Regular Issue

Vol. 45, No. 10, 1997

26 data found. 1 - 26 listed
Communication | Regular issue | Vol 45, No. 10, 1997, pp.1869-1872
Published online:
DOI: 10.3987/COM-97-7893
Diels-Alder Reaction of Ligustilide Giving Levistolide A and Tokinolide B

Yoshimitsu Ogawa, Yoshikazu Mori, Masao Maruno, and Takeshi Wakamatsu*

*Central Research Laboratory, Tsumura & Co., 3586 Yoshiwara, Ami-machi, Inashiki-gun, Ibaraki, 300-11, Japan

Abstract

Naturally occurring levistolide A (1) and tokinolide B (2) were first synthesized by a Diels-Alder reaction of ligustilide (3) under the several reaction conditions. The dimer (2) was converted into the thermodynamically stable dimer (1) at 200 °C. The caluculation of HOMO and LUMO of 3 was also carried out by MNDO/PM3 method to explain the regioselectivity.

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Communication | Regular issue | Vol 45, No. 10, 1997, pp.1873-1878
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DOI: 10.3987/COM-97-7896
1,3-Dipolar Cycloaddition Behavior of Pyrazolone N,N-Dioxides toward Epoxynaphthalene. Effective Secondary N···O Interaction between Addends

Yasuyuki Yoshitake, Masashi Eto, and Kazunobu Harano*

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

Abstract

Cycloaddition of pyrazolone N,N-dioxides (1) with epoxynaphthalene (2a) gave endo 1,3-dipolar cycloadduct. The origin of the high endo selectivity was explored by MO analysis of the transition structure. Ab initio calculation at several levesl indicates that the orientation complex (OC) forms prior to the formation of the transition state (TS). The interaction between the oxygen of 2a and the nitrogen of the >N→O group of 1 binds two addends together in both OC and TS.

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Communication | Regular issue | Vol 45, No. 10, 1997, pp.1879-1882
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DOI: 10.3987/COM-97-7897
Photolysis of Dimethyl 2-Diazo-6-oxo-2,6-dihydroazulene-1,3-dicarboxylate and Methyl 3-Cyano-2-diazo-6-oxo-2,6-dihydroazulene-1-carboxylate in Tetrahydrofuran

Shih-Jue Lin, Shuan-Ya Jiang, Tian-Chyuan Huang, Ping Kao, Pai-Feng Tsai, Hitoshi Takeshita, Yun-Shan Lin,* and (the late) Tetsuo Nozoe

*Department of Chemistry, Tamkang University, Tamsui, 25137, Taiwan, R.O.C.

Abstract

Upon photolysis in tetrahydrofuran, dimethyl 2-diazo-6-oxo-2,6-dihydroazulene-1,3-dicarboxylate afforded a crown-type origomerized cyclic ether in very low yield, but the major products were the C-H insertion products such as 2,6-disubstituted azulenedicarboxylate, whereas methyl 3-cyano-2-diazo-6-oxo-2,6-dihydroazulene-1-carboxylate gave, similar to 1,3-dicyano-2-diazo-2,6-dihydroazulen-6-one, oligomeric crown ethers predominantly, suggesting that a steric factor played a crucial role in their formations.

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Communication | Regular issue | Vol 45, No. 10, 1997, pp.1883-1889
Published online:
DOI: 10.3987/COM-97-7902
(1'S,4S)-2-Aryl-4-(1'-hydroxybenzyl)-4,5-dihydrooxazole as a Useful Chiral Auxiliary for the Synthesis of β-Amino Acids and β-Lactams in a Highly Stereoselective Manner

Makoto Shimizu, Shingo Maruyama, Yasuhiro Suzuki, and Tamotsu Fujisawa*

*Department of Chemistry for Materials, Mie University, 1515 Uehama-cho, Tsu, Mie 514-5807, Japan

Abstract

(1’S,4S)-2-Aryl-4-(1’-hydroxybenzyl)-4,5-dihydrooxazole prepared from (1S,2S)-2-amino-1-phenylpropane-1,3-diol has been found to be a useful chiral auxiliary for the stereoselective synthesis of β-lactams and β-amino acids in the reaction of imine-ester enolate condensation or 1,4-addition of lithium amides to α,β-unsaturated esters.

