Regular Issue

Vol. 32, No. 10, 1991

17 data found. 1 - 17 listed
Communication | Regular issue | Vol 32, No. 10, 1991, pp. 1869 - 1873
Published online:
DOI: 10.3987/COM-91-5780
Nucleophilic Addition to Homochiral N-Acylisoquinolinium Salts. Asymmetric Synthesis of (+)-Carnegine

Daniel L. Comins* and Mohamed M. Badawi

*Department of Chemistry, North Carolina State Univesity, Raleigh, NC 27695-8204, U.S.A.


The asymmetric addition of methyl nucleophiles to homochiral N-acylisoquinolinium salts was studied and utilized in a synthesis of the tetrahydroisoquinoline alklaoid, (+)-carnegine.

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Communication | Regular issue | Vol 32, No. 10, 1991, pp. 1875 - 1878
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DOI: 10.3987/COM-91-5839
Novel Synthesis of Optically Active Lactones from 4-Thianone

Haruo Matsuyama,* Sana Fujii, and Nobumasa Kamigata

*Department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan


Enantioselective synthesis (>92% e.e.) of quaternary carbon centers through Michael-type alkylation of chiral imines of 3-alkyl-4-thianones with methyl acrylate and successive diastereoselective synthesis of optically active lactones are described.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1879 - 1895
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DOI: 10.3987/COM-90-5637
Heterocycles from Nitrile Imines. Part IV. Chiral 4,5-Dihydro-1,2,4-triazin-6-ones

Mustafa M. El-Abadelah,* Ahmad Q. Hussein, and Bassam A. Thaher

*Chemistry Department, Faculty of Science, University of Jordan, Amman 11942, Jordan


The reaction of nitrile imines (II) with α-amino esters (III) proceeds with no detectable racemization and constitutes a convenient synthetic route to 4,5-dihydro-1,2,4-triazin-6-one (IV). Permanganate oxidation of the heterocyclces (IV) affords the corresponding 1,2,4-triazin-6-one (V). The reaction of (II) with β-amino esters gives the respective acyclic amidrazone adducts (VI).

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1897 - 1912
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DOI: 10.3987/COM-91-5672
Bridgehead Nitrogen Heterocycles. Part V. Synthesis of Some 1,3,4-Oxa/Thiadiazolo[3,2-a]pyrimidin-5-ones, 1,3,4-Oxa/Thiadiazolo[3,2-a][1,3,5]triazin-7-thiones, 1,3,4-Thiadiazolo[3,2-a][1,3,5]triazine-5(6H,7H)-thiones, 1,2,4-Triazolo[3,4-b][1,3,4]thiadiazine and Thiadiazoles Derivatives

Probin Chandra Gogoi, Mantu Moni Dutta, and Jiban Chandra Sarmah Kataky*

*Regional Research Laboratory, Jorhat 785 006, Assam, India


1,3,4-Oxa/thiadiazolo[3,2-a]pyrimidin-5-ones (7a-d, 8a-d), 1,3,4-oxa/thiadiazolo[3,2-a][1,3,5]triazin-7-thiones (11a-c, 12a-c), 1,3,4-oxa/thiadiazolo[3,2-a][1,3,5]triazin-5(6H,7H)-thiones (15a-l, 16a-l) , 1,2,4-triazolo[3,4-b][1,3,4]thiadiazines (18a-e) and 1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles (19a-o) were synthesized. The physical and spectral data of the new compounds were described.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1913 - 1921
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DOI: 10.3987/COM-91-5799
Reactions of 3,5-Dimethyl-4-nitroisoxazole with Cyclic Enamines and 1-Diethylaminopropyne

Rodolfo Nesi,* Donatella Giomi,* Sandro Papaleo, Stefania Turchi, Paolo Dapporto, and Paola Paoli

