Regular Issue

Vol. 53, No. 1, 2000

25 data found. 1 - 25 listed
Communication | Regular issue | Vol 53, No. 1, 2000, pp. 1 - 6
Published online:
DOI: 10.3987/COM-99-8596
X-Ray Structures of a Pair of Atropisomers of 1-(3’-Substituted Benzoyl)-2-naphthylindolines and Some Comments

Akiko Watanabe, Tetsuya Moriguchi, Fumikazu Ito, Yasuyuki Yoshitake, Masashi Eto, and Kazunobu Harano*

*Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-hon-machi, Kumamoto 862-0973, Japan


A pair of atropisomers due to restricted rotation about Csp3—Csp2 bond for 1-(3’-nitrobenzoyl)-2-(2”-hydroxynaphthyl)-3,3-dimethylindoline was isolated. The conformational analysis of both isomers was performed based on the crystallographic and 1 H-NMR spectral data.

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Communication | Regular issue | Vol 53, No. 1, 2000, pp. 7 - 10
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DOI: 10.3987/COM-99-8743
Preparation and a Novel Rearrangement Reaction of 1,2,3,4-Tetrahydro-9-hydroxy-β-carboline, and Their Applications for the Total Synthesis of (±)-Coerulescine

Masanori Somei,* Koichi Noguchi, Ryutaro Yamagami, Yumiko Kawada, Koji Yamada, and Fumio Yamada

*Faculty of Pharmaceutical Sciences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan


Novel 9-hydroxy-β-carboline derivatives were produced for the first time. A novel rearrangement reaction of 1,2,3,4-tetrahydro-9-hydroxy-β-carbolines was discovered to give 3,3-disubstituted oxindoles, which was successfully applied to the total synthesis of (±)-coerulescine.

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Communication | Regular issue | Vol 53, No. 1, 2000, pp. 11 - 14
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DOI: 10.3987/COM-99-8759
An Efficient Total Synthesis of Ellipticine

Minoru Ishikura,* Ayako Hino, and Nobuya Katagiri

*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan


A total synthesis of ellipticine could be attained through the palladium catalyzed tandem cyclization-cross-coupling reaction of indolylborate (2b) with vinyl bromide (3) as a key reaction.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 15 - 26
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DOI: 10.3987/COM-99-8703
Cathylation of 4,6-Dimethyl-2-oxopyridine-3-carbonitrile Derivatives Leading to the Synthesis of Furo[2,3-b;4,5-b’]dipyridines and Novel Tricyclic Furo[2,3,4-ij][2,7]naphthyridine

Chyun-Feng Lin, Yi-Feng Lin, Yan-Chung Lo, Kuo-Tung Chen, and Tsann-Long Su*

*Institute of Biomedical Sciences, Academia Sinica, Nankang, Taipei 11529, Taiwan, R.O.C.


Cathylation of ethyl 2-(3-cyano-4,6-dimethylpyridine-2-yloxy)acetate afforded a trace amount of new tricyclic furo[2,3,4-ij][2,7]naphthyridine derivative. An attempt was made for an alternate method for the synthesis this new tricyclic ring system. Treatment of 4,6-dimethyl-2-oxopyridine-3-carbonitrile (1) with various α-halocarbonyl compounds (such as chloropropanone or substituted 2-bromoacetophenones) gave a mixture of N- and O-alkylated compounds, which were readily converted into indolizines and 2-acetyl-3-amino- or 3-amino-2-benzoylfuro[2,3-b]pyridines. The 3-aminofuro[2,3-b]pyridine derivatives were further converted into furo[2,3-b;4,5-b’]dipyridines, but not the expected tricyclic furonaphthyridines, via N,O-acetylation and cyclization.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 27 - 35
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DOI: 10.3987/COM-99-8705
[N](3,5)Isoxazolophanes: Dynamic Behavior and Reaction with Electron-deficient Acetylene Leading to [N](2,6)Pyridinophanes