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Communication | Regular issue | Vol 45, No. 10, 1997, pp.1891-1894
Published online:
DOI: 10.3987/COM-97-7911
Syntheses of Novel Group 15 and 16 Thieno[2,3-b]-, Thieno[3,4-b]-, and Thieno[3,2-b]-heteroles

Shuji Yasuike, Jyoji Kurita, and Takashi Tsuchiya*

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

Abstract

Group 15 (P, As and Sb) and group 16 (S, Se, and Te) thieno[2,3-b]- (1), thieno[3,4-b]- (2), and thieno[3,2-b]heteroles (3) were prepared from the corresponding 1,4-dilithium intermediates, derived from (Z)-(β-bromo-β-trimethylsilylvinyl)thiophenes (6), (10), and (13) by treatment with tert-butyllithium, respectively. These thienoheteroles obtained are novel fused heterocyclic ring systems, except for thienothiophenes and thienoselenophenes.

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Communication | Regular issue | Vol 45, No. 10, 1997, pp.1895-1898
Published online:
DOI: 10.3987/COM-97-7926
Formal Synthesis of (-)-Syringolide 1 Starting from D-Xylose Based on a Biomimetic Strategy

Hidemi Yoda,* Miho Kawauchi, Kunihiko Takabe, and Ken Hosoya

*Department of Molecular Science, Faculty of Engineering, Shizuoka University, 3-5-1 Johoku, Hamamatsu 432-8561, Shizuoka, Japan

Abstract

An expeditious and practical synthetic process for a nonproteinaceous elicitor, (-)-syringolide 1, has been developed in a short number of steps utilizing the putative biosynthetic pathway by featuring the elaboration of the protected D-xylose as a starting material.

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Communication | Regular issue | Vol 45, No. 10, 1997, pp.1899-1902
Published online:
DOI: 10.3987/COM-97-7930
Syntheses of Novel Dithieno[2,3-b;3’,2’-f]- and Dithieno[3,4-b;3’,4’-f]heteroepines Containing Group 14, 15, and 16 Heavier Elements

Shuji Yasuike, Fumio Nakashima, Jyoji Kurita, and Takashi Tsuchiya*

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

Abstract

The dithieno[2,3-b;3’,2’-f]- (3) and dithieno[3,4-b;3’,4’-f]heteroepines (4) containing Group 14 (Si, Ge, and Sn), Group 15 (P, As, Sb, and Bi) and Group 16 (S, Se, and Te) elements were prepared from 2-bromo-3-iodothiophene and 3-bromo-4-iodothiophene via four steps, respectively, and thermal stabilities of these novel heterocyclic ring systems were examined.

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Communication | Regular issue | Vol 45, No. 10, 1997, pp.1903-1906
Published online:
DOI: 10.3987/COM-97-7939
A Short and Efficient Synthetic Process to Enantiomerically Pure (+)-Syributin 1

Hidemi Yoda,* Miho Kawauchi, Kunihiko Takabe, and Ken Hosoya

*Department of Molecular Science, Faculty of Engineering, Shizuoka University, 3-5-1 Johoku, Hamamatsu 432-8561, Shizuoka, Japan

Abstract

For the synthesis of (+)-syributin 1 produced by bacteria which expresses the avrD gene, a simple and practical synthetic route is described in a short number of steps and high overall yield featuring the elaboration of D-arabinofuranose derivative.

