Regular Issue

Vol. 31, No. 10, 1990

24 data found. 1 - 24 listed
Communication | Regular issue | Vol 31, No. 10, 1990, pp.1733-1735
Published online:
DOI: 10.3987/COM-90-5500
A Regioselective and Flexibel Synthesis of Acronycine

Ramesh Chander Anand* and Arun Kumar Sinha

*Department of Chemistry, Indian Institute of Technology, Hauz Khas, New Delhi-110016, India

Abstract

A regioselective synthesis of acronycine has been described through a methodology which can conveniently be modified for the preparation of its analogues.

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1737-1743
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DOI: 10.3987/COM-90-5504
Intramolecular [2+2] Photocycloaddition of N1-(ω-Alkenyl)pyrimidines: Formation of Diazatricyclodiones

Chong Il Ahn, Ha Young Choi, and Bo Sup Hahn*

*Department of Chemistry, Ajou University, 5 Wonchun, Suwon 442-749, Korea

Abstract

Irradiation of N1-(ω-alkenyl)pyrimidines in a CH3CN solution gave parallel cycloadducts, diazatricyclodiones, as the sole photoproduct.

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1745-1750
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DOI: 10.3987/COM-90-5515
The Study of Metal Ion Catalyzed Carbon-Hydrogen Insertion of α-Alkoxy-α’-diazoketones Derived from Mandelic and Lactic Acids

Yung-Son Hon,* Rong-Chi Chang, and Tay-Yuan Chau

*Institutue of Chemistry, Academia Sinica, 128, Yan-Chiu-Yuan Road, Sec II, Nankang, Taipei,11529, Taiwan, R.O.C.

Abstract

The cupric acetylacetonate is the best catalyst to induce the carbon-hydrogen inserted reaction for the α-alkoxy-α’-diazoketones derivatives (5 and 6). The side reactions such as aromatic carbon-hydrogen insertion and rearrangement could be prevented.

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1751-1761
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DOI: 10.3987/COM-90-5517
[4+2]Cycloadditions of Pyrano[3,4-b]indol-3-ones with 1,2-Bis-acceptor Substituted Ethenes: First Evidence for a Non-concerted Diels-Alder Step

Ulf Pindur* and Houshang Erfanian-Abdoust

*Department of Chemistry and Pharmacy, University of Mainz, Saarstrasse 21, D-6500 Mainz, Germany

Abstract

The Diels-Alder reactions of pyrano[3,4-b]indole-3-ones (1) with 1,2-bis-acceptor substituted ethenes yield stable 1,2-dihydrocarbazoles and fully aromatized carbazoles. The results of stereochemical determinations in the 1,2-dihydrocarbazoles and, in one case, the occurrence of a bimolecular, diene-catalyzed dienophile isomerization provide the first evidence that a non-concerted [4+2]cycloaddition is mainly in operation. The pyrido[3,4-b]indol-3-one (11) was attacked by dienophiles only at the lactam nitrogen atom and cycloaddition did not take place.

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1763-1767
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DOI: 10.3987/COM-90-5537
Synthesis of Oligo-N-methylpyrrolecarboxamide Derivatives and Their Photochemical DNA Cleaving Activities

Eiji Nishiwaki, Hirofumi Nakagawa, Michika Takasaki, Toyomi Matsumoto, Hiromu Sakurai, and Masayuki Shibuya*

*Faculty of Pharmaceutical Sciences, University of Tokushima, Sho-machi 1, Tokushima 770-8505, Japan

Abstract

Synthesis of various oligo-N-methylpyrrolecarboxamide derivatives and their DNA cleaving activities under UV-A irradiation were described.

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1769-1772
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DOI: 10.3987/COM-90-5539
Thermolysis of 8-Aza- and 8-Oxabenzo[c]tricyclo[5.1.0.02,6]octanes: Formation of 3-Benzazocines and 3-Benzoxocins

Jyoji Kurita, Toshiko Aruga, and Takashi Tsuchiya*

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

Abstract

Flash vacuum pyrolysis of 8-aza- (10) and 8-oxabenzo[c]tricyclo[5.1.0.02,6]octanes (11) resulted in ring-expansion to give the novel 3-benzazocines (14) and 3-benzoxocins (16), respectively. In the case of 11, several kinds of rearrangement products were also obtained.

