Special Issue

Teruaki Mukaiyama's Special Issues, Vol. 52, No. 3, 2000

45 data found. 31 - 45 listedFirst Previous
Paper | Special issue | Vol 52, No. 3, 2000, pp. 1261 - 1278
Published online:
DOI: 10.3987/COM-99-S140
Synthesis and Reaction of Chiral 4,5-Disubstituted 2-Oxazolidinones from 3-Ethoxy-6-(N-alkyl-N-tert-butoxycarbonyl)aminohexa-2,4-dienoates in the Presence of Concentrated Sulfuric Acid Supported on Silica Gel

Tomikazu Kawano, Kenji Negoro, Hajime Nitta, and Ikuo Ueda*

*The Institute of Scientific and Industrial Research, Osaka University, Mihogaoka, Ibaraki, Osaka 567-0047, Japan

Abstract

Reaction of chiral 3-ethoxy-6-(N-alkyl-N-tert-butoxycarbonyl)-aniino-hexa-2,4-dienoates (3) and related compounds with 97% concentrated sulfuric acid supported on silica gel proceeded stereo- and regio-selectively to yield chiral 4,5-disubstituted N-alkyl-2-oxazolidinones (7). Under the limited conditions, 7 were converted into N-alkyl-2-pyrrolylacetates (8) and 2-oxazolidinone derivatives (12) which may serve as a chiral auxiliary.

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Paper | Special issue | Vol 52, No. 3, 2000, pp. 1279 - 1295
Published online:
DOI: 10.3987/COM-99-S141
A Facile Synthesis of 5-Substituted 2-Furyl-, 2-Thienyl- and 2-Pyrrolylacetates by Cyclodehydration of γ-Functionalized α,β-Unsaturated Ketones

Tomikazu Kawano, Toru Ogawa, Saiful Md. Islam, and Ikuo Ueda*

*The Institute of Scientific and Industrial Research, Osaka University, 8-1. Mihogaoka, Ibaraki, Osaka 567-0047, Japan

Abstract

Synthesis of 5-substituted 2-furyl-, 2-thienyl- and 2-pyrrolyl-acetates is achieved by acid-catalyzed cyclodehydration of γ-hydroxy (γ-acetylthio and γ-amino)-α,β-unsaturated ketones generated from ethyl 6-substituted 3-ethoxy-6-hydroxy-(6-acetylthio and 6-amino)hexa-2,4-dienoates which are easily accessible from α-functionalized carbonyl compounds and Wittig reagents.

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Paper | Special issue | Vol 52, No. 3, 2000, pp. 1297 - 1314
Published online:
DOI: 10.3987/COM-99-S142
Investigations Directed at the Total Synthesis of Ouabain. Lessons Learned fromDegradation Studies

Larry E. Overman* and Paul V. Rucker

*516 Rowland Hall, University of California, Irvine, California 92697-2025, U.S.A.

Abstract

A procedure has been developed for transforming pentacyclic Heck product (8) to enone (10), an intermediate having appropriate functionality for future elaboration of the Cl and C3 diol functionality of ouabagenin. The plant-derived cardiac glycoside ouabain has been degraded to analogs (17) and (20) that contain, respectively, a Δ9,11 double bond and C17 nitrile. These intermediates should be useful in future efforts to develop chemistry for functionalizing the Δ9,11 double bond of 8 to incorporate Cli oxidation and for elaborating the β C17 nitrile of this advanced synthetic intermediate to a β butenolide.

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Paper | Special issue | Vol 52, No. 3, 2000, pp. 1315 - 1328
Published online:
DOI: 10.3987/COM-99-S143
A Highly Efficient Synthetic Route to (-)-Furaquinocin C

Amos B. Smith, III*, José Pérez Sestelo, and Peter G. Dormer

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

Abstract

The first total synthesis of (-)-furaquinocin C, a member of the furaquinocin family of cytotoxic antibiotics, has been achieved. Central features of the successful synthetic strategy include Diels-Alder construction of the furanonaphthoquinic skeleton and sequential cuprate-mediated conjugate additions to an α,β-unsaturated lactone. The synthetic route proved remarkably efficient requiring only six steps from (R)-(+)-angelicalactone, and utilizing a mere four reaction vessels. This stereospecific construction of (-)-furaquinocin C confirms earlier assignments of absolute and relative stereochemistry for the furaquinocins and also constitutes completion of a formal synthesis of (-)-furaquinocin F.

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Paper | Special issue | Vol 52, No. 3, 2000, pp. 1329 - 1336
Published online:
DOI: 10.3987/COM-99-S144
Reactivity of 2',3'-Anhydro Pyrimidine Nucleosides toward Trimethylaluminum

Kosaku Hirota,* Hideki Takasu, and Hironao Sajiki

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

Abstract

Treatment of 2’,3’-anhydro pyrimidine nucleoside derivatives (1) with trimethylaluminum afforded 1-(3-deoxy-3-methyl-β-D-arabinofuranosyl)pyrimidine derivatives (2) and 1-(2-deoxy-2-methyl-β-D-xylofuranosyl)pyrimidine derivatives (3) as a mixture in approximately 2 : 1 - 3 : 1 ratio via ring-opening of the epoxide involving the nucleophilic attack of trimethylaluminum at the 3’ or 2’-position of 1.

