Regular Issue

Vol. 41, No. 5, 1995

22 data found. 1 - 22 listed
Communication | Regular issue | Vol 41, No. 5, 1995, pp.877-881
Published online:
DOI: 10.3987/COM-94-7018
Synthesis of a Flavin Receptor for Regulation of Ion Recognition by Assembling Components Necessary for a Binding Site

Tatsuya Nabeshima*, Norio Tamura, Tomokazu Kawazu, Kazue Sugawara, and Yumihiko Yano

*Department of Chemistry, Gunma University, Kiryu, Gunma 376, Japan

Abstract

A flavin receptor with two 2,6-diacylaminopyridine moieties as the binding sites was synthesized. Upon complexation between the host and flavins bearing a polyether chain, the complex exhibits higher extractability toward K+ than the host or the guest alone.

PDF (137KB)
Communication | Regular issue | Vol 41, No. 5, 1995, pp.883-888
Published online:
DOI: 10.3987/COM-95-7026
A Possible Explanation for Preferential Stabilization of the Substituent Axial Conformation in Alkoxy- or Siloxy-substituted Six-membered Cyclic Compounds by the σ → σ* Orbital Overlap: Remarkable Effect of Electron-withdrawing Groups

Yoshimitsu Nagao* and Michimasa Goto

*Faculty of Pharmaceutical Sciences, The University of Tokushima, Sho-machi, Tokushima 770, Japan

Abstract

The substituent axial conformation in alkoxy- or siloxy-substituted six-membered cyclic compounds must be stabilized by the existence of an electronwithdrawing group or a double bond in their molecules, which can be rationalized in terms of the σ(C-H)→σ*(C-OR) or π(C=C)→σ*(C-OR) orbital overlap concept. The basicity of the oxygen atom of alkoxy and siloxy substituent groups may effect the relative stability of the substituent axial conformer.

PDF (154KB)
Communication | Regular issue | Vol 41, No. 5, 1995, pp.889-892
Published online:
DOI: 10.3987/COM-95-7027
Preparation and Multi-Nuclear NMR Study of New Benzodichalcogenaphospholes

Satoshi Ogawa, Mitsugu Saito, Michiko Ogasawara, and Ryu Sato*

*Department of Applied Chemistry and Molecular Science, Faculty of Engineering, Iwate University, Morioka 020, Japan

Abstract

Benzene fused 5-membered dichalcogenaheterocycles containing sulfur, selenium, and phosphorus, 2-phenyl-1,3,2-benzodichalcogenaphospholes (4), were newly prepared by the reactions of corresponding 2,2-dimethyl-1,3,2-benzodichalcogenastannoles (3) with dichlorophenylphosphine in excellent yields. The structure of these new 5-membered heterocycles containing tin, phosphorus, sulfur, and selenium was characterized by multi-nuclear nmr experiments.

PDF (158KB)
Communication | Regular issue | Vol 41, No. 5, 1995, pp.893-896
Published online:
DOI: 10.3987/COM-95-7052
Efficient Synthesis and Biological Properties of New Benzopentathiepins

Ryu Sato,* Tetsuya Ohyama, and Satoshi Ogawa

*Department of Applied Chemistry and Molecular Science, Faculty of Engineering, Iwate University, Morioka 020, Japan

Abstract

New 6,7-dimethoxybenzopentathiepin and 6-(2-aminoethyl)benzopentathiepin, which are partial structures of varacin, were synthesized from 1,2-dimethoxybenzene and 1,2-benzenedithiol respectively.

PDF (133KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.897-909
Published online:
DOI: 10.3987/COM-94-6677
1-Acyl-2-alkyl-3,4-epoxy-1,2,3,4-tetrahydroquinolines — Synthesis and Reactions with N-Nucleophiles

Martin Kratzel* and Romana Hiessböck

*Institut für Pharmazeutische Chemie der Universität Wien, Währinger Strasse 10, A-1090 Wien, Austria

Abstract

Epoxide opening of the title compounds (6) with primary or secondary amines using lithium perchlorate as catalyst gave 1,2,3,4-tetrahydroquinolines with stereochemically well defined substitution pattern in the piperidine moiety (7,8). By-products (9,10), formed by acyl migration, were observed.

PDF (412KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.911-919
Published online:
DOI: 10.3987/COM-94-6810
Regioselective Thermal Cyclization of 3-Substituted Arylenaminoimine Hydrochlorides, a Convenient Method for the Synthesis of Functionalized Polycyclic Quinoline Derivatives

Gandhi K. Kar, Arun C. Karmakar, Anindita Makur (nee' Chatterjee), and Jayanta K. Ray*

*Department of Chemistry, Indian Institute of Technology, Kharagpur 721302, W. B., India

Abstract

3-Substituted arylenaminoimine hydrochlorides on heating produced exclusively one regioisomer for electron donating groups at 3 position whereas two regioisomers for electron withdrawing/weakly electron donating groups present at the 3 positions.