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1773-1776
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DOI: 10.3987/COM-90-5544
Structure of Ternatin A2, One of Clitoria ternatea Flower Anthocyanins Having the Unsymmetrical Side Chains

Norihiko Terahara,* Norio Saito, Toshio Honda, Kenjiro Toki, and Yutaka Osajima

*Department of Food Science and Technology, College of Horticulture, Minami-Kyushu University, Takanabe, Miyazaki 884, Japan

Abstract

The structure of ternatin A2 was identified as 3-O-(6-O-malonyl-β-D-glucopyranosyl)-3’-O-(6-O-(E-4-O-(6-O-(E-4-O-β-D-glucopyranosyl-p-coumaryl)-β-D-glucopyraonsyl)-p-coumaryl)-β-D-glucopyranosyl)-5’-O-(6-O-(E-4-O-β-D-glucopyranosyl-p-coumaryl)-β-D-glucopyranosyl)delphinidin.

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1777-1780
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DOI: 10.3987/COM-90-5549
Novel Thymidine Analogues via Reaction of Unprotected 5’-Deoxy-5’-iodothymidine with Dianions

Partha S. Ray* and Albert A. Jaxa-Chamiec

*Department of Chemistry, Searle Research and Development, High Wycombe, Buckighamshire HP12 4HL, U.K.

Abstract

Reaction of 5’-deoxy-5’-iodothymidine with a variety of dianions gave novel thymidine analogues in moderate to good yields.

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1781-1784
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DOI: 10.3987/COM-90-5559
Aromatic Cyclizatons of β-Aminoethyl Radicals and α-Carbamolymethyl Radicals. ortho-Substitution vs. ipso-Substitution

Hiroyuki Ishibashi,* Nobuyuki Nakamura, Katsuhiro Ito, Shinji Kitayama, and Masazumi Ikeda

*Kyoto Pharmaceutical University, Misasagi, Yamashina, Kyoto 607-8414, Japan

Abstract

On being treated with Bu3SnH, the N-benzyl-N-(β-bromoethyl)sulfonamide (4) underwent a homolytic ortho-substitution reaction to give the tetrahydroisoquinoline (6). In contrast, the N-arylmethyl-α-chloroacetamides (10) afforded the ipso-substitution products (11). A similar treatment of the N-naphthylmethyl derivative (16) provided the spiro-γ-lactam (17).

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Communication | Regular issue | Vol 31, No. 10, 1990, pp.1785-1788
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DOI: 10.3987/COM-90-5564
Oxidation Potentials of 1,2,3,4-Dibenzo[2.2.3]cyclazines, Peripheral 18π Electron Systems

Jun Yamauchi,* Takane Uchida, and Kiyoshi Matsumoto*

*College of Liberal Arts and Science, Kyoto University, Yoshida, Sakyou-ku, Kyoto 606-8501, Japan

Abstract

Cyclic voltammetry of 1,2,3,4-dibenzo[2.2.3]cyclazine and its derivatives was carried out ot support the previous observation of the cation radicals in these compounds. The observed oxidation potentials are compatible with the HOMO level instability arising from the introduction of the dibenzo-group in [2.2.3]cyclazien, as was presumed by the ESR observation.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1789-1799
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DOI: 10.3987/COM-90-5322
On the 2,4-Relative Stereochemistry of N-Substituted Oxazolidines Derived from Phenylglycinol

Siméon Arséniyadis, Pei Qiang Huang, Nelly Moreller, Jean-Claude Beloeil, and Henri-Philippe Husson*

*Institut des Chimie des Substances Naturelles, C.N.R.S., 1 avenue de la Terrasse, Bat. 27, 91198 Gif-sur-Yvette Cedex, France

Abstract

1H and 13C nmr spectroscopy using n.O.e difference, NOESY and ROESY techniques and 3J CH coupling constants allowed confirmation of the (2R, 4R) absolute configuration of the (R)-(-)-phenylglycinol derived oxazolidines 2M to 5M and demonstrated that the trans 2,4-relative stereochemisry was erroneosly implied on the basis of misinterpreted nmr spectra (H-4, H-5 assignements).

