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. 63, No. 11, 2004
Published online: 1st October, 2004
■ Synthesis of 4-Methoxybenzylamino Derivatives of Dibenzothiadiazepinedioxide
Nicolas Lebegue,* Sebastien Gallet, Nathalie Flouquet, Pascal Carato, Stéphanie Giraudet, and Pascal Berthelot
*Laboratoire de Chimie Thérapeutique, Faculté des Sciences Pharmaceutiques et Biologiques de Lille, Université de Lille 2, 3, rue du Professeur Laguesse, BP 83, F-59006 Lille, France
Abstract
This article reports the synthesis of new dibenzothiadiazepinedioxides bearing a 4-methoxybenzylamino group at 8- or 9-C position of the tricyclic heterocycle. Construction of the 8- or 9-aminodibenzothiadiazepinedioxide is achieved via Weber’s method and the 4-methoxybenzyl analogues are realized by reductive amination using 4-anisaldehyde.
Published online: 17th September, 2004
■ A Xanthone-based Macrocyclic Receptor and Its Possible Applications
José V. Hernández, Ana I. Oliva, Francisco M. Muñiz, Luis Simón, César Raposo, and Joaquín R. Morán*
*Department of Organic Chemistry, University of Salamanca, Plaza de los Caídos, 1-5, Salamanca, E-37008, Spain
Abstract
A macrocycle (2) based on xanthone units and diphenylethylenediamine is shown to present strong affinity for chloride ion; the extraction of sodium chloride from water to chloroform is possible in the presence of (2) and 18-crown-6 ether. Carboxylates also show strong affinities for (2) in MeOH, but no significant chiral recognition was detected for either naproxenate or ibuprofenate. Zwitterionic amino acids are also extracted from water to chloroform in the presence of 18-crown-6 ether. A modest degree of chiral discrimination was observed for phenylalanine, phenylglycine and t-leucine.
Published online: 7th September, 2004
■ Mononuclear Heterocyclic Rearrangement: Synthesis of [5:5] Bicyclic [c]-Fused 3-Aminopyrazoles via the N-N Bond Formation Strategy
David A. Berry, Tun-Cheng Chien, and Leroy B. Townsend*
*Department of Medical Chemistry, College of Pharmacy, University of Michigan, 930 North University, Ann Arbor, MI 48109-1055, U.S.A.
Abstract
The formation of [5:5] bicyclic heterocyclic ring systems containing [c]pyrazoles, i.e. imidazo[4,5-c]pyrazole, pyrazolo[3,4-c]pyrazole, pyrrolo- [2,3-c]pyrazole, and pyrazolo[3,4-d][1,2,3]triazole, was accomplished by mononuclear heterocyclic rearrangement (MHR). The core pyrazole ring was formed based on a N-N bond formation strategy. The ring transformation of 5-substituted 3-(2-aminoaryl)-1,2,4-oxadiazoles (14, 15a-b, 16b and 33) under thermal conditions to the corresponding [5:5] bicyclic [c]-fused 3-aminopyrazole ring systems (17a, 18a-b, 20 and 34 respectively) was promoted by sodium hydride in DMF or DMSO. The ring transformation by MHR has provided a practical and general synthetic method for the derivatives of 3-aminoimidazo- [4,5-c]pyrazole (4), 3-aminopyrazolo[3,4-c]pyrazole (5), 3-aminopyrrolo[2,3-c]- pyrazole (6) and 6-aminopyrazolo[3,4-d][1,2,3]triazole (7).
Published online: 17th September, 2004
■ Synthesis of N-Bridgehead Fused Bicyclic β-Lactams through Organometal-mediated Transformations of 1,2-Dialkenylaziridines
Paolo Davoli, Alberto Spaggiari, Elisa Ciamaroni, Arrigo Forni, Giovanni Torre, and Fabio Prati*
*Dipartimento di Chimica, Università di Modena e Reggio Emilia, via Campi 183, I- 41100 Modena, Italy
Abstract
N-Bridgehead fused bicyclic β-lactams have been synthesized through sequential organometal-mediated transformations of 1,2-dialkenylaziridines, namely Co2(CO)8-catalysed carbonylation and ring-closing metathesis (RCM). When firstly subjected to RCM conditions, either with Schrock-Hoveyda or Grubbs’ catalyst, 1,2-dialkenylaziridines did not afford the expected bicyclic N-bridgehead products. In contrast, however, cis-1,2-dialkenylaziridines were amenable to carbonylative ring expansion, affording trans-1,4-dialkenyl-β-lactams which could be subsequently metathesized to the corresponding fused bicyclic compounds using Grubbs’ catalyst. Unexpectedly, carbonylation of trans-1,2-dialkenylaziridines occurred with the unprecedented rearrangement to the 5,6-dihydro-4H-[1,3]oxazine skeleton.
