Regular Issue

Vol. 41, No. 12, 1995

21 data found. 1 - 21 listed
Communication | Regular issue | Vol 41, No. 12, 1995, pp.2647-2650
Published online:
DOI: 10.3987/COM-95-7254
Synthesis, Property, and X-Ray Crystal Structure of New Dibenzophosphaselenocines

Hisashi Fujihara,* Tohru Nishioka, Hisatomo Mima, and Naomichi Furukawa*

*Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki 305, Japan

Abstract

New phosphorus-selenium heterocycles, dibenzophosphaselenocines (1 and 2), have been prepared. The structure of the dibenzophosphaselenocines was determined by multinuclear nmr spectroscopy and X-ray diffraction analysis.

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Communication | Regular issue | Vol 41, No. 12, 1995, pp.2651-2656
Published online:
DOI: 10.3987/COM-95-7255
4',1'a-Methanocarbocyclic Adenosine Analogues as Potential Inhibitors of S-Adenosylhomocysteine Hydrolase

Lak S. Jeong, Victor E. Marquez,* Chong-Shen Yuan, and Ronald T. Borchardt

*Laboratory of Medicinal Chemistry, Developmental Therapeutics Program, Division of Cancer Treatment, National Cancer Institute, NIH, Bethesda, Maryland 20892, U.S.A.

Abstract

Cyclopropane-fused carbocyclic adenosine (4) and its 5’-carboxaldehyde analogue (5) were synthesized as potential inhibitors of S-adenosylhomocysteine hydrolase. The key bicyclo[3.1.0]hexane alcohol (8) was obtained from the optically pure cyclopentenone synthon (6), and attachment of the purine base was performed in a single step from the methylsulfonate ester of 8 (compound (9)). Both target compounds behaved as weak inhibitors of the hydrolase.

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Communication | Regular issue | Vol 41, No. 12, 1995, pp.2657-2660
Published online:
DOI: 10.3987/COM-95-7275
Reaction of 1-Pyridiniothiobenzoylaminides with Dimethyl Acetylenedicarboxylate

Akikazu Kakehi, * Suketaka Ito, Fumihito Ishida, and Yoshinori Tominaga

*Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, Wakasato, Nagano 380, Japan

Abstract

The reactions of 1-pyridiniothiobenzoylaminides with dimethyl acetylenedicarboxylate in chloroform at 50-60 °C provided dimethyl 5-thia-2,3-diazatricyclo[4.3.2.02,7]undeca-3,8,10-triene-6,11-dicarboxylate derivatives in moderate yields. The structures of these products were assumed by their spectral and analytical data and determined finally by the X-ray analysis of one compound.

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Communication | Regular issue | Vol 41, No. 12, 1995, pp.2661-2664
Published online:
DOI: 10.3987/COM-95-7276
Acetylations of (±)-Agelasimine-A and (±)-Agelasimine-B: A Racemic Synthesis of Purino-Diterpene Derived from Antimicrobial Metabolites of Agelas mauritiana

Masashi Ohba*, Nobuo Kawase, and Tozo Fujii

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

Abstract

The reaction of (±)-agelasimine-A [(±)-3a] with acetic anhydride in pyridine yielded the imidazole derivative [(±)-5a], which was found to correspond to "diacetylagelasimine-A". A similar acetylation of (±)-agelasimine-B [(±)-4a] provided (±)-7a and (±)-2a. On treatment with boiling 50% aqueous EtOH, (±)-7a gave (±)-2a and the dihydrohypoxanthine derivative [(±)-8a]. It is suggested that purino-diterpene (2a), isolated from the acetylated mixture of the crude extract of the sponge Agelas mauritiana, might have originated from agelasimine-B (4a) through N6-acetylagelasimine-B (7a).

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2665-2682
Published online:
DOI: 10.3987/COM-95-7029
Efficient and Regioselective Photocyclization Reactions of N-[(ω-Trimethylsilylmethoxy)polyoxalkyl]phthalimides to Azacrown Ethers

Ung Chan Yoon*, Sun Wha Oh, and Chan Woo Lee

*Department of Chemistry, College of Natural Sciences, Pusan National University, Pusan 609-735, Korea

Abstract

Single electron transfer induced photocyclization reactions of N-[(ω-trimethylsilylmethoxy)polyoxalkyl]phthalimides have been explored. Photocyclizations occur in methanol in modest to high yield to produce cyclized products in which phthalimide carbonyl carbon is bonded to the ω-carbon of side chain in place of the trimethylsilyl group. The efficient, chemoselective, and regioselective cyclization reactions represent synthetically useful processes for construction of azacrown ethers of various sizes.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2683-2690
Published online:
DOI: 10.3987/COM-95-7122
Substrate Specificity of Vinorine Hydroxylase, a Novel Membrane-bound Key Enzyme of Rauwolfia Indole Alkaloid Biosynthesis

