Regular Issue

Vol. 19, No. 12, 1982

23 data found. 1 - 23 listed
Communication | Regular issue | Vol 19, No. 12, 1982, pp.2247-2250
Published online:
DOI: 10.3987/R-1982-12-2247
Sulfer Dioxide Insertion into γ-Functional Vinylic Grinard Reagents. A Facile Synthesis of α,β-Unsaturated γ-Sultines and γ-Sultones

Elisabeth Thoumazeau, Bernard Jousseaume, Françoise Tiffon, and Jean-Georges Duboudin

*Ecole Nationale Spérieure de Chimie et Physique, Université de Bordeaux I, 351, cours de la Libération, 33405 Talence Cedex, France

Abstract

α,β-Unsaturated γ-sultines were synthesised by insertion of sulfur dioxide into γ-functional vinylic Grignard reagents generated by addition of aliphatic or aromatic organomagnesium compounds to α-acetylenic alcohols. These products are easily oxidized to the corresponding γ-sultones.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2251-2254
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DOI: 10.3987/R-1982-12-2251
Activated Nitriles in Heterocyclic Synthesis: A Novel Synthesis of Pyrazolo[5,6:3’,4’]pyrano[5,4-b]isoxazoles

Suzan Ibraheim Aziz, Bahia Yahia Riad, Hassan Attia Elfahham, and Mohamed Hilmy Elnagdi

*Chemistry Department, Faculty of Science, Minia University, Minia, Egypt

Abstract

A novel synthesis of pyrano[2,3-c]isoxazoles is reported via reaction of 4-arylidene-2-isoxazolin-5-ones with malononitrile and ethyl cyanoacetate. The synthesised isoxazole derivatives were converted into derivatives of new ring system pyrazolo[5,6:3’,4’]pyrano[5,4-b]isoxazole via reaction with hydrazine hydrate.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2255-2257
Published online:
DOI: 10.3987/R-1982-12-2255
Synthesis of Norrufescine

Mary D. Manachery, Michael P. Cava, Keith T. Buck, and William J. Prinz

*Department of Chemistry, University of Pennsylvania, 231 South 34th Street Philadelphia, PA 19104-6323, U.S.A.

Abstract

The phenolic azafluoranthene alkaloid norrufescine 1 has been synthesized. The key step in the synthesis involved the formation of the tetracyclic azafluoranthene nucleus by a novel aprotic thermolysis of a condensed triazine precursor.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2259-2262
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DOI: 10.3987/R-1982-12-2259
Cycloaddition Reactions of Thiazolium N-Dicyanomethylide with Olefinic Dipolarophiles

Otohiko Tsuge, Yoichi Shimizu, Hiroshi Shimoharada, and Shuji Kanemasa

*Research Institute of Industrial Science, Faculty of Engineering, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan

Abstract

The cycloaddition reaction of a stable N-methylide, thiazolium N-dicyanomethylide, with acyclic olefinic dipolarophiles such as dimethyl fumarate, maleate, and trans-1,2-dibenzoylethylene proceeded in a stereoselective manner to give only the corresponding endo-[3 + 2] cycloadducts, all of which were stable in boiling tetrahydrofurn. In the reaction of the methylide with N-substituted maleimides, however, a mixture of endo- and exo-[3 + 2] cycloadducts, whose relative yields changed with the reaction time, was formed. The endo cycloadduct was found to isomerize into the exo cycloadduct in tetrahydrofuran even at room temperature.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2263-2268
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DOI: 10.3987/R-1982-12-2263
Simple Conversion of 8-Alkyl-8,14-cycloberbines to Spirobenzylisoquinolines by Regioselective C-N Bond Cleavage

Miyoji Hanaoka, Shun-ichiro Sakurai, Yuko Sato, and Chisato Mukai

*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan

Abstract

On acidic treatment the 8-alkyl-8,14-cycloberbines (10) were converted easily to the spirobenzylisoquinolines (11, 12, or 13) in good yields. Reduction of 10 gave stereoselectively the diastereoisomeric alcohols (14 or 15) depending on the reagents, NaBH4 or LiA1H (OBUt)3, respectively. The both alcohols afforded also corresponding spirobenzylisoquinolines with acids.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2269-2273
Published online:
DOI: 10.3987/R-1982-12-2269
IAC Reactions in the Indole Series: Total Synthesis of Clavicipitic Acid

Alan P. Kozikowski and Michael N. Greco

*Department of Chemistry, University of Pittsburgh, Parkman Avenue & University Drive, Pittsburgh, PA 15260 , U.S.A.

