Regular Issue

Vol. 16, No. 12, 1981

17 data found. 1 - 17 listed
Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2085 - 2090
Published online:
DOI: 10.3987/R-1981-12-2085
Diels-Alder Type Reactions of 2-Phenyl-1-azaspiro[2.2]pent-1-ene

Otohiko Tsuge,* Toshiyuki Ohnishi, and Hiroyuki Watanabe

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


Highly strained 2-phenyl-1-azaspiro[2.2]pent-1-ene reacted with cyclopentadienones to give the corresponding 2H-azepine-2-spiro-cyclopropanes directly, with loss of carbon monoxide. However, the reaction of the azaspiropentene with 1,3-diphenylisobenzofuran afforded the exo-Diels-Alder adduct. The azaspiropentene reacted with thiobenzoyl isocyanates to give 3-aryl-5-oxo-2,4,6-thiadiazabicyclo[5.2.0]nona-3,6-dienes arising from the rearrangement of initial [4 + 2] cycloadducts.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2091 - 2104
Published online:
DOI: 10.3987/R-1981-12-2091
Total Synthesis of p-Menthenolides

Balkrishna S. Bal and Harold W. Pinnick*

*Department of Chemsitry, The University of Georgia, Athens, Georgia 30602, U.S.A.


A general approach to both cis- and trans-fused α-methylene γ-butyrolactones has been developed. This includes a new, mild method for the oxidation of α,β-unsaturated aldehydes. In addition, a new method to couple trans-α-methylene hydroxy acids into trans-lactones or, alternatively, cis-lactones has been developed. This strategy has been applied to the total synthesis of both cis- and trans-p-menthenolide, prepared in 35% (trans) and 21% (cis) overall yields from isopulegol.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2105 - 2108
Published online:
DOI: 10.3987/R-1981-12-2105
The Biogenesis of Cissampareine and of Micranthiene-type Alkaloids

I. Ralph C. Bick*

*Department of Chemistry, University of Tasmania, GPO Box 252C Hobart, Tasmania, 7001, Australia


A possible mode of biosynthesis is proposed for cissampareine and for the micranthine type of bisbenzylisoquinoline alkaloids.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2109 - 2114
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DOI: 10.3987/R-1981-12-2109
Stereoselective Reduction of 1,2,3,4,6,7,12,12b-Octahydroindolo[2,3-a]quinolizine with Sodium Borohydride in Trifluoeoacetic Acid

Gordon W. Gribble,* Jerry L. Johnson, and Mark G. Saulnier

*Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03775, U.S.A.


The sodium borohydride/trifluoroacetic acid reduction of the title alkaloid (1) is highly stereoselective, giving the all-cis product 2 in excellent yield.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2115 - 2119
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DOI: 10.3987/R-1981-12-2115
Reaction of o-Ethoxalylaminonitriles with Cyanomethylene Compounds in the Presence of Cyanide Ion

Yukihiko Tomioka and Motoyoshi Yamazaki*

*Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan


When 2-ethoxalylaminonaphthalene-1-carbonitrile (I) was treated with potassium cyanide and some cyanomethylene compounds, such as ethyl and methyl cyanoacetates, α-cyanoacetamide and 1-cyanoacetylpyrrolidine, the corresponding 1-aminobenzo[f]quinazolines (IVa - IVd) were obtained.
Similarly, 6-ethoxalylaminoquinoline-5-carbonitrile (II) and 2-ethoxalylaminobenzonitrile (III) gave the corresponding 1-aminopyrido[3,2-f]quinazolines (Va - Vd) and 4-aminoquinazolines (VIa - VId), respectively.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2121 - 2124
Published online:
DOI: 10.3987/R-1981-12-2121
Chemiluminescence of 10-Methylacridinium Salts Following Base Catalysed Oxygenation in Dimethyl Sulfoxide

Nobutaka Suzuki,* Yoshihiko Kazui, Masahiro Kato, and Yasuji Izawa

*Faculty of Engineering, Mie University, 1515 Uehama-cho, Tsu, Mie 514-5807, Japan


When oxidized with ground state oxygen in the presence of t-BuOK in DMSO, 10-methylacridinium methosulfates (1a) gave strong light emission owing to the fluorescence of 10-methylacridone (2) excited to the S1 state.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2125 - 2131
Published online:
DOI: 10.3987/R-1981-12-2125
Chemistry of 1,6-Diazaphenalene. Halogenation

Shieu-Jeing Lee and James M. Cook*

*Department of Chemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, U.S.A.


