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. 55, No. 10, 2001
Published online:
■ Synthesis of (-)-Idiadione, a Furanosesterterpene Isolated from a Marine Sponge Spongia idia
Yoshihiro Noda,* Hiroyuki Hashimoto, and Toshie Norizuki
*Department of Materials Chemistry and Engineering, College of Engineering, Nihon University, Tamura-machi, Koriyama, Fukushima, 963-8642, Japan
Abstract
(-)-Idiadione (1), a furanosesterterpene isolated from a marine sponge Spongia idia, was synthesized, starting from (S)-(-)-citronellal (2). The absolute configuration of naturally occurring 1 is established as (S).
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■ A1,3-Dipolar Cycloadditions of New Mesoionic Compounds. Synthesis of 1H-Pyrrolo[1,2-c]thiazoles, Pyrrolizines and 5,6,7,8-Tetrahydroindolizines
Piero Dalla Croce and Concetta La Rosa*
*Istituto di Chimica Organica, Facoltà di Farmacia, Università degli Studi di Milano, Via Venezian 21, I-20133 Milano, Italy
Abstract
We studied the 1,3-dipolar cycloaddition reactions between alkyne dipolarophiles and the new mesoionic compounds 2H,5H,7H-thiazolo[4,3-b]oxazol-2-one (12), 2H,5H,7H-pyrrolo[2,1-b]oxazol-2-one (13) and 2H,5H,7H-oxazolo[3,2-a]pyridin-2-one (14). These 1,3-dipoles were prepared in situ by means of cyclodehydration with acetic anhydride of the corresponding α-substituted 4-oxo-3-thiazolidine- (9), 2-oxo-1-pyrrolidine- (10) and 2-oxo-1-piperidineacetic acids (11). The cycloaddition reactions with alkyne dipolarophiles afforded single 1H-pyrrolo[1,2-c]thiazole, pyrrolizine and 5,6,7,8-tetrahydroindolizine derivatives, or a mixture of the two possible regioisomers, depending on whether symmetrical or unsymmetrical alkynes.
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■ Thermal Rearrangements of 3,3-Spiroalkylated Pyrazoles: Ring Expansion and Novel Cases of Sequential 1,5-Shifts
Yao-pin Yen,* Shih-Feng Chen, Zan-Cheng Heng, Jen-Chieh Huang, Li-Chun Kao, Ching-Cheng Lai, and R. S. H. Liu
*Department of Applied Chemistry, Providence University, 200 Chungchi Road, Sha-Lu, Taichung Hsien, 433, Taiwan, R.O.C.
Abstract
A 3,3-spiro-(cyclopentyl)pyrazole containing electron withdrawing ester groups undergoes readily ring expansion in the form of the van Alphen- Huettel rearrangement. Subsequent post van Alphen-Huettel rearrangement involved a sequence of 1,5-shifts different from that suggested earlier. Reactive intermediates have been isolated and identified. The corresponding phenyl analog does not exhibit post van Alphen-Huettel rearrangement. A rationale for the different behavior is offered. X-Ray crystallography has been applied to differentiate between structurally similar product.
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■ Regioselective Formylation of Ethyl 3,4-Dihydro-2H-1,4- benzoxazine-2-carboxylate or 2-Acetate Derivatives
Stanislas Mayer, Gérald Guillaumet, and Jean-Yves Mérour*
*Institut de Chimie Organique et Analytique, UMR CNRS 6005, BP 6759, Université d'Orléans, Rue de Chartres, 45067 Orléans Cédex 2, France
Abstract
Formylation reactions on ethyl 3,4-dihydro-2H-1,4-benzoxazine-2-carboxylate or 2-acetate derivatives were carried out using either Vilsmeier-Haack’s conditions or Rieche’s method. 7-Formyl compounds were exclusively obtained from N-benzyl-3,4-dihydro-2H-1,4-benzoxazines derivatives through Vilsmeier’s procedure. A mixture of 6- and 8-formyl compounds, where the isomer in position-6 was predominant, was formed using the Rieche’s method.