PDF (199KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.921-930
Published online:
DOI: 10.3987/COM-94-6944
Conversion of Dihydro-1,4-oxathiin-3-carboxamide to the Isomeric Dihydro-1,4-oxathiin-2-carboxamide

Hoh-Gyu Hahn,* Kee-Hyuk Chang, and Wha Suk Lee

*Organic Chemistry Laboratory, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, 130-650, Seoul, Korea

Abstract

The preparation of isomeric dihydro-1,4-oxathiin (3) from the dihydro-1,4-oxathiin (1) via dichloro-1,4-oxathiane (4) is described. Chlorination of 1 followed by treatment of the resulting dichloride (4) with aqueous acetone gave dihydroxy-1,4-oxathiin (5). The solvolysis to produce intermediate chlorohydrin (11) was favored relative to elimination reaction to give exomethylene compound (8). Dehydration of 5 followed by reduction afforded α-hydroxy-1,3-oxathiolane (2) which is a key compound to prepare the isomeric dihydro-1,4-oxathiin (3). The reason for more facile displacement of chlorine at C-2 in comparison with that at C-3 in 4 was also discussed.

PDF (259KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.931-936
Published online:
DOI: 10.3987/COM-94-6964
Synthesis of 17-Azacholesterol

Jacek W. Morzycki* and Zenon Lotowski

*Institute of Chemistry, University of Warsaw, Bialystock Branch, Al. Pilsudskiego 11/4, 15 443, Poland

Abstract

The synthesis of 17-azacholesterol from the N-(3-hydroxy-1-methylpropyl)-17-aza lactam is described. The starting alcohol was oxidized to aldehyde which was treated with isobutylmagnesium bromide. The secondary alcohol obtained was oxidized to ketone. Both ketone and lactam carbonyl groups were consecutively reduced to CH2.

PDF (185KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.937-945
Published online:
DOI: 10.3987/COM-94-6981
Synthesis and Antiviral Evaluation of Furopyrimidine Diones Cyclic and Acyclic, Nucleoside Analogues

Jacques Renault, Fabrice Jourdan, Daniel Ladurée*, and Max Robba

*Centre d'Etudes et de Recherche sur le Médicament de Normandie, U. F. R. des Sciences Pharmaceutiques, 1 rue Vaubénard, 14032 Caen, France

Abstract

Following Vorbrüggen and Niedballa’s method1, we have carried out the synthesis of new cyclic and acyclic nucleoside analogues, whose aglycone was the furopyrimidinedione (3). Among the various compounds that we obtained was the β-D-ribonucleoside (8) which gave us access to the β-D-arabinonucleoside (11) whose synthesis by Vorbüggen and Niedballa’s method1 had remained unsuccessful. All the new compounds were tested against human immunodeficiency virus 1 (HIV-1). None of these compounds showed significant activity.

PDF (298KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.947-958
Published online:
DOI: 10.3987/COM-94-6987
(Diethylamino)sulfur Trifluoride (DAST) as a Useful Reagent for the Preparation of 2-Oxazolines from 1,2-Amido Alcohols

Pierre Lafargue, Pierre Guenot, and Jean-Paul Lellouche*

*CEA, CE-Saclay, Départment de Biologie Cellulaire et Moléculaire, Service des Molécules Marquées, Bt 547, F-91191 Gif-sur-Yvette Cedex, France

Abstract

Acyclic 1,2-amido alcohols (6) react efficiently with a slight excess of (diethylamino)sulfur trifluoride (DAST) to afford the corresponding 2-oxazolines (10) in good yields ranging between 57-95%. Even at the low temperature of -78°C, a rapid (<1 h) and stereoselective amide cyclization is observed without formation of acylaziridine by-products. The scope of this cyclization is discussed.

PDF (338KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.959-972
Published online:
DOI: 10.3987/COM-94-7000
Studies on m-Cyclophane Formation from the Photolysis of Chloroacetamide Derivatives

Robert Rezaie, John B. Bremner*, Gregory K Blanch, Brian W Skelton, and Allan H White

*Department of Chemistry, University of Wollongong, Wollongong, 2522, NSW, Australia

Abstract

The synthesis of 12-hydroxy-2-oxa-6-azabicyclo[7.3.1]trideca-1(13),9,11-trien-5-one (4) is described. Two routes to (4) based on the photolysis of N-[2-(3,4-dimethoxyphenyl)ethyl]chloroacetamide (2b) and N-[2-(4-t-butyldimethylsiloxy-3-methoxyphenyl)ethyl]chloroacetamide (2c) followed by O-demethylation or O-desilylation, were developed. Extension of the work has given the new m-cyclophane ester derivative (9), whose structure has been confirmed by X-ray crystallography.