The reaction of neutral species, 1,6-diazaphenalene, with halogen provided principally 2,3-dihalo- and 2,3,4-trihalodizaphenalenes in addition to lesser quantities of other isomers, whereas, halogenation of the protonated form 1b of 1,6-diazaphenalene gave a 7-substituted diazaphenalene as the major product.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2133 - 2136
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DOI: 10.3987/R-1981-12-2133
1,6-Dihydro-3(2H)-pyridinones as Synthetic Intermediates. Protochemical [2+2]Cycloaddition with Vinyl Acetate

Takeshi Imanishi, Yasuaki Wada, Makoto Inoue, and Miyoji Hanaoka*

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


Photochemical [2+2] cycloaddition of 1,6-dihydro-3(2H)-pyridinones (1a and 1b) with vinyl acetate gave the cycloadducts (2a and 2b). Utilizing this reaction as a key step, 1b was converted into the 4-substituted 1,6-dihydro-3(2H)-pyridinone (3) and the 4-substituted 3-piperidinone (4).

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2137 - 2140
Published online:
DOI: 10.3987/R-1981-12-2137
A Novel Synthesis of Theophyline Derivatives

Fumio Yoneda* and Ryosuke Koga

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


Treatment of 6-amino-5-arylazo-1,3-dimethyluracils with ethyl propiolate gave the corresponding Michael-type adducts, 6-ethoxycarbonylvinylaminouracils, which on treatment with a mixture of hydrochloric acid and acetic acid gave rise to 8-anilinomethyltheophylline derivatives.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2141 - 2148
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DOI: 10.3987/R-1981-12-2141
Structure of Sanggenon C, a Natural Hypotensive Diels-Alder Adduct from Chinese Crude Drug “Sang-bái-pí” (Morus Root Bark)

Taro Nomura,* Toshio Fukai, Yoshio Hano, and Jun Uzawa

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


From the methanol extract of the Chinese crude drug “sang-Bái-Pí” (Japanese name Sohakuhi), the root barks of Morus sp. (Moraceae), a new flavanone derivative with a fused dihydrochalcone partial moiety was isolated and named sanggenon C. The structure was shown to be I on the basis of chemical and spectral data. Sanggenon C (I) is regarded biogenetically as a Diels-Alder adduct of a chalcone derivative and a dehydroprenylflavanone derivative. Intravenous injection of I (1 mg/Kg) produced a significant hypotension in rabbit.

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Communication | Regular issue | Vol 16, No. 12, 1981, pp. 2149 - 2154
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DOI: 10.3987/R-1981-12-2149
Reactions of 4-Ethoxyalkylidene-2-phenyl-2-oxazolin-5-ones with 1,3-Binucleophilic Heteroaromatic Systems

Otohiko Tsuge* and Michihiko Noguchi

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


One-pot syntheses of pyrido[1,2-b]pyrimidine and thiazolo[2,3-b]pyrimidine derivatives were achieved by the reactions of 4-ethoxyalkylidene-2-phenyl-2-oxazolin-5-ones with 2-aminopyridines and 2-aminothiazole in refluxing ethanol, respectively. In the reaction of the oxazolinone with 2-aminopyrimidine under similar conditions, however, the expected pyrimidopyrimidine derivative was not formed, but instead (2-pyrimidylaminomethylene)-oxazolinone and its ethanolysis product were obtained.

