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. 9, No. 2, 1978
Published online:
■ Two New Sesquiterpenoids from Chloranthus glaber Makino
Masaaki Uchida, Genjiro Kusano, Yoshikazu Kondo, Shigeo Nozoe,* and Tsunematsu Takemoto
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
Two new sesquiterpenes, chloranthalactone A (I) and B (II) were isolated from Chloranthus glaber Makino and characterized.
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■ The Methylene Signature of Reduced Isoquinolines: A PMR Structural Correlation
Jerome L. Moniot and Maurice Shamma*
*Department of Chemistry, The Pennsylvania State University, York Campus, P1031 Edgecomb Avenue, York, Pennsylvania 17403, U.S.A.
Abstract
The ring B methylene proton signals in the pmr spectra of reduced isoquinolines appear as symmetrical triplets when nitrogen inversion is precluded, and as complex multiplets when the nitrogen atom can undergo inversion. The chemical shifts for the ring B protons on the carbon adjacent to nitrogen are dependent on the state of that nitrogen atom, and are in the following order of increasing δ values: Amines
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■ Cycloaddition of 2-Phenyl-3-ethoxycarbonyl-Δ2-pyrroline-4,5-dione to Cyclopentadiene
Yoshisuke Tsuda,* Miyuki Kaneda, Yoshitaka Itatani, Takehiro Sano, Yoshie Horiguchi, and Yoichi Iitaka
*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan
Abstract
Cycloaddition of 2-phenyl-3-ethoxycarbonyl-Δ2-pyrroline-4,5-dione to cyclopentadiene in either photochemical or thermal condition gave three products: the dihydropyridone (A), the cyclobutane (B), and the bicycloheptane (C), the structures of which were established by spectroscopic means and by X-ray analyses of their bromo-derivatives. A possible mechanitic rationalization would involve [2a+2s] cycloaddition governed by donor-acceptor interaction followed by cleavage and recombination of a trans-fused cyclobutane.
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■ A New Route to 3,4-Dihydro-2-pyridones from a Dioxopyrroline Derivative
Takehiro Sano,* Yoshie Horiguchi, Yoshisuke Tsuda,* and Yoshitaka Itatani
*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan
Abstract
In photocycloaddition of 2-phenyl-3-ethoxycarbonyl-Δ2-pyrroline-4,5-dione to olefins, the formation of dihydropyridones were observed although the yields were variable depending on the structure of olefins.
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■ Reaction of 1-Phenyl-4-hydrazino-4,5-dihydro-6H-furo[2,3-d][1]benzazepine-5-carboxylic Acid Hydrazide with Aromatic Aldehydes
Kazuo Ito, Kenichi Yakushijin, and Shigetaka Yoshina*
*Faculty of Pharmacy, Meijo University, 150 Yagoto, Tempaku-ku, Nagoya, Aichi 468-8503, Japan
Abstract
l-Phenyl-4-hydrazino-4,5-dihydro-6H-furo[2,3-d][1]benzazepine-5-carboxylic acid hydrazide (2) reacts with aromatic aldehydes in ethanol to give saturated monoarylylidene compounds (3a-c) and unsaturated monoarylylidene compounds (5a-c), respectively.
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■ Synthesis of the Antibiotic, (±)-Pyridindolol
Geng Wu, Etsuji Yamanaka, and James M. Cook*
*Department of Chemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, U.S.A.
Abstract
Pictet-Spengler condensation of tryptophan methyl ester 7 with glyceraldehyde acetonide 8 in refluxing benzene provided the 1,2,3,4-tetrahydro β-carboline 9 in good yield. The β-carboline was then converted in three steps to the β-galactosidase inhibitor, pyridindolol 1.
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■ 1,3-Oxazines and Related Compounds. III. Ring Contraction Reaction of 1,3-Oxazin-4-one Derivatives into 1,2,4-Oxadiazoles and Isoxazoles
Yutaka Yamamoto* and Yutaka Azuma
*Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan
Abstract
Reaction of 2-phenyl-, 2-(2-pyridyl)-, 2-(3-pyridyl)- and 2-(2-quinolyl)-6-methyl-4H-1,3-oxazin-4-one (1a-d) with hydroxylamine hydrochloride in the presence of sodium acetate or sodium alkoxide led to a formation of the corresponding 1,2,4-oxadiazoles 4a-d in 72%, 65%, 80%, and 71% yield, respectively.
On the other hand, treatment of 1a-d with hydroxylamine hydrochloride in 95% ethanol gave rise to the corresponding isoxazoles 7a-d.
Analogously, the 2,3-dihydro-1,3-oxazine 1e underwent the ring contraction into the 1,2,4-oxadiazole 4e and isoxazole 7e in 32% and 56% yield, respectively.
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■ Synthesis of the Alkaloid Haplobucharine
Pietro Venturella* and Aurora Bellino
*Dipartimento di Chimica Organica, Università digli Studi di Palermo, Via Archirafi 20 90123 Palermo, Italy
Abstract
A simple synthesis of haplobucharine [I], an alkaloid isolated from Haplophillum bucharicum was described.
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■ Reaction of 6-Amino-1,3-Dimethyluracils with Ethoxymethylenemalononitrile
Katsuhiko Nagahara* and Atsushi Takada
*School of Pharmaceutical Sciences, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
Abstract
Treatment of 6-amino-1,3-dimethyluracil with ethoxymethylenemalononitrile (EMMN) afforded 1,3,7,9-tetramethylpyrido[2,3-d:6,5-d’]dipyrimidine-2,4,6,8-(1H,3H,7H,9H)-tetrone and 7-amino-6-cyano-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione. On the other hand, reaction of 6-hydrazino-1,3-dimethyluracil with EMMN gave 6-(3-amino-4-cyanopyrazol-2-yl)-1,3-dimethyluracil.
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■ Studies on ths Synthesis of Bisindole Alkaloid. XII. Derivatives of Vincristine
James P. Kutney,* John Balsevich, Toshio Honda, Ping-Huang Liao, Herman P. M. Thiellier, and Brian R. Worth
*Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, B.C. V6T 1Z1, Canada
Abstract
Specific Jones’oxidation of 3’,4’-dehydrovinblastine, leurosine, 19’-oxoleurosine, 6,7-dihydra-4’-deoxyleurosidine and 3’,4’-dehydro-3-desvarbomethoxy-3-N-methylcarboxamldovinblastine provided the corresponding 22-oxo-derivatives of the vincristine series. Further oxidation of 22-oxoleurosine, with iodine/sodium bicarbonate, gave the 19’-oxo-bisindole.
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■ A Base-catalyzed Oxygenation of the β-Apolignan: A Biogenetic Model
Takefumi Momose* and Ken-ichi Kanai
*Faculty of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Toyonaka, Osaka 560-0043, Japan
Abstract
A biogenetic-type transformation of the β-apolignan (I) into naphthalide lignans (II and III) by a base-catalyzed oxygenation is described.