Special Issue

Ivar Ugi's Special Issues, Vol. 73, No. 1, 2007

72 data found. 31 - 60 listedFirst Previous Next Last
Paper | Special issue | Vol 73, No. 1, 2007, pp. 349 - 375
Published online: 29th June, 2007
DOI: 10.3987/COM-07-S(U)9
The Preparation and Characterization of Nineteen New Phthalidyl Spirohydantoins

István Lengyel,* Hardik J. Patel, and Ralph A. Stephani

*Department of Chemistry and bDepartment of Pharmaceutical Sciences, St. John’s University, 8000 Utopia Parkway, Jamaica, New York 11439, USA


Nineteen new N,N’-disubstituted phthalidyl spirohydantoins (6a-s) were prepared for the purpose of pharmacological testing. Their structure was deduced from the IR, 1H-NMR, 13C-NMR, mass spectra and elemental analysis. The two possible structural isomers - only one of which is formed - can be distinguished unequivocally on the basis of selective diastereotopicity of the α-methylene hydrogens adjacent to N-3’ of the hydantoin ring.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 377 - 392
Published online: 26th June, 2007
DOI: 10.3987/COM-07-S(U)8
Skeletal Diversity by Ugi Four-Component Coupling Reaction and Post-Ugi Reactions

Masato Oikawa,* Shinya Naito, and Makoto Sasaki*

*Laboratory of Biostructural Chemistry, Graduate School of Life Sciences, Tohoku University, Tsutsumidori-amamiya, Aoba-ku, Sendai 981-8555, Japan


Here we report a strategy to alter the skeletal complexity of Ugi four-component coupling reaction products by using allylations followed by ring-closing metathesis. Principal component analysis is also performed for these compounds.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 393 - 401
Published online: 20th July, 2007
DOI: 10.3987/COM-07-S(U)10
Facile One-Pot Synthesis of Tricyclic/Polycyclic Lactones

Jing Xu, Chunhao Yang,* Maojiang Wu, and Yuyuan Xie*

*State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, SIBS, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Shanghai, 201203 P.R.China


The reaction of substituted or unsubstituted 2-hydroxybenzaldehydes with 5, 6-dihydropyran-2-one in the presence of DMAP in DMSO afforded tricyclic/polycyclic lactones in good yields.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 403 - 417
Published online: 10th July, 2007
DOI: 10.3987/COM-07-S(U)11
A Versatile Synthesis of α-Amino Acid Derivatives via the Ugi Four-Component Condensation with a Novel Convertible Isonitrile

Kentaro Rikimaru, Arata Yanagisawa, Toshiyuki Kan, and Tohru Fukuyama*

*School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka-shi, 422-8526, Japan


The Ugi four-component condensation (4CC) reaction with the carbonate-type isonitrile 9 proceeded smoothly, and subsequent base treatment of the Ugi products 10 provided the N-acyloxazolidinones 11 in high yield. The N-acyloxazolidinone derivatives can be reacted with several hetero-nucleophiles, namely, reaction of 11 with thiolates gave thiol ester derivatives 16 efficiently.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 419 - 432
Published online: 20th July, 2007
DOI: 10.3987/COM-07-S(U)12
Generation and Reactivity of a Silylated Thiocarbonyl S-Methylide

Grzegorz Mloston,* Katarzyna Urbaniak, Anthony Linden, and Heinz Heimgartner*

*Institute of Organic Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland


The reaction of (trimethylsilyl)diazomethane with methyl (diethoxyphosphonyl)dithioformate (2), after elimination of N2 at -35°C, yields the 4,5-bis(trimethylsilyl)-1,3-dithiolane-2-phosphonate (8). This product is the result of the dimerization of the intermediate silylated thiocarbonyl ylide (4b) to give the cyclic sulfonium ylide (7), followed by the elimination of a disubstituted carbene. Trapping of the intermediate (4b) with maleimide (9), maleic anhydride (10), thiobenzophenone (11), and the phosphonylated dithioformate (2) yields the corresponding [2+3] cycloadducts (12), (13), (14b), and (18), respectively. The crystal structures of 13 and 14b have been established by X-Ray crystallography.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 433 - 449
Published online: 14th August, 2007
DOI: 10.3987/COM-07-S(U)13
Spirocyclic and Fused Derivatives of Maleimide Based on Intra- and Intermolecular Reactions of Carbonyl Ylides from Diazocarbonyl Compounds

