HETEROCYCLES
An International Journal for Reviews and Communications in Heterocyclic ChemistryWeb Edition ISSN: 1881-0942
Published online by The Japan Institute of Heterocyclic Chemistry
Regular Issue
Vol. 41, No. 11, 1995
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■ Synthesis of 2-(Benzopyran-4-yl)pyridine N-Oxide K+ Channnel Opener via Palladium-catalyzed Cross-Coupling Reaction
Tadakatsu Takahashi, Hiroshi Koga,* Haruhiko Sato, Takenori Ishizawa, and Naoki Taka
*Fuji-gotemba Research Laboratories, Chugai Pharmaceutical Co., Ltd., 1-135, Komakado, Gotemba, Shizuoka 412, Japan
Abstract
2-(Benzopyran-4-yl)pyridine N-oxide (3) was prepared from 2-chlorozinciopyridine N-oxide and benzopyran-4-yl triflate in the presence of tetrakis(triphenylphosphine)palladium.
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■ A Synthetic Entry to 1- and 2-Aminopyrazolo[3,4-d]-1,2,3-triazoles
Chiara B. Vicentini, Valeria Ferretti, Augusto C. Veronese, and Paolo Giori*
*Dipartimento di Scienze Farmaceutiche, Università di Ferrara, 44100-FERRARA, Italy
Abstract
2-Aminopyrazolo[3,4-d]-1,2,3-triazole (4) and 1-aminopyrazolo[3,4-d]-1,2,3-triazole (5) were prepared by direct amination of pyrazolo[3,4-d]-1,2,3-triazole with hydroxylamine O-sulphonic acid in aqueous potassium hydroxide. The ratio of 4 to 5 was 2 : 3.
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■ Isolation of Δ3-1,2,3-Thiadiazolin-1-ones, a Key Intermediate of the Hurd-Mori Reaction
Mikako Fujita, Kohei Nimura, Takeo Kobori,* Tamejiro Hiyama, and Kiyosi Kondo
*Sagami Chemical Research Center, 4-4-1 Nishiohnuma, Sagamihara, Kanagawa 229, Japan
Abstract
The Hurd-Mori reaction of N-ethoxycarbonyl- or p-toluenesulfonylhydrazones of 1,2-alkanediones (1) gave Δ3-1,2,3-thiadiazolin-1-ones (2) as each sole isolable product. Upon HCl treatment 2b was converted into 1,2,3-thiadiazole, an expected product of the Hurd-Mori reaction.
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■ Synthesis and Chemiluminescence of 3-Biphenylyl-4,4-diisopropyl-3-methoxy-1,2-Dioxetanes
Masakatsu Matsumoto,* Hiroyuki Suganuma, Mitsunori Azami, Naoko Aoshima, and Hiroshi Mutoh
*Department of Materials Science, Kanagawa University, Tsuchiya, Hiratsuka, Kanagawa 259, Japan
Abstract
Five 3-biphenylyl-4,4-diisopropyl-3-methoxy-1,2-dioxetanes (5) with a tert-butyldimethylsiloxy group at the appropriate position on the aromatic ring were synthesized and their fluoride-induced chemiluminescence were examined.
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■ A Short Synthetic Approach to Enantiomerically Pure (-)-Anisomycin
Hidemi Yoda,* Tomohito Nakajima, Hiroyasu Yamazaki, and Kunihiko Takabe
*Department of Molecular Science, Faculty of Engineering, Shizuoka University, Hamamatsu 432, Japan
Abstract
A convenient enantiomerically pure route to an antibiotic, natural (-)-anisomycin has been developed in a short number of steps by featuring the stereocontrolled elaboration of the functionalized homochiral lactam derived from 2,3,5-tri-O-benzyl-β-L-arabinofuranose involving no separation of stereoisomers through the entire sequence.
