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Published online: 20th September, 2016

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)21
Palladium-Catalyzed Cross-Coupling of Aryl Chlorides with Arylsilatranes

Yutaro Yamamoto, Alexandre Baralle, Anaïs Godefroy, Kei Murakami, Hideki Yorimitsu,* and Atsuhiro Osuka

*Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan

Abstract

The cross-coupling reactions of arylsilatranes with readily available and inexpensive aryl chlorides were carried out in toluene/THF at 100 ºC for 3 h in the presence of tetrabutylammonium fluoride as an activator for smooth transmetalation and catalytic amounts of palladium(II) acetate and XPhos.

Supporting Info. (3.1MB)PDF (421KB)

Published online: 16th September, 2016

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)27
Synthesis of 4-Substituted-pyridine-2,6-dicarboxylic Acid Derivatives from Pyruvates and Aldehydes in One Pot

Pandurang V. Chouthaiwale, Sébastien Lapointe, and Fujie Tanaka*

*Chemistry and Chemical Bioengineering Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna, Okinawa 904-0495, Japan

Abstract

4-Substituted-pyridine-2,6-dicarboxylic acid derivatives were synthesized in one pot under mild conditions via the formation of dihydropyran derivatives from pyruvates and aldehydes catalyzed by pyrrolidine-acetic acid, followed by the reaction with ammonium acetate.

Supporting Info. (3.5MB)PDF (475KB)

Published online: 12th September, 2016

Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13530
Synthesis of 2-Alk(or Aryl)oxy- and 2-(Alkyl(or Aryl)sulfanyl)-4H-3,1-benzothiazine Derivatives Carrying a (Z)-Halomethylidene Substutuent at the 4-Position

Kazuhiro Kobayashi* and Takashi Nogi

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

Abstract

2-Alk(or aryl)oxy-4-(Z)-(halomethylidene)-4H-3,1-benzothiazines were synthesized by the reaction of 2-(2,2-dihaloethenyl)phenyl isothiocyanates with sodium alk(or aryl)oxides. Similar treatment of the 2-(2,2- dibromoethenyl)phenyl isothiocyanates with sodium thiolates gave the corresponding 2-(alkyl(or aryl)sulfanyl)-4-(Z)-(bromomethylidene)-4H-3,1- benzothiazines. The above 2-aryloxybenzothiazine derivative underwent clean conversion to 2-aryloxy-4-(Z)-[(arylsulfanyl)methylidene]-4H-3,1-benzothiazines on treatment with sodium arenethiolates. 2-(Arylsulfanyl)-4-(Z)- [(arylsulfanyl)methylidene]-4H-3,1-benzothiazines were also synthesized by the reaction of 2-(2,2-dibromoethenyl)phenyl isothiocyanates with two equivalents of sodium arenethiolates.

PDF (290KB)

Published online: 6th September, 2016

Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13524
Exploring the Synthesis of Deceptively Simple Biginelli Products through N-CN Bond Cleavage

Juan Jesús Nolasco Fidencio, Hulme Ríos-Guerra,* Gilberto González-Villanueva, José Guillermo Penieres-Carrillo, Gustavo Guevara Balcázar, Ma. Inés Nicolás-Vázquez, Hulme Ríos-Guerra, and Francisco Delgado

*Faculty of Higher Cuautitlan Studies, Chemistry Science Department, UNAM, Av. 1° de Mayo s/n Sta. Ma. Gpe. las Torres, Postcode 54740, Cuautitlán Izcalli, Mexico

Abstract

Brønsted-Lowry acid-promoted cleavage of the N-CN bond in 2-cyanoimino-3,4-dihydro-(1H)-pyrimidine is described. Formic acid efficiently activates cyclic N-cyanoguanidines through an O-formylisourea reactive intermediate, leading to chemospecific N-CN bond cleavage of the cyanoimine moiety. This low environmental-load method provides step- and atom-economical access to difficult-to-obtain acid-sensitive Biginelli products in excellent yields.

