HETEROCYCLES
An International Journal for Reviews and Communications in Heterocyclic ChemistryWeb Edition ISSN: 1881-0942
Published online by The Japan Institute of Heterocyclic Chemistry
Special Issue
Kenji Koga's Special Issues, Vol. 66, No. 1, 2005
Published online: 29th November, 2005
■ 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
Abstract
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].
Published online: 29th November, 2005
■ 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
Abstract
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.
Published online: 29th November, 2005
■ 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
Abstract
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.
Published online: 28th April, 2005
■ 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
Abstract
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.
Published online: 13th September, 2005
■ 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
Abstract
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.
Published online: 8th September, 2005
■ 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
Abstract
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.
Published online: 27th September, 2005
■ 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
Abstract
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.
Published online: 14th October, 2005
■ 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
Abstract
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).
Published online: 11th October, 2005
■ 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
Abstract
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.
Published online: 30th September, 2005
■ 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
Abstract
(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.
Published online: 14th October, 2005
■ 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
Abstract
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.
Published online: 18th October, 2005
■ 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
Abstract
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.
Published online: 1st November, 2005
■ 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
Abstract
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.
Published online: 21st October, 2005
■ 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
Abstract
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.
Published online: 30th September, 2005
■ 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
Abstract
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.
Published online: 11th October, 2005
■ 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
Abstract
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.
Published online: 21st October, 2005
■ 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
Abstract
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.
Published online: 21st October, 2005
■ 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
Abstract
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.
Published online: 1st November, 2005
■ 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
Abstract
(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.
Published online: 21st October, 2005
■ 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
Abstract
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.
Published online: 15th November, 2005
■ 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
Abstract
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).
Published online: 21st October, 2005
■ 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
Abstract
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.
Published online: 14th October, 2005
■ 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
Abstract
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.
Published online: 15th November, 2005
■ 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
Abstract
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.
Published online: 15th November, 2005
■ 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
Abstract
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.
Published online: 18th November, 2005
■ 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
Abstract
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.
Published online: 28th October, 2005
■ 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
Abstract
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.
Published online: 1st November, 2005
■ 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
Abstract
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.
Published online: 18th April, 2005
■ 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,
Abstract
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.
Published online: 8th July, 2005
■ 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
Abstract
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.