Abstract

The first total synthesis of clavicipitic acid (1), a derailment product of ergoline biosynthesis, has been accomplished through an intramolecular azide cycloaddition reaction. The 3,4-disubstituted indole required for this work was assembled from indole-4-carboxaldehyde. The single imine generated from the [3+2] cycloaddition reaction was subjected to bromination, dehydrobromination, reduction and hydrolysis to afford clavicipitic acid (~1:1 mixture of the cis and trans-isomers).

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2275-2278
Published online:
DOI: 10.3987/R-1982-12-2275
Photochemical Ring Opening Rreactions of 3-Alkoxyisocoumarin and 3-Halo-1-isoquinolone

Chikara Kaneko, Toshihiko Naito, and Chiemi Miwa

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

Abstract

Irradiation of 3-methoxyisocoumarin (1) in an alcohol afforded two kinds of diester of homophthalic acid (3 and 4) and the mechanism including novel 1,5-sigmatropic methoxy rearrangement from initially formed ketene (5) to the isomeric ketene (6) was proposed. Similar photochemical ring opening reaction of 3-chloro- and -bromo-1-isoquinolones (8 and 9) as well as their novel photoalkoxylation reaction is also described.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2279-2282
Published online:
DOI: 10.3987/R-1982-12-2279
A New Synthesis of (±)-Lysergic Acid

Toshiko Kiguchi, Chiyomi Hashimoto, Takeaki Naito, and Ichiya Ninomiya

*Kobe Women’s College of Pharmacy, Motoyamakita, Higashinad, kobe, Hyogo 658, Japan

Abstract

Reductive photocyclization of the enamide (2) followed by the ring opening of the resulting dihydrofuran derivative (4) completed a new total synthesis of (±)-lysergic acid.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2283-2286
Published online:
DOI: 10.3987/R-1982-12-2283
An Improved Conversion of 1,4,6-Trisubatituted 2(1H)-Pyrimidinones into the Corresponding Thiones

Akira Katoh, Choji Kashima, and Yoshimori Omote

*Department of Chemistry, University of Tsukubaa, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan

Abstract

1,4,6-Trisubstituted 2(1H)-pyrimidinones (2a-j) are easily converted into the corresponding thiones (3a-j) in high yields by reacting with 2,4-bis(p-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (1). Further, other diazines, e.g., 2-methyl-6-phenyl-3(2H)-pyridazinone (4) and 1-methyl-5,6-diphenyl-2(1H)-pyrazinone (6) are also converted into the corresponding thiones 5 and 7 in 99 and 91% yield, respectively.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2287-2290
Published online:
DOI: 10.3987/R-1982-12-2287
The Revised Structure of Paniculine

Orland Muñoz and Mariano Castillo

*Departamento de Química, Facultad de Ciencias, Unversidad de Chile, Casilla 653, Santiago, Chile

Abstract

The original structure of paniculine has been revised based upon additional physical data.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2291-2294
Published online:
DOI: 10.3987/R-1982-12-2291
A Facile Conversion of the 1-Methyl Group to the 1-Amino Group of Xanthine Derivatives

Taisei Ueda, Noriichi Oda, Jinsaku Sakakibara, and Kazumi Takeya

*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan

Abstract

A facile conversion of the 1-methyl group to the 1-amino group of caffeine and its analogues was carried out by the reaction with hydrazine hydrate: Refluxing of caffeine(Ia) with a large amount of hydrazine hydrate (30 eq. mole) without any other solvents gave 1-amino-3,7-dimethylxanthine(IIa) in 40% yield. Similarly the reaction of 7-substituted 1,3-dimethylxanthines(Ib,Id-f) with hydrazine hydrate gave 7-substituted 1-amino-3-methylxanthines(IIb,IId-f) in 28-42% yield. Deamination of these 7-substituted 1-amino-3-methylxanthines (IIa-b, IId-f) gave the corresponding theobromine derivatives (IVa-b,IVd-f) in 90-96% yield.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2295-2300
Published online:
DOI: 10.3987/R-1982-12-2295
A Convenient Synthesis of 6-Methylellipticine and 6-Methylolivacine

Martin J. Wanner, Gerrit-Jan Koomen, and Upendra K. Pandit

*Organic Chemistry Laboratory, University of Amsterdam, Nieuwe Achtergracht 129, 1018 WS Amsterdam, The Netherlands

