Special Issue

Kenji Koga's Special Issues, Vol. 66, No. 1, 2005

84 data found. 31 - 60 listedFirst Previous Next Last
Communication | Special issue | Vol 66, No. 1, 2005, pp. 187 - 194
Published online: 29th November, 2005
DOI: 10.3987/COM-05-S(K)73
Asymmetric Synthesis of Crypto-folione and Determination of Its Absolute Configuration

Yuko Matsuoka, Kohsuke Aikawa, Ryo Irie, and Tsutomu Katsuki*

*Department of Chemistry, Faculty of Science, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan


Two possible stereoisomers of cryptofolione, isolated from the Cryptocarya species in South Africa and Brazil, were synthesized in an enantioselective manner by using asymmetric hetero Diels-Alder reaction as the key steps. Comparative evaluation of the 1H NMR , 13C NMR, CD spectra, and specific rotation of the synthetic compounds with those reported in the literature was performed to establish the absolute configuration of cryptofolione to be [6R,10S,12R].

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Communication | Special issue | Vol 66, No. 1, 2005, pp. 195 - 199
Published online: 29th November, 2005
DOI: 10.3987/COM-05-S(K)74
Regression Analysis in the Characterization of Hydrogen-bonded Complex System Involving 2-Pyridone in Terms of Melting Points before and after Complexation

Ichiro Takahashi,* Masahiro Takahashi, Hidehiko Kitajima, Masami Wagi, Yumi Takahashi, Machiko Sabi, Atsushi Hishida, Minoru Hatanaka, Kimio Isa, Akihito Yamano, Akiyo Sakushima, and Shinzo Hosoi

*Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Fukui University, Bunkyo, Fukui 910-8507, Japan


A series of crystalline molecular complexes between 2-pyridone and hydroxy compounds were prepared. Regression analysis utilizing melting points before and after complexation is also discussed.

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Communication | Special issue | Vol 66, No. 1, 2005, pp. 201 - 206
Published online: 29th November, 2005
DOI: 10.3987/COM-05-S(K)75
Bismuth Triflate-Chiral Bipyridine Complex Catalyzed Asymmetric Ring Opening Reactions of meso-Epoxide in Water

Chikako Ogawa, Stéphane Azoulay, and Shu Kobayashi*

*Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan


Catalytic asymmetric ring-opening reactions of meso-epoxides with aromatic amines have been explored. The reactions proceeded in the presence of a catalytic amount of bismuth triflate (Bi(OTf)3), chiral bipyridine ligand (1) and sodium dodecylbenzene sulfonate (SDBS) in pure water to give the corresponding β-amino alcohols in good yields with high enantioselectivities.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 207 - 218
Published online: 28th April, 2005
DOI: 10.3987/COM-05-S(K)1
Synthesis and Transformations of Ethyl (2E)-3-N,N-Dimethylamino-2-(5-ethoxy-1-phenyl-1H-pyrazol-3-yl)propenoate

David Bevk, Ljubo Golic, Amalija Golobic, Jurij Svete,* and Branko Stanovnik*

*Department of Organic Chemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, P.O. Box 537, SI-1000 Ljubljana, Slovenia


The reaction of amines (4a-g) with ethyl (2E)-3-N,N-dimethylamino-2-(5-ethoxy-1-phenyl-1H-pyrazol-3-yl)propenoate (3), prepared in two steps from ethyl (4,5-dihydro-5-oxo-1-phenyl-1H-pyrazol-3-yl)acetate (1), gave ethyl (2E)-2-(5-ethoxy-1-phenyl-1H-pyrazol-3-yl)-3-(substituted amino)propenoates (5a-g). The reaction of compound (3) with 2-aminopyridine (4h), 3 amino-1H-pyrazole (4i), 2H-pyran-2-one (6a), and 5,5-dimethylcyclohexane-1,3-dione (6b) afforded 3-(pyrazol-3-yl)pyridopyrimidinone (7a), 6-(pyrazol-3-yl)pyridopyri-midinone (7b), 3-(pyrazol-3-yl)pyranopyrandione (7c), and 3-(pyrazol-3-yl)-chromenedione (7d), respectively.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 219 - 228
Published online: 13th September, 2005
DOI: 10.3987/COM-05-S(K)8
Synthesis of (4R,5S)-Melithiazols B and M

