Regular Issue

Vol. 32, No. 3, 1991

14 data found. 1 - 14 listed
Communication | Regular issue | Vol 32, No. 3, 1991, pp. 425 - 430
Published online:
DOI: 10.3987/COM-90-5635
1,3,2-Biphenyldioxaborepin (2,2’-Biphenoxyborane) as a New Hydroborating Agent. Directive Effects in the Hydroboration of the Alkenes and Alkynes

Jin Soon Cha,* Jeong Beob Seo, Jae Cheol Lee, Jong Mi Kim, Hyung Soo Lee, Young Bae Park, Jae Kook Uhm, Sang Chul Shim, Hong Seok Kim, Tae Jeong Kim, Young Woo Kwak, and Dong Ho Lee

*Department of Chemistry, Yeungnam University, Kyongsan 712-749, Korea


2,2’-Biphenoxyborane (1,3,2-biphenyldioxaborepin, 1), readily available from the reaction of 2,2’-biphenol with borane in THF, reacts with alkenes readily at 25 °C, or rapidly at 68 °C, and with alkynes rapidly at 25 °C, to give the corresponding alkyl- and alkenylbiphenoxyboranes in high yields. These hydroboration reactions proceed stereospecifically in a cis manner. A similar regioselectivity to catecholborane is realized with a greater reactivity.

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Communication | Regular issue | Vol 32, No. 3, 1991, pp. 431 - 436
Published online:
DOI: 10.3987/COM-90-5656
Synthetic Studies on Aplysiatoxin. Intramolecular Ester Formation from 3-Acetoxyfuran Derivative via Oxidative Ring Opening Reaction

Kunisuke Okada,* Masanori Mizuno, Hidetsugu Sasaki, Kenji Sugiura, Hideo Tanino, Hisae Kakoi, and Shoji Inoue

*Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tenpaku, Nagoya 468-8503, Japan


Two steps synthesis of 3-acetoxyfuran derivative (4) from acetylene derivative (3) and the conversion 4 to (3R,4R)-3,4-dihydroxypentanoic acid derivative (5) are described.

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Communication | Regular issue | Vol 32, No. 3, 1991, pp. 437 - 442
Published online:
DOI: 10.3987/COM-91-5663
Structural Determination of the Ozonides Derived from Mono-substituted Alkenes

Yung-Son Hon,* Ling Lu, Rong-Chi Chang, and Kuan-Po Chu

*Institutue of Chemistry, Academia Sinica, 128, Yan-Chiu-Yuan Road, Sec II, Nankang, Taipei,11529, Taiwan, R.O.C.


The structures of 1,2,4-trioxolanes (ozonides) (2a-2f) derived from mono-substituted alkenes (1a-1f), respectively, were determined by spectroscopic methods, such as 1H-nmr, 13C-nmr, ir, two-dimensional nmr, and mass spectra. The coupling constant of the geminal protones on the trioxolane ring is zero. This unusual coupling constant resulted from the electronegatively of two oxygen atoms near the geminal protons.

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Communication | Regular issue | Vol 32, No. 3, 1991, pp. 443 - 448
Published online:
DOI: 10.3987/COM-91-5667
Simple Synthesis of 1,3,4,5-Tetrahydropyrrolo[4,3,2-de]quinoline and 5-Hydroxy-4-nitroindole (Synthetic Study for Indoles Having a Nitrogen Containing Functional Group at the 4-Position)

Shin Hamabuchi, Hirokazu Hamada, Akiko Hironaka, and Masanori Somei*

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


A simple four (or three) step synthesis method for 1,3,4,5-tetrahydropyrrolo[4,3,2-de]quinoline (6) from indole-3-carboxaldehyde (9) is developed. A single step preparation of 5-hydroxy-4-nitroindole (8) by the oxidation of 4-aminoindole (16) is also reported.

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 449 - 458
Published online:
DOI: 10.3987/COM-90-5543
Synthesis of and Nucleophilic Addition Reactions to an 8-Ethenyl-1,2,4-triazolo[4,3-a]pyrazine Derivative

Robert H. Bradbury*

*Department of Chemistry, ICI Pharmaceuticals, Mereside, Alderley Park, Macclesfield, Cheshire, SK10 4TG, U.K.


Synthesis of and nucleophilic addition reactions to N-[(1S,2S)-1,3-dicyclohexyl-1-hydroxy-2-propyl]-8-ethenyl-6-phenyl-1,2,4-triazolo[4,3-a]pyrazine-3-acetamide are described.

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 459 - 467
Published online:
DOI: 10.3987/COM-90-5561
Preparation of Substituted, Annulated Benzimidazoles via Benzyne Mediated Cyclization

Joan M. Caroon* and Lawrence E. Fisher

*Institute of Organic Chemistry, Syntex Research, Palo Alto, California 94304, U.S.A.


The synthesis of 1,2-annulated benzimidazoles via an internal benzyne cyclization is described.

