Regular Issue

Vol. 53, No. 2, 2000

25 data found. 1 - 25 listed
Communication | Regular issue | Vol 53, No. 2, 2000, pp.261-264
Published online:
DOI: 10.3987/COM-99-8746
An Efficient Synthesis of New Analogs of Water-soluble and Hydrolytically Stable Deoxoartemisinin

Mankil Jung* and Jaehoon Bae

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

Abstract

Water-soluble and hydrolytically stable novel analogs of deoxoartemisinin were prepared from artemisinic acid in natural configuration.

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Communication | Regular issue | Vol 53, No. 2, 2000, pp.265-270
Published online:
DOI: 10.3987/COM-99-8760
Synthesis of New Mesomeric Betaines Containing a Triazolopyridiniumolate System and Their Unexpected Function as Masked Isocyanates

Norio Sakai, Makoto Funabashi, Satoshi Minakata, Ilhyong Ryu, and Mitsuo Komatsu*

*Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan

Abstract

A series of mesomeric betaines containing 1-alkylated triazolopyridiniumolate system were synthesized and their cycloaddition with dimethyl acetylenedicarboxylate were examined. An unusual ring-opening reaction occurred to give pyridone derivatives indicating that these betaines act as masked isocyanates.

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Communication | Regular issue | Vol 53, No. 2, 2000, pp.271-276
Published online:
DOI: 10.3987/COM-99-8778
Electron Transfer-initiated Photocyclization of Substituted α-Dehydro(1-naphthyl)alanines

Tadamitsu Sakurai,* Yoshiko Morioka, Kei Maekawa, and Kanji Kubo

*Department of Applied Chemistry, Faculty of Technology, Kanagawa University, Kanagawa-ku, Yokohama 221-8686, Japan

Abstract

On irradiation in the presence of triethylamine, the title compounds (1) having n-butyl and benzyl groups gave preferentially dihydrobenzoquinolinones (2) via electron transfer, whereas the introduction of the bulky tert-butyl and phenyl substituents into 1 resulted in the formation of benzoisoquinoline (3) and 1-azetine (4) derivatives without affording 2.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.277-290
Published online:
DOI: 10.3987/COM-99-8737
Novel Indole-fused, Medium-sized Ring Heterocycles via Chloroacetamide Photochemistry

John B. Bremner,* Henry F. Russell, Brian W. Skelton, and Allan H. White

*Department of Chemistry, University of Wollongong, Wollongong 2522 NSW, Australia

Abstract

Syntheses of derivatives of three novel indole-fused systems based on indolo[2,1-d][1,5]benzodiazocine, indolo[7,7a,1-d,e][1,6]benzodiazonine and pyrrolo[2,3-b]indolo[5,5a,6-b,a]quinazoline, the first two including 8- and 9-membered ring heterocycles, are described. These derivatives resulted from the photo-induced cyclization of the respective chloroacetamide precursors prepared via N-alkylation of the appropriate indole with 2-nitrobenzyl bromide, subsequent nitro group reduction and then N-chloroacetylation. Structural and stereochemical features of these new ring system derivatives are discussed.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.291-300
Published online:
DOI: 10.3987/COM-99-8752
Preparation of N 1-Alkyl- and N 1,N 1-Dialkylisoquinoline-1,3-diamines and 1-Alkyl- and 1-Phenylisoquinolin-3-amines from the Reaction of α-Cyano-o-tolunitrile with Lithium Amides, Alkyllithiums, and Phenyllithium

Anlai Wang, Hongming Zhang, and Edward R. Biehl*

*Chemistry Department, Southern Methodist University, Dallas, TX 75275, U.S.A.

Abstract

A facile, one-step synthesis of the titled compounds from the reaction of α-cyano-o-tolunitrile with LiNHR, LiNRR’, RLi, or PhLi is described. A mechanism is presented in which α-cyano-o-tolunitrile is first converted quantitatively to its ketenimine carbanion by the lithium base. The remaining aromatic cyano group on the ketenimine carbanion then undergoes nucleophilic attack by the lithium base to give an adduct that subsequently cyclizes to the titled compounds. The reaction of lithiated anilines, nitriles, methanol, and pryrrole failed, presumably due to their inability to deprotonate α-cyano-o-tolunitrile.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.301-314
Published online:
DOI: 10.3987/COM-99-8754
Olefin Metathesis Reactions of Some Aromatic Dienes with ortho- and meta- Disubstitution. Formation of 10-, 12-, 14-, and 17-Membered Cyclic Compounds and Isomerization of an Allylic Alcohol