Hiroyuki Akita,* Takamitsu Sasaki, Hiroyuki Takayama, and Keisuke Kato

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


A Wittig reaction between the reported (+)-chiral aldehyde [(4R,5R)-5] and the phosphoranylide derived from the bithiazole-type phosphonium iodide (6) using lithium bis(trimethylsilyl)amide afforded the (+)-melithiazol B (1), whose spectral data were identical with those of the natural (+)-1 from the myxobacterium Archangium gephyra, strain Ar 7747. Moreover, the selective olefin formation between (+)-(4R,5R)-5 and the bithiazole-type sulfone [(±)-7] followed by transformation gave the (+)-melithiazol M (2), whose spectral data were identical with those of the natural (+)-2 from the myxobacterium Archangium gephyra, strain Ar 7747.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 229 - 240
Published online: 8th September, 2005
DOI: 10.3987/COM-05-S(K)10
Effective Methods for Introducing Some Aryl and Heteroaryl Substituent onto 1-Azaazulene Nuclei

Noritaka Abe,* Megumi Tanaka, Takeshi Maeda, Hiroyuki Fujii, and Akikazu Kakehi

*Department of Chemistry, Faculty of Science, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8512, Japan


Introduction of aryl and heteroaryl groups onto 1-azaazulene ring was achieved by addition-elimination reaction and Suzuki coupling. Reaction of 2-chloro-1-azaazulenes with 2-aryllithium and 2-heteroaryllithium followed by dehydrogenation with o-chloranil gave 8-aryl- and 8-heteroaryl-2-chloro-1-azaazulene in good yields. Suzuki coupling of 3-iodo-1-azaazulenenswith phenylboronic acid in the presence of Pd catalyst afforded 3-phenyl-1-azaazulenes in excellent yield. Suzuki coupling of 2-bromo-1-azaazulenes with phenylboronic acid gave 2-phenyl-1-azaazulenes. Suzuki coupling of 2,3-dibromo-1-azaazulene with phenylboronic acid preferentially occurred at C-2. Reaction of 3-iodo-1-azaazulene with bis(pinacolato)diboron produced 3,3'-bis(1-azaazulene) derivative.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 241 - 249
Published online: 27th September, 2005
DOI: 10.3987/COM-05-S(K)11
Synthesis of Tetrahydro-β-carbolines via Radical Cyclization of 2-Alkenylthioanilides

Manami Iwadate, Tohru Yamashita, Hidetoshi Tokuyama, and Tohru Fukuyama*

*Graduate School of Pharmaceutical Sciences, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan


A synthetic protocol of 1,2,3,4-tetrahydro-β-carbolines from o-alkenylaniline and α-amino acid was developed. Condensation of α-amino acids with 2-alkenylaniline derived from quinoline gave o-alkenylanilides. Conversion of the anilides to thioanilides was effected with Lawesson’s reagent in the presence of pyridine, which was crucial to suppress epimerization of the chiral center. After formation of an indole skeleton by radical cyclization, 1,2,3,4-tetrahydro-β-carbolines were obtained via intramolecular N-alkylation.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 251 - 261
Published online: 14th October, 2005
DOI: 10.3987/COM-05-S(K)15
Synthesis of Phospholane 1-Oxide Having Oxygen Functional Groups from a 4-Bromobutylphoshinate Derivatives

Tadashi Hanaya,* Shigeru Kawase, and Hiroshi Yamamoto

*Department of Chemistry, Faculty of Science, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan


Ethyl 4-bromo-2,3-dimethoxybutyl(phenyl)phosphinate (10a) was prepared from 2,3-di-O-methyl-L-threitol (12) in five steps. Reduction of 10a with sodium dihydrobis(2-methoxyethoxy)aluminate, followed by the action of hydrogen peroxide, afforded 3,4-dimethoxy-1-phenylphospholane 1-oxide (3), while the reaction of 10a with magnesium in boiling THF resulted in the formation of ethyl 2-methoxy-3-butenyl(phenyl)phosphinate (26).

