Regular Issue

Vol. 29, No. 8, 1989

26 data found. 1 - 26 listed
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1435-1438
Published online:
DOI: 10.3987/COM-89-4987
Normavacurine and Minfiensine, Two New Alkaloids with C19H22N2O Formula from Strychnos Species

Georges Massiot,* Philippe Thépenier, Marie-José Jacquier, Louisette Le Men-Olivier, and Clément Delaude

*Laboratorie de Pharmacognosie, Facluté de Pharmacie, U.A. n°492 au C.N.R.S., 51, rue Cognacq-Jay, F-51096 Reims Cedex, France

Abstract

Minfiensine and normavacurine are two novel C19H22N2O alkaloids from Strychons minfiensis, S. potatorum and S. longicaudata. Minfiensine is characterized by a N-1 - C-3 bond instead of the usual N-1 - C-2 bond.

PDF (96KB)
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1439-1441
Published online:
DOI: 10.3987/COM-89-4997
An Alternative Model for the Biogenesis of Xanthanolides

Antonio G. González, Antonio Galindo,* María del Mar Afonso, amd Horacio Mansilla

*Centro de Productos Naturales Orgánicos "Antonio González", Universidad de La Laguna, Avda. Astrofísico Franciso Sánchez, 2, 38206- La Laguna, Tenerife, Spain

Abstract

Hydroperoxide transposition of 4-hydroperoxyguaianolide (10) afforded xanthanolide (12). The possible biogenetic implications of this process are discussed.

PDF (61KB)
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1443-1446
Published online:
DOI: 10.3987/COM-89-4996
Reaction of 6-Methyl-2-phenyl-4H-1,3-oxazin-4-one with Oxime Dianions

Yutaka Yamamoto,* Yasuo Morita, Reiko Kikuchi, Emiko Yokoo, Kaori Ohtsuka, and Miwako Katoh

*Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan

Abstract

6-Methyl-2-phenyl-4H-1,3-oxazin-4-one (1) undergoes novel ring transformation upon treatment with oxime dianions to give isoxazoles (3a-d) and pyridine N-oxides (4c-f). The reaction of 1 with cycloheptanone oxime (2a) or cyclododecanone oxime (2b) in the presence of two equivalents of butyllithium affords isoxazole (3a or 3b). With acetophenone oxime (2c) or acetoxime (2d), pyridine N-oxide (4c or 4d) is formed as a minor product in addition to isoxazole (3c or 3d). Treatment with cyclopentanone oxime (2e) or cyclohexanone oxime (2f) yields pyridine N-oxides (4e or 4f) as a sole product.

PDF (88KB)
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1447-1453
Published online:
DOI: 10.3987/COM-89-5019
Artonins A and B, Two New Prenylflavonoes from the Root Bark of Artocarpus heterophyllus Lamk

Yoshion Hano, Miwa Aida, Mikako Shiina, Taro Nomura,* Takatoshi Kawai, Hiroshi Ohe, and Kengo Kagei

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

Abstract

Two new prenylflavones, artonins A (1) and B (2), were isolated from the root bark of Artocarpus heterophyllus Lamk. (Moraceae), along with two known prenylflavones, heterophyllin (3) and cycloheterophyllin (4). The structures of artonins A and B were shown to be 1 and 2, respectively, on the basis of the X-ray crystallographic analysis, spectroscopic data, and chemical evidence.

PDF (165KB)
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1455-1458
Published online:
DOI: 10.3987/COM-89-5028
Synthesis and Reaction of 3-Hydroxyenamides

Shunsaku Ohta,* Motoshige Sumino, Tsutomu Sasaki, and Nobuyuki Yamagami

*Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8412, Japan

Abstract

3-Hydroxyenamides (7) were prepared starting from 1,3-dicarbonyl compounds (4), and the enamides (7) readily reacted with π nucleophiles in the presence of trifluoroacetic anhydride to give 3-arylketones (11) in moderate yields.