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■ A Simple and Efficient One Pot Synthesis of 4-Oxo-spiro[thiazolidine-2,2'(1'H)quinolines] and Their Reactions with DDQ
Harald Walter*
*DIvision Crop Protection Research and Development Disease Control, Ciba-Geigy Limited, Postfach, CH-4002 Basel, Switzerland
Abstract
The treatment of two equivalents of the anion of 3,4-dihydro-1H-quinoline-2-thione (3) with one equivalent of one of the N-substituted 2-bromoacetamides (4a-d) at room temperature afforded the title compounds in good yields (Scheme 1, Table 1). The reaction of the compounds (6a-d) with DDQ at room temperature and 90 °C was studied. Mechanistic aspects of the processes are briefly discussed.
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■ A Novel Aspect on the 1,2-Alkyl Migration Reaction with Trialkyl 1-Substituted Indol-2-ylborates
Minoru Ishikura* and Isao Agata*
*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-02, Japan
Abstract
Intramolecular 1,2-alkyl migration reaction of trialkyl(1-methoxyindol-2-yl)borates and trialkyl(1-methoxymethylindol-2-yl)borates gave rise to 2-alkylindoles and 2-alkyl-1-methylindoles, respectively.
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■ Synthesis of Tricyclic Benzazepines and Their Dopamine D1- and D2-Affinity
Eva Horn Jensen, Per Halfdan Nielsen, and Rolf Hohlweg*
*Marine Chemistry Section, The H. C. Ørsted Institute, Universitetsparken 5, DK-2100 Copenhagen, Denmark
Abstract
A new group of angular 8,9-annelated 3-benzazepines has been found to be potent and selective dopamine D1-receptor antagonists of interest as possible pharmaceuticals in the treatment of schizophrenia. The synthesis of three new conformationally constrained representatives of this group of benzazepines is described and their affinity to the D1-receptor evaluated. Although none of these proved superior to the previously examined compounds, useful information on the receptor binding site was obtained.
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■ Reaction of 5-Aminobenzotriazoles with Methyl Propiolate. Formation of Triazolo[4,5-f]quinolines and Related Compounds. Unusual Products in the Michael Addition Reaction of 2-Methyl-2H-5-aminobenzotriazole
Paolo Sanna*, Piera Attilia Sequi, Sandra Piras, and Giuseppe Paglietti
*Instituto di Chimica Farmaceutica e Tossicologica, University of Sassari, Via Muroni 23, 07100 Sassari, Italy
Abstract
Reaction of 5-aminobenzotriazoles (1b-d) with methyl propiolate gives (Z/E)-3-[1(2)(3)-methyl(benzotriazol-5-yl)]aminomonopropenoates (5b-d) and (E)-3-[1(2)(3)-methyl(benzotriazol-5-yl)]aminobispropenoates (6b-d), while in the case of 1a addition took place on the nitrogen of the triazole ring to give mixtures of (E)-3-(5-aminobenzotriazol-1(2)(3)-yl)propenoates (2, 3, 4). Mono- (5b-d) and bis-adducts (6b-d) underwent further reaction which also led to the isolation of triazolo[4,5-f]quinolines, of a triazolo[4,5-f]carbostyril and 1-[benzotriazol-5-yl]-2-pyridones. Formation of these compounds depends on the reaction conditions: the solvent employed and the temperature. Thermal cyclization of Michael adduct (Z/E)-(5c) gave triazoloquinolinone (9c) and the rearranged product (13) in various ratio depending on the concentration of Dowtherm used.
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■ A Facile Route for the Synthesis of Some New Spiro[indoline-3,3'-indan]-2,1'-dione Derivatives
Marzoog S. Al-Thebeiti* and Maher F. El-Zohry
*Department of Chemistry, Faculty of Applied Sciences, Umm Al-Qura University, Makkah Almukkarramah, P. O. Box 6876, Saudi Arabia
Abstract
Indole-2,3-dione (1) was treated with malonic acid in a mixture of ethanol/pyridine to afford 1-[3-(2-oxoindolinylidene]acetic acid (5). Compound (5) reacted with arenes in the presence of aluminium chloride as catalyst to yield spiro[indoline-3,3’-indan]-2,1’-dione derivatives (6a-e).