Hiroyuki Yamamoto and Makoto Nitta*

*Department of Chemistry, School of Science and Engineering, Materials Research Laboratory for Bioscience and Photonics, Waseda University, Shinjuku-ku, Tokyo 169-8555, Japan


1H NMR spectroscopy at various temperatures clarified the dynamic behavior of the oligomethylene chains for [8](3,5)isoxazolophane (1) and unsubstituted and 4-methyl-substituted [9](3,5)isoxazolophanes (2a,b). The energy barriers (ΔGc) for the bridge flipping are 18.6 kcalmol-1 (Tc 100 °C) for 1 and 11.5 kcalmol-1 (Tc-10 °C) for 2a. Compound (2b) does not undergo bridge flipping in temperatures ranging from 25 °C to 150 °C. The energy barriers for the pseudorotation are 11.1-11.2 kcalmol-1 (Tc -10 °C), 9.1 kcalmol-1 (Tc-70 °C), and 8.6 kcalmol-1 (Tc-80 °C) for 1, 2a, and 2b, respectively. The Mo(CO)6-induced reaction of 2a,b with dimethyl acetylenedicarboxylate afforded [9](2,6)pyridinophane derivatives, albeit in low yields.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 37 - 48
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DOI: 10.3987/COM-99-8708
Preparation of Lavendamycin Analogues

Christine Barbier, Arnaud Joissains, Alain Commerçon, Jean-François Riou, and François Huet*

*Laboratoire de Synthèse Organique, UPRESA CNRS 6011, Faculté des Sciences, Université du Maine, Avenue Olivier Messiaen, F-72085 Le Mans Cedex 9, France


A Pictet-Spengler type reaction conducted under modified conditions using a catalytic amount of pyridinium p - toluenesulfonate was used to prepare several lavendamycin (1) analogues.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 49 - 53
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DOI: 10.3987/COM-99-8713
An Alternative Route for the Preparation of 1-Benzostannepines, 1-Benzostibepines and 1-Benzosilepines via Te-Li Exchange of 1-Benzotellurepines

Haruki Sashida*

*Faculty of Pharmaceutical Science, Hokuriku University, School of Pharmacy, 3-Ho, Kanagawa machi, Kanazawa 920-1181, Japan


Treatment of 1-benzotellurepines (1) with t-BuLi in the presence of TMEDA in ether followed by addition of a metal reagent (Cl2SnBu2, Cl2SbPh and Cl2SiMe2) afforded the corresponding 1-benzostannepines (4), 1-benzostibepines (5) and 1-benzosilepines (6), respectively, in one pot via the tellurium - lithium exchange.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 55 - 68
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DOI: 10.3987/COM-99-8715
Photochemical Dimerization of Styrylnaphthofurans-II

Irena Skoric, Zeljko Marinic, and Marija Sindler-Kulyk*

*Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulicev trg 19, HR-10000 Zagreb, Croatia


Irradiation of styrylnaphthofurans (3a, 3b) [10-1 M] (benzene) under anaerobic conditions gives mainly dimeric products (65-70%): [2+2] ethene-ethene cycloaddition products (9a, 9b, 10a, 10b and 11a, 11b) (40-44%) and [2+2] ethene-furan cycloaddition products (12a, 12b) (20-22%). Minor quantities of electrocyclization products (7a, 7b) (3.5-4.5%) and dihydrocyclization products (8a, 8b) (3-4.5%) are also isolated. The structures of the products are based on 1H and 13C NMR spectra, applying COSY, LR COSY, APT, HETCOR and NOESY techniques.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 69 - 80
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DOI: 10.3987/COM-99-8720
1,3-Dipolar Cycloaddition Reactions of Benzonitrile Oxide to 2(1H )-Pyrazinone and Its N - and O - Methyl Derivatives

Antonino Corsaro,* Ugo Chiacchio, Venerando Pistarà, and Giancarlo Perrini

*Dipartimento di Scienze Chimiche, Università di Catania, Viale A. Doria 6, I-95125 Catania, Italy