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■ Observation of the Primary Intermediates in the Photochemistry of o-Vinylstyrylfurans
Irena Skoric, Nikola Basaric, Zeljko Marinic, and Marija Sindler-Kulyk*
*Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulicev trg 20, P.O Box 177, HR-10000 Zagreb, Croatia
Abstract
The intermediates, 3a,9-dihydro-4,9-methano-4H-benzo[4,5]cyclohepta[1,2-b]furan (3a) and 5b,11-dihydro-6,11-methano-6H-benzo[4,5]cyclohepta[1,2-b]benzo[d]furan (3b), formed upon irradiation of 2-[2-(2-vinylphenyl)ethenyl]furan (1a) and 2-[2-(2-vinylphenyl)ethenyl]benzo[b]furan (1b), respectively, are determined and spectroscopycally characterized. Whereas only the intermediate (3b) reacts photochemically with methanol to give the regioselective adduct (6b), both intermediates are trapped by molecular oxygen giving hydroproxides (7a,b), hydroxy- (8a,b) and keto derivatives (9a, b).
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■ Synthesis of 3-Aryl-7-diethylaminocoumarin Derivatives: Reaction with Isatin and Their Fluorescent Properties
Naozumi Nishizono,* Kazuaki Oda, Kosei Ohno, Masaru Minami, and Minoru Machida*
*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan
Abstract
Fluorescent derivatization reagent, 3-aryl-7-diethylaminocoumarin derivative was synthesized and reacted with isatin. The fluorescent properties were described.
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■ Synthesis of 4(5)-(α-D-Xylofuranosyl)imidazole Starting from L-Arabinose: Mitsunobu Cyclization via C4’-Oxyphosphonium Intermediate
Lisa Araki, Shinya Harusawa, Mayuko Fukuda, and Takushi Kurihara*
*Faculty of Pharmaceutical Science, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
Abstract
4(5)-(a-D-Xylofuranosyl)imidazole (3) was synthesized using Mitsunobu cyclization via C4’-oxyphosphonium intermediate (5) starting from L-arabinose.
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■ Heterocyclization of 4-Trifluoroacetyl-1,3-oxazolium-5-olates with 1,4-Bis-nucleophiles
Masami Kawase,* Hiromi Koiwai, Toru Tanaka, Satoru Tani, and Hiroshi Miyamae
*Josai University, Faculty of Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences1-1 Keyakidai, Sakado, Saitama 350-0295, Japana
Abstract
Reactions of aromatic 1,4-bis -nucleophiles such as o-phenylenediamine and o-aminothiophenol, with mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (1) gave regiospecifically seven member trifluoromethylated heterocycles such as 1,5-benzodiazepines (3) and 1,5-benzothiazepines (4). The reaction with o-aminophenol afforded non-cyclized products (5). The structures of 3, 4, and 5 were established by X-Ray diffraction analysis.
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■ Nucleophilic Substitution Reactions of 4,5-Dichloro-2-methyl-6-nitro-2H-pyridazin-3-one
Kyu-Tae Chang, Jeum-Jong Kim, Young-Kook Kim, Ho-Yong Park, Byung-Hwa Hyun, Motoo Shiro, Yong-Jin Yoon, and Woo Song Lee*
*Department of Chemistry, Korea Advanced Institute of Science and Technology, 373-1, Kusung-Dong, Yusung-Gu, Taejon, 305-701, Korea
Abstract
4,5-Dichloro-2-methyl-6-nitro-2H-pyridazin-3-one (1) reacts with various substituted phenols and 2-mercaptopyrimidine in the presence of NaH or K2CO3 to give 3(2H)-pyridazinones (4, 5a-9a, 5b-9b, and 7c) in high yields. The regiochemistry was confirmed by X-Ray analysis and nOe experiments.
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■ 2-Arylsulfinylmethyloxazines: Chiral Carbonyl Equivalents
Kamaljit Singh,* Prasant K. Deb, and Sonia Behal
*Department of Applied Chemical Sciences & Technology, Guru Nanak Dev University, Amritsar 143 005, India
Abstract
A single pot acid catalysed condensation reaction of 2-arylsulfinylmethyloxazinane – a chiral carbonyl equivalent (derived from the title oxazine by BH4- reduction) with tryptamine and tryptophan esters, furnishes tetrahydro-β-carbolines and can be subsequently transformed into indole alkaloids.
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■ Cucubalactam and Brachystemin E, Two New Compounds from Caryophyllaceae
Yong-Xian Cheng, Jun Zhou,* Ning-Hua Tan, Yang Lu, Xu-Ying Liu, and Qi-Tai Zheng
*Laboratory of Phytochemistry, Kunming Institute of Botany, The Chinese Academy of Sciences, Heilongtan, Kunming 650204, China
Abstract
A new pyrrolidone peroxide, named cucubalactam (1), and a new octacyclopeptide, named brachystemin E (2), have been isolated from Caryophyllaceae plants, Cucubalus baccifer and Brachystemma calycinum, respectively. Their structures were determined by spectral methods, especially by 1D and 2D NMR techniques. The stereochemistry of compound (2) was demonstrated by X-Ray crystallograph.