Katsuyuki Nakashima, Rika Ito, Masakazu Sono, and Motoo Tori*

*Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima, 770-8514, Japan

Abstract

Some aromatic dienes with ortho- and meta-disubstitution have been subjected to olefin metathesis reactions. Compounds having allylphenyl groups substituted at their ortho positions successfully cyclized into 12-, 14-, and 17-membered alkenes in moderate to good yields, while compounds having the same groups substituted at their meta positions and those having vinylphenyl groups substituted at their ortho positions afforded mainly polymers. o-Allylphenyl 5-hexenyl ether produced 10-membered cyclooxadecadiene in 7.5% yield.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.315-322
Published online:
DOI: 10.3987/COM-99-8765
Regioselective Synthesis of 1,5-Diazaanthraquinones via Diels-Alder Reaction of 4-Hydroxyquinolinequinone with 1-Aza-1,3-butadiene

Yoshie Horiguchi, Akio Toeda, Katsuhiro Tomoda, and Takehiro Sano*

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

Abstract

Diels-Alder (D-A) reaction of 4-methoxy-2-phenylquinoline- 5,8-dione (3a) and 4-hydroxy-2-phenylquinoline-5,8-dione (3c) with 3-methyl-1-dimethylamino-1-aza-1,3-butadiene proceeded in a regioselective manner to give 4-methoxy-7-methyl-2-phenylpyrido[3,2-g]quinoline-5,10-dione (1,8-diazaanthraquinone) (7) and 4-hydroxy-8-methyl-2-phenylpyrido[2,3-g]quinoline-5,10-dione (1,5-diazaanthra-qinone) (10), respectively, after the C ring aromatization. The inverse regioselectivity observed in the case of 3c is related to the presence of the hydrogen bonding between 4-OH and 5-CO group. This result demonstrated that D-A reaction of the azadienophiles with 1-azadiene provides a method for synthesizing 1,8-diaza- and 1,5-diazaanthraquinone, respectively.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.323-330
Published online:
DOI: 10.3987/COM-99-8769
Synthesis and Some Reactions of 1,8-Diamino-1-azaazulenium Salts

Noritaka Abe,* Kunihiko Odagiri, Hiroyuki Fujii, and Akikazu Kakehi

*Department of Chemistry, Faculty of Science, Yamaguchi University, Yamaguchi 753-8512, Japan

Abstract

Amination of 8-amino-3-phenyl-1-azaazulene gave 1,8-diamino-3-phenyl-1-azaazulenium salt (2). Reactions of the salt (2) with triethyl orthoformate and acetic anhydride gave 1-phenyl-2a,3,5-triazabenz[cd]azulene derivatives (3a and 3b). The compound (3a) was also obtained by the reaction of 2 with diethyl ethoxymethylenemalonate in the presence of potassium carbonate. The reaction of 2 with ethyl pyruvate gave 4-acetyl-1-phenyl-2a,3,5-triazabenz[cd]azulene (3c). The structure of 3c was deduced by X-Ray structure analysis. Reaction of 2 with acetylenic esters in the presence of potassium carbonate gave 2a,3-diazabenz[cd]azulene derivatives (10a, b).

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.331-337
Published online:
DOI: 10.3987/COM-99-8772
A Convenient Route to β-Phenylthioalkyl Ketones

Alan R. Katritzky,* Yunfeng Fang, Daming Feng, Alina Silina, and Indra Prakash

*Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611-7200, U.S.A.

Abstract

The preparation of β-phenylthioalkyl ketones via the reactions of α-benzotriazolylalkyl phenyl sulfides (1a-e) with enamines (5a-d) is described.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.339-346
Published online:
DOI: 10.3987/COM-99-8775
Transformations of (S )-1-Acyl-3-[(E )-(dimethylamino)methylidene]-5-(methoxycarbonyl)pyrrolidin-2-ones. A One-Step Synthesis of (S)-N -Benzoyl-3-(1-heteroaryl-5-hydroxy-1H -pyrazolyl-4)alanine Esters

Marko Skof, Jurij Svete,* and Branko Stanovnik*

*Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, 1000 Ljubljana, Slovenia

Abstract

(S)-1-Benzoyl-3-[(E)-(dimethylamino)methylidene]-5-(methoxycarbonyl)pyrrolidin-2-one (1) and (S)-1-tert-butoxycarbonyl-3-[(E)-(dimethylamino)methylidene]-5-(methoxy-carbonyl)pyrrolidin-2-one (2) were transformed in one step with various hydrazines (3-10) into the corresponding (S)-3-(1-substituted 5-hydroxy-1H-pyrazolyl-4)alanine methyl esters (11-19).

