Castillo, and Pedro Joseph-Nathan*

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


A series of acetamido(indol-3-yl)propanol derivatives (5-7) has been synthesized using a variety of reductive reactions performed on the corresponding O-methyl oximes of an indol-3-yl ester and of several indol-3-yl alcohol derivatives. The O-methyl oximes were prepared in good yields by acylation of the corresponding zinc salt of indole, followed by O-methyl oximation.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1497 - 1512
Published online:
DOI: 10.3987/COM-96-7493
An Attempted Total Synthesis of Lysergic Acid via an Alkene/N-Sulfonylimine Cyclization

Janet L. Ralbovsky, Paul M. Scola, Eiichi Sugino, Carolina Burgos-Garcia, Steven M. Weinreb,* and Masood Parvez

*Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, U.S.A.


Lewis acid-promoted cyclization of the N-tosylimine derived from aldehyde alkene (18) affords an interesting rearranged seven-membered ring tricycle (21) rather than the expected intermediate containing the lysergic acid skeleton.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1513 - 1519
Published online:
DOI: 10.3987/COM-96-7494
Novel Violet Pigment, Nostocine A, an Extracellular Metabolite from Cyanobacterium Nostoc spongiaeforme

Kazumasa Hirata, Hirofumi Nakagami, Jun Takashina, Taifo Mahmud, Motomasa Kobayashi, Yasuko In, Toshimasa Ishida, and Kazuhisa Miyamoto*

*Faculty of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Toyonaka, Osaka 560-0043, Japan


A freshwater cyanobacterium, Nostoc spobgiaeforme TISTR 8169, produced and excreted a novel violet pigment, nostocine A (1), which had board-spectrum of growth inhibitory activity. The chemical structure of 1 was determined as 6-methyl-1,3,6,7,8-pentaazabicyclo[4.3.0]nonan-1,3,5(7)-trien-9-one on the bases of physicochemical evidence and an X-ray crystallographic analysis.

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Paper | Regular issue | Vol 43, No. 7, 1996, pp. 1521 - 1527
Published online:
DOI: 10.3987/COM-96-7497
Occurrence of Xanthonolignoids in Guttifereous Plants

Munekazu Iinuma*, Hideki Tosa, Toshiyuki Tanaka, Tetsuro Ito, Sigetomo Yonemori, Veliah Chelladurai, Mohammad Aquil, Yoshikazu Takahashi, and Hiroshi Naganawa

*Departmeny of Pharmacognosy, Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan


Further investigation of the chemical constituents of the Guttifereous plants (Calophyllum inophyllum, C. austroindicym and Harungana madagascariensis) led to isolate two new xanthonolidnoids, named calophyllumins A and B, in addition to two known xanthonolignoids (cadensin C and 6-hydroxycadensis F) and four flavonoids (calophyllic acid, quercetin, quercetin 3-O-rhamnoside and amentoflavone). The structures of these compounds were established by the asids of spectroscopic analysis including 2D nmr technique.

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Review | Regular issue | Vol 43, No. 7, 1996, pp. 1529 - 1558
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DOI: 10.3987/REV-95-477
Photochemical Reactions Involving Pyrroles – Part II

Maurizio D'Auria

*Dipartimento di Chimica, Università della Basilicata, Via N. Sauro 85 85100 Potenza, Italy


The photochemical behavior of pyrrole derivatives was described showing that the photochemical methodologies in this field can offer some interesting synthetic procedures. Furthermore, the use of pyrrole derivatives in photochemical reactions has been used in order to synthesized some interesting products.

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21 data found. 1 - 21 listed