Abstract

Readily accessible 11-ketopyrido[4,3-b]carbazole derivatives 3a,b have been used as central intermediates for the synthesis of 6-methylellipticine and 6-methylolivacine.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2301-2304
Published online:
DOI: 10.3987/R-1982-12-2301
Demethylprotoemetinols from Alangium lamarckii

Esahak Ali, Radhika R. Sinha, Basudeb Achari, and Satyesh C. Pakrashi

*Indian Institute of Chemical Biology, Calcutta-700 032, India

Abstract

Structures of two new isomeric alkaloids isolated from the seeds of Alangium lamarckii have been established as 10-demethylprotoemetinol (10) and 9-demethylprotoemetinol (11).

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2305-2308
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DOI: 10.3987/R-1982-12-2305
Syntheses of (—)-9-Demethylprotoemethinol and (±)- and (—)-10-demethylprotoemetinols

Tozo Fujii, Masashi Ohba, Hitoshi Suzuki, Satyesh C. Pakrashi, and Esahak Ali

*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan

Abstract

The synthesis of (—)-9-demethylprotoemetinol (X) was achieved by LiAlH4 reduction of the (—)-tricyclic ester XIV followed by catalytic hydrogenolysis of the resulting (—)-tricyclic alcohol XI. Acetylation of (—)-X yielded the (—)-diacetate XVII. Parallel synthetic routes starting with the isomeric (±)- and (—)-tricyclic esters XV gave (±)- and (—)-10-demethylprotoemetinols (XII) and the corresponding diacetates [(±)- and (—)-XVIII] through the (±)- and (—)-tricyclic alcohols XIII, respectively.

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Communication | Regular issue | Vol 19, No. 12, 1982, pp.2309-2312
Published online:
DOI: 10.3987/R-1982-12-2309
Double Ring-transformation of Uracils to Pyrazolones via Hydantoin Ring System

Kosaku Hirota, Yoshihiro Yamada, Jun-ichi Haruta, and Shigeo Senda

*Labolatory of Medicinal Chemistry, Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan

Abstract

Hydrazinolysis of 3-alkyl-1-aryl-5-bromo-6-methyluracil derivatives (1) causes a novel double ring-transformation to pyrazolones (2) via hydantoin ring system.

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Report | Regular issue | Vol 19, No. 12, 1982, pp.2313-2317
Published online:
DOI: 10.3987/R-1982-12-2313
Heterocyclic Quinones with Potential Antitumor Activity. A Convenient Synthesis of 5,6-Dimethyl-4,7-benzimidazolediones

Ippolito Antonini, Gloria Cristalli, Palmarisa Franchetti, Mario Grifantini, and Sante Martelli

*Department of Chemical Sciences, University of Camerino, Italy

Abstract

Simple syntheses of 1-substituted 5,6-dimethyl-4,7-benzimidazolediones (Ia-c) are described. The commercially available 5,6-dimethylbenzimidazole was alkylated and nitrated. The corresponding 4,7-dinitro derivatives were reduced to diamines and subsequently oxidized to quinones.

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Report | Regular issue | Vol 19, No. 12, 1982, pp.2319-2325
Published online:
DOI: 10.3987/R-1982-12-2319
A New Synthesis of γ-Ylidene-α,β-butenolides from 2-Nitro-5-furancarbaldehyde and Pyrazoles

Maria de Bernadi, Giovanni Vidari, and Paola Vita Finzi

*Dipartamento di Chimica Organica, Università di Pavia, V. le Taramelli 10, 27100 Pavia, Italy

Abstract

A new and rapid synthesis of 5-pyrazolylmethylene-2(5H)furanones by the reaction of 2-nitro-5-furancarbaldehyde (I) with different substituted pyrazoles (IIa-f) in acetic acid-acetic anhydride is described.

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Report | Regular issue | Vol 19, No. 12, 1982, pp.2327-2329
Published online:
DOI: 10.3987/R-1982-12-2327
Regioselective Functionalisation of the Δα,β-Butenolide Ring via Group IV-B Organometallics

Mariella Fiorenza, Alfredo Ricci, M. Novella Romanelli, Maurizio Taddei, Pasquale Dembech, and Giancarlo Seconi

*CNR, Centro di Studio Sulla Chimica e la Struttura dei Composti Eterociclici e lolo Applicazioni, c/o Dipartimento di Chimica Organica “Ugo Schiff”, Università di Firenze, Via Gino Capponi 9, I-50121 Firenze, Italy

Abstract

The Δα,β-butenolide ring reacts with amino- and thiosilanes to give 4-substituted γ-butyrolactone and siloxyfuran. The latter undergoes regiospecific functionalisation at the 5 position with benzaldehyde under F- catalysis.