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.347-351
Published online:
DOI: 10.3987/COM-99-8780
A Novel Ring Closure Reaction for the Preparation of 6-Aminouracils with an α-Branched 1-Substituent

Friederike Fülle and Christa E. Müller*

*Pharmazeutishes Institut, Pharmazeutische Chemie Poppelsdorf, Universität Bonn, Kreuzbergweg 26, D-53115 Bonn, Germany

Abstract

The preparation of 6-aminouracil derivatives is described involving a novel, silicon-promoted ring closure reaction. Condensation of N-substituted urea with cyanoacetic acid yields cyanoacetylureas, which are heated in hexamethyldisilazane/trimethylchlorosilane to afford N-substituted 6-aminouracils. Previously unaccessible derivatives bearing an α-branched 1-substituent, including 6-amino-1-(1-phenylethyl)uracil were obtained.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.353-357
Published online:
DOI: 10.3987/COM-99-8781
Reaction of 2-Hydrazino-1-azaazulene with Diphenylnitrone: Unexpected Formation of Phenylimino-p-benzoquinone-N -oxide

Noritaka Abe,* Haruhiko Matsuda, Hiroyuki Fujii, and Akikazu Kakehi

*Department of Chemistry, Faculty of Science, Yamaguchi University, Yamaguchi 753-8512, Japan

Abstract

Reaction of 2-hydrazino-1-azaazulene with diphenylnitrone gave benzaldehyde (1-azaazulen-2-yl)hydrazone (2) and phenylimino-p-benzoquinone-N-oxide (3). Reaction mechanism for the formation of 2 and 3 was discussed.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.359-372
Published online:
DOI: 10.3987/COM-99-8786
New Reduction Reaction of Benzylic Alcohols with Acid and Proof of the Intermolecular Hydride Shift Mechanism

Masaru Kihara,* Jun-ichi Andoh, and Chiaki Yoshida

*Graduate of School of Pharmaceutical Sciences, University of Tokushima, Sho-machi, Tokushima 770-8505, Japan

Abstract

The new reduction reaction of the hydroxy groups of 4-hydroxy-4-phenyl-1,2,3,4-tetrahydroisoquinolines (1) to the corresponding alkanes (2) with mineral and Lewis acids is reported. A stereoselective intermolecular hydride shift mechanism of the reduction was proved by reaction of the deuterated derivateives (14 and 15) of 1a with 10N HCl-C2H5OH and BBr3 in CH3CN.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.373-380
Published online:
DOI: 10.3987/COM-99-8787
Investigation on the Reaction of 2-Chloro-10H -phenothiazine under Aryne Forming Conditions

Anlai Wang, Hongming Zhang, and Edward R. Biehl*

*Chemistry Department, Southern Methodist University, Dallas, Texas 75275, U.S.A.

Abstract

The reaction of 2-chloro-10H -phenothiazine with a variety of arylacetonitriles and α-cyano-o-tolunitrile in the presence of LTMP gave 2-arylmethyl-10H -phenothiathiazine-1-carbonitriles and 13-amino-14H -naphtho[2,3-b]phenothiazine-8-carbonitrile, respectively. Interestingly, LTMP effectively trapped 10-lithio-1,2-didehydrophenothiazine to give 2-(2,2,6,6-tetramethylpiperidin-1-yl)-10H -phenothiazine.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.381-386
Published online:
DOI: 10.3987/COM-99-8790
Catalytic Asymmetric Synthesis of Chiral 4-Pyrazolylalkanols by the Enantioselective Alkylation of Pyrazole-4-carbaldehydes with Dialkylzincs

Shigehisa Tanji, Harumi Aoyagi, Hayami Tabira, Itaru Sato, and Kenso Soai*

*Department of Applied Chemistry, Faculty of Science, Science University of Tokyo, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan

Abstract

(1S,2R)-N,N-Dialkylnorephedrines catalyze the enantioselective alkylation of various pyrazole-4-carbaldehydes with dialkylzincs. Enantiomerically enriched secondary-4-pyrazolylalkanols with up to 95% e.e. were obtained.

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Paper | Regular issue | Vol 53, No. 2, 2000, pp.387-395
Published online:
DOI: 10.3987/COM-99-8794
Synthesis of New Thiazolo[5,4-a]acridine Derivatives

Maxime Robin, Robert Faure, Alain Périchaud, and Jean-Pierre Galy*

*Laboratoire de Valorisation de le Chimie Fine, Faculté des Sciences et Techniques de Saint Jérôme, Université d’Aix-Marseille III, Avenue Escardille Normandie Niemen, 13397 Marseille Cedex 20, France

Abstract

Three 2-substituted thiazolo[5,4-a]acridin-11(6H)-ones and seven 11-thioxo-, 11-alkylimino-, and 11-phenoxythiazolo[5,4-a]acridines have been prepared. All these new acridines obtained in good yields have an angularly fused ring system, which has been determined by 1H- and 13C-NMR spectral data.

