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. 27, No. 2, 1988
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■ Novel Cyclization of Ethyl 2-Bromopyruvate with Dialkylthioamides of N-Protected Amino Acids: One Pot Synthesis of 1,2,3,5-Tetrasubstituted Pyrroles
Tarek S. Mansour* and Gilles Sauvé
*Biochemical Products Division, Institut Armand-Frappier, Université du Québec, 531 Boulevard de Prairies, Laval, Québec, H7V 1B7, Canada
Abstract
Reaction of ethyl 2-bromopyruvate (1) with various N-t-Boc, N-ethoxycarbonyl or N-acetyl phenylalanine or methionine dialkylthioamides under sulfur extrusion conditions gave 1,2,3,5-tetrasubstituted pyrroles in good yields.
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■ Aminolysis of Halogenopyridines at High Pressures
Shiro Hashimoto, Shinichi Otani, Tadashi Okamoto, and Kiyoshi Matsumoto*
*College of Liberal Arts and Science, Kyoto University, Yoshida, Sakyou-ku, Kyoto 606-8501, Japan
Abstract
The transformation of some halogenopyridines to the corresponding aminopyridines has been realized in moderate to excellent yields at high pressures of 6~8 kbar.
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■ 3-Acyl-2-(N-cyanoimino)thiazolidines as an Acylation Agent. Preparation of Amides, Esters, and Thioesters
Chuzo Iwata,* Mayumi Watanabe, Shigeha Okamoto, Michitaro Fujimoto, Masatoshi Sakae, Masanori Katsurada, and Takeshi Imanishi
*Faculty of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Toyonaka, Osaka 560-0043, Japan
Abstract
3-Acyl-2-(N-cyanoimino)thiazolidines proved to be powerful acylating agents. They reacted easily with amines, alcohols, and thiols to give the corresponding amides, esters, and thioesters in good yields.
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■ A Chiral Synthesis of the Key Intermediate of 1β-Methylcarbapenem Antibiotic
Masataka Ihara, Masanobu Takahashi, Keiichiro Fukumoto,* and Tetsuji Kametani
*Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
The synthetic intermediate, (-)-(3S,4R)-3-[(1R)-1-t- butyldimethylsilyloxyethyl]-4-[(1R)-l-hydroxymethylethyl]azetidin-2-one (2), of 1β -methylcarbapenem antibiotic was synthesized from (S)-methyl 3-hydroxy-2-methylpropionate through the intermolecular nitrone 1,3-dipolor cycloaddition.
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■ Chemical Studies on the Transformation of Penicillins - I: Synthesis of Cyclic Disulfides and Thiosulfinates Related to Asparagusic Acid
Ching-Pong Mak* and Gerhard Schulz
*Sandoz Forschungsinstitut, 1235 Wien, Brunnerstraße 59, Austria
Abstract
The synthesis of cyclic disulfides and thiosulfinates related to Asparagusic acid from penicillin sulfoxides are described.
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■ Three New C19-Diterpenoid Alkaloids from Delphinium occidentale S. Wats.
Palaniappan Kulanthaivel, S. William Pelletier,* and John D. Olsen
*Department of Chemistry, Institute for Natural Products Research, The University of Georgia, Chemistry Building, Athens, Georgia 30602-2556, U.S.A.
Abstract
Three new C19-diterpenoid alakaloids have barn isotated from Delphinium occidental S. wats.: occidentaline (16), occidentalidine (17) and 6-acetyldelpheline (18). Structures were deduced by spepctroscopic methods and chemical correlations. Twelve known C19- and two C20-diterpenoid alkaloids were also isolated.
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■ New Method and Reagents in Organic Synthesis. 74. Lithium Trimethylsilydiazomethane. A Useful Reagent for the Preparation of Pyrazoles from α,β-Unsaturated Sulfones
Tetsuo Asaki, Toyohiko Aoyama, and Takayuki Shioiri*
*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
Abstract
Lithium trimathylsilyldiazomethane smoothly reacts with various α,β-unsaturated sulfones to give 3 (or 5)-trimethylsilylpyrazoles in excellent yields.