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■ Synthesis of a 1,2-Dithiin Mediated by Electrophilic Reagents
Paul Salama,* Marc Poirier, and Marc Caissie
*Department of Chemistry and Biochemistry, Université de Moncton, Moncton, New Brunswick, E1A 3E9, Canada
Abstract
The one step conversion of bis-thiocamphor into its corresponding 1,2-dithiin is achieved by using various electrophilic halides. The influences of solvent, temperature and acidity of the medium revealed that it is possible to selectively direct the reaction towards, either the 1,2-dithiin or a mixture of the thiophene/trithiepin homologues.
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■ Synthesis of a Novel 6,5-Bicyclic Hexahydropyridazine Derivative
Peter S. Dragovich*, Hiroki Tada, and Ru Zhou
*Agouron Pharmaceuticals, Inc., 3565 General Atomics Court, San Diego, California 92121, U.S.A.
Abstract
A convergent synthesis of the 6,5-bicyclic hexahydropyridazine derivative (3) is described in which (3S)-N1-Cbz-piperazic acid methyl ester (4) is coupled with the functionalized carboxylic acid fragment (9). The Sharpless asymmetric dihydroxylation reaction (AD) of the 1,1-disubstituted olefin (6) is utilized in the preparation of 9 and is observed to produce the corresponding diol with 44% enantiomeric excess and R stereochemistry.
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■ Enantiospecific Synthesis of 2,3,5-Substituted Piperidines as Analogues of Nojirimycin
Nicholas Bentley, Christian S. Dowdeswell, and Gurdial Singh*
*School of Science and Technology, University of Teesside, Middlesbrough, Cleveland, TS1 3BA, U.K.
Abstract
Chiral 2,3,5-trihydroxypiperidines have been synthesised from the readily available 1,2:5,6-di-O-isopropylidene-α-D-glucofuranose.
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■ Synthesis of 2-Alkylthio Analogues of AZT and Their Activity against HIV-1
Magdy A. Zahran, Ahmed E.-S. Abdel-Megied, Adel A.-H. Abdel-Rahman, Ali El-Emam, Erik B. Pedersen,* and Claus Nielsen
*Department of Chemistry, Odense University, Odense M, Denmark
Abstract
S2-Alkylated 3’-azido-2’,3’-dideoxy-2-thiouridines (5) and their corresponding α anomers have been synthesized through two routes: 1) by condensation of silylated 2-alkylthiopyridin-4(1H)-ones (2) with methyl 3-azido-5-O-(tert-butyldiphenylsilyl)-2,3-dideoxy-α,β-D-erythro-pentofuranoside (3); 2) by condensation with methyl 5-O-(tert-butyldiphenylsilyl)-2,3-dideoxy-3-iodo-α,β-D-threo-pentofuranoside (7), followed by reaction of the obtained iodonucleoside (8) with sodium azide to give the protected azidonucleoside (10) and the 3’,4’-didehydro-2’,3’-dideoxy nucleoside (11).
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■ Convenient Synthesis of Cycloalkene-fused Phthalazinones
Norbert Haider*
*Institute of Pharmaceutical Chemistry, University of Vienna, Althanstrasse14, A-1090 Vienna, Austria
Abstract
A series of cycloalkene-annelated phthalazin-1(2H)-ones (2 - 5) was prepared in high yields by a one-pot procedure, employing pyridazino[4,5-d]pyridazin-1(2H)-ones (1) as azadienes and cyclic enamines as dienophiles in an inverse-electron-demand Diels-Alder reaction, followed by acid-catalyzed aromatization.