Vsevolod V. Nikolaev, Bärbel Schulze, Heinz Heimgartner, and Valerij A. Nikolaev*

*Saint-Petersburg State University, University prosp. 26, Saint-Petersburg, 198504, Russia


The reaction of maleimide with Rh(II)-ketocarbenoids, derived from acyclic diazocarbonyl compounds, proceeds chemoselectively at the oxygen atom of the imidic C=O group to give carbonyl ylides as reactive intermediates. The carbonyl ylide generated from maleimide and ethyl diazoacetate reacts intermolecularly with the double bond of another molecule of maleimide to yield tricyclic spiroadducts via [3+2]-cycloaddition. Intramolecular stabilization is characteristic for carbonyl ylides with two bulky electron-withdrawing groups at the carbanionic center and occurs in two different ways, depending on the structure of the substituents: carbonyl ylides from diazomalonate, which possess two alkoxycarbonyl groups at the carbanionic C-atom, experience a 1,3-dipolar electrocyclization with formation of an oxirane, while carbonyl ylides with at least one α-acyl group, derived from diazoacetoacetate or diazoacetylacetone, undergo an intramolecular 1,5-dipolar electrocyclization to produce 1,3-dioxole derivatives of maleimide.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 451 - 460
Published online: 27th July, 2007
DOI: 10.3987/COM-07-S(U)16
Analysis of Benzylation Products of (+)-Catechin

Saki Nakamura, Kin-ichi Oyama, Tadao Kondo, and Kumi Yoshida*

*Graduate School of Inforamtion Science, Nagoya University, Chikusa, Nagoya 464-8601, Japan


Catechin, a flavanol compound from tea leaves, is one of useful starting materials in many synthetic studies toward various flavonoids. For synthesis, benzyl group is frequently chosen for protecting phenolic hydroxyl groups. To clarify the reactivity of each hydroxyl groups of catechin and realize an efficient reaction condition, we analyzed the products of the benzylation reaction of (+)-catechin. Two known and five new compounds were purified from the reaction mixture and their structure was determined. Not only O-benzylated products, but also 6 and/or 8-C-benzylated compounds were obtained. However, 3-OH group was never benzylated in this reaction.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 461 - 467
Published online: 20th July, 2007
DOI: 10.3987/COM-07-S(U)15
Onium Salt Supported Organic Synthesis in Water: Application to Ugi’s 4-Components Reaction

Aziz Ouach, Mathieu Pucheault, and Michel Vaultier*

*University of Rennes 1, UMR CNRS 6510, Campus of Beaulieu, General Leclerc Avenue#263, 35042 Rennes, France


The utilization of the Onium Salt Supported Organic Synthesis methodology for Ugi’s 4 components reaction in water is presented. An easy preparation of substrates followed by quantitative reactions led to peptidic moieties which are subsequently easily isolated in good yields and purities. Advantages of the OSSOS strategy including extreme simplification of purification and monitoring of the reaction are presented.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 469 - 480
Published online: 27th July, 2007
DOI: 10.3987/COM-07-S(U)19
Multicomponent Cyclocondensations of β-Ketosulfones with Aldehydes and Aminoazole Building Blocks

Eugene S. Gladkov,* Valentin A. Chebanov, Sergey M. Desenko, Oleg V. Shishkin, Svetlana V. Shishkina, Doris Dallinger, and C. Oliver Kappe*

*Christian Doppler Laboratory for Microwave Chemistry (CDLMC) and Institute of Chemistry, Karl-Franzens-University Graz, Heinrichstrasse 28, A-8010 Graz, Austria