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Report | Regular issue | Vol 16, No. 12, 1981, pp. 2155 - 2157
Published online:
DOI: 10.3987/R-1981-12-2155
A Convenient Synthesis of Acetylchromans

Vinod Kumar Ahluwalia,* Krishan Kumar Arora, and Ravinder Singh Jolly

*Department of Chemistry, University of Delhi, Delhi-110 007, India


A convenient one-step synthesis of acetylsubstituted 2,2-dimethylchromans involving the condensation of polyhydroxyacetophenones with 2-methylbut-3-ene-2-ol in presence of orthophosphoric acid is described.

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Report | Regular issue | Vol 16, No. 12, 1981, pp. 2159 - 2167
Published online:
DOI: 10.3987/R-1981-12-2159
Synthesis and NMR Study of Mannich Bases of 8-Acetoxy-indolizines

Henri Sliwa* and Dominique Blondeau

*Laboratoire de Chimie Organique et Environnement, Université des Sciences et Technologies de Lille, Bat. C4 -2eme Etage, 59655 Villeneuve d’ Ascq Cedex, France


Crystallized hydrochlorides of some unstable Mannich bases derived from 8-acetoxyindolizine (1) and 3-acetyl-8-acetoxyindolizine (3) have been prepared by condensation of iminium salts on these substrates. The nmr study of the free bases and their hydrochlorides shows the selectivity of the reaction which introduces the aminomethyl side chain at positions 3 in 1 and 1 in 3. The disappearance of the strong deshielding observed for H-5, in the 3-acetyl series, when one passes from the free base to the corresponding hydrochloride is discussed in terms of restricted rotation and dipolar interactions.

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Report | Regular issue | Vol 16, No. 12, 1981, pp. 2169 - 2171
Published online:
DOI: 10.3987/R-1981-12-2169
New Steroidal Heterocycles. Part XII. A Synthesis of 1,6-Bisthiabenz[3,4]-D-homoestra-3,5(10),8,14-tetraen-17a-one

Sukuru Raghu Ramadas* and Mokkapati Vijaya Krishna

*Department of Chemistry, Indian Institute of Technology, Madras, 600 036, India


The synthesis of the title compound (I) from isothiochroman-4-one (II) is reported.

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Report | Regular issue | Vol 16, No. 12, 1981, pp. 2173 - 2176
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DOI: 10.3987/R-1981-12-2173
A New Method for the Preparation of Substituted 2-Pyrimidinyl- and s-Triazinyl-formamide Oximes. Formylation of Heterocyclic Amines with Trisformaminomethane

Branko Stanovnik,* Janko Zmitek, and Miha Tisler

*Department of Chemistry, E. Kardelj University, Murnikova 6, 61000 Ljubljana, Yugoslavia


A novel method for the preparation of substituted 2-pyrimidinyl- and s-triazinyl-formamide oximes is described. Heterocyclic amines 1 are first converted with trisformaminomethane, as the most powerful formylating agent, into formylamino derivatives 3. These give by treatment with hydroxylamine the corresponding formamide oximes 4 in yields up to 95%.

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Report | Regular issue | Vol 16, No. 12, 1981, pp. 2177 - 2180
Published online:
DOI: 10.3987/R-1981-12-2177
Activated Nitriles in Heterocyclic Synthesis: A Novel Synthesis of Pyrano[2,3-c]pyrazoles

Sadek Abdou, Sherif Mahmoud Fahmy, Kamal Usef Sadek, and Mohamed Hilmy Elnagdi*

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


A novel synthesis of pyrano[2,3-c]pyrazoles is reported via reaction of β-phenylacrylonitrile with 3-methyl-2-pyrazolin-5-ones.

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Review | Regular issue | Vol 16, No. 12, 1981, pp. 2181 - 2236
Published online:
DOI: 10.3987/R-1981-12-2181
13C NMR Spectroscopy of Flavonoids

Pawan Kumar Agrawal and Ram Prakash Rastogi*

*Central Drug Research Institute, Lucknow 226001, India


A survey of 13C NMR spectroscopy data of the various classes of flavonoids is presented which shows that the carbon resonances of ring C are useful in identification of the basic skeletal type. The applications of this data in structure elucidation studies such as determination of the positions of alkylation, acylation, glycosylation etc. are reviewed.

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17 data found. 1 - 17 listed