Special Issue

Shigeru Oae's Special Issues, Vol. 44, No. 1, 1997

59 data found. 31 - 59 listedFirst Previous
Paper | Special issue | Vol 44, No. 1, 1997, pp. 237 - 253
Published online:
DOI: 10.3987/COM-96-S13
Synthesis of Various Substituted Benzo[c]-2,7-naphthyridines and an Approach towards the Skeleton of Meridine. Considerations about the Effect of Copper(II) Oxide

Patrick Björk, Johan Malm, Anna-Britta Hörnfeldt, and Salo Gronowitz*

*Organic Chemistry 1 Chemical Center, University of Lund, P. O. Box 124, S-22100, Lund, Sweden


Derivatives of benzo[c]-2,7-naphthyridines have been prepared in good yields and in one step through the use of the Pd(0)-catalyzed cross couplings of formly- and 4- acetyl-3-pyridyltrimethylstannanes with ortho-bromoacetanilides. Perlolidine, an alkaloids present in perennial rye grass, was readily prepared in a few steps taking advantage of the cross coupling. An approach towards the pentacyclic ring skeleton of meridine has also been made, leading to several new derivatives of benzo[c]-2,7-naphthyridine. All cross couplings are greatly promoted by the addition of stoichiometric amounts of copper(II) oxide and a comparison with the use of other catalytic systems in the Pd(0)-catalyzed cross couplings is made.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 255 - 262
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DOI: 10.3987/COM-96-S14
Formation of Cyclic Oligosulfides by Reaction of Hydrazones with Disulfur Dichloride

Yi-Nan Jin, Akihiko Ishii, Yoshiaki Sugihara, and Juzo Nakayama*

*Department of Chemistry, Faculty of Science, Saitama University, Saitama, Saitama 338-8570, Japan


Reactions of some hydrazones with disulfur dichloride were reinvestigated in the absence of a base with expectation of obtaining dithiirane or thiosulfine derivatives. However, treatment of hydrazones derived from 1-adamantyl phenyl ketone, pivalophenone, and benzophenone with disulfur dichloride gave pentathianes and hexathiepanes along with other products, while di-t-butyl ketone hydrazone gave a novel heterocyclic compound, 1,1-di-t-butyltetrathiolane, though in a low yield.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 263 - 276
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DOI: 10.3987/COM-96-S16
Preparation, Properties, and Oxidation of Novel Bis(1,3-dithiole) Compounds Containing A Di(2-thienyl)methane Unit

Akira Ohta and Yoshiro Yamashita*

*Department of Structural Molecular Science, The Graduate University for Advanced Studies, Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan


Novel bis(1,3-dithiole) compounds (5) and (6) containing a di(2-thienyl)methane unit have been prepared by either a Wittig or a Wittig-Horner reaction. These compounds showed irreversible cyclic voltammetric behavior. Oxidation products of 5 and 6 were strongly dependent on the substituents (R1) on the C6-carbon atoms of the 1,4-dithiafulvenyl groups. In the case of R1 = H (5), intermolecular coupling giving a redox-active oligomer selectively occurred. On the other hand, when R1 was methyl, 6 underwent deprotonation by oxidation to give the corresponding stable dithienylmethyl cations showing intense absorptions in the near-infrared region ( > 900 nm in MeCN).

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 277 - 287
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DOI: 10.3987/COM-96-S18
Synthesis and Cytotoxicity of 5-Carbo Analogues of Acetomycin

Jun'ichi Uenishi, Naoko Kobayashi, Osamu Yonemitsu,* Takuma Sasaki, and Yuji Yamada

*Department of Chemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan


Six carbo analogues of anti-cancer antibiotic, acetomycin (1) are synthesized. (±)-(3S*,4S*,5R*)-Dihydro-3-acetyl-5-iodomethyl-3,4-dimethyl-2(3H-furanone (3α), (±)-(3S*,4S*,5S*)-dihydro-3-acetyl-3,4,5-trimethyl-2(3H)-furanone (4α), (±)-(3S*,4S*,5R*)-dihydro-3-acetyt-3,4-dimethyl-5-(phenylthio)methyl-2(3H-furanone (5α), and their diastereoisomers at C-5, 3β, 4β, and 5β are derived from the same intermediate, (±)-(2S*,3R*)-2-(4-methoxybenzyl)oxymethyl-2,3-dimethyl-4-pentenoic acid (7) in 5 and 6 steps, respectively. The carbo analogues exhibit perfect resistance in hydrolysis against pig liver esterase. Among them, β-isomers at C-5 indicate more potent inhibition than α-isomers against three tumor cell lines.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 289 - 304
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DOI: 10.3987/COM-96-S19
Diastereoselective 1,3-Dipolar Cycloaddition of 2-(α,β-Unsaturated) Acyl-3-phenyl-l-menthopyrazoles