PDF (75KB)
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1459-1464
Published online:
DOI: 10.3987/COM-89-5034
Polyannulated Tropylium Compounds Having Benzothiazine and Related Heterocyclic Rings. Formation of o- and p-Benzoquinonoid Products by Rearrangement

Tetsuo Nozoe,* Kimio Shindo,* Hidetsugu Wakabayashi, and Sumio Ishikawa

*Department of Chemistry, Faculty of Science, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan

Abstract

Tropylium compounds having tri-annulated heterocycles (11 and 15) are obtained by the reaction of 2,4-dibromo-7-methoxy- and 3,5,7-tribromo-2-methoxytropone with O-aminophenol and O-aminobenzenethiol, via di-annulated compounds. Rearrangements to di- and tri-annulated o- and p-benzoquinonoid compounds (13, 16 and 20) take place during the attempted synthesis of some tri-annulated tropylium systems. Possible pathways for these reactions are discussed.

PDF (143KB)
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1465-1468
Published online:
DOI: 10.3987/COM-89-5052
Structure and Stereochemistry of Emargiatine-A, a Novel Cytotoxic Sesquiterpene Pyridine Alkaloid from Maytenus emarginata: X-Ray Crystal Steructure of Emarginatine-A Monohydrate

Yao-Haur Kuo, Chung-Hsiung Chen, Li-Ming Yang Kuo, Ming-Lu King, Tian-Shung Wu, Sheng-Teh Lu, Ih-Sheng Chen, Donald R. McPhail, Andrew T. McPhail,* and Kuo-Hsiung Lee*

*Division of Medicinal Chemistry and Natural Products, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7360, U.S.A.

Abstract

The structure and stereochemistry of emarginatine-A (1), a novel cytotoxic sesquiterpene pyridine alkaloid isolated from Maytenus emarginata, have been established from spectral data in conjunction with a single-crystal X-ray analysis of its monohydrate.

PDF (95KB)
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1469-1472
Published online:
DOI: 10.3987/COM-89-5057
Synthesis of (+)-1-Deoxynojirimycin from (S)-Pyroglutamic Acid

Nobuo Ikota*

*National Institute of Radiological Sciences, 9-1, Anagawa-4-Chome, Inage-ku, Chiba 263-0024, Japan

Abstract

The synthesis of (+)-1-deoxynojirimycin (10) has been achieved from (S)-pyroglutamic acid by cis hydroxylation of the trans-α,β-unsaturated ester 2 and reduction of the enone 5b as the key reactions. 5-O-Carbamoylpolyoxamic acid (14) and (+)-1-deoxymannojirimycin (11) were also synthesized from 4b and 7b, obtained by the above reactions as the minor diastereomer, respectively.

PDF (103KB)
Communication | Regular issue | Vol 29, No. 8, 1989, pp.1473-1476
Published online:
DOI: 10.3987/COM-89-5064
A Concise Enantioselective Synthesis of Acromelic Acid B from (S)-O-Benzylglycidol

Seiichi Takano,* Shun’ichi Tomita, Yoshiharu Iwabuchi, and Kunio Ogasawara

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan

Abstract

The potent neurotoxin, acromelic acid B, has been synthesized by an enantioselective route employing an intramolecular 1,3-dipolar cyclization as the key step.

PDF (127KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1477-1487
Published online:
DOI: 10.3987/COM-89-4933
Syntheses of Functionalized Derivatives of Quinazolines and 1,4-Bensodiazepines

Maurizio Anzini, Antonio Garofalo, and Salvatore Vomero*

*Dipartimento Farmaco Chimico Technlogico, Università degli Studi di Siena, Banchi di Sotto, 55 - 53100 Siena, Italy

Abstract

The 2-substituted 1,4-benzodiazepines (4 and 6) were synthesized. The reaction of 2-aminobenzophenone oximes with ethyl 4-chloroacetoacetate gave the 1,4-benzodiazepines (4) and the 1,2-dihydroquinazolines (5); the latter were treated with a base to result ring expansion giving the 1,4-benzodiazepines (6).

