Regular Issue

Vol. 26, No. 11, 1987

26 data found. 1 - 26 listed
Communication | Regular issue | Vol 26, No. 11, 1987, pp.2801-2804
Published online:
DOI: 10.3987/R-1987-11-2801
A New Synthesis of Ambrox and Related Compounds

Manuel González-Sierra, Edmundo A. Rúveda, José T. López, and Manuel J. Cortés

*Facultad de Química, Pontificia Universidad Católica de Chile, Casilla 306, Correo 22, Santiago, Chile

Abstract

The cyclic ether 1, a compounds with an ambergris type odour and related products (10,11) have been prepared from (-)-drimenol (2). The synthesis of 1 is accomplished in ten steps with an overall yield of 19%.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2805-2809
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DOI: 10.3987/R-1987-11-2805
Diastereoselective Synthesis of 2,3-cis-Alkyl-3-oxygenated Piperidine Derivatives by Titanium Mediated Intramolecular Cyclization of α-Aminoacetal-allylsilane System

Shinzo Kano, Tsutomu Yokomatsu, Haruo Iwasawa, and Shiroshi Shibuya

*School of Pharmacy, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan

Abstract

(2S,3S)-2-Alky1-3-oxygenated 5-methylenepiperidines were obtained with high diastereoselectivity by cyclization of N-methoxycarbonyl-N-silylmethallyl-α-alkylaminoacetaldehyde ethyleneacetals with TiCl3 (OPri).

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2811-2816
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DOI: 10.3987/R-1987-11-2811
The Use of Some Activated Nitriles in Heterocyclic Syntheses

Nazario Martín, Conrado Pascual, Carlos Seoane, and Losé L. Soto

*Departamento de Química Orgánica, Facultad de Química, Universidad Complutense de Madridas, Ciudad Universitaria, E-28040 Madrid, Spain

Abstract

The recently reported synthesis of a variety of 4H-pyrans from cinnamonitriles is reinvestigated and revised structures are given. New reaction products are also described.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2817-2822
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DOI: 10.3987/R-1987-11-2817
A Regioselective and Common Synthetic Method of Dihalogenoindoles and Its Application for the Total Syntheses of Marine Alkaloids, 4,6-Dibromo-, 4,6-Dibromo-2-methyl-, and 3,4,5-Tribromoindole

Toshiharu Ohta, Yoshinori Yamato, Hiroko Tahira, and Masanori Somei

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

Abstract

A regioselective and common synthetic method for indoles carrying two different kinds of halogens was developed and applied successfully to the total syntheses of marinealkaloids, 4,6-dibromo- and 3,4,5-tribromoindole. The first total synthesis of 4,6-dibromo-2-methylindole is also reported.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2823-2828
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DOI: 10.3987/R-1987-11-2823
A Convenient Synthetic Method for 4-Nitro-1,3,4,5-tetrahydrobenz[cd]indoles and Its Application for an Alternative Synthesis of (±)-6,7-Secoagroclavine

Masanori Somei, Fumio Yamada, Hiroyuki Ohnishi, Yoshihiko Makita, and Mikako Kuriki

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

Abstract

Various 4-substituted indoles are prepared and a simple synthetic method for 4-nitro-1,3,4,5-tetrahydrobenz[cd]indole derivatives is elaborated using intramolecular Michael addition reaction as a key step. Syntheses of new tetracyclic 4H-indolo[6,5,4-cd] indole derivatives and (±)-6,7-secoagroclavine are also included.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2829-2834
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DOI: 10.3987/R-1987-11-2829
Chemoselective Reactions of Ultrasonically Dispersed Potassium with Some Brominated Hydrothiophene S,S-Dioxides