Choji Kashima*, Katsumi Takahashi, Iwao Fukuchi, and Kiyoshi Fukusaka

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


The 1,3-dipolar cycloadducts of N-(α,β-unsaturated) acylpyrazoles (2) with benzonitrile oxide or nitrones were afforded in good yield. In the cases of nitrones, the addition of MgBr2 or ZnBr2 promoted the stereoselectivity as well as the acceleration of the reaction rate. In the reaction of 2f and 2g, the big jump on the diastereoselectivity was accomplished by the addition of MgBr2, and (3’S,4’R,5’S)-8 was obtained as optically pure form in over 90% yield. These isoxazolidinecarbonylpyrazoles were converted into azetidinones in moderate yield with the retention of their stereo structures.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 305 - 318
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DOI: 10.3987/COM-96-S20
Synthesis of Taxoids I. Regioselective Lewis Acid-mediated Ring-opening of Aryl Orthoacetates

Naoyuki Harada, Tomiki Hashiyama,* Kunihiko Ozaki, Tetsuo Yamaguchi, Akira Ando, and Kenji Tsujihara

*Lead Optimization Research Laboratory, Tanabe Seiyaku Co.Ltd., 2-2-50, Kawagishi, Toddda, Saitama 335-8505, Japan


The reaction of aryl orthoacetates with acetyl bromide readily proceeded regioselectively to afford the desirable aryl bromides in the presence of tin(II) or zinc bromide as a catalyst. The synthesis of some docetaxel derivaives is also described by using this improved process.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 319 - 324
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DOI: 10.3987/COM-96-S22
Synthesis of Optically Pure β-Phenylselenoalanine Through Serine-β-lactone: A Useful Precursor of Dehydroalanine

Mitsuru Sakai, Kimiko Hashimoto, and Haruhisa Shirahama*

*School of Science, Kwansei Gakuin University, 1-1-155 Uegahara, Nishinomiya 662-8501, Japan


Optically pure L- and D-β-phenylselenoalanines (PhSeAla), useful precursors of dehydroalanine, were synthesized from L- and D-serine-β-lactone. Elimination reactions of the phenylseleno group to form the dehydroalanine were examined.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 325 - 339
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DOI: 10.3987/COM-96-S23
Optically Pure Alkoxychlorosulfuranes. Synthesis and Transformation to Chiral Sulfoxides, N-p-Tosylsulfilimines, and Sulfonium Ylides

Jian Zhang, Tamiko Takahashi, and Toru Koizumi*

*Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama, Toyama 930-0194, Japan


Optically pure alkoxychlorosulfuranes (1) have been prepared by using the 2-exo-hydroxy-10-bornyl group as a chiral ligand. The structure of sulfurane (1a) was confirmed by 1H-nmr, 13C-nmr, and mass spectra Nucleophilic reaction of 1 with water and NaNHTs proceeded with retention of configuration to give optically pure sulfoxides (2) and N-p-tosylsulfilimines (3), respectively. Sulfonium ylides (4) were obtained as mixtures of diastereomers by the reaction of 1 with NaCH(CO2Me)2. The absolute configuration of sulfilimime (3c) was determined by X-ray analysis.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 341 - 348
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DOI: 10.3987/COM-96-S24
Photoinduced Molecular Transformations. Part 160. Furan Annelation of 2-Hydroxynaphthoquinone Involving Photochemical Addition and Radical Fragmentation: Exclusion of the Intermediacy of [2+2] Cycloadduct in a One-Pot Formation of Furanoquinones by the Regioselective 3+2 Photoaddition of Hydroxyquinones with Alkenes

Hisanori Senboku, Yoshinori Kajizuka, Kazuhiro Kobayashi, Masao Tokuda, and Hiroshi Suginome*

*Organic Synthesis Division, Faculty of Engineering, Hokkaido University, Sapporo 060, Japan