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 263 - 273
Published online: 11th October, 2005
DOI: 10.3987/COM-05-S(K)16
Planar-Chiral Ionic Liquids. Cyclophane-Type Imidazolium Salts with a C(2)-C(4) Bridge

Yasuhiro Ishida, Hiroyuki Miyauchi, and Kazuhiko Saigo*

*Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan


Novel chiral ionic liquids with planar chirality was synthesized, which were based on cyclophane-type imidazolium salts with a dodecamethylene bridge connecting the imidazolium C(2) and C(4) positions. Their potential utility as chiral solvents was demonstrated by 1H NMR spectroscopy and DSC measurement.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 275 - 283
Published online: 30th September, 2005
DOI: 10.3987/COM-05-S(K)18
Synthesis and Properties of (1-Azulenyl)di(3-indolyl)methylium Hexafluorophosphates

Shigeru Kikuchi,* Makiko Iki, Chizu Ikeda, and Kimiaki Imafuku*

*Department of Chemistry, Faculty of Science, Kumamoto University, Kurokami 2-39-1, Kumamoto 860-8555, Japan


(1-Azulenyl)di(3-indolyl)methanes (3a-c;5a,b) were synthesized by the acid-catalyzed condensation of methyl 3-formylazulene-1-carboxylate (1) with indoles (2a-d) and converted to the corresponding (1-azulenyl)di(3-indolyl)methylium hexafluorophosphates (6a-d). On the basis of their pKR+ values (~ 13), the methyl cations (6a-d) were found to be comparably stable to tri(1-azulenyl)methyl cations.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 285 - 297
Published online: 14th October, 2005
DOI: 10.3987/COM-05-S(K)20
Allosteric Binding of Alkali Metal Ions to a Pseudocryptand Formed by a C-Pivot Tripodal Ligand Containing 3-Hydroxy-2(1H)-pyridinone and Ga(III)

Akira Katoh,* Hidenori Kudo, and Ryota Saito

*Department of Materials and Life Science, Faculty of Science and Technology, Seikei University, Musashino-shi, Tokyo 180-8633, Japan


A novel C-pivot tripodal hexadentate ligand (3,2-HOPOHL) composed of 3-hydroxy-2(1H)-pyridinone as a bidentate ligand, the ethyleneoxy chain as a spacer, and tris(carboxyric acid) as an anchor was synthesized. 3,2-HOPOHL recognized only Na+ ion, suggesting that it pre-organized a cavity due to the electrostatic interaction among the 2(1H)-pyridinone rings. UV-VIS spectroscopic analysis indicated that 3,2-HOPOHL formed a stable intramolecular 1:1 Fe(III) complex in aqueous solution. The stability constant (log K) of 3,2-HOPOHL-Fe(III) complex was estimated to be 27.6 from the competitive reaction with EDTA. 1H-NMR titration of 3,2-HOPOHL-Ga(III) complex with Na+ and K+ ions in CDCl3-CD3CN indicated the formation of 1:1 complexes. The binding constants of Na+- and K+-3,2-HOPOHL-Ga(III) complexes were estimated to be 3.3x103 and 7.8x103 M-1, respectively, the ion selectivity of K+ toward Na+ being more than two-fold.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 299 - 308
Published online: 18th October, 2005
DOI: 10.3987/COM-05-S(K)22
Synthesis of Novel 5-Acetoacetyl-3-acetyl-2-pyridone Derivatives by the Ring-Transformation of 6-Methyl-1,3-oxazin-4-ones

Hidekazu Ouchi,* Hisao Saito, Yutaka Yamamoto, and Hiroki Takahata*

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


The synthesis of novel poly-functionalized 5-acetoacetyl-3-acetyl-2-pyridone derivatives was achieved via the ring-transformation of 6-methyl-4H-1,3-oxazin-4-ones with 3-methylisoxazole derivatives, followed by reductive cleavage of the isoxazole ring and hydrolysis.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 309 - 317
Published online: 1st November, 2005
DOI: 10.3987/COM-05-S(K)23
Hypervalent Iodine(III) Reagent-promoted Rearrangement and Subsequent Oxidative Ring Cleavage of Cyclic 2,3-Epoxy-1-alcohol Derivatives