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Paper | Regular issue | Vol 45, No. 10, 1997, pp.1907-1912
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DOI: 10.3987/COM-97-7913
An Efficient Synthesis of Novel Spirodeoxoartemisinin with 2-Pyrazoline Ring

Mankil Jung* and Seokjoon Lee

*Department of Chemistry, Yonsei University, Seoul 120-749, Korea

Abstract

Water-soluble, novel spirodeoxoartemisinin (10a) with 2-pyrazoline ring at C-11 was prepared from artemisinic acid (3) in four steps.

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Paper | Regular issue | Vol 45, No. 10, 1997, pp.1913-1919
Published online:
DOI: 10.3987/COM-97-7915
Reaction of N-Trimethylsilylmethyliminodithiocarbonate with Carbonyl Compounds: Synthetic Equivalent of Alkylthionitrile Ylide

Makoto Oba, Masahiro Yoshihara, Jun Nagatsuka, and Kozaburo Nishiyama*

*Department of Material Science and Technology, Tokai University, 317, Nishino, Numazu, Shizuoka 410-0395, Japan

Abstract

Diethyl N-trimethylsilylmethyliminodithiocarbonate (2) prepared by an addition of ethanethiol toward trimethylsilylmethyl isothiocyanate (1) followed by S-ethylation was found to react with some carbonyl compounds in the presence of fluoride ion to afford the oxazoline derivatives (4) in fair yields after a treatment of the reaction mixture with silica gel, where the dithiocarbonate derivative (2) formally served as alkylthionitrile ylide equivalent in the reaction sequence.

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Paper | Regular issue | Vol 45, No. 10, 1997, pp.1921-1927
Published online:
DOI: 10.3987/COM-97-7916
A Convenient Procedure for the Synthesis of 2,3-Dihydro-1,4-dithiaphenanthrene Derivatives

Gemma Esteban, Berta López, Joaquín Plumet,* and Alberto del Valle

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

Abstract

A convenient method for the synthesis of 2,3-dihydro-1,4-dithiaphenanthrene derivatives starting from S,S-acetals of tetralones is described. A feasible mechanism for this transformation is also proposed.

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Paper | Regular issue | Vol 45, No. 10, 1997, pp.1929-1935
Published online:
DOI: 10.3987/COM-97-7922
Investigation of the Reaction of 5-Bromonicotinic Acid with Certain Arylacetonitriles and LDA in THF

Anlai Wang and Edward R. Biehl*

*Southern Methodist University, P.O.Box 750314, Dallas, Texas 75275-0314, U.S.A.

Abstract

The reaction of 5-bromonicotinic acid with various arylacetonitriles and LDA yields the corresponding 5-(α-arylcyanomethyl)nicotinic acids in good yields. These cyano acids can be oxidatively decyanated to the respective 5-aroylnicotinic acid in excellent yields.

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Paper | Regular issue | Vol 45, No. 10, 1997, pp.1937-1944
Published online:
DOI: 10.3987/COM-97-7924
Synthesis of 2-Aroylmethylquinolin-4-ones via the Addition Reaction of ortho-Nitrobenzoylketene to 1-Aryl-1-trimethylsilyloxyethylenes

Jun Toda, Toshiaki Saitoh, and Takehiro Sano*

*Showa Pharmaceutical University, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan

Abstract

Catalytic hydrogenation of 1-aryl-5-(2-nitrophenyl)pentane-1,3,5-triones A over 10% Pd-C caused selective reduction of the nitro group with concomitant cyclization to give 2-aroylmethylquinolin-4-ones B. This provides a simple method of quinolin-4-one synthesis.

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Paper | Regular issue | Vol 45, No. 10, 1997, pp.1945-1953
Published online:
DOI: 10.3987/COM-97-7927
Novel Aspects of the Silver Carbonate Promoted Reaction of Hydrazonyl Chlorides with Homoallylic And Homopropargylic Alcohols

Gianluigi Broggini, Luisa Garanti, Giorgio Molteni, and Gaetano Zecchi*

*Dipartimento di Chimica Organica e Industriale, Universita di Milano, via Golgi 19, I-20133 Milano, Italy

Abstract

The title reaction gives, in addition to trivial side-products, both ring-closed products (3, 4, 14, and 15) and open-chain products (5-8, and 16). The role of the silver ion and the mechanistic possibilities for the formation of the various kinds of products are discussed.