2-Acetoxy-1,4-naphthoquinone underwent [2+2] photoaddition to 2-methylpropene, giving a cyclobutanol acetate exclusively. Hydrolysis of the acetate with acid gave the corresponding cyclobutanol, which was stable under the conditions of an alkene-quinone photoaddition; hydrolysis with a base gave a fused 1-indanone derivative. Photolysis of the hypoiodite generated from the cyclobutanol derivative with mercury(II) oxide-iodine in benzene induced a β-scission of the cyclobutanoxyl radical to give a 2,3-dihydronaphtho[2,3-b]furan-4,9-dione and its [1,2-b]furan-4,5-dione isomer.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 349 - 356
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DOI: 10.3987/COM-96-S26
A Facile and Convenient Synthetic Method for Fluorine-containing 1,2-Dihydropyrimidines and Pyrimidines

Etsuji Okada*, Tatsuhiko Kinomura, Hiroshi Takeuchi, and Masaru Hojo

*Department of Chemical Science andd Engineerring, Faculty of Engineering, Kobe University, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan


β,β-Bis(trifluoroacetyl)vinylamine (1) reacted easily with various aliphatic and aromatic aldehydes in the presence of aqueous ammonia under mild conditions to give 5-trifluoroacetyl-4-trifluoromethyl-1,2-dihydropyrimidines (2) in good yields. Dehydrogenation of 2 with DDQ afforded the corresponding pyrimidines (3) in excellent yelds.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 357 - 366
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DOI: 10.3987/COM-96-S28
Structural Analysis of N-(ω-Phenylalkyl)substituted Quinoxalin-2(1H)-ones and -Thiones

Akira Katoh*, Tohru Yoshida, Junko Ohkanda, and Takehiko Nishio

*Department of Industrial Chemistry, Faculty of Engineering, Seikei University, Musashino-shi, Tokyo 180-8633, Japan


Reaction of quinoxalin-2(1H)-one (1) with v-phenylalkyl halides in the presence of bases gave a mixture of N- and O-alkylated products, which were separated by column chromatography. N-Alkylquinoxalin-2(1H)-ones (2a-c) were easily converted into the corresponding thiones (4a-c) by treatment with Lawesson’s reagent. From X-ray crystallographic analysis, it was revealed that the molecular arrangement of N-phenethylquinoxalin-2(1H)-one (2a) was quite different from that of the corresponding thione (4a). Compound (4a) existed in a pair of conformational isomers in the crystalline state, and this was also supported by the solid-state 13c nmr spectral data.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 367 - 378
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DOI: 10.3987/COM-96-S29
cis-Fused Dihydrofurano-1,2,4-trioxanes

Charles W. Jefford,* Shu-juan Jin, Jean-Claude Rossier, Shigeo Kohmoto, and Gérald Bernardinelli

*Department of Organic Chemistry, Laboratory fo Crystallography, University of Geneva, 30, quai Ernest Ansermet, 1211 Geneva 4, Switzerland


The endoperoxide obtained from 2,5-diphenylfuran at -30°C on catalysis with trimethylsilyl trifluoromethanesulfonate condenses with pivalaldehyde, acetone and cyclohexanone to give the corresponding cis-fused dihydrofurano-1,2,4-trioxanes (20,21,22 and 23) respectively in yields not greater than 27%. The reaction of pivalaldehyde with the endoperoxide derived from 1,4-diphenyl-1,3-cyclopentadiene gives the cis and trans-3-tert-butyl substituted cis-fused cyclopenteno-1,2,4-trioxanes (26 and 27) in 75% yield. The structures of 22, 23, 26 and 27 are determined by X-ray.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 379 - 391
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DOI: 10.3987/COM-96-S30
Ethyl α-Amino-β,β-Diethoxypropionate, a Useful Synthon for the Preparation of 3,4-Fused Pyridine-6-carboxylates from Aromatic Aldehydes

Sunil K. Singh, Mouloud Dekhane, Mireille Le Hyaric, Pierre Potier, and Robert H. Dodd*

*Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, Avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France


An efficient synthesis of ethyl α-amino-β,β-diethoxypropionate (1), via a titanium tetrachloride-catalyzed coupling reaction of ethyl nitroacetate and triethyl orthoformate, is described. Condensation of 1 with various aldehydes followed by reduction and titanium tetrachloridepromoted cyclization of the products afforded 3,4-fused pyridine-6-carboxylates belonging to the azaindole, γ-carboline and isoquinoline families of heterocycles.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 393 - 404
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DOI: 10.3987/COM-96-S32
A Silver Salt – Iodine Reagent System for the Deprotection of Monothioacetals and Dithioacetals