Heike Falkenhagen, Leo Polz, Hiromitsu Takayama, Mariko Kitajima, Shin-ichiro Sakai, Norio Aimi, and Joachim Stöckigt*

*Institute of Pharmacy, Johannes Gutenberg-Universität Mainz, Staudinger Weg 5, 55099 Mainz, Germany

Abstract

The novel membrane bound enzyme vinorine hydroxylase exhibits an extraordinary high substrate specificity which points to its key function in the biosynthesis of monoterpenoid indole alkaloids of the ajmaline type in cell suspension cultures of the Indian medicinal plant Rauwolfia serpentina.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2691-2699
Published online:
DOI: 10.3987/COM-95-7123
Photosynthesis of Heteropolycyclic Diquinolones Twofold Photodehydrohalogenation Reaction of Benzo[1,2-b:4,5-b']dithiophene- and Dithieno[3,2-b:2',3'-d]thiophenedicarboxanilides

Miro Malesevic, Grace Karminski-Zamola*, Miroslav Bajic, and David W. Boykin

*Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, 41000 Zagreb, Croatia

Abstract

Heteropolycyclic diquinolones; benzo[1,2-b:4,5-b']dithieno[2',3'-c':2",3"-c"]-5,13-N,N'-dimethyldiquinoline-6,14-dione (9) and dithieno[3,2-b:2',3'-d]thienyl[2",3"-c:2",3"-c']-5,10-N,N-dimethyldiquinoline-6,9-dione (17) are prepared by twofold photochemical dehydrohalogenation reaction of corresponding benzodithiophene- and dithienothiophenedicarboxanilides; 3,7-dichloro-N,N'-dimethylbenzo[1,2-b:4,5-b']dithiophene-2,6-dicarboxanilide (8) and 3,5-dichloro-N,N'-dimethyldithieno[3,2-b:2',3'-d]thiophene-2,6-dicarboxanilde (16). The products of onefold photochemical dehydrohalogenation reaction, anilidoquinolones; 9-chloro-10-N'-methylanilidobenzo[1,2-b:4,5-b']dithieno[2,3-c']-5-N-methylquinolin-6-one (10) and 10-chloro-9-N'-methylanilidodithieno[3,2-b:2',3'-d]thienyl[2",3"-c']-5-N-methylquinolin-6-one (18) were also isolated to prove the mechanism of the reaction.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2701-2711
Published online:
DOI: 10.3987/COM-95-7137
A Controlled Stepwise Oxidation of Ethyl 2-Oxothiazolidine-4-carboxylate to the Corresponding 2-Hydroxythiazole

Gloria Serra, David González, and Eduardo Manta*

*Cátedra de Química Farmacéutica, Facultad de Química, Universidad de la República, Av. General Flores 2124. C. C. 1157, 11800 Montevideo, Uruguay

Abstract

Methyl 2-hydroxythiazole-4-carboxylate was obtained via a controlled stepwise oxidative procedure from the corresponding 2-oxothiazolidine. A series of intermediates have been isolated and characterized, supporting the ionic and radical mechanisms already proposed in the literature.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2713-2728
Published online:
DOI: 10.3987/COM-95-7141
Substituted Benzimidazoles. Part 1. Synthesis and Properties of Some 2-Aryl-5-fluoro-6-(4-methyl-1-piperazinyl)-1H-benzimidazoles

Mustafa M. El-Abadelah*, Salim S. Sabri, Musa H. Abu Zarga, and Raid J. Abdel-Jalil

*Chemistry Department , University of Jordan, Amman, Jordan

Abstract

2-Aryl-5-fluoro-6-(4-methyl-1-piperazinyl)benzimidazoles (8a-k) were synthesized for bioassay via interaction of 4-fluoro-5-(4-methyl-1-piperazinyl)-1,2-diaminobenzene (6) with the appropriate aldehyde. The intermediate Schiff bases (7a-k) were isolated and converted, thermally in nitrobenzene, to the respective heterocycles (8a-k). However, none of the tested model compounds (8c-e) showed any significant in vitro activity against Pseudomonas aeruginosa, Staphylococcus aureus, Aspergillus parasiticus and Candida albicans at concentration < 100 μg/ml.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2729-2736
Published online:
DOI: 10.3987/COM-95-7187
Stereoselective Reduction of the Double Bond in Δ5-3-Oxo-4-azasteroids

Jacek W. Morzycki,* Agnieszka Z. Wilczewska, Ewa Zochowska, and Zenon Lotowski

*Institute of Chemistry, University of Warsaw, Bialystok Branch, Pilsudskiego 11/4, 15-443 Bialystok, Poland