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Paper | Regular issue | Vol 45, No. 10, 1997, pp.1955-1965
Published online:
DOI: 10.3987/COM-97-7928
Isolation and Structure of Raveyine, a Novel Norditerpenoid Alkaloid from Consolida raveyi(Boiss) Schröd.

Ali H. Meriçli, Filiz Meriçli, Vildan Seyhan, Ayhan Ulubelen, Haridutt K. Desai, Balawant S. Joshi, Quincy Teng, 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

From the aerial parts of Consolida raveyi (Boiss) Schröd., a new norditerpenoid alkaloid designated as raveyine has been isolated along with the known alkaloids ajaconine, azitine, chellespontine and isoatisine. The structure of raveyine (4) was determined on the basis of homonuclear 1H decoupled 13C, DEPT, 2D 1H phase sensitive COSY, TOCSY, ROESY, 1H-13C HMQC, HMQC-clean TOCSY and HMBC NMR spectral studies.

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Paper | Regular issue | Vol 45, No. 10, 1997, pp.1967-1978
Published online:
DOI: 10.3987/COM-97-7931
Synthesis and Aromatization of Dihydropyrimidines Structurally Related to Calcium Channel Modulators of the Nifedipine-Type

Jean Jacques Vanden Eynde, Nancy Audiart, Valérie Canonne, Sophie Michel, Yves Van Haverbeke, and C. Oliver Kappe*

*Institute of Organic Chemistry, Karl-Franzens-University Graz, Heinrichstr. 28, A-8010 Graz, Austria

Abstract

A series of 4-substituted ethyl 2-methoxy-6-methyl-1,4-dihydropyrimidine-5-carboxylates has been synthesized and was successfully aromatized to the corresponding pyrimidines with various oxidizing reagents. O-Demethylation of such pyrimidines provides a simple route to pyrimidinone derivatives which are otherwise difficult to obtain.

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Note | Regular issue | Vol 45, No. 10, 1997, pp.1979-1988
Published online:
DOI: 10.3987/COM-96-7676
A New Route to Quinolone and Indole Skeletones via Ketone- and Ester-Imide Cyclodehydration Reactions

Guncheol Kim* and Gyochang Keum

*Organic Chemistry Division, Hanhyo Institutes of Technology, Jeonmin-Dong 461-6, Yusong-gu, Taejon 305-390, Korea

Abstract

Ketone-imide cyclodehydration reactions of aromatic succinimide and phthalimide (7, 8) have aforded quinolone acids (11, 12). Further transformation of the acids provided the corresponding esters (13, 14) and vinylogous urethanes (9, 10). Similarly, ester-imide cyclodehydration reactions of aromatic imide esters (19, 20) have afforded indole acids (23, 24).

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Note | Regular issue | Vol 45, No. 10, 1997, pp.1989-1997
Published online:
DOI: 10.3987/COM-97-7877
Synthesis and NMR-Investigation of Annelated Pyrrole Derivatives

Helmut Spreitzer,* Wolfgang Holzer, Christiane Puschmann, Andrea Pichler, Angelika Kogard, Klaus Tschetschkowitsch,Tatjana Heinze, Sabina Bauer, and Nejati Shabaz

*Institute of Pharmaceutical Chemistry, University of Vienna, Währinger Strasse 10, A-1090 Vienna, Austria

Abstract

The synthesis of annelated pyrrole, namely isoindole derivatives by reaction of α,β-unsaturated ketones, benzo- and naphthoquinone monoketals with tosylmethyl isocyanide is described. Moreover, detailed NMR spectroscopic studies (1H, 13C) with the title compounds are presented.