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Note | Regular issue | Vol 53, No. 2, 2000, pp.397-407
Published online:
DOI: 10.3987/COM-99-8724
Synthesis of Bridged Head Methyl 3,4-O-(1’,2’-Dimethylcycloheaxane-1’,2’-diyl)-6,7-dideoxy-α-D-mannooct-6-enepyranose-8,2-lactone from D-Mannose

Hammed H. A. M. Hassan*

*Chemistry Department, Faculty of Science, Alexandria University, P.O.426-Ibrahimia, 21321 Alexandria, Egypt

Abstract

The vicinal diequatorial diol at C-3 and C-4 of (1) was masked as cyclohexane diacetal derivative (2). Selective protection of C-2 as benzyl ether (3a) and Swern oxidation of the primary 6-OH gave the aldehyde derivative (4). Stereoselective Wittig condensation of 4 with Ph3P=CH-CO2Me followed by debenzylation and cyclization afforded the bridged α,β-unsaturated lactone derivative (8) in a moderate overall yield.

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Note | Regular issue | Vol 53, No. 2, 2000, pp.409-417
Published online:
DOI: 10.3987/COM-99-8753
Synthesis of Pyridopyranoquinolines by the Skraup Reaction of Amino-5H-benzopyrano[2,3-b]pyridin-5-ones

Hidetoshi Fujiwara* and Kouki Kitagawa

*Niigata College of Pharmacy, 5-13-2 Kamishin’ei-cho, Niigata 950-2081, Japan

Abstract

7-, 8- and 9-amino-5H-[1]benzopyrano[2,3-b]pyridin-5-ones were synthesized. Skraup reaction of 6-amino-, 7-amino-, 8-amino- and 9-amino-5H-[1]benzopyrano[2,3-b]pyridin-5-ones in the presence of glycerol, fuming sulfuric acid, nitrobenzene, iron(II) sulfate and boric acid gave 12H-pyrido[3’,2’:5,6]pyrano[2,3-h]quinolin-12-one, 12H-pyrido[3’,2’:5,6]pyrano[3,2-f]quinolin-12-one, 7H-pyrido[3’,2’:5,6]pyrano[2,3-f]quinolin-7-one and 7H-pyrido[3’,2’:5,6]pyrano[3,2-h]quinolin-7-one, respectively.

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Note | Regular issue | Vol 53, No. 2, 2000, pp.419-422
Published online:
DOI: 10.3987/COM-99-8755
Exchange Aminations in Conversions of Pyrimidinium Iodides to 2-Alkylaminonicotinic Acids

Gevorg G. Danagulyan,* Larisa G. Sahakyan, Alan R. Katritzky,* and Sergey N. Denisenko

*Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611-7200, U.S.A.

Abstract

1-Alkyl-2-(ethoxycarbonylmethyl)pyrimidinium iodides (1) are transformed into 2-alkylaminonicotinic acids (2) by reactions with aliphatic primary amines. Two alternative reaction paths are proposed, one of which involves exchange of the amine moieties.

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Note | Regular issue | Vol 53, No. 2, 2000, pp.423-432
Published online:
DOI: 10.3987/COM-99-8766
Synthesis of Two Novel Tricyclic Rings: Triazolo[4,5-g]quinolines and Pyrido[2,3-g]quinoxalines Derived from 6,7-Diaminoquinolines

Paolo Sanna,* Antonio Carta, and Giuseppe Paglietti

*Dipartimento Farmaco-Chimico-Tossicologico - University of Sassari, Via Muroni 23/a - 07100 Sassari, Italy

Abstract

A general simple route for the synthesis of triazolo[4,5-g]quinolines and pyrido[2,3-g]quinoxalines is described. The heterocycles obtained were fully characterised by their spectroscopical properties. A revision of the nitration of the 2,3-dichloroacetanilide is also discussed, since it afforded the request nitro derivative to build up the key intermediate 6,7-diaminoquinolines.

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Note | Regular issue | Vol 53, No. 2, 2000, pp.433-439
Published online:
DOI: 10.3987/COM-99-8774
Reactions of 1,2-Dimethyl-3-arylsulfonyl-4,5-dihydro-3H-imidazol-1-ium Iodides with Bifunctional Nucleophiles

Peiwen Zhou,* Bingjun Zhao, Jianxin Chen, Hongxing Wang, Congmin Kang, and Chizhong Xia

*Prolinx, Inc. 22322 20th Avenue, SE, Bothell, WA 98021, U.S.A.