Abstract

The stereoselective borohydride/H+ reduction of the C(5)-C(6) double bond in Δ5-3-oxo-4-azasteroids has been studied. The intermediate acylimine is preferentially attacked by borohydride from the α side. The optimization with respect to the type of borohydride, solvent, catalyst and temperature has been carried out.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2737-2744
Published online:
DOI: 10.3987/COM-95-7196
Synthesis of 2-Substituted Isothiazolo[5,4-b]pyridin-3(2H)-one 1,1-Dioxides

Victor Martinez-Merino,* Maria J. Gil, Jose M. Zabalza, and Alberto Gonzalez

*Departamento de Química, Universidad Pública de Navarra, 31006 Pamplona, Spain

Abstract

The isothiazole[5,4-b]pyridin-3(2H)-one 1,1-dioxides (3a-g) were prepared from the corresponding isothiazolo[5,4-b]pyridin-3(2H)-ones (1a-g) by means of an oxidation with oxone® (KHSO5) and sodium hypochlorite (NaOCl) in two steps. The influence of the substituents (R), in position 2 of this system, on the oxidation process was studied. While the oxidation of 1a-g with 3-chloroperoxybenzoic acid gave yields of 3a-g depending greatly on the nature of R, the combined KHSO5/NaOCl method gave good yields of 3a-g in all of the cases studied.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2745-2760
Published online:
DOI: 10.3987/COM-95-7211
Synthesis of 17- and 21-Membered Macrocycles Incorporating the Chiral 1,1'-Binaphthyl Backbone and Nitrogen, Oxygen, and Phosphorus Donor Atoms

Petra Wimmer, Gerd Klintschar, and Michael Widhalm*

*Institut für Organische Chemie, Universität Wien, 1090 Wien, Austria

Abstract

A 17-membered diaza-diphospha- and a 21-membered diaza-dioxadiphospha-macrocycle (6) and (12), respectively, including the inherent chiral binaphthyl moiety were synthesized. Titanium(IV) mediated cyclization of 1,1’-binaphthyl-2,2’-dicarbaldehyde (4) with 1,3-bis[(2-aminophenyl)phenylphosphino]propane (8) and subsequent reduction afforded 6a-c as a mixture of three diastereomers in 14% overall yield. Ligand (12) was obtained from the nickel amido complex of 8 and 2,2’-bis[2-(4-toluene)sulfonyloxyethoxy]-1,1’-binaphthyl (10a) by a template synthesis in the presence of Cs2CO3 in 63% yield. X-Ray structure determinations of cationic Ni(II) complexes of 6a and 12 were performed.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2761-2768
Published online:
DOI: 10.3987/COM-95-7213
Ficusins A and B, Two New Cyclic-Monoterpene-substituted Isoflavones from Ficus septica Barm. F.

Miwa Aida, Yoshio Hano, and Taro Nomura*

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

Abstract

Two new cyclic-monoterpene-substituted isoflavones, ficusins A (1) and B (2) were isolated from the Indonesian moraceous plant, Ficus septica Barm. F. The structures of ficusins A and B were shown to be 1 and 2, respectively, on the basis of spectroscopic data.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2769-2776
Published online:
DOI: 10.3987/COM-95-7221
Synthesis of N-Substituted 3-Aminomethyl-2,3-dihydrofuro[2,3-c]pyridines, Potent Serotoninergic Ligands

Benoît Joseph, Abdelhakim Benarab, and Gérald Guillaumet*

*Laboratoire de Chimie Bioorganique et Analytique associé au CNRS, Université d'Orléans, BP 6759, 45067 Orléans Cedex 2, France

Abstract

Regioselective lithiation of 2-chloro-3-oxiranylmethoxypyridine, followed by intramolecular epoxide ring-opening reaction provided (7-chloro-2,3-dihydrofuro[2,3-c]pyridin-3-yl)methanol (1). Multistep synthesis from 1 gave a variety of N-substituted 3-aminomethyl-2,3-dihydrofuro[2,3-c]pyridines as potent serotoninergic ligands.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2777-2784
Published online:
DOI: 10.3987/COM-95-7233
Reaction of 4-Amino-1,2,4-triazolium Salts with Polarized Olefins

Yoshiro Matsuda*, Yasusige Chiyomaru, Kazuki Furuno, and Takanobu Nishiyori

*School of Pharmaceutical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852, Japan

Abstract

The reaction of 4-amino-1,2,4-triazolium salts (5a,b) with polarized olefins (3a,b, 4a) in the presence of K2CO3 in EtOH or DMSO directly yielded the back-donated 1,6-cyclization products, mesomeric betaines (6a-c, 7a,b) via N-vinylimino ylides, while the reaction of the salts (5a,b) with polarized olefins (4b,c) gave the 1,5-dipolar cyclization products, pyrazoles (10a, b) and [1,2,4]triazolo[4,3-b]pyrazole (11).