Yasuyuki Kita,* Satoshi Matsuda, Eri Fujii, Shinji Kitagaki, Ryoko Inoguchi, Kayoko Hata, and Hiromichi Fujioka

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


The rearrangements of 2,3-epoxy alcohol derivatives were achieved using the hypervalent iodine(III) reagent, phenyliodine(III) bis(trifluoroacetate) (PIFA). In the case of 2,3-epoxy alcohols subsequent oxidative ring cleavage occurred to give ω-formylalkanoic acids.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 319 - 332
Published online: 21st October, 2005
DOI: 10.3987/COM-05-S(K)27
Novel 1,1’,5,5’-Tetraaryl-2,2’-bipyrroles: Their Synthesis and Physical Properties

Shoji Matsumoto, Takamitsu Kobayashi, and Katsuyuki Ogura*

*Department of Applied Chemistry, Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan


We report a new type of 2,2’-bipyrrole derivatives that bear four aryl groups at the 1, 1’, 5 and 5’ positions. These compounds were synthesized by two routes: (i) the reaction of 1,8-diaryl-2,7-ditosyl-1,7-octadiene-3,5-diynes (4) with anilines was performed in the presence of CuCl at 150 °C; (ii) the above compound (4) was converted to a 1-aryl-4-(1,5-diaryl-2-pyrrolyl)butadiynes (7), which were subjected to the reaction with anilines in the presence of CuCl in DMF at 150 °C. The conformation between the two pyrrole rings of the 1,1’,5,5’-tetraaryl-2,2’-bipyrrole is also discussed from X-Ray crystal structure and UV-VIS spectrum.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 333 - 339
Published online: 30th September, 2005
DOI: 10.3987/COM-05-S(K)28
Addition of 2-Oxazolidinones to Arylidenecyclopropanes: A Highly Efficient Method for the Preparation of gem-Aryl Disubstituted Homoallylic Oxazolidinones

Amal I. Siriwardana, Kalum K. A. D. S. Kathriarachchi, Itaru Nakamura, and Yoshinori Yamamoto*

*Department of Chemistry, Graduate School of Science, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan


The copper-catalyzed reaction of arylidenecyclopropanes (1) with 2-
oxazolidinone (2) gave the corresponding homoallylic oxazolidinones (3) in good to high yields. For example, the reaction of diphenylmethylenecyclopropane (1a), {bis(p-tolyl)methylenecyclopropane (1b), and {bis(p-anisyl)methylene}cyclopropane (1d) in the presence of 10 mol% of Cu(OTf)2 without solvent proceeded at 120 °C, giving the corresponding homoallylic oxazolidinones (3a, 3b, and 3d) in 89, 80, and 58% yields, respectively.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 341 - 346
Published online: 11th October, 2005
DOI: 10.3987/COM-05-S(K)29
Alternative Synthesis of (-)-Geissman-Waiss Lactone, a Key Intermediate of Necine Bases

Toshio Honda* and Sae Matsumoto

*Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan


A facile synthetic route to (-)-Geissman-Waiss lactone, a key intermediate of necine bases, was established by employing ring closing metathesis (RCM), followed by intramolecular Michael reaction of the resulting α,β-unsaturated lactone, as the key steps.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 347 - 359
Published online: 21st October, 2005
DOI: 10.3987/COM-05-S(K)32
Guanidine-catalyzed Asymmetric Addition Reactions: Michael Reaction of Cyclopentenone with Dibenzyl Malonates and Epoxidation of Chalcone

Takuya Kumamoto, Keiko Ebine, Miyuki Endo, Yukari Araki, Yuji Fushimi, Ikue Miyamoto, Tsutomu Ishikawa,* Toshio Isobe, and Keiko Fukuda

*Graduate School of Pharmaceutical Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan


