Regular Issue

Vol. 38, No. 9, 1994

18 data found. 1 - 18 listed
Communication | Regular issue | Vol 38, No. 9, 1994, pp. 1957 - 1960
Published online:
DOI: 10.3987/COM-94-6769
Density Functional Calculations on Heterocyclic Compounds. Part 2. On the Protonation of 4,5-Dichloro-2-methyl-3(2H)-pyridazinone

Péter Mátyus,* Kaoru Fuji, Kiyoshi Tanaka,* Janos Rohonczy, Richárd Hargitai, and Pál Sohár*

*Department of General and Inorganic Chemistry, Loránd Eötvös University, H-1518 Budapest 112, P.O.Box 38, Hungary


Studies on protonation of the title compound by DF and ab initio quantum chemical methods as well as 13C-nmr relaxation measurements revealed that O-protonation took place.

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Communication | Regular issue | Vol 38, No. 9, 1994, pp. 1961 - 1964
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DOI: 10.3987/COM-94-6803
A New Procedure for Construction of 2,6-trans-Disubstituted Piperidines Using Osmium-catalyzed Asymmetric Dihydroxylation: Application to the Synthesis of (+)-Epidihydropinidine and (+)-Solenopsin A1

Hiroki Takahata,* Kumiko Inose, Naomi Araya, and Takefumi Momose*

*Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama, Toyama 930-0194, Japan


An aymmetric synthesis of (+)-epidihydropinidine (1) and (+)-solenopsin A (2) has been achieved by starting with the Sharpless asymmetric dihydroxylation of the α-amino acid-derived N-alkenylurethanes (3) followed by subsequent aminocyclization.

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Communication | Regular issue | Vol 38, No. 9, 1994, pp. 1965 - 1970
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DOI: 10.3987/COM-94-6804
Structure and Stereochemistry of Divarine: Another New Bisindole Alkaloid from Strychnos divaricans Ducke

Rabindranath Mukherjee,* Bhupesh C. Das, Paul A. Keifer, and James N. Shoolery

*Laboratório de Tecnologia Farmacêutica, Universidade Federal da Paraiba, 58051-970 João Pessoa, PB, Brazil


The complete stereostructure of divarine, a new bisindole alkaloid from Strychnos divaricans Ducke., has been determined mainly by the use of one- and two-dimensional nmr techniques.

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Communication | Regular issue | Vol 38, No. 9, 1994, pp. 1971 - 1974
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DOI: 10.3987/COM-94-6816
Synthesis of Sulfur-containing Heterocycles by Thermolysis of α-Alkylthio-N-aziridinylimines

Sunggak Kim* and Chang Mook Cho

*Department of Chemistrym Korea Advanced Institute of Science and Technology, 373-1, Kusung-Dong, Yusung-Gu, Taejon, 305-701, Korea


Thermolysis of α-alkylthio substituted N-aziridinylimines in refluxing toluene gave various structurally different sulfur-containing heterocycles in high yields.

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Communication | Regular issue | Vol 38, No. 9, 1994, pp. 1975 - 1978
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DOI: 10.3987/COM-94-6835
Synthesis of Strained 8-Membered Heterocyclic Allenes by [3,3] Sigmatropic Rearrangement and Their Reactivities

Shinya Harusawa, Hideki Moriyama, Hirofumi Ohishi, Ryuji Yoneda, and Takushi Kurihara*

*Faculty of Pharmaceutical Science, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan


A new type of 8-membered heterocyclic allenes were synthesized by the [3,3] sigmatropic ring expansion of 6-membered cyclic thionocarbonates. The MNDO optimized structure indicated the allenyl moiety in cyclic allene (3) is bent and strained. Reactivities of the heterocyclic allenes were also examined.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 1979 - 2003
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DOI: 10.3987/COM-91-5783
Direct Polynitroaliphatic Alcohol Addition to Alkenes. 3. Synthesis, Structure and Intramolecular Electron Impact Stability of the Uniquely Structured 2,4-Dimethyl-7,7-dinitro-1,3,5-trioxacyclooctane

Raymond R. McGuire, J. Lloyd Pflug, Margaret H. Rakowsky, Scott A. Shackelford,* and Alan A. Shaffer

*Materials Chemistry Division, F.J. Seiler research Laboratory (AFMC), 2354 Vandenberg Drive, Suite 2A35, USAF Academy, Colorado 80840-6272, U.S.A.