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Paper | Special issue | Vol 52, No. 3, 2000, pp. 1337 - 1344
Published online:
DOI: 10.3987/COM-99-S145
Stereoselective Aldol Addition of a Chiral Glycine Enolate Synthon to Heteroaromatic Aldehydes

Piero Dalla Croce,* Raffaella Ferraccioli, Concetta La Rosa, and Enrica Pizzatti

*Dipartimento di Chimica Organica e Industriale, Centro C. N. R., V. Venezian 21 I-20133 Milano, Italy

Abstract

The stereocontrolled addition of (2S)-(+)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine (1) to heterocyclic aldehydes (2) gives mainly a mixture of syn/anti isomers (3) and (4) whose steric configuration was assigned on the basis of spectroscopic data and accepted model for aldol condensation of 1. The possible conversion of adducts to threo β-substituted heteroaromatic serines is demonstrated.

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Paper | Special issue | Vol 52, No. 3, 2000, pp. 1345 - 1352
Published online:
DOI: 10.3987/COM-99-S146
The Structure and Antimalarial Activity of Some 1,2,4-Trioxanes, 1,2,4,5-Tetroxanes, an Bicyclic Endoperoxides. Implications for the Mode of Action

Charles W. Jefford,* Jean-Claude Rossier, and Wilbur K. Milhous

*Department of Organic Chemistry, University of Geneva, 1211 Geneva 4, Switzerland

Abstract

The mode of antimalarial action of cis-fused cyclopenteno-1,2,4-trioxanes (7-13), dispiro-1,2,4,5-tetroxanes (14-17), and bridged bicyclic endoperoxides (18-22) was examined by systematically changing substituents at positions remote from the O-O bond. It is concluded that peroxides of high activity (7-11, 14-15, 18, and 19) are able to intimately dock on heme and rearrange efficiently to an ethyl radical which kills the parasite by alkylation. Dimethyl substituents on the spirocyclohexane ring in the trioxanes (12 and 13) and tetroxane (16) diminish activity by hampering either docking or the reactivity of a C-centered radical. Endoperoxides derived from methylnaphthalenes (20-22) are inactive owing to their inability to generate an ethyl radical.

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Paper | Special issue | Vol 52, No. 3, 2000, pp. 1353 - 1358
Published online:
DOI: 10.3987/COM-99-S147
Preparation of Optically Active 15-Epoxy-α-linolenic Acids and Their Anti-Rice Blast Fungus Activities

Tadahiro Kato,* Toshio Nakai, Takayuki Ishimatu, Masahiro Hoshikawa, and Tsuneo Namai

*Department of Chemistry, Faculty of Science, Science University of Tokyo, Kagurazaka 1-3, Shinjuku-ku, Tokyo 162-8601, Japan

Abstract

By the action of NBS in aq. DME, α-linolenic acid was oxidized to 15-bromo-16-hydroxy-α-linolenic acid in 35% conversion yield. The bromohydrin was treated with lipase-PS and vinyl acetate to give the resolved acetate and bromohydrin. (15S,16R)- and (15R,16S)-Epoxy-α-linolenic acids were prepared from the corresponding resolved products. A comparison of anti-rice blast fungus activities showed that an unnatural epoxide is stronger than the natural epoxide.

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Paper | Special issue | Vol 52, No. 3, 2000, pp. 1359 - 1370
Published online:
DOI: 10.3987/COM-99-S149
Optical Resolution of Fragrant Lactones

Hiroyuki Nohira,* Keiko Mizuguchi, Toru Murata, Yuko Yazaki, Miho Kanazawa, Yoshio Aoki, and Misako Nohira

*Department of Applied Chemistry, Faculty of Engineering, Saitama University, Urawa, Saitama 338-8570, Japan

Abstract

Optical resolution of six chiral fragrant lactones (δ-jasmine lactone, massoia lactone, tuberolactone, pentynyllactone, δ-decalactone, and γ-nonalactone) was investigated by means of either the diastereomeric salt formation method or the diastereomeric amide formation method. Using these procedures, we obtained each enantiomer from five of the six lactones, except for massoia lactone. All five lactones were obtained in a good yield and with high optical purity. Sensoric characteristics on both enantiomers and racemic modification of four lactones are given.

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Note | Special issue | Vol 52, No. 3, 2000, pp. 1371 - 1383
Published online:
DOI: 10.3987/COM-99-S120
Synthesis of Fused Systems in the Isoquinoline Series: Oxazolo- and Pyrrolo[3,2-c]isoquinolines

Jean-François Brière, Georges Dupas,* Guy Quéguiner, and Jean Bourguignon

*Laboratoire de Chimie Organique Fine et Hétérocyclique de L’IRCOF , UPRESA 6014, CNRS, Institut National des Sciences Appliquées de Rouen, BP 08, 76131 Mont Saint Aignan Cedex, France

Abstract

In order to synthesize the pyrrolo[3,2-c]isoquinoline structure, three different routes starting from readily available isoquinolines were tried. The ring closure reaction of a malonic derivative of 4-amino-3-bromoisoquinoline led to an oxazolo[3,2-c]isoquinoline instead of the target molecule. This latter was obtained via Sonagashira coupling reaction followed by ring closure under basic conditions. A study of the lithiation of the N-sulfonated pyrrolo[3,2-c]isoquinoline was undertaken. After optimization of the lithiation conditions, various 2-substituted pyrrolo[3,2-c]isoquinolines were obtained and their oxidation reactions studied.