2(1H)-Pyrazinone, which is in equilibrium with 2-pyrazinol, reacts with benzonitrile oxide (BNO) affording the N1-adduct with a 67% yield, while 2-methoxypyrazine gives two methoxypyrazinones (ca. 3%) and a biscycloadduct together with its degradation product, which derive from the two unisolable monocycloadducts to the C=N4 double bond. N-Methylpyrazinone gives only the degradation product (3.4%) of the initial monocycloadduct of BNO to C=N4 double bond.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 81 - 92
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DOI: 10.3987/COM-99-8723
Synthesis of Polycylic Systems via Diels-Alder Reactions of Sugar Derived Dienes

P. Areces Bravo,* M. C. Pozo Carrero, E. Román Galán, and J. A. Serrano Blázquez

*Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz, Spain


Several Diels-Alder reactions of sugar derived dienes (2Z, 4E)-1,3,6-triacetoxyhexa-2,4-diene (2) and (2Z, 4E)-1,3-diacetoxy-6-cyclohexylamino-hexa-2,4-diene (3) with a number of electron-deficient dienophiles were carried out in a completely stereoselective manner to give the corresponding cycloadducts or cascade reaction products. Subsequent chemical transformations yielded highly functionalized polycyclic systems having a controlled stereochemistry. The new compounds described in here keep the all-cis configuration at their centers.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 93 - 106
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DOI: 10.3987/COM-99-8727
Synthesis and Conformational Analysis of Some New Pyrano[2,3-c]xanthen-7-one and Pyrano[3,2-b]xanthen-6-one Derivatives with Cytotoxic Activity

Konstantinos Ghirtis, Nicole Pouli, Panagiotis Marakos,* Alexios-Leandros Skaltsounis, Stephane Leonce, Daniel H. Caignard, and Ghanem Atassi

*Department of Pharmacy, Division of Pharmaceutical Chemistry, University of Athens, Panepistimiopolis-Zografou, Athens GR-15771, Greece


The synthesis, conformational analysis and preliminary biological evaluation of some new pyrano[2,3-c]xanthen-7-ones and pyrano[3,2-b]xanthen-6-ones is described. Certain compounds possess interesting cytotoxic activity against murine leukemia L1210 cells.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 107 - 113
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DOI: 10.3987/COM-99-8729
A Convenient Synthesis of 4-Trifluoromethylimidazol-1-ols

Yasuhiro Kamitori*

*Department of Chemical Science and Engineering, Faculty of Engineering, Kobe University, Kobe 657-8501, Japan


1,1,1-Trifluoroalkane-2,3-dione 3-oximes easily obtainable from aldehyde dialkylhydrazones were reacted with aldehydes in the presence of ammonium acetate followed by treatment with 1N HCl affording 4-trifluoromethylimidazol-1-ols in good yields.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 115 - 126
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DOI: 10.3987/COM-99-8736
GABA-analogous Spirocyclic Amino Acid Esters, 5. N-Benzyl-7-azaspiro[4.5]decane-1-carboxylates

Markus Bendl, Michael Eder, Ingo Langhammer, and Ernst Urban*

*Institute of Pharmaceutical Chemistry, University of Vienna , Pharmaziezentrum, Althanstraße 14, A-1090 Vienna, Austria


N-Benzyl-7-azaspiro[4.5]decane-1-carboxylates (4a and 4b) were prepared in a seven step synthesis starting from ethyl cyclopentanonecarboxylate (5). Aminolysis of the β-keto ester (5) with benzylamine led to the β-keto amide (9) which gave the α-substituted β-keto amide (10) by addition of acrolein. Reduction of 10 with LiAlH4 resulted in a reductive cyclization yielding a mixture of the epimeric spirocyclic alcohols (12a and 12b, 3:1). Oxidation of the alcohols (12a and 12b) was archieved with (COCl)2/DMSO giving the spirocyclic ketone (14). Treatment of 14 with tosylmethyl isocyanide and tert-BuOK yielded a mixture of diastereomeric nitriles (15a and 15b, 6:4) which was separated by chromatography. Hydrolysis and esterification of 15a and 15b led to the diastereomerically pure amino acid esters (4a and 4b) which represent novel analogs of GABA with restricted conformational flexibility.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 127 - 134
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DOI: 10.3987/COM-99-8738
A Facile and Convenient Synthetic Method for Fluorine-containing 1H-Pyrrolo[3,2-h]quinolines