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 469 - 476
Published online:
DOI: 10.3987/COM-90-5601
Synthesis and Stereochemical Study of (±)-(2R*, 11bS*)-9,10-Dimethoxy-1,3,4,6,7,11b-hexahydrospiro[benzo[a]quinolizine-2,5’-oxazolidine]-2’,4’-dione

J. Carlos Menéndez, Mercedes Villacampa, and Mónica M. Söllhuber*

*Departamento de Química Orgánica y Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain


The synthesis of (±)-(2R*, 11bS*)-9,10-dimethoxy-1,3,4,6,7,11b-hexahydrospiro[benzo[a]quinolizine-2,5’-oxazolidine]-2’,4’-dione (1) was achieved by two alternative route, involving the cyclization of α-hydroxy amide (5) with ethyl carbonate in the presence of sodium hydride or treatment of cyanohydrin (3) with chlorosulfonyl isocyanate followed by acid hydrolysis. The stereochemistry of 1 was established on the basis of a spectroscopic study of its precursor (6).

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 477 - 480
Published online:
DOI: 10.3987/COM-90-5646
Alkali Metal Fluoride Promoted Generation of Nitrile Oxides from Hydroximoyl Chlorides

Jae Nyoung Kim, Kun Hoe Chung, and Eung K. Ryu*

*Division of Organic Chemistry, Korea Research Institute of Chemical Technology, P.O.Box 9, Daedeog Danji, Daejoen 305-606, Korea


Some nitrile oxides were generated from hydroximoyl chlorides by alkali metal fluoride in the presence of methyl acrylate to give isoxazoline derivatives 2 in high yields.

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 481 - 488
Published online:
DOI: 10.3987/COM-90-5654
A Convenient New Synthesis of 17-Azasteroids. Preparation of Some Novel N-Chloro-17-aza- and N-Chloro-17a-aza-17a-homosteroids as Potential Affinity Labels and Enzyme Inhibitors

Thomas G. Back,* Enoch K. Y. Lai, and Jacek W. Morzycki

*Department of Chemistry, University of Calgary, Calgary, Alberta, T2N 1N4, Canada


An efficient new synthesis of 17-azasteroids in the estrane and androstane series was developed from readily available 16,17-seco 17-carboxylic acid precursors by means of a diphenylphosphoryl azide-mediated Curtius rearrangement as the key step. Several novel N-chloro-17-aza- and N-chloro-17a-aza-17a-homosteroids were prepared from the corresponding lactams with N-chlorosuccinimide.

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 489 - 497
Published online:
DOI: 10.3987/COM-90-5659
Easy Preparation of Indoloquinolizidine Enamides

Mauri Lounasmaa* and Esko Karvinen

*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, P.O. Box 6100, FIN-02150 HUT, Espoo 15, Finland


A new and efficient synthesis of indoloquinolizidine enamines, including the highly valuable Wenkert’s enamine (9a), is described. The behaviour of enamines (9a) and (9b) under reductive conditions was investigated.

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 499 - 510
Published online:
DOI: 10.3987/COM-91-5661
Revised Structures of Albanins D and E, Geranylated Flavones from Morus alba

Toshio Fukai and Taro Nomura*

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


The chemical shifts of the proton signals of the hydrogen-bonded hydroxyl groups of albanins D and E, isolated from Morus alba L. (Moraceae), were compared with those of the hydroxyl groups of 6- or 8-isoprenoid substituted flavones to doubt the location of the geranyl groups of albanins D and E. The proposed structures (3) and (4) for albanins D and E were revised to the structures (1) and (2), respectively, on the basis of the syntheses of 6-geranylated flavones (1 and 2) and 8-geranylated flavones (3 and 4).

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 511 - 520
Published online:
DOI: 10.3987/COM-91-5668
Sodium Dithionite Reduction of 1-[2-(3-Indolyl)ethyl]pyridinium Salts: Formation of a 1,2-Dihydropyridine Derivative via the Corresponding 1,4-Dihydropyridine Derivative

Reija Jokela, Jari Miettinen, and Mauri Lounasmaa*

*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, P.O. Box 6100, FIN-02150 HUT, Espoo 15, Finland


The 1,2-dihydropyridine derivative (3) was prepared by the sodium dithionite reduction of 1-[2-(3-indolyl)ethyl]pyridinium bromide (2). It is shown that the isolated 1,2-dihydropyridine derivative (3) is a rearrangement product of the initially formed unstable 1,4-dihydropyridine derivative (4).

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Paper | Regular issue | Vol 32, No. 3, 1991, pp. 521 - 528
Published online:
DOI: 10.3987/COM-91-5669
Synthesis of (—)-Galantinic Acid from D-Ribonolactone

Nobuo Ikota*

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


The synthesis of the revised structure of (—)-galantinic acid was achieved from D-ribonolactone.

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Review | Regular issue | Vol 32, No. 3, 1991, pp. 529 - 597
Published online:
DOI: 10.3987/REV-90-422
Meldrum’s Acid in Orgnaic Synthesis

Bang-Chi Chen*

*Department of Chemistry, Drexel University, Philadelphia, Pennsylvania 19104, U.S.A.


The synthesis and reactions of Meldrum’s acid derivatives as well as their applications in natural product syntheses reported during 1978-1990 are reviewed.

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14 data found. 1 - 14 listed