Mercury(I) sulfate catalyzed addition between the difunctional 2,2-dinitropropane-1,3-diol (ADIOL) and the divinyl ether (DVE) diene reactants produces either an apparent acyclic acetal oligomer, or the unexpected eight-membered 2,4-dimethyl-7,7-dinitro-1,3,5-trioxacyclooctane. Proton nmr and deuterium labeling of this heterocyclic compound reveals it is comprised of both meso and dl diastereomers caused from its two chiral carbon atoms. Because this heterocycle incorporates both gem-2,2-dinitroalkyl and cyclic trioxane acetal structural fragments into one hybrid saturated ring structure, a novel intramolecular electron impact stability comparison can be made between the structural features representative of the normally unrelated geminal polynitroalkane and cyclic polyoxane compound classes which determine the fragmentation pathway of the subject heterocycle.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2005 - 2008
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DOI: 10.3987/COM-93-6650
Tamynine - A New Alkaloid from Murraya paniculata

Mohammad Ataullah Khan,* Shaikh Sirajuddin Nizami, Tehmina Qamar, Tahir Rasheed, Muhammad Najmul Islam Khan, and S. Wasif Azeem

*Department of Chemistry, University of Karachi, Karachi-75270, Pakistan


A new alkaloid tamynine has been isolated from Murraya paniculata. Its structure has been assigned as 1 on the basis of chemical and spectral studies.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2009 - 2015
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DOI: 10.3987/COM-94-6761
Condensed as-Triazines: Synthesis of Imidazo[4,5-e]-as-triazine 1-Oxides (6-Azapurine 6-Oxides) as Guanine and Hypoxanthine Analogues

Dau-Chang Wei, Long-Chih Hwang, and Cherng-Chyi Tzeng*

*School of Chemistry, Kaohsiung Medical University, 100 Shin Chuen 1st Rd., Kaohsiung 80708, Taiwan, R.O.C.


Imidazo[4,5-e]-as-triazine 1-oxides (6-azapurine 6-oxides), structurally related to guanine and hypoxanthine, have been prepared. Reaction of 5,6-diamino-3-methylsulfonyl-as-triazine 1-oxide (1) with hydrazine afforded 5,6-diamino-3-hydrazino-as-triazine 1-oxide (2) which was then oxidized with mercuric oxide to give 5,6-diamino-as-triazine 1-oxide (3). The 3-methylsulfonyl group of 1 was also replaced with liquid ammonia and methanolic ammonia respectively to give 3-amino (5) and 3-methoxy (6) derivatives. as-Triazine N-oxides were then cyclized with triethyl orthoformate (TEOF) to afford the title compounds.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2017 - 2022
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DOI: 10.3987/COM-94-6770
1,2,3-Triazolo[5,1-b]thiazoles. Part 3. The Reaction between a Triazolothiazolium Ylide and Acetylenic Dipolarophiles

Belén Abarca,* Rafael Ballesteros, María J. Del Rincón-Guaita, and Gurnos Jones*

*Departamento de Química Orgánica, Facultad de Farmacia, Universidad de Valencia, Avda. Vicente Andres Estelles, 46100, Burjasot (Valencia), Spain


The reaction between 2-methoxycarbonylmethyl-3-methyl-1,2,3-triazolo[5,1-b]thiazolium ylide (5) and methyl propiolate gives the dienes (7) and (8). Existence of this type of diene was postulated in previous papers but they were not isolated. However the reaction of 5 with dimethyl acetylendicarboxylate gives a simple pyrrolo[2,1-b]thiazole system (13).

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2023 - 2026
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DOI: 10.3987/COM-94-6781
Synthesis of Sydnoquinoxalines and Bis(sydnonylphenyl)urea

Wing Lai Chan,* James A. Waite, Yuan Hua Lin, and Yan Shan Szeto

*Department of Applied Biology and Chemical Technology, Hong Kong Polytechnic, Hung Hom, Kowloon, Hong Kong


Sydno[3,4-a]quinoxalin-4-one (2) and -4-thione (3) were prepared directly from 3-(o-aminophenyl)sydnone (1) with phenyl isocyanate, 1,1‘-carbonyl diimidiazol (CoIm2) and phenyl isothiocyanate respectively in good yield. N,N‘-Bis[o-(3-sydnonyl)phenyl]urea (4) was also obtained under slightly different conditions between 1 and CoIm2.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2027 - 2044
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DOI: 10.3987/COM-94-6785
Preparation and Conformational Study of Z-Isositsirikine Model Compounds and Their cis-Nb-Oxides. Determination of the C-16 Configuration

Pirjo Hanhinen, Tomi Nurminen, Reija Jokela,* and Mauri Lounasmaa*

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


Preparation of Z-isositsirikine derivatives (5 - 12) from the allylic alcohols (21) and (22) by the orthoester Claisen rearrangement and their oxidation to the corresponding cis-Nb-oxides (13 - 20) are described. Nmr methods were applied to determine the configuration at C-16 of Z-isositsirikine derivatives and their cis-Nb-oxides. A general, nmr based conformational study of compounds (5 -20) is presented.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2045 - 2050
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DOI: 10.3987/COM-94-6788
Synthesis of Crown Ethers Containing a Sulfide Group Inside the Ring and High Ag+ Selectivity in Solvent Extraction

Tatsuya Nabeshima,* Hiroyuki Furusawa, and Yumihiko Yano

*Faculty of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu 376-8515, Japan


Crown ethers bearing a sulfide, a sulfoxide, or a sulfone group inside the ring have been prepared and the sulfide derivatives exhibit a significantly high Ag+ selectivity in solvent extraction.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2051 - 2064
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DOI: 10.3987/COM-94-6790
Novel Redox Derivatives of Tryptophan

Emil Pop,* Marcus E. Brewster, Katalin Prókai-TÁtrai, and Nicholas Bodor

*Pharmos Corporation, 2 Innovation Drive, Alachua, FL 32615, U.S.A.


