Regular Issue

Vol. 41, No. 8, 1995

21 data found. 1 - 21 listed
Communication | Regular issue | Vol 41, No. 8, 1995, pp.1617-1620
Published online:
DOI: 10.3987/COM-95-7110
An Efficient Synthesis of 4-Trifluoromethylated and 4-Perfluoroalkylated Imidazoles from Mesoionic 1,3-Oxazolium-5-olates

Masami Kawase, Setsuo Saito, and Teruo Kurihara

*Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado-shi, Saitama 350-02, Japan

Abstract

4-Trifluoromethyl- and 4-perfluoroalkylimidazoles (4) were conveniently synthesized from mesoionic 4-trifluoroacetyl- or 4-perfluoroacyl-1,3-oxazolium-5-olate (1) via 2-imidazolines (3), which were formed through the regioselective attack of ammonia on the C(2) position of 1.

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Communication | Regular issue | Vol 41, No. 8, 1995, pp.1621-1626
Published online:
DOI: 10.3987/COM-95-7111
Betavulgarosides I, II, III, IV, and V, Hypoglycemic Glucuronide Saponins from the Roots and Leaves of Beta vulgaris L. (Sugar Beet)

Masayuki Yoshikawa, Toshiyuki Murakami, Masashi Kadoya, Hisashi Matsuda, Johji Yamahara, Osamu Muraoka, and Nobutoshi Murakami

*Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607, Japan

Abstract

Five glucuronide saponins named betavulgarosides I, II, III, IV, and V were isolated from the roots and leaves of Beta vulgaris L. (Sugar beet). Their structures were elucidated on the basis of chemical and physicochemical evidence. Betavulgarosides II, III, and IV and the prosapogenol (6) were found to exhibit hypoglycemic effect on oral glucose tolerance test in rats.

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Communication | Regular issue | Vol 41, No. 8, 1995, pp.1627-1629
Published online:
DOI: 10.3987/COM-95-7138
Palladium-mediated Formation of N-Acyl-2-hydroxyindolines: A New Entry into N-Acylindoles

Kiyohiro Samizu and Kunio Ogasawara

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-77, Japan

Abstract

N-Acyl-2-iodoanilines were reacted with vinylene carbonate in the presenece of palladium(II) acetate to give N-acyl-2-hydroxyindolines, in good yields, which on acid treatment afforded the corresponding N-acylindoles.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1631-1652
Published online:
DOI: 10.3987/COM-93-S(B)16-1
8H-Anhydro-4-hydroxy-2-oxo-1,3-thiazinium Hydroxides as Mesoionic 1,4-Dipoles

Albert Padwa*, Steven J. Coats, and Lazaros Hadjiarapoglou

*Department of Chemistry, Emory University, Atlanta, Georgia 30322, U.S.A.

Abstract

The previously unknown 8H-anhydro-4-hydroxy-2-oxo-1,3-thiazinium hydroxides (1) were prepared and their 1,4-dipolar cycloadditioin behavior was examied. In most cases, elimination of the proton in the 8-position of the mesoionic ring was observed to occur unless extremely reactive dipolarophiles were used. The S,N-ketene acetals were converted to the corresponding α-diazo ketones for further study.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1653-1658
Published online:
DOI: 10.3987/COM-94-7017
Synthesis of 5-Mercaptoalkylamino- and 5-Anilinoalkylthiopyrazolyl-1,2,4-triazoles by Ring Chain Transformation

Zhen-Nian Huang and Zheng-Ming Li

*Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, P. R. China

Abstract

Cyclic α-oxo-α-(1,2,4-triazol-1-yl)ketene N,S-acetals (1a-d) and (4a-d) react with hydrazine by a ring chain transformation affording title compounds (3a-d, 6a-d and 6’a-d).

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1659-1666
Published online:
DOI: 10.3987/COM-95-7023
Photosynthesis of Heteropolycyclic Quinolones

Jasna Dogan, Grace M. Karminski-Zamola, and David W. Boykin

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

Abstract

Four new anilidoquinolones; 9-anilidobenzo[b]thieno[2,3-c]quinolin-6(5H)-one (6), 9-N’-methylanilidobenzo[b]thieno[2,3-c]-5-N-methylquinolin-6-one (7), 9-anilidothieno[4,5-b’]thienyl[2,3-c]quinolin-6(5H)-one (16), and 9-N’-methylanilidothieno[4,5-b’]thienyl[2,3-c]-5-N-methylquinolin-6-one (17) were prepared by photochemical dehydrohalogenation from the dianilides (4, 5, 14 and 15). Photochemical dehydrogenation of the anilides to produce multicondensed diquinolones did not occur.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1667-1673
Published online:
DOI: 10.3987/COM-95-7046
Synthesis of Pyrazolo[3,4-b]pyrazines from 5-Amino-4-nitrosopyrazoles and Dimethylphenacylsulfonium Bromides