Ta-shue Chou and Mei-Man Chen

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

Abstract

The reactions of ultrasonically dispersed potassium (UDP) with I-bromo-2-sulfolenesr resulted in chemoselective deprotonetion at the C-5 position leading to the elimination-dimerization products. The possible C-S bond and C-Br cleavage reactions were not detected. The reaction of UDP with 3,4-dibromosulfolane resulted in dehydrobro mination and double dehydrobromination.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2835-2840
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DOI: 10.3987/R-1987-11-2835
Methylenation of Some Lycoctonine-type C19-Dithrpenoid Alkaloids: Partial Synthesis of Delbruline, and Elatine

S. William Pelletier, Haridutt K. Desai, Palaniappan Kulanthaivel, and Balawant S. Joshi

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

Abstract

Delbruline (5), delbrusine (6). elatine (1) and certain other atkatoids containing a methylenedioxy group a t the C(7)-C(8) position have been synthesized by the reaction of fomaldehyde or diethoxymethans with suitabte alkaloid aubstratea under carefully controlled conditions.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2841-2844
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DOI: 10.3987/R-1987-11-2841
Synthesis of (S)-N-(Benzyloxy)-4-acetoxymethyl-2-azetidinone, Potential Intermediate for Carbapenem Antibiotics, by Chemomicrobiological Approach

Haruo Yamada, Hajime Sugiyama, and Masahiro Kajiwara

*Department of Medicinal Chemistry, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan

Abstract

(R)-Ethyl 4-t-butoxy-3-hydroxybutanoate, which was prepared by baker’s yeast reduction of ethyl 4-t-butoxy-3-oxobutanoate, was converted to (R)-3-hydroxybutyrolactone. After cleavage of the lactone ring with N-benzyloxyamine, β-lactam cyclization of the hydroxamate was carried out by Mitsunobu procedure with complete inversion of configuration at C-3 to give (S)-N-(benzyloxy)-4-acetoxymethyl-2-azetidinone. The corresponding (R)-azetidinone was also synthesized from natural (S)-malic acid via (S)-3-hydroxybutyrolactone.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2845-2848
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DOI: 10.3987/R-1987-11-2845
Revised Structure of Nobotanin B, a Dimeric Ellagitannin of Tibouchina semidecandra

Takashi Yoshida, Kumiko Haba, Tetsuro Shingu, and Takuo Okuda

*Faculty of Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Okayama 700-8530, Japan

Abstract

The structure of nobotanin B, a dimeric ellagitannin of Tibouchina semidecandra, has been revised to 9 on the basis of structural analysis of a partial hydrolysate.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2849-2851
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DOI: 10.3987/R-1987-11-2849
Rearrangement of N-(p-Toluenesulfonyloxy)-2-pyrrolidinone

Atanu Biswas and Marvin J. Miller

*Department of Chemistry, University of Notre Dame, Notre Dame, IN 46556, U.S.A.

Abstract

Base induced rearrangement of N-(p-toluenesulfonyloxy)-2-pyrrolidinone provides 3-(p-toluenesulfonyloxy)-2-pyrrolidinone by an apparent nitrogen analog of the Favorskii rearrangement.

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2853-2856
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DOI: 10.3987/R-1987-11-2853
Reaction of 2,4-Diphenyl-1,3,5-triazine Derivatives with Nucleophiles

Hiroshi Yamanaka, Setsuya Ohba, and Shoetsu Konno

*Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980-8578, Japan

Abstract

The addition of hydrogen cyanide to 2,4-diphenyl-1,3,5-triazine (1) followed by spontaneous oxidation of the adduct gave 4,6-diphenyl-1,3,5-triazine-2-carbonitrile (4) in considerable yield. Similarly, 1 reacted with various active methylene compounds in the presence of sodium hydride to give the corresponding 2-substituted 4,6-diphenyl-1,3,5-triazines (8a-c). Additionally, the condensation of 2-chloro-4,6-diphenyl-1,3,5-triazine (2) with benzaldehyde in the presence of 1,3-dimethylbenzimidazolium iodide under basic conditions, gave the corresponding 2-benzoyl-1,3,5-triazine (9).