PDF (396KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.973-982
Published online:
DOI: 10.3987/COM-94-7009
A Convenient Approach to the N-Substituted Amino Dienes, N-Benzyl-5-ethenyl-3,4-dihydropyridin-2-one and N-Cbz-5-Ethenyl-1,2,3,4-tetrahydropyridine

Chiara Bigogno, Bruno Danieli, Giordano Lesma, and Daniele Passarella*

*Dipartimento di Chimica Organica e Industriale, Università degli Studi di Milano, Centro CNR di Studio per le Sostanze Organiche Naturali, Via Venezian 21, 20133 Milano, Italy

Abstract

A synthesis of N-substituted amino dienes (1a) and (1b) is described according to two different approaches. 1a is obtained through condensation of methyl 4-formyl-6-selenophenylhexanoate (4) with benzylamine followed by oxidation and elimination; 1b is formed by a Pd-catalyzed cross-coupling reaction utilizing vinyltributyltin. The preparation of 4 is also described.

PDF (268KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.983-994
Published online:
DOI: 10.3987/COM-94-7016
Synthesis of (2R, 3R, 4R, 5R)-3,4-Dihydroxy-2,5-dihydroxymethylpyrrolidine and (-)-Anisomycin Derivative from (S)-Pyroglutamic Acid Derivative

Nobuo Ikota*

*National Institute of Radiological Sciences, 9-1, Anagawa-4-chome, Inage-ku, Chiba 263, Japan

Abstract

Double asymmetric dihydroxylation of (E)-α,β-unsaturated ester (2) with a catalytic amount of potassium osmate and chiral ligand gave dihydroxy compounds (3a and 4a) selectively. Polyhydroxylated pyrrolidines (10 and 14) were synthesized from corresponding methoxymethy ether (3c) and tert-butyldimethylsilyl ether (4d), respectively.

PDF (446KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.995-1000
Published online:
DOI: 10.3987/COM-95-7033
Preparation of 17-Deoxy-E-isositsirikine cis-Nb-Oxides and Their Use as Model Compounds

Mauri Lounasmaa,* Pirjo Hanhinen, and Reija Jokela

*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, FIN-02150 Espoo, Finland

Abstract

Preparation of (16S*)- and (16R*)-17-deoxy-E-isositsirikine cis-Nb-oxides (5) and (6) is described. Comparison of their 1H-nmr data with those given for E-isositsirikine cis-Nb-oxides (7) and (8) from the South American tree Aspidosperma marcgravianum suggested that the C-16 configurations presented for the naturally occurring compounds have to be interchanged. 13C-Nmr data of compounds (5) and (6) are furnished.

PDF (127KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.1001-1011
Published online:
DOI: 10.3987/COM-95-7035
Synthesis of Substituted 1,8-Naphthyridine Derivatives

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

*Departamento de Química Fundamental e Industrial, Facultad de Ciencias, Universidad de La Coruña, Campus de A Zapateira, E-15071 La Coruña, Spain

Abstract

A variety of substituted 1,8-napthyridines were synthesized from 2-alkoxy-6-amino-3-cyano-5-formyl-4-phenylpyridine (1) by Friedländer condensation with aldehydes, aliphatic,cyclic or aromatic ketones and other active methylene compounds. Reactions of 1 with other compounds, were also studied.

PDF (331KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.1013-1022
Published online:
DOI: 10.3987/COM-95-7037
Cyclization of 2-Dicyanomethylene-1,2-dihydropyridine-3-carbonitriles with Hydrogen Halides: A Re-examination on the Regioselectivity

Pedro Victory, Núria Busquets, José I. Borrell,* Jordi Teixidó, Blanca Serra, Josep Lluís Matallana, Hans Junek, and Heinz Sterk

*Departament de Química Orgànica, CETS Institut Químic de Sarrià, Universitat Ramon Llull, E-08017 Barcelona, Spain

Abstract

The cyclization of the title compounds (5a-c) with HCl and HBr has been re-examined. In all cases 5-amino-7-halo-substituted 1,6-naphthyridines (11a-c and 12a-c) were formed independently of the thermal level and the hydrogen halide employed. The structures of 11a-c and 12a-c were unequivocally established by reaction with hydrazine which afforded the corresponding pyrazolo[3,4-h][1,6]naphthyridines (14a-c). The structure of the methoxy derivatives (15a,c and 16a,c) was assigned by two-dimensional nmr studies.