Published online: 8th September, 2004
■ A General and Efficient Method for Synthesis of Functionalized Ethylenediamine Derivatives
Donghong Li, Junsheng Hao, Wei Guo,* and Chizhong Xia*
*School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
Abstract
Reaction of tetrahydrofolate model, 1-tosyl-3,4-dimethylimidazolinium iodide (1), and a series of aromatic or aliphatic amines produced N,N,N’-trisubstituted-2-methylethylenediamine derivatives (2-10) in good to excellent yields through a nucleophilic addition and the followed ring-opening mechanism. The coenzyme model was proved to be more electrophilic than those reported before.
Published online: 17th September, 2004
■ Synthesis of the Novel Bicyclic Oxepinopyrimidine and Fluorinated Pyrrolidinopyrimidines
Sanja Batinac, Draginja Mrvos Sermek, Mario Cetina, Kresimir Pavelic, Mladen Mintas, and Silvana Raic-Malic*
*Department of Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulicev trg 20, 10000 Zagreb, Croatia
Abstract
The new 5,6-disubstituted pyrimidine nucleoside analogues (5-8) were synthesized by addition of the C-6 lithiated pyrimidine derivative to oxirane as key reaction step. The bicyclic tetrahydrooxepinopyrimidine (9) and fluorinated pyrrolidinopyrimidines (12 and 15) were obtained by intramolecular linkage of acyclic chain to the CH2-5 and N-1 of the pyrimidine ring. The structure of compound (9) containing pyrimidine and tetrahydrooxepine skeleton was determined unequivocally by its X-Ray crystal structure analysis.
Published online: 17th September, 2004
■ The 4-Methoxybenzyl (PMB) Function as a Versatile Protecting Group in the Synthesis of N-Unsubstituted Pyrazolones
Gernot A. Eller and Wolfgang Holzer*
*Institute of Pharmaceutical Chemistry, University of Vienna, Pharmaziezentrum, Althanstraße 14, A-1090 Vienna, Austria
Abstract
Starting from diethyl ethoxymethylenemalonate and 4-methoxybenzylhydrazine (PMB-NHNH2) 2-(4-methoxybenzyl)-2,4-dihydro-3H-pyrazol-3-one was prepared. Reaction of the latter with carboxylic acid chlorides / calcium hydroxide in 1,4-dioxane afforded 4-acyl-5-hydroxy-1-PMB-1H-pyrazoles, whereas with dimethylformamide diethyl acetal or benzaldehyde the corresponding (E)-4-dimethylaminomethylene or (E)-4-benzylidene products, respectively, were obtained. The PMB protecting group could be conveniently removed from the pyrazole nucleus by treatment with trifluoroacetic acid to give the N-unsubstituted pyrazolones. Detailed NMR spectroscopic investigations (1H, 13C, 15N) with the obtained compounds are presented.
Published online: 8th October, 2004
■ 1-Aryl-3-alkyl-1,4,5,6-tetrahydropyrimidinium Salts. Part 2. Reactions with Nucleophiles
María B. García, Mariana Zani, Isabel A. Perillo, and Liliana R. Orelli*
*Departamento de Química Orgánica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 (1113) Buenos Aires, Argentina
Abstract
The reactivity of 1-aryl-3-alkyl-1,4,5,6-tetrahydropyrimidinium salts (1) towards nucleophiles was studied. Hydrolysis of salts (1) afforded initially compounds (2, kinetic products) through the corresponding amidinium hydroxides (4). The regioselectivity of the reaction was analyzed considering the relative leaving group abilities and the stereoelectronic control theory. Amino amides (2a-c) in the reaction medium underwent spontaneous formyl migration, affording compounds (3, thermodynamic products). Reduction of salts (1) with sodium borohydride led to acyclic trimethylenediamines (5) or to the corresponding hexahydropyrimidines (6), according to the reaction conditions. Aminolysis of compound (1f) with isopropylamine yielded an acyclic formamidine (7f).
Published online: 22nd September, 2004
■ New Neolignan and Phenylpropanoid Glycosides in Juniperus communis var. Depressa
Tsutomu Nakanishi, Naoki Iida, Yuka Inatomi, Hiroko Murata, Akira Inada, Jin Murata, Frank A. Lang, Munekazu Iinuma, Toshiyuki Tanaka*
*Gifu Prefectrual Institute of Health and Environmental Sciences, 1-1 Nakafudogaoka, Kakamigahara, Gifu 504-0838, Japan
Abstract
Two new neolignan glucosides (junipercomnosides C and D) and two new phenypropanoid glycosides (junipercomnosides E and F) were isolated from aerial parts of Juniperus communis var. depressa along with seven known phenylpropanoid glycosides. The structures of the isolated compounds were determined by spectral analysis, in particular by the detailed analysis of 2D NMR and CD spectra.