The multicomponent reaction of methylsulfonylacetone (or α-methylsulfonylacetophenone) with aromatic aldehydes and aminoazoles (or urea) under microwave irradiation to yield 5,8-dihydroimidazolo[1,2-a]pyrimidines and 4,7-dihydro[1,2,4]triazolo[1,5-a]pyrimidines was studied. The influence of the type of aminoazole building block on the reactivity was established. In addition, an unusual reaction pathway for the Biginelli-type condensation of methylsulfonylacetone with aldehydes and urea leading to non-classical Hantzsch-type dihydropyridines was found.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 481 - 491
Published online: 7th August, 2007
DOI: 10.3987/COM-07-S(U)20
Microwave-Assisted Diels-Alder Reaction of 2H-Pyran-2-ones with Maleimides towards Fused Bicyclo[2.2.2]octenes

Kristof Kranjc and Marijan Kočevar*

*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, SI-1000 Ljubljana, Slovenia


An efficient, green access to functionalized and highly constrained heteropolycyclic derivatives via a microwave-assisted cycloaddition reaction is reported. The double Diels_Alder reaction of a series of 2H-pyran-2-ones with maleimide and its N-substituted derivatives takes place in an aqueous mixture (and in some cases as neat reaction) to give a variety of fused bicyclo[2.2.2]oct-7-enes.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 493 - 501
Published online: 25th July, 2007
DOI: 10.3987/COM-07-S(U)24
Efficient Synthesis of 6-Substituted Purine Derivatives Using Pd-Catalyzed Cross-Coupling Reactions with 2’-Deoxyguanosine O6-Tosylate

Fumi Nagatsugi,* Yuki Ogata, Shuhei Imoto, and Shigeki Sasaki

*Institute of Multidiciplinary Research for Advanced Materials Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai-shi, Miyagi Japan


6-Substituted purine analogs function in a variety of biological activities including antiviral pathways. A number of studies have been reported on the development of the efficient synthesis of these nucleoside analogs. We previously demonstrated that oligonucleotides containing 2-amino-6-vinylpurine derivatives react with the cytosine at the target site with extreme selectivity. This was the first finding that O6-tosylate derivative of guanosine worked as an efficient substrate for Pd(0)-catalyzed cross-coupling reaction with vinyltributylstannane to produce 2-amino-6-vinylpurine. In order to demonstrate usefulness of the tosylate precursor, in this study we investigated transition metal catalysts and ligands in achieving the cross-coupling reaction using boronic acids or Grignard reagents as a coupling partner.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 503 - 517
Published online: 10th August, 2007
DOI: 10.3987/COM-07-S(U)26
Ugi-Smiles Access to Quinoxaline Derivatives

Julie Oble, Laurent El Kaïm,* Marion Gizzi, and Laurence Grimaud*

*Laboratoire Chimie et Procédés, UMR 7652, Ecole Nationale Supérieure de Techniques Avancées, 32 Bd Victor, Paris 75015, France


Two different Ugi-Smiles post-condensations strategies have been used for new three and four-component formation of quinoxaline scaffolds. In the first approach, a one-pot hydrogenation-cyclization affords the heterocycle with loss of the initial isocyanide moiety. In the second one, the use of o-iodonitrophenol as starting phenol, coupled with copper catalyzed cyclization gave us similar quinoxaline derivatives resulting from a four coupling.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 519 - 536
Published online: 14th September, 2007
DOI: 10.3987/COM-07-S(U)28
Effect of Substituents at 1,4-Positions of Polycyclic Aromatic Compounds and Preparation of 2,3-Difunctionalized Pentacenes and Naphthacenes

Shi Li, Lishan Zhou, Zhiyi Song, Fengyu Bao, Ken-ichiro Kanno, and Tamotsu Takahashi*

*Catalysis Research Center, Hokkaido University and SORST, Japan Science and Technology Agency (JST), Kita-ku, Sapporo 001-0021, Japan


