Regular Issue

Vol. 36, No. 11, 1993

21 data found. 1 - 21 listed
Communication | Regular issue | Vol 36, No. 11, 1993, pp. 2437 - 2440
Published online:
DOI: 10.3987/COM-93-6499
A Facile Synthesis of 4-Arylbutyrolactones via the Palladium-catalyzed Arylation of 1,3-Dioxep-5-ene

Takao Sakamoto,* Yoshinori Kondo, and Hiroshi Yamanaka

*Pharmaceutical Institute, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan


1,3-Dioxep-5-ene was arylated by using Heck reaction, and the arylated 1,3-dioxep-4-ene derivatives were easily converted into 4-arylbutyrolactones, intermediates for the synthesis of natural products and biological active compounds.

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Communication | Regular issue | Vol 36, No. 11, 1993, pp. 2441 - 2444
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DOI: 10.3987/COM-93-6508
A Facile One-Pot Synthesis of 5-Trifluoromethyl- and 5-Perfluoroalkyloxazoles from N-Alkyl-N-acylamino Acids

Masami Kawase

*Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan


The reaction of N-acyl-N-benzyl-α-amino acids with trifluoroacetic or perfluorocarboxylic anhydride in the presence of pyridine affords 5-trifluoromethyl- or 5-perfluoroalkyloxazoles in high yields.

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Communication | Regular issue | Vol 36, No. 11, 1993, pp. 2445 - 2450
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DOI: 10.3987/COM-93-6509
Reduction of α-Pyrone Derivatives with Borane-Methyl Sulfide Complex

Takeshi Shimizu,* Sayoko Hiranuma, and Tsumoru Watanabe

*The Institute of Physical and Chemical Research, Wako-shi, Saitama 351-0198, Japan


Selective reduction of the 5-carbomethoxy- and 5-carbethoxy-4-hydroxy-2H-pyran-2-one derivatives (5a-11, 19) to yield the 5-hydroxymethyl derivatives (12-18) was accomplished using 1.1 mol equivalent of borane-methyl sulfide complex. Additionally, reduction of the 3-acetyl-4-hdyroxy-2H-pyran-2-one derivatives (23, 26, and 29) with borane-methyl sulfide complex afforded the binary condensed pyrone derivatives (25, 28, and 31) in good yields.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2451 - 2463
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DOI: 10.3987/COM-93-6369
Synthetic Applicatons of 2-Aryl-4-piperidones. IX. Synthesis of Pyrido[1’,2’:1,2]imidazo[4,5-a]quinolizidin-2-one

Anna Diez, Sylvie Mavel, Jean-Claude Teulade, Olivier Chavignon, Marie-Eve Sinibaldi, Yves Troin, and Mario Rubiralta*

*Laboratory of Organic Chemistry, Faculty of Pharmacy, University of Barcelona, Av. de Joan XXIII, s/n, 08028 Barcelona, Spain


The synthesis of the new heterocyclic compound pyrido[1’,2’:1,2]imidazo[4,5-a]quinolizidin-2-one (1), an aza analog of indolo[2,3-a]quinolizidin-2-one, has been effected infour steps from an appropriate 2-aryl-4-piperidone (2), including closure of ring C as the key step.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2465 - 2473
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DOI: 10.3987/COM-93-6381
Reaction of 5-Substituted 2-Amino-2-oxazolines with Ethoxycarbonyl Isothiocyanate

Christian Jarry,* Isabelle Forfar, Jacqueline Thomas, Jean Michel Leger, and Michel Laguerre

*Groupe de Recherche d’Hétérocycles à Potentialités Thérapeutiques, Université de Bordeaux II, 33076 Bordeaux Cedex, France


The reaction of 2-amino-2-oxazolines with ethoxycarbonyl isothiocyanate was found to give only 2,3,6,7-tetrahydro-4H-oxazolo[3,2-a]-1,3,5-triazin-2-one-4-thiones, the structure of which was confirmed by X-ray crystallographic analysis. The direction of attack seems to be related to the more potent nucleophilic character of the endo nitrogen atom in 2-amino-2-oxazoliens. In basic conditions the oxazoline ring can be easily hydrolyzed leading to 1-substituted 1,3,5-triazin-2,4-dione-6-thione.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2475 - 2482
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DOI: 10.3987/COM-93-6453
A New Heterocyclic Ring System: 13H-Benzimidazo[2’,1’:2,3][1,3]thiazino[6,5-b]quinoline

