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11 data found. 1 - 11 listed

Published online: 22nd May, 2015

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-15-13234
Development of a Facile and Inexpensive Route for the Preparation of α-Halobenzopyridines from α-Unsubstituted Benzopyridines

Osamu Sugimoto,* Hyuma Iwasaki, and Ken-ichi Tanji

*Laboratory of Organic Chemistry, School of Food and Nutritional Sciences, University of Shizuoka, 552-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan

Abstract

A facile and inexpensive route for the preparation of α-halobenzopyridines from α-unsubstituted benzopyridines via N-methylbenzopyridin-α-ones was developed. α-Unsubstituted benzopyridines were converted easily into the corresponding N-methylbenzopyridin-α-ones, which were halogenated using PPh3-TCICA or PPh3-DBICA without using solvent to give α-halobenzopyridines.

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Published online: 15th May, 2015

Communication | Regular issue | Prepress
DOI: 10.3987/COM-15-13227
Preparation of Acylthiophenes by Iron(III) Chloride Catalyzed Reactions of Tris(2-thienyl)stibanes with Acyl Chlorides

Naoki Kakusawa,* Yoshie Nakagawa, Yutarou Toshima, Shuji Yasuike, and Jyoji Kurita

*Faculty of Pharmaceutical Sciences, Hokuriku University, 3-Ho, Kanagawa machi, Kanazawa 920-1181, Japan

Abstract

The reactions of tris(2-thienyl)stibanes with various acyl chlorides, using a catalytic amount of iron(III) chloride, afforded 2-acylthiophenes. Iron(III) chloride is presumed to act as a Lewis acid, and the ipso substituent of each 2-thienyl group of tris(2-thienyl)stibane is replaced with an acyl group. The reaction is highly atom-efficient in that all three thiophene rings of tris(2-thienyl)stibane take part in the reaction. The reaction procedure is so simple that it can also be carried out under solvent-free and aerobic conditions.

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Published online: 14th May, 2015

Review | Regular issue | Prepress
DOI: 10.3987/REV-15-820
Chemistry of 2,5-Diketopiperazine and Its Bis-lactim Ether: A Brief Review

Shigeki Sano* and Michiyasu Nakao

*Molecular Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokushima, 1-78 Sho-machi, Tokushima 770-8505, Japan

Abstract

2,5-Diketopiperazines have attracted much attention because of their biological activities and molecular structure characteristics. Bis-lactim ethers derived from these 2,5-diketopiperazines include well-known organic molecules such as Schöllkopf chiral auxiliaries, which are used in asymmetric synthesis of α-amino acids. In this article, we briefly discuss the chemistry of both heterocyclic compounds.

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Published online: 11th May, 2015

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-15-13175
Triterpene Saponins from the Aerial Parts of Ilex Cornuta and their Cytotoxic Activity

Seung Young Lee, Won Se Suh, Ho Kyung Kim, Il Kyun Lee, Sang Un Choi, Ki Hyun Kim, and Kang Ro Lee*

*Natural Products Laboratory, School of Pharmacy, Sungkyunkwan University, 300 Chunchun-dong, Jangan-ku, Suwon 440-746, Korea

Abstract

Four new triterpene saponins (1-4), together with 13 known triterpenoids (5-17), were isolated from the MeOH extract of Ilex cornuta Lindley (Aquifoliaceae). Their structures were elucidated on the basis of chemical and spectroscopic methods. The isolated compounds were tested for their cytotoxicities against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15) in vitro using the sulforhodamine B (SRB) assay.

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Published online: 11th May, 2015

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-15-13191
An Efficient Construction of 4-oxo-4H-Chromene-2-carboxylate Derivatives via One-pot Cascade Reaction Under Solvent-free Conditions

Chao Huang,* Jia-Hui Guo, Huang-Mei Fu, Ming-Long Yuan, and Li-Juan Yang

*Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission & Ministry of Education, Engineering Research Center of Biopolymer Functional Materials, Yunnan Minzu University, 134 Yi Er Yi Avenue, Kunming, Yunnan, 650031, China

Abstract

An efficient synthetic strategy to chromone derivatives from commercially available diethyl acetylenedicarboxylate and phenols via a one-pot cascade reaction has been developed. Performing the reaction using pyridine and polyphosphoric acid as the catalyst at room temperature and 90 oC without any solvent gave the chromone derivatives in good to high yields at one time. A possible reaction pathway was also proposed and supported by the experiment. This protocol is environmentally friendly and metal-free, with advantages including short reaction times, convenient operation, and mild reaction conditions.

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Published online: 11th May, 2015

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-15-13209
Synthesis and Cytotoxicity Activity of Some Novel Hydrazide, Pyrazole, Isoxazole, Pyrimidine and Fused Pyran-2-one Derivatives

Hala M. Refat* and A. A. Fadda

*Faculty of Science, Department of Chemistry, Suez Canal University, Al-Arish, 45511, Egypt

Abstract

The reaction of 2-cyano-3-(dimethylamino)-N- ((2-methoxynaphthalen-1-yl)methylene)acrylohydrazide (2) with some nitrogen nucleophiles, phenols and compounds, having an active methylene group to synthesis polyfunctionally substituted azoles (3-5), azine (6), fused azines (7-10) and fused pyran-2-one (11-17) derivatives. All the synthesized products were confirmed by elemental analysis, IR, 1H-NMR, 13C-NMR and MS data. The antitumor evaluation of the newly products against the four human tumor cells lines namely heptacelluar carcinoma (liver) HepG-2, Colorectal carcinoma (colon) HCT-116, mammary gland (breast) MCF-7 and Epdermoid carcinoma (larynx) Hep-2 was investigated. Compound 4 exhibited superior in vitro antitumor activity in the 3-cell lines assay.

