Regular Issue

Vol. 75, No. 12, 2008

19 data found. 1 - 19 listed
Review | Regular issue | Vol 75, No. 12, 2008, pp. 2893 - 2929
Published online: 24th July, 2008
DOI: 10.3987/REV-08-634
Reaction of Hydrazines and Hydroxylamine with Trifluoromethyl-β-diketones: Synthesis of Trifluoromethylpyrazole and Isoxazole Derivatives

Vinod Kumar, Ranjana Aggarwal, and Shiv P. Singh*

*Department of Chemistry, Kurukshetra University, Kurukshetra -136 119, India


The reaction of trifluoromethyl-β-diketones with hydrazines and hydroxylamine finds interesting application in the synthesis of trifluoromethylpyrazole and isoxazole derivatives. The review covers the literature of the reactions mentioned up to 2007. Mechanistic aspects leading to the formation of these heterocycles and their NMR spectral characteristics are also described.

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Communication | Regular issue | Vol 75, No. 12, 2008, pp. 2931 - 2936
Published online: 11th August, 2008
DOI: 10.3987/COM-08-11483
Rhodium-catalyzed Arylation of 2-Azabicyclo[2.2.1]hept- 5-en-3-one with Arylboronic Acids under Microwave Irradiation

Takumi Abe, Hiroyuki Takeda, Yumi Takahashi, Yoshihisa Miwa, Koji Yamada, and Minoru Ishikura*

*Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido 061-0293, Japan


Rhodium-catalyzed arylation of 2-azabicyclo[2.2.1]hept-5-en-3-one was successfully performed by applying microwave irradiation.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 2937 - 2948
Published online: 10th July, 2008
DOI: 10.3987/COM-08-11426
Synthesis and Antimicrobial Evaluation of Some Bis(thioxopyridine), Bis(pyrazolo[3,4-b]pyridine), Bis(thieno[2,3-b]pyridine), Bis(1,3,4-Thiadiazole) and Bisthiophene Derivatives

Nabila A. Kheder, Yahia N. Mabkhot, and Ahmad M. Farag*

*Department of Chemistry, Faculty of Science, Cairo University, Giza 12613, Egypt


Condensation of the N,N’-(ethane-1,2-diyl)bis(cyanoacetamide) (1) with aromatic aldehydes gave the corresponding N,N’-ethane-1,2-diyl)- bis(2-cyano- 3-phenylacrylamide) derivatives 2a-c. The latter products react with 2-cyanothioacetamide to afford 1,2-bis(4-aryl-3,5-dicyano-6-mercapto-2-oxo-1,2- dihydropyridin-1-yl)ethane derivatives 5a-c. Treatment of 1,2-bis(3,5-dicyano- 6-mercapto-2-oxo-4-phenyl-1,2-dihydropyridin-1-yl)ethane (5a) or its S-methyl derivative 6 with hydrazine hydrate afforded 1,2-bis(3-amino-5-cyano-6,7- dihydro-7-methyl-6-oxo-4-phenyl-1H-pyrazolo[3,4-b]pyridin-1-yl)ethane (7). Reaction of bis(6-mercaptopyridine) 5b with chloroacetone gave the 1,2- bis[2-acetyl-3-amino-6,7-dihydro-5-cyano-4-(4-methoxyphenyl)-6-oxothieno[2,3-b]pyridine-7-yl]ethane (9). Treatment of the bis(cyanoacetamide) 1 with phenyl isothiocyanate afforded N,N’-(ethane-1,2-diyl)bis[2-cyano-3-mercapto-3-(phenyl amino)acrylamide] (11) which reacts with hydrazonoyl halides 12a,b or haloketones 15a-c to give the corresponding N,N’-(ethane-1,2-diyl)bis[2-cyano- 2-(3,5-disubstituted-2(3H)-1,3,4-thiadiazolylidene)acetamides] 14a,b or N,N’-(ethane-1,2-diyl)bis[4-amino-5-substituted-2-(phenylamino)thiophene-3-carboxamide] 16a-c derivatives, respectively. Antimicrobial evaluation of selected example of the newly synthesized compounds was carried out.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 2949 - 2958
Published online: 10th July, 2008
DOI: 10.3987/COM-08-11443
A New Approach to the Benzopyridoxepine Core by Metal Mediated Intramolecular Biaryl Ether Formation