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2857-2860
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DOI: 10.3987/R-1987-11-2857
Reaction of 1-Benzopyrylium Salts with Trialkyl Phosphite: Formation of 2,4-Disubstituted 1-Benzopyran Derivatives

Hideharu Iwasaki and Kin-ya Akiba

*Department of Chemistry, Faculty of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan

Abstract

Reaction of 1-benzopyrylium perchlorate (1) with triethyl phosphite gave 2H-benzopyran-2-phosphonate (2) in good yield. Deprotonation of 2 with sec-BuLi at-78 °C followed by addition of aromatic aldehydes gave exomethylene compound (4). Reaction of ketene silyl acetal (7) with 2 -substituted 1-benzopyrylium salt (6), generated in situ from 4 by addition of CF3S03H, afforded the corresponding 2,4-disubstituted 1-benzopyran (8).

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Communication | Regular issue | Vol 26, No. 11, 1987, pp.2861-2864
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DOI: 10.3987/R-1987-11-2861
Thermal Rearrangements of 8-Aza- and 8-Oxa-3,4-diazatricyclo-[5.1.0.02.6]oct-4-enes

Jyoji Kurita, Hiroichi Sakai, and Takashi Tsuchiya

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

Abstract

Flash vacuum pyrolysis of the 8-oxa-3,4-diazatricyclo-[5.1.0.02,6]oct-4-enes (7) resulted in rearrangement to give the - 1-amino-2-formylpyrroles (7), presumably via the 1,4,5-oxadiazocines (14)whereas that of the 8-aza analogues (8) gave the 3a,6a-dihydropyrrolo[2,3-clpyrazoles (12) by a different type of rearrangement.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2865-2869
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DOI: 10.3987/R-1987-11-2865
Synthesis of 1-Methyl-2-(2-oxazolyl)-5-nitroimidazole

Abbas Shafiee, Tayebeh Ebrahimi-Bibalan, Mohammad E. Bakhshi-Dezfouli, and Alireza Ghanbarpour

*Department of Chemistry, College of Pharmacy, Tehran University, Tehran 14, Iran

Abstract

1-Methyl-2-(2-oxazoly1)-5-nitroimidazole (4) was prepared from methyl 1-methyl-5-nitroimidazole-2-carboxylate (5) . The reaction of compound 5 with 2-aminoethanol gave N-(2-hydroxyethy1)-1-methyl-5-nitroimidazole-2-carboxamide (7). Treatment of 7 with thionyl chloride gave 8 which was cyclized to afford 9 by treatment with a base. Oxidation of 9 with nickel peroxide afforded compound 4.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2871-2875
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DOI: 10.3987/R-1987-11-2871
Studies on Rutaceae: Part VII — An Interesting Rearrangement of the Rare Epoxycoumarin, Micromelumin, to the Linear Furanocoumarin, Psoralen

Julie Banerji, Anup K. Das, and Biswanath Das

*Chemistry Department, University College of Science, 92 Acharya Prafulla Chandra Road, Calcutta-700009, India

Abstract

Boron trifluoride etherate treatment of 7-methoxy -6-ζ-butyrolactone-3’ -methyl-3’ ,4’ -epoxycoumarin (micromelumin), a constituent of Micromelum Pubescens Blume (Rutaceae), afforded an interesting rearranaed produot, psoralen, in addition to 7-methoxycoumarinyl-6-tetronic acid derivative.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2877-2886
Published online:
DOI: 10.3987/R-1987-11-2877
Biological Formation and Chemical Synthesis of 2-Amino-3,6-dihydro-3-methyl-7H-imidazolo[4,5-f]quinolin-7-one, the Major Metabolite of the Dietary Carcinogen 2-Amino-3-methyl-3H-imidazolo[4,5-f]quinoline (IQ) by Normal Intestinal Bacteria

Mohammad Bashir, David G. I. Kingston, Robert J. Carmen, Roger L. Vn Tassell, and Tracy D. Wilkins

*Department of Chemisry, Virginia Polytecnic Institute and State University, Blacksburg, Virginia 24061-0212, U.S.A.