PDF (197KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1489-1495
Published online:
DOI: 10.3987/COM-89-4944
Three New Clerodane-type Diterpenoids, Clerodinin C, Clerodinin D and Clerodiol, from Clerodendron brachyanthum Schauer

Yun-Lian Lin, Yueh-Hsiung Kuo,* and Yuh-Lin Chen

*Department of Chemistry, National Taiwan University, Roosevelt Road Section 4, Taipei 106, Taiwan, R.O.C.

Abstract

Clerodinin C, clerodinin D and clerodiol, three new clerodane-type diterpenoids have been isolated from the hexane extract of the leaves of Clerodendron brachyanthum Schauer. Their structures have been elucidated by means of spectroscopic and chemical evidence.

PDF (165KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1497-1516
Published online:
DOI: 10.3987/COM-89-4947
Design and Synthesis of 4-Oxoquinolin-2-yl-6-heptenoic Acid Derivatives as HMG-CoA Reductase Inhibitors

Gary M. Coppola,* Terrence J. Scallen, Ann DelPrete, and Rita Montano

*Sandoz Research Institute, Sandoz, Inc., Route 10, East Hanover, New Jersey 07936, U.S.A.

Abstract

Syntheses of two isomeric series of 4-oxoquinolin-2-yl-6-heptenoic acid derivatives 7 and 8 are described. The quinolinone portion of the molecules was constructed from the reaction of either an N-alkyl- or N-arylisatoic anhydride with an appropriate ketone enolate. The side-chain was elaborated by way of an aldol condensation using ethyl acetoacetate dianion fllowed by stereoselective ketone reduction. The N-aryl series 8 exhibited significantly greater inhibitory activity than the N-alkyl series 7.

PDF (424KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1517-1528
Published online:
DOI: 10.3987/COM-89-4984
Synthesis and Cardiotonic Activity of 5-(2-Substituted Thiazol-4-yl)-2-pyridones and Thiazolo[4,5-f]quinolinones

Hiroshi Fukatsu,* Yoshiaki Kato, Satoshi Murase, and Susumu Nakagawa

*Okazaki Research Laboratories, Banyu Pharmaceutical Co., Ltd., 3-9-1, Kamimutuna, Okazaki, Aichi 444, Japan

Abstract

A variety of 5-(2-substituted thiazol-4-yl)-2-pyridones and thiazolo[4,5-f]quinoliiones were synthesized and tested in vitro for cardiotonic activity. Several compounds of these series showed good positive inotropic activity.

PDF (237KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1529-1536
Published online:
DOI: 10.3987/COM-89-4990
Synthesis of Sulfonamide Analogs of the Pyrrolo[1,4]benzodiazepine Antibiotic Abbeymycin

Nicole Langlois and Ratremaniaina Z. Andriamialisoa

*Institut des Chimie des Substances Naturelles, C.N.R.S., 1 avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France

Abstract

Sulfonamide analogs of antitumor antibiotics of the pyrrolo[1,4]benzodiazepine group were prepared from (S)-prolinol as carbinolamine ethers.

PDF (176KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1537-1543
Published online:
DOI: 10.3987/COM-89-4994
Reactions of Diazo Compounds of Heterocyclic Aldehydes with Phenylacetylene: Formation of Pyrazoles Combined with Heterocycles

Katsuhiro Saito,* Hiroshi Fushihara, Tatsuji Sato, Hiraku Ishihara, and Kensuke Takahashi

*Faculty of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan

Abstract

Reactions of sodium salts of 2- and 3-thiophenecarbaldehyde tosylhydrazone and furfural tosylhydrazone with phenylacetylene afforded pyrazoles combined with thiophene and furan moieties via 1,3-dipolar cycloadditions of the corresponding diazo compounds.

PDF (148KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1545-1550
Published online:
DOI: 10.3987/COM-89-5001
Reactions of Pyrazole and Pyrrole Derivatives with Trimethylchlorosilane

Katsuhiro Saito,* Yoichi Horie, Toyonobu Murase, and Kensuke Takahashi

*Faculty of Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan

Abstract

Reactions of 1-carbomethoxypyrazole and 1-carbomethoxypyrrole with trimethylchlorosilane in hexamethylphosphortriamide in the presence of magnesium afforded the parent compounds, respectively, eliminating the substituents. The similar reaction using 1-methylpyrazole gave 1-methyl-5-trimethylsilylpyrazole through a substitution reaction. The reactions are considered to proceed via radical anions of the heterocycles formed by electron transfers from magnesium.