Zoltán Cziáky* and Ferenc Kóródi

*Alkaloida Chemical Co. Ltd., H-4440 Tiszavasvári, POB 1, Hungary


13H-Benzimidazo[2’,1’ :2,3][1,3]thiaziono[6,5-b]quinoline has been synthesized from 2-chloroquinoline-3-carboxaldehydes (1) and 2-mercaptobenzimidazole (2). Subsequent transformations of corresponding 13-hydroxy derivatives are described.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2483 - 2488
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DOI: 10.3987/COM-93-6460
Basicities and Tautomerism of Substituted Methano-bridged Aza[10]annulenes: 10π-Analogues of Pyridine

Alan R. Katritzky,* David E. Leahy, and Balbino Mancheño

*Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, P. O. Box 117200, Gainesville, FL 32611-2046, U.S.A.


pKa values of substituted 2,7-methanoaza[10]annulenes are measured and compared with similarly substituted pyridines. The tautomerism of 2-azabicyclo[4,4,1]undeca-4,6,8,10-tetraen-3-one is discussed.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2489 - 2495
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DOI: 10.3987/COM-93-6466
Total Synthesis of Peruvianine, a Phenolic 7-Oxoaprophine Alkaloid of Telitoxicum peruvianum

Keith T. Buck,* Denise L. Edgren, Geoffrey W. Blake, and Mary D. Menachery*

*Fries and Fries Division, Mallinckrodt, Inc., 110 East 70th Street, Cincinnati, Ohio 45216, U.S.A.


Peruvianine, a phenolic 7-oxoaporphine alkaloid from Telitoxicum peruvianum, has been synthesized via photo-Pschorr cyclization of an aminophenol precursor.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2497 - 2508
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DOI: 10.3987/COM-93-6469
TiCl4 Promoted Ring Expansion Reactions of 5-Hydroxymethyl-2-isoxazoline-2-oxide Methanesulfonates

Kazuho Harada,* Yuko Shimozono, Eisuke Kaji, and Shonosuke Zen

*School of Pharmaceutical Sciences, Kitasato University, Shirokane, Minato-ku, Tokyo 108-8641, Japan


5-Hydroxymetyl-2-isoxazoline-2-oxide methanesulfonates (1) possessing a substituted phenyl ring were treated with TiCl4 to afford either benzofuro[3,2-d]-1,2-oxazines (3) or 4-o-chlorophenyl-4H-1,2-oxazines (4), depending on the nature of the substituents on the phenyl ring of 1. The reaction mechanism of the formation of 3 and 4 is proposed, including 3H-indole-1-oxide zwitterion (B) as a key intermediate.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2509 - 2512
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DOI: 10.3987/COM-93-6474
Synthesis of Methyl 2-(Heteroaryl)propanoates via Palladium-catalyzed Reaction

Takao Sakamoto,* Yoshinori Kondo, Kaoru Masumoto, and Hiroshi Yamanaka

*Pharmaceutical Institute, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan


Methyl 2-(nitrogen-heteroaryl)propanoates were synthesized by the palladium-catalyzed reaction of heteroaryl halides with (E)-1-methoxy-1-trimethylsiloxypropene.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2513 - 2522
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DOI: 10.3987/COM-93-6475
Synthesis of Pyrroloquinoline and Pyrrolonaphthyridine by an Intramolecular Cyclisation Reaction

Isabelle Cardinaud, Alain Gueiffier,* Jean-Claude Debouzy, Jean-Claude Milhavet, and Jean-Pierre Chapat

*Laboratoire de Chimie Organique Pharmaceutique, URA-CNRS, Faculté de Pharamcie, Université Montpellier I, 15, Avenue Charles Flahault, 34060 Montpellier, France


4-Methylthiopyrrolo[1,2-a][1,8]naphthyridine and pyrrolo[1,2-a]quinoline were prepared by an intramolecular cyclisation in acidic media of 1-methylsulfinyl-1-methylthio-2-[3-(2-(1-pyrrolyl)pyridin or phenyl)]ethylene.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2523 - 2530
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DOI: 10.3987/COM-93-6477
Cleavage of the C-20 Ethylidene Side-Chain of Deformyl-Z- and Deformyl-E-geissoschizine Derivatives Utilizing the Modified Polonovski Reaction