Masahiko Takahashi and Masahiko Hatazaki

*Department of Materials Science, Faculty of Engineering, Ibaraki University, Hitachi, Ibaraki 316, Japan

Abstract

Reaction of 1,3-disubstituted 5-amino-4-nitrosopyrazoles (1) with dimethylphenacylsulfonium bromides (2) in boiling pyridine gave 1,3,6-trisubstituted pyrazolo[3,4-b]pyrazine 4-oxides (4) and / or 1,3,6-trisubstituted pyrazolo[3,4-b]pyrazin-5(4H)-ones (5).

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1675-1682
Published online:
DOI: 10.3987/COM-95-7047
Formations of Azazulanones and Dihydroazazulanones via Reactions of Troponimines with Heterocumulenes

Kazuaki Ito, Yasushi Hara, Reiji Sakakibara, and Katsuhiro Saito

*Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso-Cho, Showa-ku, Nagoya 466, Japan

Abstract

Reactions of troponimines with carbon disulfide, phenyl isocyanate, tosyl isocyanate, or diphenylketene afforded dihydroazazulanone and azazulanone derivatives through [8+2]-type cycloadducts. Reaction with dimethyl acetylenedicarboxylate gave a dihydroazazulene derivative and a quinoline derivative.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1683-1689
Published online:
DOI: 10.3987/COM-95-7048
Synthesis of Enol Carbonates from a Reaction of Silyl Enolates with 1H-Imidazolylurethane

Shunsaku Ohta, Masayuki Yamashita, Nobuaki Nagai, Ikuo Kawasaki, Kazuto Maeda, and Yoshiko Miyano

*Kyoto Pharmaceutical University, Misasagi Nakauchicho 5, Yamashinaku, Kyoto 607, Japan

Abstract

Enol Carbonates (6) were prepared by treatment of trimethylsilyl enolates (5) with 1-alkoxycarbonyl-1H-imidazoles (2) in the presence of boron trifluoride etherate and tetrabutylammonium fluoride.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1691-1707
Published online:
DOI: 10.3987/COM-95-7079
Design and Synthesis of Sequence-specific DNA Minor Groove Recognizing Ligands of the Cross-linked Lexitropsin Class

Yong-Huang Chen and J. William Lown

*Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2

Abstract

On the basis of previous studies on pyrrole-containing cross-linked lexitropsins, symmetric and non-symmetric cross-linked lexitropsins incorporating imidazole rings are designed to bind selectively to GC-containing oligonucleotide sequences and their syntheses are described.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1709-1714
Published online:
DOI: 10.3987/COM-95-7081
The First Formation of Diazepinodiazepine and Diazepinodiazocine from Allenedicarboxylate and Acyclic Triamines and Their Conversion to 12- and 13-Membered Ring Compounds

Tadashi Okawara, Shuji Ehara, Aya Takenaka, Tomoko Hiwatashi, and Mitsuru Furukawa

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

Abstract

The reaction of dimethyl allenedicarboxylate (1) with acyclic triamies (2) afforded a diazepinodiazepine (3a) a diazepinodiazocine (3b), which were converted to the 12- and 13-membered compounds (4a-b).

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1715-1719
Published online:
DOI: 10.3987/COM-95-7085
Chirospecific Synthesis of 2R,5S-Dihydroxymethyl-3R,4R-dihydroxypyrrolidine

Ki Hun Park

*Department of Chemistry, Gyeongsang National University, Chinju, Korea 660-701

Abstract

2R,5S-Dihydroxymethyl-3R,4R-dihydroxypyrrolidine (1) has been prepared from D-glucosamic acid which has four stereocenters in the same absolute stereochemistry as required for 1.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1721-1730
Published online:
DOI: 10.3987/COM-95-7088
Synthesis to 1-Substituted 3,4-Diarylisoquinoline Derivatives

Martine Croisy Delcey, Christiane Huel, and Emile Bisagni

*URA 1387 CNRS, Institut Curie, Section de Biologie, Batiments 110-112, 15 rue Georges Clémenceau, 91405 Orsay, France