Kiyoharu Nishide, Daisaku Nakamura, Kouichi Yokota, Toshio Sumiya, Manabu Node,* Masaru Ueda, and Kaoru Fuji

*Kyoto Pharmaceutical University, Misasagi, Yamashina, Kyoto 607-8414, Japan


A new reagent (silver salt - iodine) system was developed for the deprotection of monothioacetals and dithioacetals. The reactions using this reagent system afforded the parent carbonyl compounds in rnoderale to quantitative yields under mild conditions. These deprotections were also effective in the catalytic amount of this reagent. As an application of this deprotective reagent system, synthesizing optically active α-hydroxyaldehyde using chiial 1,3-oxathiane was demonstrated.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 405 - 415
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DOI: 10.3987/COM-96-S37
Environmentally Benign Chemistry: Microwave-induced Stereocontrolled Synthesis of β-Lactam Synthons

Bimal K. Banik, Maghar S. Manhas, Ernest W. Robb, and Ajay K. Bose*

*McLean Chemical Sciences Center, Stevens Institute of Technology, Castle Point on the Hudson, Hoboken, NJ 07030, U.S.A.


Microwave irradiation in open glass vessels in unmodified commercial microwave ovens has permitted stereoconholled synthesis of useful β-lactam synfhons not withstanding the fact that the nature of specific activation (if any) of organic reactions by microwaves is not yet completely understood.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 417 - 426
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DOI: 10.3987/COM-96-S40
Synthesis and Reactivities of 1,3-Dimethyl-2-(α-hydroxybenzyl)imidazolium and 1,3-Dimethyl-2-(α-hydroxybenzyl)benzimidazolium Iodides

Akira Miyashita,* Akihito Kurachi, Yoshiyuki Matsuoka, Noriko Tanabe, Yumiko Suzuki, Ken-ichi Iwamoto, and Takeo Higashino

*Schol of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan


1,3-DimethyI-2-(α-hydroxybenzyl)benzimidazolium iodide (3a) was synthesized from 1-methylbenzimidazole (10) through two steps involving lithiation and quaternization. Treatment of 3a with 4-chloro-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine (6) afforded 4-benzoyl-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine (15a). 4-Benzoylquinazoline (14a) and 7-benzoyl-3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimidine (16a) were given by reaction of 3a with 4-chloroquinazoline (5) and 7-chloro-3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimidine (7). Treatment of 3a with benzaldehyde (9a) gave benzoin (8a). Similar results were obtained in the reactions of 1,3-dimethyl-2-(α-hydroxybenzyl)imidazolium iodide (4a).

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 427 - 433
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DOI: 10.3987/COM-96-S41
Thiovalidamine Derivatives of manno-and gluco-Type: Remote Activation and Anchimeric Assistance

Yoshisuke Tsuda, * Tomoko Nakamoto, Fumiyuki Kiuchi, and Yukihiko Kameda

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


The oxazolidone (3) derived from validamine (1) was dithiocarbonylated, on treatment with NaH followed by CS2-Mel, to the N,O-dicarbodithioate (6). On treatment with NaH-Mel, this afforded the manno-type thiovalidamine derivative (7) and then the gluco-type thiovalidamine derivative (8) following the pathway shown in Scheme 2: an activation at a C=S group by methylation, transferring this activation to a remote position accompanied with decarboxylation, and cyclization of the neighboring group to the transferred position (C-3).

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 435 - 442
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DOI: 10.3987/COM-96-S42
Synthesis of New Chiral Catalysts, Isoquinuclidinylmethanols, for the Enantioselective Addition of Diethylzinc to Aryl Aldehydes

Hiroto Nakano, Kazuto Iwasa, and Hiroshi Hongo*

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


New chiral ligands, isoquinuclidinylmethanols, were prepared and their catalytic abilities of asymmetric induction were examined in the addition of diethylzinc to aldehydes to furnish secondq alcohols in up to 76% e.e.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 443 - 457
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DOI: 10.3987/COM-96-S43
Novel Synthesis of Heterocycles Using Nickel(0)-catalyzed [2+2+2] Cocyclization: Catalytic Asymmetric Synthesis of Isoindoline and Isoquinoline Derivatives