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Note | Regular issue | Vol 45, No. 10, 1997, pp.1999-2005
Published online:
DOI: 10.3987/COM-97-7883
Formation of Thiazole and 1,3-Thiazolidine Sulfoxide from Pyrolysis of a Thiolsulfinate

Heduck Mah, Kee Dal Nam, and Hoh-Gyu Hahn*

*Organic Chemistry Laboratory, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 136-791, Korea

Abstract

The mechanistic study on the prolytic transformation of a thiolsulfinate (2) is described. The reactive intermediates sulfenic acid (6) and thioaldehyde (8) were formed resulting from S-S bond cleavage and a hydrogen transfer from sulfenyl to sulfinyl moiety. A stereospecific cyclization of 6 to cis-sulfoxide (4) was observed, which arouse from the geometrical requirements of a planar transition state for the reacting bonds and atoms in the sigmatropic rearrangement. In the transformation of 8 to thiazole (9), the amide carbonyl group facilitated the elimination of a neighboring proton and enabled to furnish the nucleophilic attack of a thiocarbonyl sulfur at β to internal carbonyl group to yield thiazole (9).

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Note | Regular issue | Vol 45, No. 10, 1997, pp.2007-2013
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DOI: 10.3987/COM-97-7884
Synthesis of Vinca Alkaloids and Related Compounds LXXXVIII. Highly Enantioselective Synthesis of (+)-Vincamine

Tamás Nagy, Lajos Szabó, György Kalaus, and Csaba Szántay*

*Institute for Organic Chemistry, Technical University Budapest, H-1521 Budapest, P.O. Box 91Gellért tér 4, Hungary

Abstract

The interaction of the chiral malonic ester derivative (5) with formaldehyde and Wenkert enamine (1) yields the tetrahydropyranoindoloquinolizine (6), from which a highly enantioselective synthesis of the commercially important alkaloid (+)-vincamine (12) was achieved.

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Note | Regular issue | Vol 45, No. 10, 1997, pp.2015-2021
Published online:
DOI: 10.3987/COM-97-7887
The Preparation of 1-Nonsubstituted and 1-Methyl- (and Ethyl)-1,4-dihydro-4-oxo- 3-quinolinesulfonamides from 4-Chloro-3-quinolinesulfonamides

Leszek Skrzypek and Andrzej Maslankiewicz*

*Department of Organic Chemistry, The Medical University of Silesia, Jagiellonska Str. 4, 41-200 Sosnowiec, Poland

Abstract

4-Chloro-3-quinolinesulfonamides (1) were hydrolysed to 1,4-dihydro-4-oxo-3-quinolinesulfonamides (2) with boiling 18% hydrochloric acid. N-Alkyl-1,4-dihydro-4-oxo-3-quinolinesulfonamides (3) were prepared by quaternization of compounds (1) with dialkyl (methyl or ethyl) sulfate followed by hydrolysis of the quinolinium salt (4) formed.

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Note | Regular issue | Vol 45, No. 10, 1997, pp.2023-2031
Published online:
DOI: 10.3987/COM-97-7888
Preparation of Enamines from the Condensation of Glycine Esters with Nitro-Heterocyclic Aldehydes

Hugo Cerecetto, Rossanna Di Maio, Mercedes González, and Gustavo Seoane*

*Cátedra de Química Orgánica, Facultad de Química, Universidad de la República, Avda. General Flores 2124, Casilla de Correo 1157, C. P. 1180 Montevideo, Uruguay

Abstract

In order to prepare the imine derived from condensation of glycine ethyl ester and 5-nitrothiopene-2-carboxaldehyde, another compound was obtained instead. This product was the enamine, ethyl 2-amino-3-(5-nitro-2-thienyl)-2-propenoate, resulting from the condensation between the methylene of the glycine derivative and the heterocyclic carbonyl group. The reactivity of related amines and heterocyclic aldehydes was studied in order to get more insight about the mechanism of enamine formation. It was found that the nitro-heterocyclic group and the easy of enolization of the aminoacidic ester played an important role.