*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


3,5-Dimethyl-4-nitroisoxazole (1) was found to undergo tandem condensation-cyclization processes with 4-(1-cyclopenten-1-yl)- and 4-(1-cyclohexen-1-yl)morpholine in ethanol solution to give, through the intermediates (4) and (7), the N-oxides (5) and (9), respectively. The reactivity of 1 towards 1-diethylaminopropyne in different solvents was also investigated; the structure of the unexpected acyloxime (13), coming from the above reagents in acetonitrile, was determined by an X-ray analysis. Plausible mechanistic pathways for these new reactions are suggested.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1923 - 1931
Published online:
DOI: 10.3987/COM-91-5805
Synthesis and Application of Imidazole Derivatives. Synthesis of Pyrido[1,2-a]benzimidazolone Derivatives

Shunsaku Ohta,* Teruyuki Yuasa, Yoshihiro Narita, Ikuo Kawasaki, Eiji Minamii, and Masayuki Yamashita

*Kyoto Pharmaceutical University, Misasagi, Yamashina-ku, Kyoto 607-8412, Japan


Pyrido[1,2-a]benzimidazole derivatives (12a and 19a) were synthesized in moderate yields via an intramolecular aldol-condensation of 2-acetyl-1-formylmethylbenzimidazole (11) and an intramolecular acylation of the acylimidzolide (18) prepared from 2-ethoxycarbonylmethyl-1-(2-carboxyethyl)benzimidazole (17), respectively.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1933 - 1945
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DOI: 10.3987/COM-91-5808
Synthesis of 11-Aminosubstituted 6,8-Dimethyl-12H-[1]benzo[5,6]thiopyrano[2,3-c]quinolin-12-ones as Benzo Analogues of Lucanthone

Martine Croisy-Delcey,* Christiane Huel, Alain Croisy, and Emile Bisagni

*URA 1387 CNRS, Section de Biologie Bâtiments 110-112, Institut Curie, 15 Rue Georges Clémenceau 91405 Orsay, France


Condensation of acetonyl 2-methyl-5-chlorophenyl sulfide with potassium isatates led to 2-methyl-3-(2-methyl-5-chlorophenylthio)-4-quinolinecarboxylic acids. Polyphosphoric acid cyclodehydration then afforded 6,8-dimethyl-11-chloro-12H-[1]benzo[5,6]thiopyrano[2,3-c]quinolin-12-ones whose substitution by dialkylaminoalkylamines gave the title compounds. Whereas 2- and 3-methoxy-substituted products were transformed into their phenolic derivatives by hydrobromic acid. Regioselective oxidation of the 6-methyl group successively led to 6-formyl, 6-carboxy and 6-H- series. Evaluation of cytotoxic and antitumor properties showed that these new benzolucanthone analogues are devoid of biological activity.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1947 - 1953
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DOI: 10.3987/COM-91-5819
Easy and Efficient SNAr Reactions on Halopyridines in Solvent Free Conditions

André Loupy,* Noelle Philippon, Philippe Pigeon, and Hervé Galons

*Laboratoire des Rèactions Sélective sur Supports, UA CNRS-478, Bâtiment 410, Universite Paris-Sud 91405 Orsay Cedex, France


Solid-liquid phase transfer catalysis (PTC) without added solvent efficiently promotes SNAr reactions on halopyridines with a variety of anionic nucleophiles generated in situ. This methodology gives access to substituted pyridines in very simplified conditions depending on halide nature. Mechanistic investigations are proposed.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1955 - 1960
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DOI: 10.3987/COM-91-5824
C-Nucleosides. 16. A Synthesis of 1,5-Benzodiazepin-2-one Homo-C-nucleoside through Condensation of 1,2-Diaminobenzene with 5-Hydroxy-5-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)furan-2(5H)-one

Yasutaka Ito, Chihiro Ito, and Isamu Maeba*

*Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku, Nagoya 468-8503, Japan


The novel ring transformation of 5-hydroxy-5-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)furan-2(5H)-one (1) with 1,2-diaminobenzene to 1,5-benzodiazepin-2-one is described. Treatment of 1 with 1,2-diaminobenzene followed by dehydrgenation with 2,3-dichloro-5,5-dicyano-p-benzoquinone (DDQ) and p-toluenesulfonic acid afforded 4-[1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-oxo]-1,3-dihydro-2H,-1,5-benzodiazepin-2-one (2) as the major product. A possible mechanism for this reaction is proposed. The removal of the sugar protecting groups in 2 afforded the deprotected homo-C-nucleoside (5).