Georgeta Serban,* Hitoshi Abe, Yasuo Takeuchi, and Takashi Harayama*

*Faculty of Medicine and Pharmacy, Oradea University, Oradea 410028, Romania


This paper presents a concise synthesis of the novel [1,3]dioxo[d]benzoxepino[2,3-c]-6-bromopyridine 1. The benzopyridoxepine core has been obtained by intramolecular coupling of a benzopyridylethene that is in turn obtained from the Wittig reaction. Thus, the synthesis was accomplished in a very good yield by implementation of an intramolecular palladium-catalyzed biaryl ether formation (Buchwald-Hartwig type reaction). An alternative approach based on the copper-mediated C-O bond formation (intramolecular Ullmann reaction) was not successful.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 2959 - 2971
Published online: 17th July, 2008
DOI: 10.3987/COM-08-11457
Efficient Formation of a Triazole Ring via Novel Ring-opening Reaction of (Z)-2-Methyl-4-arylmethylene-5(4H)-oxazolones with Hydrazides

Kei Maekawa, Atsushi Tomoda, Tetsutaro Igarashi, and Tadamitsu Sakurai*

*Department of Material and Life Chemistry, Faculty of Engineering, Kanagawa University, Kanagawa-ku, Yokohama 221-8686, Japan


The ring-opening mode of the title oxazolones with hydrazide nucleophiles was investigated from both synthetic and mechanistic points of view. It was found that the novel ring-opening reaction proceeded to give (Z)-2-(3-methyl-5-substituted 1,2,4-triazol-4-yl)-3-aryl-2-propenoic acids [1,2,4-triazole-substituted (Z)-α-dehydroarylalanines] as major products, along with minor or negligible amounts of their isomers. Substituent and solvent effects on the relative composition of these two isomers confirmed that this composition was dependent on steric and electronic factors of the aryl (in the oxazolones) and acyl (in the hydrazide nucleophiles) substituents as well as on solvent polarity. MM2 and PM5 calculations provided a strong piece of evidence in support of the mechanism in which the triazole ring is constructed via the preferential nucleophilic addition of the hydrazino nitrogen to the C=N double bond in the oxazolone ring.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 2973 - 2980
Published online: 17th July, 2008
DOI: 10.3987/COM-08-11458
A Simple and Practical Synthesis of Methyl Benzo[b]furan-3-carboxylates

Ferdinand S. Melkonyan, Nikita E. Golantsov, and Alexander V. Karchava*

*Department of Chemistry, M. V. Lomonosov Moscow State University, Moscow 119992, Russia


A simple and practical two-step procedure for the preparation of 2-unsubstituted 1-benzo[b]furan-3-carboxylic acid methyl esters is described. The procedure uses the copper-catalyzed intramolecular C-O bond formation and provides an efficient route to the title compounds in good to excellent yields.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 2981 - 2988
Published online: 17th July, 2008
DOI: 10.3987/COM-08-11463
Rearrangement of Dialkyl-2-(azetidin-3-yl)propane-1,3-dioates - A Structural Revision

Mark R. Faust, Cornelia E. Hoesl, and Klaus T. Wanner*

*Department of Pharmacy - Center for Drug Research, LMU Munich, Butenandtstr. 5-13, D-81377 Munich, Germany


The rearrangement reaction of dialkyl 2-[1-diphenylmethyl)azetidin-3-yl]propane-1,3-dioates during saponification was studied. Contrary to a previous report postulating the formation of a 4-(hydroxy-methyl)-2-oxo-pyrrolidine-3-carboxylic acid derivative, our analytical data showed that the rearrangement reaction led to a lactone ring. This structural revision is based on elemental analysis, IR and two-dimensional NMR studies.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 2989 - 3004
Published online: 10th July, 2008
DOI: 10.3987/COM-08-11464
Facile Synthesis of Model Indazolo[2,1-c][1,3,4]benzotriazepin-5,13-diones