Abstract

2-Amino-3,6-dihydro-3-methyl-7H-imidazolo[4,5-f]quinolin-7-one (2) has been synthesized from 6-bromo-5-nitroquinoline in seven steps. Biological formation of 2 from IQ(1) involves the addition of water from the medium, followed by oxidation.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2887-2894
Published online:
DOI: 10.3987/R-1987-11-2887
Bis(4-methyl-2-thiazolyl)guanidines. Preparation and Physicochemical Properties

Reiko Yoda and Yoshikazu Matsushima

*Faculty of Pharmaceutical Sciences, Kyoritsu College of Pharmacy, 1-5-30, Shiba-koen, Minato-ku, Tokyo 105-8512, Japan

Abstract

Eighteen N-substituted and N,N-disubstituted N’, N”-bis (4-methyl-2-thiazolyl) guanidin were prepared by the reaction of N,N’-bis(4-methyl-2-thiazolyl)-S-methylisothiourea with amines. Their ultraviolet, infrared, 1H- and 13C-nuclear magnetic resonance and mass spectral data supported the structures.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2895-2904
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DOI: 10.3987/R-1987-11-2895
New Diterpenoid Alkaloids from Delphinium staphisagria Linné

Samir A. Ross, Haridutt K. Desai, and S. William Pelletier

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

Abstract

Delestaphidine (7) and neotinine (8), two new C19-diterpenoid alkaloids, and α-oxodelphinine (9) have been isolated from the seeds of Delphinium staphisagria. The structures of these alkaloids were determined on the basis of spectral data, correlation with alkaloids of establishad structures, preparation of certain derivatives and by synthesis. α-Oxodelphinine has not been isolated from a natulal source previously. N-Deethyldelphisine (10) and N-deethyldelstaphidine (11), two new, synthetic diterpenoid alkaloide, have been prpared by KMnO4 oxidation of delphisine. Oxidative cyclization of delphisine with alkaline potassium ferricyanide gave delstaphinine (6).

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2905-2910
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DOI: 10.3987/R-1987-11-2905
The Regioselectivity of Amination of Certain 4-Dimethylaminopyridines

Michael P. Groziak and Laura M. Melcher

*Roger Adams Laboratory, School of Chemical Sciences, University of Illinois, 1209 West California Street, Urbana, IL 61801-3731, U.S.A.

Abstract

Under the homogeneous aminating conditions of KNH2 in NH3, 3-bromo-4-dimethylaminopyridine 2 affords a mixture of 2-amino-5-bromo-4-dimethylaminopyridine 3 and 3-amino-4-dimethylaminopyridine 4, along with the product of debrominatian, 4-dimethylaminopyridine 1. Compound 3 was debrominated with Zn in HOAc to afford 2-amino-4-dimethylaminopyridine 5. The regioselectivity observed for the homogeneous amnation of 2 is precisely that predicted by an analysis of the lowest unoccupied frontier molecular orbital coefficients.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2911-2920
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DOI: 10.3987/R-1987-11-2911
Azetidinone Imides

Douglas O. Spry, Nancy J. Snyder, Anita R. Bhala, Carol E. Pasini, and Joseph M. Indelicato

*Chemical Process Research and Development Division, Lilly Corporate Center, Lilly Reserach Laboratories, Eli Lilly & Company, Indianapaolis, IN 46285-4813, U.S.A.