Yoshihiro Sato, Toyoki Nishimata, and Miwako Mori*

*Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan


A nickel(0)-catalyzed asymmetric [2+2+2] cocyclization has been realized for the first time. That involves conceptually new enantiotopic group selective formation of the nickelacyclopentadiene (18) and produces the isoindoline (26a) (73% ee, 78% conv. yield) and isoquinoliie (27b) (54% ee, 62% yield) having benzylic chiral carbon centers.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 459 - 465
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DOI: 10.3987/COM-96-S45
Convenient One-Pot Synthesis of Sodium Salt of 5-Mercapto-1,2,3-thiadiazole

Katsumasa Harada,* Teruhiko Inoue, and Hiroshi Yoshida

*Ube Research Laboratory, UBE Indusries, Ltd., 1978-5 Kogushi, Ube Yamaguchi 755, Japan


Trichloroacetoaldehyde-p-toluenesulfonyIhydrazone (3) derived from chloral hydrate reacted in situ with polysulfide salt in the range of pH 10~11 to afford the corresponding 5-mercapto-1,2,3-thiadiazole salt(2) in high yield (69.5 %).

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 467 - 478
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DOI: 10.3987/COM-96-S46
Acid-catalyzed Photoreaction of 6-Chloro-1,3-dimethyluracil to p- and m-Xylene: Formation of Novel Photocycloadducts, 6-Methylene-9,11,X-trimethyl-9,11-diazapentacyclo[,3.02,5.04,8]dodecane-10,12-diones and 5-Methylene-9,11,X-trimethyl-9,11-diazapentacyclo[,3.02,6.04,8]dodecane-10,12-diones

Kazue Ohkura, Koh-ichi Seki,* Hajime Hiramatsu, Keiichi Aoe, and Masanao Terashima

*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan


Uv irradiation of 6-chloro-1,3-dimethyluracil in p- and m-xylenes i n the presence of trifluoroacetic acid gave novel photocycloadducts, 6-methylene-9,11,x-trimethyl-9,11-diazapentacyclo[,3.02,5.04,8]dodecane-10,12-diones and 5-methylene-9,11,x-trimethyl-9,11-diazapentacyclo[,3.02,6.04,8]dodecane-10,12-diones, together with tetramethylcyclooctapyrimidine-2,4-diones as the sole regioisomer. The modes of the cycloaddition were discussed.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 479 - 486
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DOI: 10.3987/COM-96-S48
Facile Synthesis of (+)- and (-)-Geissman-Waiss Lactones

Takafumi Kouyama, Hirofumi Matsunaga, Tadao Ishizuka, and Takehisa Kunieda*

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


(+)- and (-)- Geissman-Waiss lactones (1), were prepared from the readily accessible (4R, 5R)- and (4S, 5S)-5-allyl-4-methoxy-2-oxazolidinones [(+)- and (-)-7], respectively, in a highly stereocontrolled manner from the previously reported building block, 3-[(1S)-2-exo-alkoxy-1-apocamphanecarbonyl]-2-oxazolones (4).

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 487 - 507
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DOI: 10.3987/COM-96-S49
Tandem Peterson-Michael Reaction Using α-Silylalkylphosphine Chalcogenides and Horner-Emmons Reaction of in situ Generated α-Carbanions of Its Products

Takayuki Kawashima,* Mio Nakamura, and Naoki Inamoto

*Department of Chemistry, Graduate School of Science, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8567, Japan


Title tandem reaction was achieved by using α-(trimethylsilyl)alkylphosphine chalcogenides and the lithio derivative of 2-hydroxytetrahydropyran. The Homer-Emmons reaction of the tandem products was accomplished to give the corresponding 2-(β-styryl)tetrahydropyran derivatives by in situ generation and trapping of α-lithio derivatives, followed by Warren‘s method of olefination.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 509 - 518
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DOI: 10.3987/COM-96-S51
Synthesis of Thiophene Derivatives Bearing a Silicon Atom

Osamu Hoshino* and Tetsuya Hirayama

*Faculty of Pharmaceutical Sciences, Science University of Tokyo, 12, Ichigaya Funagawara-machi, Shinjuku-ku, Tokyo 162-0826, Japan