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Published online: 6th September, 2016

Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13557
Synthesis of Prodelphinidin Trimer Isolated from Cistus Albidus and its Growth Inhibitory Activity Against Human Prostate Cancer Cell Lines

Masataka Mori, Kiriko Matsumoto, Chisato Ishihara, Koichiro Kawaguchi, Sei-ichi Kawahara, Yasunao Hattori, Hiroshi Fujii,* and Hidefumi Makabe*

*Sciences of Functional Foods, Graduate School of Agriculture, Shinshu University, 8304 Minamiminowa-mura, Kamiina-gun, Nagano 399-4598, Japan

Abstract

First synthesis of prodelphinidin trimer (epigallocatechin-gallocatechin-catechin) isolated from Cistus albidus was accomplished from monomeric epigallocatechin electrophile and dimeric gallocatechin-catechin nucleophile. The condensation was worked using AgOTf as a Lewis acid and condensed product was successfully converted into titled compound in good yield. Synthesized compound showed significant growth inhibitory activity against human prostate PC-3 cell lines. Its activity was little bit stronger than that of prodelphinidin B3.

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Published online: 5th September, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13512
Thiosemicarbazides, Potent Reagents for Synthesis of Some New 1,4-Diphenylbenzo[g]quinoxaline-5,10-dione Based Heterocycles

Islam H. El Azab* and Hosam A. Saad

*Department of Chemistry, Faculty of Science, Aswan University, Aswan 81528, Egypt

Abstract

2-(5,10-Dioxo-1,4-diphenyl-3,4-dihydrobenzo[g]quinoxalin-2(1H,5H, 10H)-ylidene)hydrazinecarbothioamide (4) and 2-((4-oxothiazolidin-2-ylidene)- hydrazono)-1,4-diphenyl-1,2,3,4-tetrahydrobenzo[g]quinoxaline-5,10-dione (5), were prepared and utilized as versatile building blocks, via incorporating in series of conversions including cyclocondensation reactions to afford a series of four and fivepharmacophoricmotif conjugates 10, 13, 18, 20, 21, 25, 30, 31, 32, 33 and 34 in fair yields.

PDF (1.7MB)

Published online: 5th September, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13555
A New and Practical Synthesis of Tivozanib

Chunping Zhu, Yongjun Mao,* Han Wang, and Jingli Xu

*College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, 333 Longteng Rd., Songjiang, Shanghai, 201620, China

Abstract

New and improved synthetic route of tivozanib is described on a hectogram scale. An reduction cyclization process to prepare the key intermediate 6,7-dimethoxyquinolin-4-ol from the 3-(dimethylamino)-1-(2-nitrophenyl)prop-2- en-1-one compound at H2/Ni condition is adopted in good result. Commercial available materials, simple reaction and operation are used, including nitration, condensation, hydrogenation, chlorination and so on, to give the final product in 28.7% yield over six steps and 98.9% purity (HPLC).

PDF (684KB)

Published online: 25th August, 2016

Communication | Regular issue | Prepress
DOI: 10.3987/COM-16-13542
Synthesis of Nitriles from Aldehydes with Trimethylphenylammonium Tribromide and Ammonium Acetate

Shinsei Sayama*

*Natural Sciences (Chemistry), Fukushima Medical University, Hikarigaoka, Fukushima, 960-1295, Japan

Abstract

Various aromatic and heterocyclic aldehydes were easily converted to respective nitriles with the combination of trimethylphenylammonium tribromide and ammonium acetate in good yields at room temperature.

Supporting Info. (2.4MB)PDF (1MB)

Published online: 22nd August, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13516
Microwave-Assisted Efficient Synthesis of 4-Substituted Amino-2-methylquinolines Catalyzed by p-Toluenesulfonic Acid

Xiao-qin Wang,* Yuan-hong Cai, Xiao-yang Xie, Cui-ying Huang, Jia-yu Li, Wen-na Chen, Ming-hua He, and Wen-jia Pan*

*School of Pharmacy, Guangdong Medical University, NO1, Xincheng Road, Songshan Lake, Dongguan 523808, China

Abstract

A series of novel 4-subtituted amino-2-methylquinolines (3a-3o) were readily synthesized via the reaction of 4-chloro-2-methylquinoline with amines catalyzed by p-toluenesulfonic acid (TsOH) at 120 for 1 h under microwave-assisted organic synthesis (MAOS) condition. The yields of product 3a-3o were in range of 55-89%. This approach has advantages such as higher yield, shorter reaction time, lower costs, more convenience, and higher efficiency compared to the conventional method. The structures of the products were characterized by using 1H NMR, 13C NMR and HRMS. The reactivity of different amines was discussed.