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■ Intramolecular Cyclization of Purine Nucleosides by N-Halogenosuccinimides/Acetic Acid. A Mechanistic Aspect on the C(8)-Halogenation of Purine Nucleosides
Yoshifumi Maki,* Magoichi Sako, Takao Saito, and Kosaku Hirota
*Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan
Abstract
Upon treatment with N-halogenosuccinimides in acetic acid, 2’,3’-O-isopropylidene purine nucleosides (1) undergo an intramolecular cyclization leading to the corresponding 5’-O,8-cyclopurine nucleosides (2), which strongly suggests that the initial attack of a halogenium ion occurs at the N(7)-position rather than the C(8)-position in the purine ring under the conditions employed.
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■ Enantiomeric Resolution of 3,5’-Dimethyl-4,4’-dibromo-1,1’-bispyrazolylphenylmethane by Liquid Chromatography on Triacetylcellilose
Paloma Ballesteros,* Rosa M. Claramunt, José Elguero, M. del Carmen L. Gallego-Preciado, Chiritian Roussel, and Ahmed Chemlal
*Departomento de Química Organí, UNED, e Instituto de Química , C.S.I.C. / Universidad Complutanse de Madrid, Ciudad Univetsitaria, 28049 Madrid, Spain
Abstract
The experimental conditions to determine the optical purity of the title compound 1 have been found studying the effect of lanthanide shift reagents (LSR), Eu (fod)3 and Eu (tfc)3 The obtention of enriched enantiomers (57.5%) in (+)-1 and 62% in (-)-1) was possible by the use of liquid chromatography arer triacety.Lcellulose. The compound was devoid of any significant antifungal activitly.
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■ Cyclic Acylimines. I. Synthesis and Reactivity of Isoquinoline-1,4-diones
Ignacio J. Alonso-Silva, Mercedes Pardo, and José L. Soto*
*Departamento de Química Orgánica, Facultad de Química, Universidad Complutense de Madridas, Ciudad Universitaria, E-28040 Madrid, Spain
Abstract
3-Methoxycarbonylisoquinoline-1,4-dione (1) has been prepared through elimination processes from appropriate starting materials. The quinome was trapped by cycloaddition reactions with conjugated dienes. High regioselectivity was observed. A similar approach to prepare 3-benzoylisoquinoline-1,4-dione (2) was unsuccessful.
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■ Pseudoesters and Derivatives. XXVII. Thermolysis and Photolysis of Cyclozdducts of Diazomethane with 5-Methoxy-3-pyrrolin-2-ones. Formation of 4-Alkyl-3-pyrrolin-2-ones and 3-Azabicyclo[3.1.0]hexan-2-ones
Francisco Fariña, M. Victoria Martín, M. Carmen Paredes, and Ameria Tito
*Instituto de Química Orgánica General, C. S. I. C., Calle Juan de Cierva, 3, 28006 Madrid, Spain
Abstract
Thermal decomposition of the cycloadducts 2a,b and 2’a leads to 4-methyl substituted pyrrolinones 4a,b as the main products, along with minor amounts of the corresponding cyclopropane derivative 3a,b and 3’a respectively. However, by thermolysis of 2’b and photolysis of 2a,b and 2’a,b the proportions of the products are reversed, the cyclopropane derivative of the type 3 being the major component. The formation of the cyclopropane derivative by both thermolysis and photolysis of the cycloadducts 2 proceeds with retention of stereochemistry.
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■ The Nitration of Some Phenyl-substituted N-Heterocycles
Derek T. Hurst*
*School of Analytical and Biological Chemistry, Kingston Polytechnic, Kingston-on-Thames, KT1 2EE, U.K.