PDF (143KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1551-1558
Published online:
DOI: 10.3987/COM-89-5003
Imidazole Derivatives. Part II. Synthesis of Imidazo[1,2-a]pyridin-5-ones

Hans-Joachim Knölker,* Roland Boese, and Rainer Hitzemann

*Institut für Organische Chemie, Universität Hannover, Schneiderberg 1b, D-30167 Hannover, Germany

Abstract

The reaction of 2-phenacylimidazole with acetylenic esters provides imidazo[1,2-a]pyridin-5-ones by an one-pot procedure.

PDF (180KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1559-1571
Published online:
DOI: 10.3987/COM-89-5004
Reactions of Ethyl 2-Hydroxy-4-(4-hydroxy-6-methyl-2-pyron-3-yl)-4-oxo-2-butenoate with N-Nucleophiles. Synthesis of Isomeric Pyronylpyrazoles and Pyrano[4,3-c]pyrazoles

Ana Brbot-Saranovic,* Branka Katusin-Razem, and Ivana Susnik

*Institute "Ruder Boskovic", University of Zagreb, 411000 Zagreb, Croatia

Abstract

Reaction of the title compound 1 with aniline gave two Schiff’s bases 2 and 3, while condensation of 1 with phenylhydrazine afforded four products 4 - 7. Compounds 4 and 6 were formed after initial nucleophilic attack at the central carbonyl carbon of tricarbonylic moiety, while 5 and 7 were formed after initial attack at the 4-position of the 2-pyrone ring. These structures were confirmed by the selective preparation of 4 - 7 from pyranopyrandiones 12 and 13, respectively. Pyrazole-4-carboxylic acid derivatives 6 and 7 cyclize in acetic anhydride into fused pyrano[4,3-c]pyrazoles 8 and 9, respectively. Their structures were compared with that of the parent 3-methyl congeners 14 and 15, obtained from dehydraacetic acid.

PDF (279KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1573-1576
Published online:
DOI: 10.3987/COM-89-5005
Phase-transfer Catalysed Alkylation of 3-Hydroxycoumarin

Krishna C. Majumdar,* Abu T. Khan, and Shital K. Chattopadhyay

*Department of Chemistry, University of Kalyani, Kalyani 741 235, West Bengal, India

Abstract

Phase-transfer catalysed alkylarion of 3-hydroxycoumarin with active alkyl halides gave O-alkylated products (45-60%), C-alkylated products (20-40%) and in one case C,O-dialkylated product (20%).

PDF (95KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1577-1582
Published online:
DOI: 10.3987/COM-89-5006
The Structure of Two New Diterpenoid Alkaloids from Aconitum napellus L. S. Str.

Gabriel de la Fuente,* Matías Reina, and Emir Valencia

*Instituto de QUímica Orgánica, Instituto de Productos Naturales Orgánicos, C. S. I. C./ Unversidad de La Laguna, La Laguna, Tenerife, Canary Islands, Spain

Abstract

From aerial parts of Aconitum napellus L. s. str. (syn. A. anglicum Stapf) were isolated two new diterpenoid alkaloids, 8-O-ethylbenzoylaconine (1) and 15-acetyl-13-dehydracardiopetamine (3), besides cardiopetamine (5), 15-acetylcardiopetamine (4), songoramine (6), and songorine (7). The structures were established by 1H - and 13C-nmr and confirmed by partial synthesis.

PDF (134KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1583-1588
Published online:
DOI: 10.3987/COM-89-5016
Ring Transformation of 5-Acylpyrimidines into 4-Acylpyrazoles with Phenylhydrazine

Abdelilah Bajnati, Michel Hubert-Habart,* Kaname Takagi, and Hiroshi Terada

*Section de Physique et Chimie, Institut Curie, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, France

Abstract

Phenylhydrazine in alcoholic acidic medium exclusively transformed 5-benzoyl-4-methyl-2-methylthiopyrimidine into 4-acetyl-1,3-diphenylpyrazole and 5-acetyl-2-methylthio-4-phenylpyrimidine into 4-benzoyl-3-methyl-1-phenylpyrazole. The mechanism of these ring contraction reactions is proposed.