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2785-2793
Published online:
DOI: 10.3987/COM-95-7235
New Diels-Alder Reactions of Oxy-functionalized 3-Vinylindoles with Carbodienophiles

Ulf Pindur* and Martina Rogge

*Department of Chemistry and Pharmacy, Institute of Pharmacy, University of Mainz, Saarstrasse 21, D-55122 Mainz, Germany

Abstract

Some new Diels-Alder reactions of oxy-functionalized 3-vinylindoles (1, 2) with carbodienophiles are described. In most cases, functionalized carbazoles (4 - 6, 10 and 11) were formed regio- and/or endo-selectively. The product spectrum is characterized by [4+2] cycloadditions, elimination and ene reaction.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2795-2798
Published online:
DOI: 10.3987/COM-95-7240
Trichilinins B and C, Two New Limonoids from Melia toosendan

Jian-Bo Zhou, Hiroaki Okamura, Tetsuo Iwagawa, Yumiko Nakamura, Noboru Nakayama, Kenjiro Tadera, and Munehiro Nakatani*

*Department of Chemistry, Faculty of Science, Kagoshima University, Korimoto, Kagoshima 890, Japan

Abstract

Two new limonoids, trichilinins B and C, were isolated along with four nimbolidins and salannin from the root bark of Melia toosendan.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2799-2809
Published online:
DOI: 10.3987/COM-95-7245
Synthesis of 6-Substituted 2-Phenyloxazolo[4,5-b]pyridines

Marie-Claude Viaud, Patricia Jamoneau, Laurence Savelon, and Gérald Guillaumet*

*Laboratoire de Chimie Bioorganique et Analytique associé au CNRS, Université d'Orléans, BP 6759, 45067 ORLEANS Cedex 2, France

Abstract

The synthesis of 2-phenyloxazolo[4,5-b]pyridines substituted in position 6 by alkyl, aryl, benzyl, formyl, acetyl, benzoyl and nitrile group is described.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2811-2821
Published online:
DOI: 10.3987/COM-95-7247
Sorocenols C-F, Four New Isoprenylated Phenols from the Root Bark of Sorocea bonplandii Baillon

Yoshio Hano, Juntaro Yamanaka, Yasunori Momose, and Taro Nomura*

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

Abstract

From the root bark of Sorocea bonplandii Baillon (Moraceae), collected in Paraguay, four new isoprenylated phenols, sorocenols C (1), D (2), E (3), and E (4) were isolated along with four known isoprenylated phenols, mulberrofuran K (5), kuwanon J (6), chalcomoracin (7), and kuwanol E (8). The structures of sorocenols C -F were shown to be 1 - 4, respectively. These compounds are regarded as variations of Diels-Alder type adducts between chalcone derivatives and dehydroisoprenylated phenols.

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Paper | Regular issue | Vol 41, No. 12, 1995, pp.2823-2826
Published online:
DOI: 10.3987/COM-95-7256
Facile Preparation of (3S)-1,3-Dimethyl-3-cyanomethyl-5-ethoxyoxindole from Julian's Nitrile Enriched in the (3S)-Enantiomer

Xue-Feng Pei* and Arnold Brossi

*Laboratory of Bioorganic Chemistry, NIDDK, NIH, Bldg. 8, Rm. 1A-20, Bethesda, MD 20892, U.S.A.

Abstract

(3S)-1,3-Dimethyl-3-cyanomethyl-5-ethoxyoxindole (4a) was prepared in high optical purity from a 4a enriched enantiomeric mixture obtained by asymmetric 3-cyanomethylation of oxindole (11) by removal of the racemate a single recrystallization.

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Review | Regular issue | Vol 41, No. 12, 1995, pp.2827-2873
Published online:
DOI: 10.3987/REV-95-469
Chemistry of Persistent Free Bi- and Polyradicals

Mohab-Eddine Brik

*Laboratoire de Chimie Structurale Organique, ICMO URA CNRS 1384, Bat 410, Université de Paris-Sud, 91405 Orsay Cedex, France

Abstract

The aim of this paper is to provide an overview of important developments in the chemistry and the use of persistent free bi- and polyradicals to study chemical and biological model systems by electron paramagnetic resonance (epr) or as materials for physical purposes. The paper also discusses the different ways used to synthesize these molecules by structure modifications of carboxylic and heterocyclic nitroxides as well as their diamagnetic precursors. The review tries to sum up our knowledge of these strong paramagnetic species with the aim of drawing the reader’s attention to their application in recent fields of physics, chemistry, biochemistry, biology and and medical radiology including magnetic resonance imaging (mri) and more recently electron spin resonance imaging (esri).

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21 data found. 1 - 21 listed