Abstract

3,4-Diaryl-2H-isoquinolin-1-ones and corresponding 1-chloro derivatives were easily prepared in a way involving i) condensation of 2-aroylbenzyl chlorides with arylmethylamines; ii) treatment of the resulting 1-aryl-N-1-hydroxyarylmethylisoindol-3-ones with LDA leading to an opening reaction and subsequent ring closure; iii) dehydration in boiling formic acid which generally provided the expected isoquinolones in good yields; iv) chlorination of the 2H-isoquinolin-1-ones by phosphorous oxychloride. In the cases of unsymmetrical 4-hydroxy-3-(4-methoxyphenyl)-4-phenyl- and 4-hydroxy-4-(4-methoxyphenyl)-3-phenyl-1,2,3,4-tetrahydroisoquinolin-1-ones a partial and unexpected double aryl migrations (3 → 4) and (4 → 3) were observed.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1731-1742
Published online:
DOI: 10.3987/COM-95-7099
Asitribin and Asiminenins A and B, Novel Bioactive Annonaceous Acetogenins from the Seeds of Asimina triloba

Mi Hee Woo, Lu Zeng, and Jerry L. McLaughlin

*Department of Medicinal Chemistry and Pharmacognosy, School of Pharmacy and Pharmacal Sciences, Purdue University, West Lafayette, IN 47907, U.S.A.

Abstract

A novel bioactive adjacent bis-tetrahydrofuran (THF) acetogenin, asitribin (1), and two novel bioactive mono-THF acetogenins with double bonds, asiminenins A (2) and B (3), were isolated from the seeds of Asimina triloba (Annonaceae) by directing the fractionation with brine shrimp lethality. In addition, asimicin, bullatacin, trilobacin (4) and trilobin (5), which are known, and parviflorin, which is known but is new in this species, were obtained. 1 has an erythro configuration between the two THF rings, as do trilobacin (4) and trilobin (5), and is a structural isomer of 4 and 5. 1 showed potent cytotoxicities among six human solid tumor cell lines with notable selectivity for the lung cell line (A-549). 2 and 3 also exhibited potent and selective bioactivities across the six cell lines. 3 with the trans configuration of the mono-THF ring was more bioactive and selective than 2 with the cis configuration.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1743-1755
Published online:
DOI: 10.3987/COM-95-7101
Goniodenin, a New Bioactive Annonaceous Acetogenin from Goniothalamus giganteus and Its Conversion to Tri-THF Acetogenins

Yan Zhang, Lu Zeng, Mi-Hee Woo, Zhe-Ming Gu, Qing Ye, Feng-E Wu, and Jerry L. McLaughlin

*Department of Medicinal Chemistry and Pharmacognosy, School of Pharmacy and Pharmacal Sciences, Purdue University, West Lafayette, IN 47907, U.S.A.

Abstract

Using activity-directed fractionation, a novel bioactive bis-THF acetogenin, goniodenin (1), has been isolated from the bark of Goniothalamus giganteus (Annonaceae). 1 is the first reported bis-THF acetogenin which bears a double bond in the aliphatic chain. The cis C-21/22 double bond in 1 was efficiently oxidized to the epoxides and cyclized to produce a pair of tri-THF acetogenins, cyclogoniodenins T and C (8 and 13). These are the first reported semi-synthesized tri-THF acetogenins, and 13 represents a new type of acetogenin. The absolute stereochemistries were assigned using Mosher ester and nmr analyses. 8 and 13 show interesting selectivities among several human tumor cell lines. Asimilobin (19), concurrently found in the seeds of Asimina triloba, was also isolated and characterized.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1757-1769
Published online:
DOI: 10.3987/COM-95-7109
Regioselective Acylation of 2,5-Diamino-3-cyano-11H-pyrido[2,3-b][1,5]benzodiazepine and Structural Determination by X Ray Analysis

Yoshihisa Okamoto, Yoshimi Zama, Kaname Takagi, Yoshihisa Kurasawa, Kazuho Harada, and Atsushi Takada

*Division of Chemistry, College of Liberal Arts and Sciences, Kitasato University, 1-15-1, Kitasato, Sagamihara-shi, Kanagawa-ken 228, Japan

Abstract

The acylation of 2,5-diamino-3-cyano-11H-pyrido[2,3-b][1,5]benzodiazepine (1) with acid anhydrides selectively gave the 5-acylamino derivatives (2a-d and 3). The structure of 3 was determined by X ray analysis. A similar reaction of 1 with chloroacetic anhydride afforded a bridgehead double bonded compound (4) via acylation at the 5-amino group of 1. Cyclic anhydrides also reacted with 1 at the 5-amino group to provide the 5-imido derivatives (5a,b and 6). The reaction of 1 with maleic anhydride unexpectedly afforded the 2,3-dimethylmaleimido derivative (12).