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Published online: 11th May, 2015

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-15-13213
Synthesis of 3-Ethenylindoles via Intramolecular Cyclization of Aryl Radical with Allene Generated by Samarium(II) Diiodide

Kenji Suzuki, Hiroki Iwasaki, Fumihito Ichiyoshi, Mao Tominaga, Naoto Kojima, Minoru Ozeki, and Masayuki Yamashita*

*Kyoto Pharmaceutical University, 5 Misasagi-Nakauchi, Yamashina, Kyoto, Japan

Abstract

N-(2,3-Butadien-1-yl)-N-(tert-butoxycarbonyl)-2-iodoanilines cyclized intramolecularly to form 3-ethenyl-2,3-dihydroindoles after treatment with samarium(II) diiodide. The dihydroindoles were easily oxidized to the corresponding 3-ethenylindoles in good to moderate yields.

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Published online: 27th April, 2015

Communication | Regular issue | Prepress
DOI: 10.3987/COM-15-13208
Synthesis of 1,5-Dioxaspiro[3.4]octane through Bromocation-Induced Cascade Cyclization

Atsuo Nakazaki, Yoshiki Nakane, Yuki Ishikawa, and Toshio Nishikawa*

*Laboratory of Organic Chemistry, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa, Nagoya, Aichi 464-8601, Japan

Abstract

A new approach to the synthesis of 1,5-dioxaspiro[3.4]octane, spiro-oxetane having acetal moiety, via the bromocation-induced cyclization is described. This reaction underwent to furnish spiro-oxetane in one-pot manner with a high degree of diastereoselectivity.

Supporting Info. (575KB)PDF (596KB)

Published online: 23rd April, 2015

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-15-13210
Synthesis and Anticancer Activities of Thiazoles, 1,3-Thiazines, and Thiazolidine Using Chitosan-grafted-poly(Vinylpyridine) as Basic Catalyst

Sobhi M. Gomha, Sayed M. Riyadh,* Elmahdi A. Mahmmoud, and Mahmoud M. Elaasser

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

Abstract

Three different series of ethylidenehydrazonothiazoles 5a-c, 6a-c, ethylidenehydrazono-1,3-thiazines 9a-i and ethylidenehydrazonothiazolidine 12 have been prepared via reactions of ethylidenethiosemicarbazide 3a or ethylidenethiocarbohydrazide 3b with α-halocarbonyl compounds 4a-c, acrylonitrile derivatives 7a-i, and dimethyl acetylenedicarboxylate 10, respectively. Different basic catalysts were used in these reactions such as, triethylamine, chitosan, and chitosan-grafted-poly(vinylpyridine) and the latter catalyst has precedence as environmentally friendly basic catalyst. Moreover, the selected newly synthesized products were evaluated for their anti-cancer activity against a colon carcinoma cell line (HCT-116) and liver carcinoma cell line HEPG2 and revealed promising activity especially 1,3-thiazines 9c-i.

Supporting Info. (896KB)PDF (801KB)

Published online: 21st April, 2015

Paper | Regular issue | Prepress
DOI: 10.3987/COM-15-13202
Two-Step Synthesis of 5-Hydroxy-5,7-dihydro-6H-pyrrolo[2,3-d]pyrimidin-6-one Derivatives from 4-Chloro-6-methoxy-2-(methylsulfanyl)pyrimidine

Kazuhiro Kobayashi,* Ryoga Ono, Shohei Yuba, Hidetaka Hiyoshi, and Kazuto Umezu

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

Abstract

We report a facile two-step procedure that allows the synthesis of the title fused heterocyclic derivatives from 4-chloro-6-methoxy-2- (methylsulfanyl)pyrimidine, readily available from 4,6-dichloro-2- (methylsulfanyl)pyrimidine (DCSMP). The first step is the lithiation at the 5-position of the starting material with lithium diisopropylamide (LDA) and the reaction of the resulting lithium compound with α-keto esters to give the corresponding 2-hydroxy-2-(pyrimidin-5-yl)carboxylic acid ester derivatives. In the second step, these are treated with primary aliphatic amines in the presence of triethylamine to afford the desired products.

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Published online: 10th April, 2015

Review | Regular issue | Prepress
DOI: 10.3987/REV-14-809
Recent Progress in The Synthetic Study of an Antitumor Marine Macrolide Aplyronine A and Related Molecules

Ichiro Hayakawa* and Hideo Kigoshi*

*Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki 305-8571, Japan

Abstract

Aplyronine A is a potent antitumor marine macrolide. The unique molecular structures of aplyronine A and its congeners, in conjunction with their potent biological activities, have made them attractive synthetic targets. This review discusses recent progress in the development of efficient routes to the synthesis of aplyronines and the related molecules.

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11 data found. 1 - 11 listed