Effects of substituents at 1,4-positions of polycyclic aromatic compounds were investigated in the case of reduction of 2,3-bis(alkoxycarbonyl)arenes with the LiAlH4/AlCl3 system. 2,3-Bis(alkoxycarbonyl)dihydronaphthacenes and dihydropentacenes 1 were treated with a mixture of LiAlH4 and AlCl3. The products were dependent on the substituents at 1,4-positions. Similar type of influence of the substituents at 1,4-positions was observed in the oxidation of diols 2 to dialdehydes 4. Without substituents at 1,4-positions, dialdehydes 4 were conveniently obtained. However, with substituents at 1,4-positions, dialdehydes 4 were not obtained. Instead, 1,3-dihydroisobenzofuran-1,3-diol or 1,3-dihydroisobenzofuran-1-ol derivatives 5, 6 were obtained in good yields. Preparation of pentacene imides and pentacene carboxylic acid anhydride was also reported.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 537 - 554
Published online: 28th August, 2007
DOI: 10.3987/COM-07-S(U)31
Creation of New Promoters for Plant’s Root Growth: Its Application for the Syntheses of Vulcanine and Borreline, and for Combating Desertification at Gobi Desert in Inner Mongolia

Masanori Somei,* Shinsuke Sayama, Katsumi Naka, Kotaro Shinmoto, and Fumio Yamada

*Division of Pharmaceutical Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan


Various new 2-substituted indole-3-carbaldehydes are prepared. Structurally related alkaloids, vulcanine and borreline, are synthesized as well. Among the compounds, 2-haloindole-3-carbaldehydes are found to be potent promoters of plant’s root growth. Its successful preliminary application is reported for making Gobi desert in Inner Mongolia full of plant.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 555 - 566
Published online: 7th September, 2007
DOI: 10.3987/COM-07-S(U)32
Simple Approach to Some N-(5-Hydroxy-1-phenyl-1H-pyrazol-4-yl)benzamides

Karmen Cucek, Amalija Golobic, and Bojan Vercek*

*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, 1000 Ljubljana, Slovenia


A series of substituted 5-hydroxy-1H-pyrazoles (5) was prepared by treatment of 4-hydroxymethylidene-2-phenyloxazol-5(4H)-one (1) with ethanol followed by reaction with phenylhydrazines and subsequent treatment with NaOH. Structures of the pyrazoles (5p) and (5r) were confirmed by X-ray structure analysis.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 567 - 579
Published online: 17th August, 2007
DOI: 10.3987/COM-07-S(U)33
Novel Synthesis of Dihydrothiophene-2,5-diimine Derivatives by the Three-Component Reaction of Isocyanides with Enamines and Arylisothiocyanates

Maxim A. Mironov,* Maria N. Ivantsova, Maria I. Tokareva, and Vladimir S. Mokrushin

*Department of Technology of Organic Synthesis, Urals State Technical University, 620002 Ekaterinburg, Russia


A distribution of the products in the reaction of aryl isothiocyanates with isocyanides and 2,2-dialkylenamines has been studied in details. In range 55-60 °C this reaction results in the formation of dihydrothiophene-2,5-diimine derivatives, constitutions of which are proved by an X-ray analysis. In contrast at high temperature (above 110 °C) the major products in the present reaction are 2-imino-5-thiopyrrolidones. A one step pathway to dihydrothiophene structure has been elaborated.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 581 - 591
Published online: 7th August, 2007
DOI: 10.3987/COM-07-S(U)34
Improved Syntheses of D-Ribo- and 2-Deoxy-D-ribofuranose Phospho Sugars from Methyl β-D-Ribopyranoside

Tadashi Hanaya,* Yuko Koga, Heizan Kawamoto, and Hiroshi Yamamoto

*Department of Chemistry, Faculty of Science, Okayama University, Tsushima- naka, Okayama 700-8530, Japan


Methyl 4-deoxy-4-dimethoxyphosphinoyl-2,3-O-isopropylidene-β-D- ribopyranoside (12a) and methyl 2,4-dideoxy-4-dimethoxyphosphinoyl-β-D- erythro-pentopyranoside (20) were efficiently prepared respectively from methyl 2,3-O-isopropylidene-β-D-ribopyranoside (7a) and its 3,4-O-isopropylidene isomer (7b) in appreciably improved total yields compared with those via previously reported routes. Compounds (12a, 20) were led to D-ribofuranose and 2-deoxy-D-ribofuranose phospho sugars (4, 5).