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Published online: 22nd August, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13513
Three New Benzolactones from the Leaves of Yunnan Local Sun Cured Tobacco and Their Bioactivities

Feng-Mei Zhang, Jian-Jun Xia, Pei-Song Yang, Qin-Peng Shen, Chun-Bo Liu, Pei He, Jia-Qiang Wang, Zhi-Hua Liu,* and Zhong-Tao Ding*

*Key Laboratory of Tobacco Chemistry of Yunnan Province, China Tobacco Yunnan Industry Company, Hongjin Road 181#, Kunming, 650231, China

Abstract

Three new benzolactones, 5-(hydroxymethyl)-6-(2-oxopropyl)isobenzofuran-1(3H)-one (1), 5-methyl-6-(2-oxopropyl)isobenzofuran-1(3H)-one (2), and 5-methoxy-6-(2-oxopropyl)isobenzofuran-1(3H)-one (3), together with three known benzolactones (4-6) were isolated from the leaves of Yunnan local sun cured tobacco. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1-3 were tested for their anti-tobacoo mosaic virus (TMV) activities and compounds 1-6 were tested for their cytotoxicity activities. The results revealed that compound 1-3 showed high anti-TMV activity with inhibition rate of 28.6, 31.2 and 32.7%. These rates are close to that of positive control. Compounds 1-6 also showed moderate-to-weak inhibitory activities against some tested human tumor cell lines with IC50 values in the range of 2.5-8.5 μM.

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Published online: 18th August, 2016

Review | Regular issue | Prepress
DOI: 10.3987/REV-16-845
Diazonaphthoquinones: Synthesis, Reactions and Applications

Dina I. A. Othman and Mitsuru Kitamura*

*Department of Applied Chemistry, Faculty of Engineering, Kyushu Institute of Technology, 1-1 Sensuicho, Tobata, Kitakyushu, 804-8550, Japan

Abstract

This review deals with synthesis and reactions of diazonaphthoquinones during the past 6 years. Various substituted diazonaphthoquinones have been prepared by the reaction of the appropriate naphthol and 2-azido-1,3 dimethyl imidazolinium chloride (ADMC) in short direct pathway. This method is likely to find wide spread uses in organic synthesis and material chemistry such as for preparing photoresists. In this review, different metal catalyzed reactions are investigated and applied successfully to the synthesis of important aromatic compounds. In addition, total synthesis of some natural compounds has been attempted using this recently developed diazo transfer methodology. It is hoped that this compilation, in combination with the previously published literatures on diazo-transfer reaction, will provide useful, up-to-date and comprehensive foundation and reference sources for individuals interested in the same field.

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Published online: 18th August, 2016

Communication | Regular issue | Prepress
DOI: 10.3987/COM-16-13515
Oxidative Dearomatic Cyclization of N-Substituted Benzanilide Derivatives: Conformational Effect of Amide Groups on the Reaction

Kousuke Hayashi, Jun Takayama,* Yousuke Shimano, Meiyan Xuan, Misaki Suda, Hiroyuki Teramae, and Takeshi Sakamoto*

*Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan

Abstract

The synthesis of spirooxindoles with a hypervalent iodine reagent depended on N-substituted benzanilide derivatives as starting materials. Reaction yields of benzanilides containing various N-substituents were discovered to relate to the cis and trans conformations of the amide bond by ab initio molecular orbital calculations at the B3LYP/6-31G(d,p) and MP2/6-31G(d,p) levels, including full geometry optimizations. The relationship between the reaction and conformation of the starting material by quantum chemical calculations was applied to the formal synthesis of SR121463.

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Published online: 5th August, 2016

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)12
Synthesis of γ-Trifluoromethyl Tetronate Derivatives from Squarates

Yoshihiko Yamamoto,* Yosuke Takamizu, Takashi Kurohara, and Masatoshi Shibuya

*Department of Basic Medicinal Sciences, Graduate School of Pharmaceutical Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan

Abstract

Squarates and semisquarates were treated with TMSCF3 in the presence of a catalytic amount of AcONa in DMF at room temperature to afford 4-trifluoromethyl-4-hydroxycyclobutenones. Subsequent oxidative ring expansion of these products was performed using Pb(OAc)4 in the presence of MS 4A in 1,2-dichloroethane at 50 °C to afford γ-trifluoromethyl tetronate derivatives.