Abstract
The nitration of 3-methyl-1-phenylpyrazole using nitric acid and sulphuric acid at O°C gives the p-nitrophenyl isomer as the only isolated mono nitroproduct and 3-methyl-4-nitro-1-p-nitrophenylpyrazole as the dinitro-product. 3-Methyl- 4-phenylpyrazole gives 3-methyl-4-p-nitrophenylpyrazole with the second nitration also occurring in the phenyl ring to give 3-methyl-4-(2’,4’-dinitrophenyl)pyrazole. 2-Phenylimidazole nitrates under these conditions to give first 2-p-nitrophenylimidazole and then 4-nitro-2-p-nitrophenylimidazole whilst 4-phenylimidazole gives 4-nitro-5-p-nitrophenylimidazole readily even when the amount of nitric acid is limited to one equivalent and only traces of a mono nitro-product are found. 2-Phenylimidazoline gives solely the m-nitrophenyl isomer under the same conditions. The mixed acid nitration at 0°C of 4-phenylmorpholine gives 4-m-nitrophenyl- and 4-p-nitrophenylmorpholine in the ratio of about 5:1.
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■ Nmr Studies of Indole
Pedro Joseph-Nathan,* Rosa E. del Río, and Martha S. Morales-Ríos
*Departmento de Química del Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Apartado 14-740, México, D.F., 07000, Mexico
Abstract
Definitive assignment of the 13C-nmr spectra of indole in DMSO-d6 and CDCl3 were obtained by two-dimensional HETCOR spectra combined with homonuclear 1H double resonance measurements. The deuterium/ hydrogen isotope effects on carbon-13 chemical shifts, measured after interchange of the labile proton of indole, are discussed.
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■ An Improved Synthesis of 3-Carbomethoxy-4H-quinolizone via Palladium(II) Assistance
George R. Newkome,* Kevin J. Theriot, Frank R. Fronczek, and Chris C. Casten
*Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803-1804, U.S.A.
Abstract
The synthesis of 3-carbomethoxy-4-quinolizone from 2-vinylpyridine. dimethylmalonate and PdCI2 under mild conditions is described. A mechanism is discussed in which Pd (II) facilitates initial attack by malonate anion on 2-vinylpyridine and then acts as an oxidant to give the final product. When the reaction is conducted in MeCN, a condensation of malonate with MeCN occurs as a competing reaction. X-ray crystal structures of this side product as well as 3-carbomethoxy-4-quinolirone are presented.
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■ Reaction of 2H-1-Benzopyrans with Organometallic Reagents. Synthesis of 4-(α,γ-Dialkyl-β-4-methoxyphenylallyl)resorcins
Angel Alberola,* Celia Andrés, Alfonso González Ortega, Rafael Pedrosa, and Martina Vicente
*Deparamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, 47005 Valladolid, Spain
Abstract
The stereoselective synthesis of E- and Z-4-(α,γ-dialkyl-β-4- methoxyphenylallyl)resorcins was accomplished by reaction of 2-alkyl-7- hydroxy-4’-methoxyisoflavenes with organoaluminum and organomagnesium reagents. This way leads to better yields than the reduction of 2,4-dialkyl- 7-hydroxy-4’-methoxyisoflavenes. The influence of substituents at different positions on the reduction was studied on model 2H-1-benzopyrans.
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■ The Condensation Products of 2-Chloro-3-formylquinolines with o-Aminothiophenol
Ines Torrini, Giampiero Pagani Zecchini, and Mario Paglialunga Paradisi*
*Dipartminto di Studi Farmaceutical, Università a degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 2 - 00185 Roma, Italy
Abstract
2-Chloro-3-formylquinolines 1a-d undergo cyclizatian with ortho-aminothiophenol(2) )in DMF in the presence of potassium carbonate, at room temperature, to afford quino[2,3-b][1,5] benzothiazepines 3a-d. The benzothiazoline 5 or the benzothiazole 6 was instead obtained as the only isolable product when the above reaction was performed on 1b, in the absence of base, in DMF or in THF respectively. The reduction of 3a-c to 11,12-dihydroquino[2,3-b][1,5]benzothiazepines 4a-c is also reported.