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 593 - 602
Published online: 20th August, 2007
DOI: 10.3987/COM-07-S(U)38
Synthesis of 7-Substituted Derivatives of 5,8-Dimethylisoquinoline

Yukinori Nagao,* Katsuaki Hirota, Mizuho Tokumaru, and Kozo Kozawa

*Department of Industrial Chemistry, Faculty of Science and Technology, Science University of Tokyo, 2641 Yamazaki, Noda, Chiba 278-8510, Japan


7-Bromo-5,8-dimethylisoquinoline was selectively synthesized by the bromination of 5,8-dimethylisoquinoline obtained in five steps from p-xylene as a starting material. Further, 7-bromo-5,8-dimethylisoquinoline gave 7-amino-5,8-dimethylisoquinoline by the reaction with ammonia and various 7-anilino-5,8-dimethylisoquinolines via a palladium-catalyzed coupling reaction with anilines.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 603 - 615
Published online: 4th September, 2007
DOI: 10.3987/COM-07-S(U)39
Synthesis of Oxovanadium(IV) and Zinc(II) Complexes of 3-Hydroxy-4-(p-substituted)phenylthiazole-2(3H)-thiones with a S2O2 Coordination Mode and Their Insulin-Mimetic Activities

Mika Yamaguchi, Ryota Saito, Yusuke Adachi, Yutaka Yoshikawa, Hiromu Sakurai, and Akira Katoh*

*Department of Materials and Life Science, Faculty of Science and Technology, Seikei University, 3-3-1 Kitamachi, Kichijoji, Musashino-shi, Tokyo 180-8633, Japan


Oxovanadium(IV) and zinc(II) complexes with five kinds of 3-hydroxy-4-(p-substituted)phenylthiazole-2(3H)-thiones as bidentate ligands were newly synthesized. Zinc(II) complexes showed approximately 15 times higher in vitro insulin-mimetic activities than that of ZnSO4 as a positive control. Oxovanadium(IV) complexes also exhibited in vitro insulin-mimetic activities, in which a correlation between the activity and the Hammett’s constant of the substituent R was found. Among zinc(II) complexes, bis[2,3-dihydro- 2-thioxo-4-(p-nitrophenyl)-(6a) and bis[2,3-dihydro-2-thioxo-4-(p-chlorophenyl)- 3-thiazololato]zinc(II) (6b) substantially lowered the blood glucose levels in KK-Ay mice. Oral glucose tolerance tests for 6a and 6b indicated the improvement of the diabetic states of animals.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 617 - 625
Published online: 24th August, 2007
DOI: 10.3987/COM-07-S(U)40
Synthesis of Novel Urea Bridged Macrocyclic Molecules Using BTC

Mattan Hurevich, Yaniv Barda, and Chaim Gilon*

*Department of Organic Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel


Cyclic ureas have interesting pharmacological properties that have led to their use as analogs of bioactive compounds. Several synthetic routes for urea formation by cyclization of diamines are known, based on the nucleophilic reaction of the amines with phosgene or phosgene derivatives. We have developed a procedure for a triphosgene mediated, on-resin urea cyclization. Four novel urea macrocyclic molecules were synthesized in order to demonstrate the feasibility of this method.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 627 - 640
Published online: 17th August, 2007
DOI: 10.3987/COM-07-S(U)41
Synthetic Studies of Liposidomycin Degradation Product: Model Studies of Uracil Group Introduction

Shouhei Fukunishi, Makoto Ubukata, and Noriyuki Nakajima*

*Biotechnology Research Center, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan


The model studies of uracil group introduction for liposidomycin degradation product was described. A stereocontrolled synthesis of the liposidomycin diazepanone ring system having a phenyl substituent has been achieved. In the presence of an amino group on the diazepanone ring, the introduction of a uracil group did failed. In the model study with the Ns and formyl protecting group, the N-glycosylation proceeded smoothly to obtain the uracil compound in good yield.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 641 - 650
Published online: 17th August, 2007
DOI: 10.3987/COM-07-S(U)42
Asymmetric Alkylation of 2-Monosubstituted Indolin-3-ones

Kazuhiro Higuchi, Kouhei Masuda, Tamami Koseki, Masahiro Hatori, Masanori Sakamoto, and Tomomi Kawasaki*