Several kinds of modified guanidines designed by us were applied to two types of asymmetric synthesis as superbases: Michael reactions of cyclopentenone with dibenzyl malonates and epoxidation of chalcone. Good to moderate asymmetric inductions were observed in these guanidine-catalyzed reactions.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 361 - 369
Published online: 21st October, 2005
DOI: 10.3987/COM-05-S(K)36
Synthesis of Base-selectively Deuterium-labelled Nucleosides by the Pd/C-catalyzed H-D Exchange Reaction in Deuterium Oxide

Hiroyoshi Esaki, Fumiyo Aoki, Tomohiro Maegawa, Kosaku Hirota, and Hironao Sajiki*

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


The D2 gas-free and base-selective H-D exchange reaction of nucleosides was developed. It discloses a convenient route to the post-synthetic incorporation of deuteriums into the base moiety of nucleic acids with high deuterium efficiency.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 371 - 383
Published online: 1st November, 2005
DOI: 10.3987/COM-05-S(K)38
Synthesis of a Pseudoenantiomer of β-Isocupreidine (β-ICD), a Chiral Amine Catalyst for Asymmetric Baylis-Hillman Reactions

Ayako Nakano, Keisuke Takahashi, Jun Ishihara, and Susumi Hatakeyama*

*Faculty of Pharmaceutical Sciences, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki 852-8521, Japan


(3S,8S,9R)-3,9-Epoxy-6’-hydroxy-11-norcinconane (23), a pseudoenantiomer of β-isocupreidine (β-ICD), was synthesized starting with a fragmentation reaction of 10-bromo-10,11-dihydroquinine, prepared from quinine. Baylis-Hillman reaction of benzaldehyde with 1,1,1,3,3,3-hexafluoroisopropyl acrylate (HFIPA) using 23 as a chiral amine catalyst gave the corresponding S-enriched adduct in high optical purity (93% ee) in contrast to the β-ICD- catalyzed reaction which affords R-enriched adducts.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 385 - 403
Published online: 21st October, 2005
DOI: 10.3987/COM-05-S(K)41
Asymmetric Synthesis of β-Substituted γ-Lactams Employing the SAMP-/RAMP-Hydrazone Methodology. Application to the Synthesis of (R)-(-)-Baclofen

Dieter Enders* and Oliver Niemeier

*Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aache, Germany


A short and efficient asymmetric synthesis of β-substituted γ-lactams is described. Key steps are the α-alkylation of aldehyde SAMP-hydrazones with alkyl bromoacetates, their MMPP mediated conversion to the corresponding nitriles and a reductive cyclization with Raney Ni or Ni boride to the title pyrrolidin-2-ones. The β-substituted γ-lactams are obtained in three steps, good overall yields (27-78%) and excellent enantiomeric excesses (ee = 93-99%). The applicability of this procedure for the asymmetric synthesis of GABAs (γ-aminobutyric acids) is demonstrated for (R)-(-)-baclofen hydrochloride, which is obtained in 4 steps, 55% yield and 94% ee.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 405 - 431
Published online: 15th November, 2005
DOI: 10.3987/COM-05-S(K)42
Remarkable Effect of Subtle Structural Change of Chiral Pseudo-18-Crown-6 on Enantiomer-Selectivity in Complexation with Chiral Amino Alcohols

Keiji Hirose,* Pakatip Aksharanandana, Michiko Suzuki, Kiyoshi Wada, Koichiro Naemura, and Yoshito Tobe

*Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan


Chiral receptors [(S,S)-1] and [(S,S,S,S)-2] having 1,2-dialkoxy-1-(3,5-dimethylphenyl)ethane and 1,2-dialkoxy-1-(3,5-dimethyl phenyl)cyclohexane as chiral building blocks, respectively, were prepared. Thermodynamic parameters of complexations of these and structurally related receptors [(S,S)-3] and [(S,S,S,S)-4] with 2-amino-1-propanol (5), 2-amino-2-phenylethanol (6), and 3-methylbutan-1-ol (7) in chloroform were determined. It was found that the host-guest systems that have same enantiomer-selectivity at 25 °C showed opposite selectivity in the enthalpy term. For example, complexations of both (S,S)-1 and (S,S)-3 with 5 are R-selective at 25 °C (ΔΔG = 2.2 and 3.8 kJ mol-1, respectively), whereas in terms of the enthalpy of complexation the former is S-selective (ΔΔH = 22 kJ mol-1) but the latter is R-selective (ΔΔH = 10 kJ mol-1).