PDF (138KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1589-1593
Published online:
DOI: 10.3987/COM-89-5017
Synthesis of Vinca Alkaloids and Related Compounds, XLV. A New Heterocyclic Ring System

Zsuzsanna Kardos-Balogh, Ferenc Sóti, Mária Incze, Mária Kajtár-Peredy, and Csaba Szántay*

*Institute of Chemistry, Chemical Research Center, Hungarian Academy of Sciences, H-1025 Budpest II, Pusztaszeri ut 59-67, P.O. Box 17, Hungary

Abstract

The indole derivative 1 rearranges under acidic conditions to a new heterocyclic ring system (2). On reacting the Latter with LAH a second rearrangement takes place, and compound 3 is formed.

PDF (104KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1595-1600
Published online:
DOI: 10.3987/COM-89-5023
New Synthetic Approach to Pyrazolo[3,4-d]pyridazin-7(6H)-one Ring System

Vittorio Dal Piaz,* Giovanna Ciciani, Maria Paola Giovannoni, and Giovanni Turco

*Dipartimento di Scienze Farmaceutiche, Università di Ferrara, via Fossato di Mortara 17, I-44100, Ferrara, Italy

Abstract

Treatment of 2,6-disubstituted 5-acetyl-4-nitropyridazin-3(2H)-ones (2a-b) with hydrazine or substituted hydrazines in alcoholic medium gives rise in high yields to new 1H- and 2H-pyrazolo[3,4-d]pyridazin-7(6H)-ones (1a-f).

PDF (142KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1601-1605
Published online:
DOI: 10.3987/COM-89-5025
Convenient Preparations of 1,8-Dioxo-6-thioxopimerazino[1,2-c]perhydropyrimidines

Tadashi Ohkawara, Shigenori Matsumoto, Tetsuo Yamasaki,and Mitsuru Furukawa

*Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-hon-machi, Kumamoto 862-0973, Japan

Abstract

Hydrolysis of 4-thiocarbamoyl-3-ethoxycarbonylmethylpiperazin-2-ones 3 in alkaline solution followed by acidification afforded 1,8-dioxo-6-thioxopiperazino[1,2-c]perhydropyrimidines 4 in 65-85% yields.

PDF (102KB)
Paper | Regular issue | Vol 29, No. 8, 1989, pp.1607-1613
Published online:
DOI: 10.3987/COM-89-5056
Preparation of [1,2,4]Triazolo[5,1-c][1,2,4]triazine Derivatives from 3,4-Diamino[1,2,4]triazine

Pedro Molina,* Mateo Alajarín, Ma Jesús Pérez de Vega, and Antonio López

*Departmento de Química Orgánica, Facultad de Ciencias, Universidad de Murcia, 30071 Murcia, Spain

Abstract

3,4-Diamino[1,2,4]triazine 1 reacts with diarylcarbodiimides to give the 7-arylamino-3-methyl-8H-4-oxo[1,2,4]triazolo[5,1-c][1,2,4]triazines in good yields. The reaction of the iminaphosphorane 4 with thioureas leads directly to 2 in moderate yields.

PDF (136KB)
Review | Regular issue | Vol 29, No. 8, 1989, pp.1615-1648
Published online:
DOI: 10.3987/REV-89-393
Pyrazole 1-Oxides, 1,2-Dioxides and Derivatives

Antigoni Kotali and Petros G. Tsoungas

*Laboratory of Organic Chemistry, College of Engineering, University of Thessaloniki, Thessaloniki 54006, Greece

Abstract

Structure, syntheses, spectroscopic properties and the chemical reactivity of the N-oxides of the pyrazole nucleus are described.

PDF (591KB)
26 data found. 1 - 26 listed