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■ Reaction Products of 1,3-Indandione with Heteroaromatic Carbaldehydes: Synthesis, Structure and NMR-Investigations
Claudia Franz, Gottfried Heinisch*, Wolfgang Holzer,* Kurt Mereiter, Barbara Strobl, and Changtu Zheng
*Institute of Pharmaceutical Chemistry, University of Vienna, Pharmaziezentrum, Althanstraße14, A-1090 Vienna, Austria
Abstract
The synthesis of 1:1 condensation products from 1,3-indandione and various heteroaromatic carbaldehydes is described. Employment of aldehydes derived from π-deficient N-heteroaromatics was found to lead also to 2:1 adducts via Michael-addition of the 1,3-diketone to the initially formed 1:1 condensation products. 1H and 13C nmr spectroscopic studies of the products obtained and of known congeners are presented. The structure of the 2:1 adduct resulting from reaction of 1,3-indandione and 4-quinolinecarbaldehyde was determined by X-ray analysis.
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■ Characterization of Decamethyl and Ethoxycarbonyl Pentaphyrins
Richmond E. Danso-Danquah, Lily Y. Xie, and David Dolphin*
*Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, B.C., Canada, V6T1Z1
Abstract
The syntheses of decamethyl- and ethoxycarbonylpentaphyrins are described. Their spectroscopic characterizations are presented in comparison with the permethyl derivatives of porphyrin, sapphyrin and hexaphyrin. The ethoxycarbonyl containing pentaphyrins are the only examples, amongst the expanded polypyrrolic macrocycles, that have an electron withdrawing group directly attached to the macrocyclic ring system. Elimination of a pyrrole and methine carbon unit in the mass spectrometer has been observed as a common feature for the pentaphyrin free bases as well as their metal derivatives.
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■ Polycyclic N-Heterocyclic Compounds. 49 New Synthetic Method of Furo[3,2-f][1,7]naphthyridine Skeleton
Takashi Hirota,* Tetsuo Matsushita, Kenji Sasaki, and Setsuo Kashino
*Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Okayama, 700, Japan
Abstract
An synthesis of 5-amino-1,2-dihydrofuro[3,2-f][1,7]naphthyridine (6) from 3-(3-cyanopropoxy)pyridine-2-carbonitrile (5) is described. Compound (6) was converted to mother skeleton (12). Treatment of 6 with conc. hydrochloric acid gave new spiroheterocycle (7).
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■ Structural and Conformational Analysis of Naturally Occurring Cularine N-Oxide Alkaloids
Rafael Suau,* Rafael Garcia Segura, M. Victoria Silva, Maria Valpuesta, Domingo Dominguez, and Luis Castedo
*Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Málaga, E-29071 Málaga, Spain
Abstract
(+)-cis- and (+)-trans-Cularidine N-oxides were isolated from Ceratocapnos heterocarpa. Their structures and conformations were derived from 1H, 13C, one dimensional nOe nmr data and their chemical behaviour. The trans isomer possesses the usual conformation of cularine alkaloids and readily undergoes Cope elimination. The cis isomer exhibits a different conformation at the dihydroxepine ring.
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■ Silver Catalyzed Cyclization of Alkynoic Acids: Efficient Synthesis of 3-Alkylidenephthalides, γ -Alkylidenebutenolides, and γ-Alkylidenebutyrolactones
Yoshimitsu Ogawa, Masao Maruno, and Takeshi Wakamatsu*
*Central Research Laboratories, Tsumura & Co., 3586 Yoshiwara, Ami-machi, Inashiki-gun, Ibaraki 300-11, Japan
Abstract
The cyclization of 2-pentynylbenzoic acid (1a) catalyzed by various silver salts and solvents was investigated. 2-Alkynylbenzoic acids (1), 2-alken-4-ynoic acids (7), and 4-alkynoic acids (4) were effectively cyclized to the corresponding phthalides (2), γ-alkylidenebutenolides (8), and γ-alkylidenebutyrolactones (5) with silver iodide or silver as catalyst in DMF regio- and stereo-selectively in excellent yield, respectively.