Supporting Info. (7MB)PDF (714KB)

Published online: 3rd August, 2016

Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)7
[3+2] Cycloadditions of N-Protected ‘(S)-Diazoproline’ with Selected Acetylenes

Grzegorz Mlostoń,* Paulina Pipiak, and Heinz Heimgartner*

*Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland

Abstract

Acetylene carboxylates and an acetylene phosphonate reacted with N-protected (S)-2-(diazoacetyl)pyrrolidines ((S)-diazoprolines) to give optically active bis-heterocyclic pyrazole derivatives in a regioselective [3+2] cycloaddition. The reactions occurred at 60 °C in THF solution in the absence of a catalyst. However, diethyl ethynylphosphonate reacted significantly slower than the carboxylates. The obtained products were shown to exist in CDCl3 solution at room temperature as mixtures of rotamers. The reactions of diethyl ethynylphosphonate with a selected cyclic α-oxodiazo compound, i.e. 2-diazoacenaphthen-1-one, yielded a fused tricyclic pyrazole derivative.

PDF (316KB)

Published online: 1st August, 2016

Communication | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)11
Oxidative Self-Annulation of 2,5-Diaryl-3,4-diaminothiophene via C–C and C–S Bond Cleavage of the Thiophene Ring: A New Synthesis of an Amino-Substituted Triarylthieno[3,4-b]pyrazines and Their Photophysical Properties

Youhei Takeda,* Satoshi Ueta, and Satoshi Minakata*

*Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan

Abstract

A novel oxidative self-annulation of 2,5-diaryl-3,4-diaminothiophenes that accompanies C–C and C–S bonds cleavage of a thiophene ring to produce 3,5,7-triaryl-2-aminothieno[3,4-b]pyrazines in moderate to good yields has been discovered. Photophysical properties of this new family of thienopyrazines have also been disclosed.

PDF (437KB)

Published online: 1st August, 2016

Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)10
Total Synthesis of Fargesine Using a Platinum-Catalyzed Intramolecular Friedel-Crafts-Type C–H Coupling–Allylic Amination Cascade

Yuito Tanaka, Yuta Suzuki, Yasumasa Hamada, and Tetsuhiro Nemoto*

*Pharmaceutical Chemistry, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo, Chiba, Japan

Abstract

Total synthesis of fargesine was described herein. The synthesis was based on the platinum-catalyzed intramolecular Friedel-Crafts-type C–H coupling–allylic amination cascade to construct the 3,4-fused tricyclic indole skeleton.

Supporting Info. (306KB)PDF (415KB)

Published online: 28th July, 2016

Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)8
N-Heterocyclic Carbene-Promoted [3+2] Cycloaddition of Allenyl Sulfone and Arylidenemalononitriles

Satoru Kuwano,* Toshinobu Masuda, Koki Yamaguchi, and Takayoshi Arai

*Department of Chemistry, Graduate School of Science, Chiba University, , Japan

Abstract

N-Heterocyclic carbenes promote the [3+2] cycloaddition of allenyl sulfone and arylidenemalononitriles, accompanied by 1,2-migration of the sulfonyl group. This reaction provides a new route to highly substituted cyclopentenes.

Supporting Info. (4.9MB)PDF (402KB)

Published online: 13th July, 2016

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)9
Preparation and Biological Activity of Novel Twin-Drug Type C2-Symmetrical Cyclic Phenylboronic Acid Derivatives

Makoto Furutachi, Ayumi Ejima, Reika Tsuru, Saho Goto, Toshiaki Gondo, Kenta Ako, Saho Fuchigami, Saya Fujii, Arisa Okumura, Ayumi Tozuka, Kazumi Yokomizo, Jian-Rong Zhou, Hiroshi Inao, Yutaro Ono, Nobuhiro Kashige, Fumio Miake, and Kunihiro Sumoto*

*Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan

Abstract

We here report the results of evaluation of antibacterial and anti-herpes simplex virus-1 (HSV-1) activities of a novel twin-drug type C2-symmetrical boronic acid and its pinacol ester derivatives. By using a primitive amide bond formation reaction, various targeted C2-symmetrical cyclic phenylboronic acid derivatives were obtained from the reactions of commercially available amino-substituted phenylboronic acid derivatives and diacid dichlorides. The C2-symmetrical bivalent molecule 3bd containing two cyclic phenylboronic acid pinacol ester moieties and a flexible hexamethylene linker showed both antibacterial activity (S. aureus) and anti-HSV-1 activity. The corresponding boronic acid derivative 3dd showed neither antibacterial nor anti-HSV-1 activity, indicating the importance of two pinacol ester functionalities.