PDF (304KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.1023-1033
Published online:
DOI: 10.3987/COM-95-7038
Preparation and Stereochemistry of 1,4,8,11-Tetraazaperhydropyrene Derivatives from N,N'-Bis(3-aminopropyl)ethylenediamine

Tadashi Okawara,* Hisashi Takaishi, Yoshinari Okamoto, Tetsuo Yamasaki, and Mitsuru Furukawa

*Faculty of Pharmaceutical Sciences, Kumamoto University, Oe-hon-machi, Kumamoto 862, Japan

Abstract

The reaction of N,N’-bis(3-aminopropyl)ethylenediamine (1) with glyoxal (2) in the presence of benzotriazole (3) afforded dibenzotriazoyltetraazaperhydropyrene (4), which was converted to polyazapolycycles (6), (13), (15), (16), and (19). The stereochemistry is discussed.

PDF (285KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.1035-1043
Published online:
DOI: 10.3987/COM-95-7040
Sorocenols A and B, Two New Isoprenylated Phenols from the Root Bark of Sorocea bonplandii Baillon

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

*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, two new isoprenylated phenols, sorocenols A (1) and B (2) were isolated along with four known isoprenylated phenols, kuwanon C, artonin D, sorocein B, and kuwanol E. The structures of sorocenols A and B were shown to be 1 and 2, respectively. Sorocenol (2) is regarded biogenetically as variation of Diels-Alder type adduct between chalcone derivative and dehydroisoprenylated compound.

PDF (215KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.1045-1049
Published online:
DOI: 10.3987/COM-95-7041
Synthesis of 1H-Indolyl-2-benzimidazoles and 1H-Indolyl-2-benzothiazoles

Robert L. Hudkins*

*Department of Chemistry, Cephalon Inc., 145 Brandywine Parkway, West Chester, PA 19380, U.S.A.

Abstract

A convenient synthesis of regioisomeric 1H-indolyl-2-benzimidazoles and -2-benzothiazoles by the direct conversion of indoleesters with the in situ generated organoaluminum reagents trimethylaluminum-1,2-diaminobenzene or trimethylaluminum-2-aminothiophenol is reported.

PDF (146KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.1051-1070
Published online:
DOI: 10.3987/COM-95-7044
Synthesis of Fused 3a,4-Dihydro-5a,H-benzofuro[3,3a-d]isoxazoles

Kazuho Harada,* Eisuke Kaji, Kuniaki Sasaki, and Shonosuke Zen

*School of Pharmaceutical Sciences, Kitasato University, Shirokane, Minato-ku, Tokyo 108, Japan

Abstract

Reaction of 2-isoxazoline-2-oxides (1) with titanium tetrachloride afforded Diels-Alder dimers (3) of 3a,4-dihydro-5a,H-benzofuro[3,3a-d]isoxazoles (2). The stereochemistry of the dimer (3a) was confirmed by X-ray analysis. As an application of the Diels-Alder reaction, several fused 3a,4-dihydro-5a,H-benzofuro[3,3a-d]isoxazoles (5,6, and 7) were synthesized by the reactions of 2 with acetylenic dienophiles.

PDF (467KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.1071-1076
Published online:
DOI: 10.3987/COM-95-7050
7-Hydroxyrutaecarpine from Tetradium glabrifolium and Tetradium ruticarpum

Tian-Shung Wu,* Jyh-Her Yeh, Pei-Lin Wu, Kuo-Tung Chen, Lie-Chwen Lin, and Chieh-Fu Chen

*Department of Chemistry, National Cheng Kung University, Tainan, Taiwan, R.O.C.

Abstract

A new quinazolinocarboline alkaloid derivative, 7-hydroxyrutaecarpine (1), was isolated from the heatwood of Tetradium glabrifolium and the fruit of Tetradium ruticarpum.

PDF (131KB)
Paper | Regular issue | Vol 41, No. 5, 1995, pp.1077-1084
Published online:
DOI: 10.3987/COM-95-7057
Synthesis of Egonol and (±)-Machicendiol

Yutaka Aoyagi, Toshihiko Mizusaki, Akiko Hatori, Taichi Asakura, Takashi Aihara, Sakae Inaba, Ken Hayatsu, and Akihiro Ohta*

*School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-03, Japan

Abstract

Two norneolignans, egonol (1) and (±)-machicendiol (2) , were synthesized by using the palladium-catalyzed cross-coupling reaction as a key step. This paper describes a new strategy for the preparation of norneolignans having a benzo[b]furan skeleton.

PDF (186KB)
22 data found. 1 - 22 listed