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1801-1809
Published online:
DOI: 10.3987/COM-90-5468
Synthesis of New Disubstituted Azolium Ylides

M. Teresa Gandasegui and Julio Alvarez-Builla*

*Departamento de Química Orgánica, Universidad de Alcalá de Henares, 28871 Alcalá de Henares, Madrid, Spain

Abstract

A series of several azolium methylides have been obtained by reaction of 1-phenacylazolium salts with the corresponding dipolarophiles in a two-phase system. Only by the reaction of a benzimidazolium derivative with dimethyl acetylenedicarboxylate 1,3-dipolar cycloaddition was observed.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1811-1817
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DOI: 10.3987/COM-90-5477
Studies on Dimethylhyddrazones of Heteroaryl Aldehydes. The Reactivity of 2-Formylfuran, 2-Formylthiophene and 1-Methyl-2-formylpyrrole N,N-Dimethylhydrazones with Methyl Propiolate and Diethyl Azodicarboxylate

Belén Abarca,* Rafael Ballesteros, Eugenia González, Pedro Sancho, José Sepúlveda, and Concepción Soriano

*Departamento de Química Orgánica, Facultad de Farmacia, Universidad de Valencia, Avda. Blasco Ibañez 13, 46010 Valencia, Spain

Abstract

The title hydrazones react with methyl propiolate giving the new 2-heteroarylpyridines (4, 5 and 6). The reaction with diethyl azodicarboxylate gives 1 : 1 Michael adducts except with formylthiophene hydrazone that gives the compound (14) a novel type of 1 : 1 adduct.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1819-1822
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DOI: 10.3987/COM-90-5487
Trinervine, a New Indole Alkaloid from Strychnos trinervis

Rabindranath Mukherjee,* Margareth de F. F. Melo, Cid A. de M. Santos, Eric Guittet, and Bhupesh C. Das

*Laboratório de Tecnologia Farmacêutica, Universidade Federal da Paraiba, 58051-970 Joao Pessoa, PB, Brazil

Abstract

A new indole alkaloid, trinervine (1), together with three known bases, bisnordihydrotoxiferine, longicaudatine, and normacusine B, was isolated from the roots of Strychnos rinervis (Vell.) Mart. Their structures were established by spectroscopic methods.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1823-1831
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DOI: 10.3987/COM-90-5507
Preparation of 5,6,7,8-Tetrahydro-7-aryl-3-methylisoxazolo[4,5-b]azepin-5(4H)-ones

Antonella Baracchi, Stefano Chimichi, Francesco De Sio, Donato Donati, Cecilia Polo, and Piero Sarti-Fantoni

*Dipartment di Chimica Organica, CNR Centro Composti Eterociclici, Università di Firenze, Via Gino Capponi 9, Firenze, Italy

Abstract

3-Methyl-4-nitro-5-styrylisoxazoles (1a-e) reacted with diethyl malonate to give the corresponding Michael adducts (2a-e) which have been hydrolyzed to 4-(3-methyl-4-nitroisoxazol-5-yl)-3-phenyl(chlorophenyl)butanoic acids (3a-e). Subsequent reduction of the nitro group of these acids afforded the title compounds (4a-e) by intramolecular cyclization.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1833-1836
Published online:
DOI: 10.3987/COM-90-5516
Photo and Thermally Induced Reaction of 3- and 4-Fluoropyridines with the Indole 1-Anion

Kazue Ohkura, Koh-ichi Seki,* Masanao Terashima, and Yuichi Kanaoka

*Faculty of Pharmaceutical Sciences, Higashi-Nippon-Gakuen University, Ishikari-Tobetsu, Hokkaido 061-02, Japan