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 433 - 440
Published online: 21st October, 2005
DOI: 10.3987/COM-05-S(K)49
Synthesis of New Chiral Bis-oxazoline Ligand with Zinc Triflate-Selective Chelating Ability and Its Applications

Kazuishi Makino, Ikuko Ogawa, and Yasumasa Hamada*

*Graduate School of Pharmaceutical Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan


New chiral bis-oxazoline ligand (10) with a dihydroanthracene skeleton was synthesized and its application to enantioselective Diels-Alder reaction and Henry reaction has revealed extremely zinc triflate-selective chelating ability of 10.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 441 - 451
Published online: 14th October, 2005
DOI: 10.3987/COM-05-S(K)52
Short-Step Synthesis of 5-Thio-L-hexopyranoses from D-Glyconothio-O-lactones

Daisuke Sawada, Shinya Sasayama, Hideyo Takahashi, and Shiro Ikegami*

*Faculty of Pharmaceutical Sciences, Teikyo University, 1091-1, Sagamiko, Kanagawa 199-0195, Japan


We developed a synthetic method for 5-thio-L-hexopyranose from D-glyconothio-O-lactone using the initial ring-opening reaction and subsequent recyclization under Mitsunobu conditions. Using this method, only a three-step transformation is required from D-glyconothio-O-lactone to 5-thio-L-glyconolactone.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 453 - 468
Published online: 15th November, 2005
DOI: 10.3987/COM-05-S(K)54
Synthesis of Di- and Trisaccharides Comprising D-Fructopyranose with β2 → 1 Glycosidic Linkage Using β-D-fructopyranosyl Fluoride as the Fructosyl Donor

Eisuke Kaji,* Emiko Kurimoto, Reiko Saiga, Ayako Matsuura, Kazuho Harada, and Takashi Nishino

*School of Pharmaceutical Sciences, Kitasato University, Shirokane 5-9-1, Minato-ku, Tokyo 108-8641, Japan


D-Fructose was converted into a stable, suitably protected fructosyl donor for iterative glycosylation, i.e., 1-O-acetyl-3,4,5-tri-O-benzyl-β-D-fructopyranosyl fluoride and a fructosyl acceptor, methoxymethyl 3,4,5-tri-O-benzyl-β-D-fructopyranoside in good yields. Glycosylation of the both substrates provided di- and trisaccharides comprising β-D-fructopyranose with β (2 →1)-interglycosidic linkage.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 469 - 479
Published online: 15th November, 2005
DOI: 10.3987/COM-05-S(K)56
Synthesis of 25-Hydroxy-19-norvitamin D3 Analogs and Their Antiproliferative Activities on Prostate Cells

Midori A. Arai, Ryuji Tsutsumi, Hideki Hara, Tai C. Chen, Toshiyuki Sakaki, Naoko Urushino, Kuniyo Inouye, and Atsushi Kittaka*

*Faculty of Pharmaceutical Sciences, Teikyo University, 1091-1 Suarashi, Sagamiko-machi, Tsukui-gun, Kanagawa 199-0195, Japan


Synthesis of 25-hydroxy-19-norvitamin D3 derivatives as prohormone type agents for anti-prostate diseases was accomplished utilizing Julia-type olefination. Synthesized compounds showed potent antiproliferative activity on an immortalized normal prostate cell line, PZ-HPV-7, which has high 1α-hydroxylase activity. Furthermore, we demonstrated that 25-hydroxy-19-norvitamin D3 was hydroxylated at the 1α position to form 1α,25-dihydroxy-19-norvitamin D3 by a recombinant human 1α-hydroxylase (CYP27B1) in a cell-free system.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 481 - 502
Published online: 18th November, 2005
DOI: 10.3987/COM-05-S(K)58
Efficient Synthesis of Functionalized Benzazepine Derivatives Utilizing Intramolecular Mitsunobu Reaction