Abstract

The reaction of imidazolium salts, represented by 1,2-dimethyl-3-arylsulfonyl-4,5-dihydro-3H-imidazol-1-ium iodides (16), with two types of bifunctional nucleophiles: ortho-substituted anilines and ethylenediamine was studied. Their reactions with 1,2-phenylenediamine, 2-aminophenol, and 2-aminothiophenol resulted in exclusively one-carbon unit transfer products: 2-methylbenzoxazole (7), 2-methylbenzimidazole (8), and 2-methylbenzothiazole (9) respectively, which mimics the one-carbon unit transfer reaction of N (5), N (10)-methenyltetrahydrofolate coenzyme. The reaction of imidazolium (3, 4, and 6) with ethylenediamine exclusively produced the bis-adducts of two equivalents of imidazolium iodides with one equivalent of ethylenediamine: N-methyl-N-(2-arylsulfonylamino)ethyl -N’-[2-(N’-2-arylsulfonylaminoethyl -N’-methyl)ethylideneamino]ethylacetamidine bishydroiodides (1012) respectively. These different behaviors were explained with addition reaction mechanism.

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Note | Regular issue | Vol 53, No. 2, 2000, pp.441-446
Published online:
DOI: 10.3987/COM-99-8782
A Novel Dimeric Coumarin from Citrus lumia

Yukiko Iwase, Maki Takahashi, Tamayo Tada, YukoTakemura, Motoharu Ju-ichi,* Chihiro Ito, Hiroshi Furukawa, Toshihiro Hashimoto, Shigeru Takaoka, Yoshinori Asakawa, and Masamichi Yano

*Faculty of Pharmaceutical Sciences, Mukogawa-Women’s University, Nishinomiya, Hyogo 663-8179, Japan

Abstract

A new dimeric coumarin, bergapten dimer (2), was isolated from the peel of Citrus lumia RISSO in addition to the known nine coumarins, one triterpene, one steroid, and two unidentified flavones. The structure of the dimer was elucidated by X-Ray crystallographic analysis.

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Note | Regular issue | Vol 53, No. 2, 2000, pp.447-452
Published online:
DOI: 10.3987/COM-99-8791
Improved Synthesis of an Energetic Material, 1,3,3-Trinitroazetidine Exploiting 1-Azabicyclo[1.1.0]butane

Kazuhiiko Hayashi, Toshio Kumagai, and Yoshimitsu Nagao*

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

Abstract

Expeditious synthesis of 1-nitroso-3-nitroazetidine (6), a useful key intermediate for the synthesis of 1,3,3-trinitroazetidine (4), was investigated by using 1-azabicyclo[1.1.0]butane (3) and NaNO2 in the presence of some acids. The most efficient method was achieved in 26% yield by treatment of 3 with NaNO2 in the presence of H2SO4. Conversion of 6 into 4 was also carried out.

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Review | Regular issue | Vol 53, No. 2, 2000, pp.453-474
Published online:
DOI: 10.3987/REV-99-526
Anti HIV-1 Active Calophyllum Coumarins: Distribution, Chemistry, and Activity

Tsutomu Ishikawa*

*Faculty of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan

Abstract

Some dipyranocoumarins isolated from Calophyllum genus, Guttiferae (Clusiaceae), show anti HIV-1 activity. The HIV-1 active Calophyllum coumarins such as (+)-calanolide A [(+)-1] and (+)-inophyllum B [(+)-13] have a (2R,3S,4S)-2,3-dimethyl-4-chromanol ring as common structural requirements, whereas closely related coumarins were significantly less active or totally inactive. Thus, the stereochemistry of the chromanol ring in Calophyllum coumarins could be responsible for anti HIV-1 activity. Calanolide A [(+)-1] has currently been included in clinical trials. This review describes the distribution, chemistry, and the anti HIV-1 activity of Calophyllum coumarins.

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Review | Regular issue | Vol 53, No. 2, 2000, pp.475-488
Published online:
DOI: 10.3987/REV-99-525
Ring Closure Reactions of Suitably ortho-Substituted Maleanilic Acids: An Avenue for Heterocycles

Narshinha P. Argade* and Vaidhyanatha Balasubramaniyan

*Division of Organic Chemistry (Synthesis), National Chemical Laboratory, Pune 411 008, India

Abstract

This review describes syntheses of structurally interesting and biologically important heterocycles starting from suitably ortho-substituted maleanilic acids via intramolecular Michael addition, condensation and dehydrative cyclisation reactions.

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25 data found. 1 - 25 listed