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Report | Regular issue | Vol 19, No. 12, 1982, pp.2331-2338
Published online:
DOI: 10.3987/R-1982-12-2331
A Study of the Structure of 4-Arylazo Derivatives of 2-Phenyl-5-oxazolone

Ahmad S. Shawali, Abdou O. Abdelhamid, Nada F. Ahmad, and Cyril Párkányi

*Department of Chemistry, Faculty of Science, University of Cairo, Giza, Egypt

Abstract

Spectroscopic methods (1H NMR and IR) were used to determine the structure of the 4-arylazo derivatives of 2-phenyl-5-oxazolone. The data indicate that such compounds exist in the chelated hydrazone form 1A(z). The 15N isotopomer of compound 1a confirms the hydrazone structure. Also, the HMO method has been used to study tautomerism in such compounds. The results are in full agreement with the spectral data, the hydrazone form 1A(z) being most stable. It is further shown that both the intermolecular and intramolecular hydrogen bonding and electron-withdrawing substituents favor the hydrazone tautomer.

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Report | Regular issue | Vol 19, No. 12, 1982, pp.2339-2343
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DOI: 10.3987/R-1982-12-2339
Selective Preparation. 39. Preparation of Some Chlorodibenzofurans from 1-Hydroxy- and 2-Hydroxydibenzofuran

Masashi Tashiro and Haruo Yoshiya

*Research Institute of Industrial Science, Faculty of Engineering, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan

Abstract

Some chlorodibenzofurans such as 1-chloro-, 2-chloro-, 1,2,4-trichloro- and 1,2,3-trichlorodibenzofurans were prepared from 1-hydroxy- and 2-hydroxydibenzofuran.

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Report | Regular issue | Vol 19, No. 12, 1982, pp.2345-2347
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DOI: 10.3987/R-1982-12-2345
Preparative Electrochemistry I. A Novel Electrochemical Oxodation of a 1,2,3,4-Tetrahydrocarbazole to a Carbazole Derivative

Gilbert Reymond, Janis Vasilevskis, and Voldemar Toome

*Roche Research Center, Hoffman-La Roghe Inc., Nutley, New Jersey 07110, U.S.A.

Abstract

Diethyl(6-chloro-1,2,3,4-tetrahydro-2-carbazolyl)methyl malonate can be oxidized via a four electron process at a platinum electrode in 0.1 M tetraethylammonium p-toluenesulfonate in methylene chloride to diethyl(6-chloro-2-carbazolyl)methyl malonate in 15% yield.

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Report | Regular issue | Vol 19, No. 12, 1982, pp.2349-2354
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DOI: 10.3987/R-1982-12-2349
Deterimination of Structures of Tri- and Tetrabromodibenzofurans Formed in Bromination of Dibenzofuran

Masashi Tashiro and Haruo Yoshiya

*Research Institute of Industrial Science, Faculty of Engineering, Kyushu University, 6-1, Kasuga-koen, Kasuga 816-8580, Japan

Abstract

Dibenzofuran reacted with bromine in the presence of Fe powder to afford tri- and tetrabromodibenzofurans and their structures were determined.

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Report | Regular issue | Vol 19, No. 12, 1982, pp.2355-2360
Published online:
DOI: 10.3987/R-1982-12-2355
Sindamine, Punjabine, and Gilgitine: Three New Secobisbenzylisoquinoline Alkaloids

John E. Leet, S. Fazal Hussain, Robert D. Minard, and Maurice Shamma

*Department of Chemistry, The Pennsylvania State University, York Campus, P1031 Edgecomb Avenue, York, Pennsylvania 17403, U.S.A.

Abstract

Three new secobisbenzylisoquinolines found in Berberis lycium Royle (Berberidaceae) are (+)-sindamine (3). (—)-punjabine (4) and (—)-gilgitine (5). Alkaloids 4 and 5 are the first seco dimeric alkaloids derived from in vivo oxidation of a bisbenzylisoquinoline precursor incorporating three diaryl ether bridges.

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23 data found. 1 - 23 listed