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■ New Flavonoid from Mentha longifolia
Nusrat Jahan, Abdul Malik,* and Pir Muhammad
*International Centre for Chemical Sciences, H. E. J. Research Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan
Abstract
5,8,4’-Trihydroxy-6,7,3`-trimethoxyflavone (1) was isolated from Mentha longifolia, along with three known compounds(2-4). The structure of 1 was established through the extensive spectroscopic studies including 2D-NMR.
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■ A Convenient Samarium-induced Reduction of Ferrocenyl Imines
Susanta Samajdar, Anjan Ghatak, Frederick F. Becker, and Bimal K. Banik*
*Department of Molecular Pathology, Box 89, MD Anderson Cancer Center, The University of Texas, 1515 Holcombe Boulevard, Houston, Texas 77030, U.S.A.
Abstract
Samarium metal induced reduction of the ferrocenyl imines to the ferrocenyl amines in excellent yield has been developed.
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■ Synthesis of 1,2,4-Oxadiazolylimidazo[1,5-a]thieno[2,3-e]pyrazines as Ligands for the γ-Aminobutyric Acid A/Benzodiazepine Receptor Complex
Thomas Erker* and Karin Trinkl
*Institute of Pharmaceutical Chemistry, University of Vienna, Pharmaziezentrum, Althanstrsse 14, A-1090 Vienna, Austria
Abstract
Starting from 5-benzoyl-2-chloro-3-nitrothiophene the thieno[2,3-b]pyrazine-2,3-dione ring system (4) was synthesized. This compound was reacted with potassium tert-butoxide and diethyl chlorophosphate to give diethyl 7-benzoyl-4-isopropyl-3-oxo-3,4-dihydrothieno[2,3-b]pyrazin-2-ylphosphate (5), which gave with the desired 5-alkyl-3-isocyanomethyl-1,2,4-oxadiazoles in the presence of additional potassium tert-butoxide the 1,2,4-oxadiazolylimidazo[1,5-a]thieno[2,3-e]pyrazine derivatives (6-10) as ligands for the γ-aminobutyric acid A / benzodiaz-epine receptor complex.
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■ Quinoline Ring Formation by Cycloaddition of N-Arylketenimines with Enol Ethers under High Pressure
Masao Shimizu,* Akihiro Oishi, Yoichi Taguchi, Tomohumi Sano, Yasuo Gama, and Isao Shibuya
*National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
Abstract
The reaction of N-aryl substituted ketenimines with enol ethers under 800 MPa gave quinoline derivatives, which formed by cyclization between the C=C-N=C aza-diene moieties of N-aryl substituted ketenimines and the C=C double bond moieties of enol ethers. When cyclic enol ethers such as 2,3-dihydrofurans or 3,4-dihydro-2H-pyrans were used as dienophiles, quinoline derivatives that had substituents with hydroxyalkyl or oxoalkyl side chains on the C-3 positions were synthesized in one step reaction.
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■ A Modified Niementowski Reaction for the Synthesis of 4-Hydroxyquinoline and Its Related Compounds
Jae Keun Son, Seung Ill Kim, and Yurngdong Jahng*
*College of Pharmacy, Yeungnam University, Kyongsan 712-749
, Korea
Abstract
The iminoketene generated from anthranilic acid and thionyl chloride reacted with ketones to afford 4-hydroxyquinoline derivatives in good yields.
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■ Regioselective Intramolecular Cycloaddition of C-(1-Acryloyl-2-pyrrolyl)-N-benzylnitrone: Entry to 6-Hydroxy-5-oxoindolizidines
Gianluigi Broggini,* Tullio Pilati, Alberto Terraneo, and Gaetano Zecchi
*Dipartimento di Scienze Chimiche, Fisiche e Matematiche, Università dell’Insubria, via Valleggio 11, 22100 Como, Italy
Abstract
The title nitrone underwent intramolecular cycloaddition in regioselective and stereoselective manner, giving one bridged-ring cycloadduct (4). Further elaboration of the latter led to 6-hydroxy-5-oxoindolizidine derivatives (5) and (6), which can be seen as useful intermediates in alkaloids synthesis.