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Note | Regular issue | Vol 45, No. 10, 1997, pp.2033-2039
Published online:
DOI: 10.3987/COM-97-7891
Regioisomers in the Photodimerization of Acridizinium Bromide

Christoph Lehnberger, Dieter Scheller, and Thomas Wolff*

*Technische Universitat Dresden, Institut fur Physikalischce Chemie und Elektrochemie, Mommsenstr. 13, D-01062 Dresden, Germany

Abstract

Products of the photodimerization of acridizinium bromide (1) were analyzed by means of 1H NMR spectroscopy. Upon irradiation in solution and in the solid state four distinct isomeric photodimers were identified, two of which may exist in enantiomeric forms which could not be distinguished. Solubilization of 1 in anionic micellar solutions affected the regioselectivity of the photodimerization: as compared to a homogeneous aqueous solution the yield of dimers exhibiting higher dipole moments was enriched in the reaction mixture.

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Note | Regular issue | Vol 45, No. 10, 1997, pp.2041-2043
Published online:
DOI: 10.3987/COM-97-7895
An Efficient Process of Ondansetron Synthesis

Moohi Yoo Kim,* Geun Jho Lim, Joong In Lim, Dong Sung Kim, Ik Yon Kim, and Jae Sung Yang

*Dong-A Pharmaceutical Co. LTd., Research Laboratories, 47-1, Sanggal-Ri, Kiheung-Up, Yongin-Si, Kyunggi-Do, 449-900, Korea

Abstract

An efficient and practical two-step synthesis of ondansetron (1) was accomplished from readily available N-methyltetrahydrocarbazolone (2) via direct Mannich α-methylenation and alumina catalyzed Michael addition resulting in a 70% overall yield.

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Note | Regular issue | Vol 45, No. 10, 1997, pp.2045-2052
Published online:
DOI: 10.3987/COM-97-7901
Three New Coumarins from Calophyllum teysmannii var. inophylloide (Guttiferae)

Shu-Geng Cao, Keng-Yeow Sim, and Swee-Hock Goh*

*Department of Chemistry, National University of Singapore, 10 Kent Ridge Crescent, 119260, Singapore

Abstract

A chemotaxonomic survey of Malaysian Calophyllum plants for potential bioactive compounds provided three new coumarins [12-methoxyinophyllum P (1), hydrohydroxyisocalanone (2) and 4-phenyl-5-methoxy-7-hydroxy-8-benzoylcoumarin (3)] from the bark of C. teysmannii var. inophylloide, together with known compounds calanone (4) and betulinic acid. Their structures were determined by spectroscopic analysis including 2D NMR.

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Note | Regular issue | Vol 45, No. 10, 1997, pp.2053-2060
Published online:
DOI: 10.3987/COM-97-7906
Studies on the Index Compounds for HPLC Analysis of Glycyrrhiza uralensis

Makio Shibano, Ayako Henmi, Yoshihiro Matsumoto, Genjiro Kusano,* Toshio Miyase, and Yoshio Hatakeyama

*Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan

Abstract

HPLC of the AcOEt extracts of subterranean (roots or stolons) samples of Glycyrrhiza uralensis showed two types of the reproducible chromatograms distinct from those of other species (G. glabra, G. pallidiflora, G. echinata, G. macedonica). As index compounds for HPLC of G. uralensis, two new compounds, named glyurallins A and B, were isolated and their structures were difined, in addition to identification of nine compounds to glycycoumarin, semilicoisoflavone B, dehydroglyasperin C, licoisoflavanone, glycyrol, glycyrin, gancaonin N, licoricidine and 8-γ,γ-dimethylallylwighteone.

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26 data found. 1 - 26 listed