*Meiji Pharmaceutical University, 2-522-1 Noshio Kiyose, Tokyo 204-8588, Japan


The asymmetric alkylation of 2-monosubstituted indolin-3-ones with optically active phase transfer catalysts (PTCs) has been studied. The prenylation of 2-benzyl indolin-3-one gave 2,2-dialkylated indolin-3-one 9a in 99% yield and 65% enantioselectivity. The alkylation was investigated with various 2-monosubstituted indolin-3-ones 5a-e and alkyl halides. The absolute configuration of 5d was determined by derivatization to the known amino acid.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 651 - 659
Published online: 28th August, 2007
DOI: 10.3987/COM-07-S(U)44
A Palladium(II) Complex Containing Imidazole Moieties. Synthesis and Structural Examination

Alexandrina D. Tanase, Eberhardt Herdtweck, Wolfgang A. Herrmann,* and Fritz E. Kühn*

*Department of Chemistry, Molecular Catalysis, Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany


trans-[PdCl2(NCyIm)2] was prepared through a route involving the corresponding silver precursor. 3-cyclohexyl-1-picolylimidazolium salt and Ag2O give a trans-[Ag(NCyIm)2]+ species with the imidazole ring bound at the N1 atom, not at the C2 atom.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 661 - 671
Published online: 20th August, 2007
DOI: 10.3987/COM-07-S(U)45
Facile Synthesis of Pyridazine-Based α-Helix Mimetics

Lionel Moisan, Trevor J. Dale, Naran Gombosuren, Shannon M. Biros, Enrique Mann, Jun-Li Hou, Fernando P. Crisostomo, and Julius Rebek, Jr.*

*Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, U.S.A.


The synthesis of an amphiphilic, nonpeptidic scaffold that mimics the presentation of i, i+4, and i+7 residues of an α-helix is presented. The approach uses a pyridazine core, and minimizes the number of C-C bond forming reactions. The synthesis of this Urea-Pyridazine-Piperazine (UPP) scaffold is versatile and its synthesis makes it suitable for the preparation of small libraries of low-molecular-weight α-helix mimetics that can be targeted to specific protein/protein interactions.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 673 - 688
Published online: 17th August, 2007
DOI: 10.3987/COM-07-S(U)46
Derivatization of Tetrafluorobenzo[c]thiophene. Preparation of Tetrafluorothiabenzoporphyrin

Hiroki Uoyama, Keisuke Nakamura, Marie Tukiji, Mina Furukawa, and Hidemitsu Uno*

*Division of Synthesis and Analysis, Department of Molecular Science, Integrated Center for Sciences, Ehime University, Matsuyama 790-8577 Japan


The Diels-Alder reactions of tetrafluorobenzo[c]thiophene with electron-deficient olefins such p-benzoquinone and bis(phenylsulfonyl)ethylene gave adducts in moderate yields, while no product was obtained in the reaction with butyl vinyl ether. The Vilsmeier reaction gave tetrafluorobenzo[c]thiophene-1-carbaldehyde in good yield. The aldehyde was converted to tetrafluorothiabenzoporphyrin.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 689 - 698
Published online: 7th September, 2007
DOI: 10.3987/COM-07-S(U)48
A Facile Sodium Alkoxide Mediated Ring Opening of Unactivated α-Dienyl-β-lactams: Synthesis of Unnatural Multicomponent β-Aminodienoic Esters

Amit Anand, Gaurav Bhargava, Maninder Singh Hundal, and Mohinder P. Mahajan*

*Department of Applied Chemistry, Guru Nanak Dev University, Amritsar - 143005, Punjab, India


A convenient synthesis of variedly substituted, multi component unnatural β-aminodienoic esters by sodium alkoxide amidiolysis of unactivated α-dienyl-β-lactams is reported.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 699 - 728
Published online: 9th October, 2007
DOI: 10.3987/COM-07-S(U)51
Multicomponent Synthesis of Novel 2- and 3-Substituted Dihydrobenzo[1,4]oxazepinones and Tetrahydrobenzo[1,4]diazepin-5-ones and Their Conformational Analysis

Luca Banfi,* Andrea Basso, Giuseppe Guanti, Paulina Lecinska, Renata Riva, and Valeria Rocca