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1961 - 1967
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DOI: 10.3987/COM-91-5825
DNA-based Isolation and the Structure Elucidation of the Budmunchiamines, Novel Macrocyclic Alkaloids from Albizia amara

John M. Pezzuto,* Woongchon Mar, Long-Ze Lin, Geoffrey A. Cordell, Andras Neszmélyi, and Hildebert Wagner

*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.


On the basis of DNA affinity, a novel isolate was obtained from an extract prepared from the seeds of Albizia amara. As determined by a series of spectroscopic techniques, the isolate was structurally defined as a mixture of three macrocyclic alkaloids of the pithecolobine type that differed only in the length of the aliphatic side chain. The 1H - and 13C-nmr spectral parameters were unambiguously assigned to these alkaloids, which were given the trivial names budmunchiamine A, B or C. With the exception of former studies performed with Pithecolobium saman, this is the only other report of pithecolobine alkaloids being found in nature.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1969 - 1972
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DOI: 10.3987/COM-91-5828
Chiral Prodyes: Synthesis and Full Characterization of (S)-1-Phenylethylamides of the Optically Active O-Methyldihydrofluoresceins

Malgorzata Brzostowska, Arnold Brossi,* and Judith L. Flippon. Anderson

*Laboratory for the Structural Biology, NIDDK, National Instutute of Health, Bethesda, MD 20892-0815, U.S.A.


O-Dihydrofluorescein (3) on reaction with (S)-(—)-1-phenylethylamine afforded aminde (5) as a mixture of diastereomers which resisted chromatographic separation. The mixture of amides (6) and (7), however, obtained from 5 by catalytic hydrogenation could be separated by hplc. The X-ray analysis of amide (6) showed that it has the (9S)-absolute configuration. This result attests that it is possible to obtain dihydrofluoresceins with differently substituted benzene rings in the form of enantiomers.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1973 - 1981
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DOI: 10.3987/COM-91-5829
Rearrangement of N-Ureidopyrroles: A Case of Mononuclear Heterocyclic Rearrangement Involving an Aromatic Heterocycle as Carbon-Nitrogen-Nitrogen Sequence

Gabriella Macaluso, Giuseppe Cusmano,* Girolamo Cirrincione, Anna Maria Almerico, and Patrizia Diana

*Dipartimento di Chimica Organica, Università digli Studi di Palermo, Via Archirafi 20 90123 Palermo, Italy


The rearrangement, under basic conditions, of the N-ureidopyrroles (8) directly led to the pyrrolylalkenes (14). The reaction was explained in terms of initial mononuclear heterocyclic rearrangement leading to the pyrrolo[1,2-c][1,2,3]triazoles (12) followed by their decomposition to the final products under the reaction conditions. Attempts to thermally rearrange compound (8b) only gave products of decomposition of the ureido moiety.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1983 - 1988
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DOI: 10.3987/COM-91-5830
Norditerpenoid Alkaloids from Delphinium menziesii DC

Fang Sun, Michael Benn,* and Walter Majak

*Department of Chemistry, University of Calgary, Calgary, Alberta, T2N 1N4, Canada


An investigation of the alkaloids of Delphinium menziesii resulted in the isolation and identification of eleven norditerpenoid alkaloids, of which ten were known and one was new: the latter, named delmenzine, corresponded to 1-O-desmethyldelelatine.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 1989 - 2004
Published online:
DOI: 10.3987/COM-91-5848
Diels-Alder Reaction of Photoenol of 2-Methylbenzaldehyde with 5-Alkyldene-1,3-dioxane-4,6-dione Derivatives