Abstract

Photoreaction of 3-fluoropyridine with the indole 1-anion gave 1-(3-pyridyl)indole exclusively, albeit in low yield. 4-Fluoropyridine and the anion reacted in the dark to afford 1-(4-pyridyl)indole in good yield, however uv light retarded its formation.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1837-1846
Published online:
DOI: 10.3987/COM-90-5518
A Practical Synthesis, Optical Resolution and Determination of Absolute Configuration of Enantiomerically Pure 1S,2R-(+)- and 1R,2S-(-)-cis-2-(1-Pyrrolidinyl)cyclohexylamines: Important Precursor for a New Class of Sigma-Receptor Ligands and Anticonvulsant Drugs

Brian R. de Costa* and Lilian Radesca

*Laboratory of Medicinal Chemistry, National Institute of Diabetes Digestive and Kidney Diseases, National Institute of Health, Betheda, MD 20892-0815, U.S.A.

Abstract

Enantiomerically pure (+)- and (-)-cis-2-(1-pyrrolidinyl)cyclohexylamines ((+)- and (-)-4) were prepared starting with (±)-trans-2-aminocyclohexanol ((±)-5). The key step in the generation of the cis stereochemistry of (+)- and (-)-4 employed catalytic hydrogenation of the enamine mixture generated from condensation of pyrrolidine with (±)-2-(benzamido)cyclohexanone ((±)-7). An efficient optical resolution of (±)-4 was achiebed through two recrystallization s of the mandelate salts. The absolute configuration of (+)- and (-)-4 was assigned as 1R,2S and 1R,2S, respectively, based on conversion of (-)-4 to and comparison with the N-methyl derivative (-)-13 of known 1R,2S absolute configuration.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1847-1853
Published online:
DOI: 10.3987/COM-90-5519
New Naphthopyrone Derivatives from Cassia pudibunda

Irene Messana,* Franco Ferrari, Maria Salete B. Cavalcanti, and Eszter Gàcs-Baitz

*Istituto di Chimica, Università Cattolica del Sacro Cuore, L. F. Vito 1, 00168 Roma, Italy

Abstract

Further examination of the methanolic extract of the roots of Cassia pudibunda led to isolation of four new angular γ-naphthopyrones identified as 10-demethylflavasperone (1), 10-demethylflavasperone-10-sulphate (2), 10-demethylflavasperone-10-O-β-D-apiofuranosyl-(1->6)-O-β-D-glucopyranoside (3), and cassiapyrone-10-sulphate (7-methyl-10-demethylflavasperone-10-suophate) (4). The antimicrobial activity of the compounds is also reported.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1855-1860
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DOI: 10.3987/COM-90-5529
Studies on Isonitriles and Related Compounds. Synthesis of 1H-Pyrrole and 1H-Imidazole Derivatives via 1,3-Dipolar Cycloaddition

Ricardo Bossio, Stefano Marcaccini,* Paola Paoli, Roberto Pepino, and Cecilia Polo

*CNR, Centro di Studio Sulla Chimica e la Struttura dei Composti Eterociclici e lolo Applicazioni, c/o Dipartimento di Chimica Organica "Ugo Schiff", Università di Firenze, Via Gino Capponi 9, I-50121 Firenze, Italy

Abstract

4-Nitrobenzyl isocyanide (1) reacted with arylsulfenyl chlorides (2) to give isothiocarbamoyl chlorides (3). Treatment of 3 with NEt3 afforded nitrile ylides (4) which reacted with stoichiometric amounts of dimethyl acetylenedicarboxylate to give 1H-pyrroles (5) and with an excess of the same reagnent to give dimethyl-2-substituted maleates (7). The reaction of 4 with ethyl cyanoformate afforded 1H-imidazoles (6).