Abstract

The synthesis of acetyl and Boc azetidinone imides is described

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2921-2939
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DOI: 10.3987/R-1987-11-2921
Facile Synthesis of Some Oxazolopyridines and Their N-Oxides via Intramolecular Cyclization

Yoshinobu Tagawa and Yoshinobu Goto

*Faculty of Pharmaceutical Sciences, Fukuoka University, Nakamura, Jonan-ku, Fukuoka, 814-0180, Japan

Abstract

A convenient synthesis of 3-methylisoxazola[4,5-b]-pyridine 2, 2-methyloxazolo[4,5-b]pyridine 4 and their N-oxides (12, 11 and 18) is reported. The configurations of the oximes used for the synthesis of the compounds described above are discussed through chemical and spectral studies.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2941-2944
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DOI: 10.3987/R-1987-11-2941
A New Heterocyclic System from Salol and Phenylacetic Acid

Lina G. Sardesai, Shashikumar K. Paknikar, Robert B. Bates, Teruna J. Siahaan, Vinayak V. Kana, and Prasana K. Mishra

*Department of Chemisitry, Goa University, Bombolim, Goa-403 005, India

Abstract

Salol when heated with phenylacetic aoid gives a compound with a novel heterocyclic system. A sequence by which this new compound may arise is postulated and supported by experiment.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2945-2948
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DOI: 10.3987/R-1987-11-2945
An Alternative Procedure for the Preparation of 4-Benzylisoquinolines from Isoquinoline

Robin D. Clark

*Institute of Organic Chemistry, Syntex Research, Palo Alto, California 94304, U.S.A.

Abstract

Addition of lithiated N,N-diethyl-o-toluamide to isoquinoline gave an adduct which was treated with benzyl chlorides to afford 4-benzylisoquinolines in yields of 60-78%.

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2949-2957
Published online:
DOI: 10.3987/R-1987-11-2949
Quinolizidines. XXIII. An Alternative Synthetic Route to Benzo[a]quinolizidine-type Alangium Alkaloids from Ethyl Cincholoiponate

Tozo Fujii, Masashi Ohba, Kaori Shimohata, and Shigeyuki Yoshifuji

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

Abstract

The trans lactam acid (+)-XX was isolated in good yield in the form of the 4-methoxybenzyl ester (+)-XXV from an equilibrated 66 : 34 mixture of the trans and cis isomers [(+)-XX and (+)-XIX], which was obtained by thermal cis-trans isomerization of the cis lactam acid (+)-XIX at 190°C for 15 min. Catalytic hydrogenolysis of (+)-XXV with 10% Pd-4 and H2 gave (+)-XX in 97% yield. This made it possible to establish an alternative synthetic route to all of the I-IV-type Alangium alkaloids from ethyl cincholoiponate [(+)-XVI] , a degradation product of the Cinchona alkaloid cinchonine [(+)-V].

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Paper | Regular issue | Vol 26, No. 11, 1987, pp.2959-2962
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DOI: 10.3987/R-1987-11-2959
Three New Coumarins from Leaves of Murraya paniculata

Chihiro Ito and Hiroshi Furukawa

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

Abstract

Three new coumarins named isomurralonginol nicotinate (1) , panial (3). and cis-osthenon (4) were isolated from the leaves of Murraya paniculata collected in Iriomote Island, Okinawa.

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Review | Regular issue | Vol 26, No. 11, 1987, pp.2963-2982
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DOI: 10.3987/R-1987-11-2963
Pyridinium Salts: Luminescent Spectroscopy and Photochemistry

Michail I. Knyazhanskii, Yakov R. Tymyanskii, Vladimir M. Feigelman, and Alan R. Katritzky

*Center for Drug Discovery, College of Pharmacy, University of Florida, Gainesville, Florida 32611-7200, U.S.A.

Abstract

The electronic absorption and emission properties of pyridinium cations are summarized and rationalized in terms of their molecular structure. Photochemical processes of pyridinium salts are surveyed vith particular reference to cyclization reactions and the effect on reaction modes and rates of structural variations. The various photophysical and photochemical processes are formulated in a general scheme of photoinduced excitation and relaxations.

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26 data found. 1 - 26 listed