*Department of Chemistry and Industrial Chemistry, University of Genova, via Dodecaneso 31, I-16146 Genova, Italy


By coupling an Ugi multicomponent condensation with a Mitsunobu reaction, a series of 2- and 3-substituted dihydrobenzo[1,4]oxazepinones and tetrahydrobenzo[1,4]diazepin-5-ones was synthesized in a very convergent manner. The strategy involves the use of substituted ethanolamines as amino components and of salicylic or N-methanesulphonyl anthranilic acid as carboxylic component. The general scope has been evaluated; in some cases better results have been obtained by reverting the order of the two reactions. A thorough conformational analysis on these products has been carried out through NMR, showing that in most cases a single conformation was strongly favoured.

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 729 - 742
Published online: 14th September, 2007
DOI: 10.3987/COM-07-S(U)54
Lithium Bromide-Promoted Three-Component Synthesis of Oxa-Bridged Tetracyclic Tetrahydroisoquinolines

Aude Fayol, Eduardo González-Zamora, Michèle Bois-Choussy, and Jieping Zhu*

*Institut de Chimie des Substances Naturelles, CNRS, 91198 Gif-sur-Yvette, France


Heating a toluene solution of an α-isocyanoacetamide (1), an aldehyde (2) and an aniline (3) in the presence of lithium bromide at 60 °C provides the oxa-bridged tetracyclic tetrahydroquinoline (4) in good to excellent yield as a mixture of two separable diastereoisomers. In this one-pot multicomponent reaction, one C-N, one C-O and three C-C bonds are formed with concomitant creation of five asymmetric centers and three heterocycles. Fragmentation of epoxy-tetrahydroquinoline (4) under mild acidic conditions affords 4,6-phenanthroline (5).

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 743 - 750
Published online: 9th October, 2007
DOI: 10.3987/COM-07-S(U)55
Synthesis of Thioaplysinopsin Analogs derived from 5-Dimethylaminomethylidene-2-thioxo-1,3-thiazol-4-ones

Renata Jakse, Uros Groselj, Gorazd Sorsak, Jurij Svete,* and Branko Stanovnik*

*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, P.O. Box 537, 1000 Ljubljana, Slovenia


Some new thioaplysinopsin analogs 4a-d were prepared from indole (3a) and or 2-methylindole (3b) and 5-dimethylaminomethylidene- (2a-c) or 5-ethoxymethylidene-2-thioxo-1,3-thiazol-4-ones (2d) derived rhodanine derivatives (1a,b). Cycloaddition of N-phenyl-4-chlorobenzonitrileimine to C=S bond in 4c and in thioaplysinopsin derivatives 6a,b afforded the corresponding spiro compounds 4,9-diphenyl-2-(4-chlorophenyl)-7-[1-(2-methylindol-3-yl)methylidene]-1,6-dithia-3,4,9-triazaspiro-[4.4]non-2-en-8-one (5) and 2-(4-chlorophenyl)-8-[(Z)-1-(2-methyl-1H-indol-3-yl)methylidene]-4,6-diaryl-1-thia-3,4,6,9-tetraazaspiro[4.4]non-3-en-7-one (7a,b).

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Paper | Special issue | Vol 73, No. 1, 2007, pp. 751 - 768
Published online: 14th September, 2007
DOI: 10.3987/COM-07-S(U)56
Rapid and Efficient Access to Meso-2,5-cis-disubstituted Pyrrolidines by Double Aza-Michael Reactions of Chiral Primary Amines

Leila Cabral dos Santos, Zineb Bahlaouan, Khadija El Kassimi, Claire Troufflard, Frédéric Hendra, Sandrine Delarue-Cochin, Mohamed Zahouily, Christian Cavé, and Delphine Joseph*

*Univ. Paris-Sud, Department of Organic Synthesis and Medicinal Chemistry, UMR CNRS 8076, 5, rue J.-B. Clément, F-92296 Châtenay-Malabry, France


The double aza-Michael reaction of enantiopure primary amines on bis α,β-unsaturated diesters has been studied under various activating conditions. High pressure allowed a rapid and efficient access to meso-2,5-disubstituted pyrrolidines.

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