Tadaaki Ohtani,* Yoshikazu Kawano, Kazuyoshi Kitano, Jun Matsubara, Makoto Komatsu, Minoru Uchida, Fujio Tabusa, and Yoshimitsu Nagao

*Tokushima Research Institute, Otsuka Pharmaceutical Co., Ltd., Kagasuno 463-10, Kawauchi-cho, Tokushima 771-0192, Japan


The 5-hydroxy-2,3,4,5-tetrahydro-1H-benzazepine derivative (2), which is a typical metabolite of mozavaptan (1) having the 2,3,4,5-tetrahydro-1H-benzazepine skeleton, was synthesized by utilizing the intramolecular Mitsunobu reaction of the corresponding 2-(4-hydroxybutyl)aniline derivative. In the intramolecular Mitsunobu reaction, effect of the substituent group on nitrogen atom, influence of the functional group applying to synthesis of the other metabolites (3, 4 and 5) and utilization of synthesis of 2-substituent benzazepine derivatives were investigated.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 503 - 509
Published online: 28th October, 2005
DOI: 10.3987/COM-05-S(K)60
Novel Synthesis of 4-Arylsulfenyl-3-hydroxy-2-pyrone: One Pot Substitution-Rearrangement-Cyclization Reaction of Acetonide Protected 4,5-Dihydroxy-2-chloroglycidic Ester by Sodium Arylthiolate

Takuzo Komiyama, Yutaka Takaguchi, and Sadao Tsuboi*

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


Treatment of acetonide protected 4,5-dihydroxy-2-chloroglycidic ester with sodium arylthiolate gave 4-arylsulfenyl-3-hydroxy-2-pyrone in excellent to good yields in one pot.

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Paper | Special issue | Vol 66, No. 1, 2005, pp. 511 - 525
Published online: 1st November, 2005
DOI: 10.3987/COM-05-S(K)61
Stereoselective Synthesis of 2,5-Di- and 2,2,5-Trisubstituted Pyrrolidines by Allylation Reaction of Acyliminium Ion

Tetsuro Shinada,* Makoto Hamada, Masanori Kawasaki, and Yasufumi Ohfune*

*Faculty of Science, Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan


Allylation reactions of allytrimethylsilane and an allylcopper reagent to acyliminium ions derived from several 2-monosubstituted and 2,2-disubstituted pyrrolidinones were examined. These reactions proceeded in a stereoselective manner to give the corresponding allylated adducts. The stereochemical outcomes of these reactions were dependent upon the allylating reagents or the structures of the acyliminium ions.

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Note | Special issue | Vol 66, No. 1, 2005, pp. 527 - 530
Published online: 18th April, 2005
DOI: 10.3987/COM-05-S(K)2
Palladium-assisted Biaryl Coupling Reaction of 1-(2-Iodobenzoyl)-1,2,3,4-tetrahydroquinoline

Takashi Harayama,* Tomonori Sato, Akihiro Hori, Hitoshi Abe, and Yasuo Takeuchi

*Faculty of Pharmaceutical Sciences, Okayama University,


The biaryl coupling reaction of 1-(2-iodobenzoyl)-1,2,3,4-tetrahydroquinoline using Pd reagent was examined. The reaction proceeded smoothly to produce 5,6-dihydro-4H,8H-pyrido[3,2,1-de]phenanthridin-8-one in excellent yield.

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Note | Special issue | Vol 66, No. 1, 2005, pp. 531 - 534
Published online: 8th July, 2005
DOI: 10.3987/COM-05-S(K)4
Diol Derivative of (3-Trifluoromethyl)phenyldiazirine for Post-labeling of Photocrosslink

Makoto Hashimoto* and Yasumaru Hatanaka

*Department of Bioresource Science, Obihiro Univ.of Agriculture and Veterinary Med., Inada-cho, Obihiro, Hokkaido 080-8555, Japan


3-Trifluoromethylphenyldiazirinylated diol derivative was utilized to introduce an aldehyde by periodate oxidation, followed by the formation of a Schiff base with biotin hydrazide on a PVDF membrane for post-labeling of photocrosslinked proteins. The biotin hydrazide was able to post-label the 2.5 x 10-13 mole of closslinked component for chemiluminescent visualization.

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