Takashi Tsuno and Kunio Sugiyama*

*Department of Industrial Chemistry, College of Industrial Technology, Nihon University, 1-2-1, Izumi-cho, Narashino, Chiba 275-8575, Japan


Spiro- and polyspirocyclic compounds containing the 1,2,3,4-tetrahydro-1-naphthol structure were obtained by the Diels-Alder reaction of the photoenol of 2-methylbenzaldehyde with 5-alkylidene-1,3-dioxane-4,6-dione derivatives. The cycloaddition proceeded regio- and stereoselectively. However, in the case using 5-benzylidene-2,2-dimethyl-1,3-dioxane-4,6-dione and diethyl isobutylidenemalonate, the cycloaddition failed.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 2005 - 2014
Published online:
DOI: 10.3987/COM-91-5852
DDQ Oxidation of Ring-A Methoxylated 11b-Methoxycarbonyl-2,3,5,6,11,11b-hexahydro-3-oxo-1H-indolizino[8,7-b]indoles

Krishnaswamy Narayanan and James M. Cook*

*Department of Chemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, U.S.A.


A study of the oxidation of ring-A methoxylated 11b-methoxycarbonyl-2,3,5,6,11,11b-hexahydro-3-oxo-1H-indolizino[8,7-b]indoles (8a - 8e) with DDQ in aqueous tetrahydrofuran was carried out. Treatment of 8a - 8c under these conditions effected regiospecific oxidation at C-6 in yields ranging from 40-73% to provide the corresponding ring-A methoxylated 3,6-dioxo-1H-indolizino[8,7-b]indoles (12a -12c), respectively. The oxidation of the 7,8,9-trimethoxy analog (8d) also gave the 6-oxo derivative (12d), albeit in low yield. In contrast, the reaction of 8,10-dimethoxyindolizino[8,7-b]indole (8e) with DDQ (aq. THF) generated the quinone (12e), the structure of which is reminescent of the mitomycins. A proposed pathway for the origin of quinone (12e) is presented.

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Paper | Regular issue | Vol 32, No. 10, 1991, pp. 2015 - 2022
Published online:
DOI: 10.3987/COM-91-5853
Radical Nucleophilic Carbamoylation of 1,2,3-Triazine Derivatives

Kazuhiro Nagata, Takashi Itoh, Mamiko Okada, Hiroyuki Takahashi, and Akio Ohsawa*

*School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan


Radical nucleophilic carbamoylation was carried out to various 1,2,3-triazine derivatives. In the case of parent triazines as substrates, Minisci’s system was not effective, and in the absence of acid, a small amount of radical adduct was obtained. Triazinium dicyanomethylides reracted with carbamoyl radical to give 5-carbamoyltriazines in good yields. Other 1,2,3-triazine derivatives were also investigated.

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Review | Regular issue | Vol 32, No. 10, 1991, pp. 2023 - 2041
Published online:
DOI: 10.3987/REV-91-435
The Relationship between Bond Type, Bond Order and Bond Lengths. A Re-evalution of the Aromaticity of Some Heterocyclic Molecules

Vernon G. S. Box

*Department of Chemistry, City College of the City University of New York, Convent Avenue @ 138th Street, New York, NY 10031, USA.


Traditionally, we have described the type of a bond in terms of its location along a continuum from single to triple bond. A review of the bond lengths of a variety of molecules (from the X-ray crystallographic data), along with VESCF calculations on some isoelectronic analogues of enamines, and their nmr spectroscopic data, indicated that bonds can only occur in integral units and that no bond can be of an intermediate type. This conclusion leads to a redifinition of aromaticity which definitively reveals the possible aromaticity of heterocyclic molecules.

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17 data found. 1 - 17 listed