Etsuji Okada* and Norikado Tsukushi

*Department of Chemical Science and Engineering, Faculty of Engineering, Kobe University, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan


Aromatic nucleophilic nitrogen-nitrogen exchange reaction of N,N dimethyl-5,7-bis(trifluoroacetyl)-8-quinolylamine (1) with some amino acid derivatives gave the corresponding N-[5,7-bis(trifluoroacetyl)-8-quinolyl]amino acid derivatives (2) in excellent yields. Base-catalyzed cyclization of 2 afforded fluorine-containing 1H-pyrrolo[3,2-h]quinolines (3, 4) in high yields.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 135 - 142
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DOI: 10.3987/COM-99-8741
Preparation and Spectral Properties of the Nitrogen Analogs of (E)-5,5’-Diaryl- 3,3’-bifuranylidene-2,2’-diones and Their Derivatives

Hajime Irikawa* and Norihide Adachi

*Department of Chemistry, Faculty of Science, Shizuoka University, Ohya, Shizuoka 422-8529, Japan


(E)-5,5’-bis(2-methylphenyl)- and (E)-5,5’-bis(2,4,6-trimethyl-phenyl)-3,3’-bifuranylidene-2,2’-diones and their isomeric pyrano[4,3-c]pyran-1,5-diones were converted into the nitrogen analogs, in which the aryl groups were twisted relative to the parent skeletons, and had small conjugation effect. Another nitrogen analogs bearing coplanar aryl rings were prepared, and their UV-VIS and NMR spectral data were compared with those of the analogs having twisted aryl groups. Conjugation effect of the 2-alkylphenyl group is bathochromic shift by 24 nm. Steric compression due to coplanarity of the aryl rings causes a deshielding of a 1H NMR signal by Å` 0.6 ppm, and a shielding of a 13C NMR signal by Å` 5 ppm.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 143 - 149
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DOI: 10.3987/COM-99-8745
Total Synthesis of a Novel Cytotoxic Metabolite Gymnastatin A

Mukund K. Gurjar* and Pushpal Bhaket

*National Chemical Laboratory, Pune 411 008, India


The first total synthesis of a novel, potent cytotoxic metabolite gymnastatin A is described.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 151 - 158
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DOI: 10.3987/COM-99-8747
Anionic [3,3] Rearrangements of Cyclic Hydrazine Diacylates to Medium-Size Cyclic Diamides and Their Structures

Yasuyuki Endo,* Takuya Uchida, and Kentaro Yamaguchi

*Graduate School of Pharmaceutical Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan


The anionic rearrangement of N,N’-dimethyl-N,N’-diacylhydrazines to 1,2-disubstituted succinamides proceeds in the presence of a ajacent enolate- stabilizing substituent such as a phenyl group. However, a substituent that poorly stabilizes the α-carbanion results in an extremely low yield of the products. The [3,3] sigmatropic rearrangement generally requires a chair form for the cyclic six-centered transition state. When the dienolates of N,N’-diacylhydrazines have favorable steric factors for the cyclic transition state, the rearrangement seems to proceed smoothly. The diacylates of 5- to 8-membered cyclic hydrazine which readily adopt a favorable conformation for the [3,3] rearrangement readily rearrange to 9- to 12-membered cyclic diamides.