The design, synthesis and study of some physicochemical properties of several potential brain targeting chemical delivery systems (CDS) of D,L-tryptophan (Trp) are described. CDS‘s are based on a 1,4-dihydropyridine ⇔ pyridinium salt-type redox system. The dihydropyridine moiety was chemically attached to the amino group of Trp by either substituted amino or substituted carbamate linkages. While the amide bond-containing derivatives are known to be rather stable toward in vivo hydrolysis, the parent Trp can be readily released from the substituted carbamate-type combinations. Lipophilicity and chemical oxidation studies performed on the new derivatives indicated that some of the new CDSs possess the properties required for an improved and specific brain delivery of Trp.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2065 - 2072
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DOI: 10.3987/COM-94-6797
A Ready Entry to Substituted Derivatives of Pyrido[3",2":4‘,5‘]thieno[2‘,3‘:5,6]pyrido[2,3-d]pyrimidines, a New Tetraheterocyclic Ring System

Carlos Peinador, Ma. Carmen Veiga, Vicente Ojea, and José Ma. Quintela*

*Departamento de Química Fundamental Industrial, Facultad de Ciencias, Universidad de La Coruña, Campus de A Zapateria, s/n, E-15071, La Coruña, Spain


Several 4-substituted pyrido[3",2":4‘,5‘]thieno[2‘,3‘:5,6]pyrido]2,3-d]pyrimidines (4) and (5) were prepared by reaction of an appropriate substituted thieno[2,3-b:4,5-b‘]dipyridine (2) and (dichloromethylene)dimethylammonium chloride.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2073 - 2079
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DOI: 10.3987/COM-94-6805
Synthesis of Novel 4-Arylamino-2-dialkylaminoquinazolines under High Pressure

Akihiro Oishi,* Masahiko Yasumoto,* Midori Goto, Tohru Tsuchiya, Isao Shibuya, and Yoichi Taguchi

*National Institute of Materials and Chemical Research, 1-1, Higashi, Tsukuba, Ibaraki 305, Japan


Novel 4-arylamino-2-dialkylaminoquinazolines (salt) were obtained in good yields by reaction of dialkylcyanamides with 4-substituted phenyl isothiocyanates at 800 MPa. The molecular structure of 6-chloro-4-(4‘-chlorophenylamino)-2-dimethylaminoquinazoline 2"-chlorobenzoate (3e) was determined by X-ray crystallographic analysis.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2081 - 2089
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DOI: 10.3987/COM-94-6811
Pyridazines, 71. A Novel Type of 1,2-Diazine Æ 1,2-Diazole Ring Contraction

Gottfried Heinisch, Barbara Matuszczak,* and Kurt Mereiter

*Institute of Pharmaceutical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria


Reaction of the 3,6-dichloro-4-pyridazinecarboxamide derivative (2) with sodium hydride in dimethylformamide does not afford a pyridazino[3,4-b][1,5]benzodiazepine system (3) but results in a ring transformation to give the quinoxalinyl-substituted pyrazole derivative (4). The structure of this unexpected reaction product could be elucidated by means of a crystal structure determination; a mechanistic interpretation of this novel type of a pyridazine → pyrazole ring contraction is proposed.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2091 - 2097
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DOI: 10.3987/COM-94-6818
An Efficient Synthesis of Di- and Trimethoxy-4-quinolones

Jun Toda, Takako Fuse, Etsuko Kishikawa, Naoko Ando, Rumi Negishi, Yoshie Horiguchi, and Takehiro Sano*

*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan


An excellent method of preparation of N-aryl-enamino esters (4) was achieved by developing N-N exchange of an N-methyl-enamino ester (6) with di- and trimethoxyanilines (3). Thermolysis of 4 in xylene gave di- and trimethoxy-4-quinolones (7) in excellent yields.

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Paper | Regular issue | Vol 38, No. 9, 1994, pp. 2099 - 2114
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DOI: 10.3987/COM-94-6829
On the Reaction of Substituted Phenols and 3-Methylbut-2-enoic Acid. A Comparative Study

Péter Sebok, József Jeko, Tibor Tímár,* and Joseph Cs. Jaszberenyi

*Department of Research, Alkaloida Chemical Co. Ltd., H-4440 Tiszavasvári, POB 1, Hungary


A systematic and comparative study of the reaction of a series of substituted phenols and 3-methylbut-2-enoic acid in zinc chloride/phosphorus oxychloride and aluminum chloride/phosphorus oxychloride reveals that the formation of phenolic esters and 2,2-dimethyl-4-chromanones is strongly influenced by the substituents, their position on the aromatic ring of the starting phenols. Based on our study, a mixed Friedel-Crafts and Fries rearrangement mechanism is in operation in these reactions.

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18 data found. 1 - 18 listed