Published online: 22nd September, 2004
■ The Absolute Structures of Dihydroepiheveadride, as Characteristic Antifungal Agent against Filamentous Fungi, and Its Related Compounds from Unidentified Fungus IFM 52672
Tomoo Hosoe, Kazutaka Fukushima, Takeshi Itabashi, Koohei Nozawa, Kayoko Takizawa, and Ken-ichi Kawai*
*Faculty of Pharmaceutical Sciences, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
Abstract
A new nonadride derivative, deoxoepiheveadride (2), was isolated along with dihydroepiheveadride (1), as a characteristic antifungal agent, from unidentified fungus IFM 52672. The absolute structures of 1 and 2 were elucidated by the spectroscopic and chemical investigation. The absolute configuration of heveadride (4), which had been isolated from Bipolaris heveae CBS 241.93, was also determined by X-Ray crystallographic analysis.
Published online: 17th September, 2004
■ Characterization of a 3,4-Dihydro-1,3,4-triphosphacyclopenta[a]indene as an Isomer of a Mes*-substituted 1,3,6-Triphosphafulvene (Mes* = 2,4,6-t-Bu3C6H2)
Shigekazu Ito, Hideaki Miyake, Hiroki Sugiyama, and Masaaki Yoshifuji*
*Department of Chemistry, Graduate School of Science, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan
Abstract
Reaction of 2,2-dibromo-1-(2,4,6-tri-t-butylphenyl)-1-phosphaethene and t-butyllithium gave a 3,4-dihydro-1,3,4-triphosphacyclopenta[a]indene as an isomer of a bulky 1,3,6-triphosphafulvene, which was isolated as a major product in this reaction, and the structure was confirmed by X-Ray analysis. Spectroscopic and redox properties of the 3,4-dihydro-1,3,4-triphosphacyclopenta[a]indene have been studied.
Published online: 7th September, 2004
■ m-Chloroperbenzoic Acid Oxidation of Corynanthe-Type Indole Alkaloid, Mitragynine, Afforded Unusual Dimerization Products
Hayato Ishikawa, Mariko Kitajima, and Hiromitsu Takayama*
*Graduate School of Pharmaceutical Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
Abstract
The m-chloroperbenzoic acid oxidation of a Corynanthe-type indole alkaloid, mitragynine (1), in the presence of trifluoroacetic acid produced unusual dimeric compounds (3 and 4), both of which had a linkage between the C-7 and C-12’ positions in the indole part of the starting material.
Published online: 17th September, 2004
■ Tetrazolium N-Aminides
Dietrich Moderhack* and Matthias Noreiks
*Institut für Pharmazeutische Chemie, Technische Universität, D-38106 Braunschweig, Germany
Abstract
Tetrazolium N-aminides (8-10), i.e. the first derivatives of the types (A-C; Z = NY), have been prepared via the tetrazolium salts (5-7) and fully characterized. The preferred geometries of 8c-10c have been determined by a Hartree-Fock and Density Functional Theory calculation [HF/6-31G(d), B3LYP/6-31G(d)].
Published online: 22nd September, 2004
■ Star-shaped Threefold Dihydropyridine and Xanthene Derivatives
Dirk Sielemann, Andreas Winter, and Nikolaus Risch*
*Chemistry Department, Faculty of Science, Paderborn University, Warburger Str. 100, 33098 Paderborn, Germany
Abstract
Novel star-shaped threefold dihydropyridine (5) and xanthene derivatives (8) have been synthesized using a highly efficient one-pot procedure. Phloroglucinol (1) and Mannich bases (2) have been used as readily available starting materials. The hydrogen bonding in dihydropyridine derivative (5) is characterized by an uncommon high kinetic stability.
Published online: 1st October, 2004
■ A Synthesis of a Novel Heterocyclic System: 2H-Furo[3,2-b][1,4]benzothiazin-2-one
Anton V. Dolzhenko and Wai-Keung Chui*
*Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore 117543, Singapore
Abstract
A synthesis of 3-methyl-2H-furo[3,2-b][1,4]benzothiazin-2-ones (10a,b) is described. o-Aminothiophenols (1a,b) undergo condensation with citraconic anhydride followed by cyclization and oxidation of the resulting 2-(3,4-dihydro-2H-1,4-benzothiazin-2-yl)propanoic acids (5) with thionyl chloride gives moderate yield of 10a,b.
Published online: 10th August, 2004
■ Molecular Rearrangements of 1-Oxa-2-azoles as an Expedient Route to Fluorinated Heterocyclic Compounds
Andrea Pace, Ivana Pibiri, Silvestre Buscemi, and Nicolò Vivona*
*Dipartimento di Chimica Organica “E. Paternò”, Università degli Studi di Palermo, Viale delle Scienze-Parco d’Orleans II, 90128 Palermo, Italy
Abstract
Molecular rearrangements of O-N bond-containing azoles (1-oxa-2-azoles) represent a wide class of reactions by which various heterocycle-to-heterocycle transformations can be performed as alternative synthetic methodologies. The material presented in this review is an extensive survey of both thermal and photochemical methodologies that have been applied to fluorinated oxadiazoles, and shows how molecular rearrangements can be an alternative and in some cases the most convenient route for the synthesis of several fluorinated heterocycles.