PDF (355KB)

Published online: 30th June, 2016

Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)4
Isolation and Evaluation of Hedgehog Inhibitors from Christmas Grass (Themeda arguens)

Tatsuro Yoneyama, Midori A. Arai,* Takashi Koyano, Thaworn Kowithayakorn, and Masami Ishibashi*

*Department of Natural Products Chemistry, Graduate School of Pharmaceutical Science, Chiba University, 1-8-1 Inohana, Chuo, Chiba, Japan

Abstract

The hedgehog (Hh) signaling pathway is an important regulator of embryonic development, tissue patterning, cellular proliferation and differentiation. However, aberrant activation of the pathway is associated with tumorigenesis. In this study, the Hh signal inhibitory activity of plant extracts was measured with a cell-based assay system that targets GLI1-mediated transcription. Activity guided analysis of MeOH extracts of christmas grass (Themeda arguens) led to the isolation of four inhibitory compounds: aciculatin (1), 7-de-O-methylaciculatin (2), 8-C-β-D-boivinopyranosylapigenin (3) and aciculatinone (4). Compound 1 strongly inhibited Hh/GLI1-mediated transcriptional activity with an IC50 value of 1.8 μM, and disrupted the formation of the GLI1-DNA complex by EMSA. 1 and 3 were cytotoxic for human prostate (DU-145) and breast (MCF-7) cancer cells. These compounds may serve as new tools for the molecular dissection of Hh pathway activation.

Supporting Info. (129KB)PDF (1.6MB)

Published online: 22nd June, 2016

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)5
Synthesis of (±)-Cephalanthrin A Using Baeyer-Villiger Oxidation

Tomoki Itoh, Takumi Abe, Tominari Choshi, Takashi Nishiyama, and Minoru Ishikura*

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

Abstract

Indoloquinazoline alkaloid (±)-cephalanthrin A was synthesized through the Baeyer-Villiger oxidation of the phenyl ketone derived from aldol reaction of tryptanthrin and acetophenone.

PDF (360KB)

Published online: 9th June, 2016

Communication | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)1
A Water-Soluble Cavitand Sequesters 2-Nonenal, the Odor Component of the Elderly

Yang Yu, Simone Mosca, and Julius Rebek, Jr.*

*Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, U.S.A.

Abstract

Long chain aldehydes are principal components of odor in older populations. Here we show that a synthetic container molecule, a deep water-soluble cavitand forms complexes in aqueous (D2O) solution. The cavitands bind the aldehyde in a compressed conformation that reduces exposure to the medium. The aldehyde is extracted from the complex by tetrachloroethane and sodium dodecyl sulfate, chemical agents of dry cleaning or laundering, respectively. The large-scale synthesis of the cavitand opens possibilities for its attachment to clothing fibers.

PDF (252KB)

Published online: 7th June, 2016

Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)3
Synthesis of 3-Bromoquinoline-2(1H)-thiones and 2-(Alkylsulfanyl)-3-bromoquinolines Based on the Reaction of 2-(2,2-Dibromoethenyl)phenyl Isothiocayanates with Butyllithium

Kazuhiro Kobayashi,* Ippei Nozawa, and Takashi Nogi

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

Abstract

The synthesis of 3-bromoquinoline-2(1H)-thiones and 2-(alkylsulfanyl)-3-bromoquinolines from readily available starting materials was accomplished. Thus, 2-(2,2-dibromoethenyl)phenyl isothiocyanates were treated with butyllithium to afford, after aqueous workup, 3-bromoquinoline-2(1H)-thiones. When haloalkanes were added prior to workup, 2-(alkylsulfanyl)-3-bromoquinolines were obtained. An elaboration of one of these compounds to a thieno[2,3-b]quinoline derivative and one-pot preparation of 3-substituted quinoline-2(1H)-thiones were also achieved.