Jalal A. Zahra, Mustafa M. El-Abadelah,* Bassam A. Abu Thaher, Stefan Laufer, and Roland Boes

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


In basic media, 2-aminobenzoic acids (5) react with 2-[N-(1-carboxyphenyl)]hydrazonoyl chlorides (6, 7) (precursors of the reactive nitrile imine 1,3-dipolar species) to afford good yields of the corresponding 2-[N’-(1-carboxyphenyl-2-amino)hydrazino]benzoic acids (8a-d, 9a). The latter acyclic adducts, in the presence of 1,1‘-carbonyldiimidazole (CDI), undergo two consecutive lactamizations involving both activated carboxyl groups and the suitably located hydrazino-NH partners, to deliver the respective indazolo[2,1-c]- [1,3,4]benzotriazepin- 5,13-diones (10a-d, 11a). Structural assignments for these novel tetracyclic products are based on analytical and spectral (IR, MS, NMR) data, and confirmed by single crystal X-ray structure determination for 10a.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 3005 - 3014
Published online: 4th August, 2008
DOI: 10.3987/COM-08-11471
Synthesis and Antimicrobial Evaluation of Novel Pyrazolo[1,5-a]pyrimidine, Pyrimido[1,2-a]benzimidazole, Triazolo[4,3-a]pyrimidine and Pyrido[1,2-a]benzimidazole Derivatives Incorporated Phenylsulfonyl Moiety

Mohamed R. Shaaban*

*Department of Chemistry, Faculty of Science, Cairo University, Giza 12613, Egypt


Phenylsulfonylacetonitrile (1) reacts with dimethylformamide dimethyl acetal (DMF-DMA) to afford 3-(dimethylamino)-2-(phenylsulfonyl)acrylonitrile (2). Enaminonitrile 2 reacts with 5-aminopyrazole derivatives 3a-e, 2-amino-1,2,4-triazole (7) and 2-aminobenzimidazole (11) to afford new pyrazolo[1,5-a]pyrimidine, triazolo[4,3-a]pyrimidine and pyrimido[1,2-a]benzimidazole derivatives 4a-e, 9 and 12, respectively. Also, 3-(dimethylamino)-2-(phenylsulfonyl)acrylonitrile (2) reacts with 2-(1H-benzimidazol-2-yl)acetonitrile (13) to give the corresponding pyrido[1,2-a]benzimidazole derivative 15. Some of the newly synthesized compounds were tested in vitro for their antibacterial and antifungal activities, and showed promising results.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 3015 - 3024
Published online: 28th July, 2008
DOI: 10.3987/COM-08-11472
Novel and Efficient Access to Thieno[3,4-c]cinnolines

Karine Gehanne, Jean-Charles Lancelot, Stéphane Lemaître, Hussein El-Kashef, and Sylvain Rault*

*Centre d’Etudes et de Recherche sur le Médicament de Normandie UPRES EA 4258 PR CNRS INC3M - Université de Caen Basse-Normandie, U.F.R. des Sciences Pharmaceutiques, 5, rue Vaubénard - 14032 Caen, France


New substituted methyl thieno[3,4-c]cinnoline-3-carboxylate compounds were synthesized from the corresponding methyl 3-aminothiophene-2-carboxylate precursors by a new route using a modified Sandmeyer reaction. Under proper conditions, Sandmeyer reaction led to the formation of thieno[3,4-c] cinnoline compounds by a regioselective intramolecular cyclization, instead of the expected substitution of the amino group by a bromine atom.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 3025 - 3033
Published online: 31st July, 2008
DOI: 10.3987/COM-08-11473
Synthesis of 1-Iminoisothiochroman Derivatives Based on Reactions of 2-Lithio-β-methoxystyrene Derivatives with Isothiocyanates Followed by Acid-mediated Cyclization