Mauri Lounasmaa,* Reija Jokela, Minna Halonen, and Jari Miettinen

*Laboratory for Organic and Bioorganic Chemistry, Technical University of Helsinki, P.O. Box 6100, SF-02150 HUT Espoo, Finland


Cleavage of the C-20 ethylidene side-chain of deformyl-Z-geissoschizine (1) and deformyl-E-geissoschizine (2), and their Na-Boc derivatives (11) and (12), utilizing the modified Polonovski reaction, is described. Mechanistic considerations are presented.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2531 - 2540
Published online:
DOI: 10.3987/COM-93-6478
Structures of Tetra-O-demethylcolchicine, -isocolchicine, and 10-O-Demethylcolchicine Derivatives.

Yoshiki Kashiwada, Li Sun, Hiroshi Tatematsu, Kenneth F. Bastow, and Kuo-Hsiung Lee*

*Division of Medicinal Chemistry and Natural Products, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7360, U.S.A.


During the exhaustive demethylation of both colchicine and isocolchicine analogs, tetra-O-demethyl derivatives with identical structures were produced. Spectral examination (1H-13C long-range COSY nuclear magnetic resonance) of these analogs (5-8) indicated that isocolchicine-type tautomerism is predominant in tetra-O-demethylcolchicine derivatives. Similarly, structures of 10-O-demethylcolchicine derivatives were revised to be an isocolchicine-type shown by formulae (9) and (10).

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2541 - 2547
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DOI: 10.3987/COM-93-6479
Synthesis of 2,3-Dialkoxy-1H-pyrrole via Reduction of Dioxopyrroline with Sodium Hydrosulfite

Takehiro Sano,* Masaharu Seki, Jun Toda, and Yoshisuke Tsuda

*Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan


Reductive of 1H-pyrrole-2,3-dione (3 and 7) with sodium hydrosulfite took place selectively in a 1,4-manner. Methylation of the product with diazomethane gave 1,5-dihydro-3-methoxy-2H-pyrrol-2-one (5 and 8) in good yield. Treatment of the methyl ether (5 or 8) with triethyloxonium tetrafluoroborate caused ethylation of the lactam carbonyl with concomitant deprotonation to give 2,3-dialkoxy-1H-pyrrole (9). This conversion provides a simple synthetic method of 2,3-dialkoxypyrroles.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2549 - 2556
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DOI: 10.3987/COM-93-6480
Synthesis of (±)-2β-Hydroxy-6α-acetoxynortropane

Xue-Feng Pei and Jia-Xiang Shen*

*Laboratory of Medical Chemistry, National Institute of Pharmaceutical Research and Development, P.O.Box 948, Beijing 100083, China


8-Benzyl-6α-chloro-6β-carbonitrile-2,2-ethylenedioxy-8-azabicyclo[3.2.1]oct-3-ene (8) and its C(6) epimer (9) were hydrolyzed to afford 6-ketone (10). Reduction of the ketone (10) with sodium borohydride gave predominantly 6α-ol (14). 2-Ketone (20), obtained from 14 by deprotection followed by hydrogenation and acetylation, was reduced with sodium borohydride to give 2β-ol 21 as the major epimer. Nortropane (24) was prepared from 21 by debenzylation.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2557 - 2564
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DOI: 10.3987/COM-93-6483
Synthesis of 5-Deoxy-5-hydroxyphosphinyl-D-mannopyranoses

Tadashi Hanaya, Kunihiro Hirose, and Hiroshi Yamamoto*

*Department of Chemistry, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530, Japan


The title sugar analogues (13) were synthesized by starting with known methyl (E)-5,6-dideoxy-2,3-isopropylidiene-6-nitro-α-D-lyxo-hex-5-enofuranoside (5a) in six steps through the key intermediate, methyl 5-deoxy-5-dimethoxyphosphinyl-2,3-O-isopropylidene-α-D-mannofuranoside(8a). The products (13) were converted into the corresponding penta-O-acetyl-5-methoxyphosphinyl derivatives (14), whose structures and conformations (mostly 4C1) were established by spectroscopy.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2565 - 2576
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DOI: 10.3987/COM-93-6486
Five New Isoprenoid-substitued Flavonoids, Kanzonols F - J, from Glycyrrhiza uralensis