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1861-1872
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DOI: 10.3987/COM-90-5534
Structure of 6- or 8-Isoprenoid Substituted Flavonone: Chemical Shift of the Hydrogen-bonded Hydroxyl Group

Toshio Fukai and Taro Nomura*

*Faculty of Pharmaceutical Sciences, Toho University, 2-2-1, Miyama, Funabashi, Chiba 274-8510, Japan

Abstract

The proton signal of the hydrogen-bonded hydroxyl group of the 6-isoprenoid substituted flavonone was shifted more downfield than that of 6-nonsubstituted flavaonone. By comparison of the chemical shifts of the hydrogen-bonded hydroxyl groups of 8-(3",3"-dimethylallyl)-5,7,3',4'-tetrahydroxyflavanone (3) and its 6-isomer (4) isolated from Wyethia helenioides, the proposed structures 3 and 4 were reversed each other. Comparison of the chemical shift of the hydroxyl group is a facile method to discriminate the 6-isoprenoid substituted flavanone and the 6-nonsubstituted one.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1873-1878
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DOI: 10.3987/COM-90-5535
Bis(2-thienyl)ethylene Gives [4+2] Cycloadducts by Racdical Ion Pairs

Teresa Varea, Belén abarca, Rafael Ballesteros, and Gregorio Asensio*

*Departamento de Química Orgánica, Facultad de Farmacia, Universidad de Valencia, Calle Dr. Moliner, 50, E-46100 Burjassot (Valencia), Spain

Abstract

1,1-Bis(2-thienyl)ethanol reacts at room temperature in the absence of light with electron-deficient alkenes such as TCNE or DDQ ot give quantitatively [4+2] cycloadducts derived from 1,1-bis(2-thienyl)ethylene. The process was monitored by esr and it is shown that it is the first example of a cycloaddition involving a heterocyclic ring that occurs through the formation of intermediate radical ion pairs. Fragmentation of the DDQ adduct constitutes a straightforward new route to the 4,5-dicyanobenzo[b]thiophene skeleton.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1879-1888
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DOI: 10.3987/COM-90-5538
Tatsirine, a Diterpenoid Alkaloid from Delphinium tatsienense Franch

Xiaolin Zhang, John K. Snyder, Balawant S. Joshi, Jan A. Glinski, and S. William Pelletier*

*School of Chemical Sciences, Institute for Natural Products Research, The University of Georgia, Chemistry Building, Athens, Georgia 30602-2556, U.S.A.

Abstract

Tatsirine, isolated from the roots of Delphinium atsienense, has been assigned structure (2). The structure was established on the basis of homonulcear 1H COSY, fixed-evolution HECTOR, two-dimensional nOe and selective INEPT studies on 5.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1889-1894
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DOI: 10.3987/COM-90-5546
Demethylation of Norditerpenoid Alkaloids

Xihui Liang, Haridutt K. Desai, Balawant S. Joshi, and S. William Pelletier

*School of Chemical Sciences, Institute for Natural Products Research, The University of Georgia, Chemistry Building, Athens, Georgia 30602-2556, U.S.A.

Abstract

The reaction of the aconitine-type alkaloids delphinine and delphisine, and the lycoctonine-type alkaloids delsoline, ajacine, and deltaline has been carried out with HBr-AcOH in glacial acetic acid. These reactions proceed by parial demethylation and acetylation of the hydroxyl groups formed during the demethylation.

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Paper | Regular issue | Vol 31, No. 10, 1990, pp.1895-1902
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DOI: 10.3987/COM-90-5553
Furan Derivatives as 4π-Components in [4π+2π] Cycloaddition Reactions with 3-Cyanocyclopropene

Katsuhiro Saito,* Kazuaki Ito, and Kensuke Takahashi

*Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466, Japan

Abstract

[4π+2π]-Type cycloaddition reactions of 2-methoxycarbonyl-, 2-acetyl-, and 2-methylfurans with 3-cyanocyclopropene generated in situ from tricyclo[3.2.2.02,4]nonadiene derivative afforded 8-oxatricyclo[3.2.1.02,4]oct-6-ene derivatives, which further reacted with the furan to give [4π+2π]-type cycloadduct.

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24 data found. 1 - 24 listed