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■ Spectral Properties of Ring-C-Oxygenated 4-Azafluorenes and 4-Azafluorenones. The structures of Natural Onychine erivatives
Dragana Tadic, Bruce K. Cassels, and André Cavé
*Faculté de Pharmacie, UA 496 CNRS, 5 rue J.B. Clément, 92296 Châtenay-Malabry Cedex, France
Abstract
4-Azafluorenes bearing a methoxy group at C-5, -6, -7 or -8 and a methyl at C-1 or -3 were synthesized by thermolysis of O-crotyloximes of appropriately substituted ndan-1-ones. The corresponding azafluorenones were prepared, and the methoxy-1-methyl-4-azafluoren-9-one isomers were O-demethylated. The proton nmr, uv-visible and mass spectra of these compounds support the structures assigned to the more complex azafluorenone alkaloids kinabaline, darienine and macondinc, and provide additional guidelines for the structure elucidalion of other natural products belonging to this class.
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■ Studies on the Chemical Tranformations of Rotenoids. III. Ring Conversations of Methyl Rotenononate and β-Rotenonone
Jinsaku Sakakibara,* Shin-ichi Nagai, Teppei Akiyama, Taisei Ueda, Noriichi Oda, and Kiyoshi Kidouchi
*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan
Abstract
Ring conversions of methyl rotenononate (2b) and β-rotenonone (3) into rotenonone (1) or 4H-furo [2,3-h] [1] benzopyrans (5a-b) were investigated. The Beckmann rearrangement of 2b oxime (6) in PPA provided methyl 3-(benzofuran-5-y1)carbonylamino-(9). 3-(benzofuran-5-yl)aminocarbonyl- 2-benzofurancarbccxylate (10) and furo [2,3-g] benzoxazole (11), whereas 3 oxime (12) gave furo [2,3-g] benzoxazole (13) as a single product. Compound 2b-underwent ring closure with hydrazines to provide benzofuro-[2,3-d]pyridazin-4(3H)-ones (14a-e).
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■ Synthesis of Argvalin and Its Related Compound
Akihiro Ohta,* Yutaka Aoyagi, Yohko Kurihara, Akihiko Kojima, Kayo Yuasa, and Makoto Shomazaki
*Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
Abstract
Argvalin (3) and 6-(4-guanidinobutyl)-3-isobutyl-2(1H)-pyrazinone (4) were synthesized from DL-alanyl-valyl anhydride (6) and DL-alanyl-leucyl anhydride (5) respectively.
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■ Biomimetic Total Synthesis of Dracaenone Derivatives
Gábor Blaskó and Geoffrey A. Cordell*
*Program for Collaborative Research in the Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 833 South Wood St., Chicago, IL 60612-7231, U.S.A.
Abstract
(±)-10-Hydroxy-11-methoxy-dracaenone (1) and (±)-7,10-dihydroxy-11-methoxy-dracaenone (2) were synthesized by phenolic oxidative coupling from the hamoisoflavan derivatives 6 and 13, respectively.
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■ Condensed Heteroaromatic Ring Systems. XIV. Cyclization of ortho-Substituted α-Ethoxynnamates to Some Heteroaromatics
Takao Sakamaoto, Yoshinori Kondo, and Hiroshi Yamanaka*
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
The reaction of 2-iodoaniline with ethyl 2-ethoxyacrylate in the presence of palladium-charcoal gave 3-ethoxy-2(1H)-quinolinone, and the reaction of 2-iodoacetanilide with the same reagent yielded ethyl 2-acetylamino-α-ethoxycinnamate which was cyclized to ethyl indole-2-carboxylate under acidic conditions. On the other hand, the palladium-catalyzed reaction of 2-iodobenzonitrile and ethyl 2-iodobenzoate afforded the corresponding cinnamates which were transformed into isoquinoline and isocoumarin derivatives.