Toshio Fukai, Junko Nishizawa, Masami Yokoyama, and Taro Nomura*

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


A new isoprenoid-substituted pterocarpan derivative, kanzonol F, a new isoflavanone derivative, kanzonol G, and three new isoflavan derivatives, kanzonols H, I, J, were isolated from Glycyrrhiza uralensis. These structures were elucidated with spectroscopic and/or chemical methods.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2577 - 2589
Published online:
DOI: 10.3987/COM-93-6490
Condensed as-Triazine II: Synthesis of 7-Phenyldihydro- and Tetrahydropyrazino[2,3-e]-as-triazines

Kuan-Han Lee, Bor-Ruey Huang, Yeh-Long Chen, and Cherng-Chyi Tzeng*

*School of Chemistry, Kaohsiung Medical University, 100 Shin Chuen 1st Rd., Kaohsiung 80708, Taiwan, R.O.C.


Certain derivatives of dihydro- and tetrahydropyrazino[2,3-e]-as-triazines were prepared by ring closure of 5,6-diamino-as-triazines with phenylglyoxal in methanol. These 4-azapteridines experience an addition of the alcohol at C(7), and N(8) underwent an unusual methylation under acidic conditions affording the 7-methoxy-8-methyl-6-phenyldihydropyrazino derivative. Regioselective control by the aldehyde-binding reagent, sodium hydrogen sulfite and sodium sulfite, tends to direct the phenyl group to the C(7). Hinsberg reaction of 5,6-diamino-as-triazines with phenacyl bromide proceeded in regiospecific fashion to give the E-form Schiff bases which then isomerize to the corresponding enamines.

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2591 - 2596
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DOI: 10.3987/COM-93-6501
C-Nucleosides. 22. Synthesis of Quinoxaline Acyclo-C-nucleoside

Isamu Maeba,* Masakazu Wakimura, Yasutaka Ito, and Chihiro Ito

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


The synthesis of quinoxaline acyclo-C-nucleoside, 2-[(3S)-3,4-dihydroxybutyl]-3-methylquinoxaline (6), is described. Treatment of furanone glycoisde (1) with 1,2-diaminobenzene gave a mixture of Z- and E- 3-[2-[4-O-benzoyl-(3S)-3-hydroxy-1-butenyl]-3-quinoxalinylmetyl]-1,2,3,4-tetrahydroquinoxalin-2-ones (2a and 2b). Compound (2a) was treated with acetic acid to give three products, Z- and E-2-[4-O-benzoyl-(3S)-3-hydroxy-1-butenyl]-3-methylquinoxalines (3a and 3b) and quinoxalin-2-one (4). Catalytic hydrogenation of 3a,b produced 2-[4-O-benzoyl-(3S)-3-hydroxybutyl]-3-methylquinoxaline (5). Removal of the protecting group in 5 afforded compound (6).

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Paper | Regular issue | Vol 36, No. 11, 1993, pp. 2597 - 2600
Published online:
DOI: 10.3987/COM-93-6505
Condensed Heteroaromatic Ring Systems. XXIII. A Concise Synthesis of Hippadine

Takao Sakamoto,* Akito Yasuhara, Yoshinori Kondo, and Hiroshi Yamanaka

*Pharmaceutical Institute, Tohoku University, Aramaki, Aoba-ku, sendai 980-8578, Japan


Hippadine, a pyrrolophenanthridine alkaloid, was synthesized in 39% overall yield of three steps using the palladium-catalyzed crosscoupling reaction of 2,6-dibromoaniline with (Z)-1-tributylstannyl-2-ethoxyethene as a key step.

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Review | Regular issue | Vol 36, No. 11, 1993, pp. 2601 - 2612
Published online:
DOI: 10.3987/REV-93-457
2-Styrlchromones: Biological Action, Synthesis and Reactivity

William A. Price, Artur M. S. Silva, and José A. S. Cavaleiro*

*Department of Chemistry, Universit y of Aveiro, 3800 Aveiro, Portugal


A brief discussion of the natural occurrence and biological action of 2-styrylchromones is considered in this review; for these compounds and their 3-isoanalogues a thorough description of the successful synthetic strategies is presented. Structural characterization (nmr and mass spectra) and reactivity in Diels-Alder and photooxidation reactons are other important features of 2-styrylchromones to be considered.

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21 data found. 1 - 21 listed