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Paper | Regular issue | Vol 53, No. 1, 2000, pp. 159 - 172
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DOI: 10.3987/COM-99-8750
Reactions of Tetrasulfur Tetranitride Antimony Pentachloride Complex (S4N4·SbCl5) with Primary β-Enaminones and β-Enamino Esters: Synthesis of 4-Substituted 3-Aroyl- and 3-Ethoxycarbonyl-1,2,5-thiadiazoles

Su-Hak Bae, Kyongtae Kim,* and Young Ja Park

*Department of Chemistry, Seoul National University, Seoul 151-742, Korea


The reaction of tetrasulfur tetranitride antimony pentachloride complex (S4N4·SbCl5) with 3-amino-3-alkyl-1-aryl-2-propenones and 3-amino-1,3-diaryl-2-propenones in toluene at 100°C produced 4-substitued 3-aroyl-1,2,5-thiadiazoles (3a-p) in 12 to 57% yields. Similarly treatment of β-enamino esters with S4N4.SbCl5 complex under the same conditions as for the reaction with β-enaminones gave ethyl 3-aryl-1,2,5-thiadizole-4-carboxylates (3q-x) in 41 to 54% yields. The formation of the products may be explained by the same mechanism as that proposed for the formation of 1,2,5-thiadizoles from 5-substitued 3-alkyl- and 3-aryl-isoxazoles and S4N4.SbCl5 complex.

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Note | Regular issue | Vol 53, No. 1, 2000, pp. 173 - 181
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DOI: 10.3987/COM-99-8689
Efficient Syntheses of (S)-4-Hydroxy-2-pyrrolidinone Derivatives

Osamu Kanno, Masao Miyauchi, and Isao Kawamoto*

*Medicinal Chemistry Research Laboratories, Sankyo Co., Ltd., 1-2-58 Hiromachi, Shinagawa-ku, Tokyo 140-8710, Japan


Efficient syntheses of (S)-4-hydroxy-2-pyrrolidinone ((S)-2) and (R)-4-acetylthio-2-pyrrolidinone (5), which are key intermediates of oral carbapenem CS-834, were studied. The most efficient route to (S)-2 from (S)-3-hydroxybutyrolactone (8) was accomplished in high yield via (S)-N-allyl-3-(1-ethoxy)ethoxy-4-hydroxybutyramide (14).

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Note | Regular issue | Vol 53, No. 1, 2000, pp. 183 - 190
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DOI: 10.3987/COM-99-8702
Sensitized Photoreduction of Nitrosoazoles on Titanium Dioxide

Andrea Pace, Silvestre Buscemi, Nicolò Vivona,* and Tullio Caronna

*Dipartimento di Chimica Organica “E. Paternò”, Università di Palermo , Viale delle Scienze-Parco D’Orleans II, 90128 Palermo, Italy


The photosensitized reduction of some 4-nitrosopyrazoles and 4-nitrosoimidazoles using titanium dioxide as a photocatalyst has been investigated. The photoreaction produces the corresponding 4-aminoazoles and assumes an initial electron transfer from the conduction band of the excited titanium dioxide to the nitroso compound, followed by hydrogen transfer from the solvent. The photoreduction reaction takes also place by irradiating nitrosoazoles in the presence of triethylamine in acetonitrile, pointing out the electron transfer also to occur from a ground state donor to the excited nitrosoazole.

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Note | Regular issue | Vol 53, No. 1, 2000, pp. 191 - 195
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DOI: 10.3987/COM-99-8722
5-Butyl-3,5-diaryl-4,5-dihydro-1,2,4-oxadiazoles, and a One-Step Synthesis of 4,4-Dibutyl-2-phenylbenzo-1,3-oxazine

Rajendra M. Srivastava,* Maurício F. Rosa, Carlos Eduardo M. Carvalho, Samira da G. M. Portugal, Ira M. Brinn, Maria da Conceição Pereira, and Octávio A. C. Antunes

*Departamento de Química Fundamental, Universidade Federal de Pernambuco, Cidade Universitária, 50.740-540 Recife, PE, Brazil


The synthesis of 5-butyl-3,5-diaryl-4,5-dihydro-1,2,4-oxadiazoles is described. The present work also describes the discovery of a reaction leading to the conversion of 5-butyl-5-(2-hydroxyphenyl)-3-phenyl-4,5-dihydro-1,2,4-oxadiazole (1d) to 4,4-dibutyl-2-phenylbenzo-1,3-oxazine (3).