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1771-1778
Published online:
DOI: 10.3987/COM-95-7113
An Efficient Synthesis of (S)-(-)-2,8-Dimethyl-3-methylene-1-oxa-8-azaspiro[4.5]decane by Cobaloxime(I)-mediated Radical Cyclization

Shin-ichi Tsukamoto, Yutaka Kondo, and Susumu Igarashi

*Institute for Drug Discovery Research, Yamanouchi Pharmaceutical Co., Ltd., 21, Miyukigaoka, Ibaraki 305, Japan

Abstract

Optically pure (S)-(-)-2,8-dimethyl-3-methylene-1-oxa-8-azaspiro[4.5]decane (1) was synthesized by alkoxybromination of 1-ethoxycarbonyl-4-methylenepiperidine (4) with (S)-3-butyn-2-ol and N-bromosuccinimide followed by radical cyclization mediated by cobaloxime(I) in 15% overall yield. Reaction conditions for the alkoxybromination reaction were devised to reduce the requirement of the optically pure alcohol.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1779-1784
Published online:
DOI: 10.3987/COM-95-7114
Reactivity of Bis(heteroaryl)methanes towards Double Electrophiles. Synthesis of Two New Trinuclear [5.6.5]- and [5.5.5]-heterocyclic Systems from Bis(pyrazol-1-yl)methane

Enrique Díez-Barra,* María José Gómez-Escalonilla, Antonio de la Hoz, Andrés Moreno, and Juan Tejeda

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

Abstract

Two new trinuclear [5.6.5]- and [5.5.5]-heterocyclic systems have been synthesized from bis(pyrazol-1-yl)methane. The scope of this process has been studied. A new desilylating-oxidating system [CuF2/acetonitrile: pyridine (2:1)] is described.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1785-1796
Published online:
DOI: 10.3987/COM-95-7117
Absolute Stereochemistries of Sylvaticin and 12,15-cis-Sylvaticin, Bioactive C-20,23-cis Non-adjacent Bistetrahydrofuran Annonaceous Acetogenins, from Rollinia mucosa

Guoen Shi, Lu Zeng, Zhe-ming Gu, John M. MacDougal, and Jerry L. McLaughlin

*Department of Medicinal Chemistry and Pharmacognosy, School of Pharmacy and Pharmacal Sciences, Purdue University, West Lafayette, IN 47907, U.S.A.

Abstract

A new acetogenin, 12,15-cis-sylvaticin (2), and its stereoisomer, sylvaticin (1), a known acetogenin whose stereochemical structure has remained unsolved until now, were isolated, using activity-directed fractionation, from the leaf extracts of Rollinia mucosa (Jacq.) Baill. (Annonaceae). 1 is cis at C-20, 23 and trans at C-12, 15; 2 is cis at C-20, 23 and C-12, 15. A key step in solving their absolute stereochemistries was the determination of the relative configurations (cis or trans) of their 1,4-diols; this was achieved by a new procedure using the pattern recognition of the NOSEY spectra of their 1,4-diol formaldehyde acetal derivatives (1b and 2b). Both 1 and 2 showed potent and selective cytotoxicities, against the A-549 lung cancer and the PACA-2 pancreatic cancer, in a panel of six human solid tumor cell lines.

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Paper | Regular issue | Vol 41, No. 8, 1995, pp.1797-1804
Published online:
DOI: 10.3987/COM-95-7132
Asymmetric Synthesis of Indolizidines 167B and 223AB

Hiroki Takahata, Hiroshi Bandoh, and Takefumi Momose

*Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Sugitani 2630, Toyama 930-01, Japan

Abstract

The total synthesis of (+)-indolizidine 167B (1) and the formal synthesis of (-)-indolizidine 223AB (2) starting with L- and D-norvaline-derived cis-2-hydroxymethyl-6-propylpiperidines (3 and ent-3), respectively, are described.

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Review | Regular issue | Vol 41, No. 8, 1995, pp.1805-1832
Published online:
DOI: 10.3987/REV-95-471
Tautomerism and Isomerism of Heterocycles [1]

Yoshihisa Kurasawa, Atsushi Takada, and Ho Sik Kim

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

Abstract

This review describes the various tautomerism and isomerism of diverse heterocyclic compounds in solution and solid state, which are classified into several sections as shown in the subject contents.

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21 data found. 1 - 21 listed