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Note | Special issue | Vol 52, No. 3, 2000, pp. 1385 - 1391
Published online:
DOI: 10.3987/COM-99-S128
Unexpected Reaction of 3-Phenyl-3-chloro-2-oxopropanoic Acid Derivatives with Sodium Azide. A Novel Synthesis of Highly Functionalized Oxazolines

Vakhid A. Mamedov, Aidar T. Gubaidullin, Igor A. Litvinov, and Sadao Tsuboi*

*Department of Environmental Chemistry and Materials, Okayama University, 2-1-1 Tsushima-naka, Okayama 700-8530, Japan

Abstract

The reaction of 3-phenyl-3-chloro-2-oxopropanoic acid derivatives with sodium azide proceeded unexpectedly with the formation of oxazolines via intermediately forming α-azido- and/or α-imino ketones.

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Note | Special issue | Vol 52, No. 3, 2000, pp. 1393 - 1398
Published online:
DOI: 10.3987/COM-99-S131
Synthesis of 5-Diphenylphosphinoyl-2,3-dihydropyran-4-ones

Tatsuo Okauchi,* Hironobu Nagamori, Ryouji Kouno, Junji Ichikawa, and Toru Minami*

*Department of Applied Chemistry, Faculty of Engineering, Kyushu Institute of Technology, 1-1 Sensuicho, Tobata, Kitakyushu, 804-8550, Japan

Abstract

5-Diphenylphosphinoyl-2,3-dihydropyran-4-ones are readily prepared from the corresponding 5-diphenyiphosphinoyl-1-buten-3-yne under mild acidic conditions. The phosphorus substituted pyrones are converted to more substituted pyrones via 1,4-addition of copper reagents followed by Homer-Wittig reaction.

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Review | Special issue | Vol 52, No. 3, 2000, pp. 1399 - 1409
Published online:
DOI: 10.3987/REV-99-SR5
Stereocontrolled Syntheses of Unsymmetrically Substituted Furofuran Lignans

Hiroshi Ohmizu,* Tsuyoshi Ogiku, and Tameo Iwasaki

*Discovery Research Laboratory, Tanabe Seiyaku Co., Ltd., 3-16-89 Kashima, Yodogawa, Osaka 532-8505, Japan

Abstract

Novel and efficient methods for the syntheses of the simple furofuran lignans (I) and the bislactone furofuran lignans (III) are comprehensively described. Asymmetric synthesis of the series (I) based on the enantioselective Michael addition reaction is also described

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Review | Special issue | Vol 52, No. 3, 2000, pp. 1411 - 1434
Published online:
DOI: 10.3987/REV-99-SR6
Perfluorinated Acyl(aroyl)pyruvates as Building Blocks for the Synthesis of Heterocycles

Viktor I. Saloutin,* Yanina V. Burgart, C. Oliver Kappe, and Oleg N. Chupakhin

*Institute of Organic Synthesis, Urals Division, Russian Academy of Sciences, 20, S. Kovalevskaya st., Ekaterinburg, GSP-147, 620219, Russia

Abstract

Data on the synthesis and chemical transformations of 3-polyfluoroacyl- and 3-pentafluorobenzoylpyruvates and their derivatives are reviewed. Reactions giving fluorinated heterocycles and syntheses based on these transformations are discussed.

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Review | Special issue | Vol 52, No. 3, 2000, pp. 1435 - 1449
Published online:
DOI: 10.3987/REV-99-SR7
Origin of π-Facial Diastereoselection in Carbonyl Addition. Application of the Exterior Frontier Orbital Extension Model to 1,3-Diheteran-5-ones (Heteroatom = O, S)

Shuji Tomoda,* Daisuke Kaneno, and Takatoshi Senju

*Department of Life Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan

Abstract

The exterior frontier orbital extension model (the EFOE Model) strongly suggested that reversal of π-facial diastereoselection in nucleophilic additions of 1,3-diheteran-5-ones (heteroatom = O or S) may originate from the unique groundstate conformation and the π-facial difference in the LUMO extension around the carbonyl carbon rather than from transition state effects. Intrinsic reaction coordinate (IRC) and natural bond orbital (NBO) analyses of transition states of LiAlH4 reduction of these ketones have strongly indicated that the transition state effects (the torsional strain of the ketone moieties and the antipenpianar effects involving the incipient bond proposed by the conventional theoretical models for π-facial diastereoselection ; the Felkin-Anh model and the Cieplak model) are not responsible for facial selection.

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