Synthesis of thiophene derivatives containing a sillcon atom is described. Silylation of 2-thienylmethyl chloride (12) with trichlorovinylsilane or chloro(chloromethyl)dimethylsilane was accomplished by addition of 12 to a mixture of Mg and the former reagent in THF or by addition of a mixture of 12 and the latter reagent to a mixture of Mg in THF to give dichloro(2-thienylmethyl) vinylsilane (13) or chloromethyl(dimethyl)(2-thienylmethyl)siane (18). The Grignard reagent (19) of 18 reacted with carbon dioxide, dimethyl carbonate or benzaldehyde to produce dimethyl(2-thienylmethyl)silylacetic acid (20), methyl dimethyl(2-thienylmethyl)silylacetate (21) or 2’-[dimethyl(2-thienylmethyl)silyl]-1’-phenylethanol (22).

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 519 - 530
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DOI: 10.3987/COM-96-S52
A New Efficient Synthesis of Nicotianamine and 2'-Deoxymugineic Acid

Takayuki Shioiri,* Naoko Irako, Sachiko Sakakibara, Fumiyoshi Matsuura, and Yasumasa Hamada

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


Nicotianamine and 2’-deoxymugineic acid, phytosiderophores, have been efficiently synthesized, which will be suitable for large scale production of these plant physiologically important compounds. The synthetic method for 2,3”-dideoxy-3”-oxomugineic acid was also investigated.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 531 - 536
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DOI: 10.3987/COM-96-S54
Synthesis of Benzo[a]quinolizines by the Intramolecular Double Michael Reaction under Three Different Conditions

Masataka Ihara, Masami Yamada, Yohei Ishida, Yuji Tokunaga, and Keiichiro Fukumoto*

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


Benzo[a]quinolizines (4A-C) and (5A-C) were synthesized by the intramolecular double Michael reaction of amide esters (3A-C). canied out using three reagent systems; TBDMSOTf-Et3N, TMSI-(TMS)2NH, and Bu2BOTf-(TMS)2NH.

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Paper | Special issue | Vol 44, No. 1, 1997, pp. 537 - 542
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DOI: 10.3987/COM-96-S55
Syntheses of 1-Substituted (SS)-3-p-Tolylsulfinyl-1,4-dihydropyridines, Chiral NADH Model Compounds

Satoshi Obika, Toshihiko Nishiyama, Satoshi Tatematsu, Masahiro Nishimoto, Kazuyuki Miyashita, and Takeshi Imanishi*

*Faculty of Pharmaceutical Science, Osaka University, 1-6 Yamadaoka, Toyonaka, Osaka 560-0043, Japan


(SS)-3-(p-Tolylsulfinyl)-1,4-dihydropyridines with various kinds of substituents on the N-1 position were synthesized from (SS)-1-lithio-3-(p-tolylsulfinyl)-1,4-dihydropyridine, which was generated on reaction of the 1-benzoyl derivative with methyllithium.

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Review | Special issue | Vol 44, No. 1, 1997, pp. 543 - 572
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DOI: 10.3987/REV-96-SR1
Amphidinolides: Unique Macrolides from Marine Dinoflagellates

Masami Ishibashi and Jun'ichi Kobayashi *

*Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan


A series of macrolides, named amphidinolides, have been isolated from the laboratory-cultured marine dinoflagellates Amphidinium sp., which were symbionts of the Okinawan marine flatworm Amphiscolops sp. These macrolides possess unique chemical structures as well as cytotoxic activities. Here we describe our recent results on the isolation, structure elucidation, and biosynthesis of these unique macrolides.

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Review | Special issue | Vol 44, No. 1, 1997, pp. 573 - 592
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DOI: 10.3987/REV-96-SR2
The 7-N-Oxides of Purines Related to Nucleic Acids: Their Chemistry, Synthesis, and Biological Evaluation

Tozo Fujii *, Taisuke Itaya, and Kazuo Ogawa

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


Recent advances in the chemistry, synthesis, and biological evaluation of the 7-N-oxides of purines related to nucleic acids are reviewed. The 7-N-oxides covered are those of guanine (1), adenine (2). and hypoxanthine (3) and of related compounds such as 6-mercaptopurine (6-MP) (72). the 6-thioxo analogue of 3, and 6-methylthiopurine, a simple model for azathioprine (78), which were all unknown until recently.

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59 data found. 31 - 59 listedFirst Previous