Kazuhiro Kobayashi,* Daisuke Nakai, Kazutaka Hayashi, and Hisatoshi Konishi

*Division of Applied Chemistry, Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Koyama-minami, Tottori 680-8552, Japan


The reaction of 2-lithio-β-methoxystyrene derivatives with isothiocyanates yields the corresponding 2-(2-methoxyvinyl)thiobenzamide derivatives. Treatment of these thiobenzamides with concentrated hydriodic acid affords 1-imino-3-methoxyisothiochroman (1-imino-3-methoxy-3,4-dihydro-1H- 2-benzothiopyran) derivatives.

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Paper | Regular issue | Vol 75, No. 12, 2008, pp. 3035 - 3042
Published online: 18th August, 2008
DOI: 10.3987/COM-08-11479
Furanoeremophilanes and Other Constituents of Pittocaulon bombycophole

Jhon Ironzi Maldonado R., Amira Arciniegas, Ana-L. Pérez Castorena, José Luis Villaseñor, and Alfonso Romo de Vivar*

*Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, CoyoacÁn 04510, D.F. México


Three new eremophilanes (1-3) and a new oplopane (4) were isolated from Pittocaulon bombycophole. Additionally, three known sesquiterpenes (5-7) and the alkaloid 7-angeloylplatynecine (8) were isolated. The structures of the new compounds were elucidated by spectroscopic methods.

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Note | Regular issue | Vol 75, No. 12, 2008, pp. 3043 - 3049
Published online: 22nd July, 2008
DOI: 10.3987/COM-08-11413
Grayanane Diterpenoids from the Barks of Craibiodendron henryi

Xiang-zhong Huang,* Rong Huang, Gang Du, Yan Yin, Yun Dai, and Ming-qian Yu

*School of Chemistry and Biotechnology, Yunnan Nationalities University, Kunming 650031, People’s Republic of China


Three new grayanane diterpenoids, 14β-O-(2S,3R-nilyl)rhodomollein XVIII (1), 14β-O-(2S,3R-nilyl)rhodomollein I (2) and 14β-O-(2S,3R-nilyl) rhodojaponin III (3) have been isolated from the barks of Craibiodendron henryi. Their structures were determined on the basis of chemical and spectral methods. Vasodilator effects of these compounds were assessed.

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Note | Regular issue | Vol 75, No. 12, 2008, pp. 3051 - 3056
Published online: 10th July, 2008
DOI: 10.3987/COM-08-11438
Singaporentine A: A New Indole Alkaloid from Kopsia singapurensis Ridl.

Khalijah Awang,* Kartini Ahmad, Noel F. Thomas, Yusuke Hirasawa, Koichi Takeya, Mat Ropi Mukhtar, Khalit Mohamad, and Hiroshi Morita

*Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia


Study on chemical constituents from the leaves of Kopsia singapurensis (Apocynaceae) yielded a new indole alkaloid, singaporentine A (1) together with two known alkaloids, kopsifoline A (2) and kopsininic acid (3). The structure of 1 was elucidated by combination of various spectroscopic methods such as MS, UV, IR, 1D and 2D NMR. Singaporentine A exhibited cytotoxic activity against P388 murine leukemia cells.

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Note | Regular issue | Vol 75, No. 12, 2008, pp. 3057 - 3064
Published online: 4th August, 2008
DOI: 10.3987/COM-08-11440
Coumarins and Flavones from Casimiroa pringlei

Emma Maldonado, Imelda Márquez, Fernando Chiang, and Alfredo Ortega*

*Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Coyoacán, 04510, D. F., México


A chemical study of the leaves of Casimiroa pringlei led to the isolation of six coumarins, six flavones and the sesquiterpene, cryptomeridiol. Four of these compounds are new natural products which, on the basis of spectroscopic analyses, were characterized as (Z)-trichoclin acetate, 5,3’,5’-trimethoxyflavone, 5,2’,3’,4’-tetramethoxyflavone, and 5,2’,3’,4’,5’,6’-hexamethoxyflavone. Although 5,2’,3’,4’-tetramethoxyflavone has been obtained by synthesis, this is the first report of its isolation from a natural source.