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Note | Regular issue | Vol 53, No. 1, 2000, pp. 197 - 204
Published online:
DOI: 10.3987/COM-99-8730
Regioselective Aminomethylations of Bicyclic Phenols

Jos Lange,* Sonja Hoogeveen, Willem Veerman, and Henri Wals

*Solvay Pharmaceuticals Research Laboratpries, Medicinal Chemistry Department, P. O. Box 900, 1380 DA Weesp, The Netherlands


The regioselectivity in the aminomethylations (the Mannich reaction) of bicyclic phenols has been studied. Highly regioselective Mannich reactions enable easy synthetic access to novel bicyclic dialkylaminomethylphenols under very mild reaction conditions.

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Note | Regular issue | Vol 53, No. 1, 2000, pp. 205 - 211
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DOI: 10.3987/COM-99-8732
An Expeditious Synthesis of Pyrrolo[3,4-d]pyrimidine-2,4-dione from Uracil

Michael N. Zimmerman, Norman H. Nemeroff, Charles W. Bock, and Krishna L. Bhat*

*Department of Chemistry, School of Science and Health, Philadelphia University, Philadelphia, PA 19144, U.S.A.


An efficient, practical and cost effective synthesis of the title compound has been realized from uracil. The key step is the construction of the pyrrole ring using tosylmethylisocyanide (TosMIC) methodology. The structure of uracil, reaction intermediates and the final product were investigated using density functional calculations.

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Note | Regular issue | Vol 53, No. 1, 2000, pp. 213 - 218
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DOI: 10.3987/COM-99-8734
Synthesis of Mesomeric Betaines, [1,2,4]Triazolo[2,3-a]pyridiniumides, via Back-donated 1,6-Cyclization

Yoshiro Matsuda,* Keisuke Katou, Chieko Motokawa, and Takashi Uemura

*Faculty of Environmental Studies, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki 852-8521, Japan


The reaction of [1,2,4]triazolium salts (4a,b) with polarized alkenes (1a,b, 2a) in the presence of K2CO3 in CHCl3-EtOH gave the corresponding triazolium N-allylides (5a-c). Thermolyses of the N-allylides (5a-c) afforded the 7-imino[1,2,4]triazolo[2,3-a]pyridiniumide derivatives (6a,b) and the 7-oxo-[1,2,4]triazolo[2,3-a]pyridiniumide derivative (7a). Similar treatment of the salts (4a,b) with alkenes (1c, 2b) directly yielded mesomeric betaines (7b,c), while the reaction of the salt (4b) with alkene (2c) gave the pyrrolo[2,1-f][1,2,4]triazine derivative (8).

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Note | Regular issue | Vol 53, No. 1, 2000, pp. 219 - 224
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DOI: 10.3987/COM-99-8740
An Efficient Synthesis of (±)-cis-2-Amino-6-hydroxy-9-[4’-hydroxyethyl-2’-cyclopenten-1’-yl]purine

Won Kim, Hyangdug Kim, and Hakjune Rhee*

*Department of Chemistry, Hanyang University, Ansan, Kyunggi-do 425-791, Korea


The synthesis of a carbovir analogue, (±)-cis-2-amino-6-hydroxy-9-[4’-hydroxyethyl-2’-cyclopenten-1’-yl]purine (2) was achieved from 2,5-norbornadiene (3) in six steps and 31 % overall yield. This route involves a Meinwald rearrangement, one-pot operation (acid-hydrolysis and subsequent sodium borohydride reduction), and a Pd(0)-catalyzed coupling reaction.

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25 data found. 1 - 25 listed