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■ Syntheses of α,β-Unsaturated Ketones Starting from Vinylic and Allylic Grignard Reagents via 2-Imidazolylmethanol Intermediates
Satoshi Hayakawa, Tohru Michiue, Masao Okamoto,* Shoko Hatakeyama, and Shunsaku Ohta
*Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8412, Japan
Abstract
Various α , β -unsaturated ketones (9,12 and 16) were prepared from 2-alkanol-1-methyl-1H-imidazoles (6,10 and 13 respectively), which were obtained by treatment of 2-acyl-lmethyl-lH-imidazoles (1) with vinylic Grignard reagents, a lithium acetylide and allylic Grignard reagents, respectively. dl-(ar)-Turmerone (16i) was also synthesized as an application of the present methodology.
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■ Synthesis of 13-Methyl[10](4,6)pyrimidinophane
Takao Sakamoto, Sumiko Nishimura, Yoshinori Kondo, and Hiroshi Yamanaka*
*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan
Abstract
The palladlium-catalyzed reaction of 4,6-diiodo-2-methylpyrimidine with 5-trimethylsilylpent-4-yn-1-ylzinc iodide gave 4,6-bis(5-trimethylsi1ylpent-4-yn-1-yl)-2-methylpyrimidine. Desilylation of the product followed by treatment with cupric acetate gave 13-methyl[10](4,6)pyrimidinophane.
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■ Reactions with Cyclic Oxalyl Compounds, Part 26: The Fischer-Indole Rearrangement of Sterically Hindered Systems Part 7: Diaza[n.3.3]propellanes via Thermally Initiated Fischer-Indolization
Gert Kollenz, Ralph Theuer, Walter Ott, Karl Peters, Eva-Maria Peters, and Hans Georg von Schnering
*Max-Planck-Institut für Festkörperforachung , Heisenbergstrasse 1. D-7000 Stuttgart 80, Germany
Abstract
The 4,5-bridged pyrrol-2,3-diones 3, obtained from cyclocondensation reactions of the N,N-disubstituted hydrazones 2 and oxalyl dichloride, can be rearranged into the corresponding diaza[n.3.3]propellanes 4 via a thermally initiated Fischer - indolization process. Their molecular structure is confirmed with aid of an X-ray structure determination of 4a and chemical degradation reactions leading to the tetracyclic indole systems 5.
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■ Synthetic Studies towards (—)-Quassimarin: An Intramolecular Diels-Alder Approach to the BDE Ring System
Kozo Shishido, Kazuyuki Takahashi, Yoshihisa Oshio, Keiichiro Fukumoto,* Tetsuji Kametani, and Toshio Honda
*Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
A novel and a chiral approach to the synthesis of BCE ring system of (-)-quassimarin is described which involves an intramolecular Diels-Alder reaction of the trienic precursor (18) as a key step. The key dihydrofuranone (17) was prepared from L-(+)-diethyl tartrate via 14 step sequence. The quaternary carbon centre in (17) was stereoselectively constructed by magnesium chelation controlled addition of α-lithio- α-methoxyallene to α, β-dialkoxy ketone. Thermolysis of the triene (18) and subsequent hydrolysis provided two tricyclic cycloadducts (19) and (20), both structures were characterized spectroscopically as the corresponding acetates (21) and (22). Particularly, the major adduct (21) was established by the X-ray crystallographic analysis.
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■ Prganic Nitrosonium Salts as Oxidants in Organic Chemistry
James M. Bobbitt and Cecil L. Flores
*Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, U.S.A.
Abstract
The synthesis of stable nitrosonium salts end their use as oxidizing agents in organic chemistry will be summarized. Thoes systems in which nitroxides are oxidized to nitrosonium salts which, in turn. Function as oxidants (mediated systems) will also be discussed. Nitrosonilum salts can be used to oxidize alcohols (to aldehydes or ketones), primary amines (to aldehydes, or in certain case=, RCH2NH2, to nitriles), ketones (to α-diketones), and phenols (to quinones). Some dehydrogenations are also known, as well as other miscellaneous reactions.