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Note | Regular issue | Vol 75, No. 12, 2008, pp. 3065 - 3075
Published online: 10th July, 2008
DOI: 10.3987/COM-08-11455
An Alternative Preparation of Pyrazolo-pyridine Derivatives in Ionic Liquid and Comparison Study on the Reactivity of Thioamide and Amide Group

Xin-Ying Zhang, Xiao-Yan Li, Xue-Sen Fan,* Xia Wang, Gui-Rong Qu,* and Jian-Ji Wang

*School of Chemical and Environmental Sciences, Henan Key Laboratory for Environmental Pollution Control, Henan Normal University, Xinxiang, Henan 453007, P. R. China


A novel and efficient preparation of pyrazolo[3,4-b]pyridine (5) and pyrazolo[3,4-b]pyridin-6-one (8) derivatives from the condensation of arylidenecyanothioacetamide (1) or arylidenecyanoacetamide (7) with 5-amino- 3-methyl-1-phenylpyrazole (4) in [bmim]BF4 is reported for the first time. The mechanism for the formation of 5 from 1 and 4, or 8 from 7 and 4, and the comparison between the reactivity of thioamide group versus amide group are briefly discussed.

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Note | Regular issue | Vol 75, No. 12, 2008, pp. 3077 - 3083
Published online: 18th August, 2008
DOI: 10.3987/COM-08-11459
Efficient Synthesis of 1,8-Dioxo-octahydroxanthenes Using HClO4/SiO2 as Catalyst

Gholam Hossein Mahdavinia, Mohammad A. Bigdeli,* Yaser Saeidi Hayeniaz, and Firouzeh Nemati

*Faculty of Chemistry, Tarbiat Moalem University, 49 Mofateh St., Tehran, Iran


Silica supported perchloric acid (HClO4/SiO2) is found to be a heterogeneous recyclable catalyst for rapid and efficient synthesis of 1,8-dioxo-octahydroxanthenes with good to excellent yields in solvent free conditions. The catalyst is easily prepared, stable, reusable and efficiently used under reaction condition.

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Note | Regular issue | Vol 75, No. 12, 2008, pp. 3085 - 3089
Published online: 17th July, 2008
DOI: 10.3987/COM-08-11462
Studies of the Egyptian Traditional Folk Medicines. IV. New Isoflavonoid Isolated from Egyptian Licorice

Masaki Baba,* Sakiko Sumi, Noriaki Iwasaki, Hisahiro Kai, Masami Sakano (nee Komiya), Yoshihito Okada, and Toru Okuyama

*Natural Medicine and Phytochemistry, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588 Japan


A new isoflavonoid, 2′,4′-dihydroxy[6″,6″-dimethylpyrano (2″,3″:7,8)]isoflavone, named isoglabrone, was isolated from the ethyl acetate extract of Egyptian licorice, Glycyrrhiza glabra, together with 10 known phenolic compounds. The structure was elucidated on the basis of spectrometric evidence.

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Note | Regular issue | Vol 75, No. 12, 2008, pp. 3091 - 3097
Published online: 17th July, 2008
DOI: 10.3987/COM-08-11465
A Mild and Efficient Synthesis of New 3-Phenylthienotriazolopyrimidine Derivatives Using Iodobenzene Diacetate

Byeoung Sun Joe, Hoon Young Son, and Yang-Heon Song*

*Department of Chemistry, Mokwon University, Daejeon 302-729, Republic of Korea


New 3-phenylthieno[3,2-e][1,2,4]triazolo[4,3-c]pyrimidine 9a-i and 3-phenylthieno[2,3-e][1,2,4]triazolo[4,3-c]pyrimidine 10a-i derivatives were easily synthesized at rt in high yield by the oxidative cyclization of thienopyrimidinyl hydrazones using iodobenzene diacetate.

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19 data found. 1 - 19 listed