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Published online: 2nd June, 2016

Paper | Special issue | Prepress
DOI: 10.3987/COM-16-S(S)2
Synthetic Study towards Construction of Potential Scaffold of Antitumor Agents Andrastins

Shuqiang Yin, Kenji Sugimoto, Hideo Nemoto, and Yuji Matsuya*

*Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, Sugitani 2630, Toyama, 930-0194, Japan

Abstract

For a construction of potential scaffold of antitumor agents andrastins, intramolecular Diels-Alder reaction of the triene composed of trans-fused AB ring with tethered D ring was examined. The reaction in refluxing toluene afforded a desired cis-fused hydrindane skeleton, the relative stereochemistries of which were unambiguously determined by X-ray crystallographic analysis.

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Published online: 28th March, 2016

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)18
Synthesis of Phenantroline and Indole Based Hybrid Cyclophane Derivatives via Ring-closing Metathesis

Sambasivarao Kotha,* Mukesh E. Shirbhate, Ajay Kumar Chinnam, and Gaddameedi Sreevani

*Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai - 400076, India

Abstract

Here, we report new phenanthroline-based cyclophane derivatives via Fischer indolization and ring-closing metathesis (RCM) as key steps. Grignard addition of 2 and subsequent autoxidation gave the phenanthroline dione derivative 3. Further, Fischer indolization of 3 followed by RCM under mild reaction conditions gave indole and phenanthroline containing hybrid cyclophanes such as 6a and 6b.

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Published online: 1st February, 2016

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)48
Synthetic Studies toward Concavine: Synthesis of The BCD Ring Syste

Yosuke Komori, Akitoshi Kozen, and Masahiro Toyota*

*Team TOYOTA, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuencho, Sakai, Osaka 593-8531, Japan

Abstract

The BCD ring system of concavine is realized stereoselectively using a palladium-catalyzed cycloalkenylation to synthesize the CD ring and an intramolecular aza-Michael reaction to append the third ring.

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Published online: 12th January, 2016

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)26
Antiproliferative Activity of Hybrid Compounds Between 6-Methoxy-3-(4-Methoxyphenyl)-1H-Indole and 3-Phenylpiperidine Against HCT-116 and HL-60 Cells

Noriyuki Hatae,* Takashi Nishiyama, Shoko Tamura, Ryohei Yamamoto, Ayaka Matsui, Hiroki Shinchi, Satoshi Hibino, Chiaki Okada, Teruki Yoshimura, Tominari Choshi, and Eiko Toyota*

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

Abstract

Indole derivatives have been potential anticancer drugs. Methyl 6-methoxy-3-(4-methoxyphenyl)-1H-indole-2-carboxylate, in particular, was reported as a potent antiproliferative agent against MCF-7, NCI-H460, and A375-C5 tumor cells. In this study, the 3-arylindole-2-carboxylate exhibited weak activity against HCT-116 colon tumor and HL-60 promyelocytic leukemia cells. To develop the potent antiproliferative indole derivatives against HCT-116 and HL-60 cells, we synthesized 6-methoxy-3-(4-methoxyphenyl)-1H-indoles with various 2-substituents and assessed their activity. The 4-phenylpiperidine derivatives attenuated the tumor cells viability. Furthermore, their calculated structure resembled that of the antiproliferative loperamide derivatives.

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Published online: 7th January, 2016

Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)46
Chemistry of Polyhalogenated Nitrobutadienes, 15: Synthesis of Novel 4-Nitro-3-amino-1H-pyrazole-5-carbaldehydes and Pyrazolo[3,4-f]indazole-4,8-diones

Viktor A. Zapol'skii, Jan C. Namyslo, Mimoza Gjikaj, and Dieter E. Kaufmann*

*Institute of Organic Chemistry, Clausthal University of Technology, Leibnizstrasse 6, D-38678 Clausthal-Zellerfeld, Germany

Abstract

Condensation of 1-amino-1-(1H-benzo[d][1,2,3]triazol-1-yl)-3,4,4-trichloro-2-nitrobuta-1,3-dienes 3a-e with methylhydrazine leads to a series of uniquely persubstituted 4nitropyrazoles 4a-e bearing a dichloromethyl substituent in 5-position. Subsequent hydrolysis of this group applying aqueous sulfuric acid then gives interesting push-pull – substituted pyrazole-5-carbaldehydes 5a-e. Upon hydrolysis of 4a-e at harsher reaction conditions different pyrazolo[3,4-f]indazole-4,8-diones were also formed. A mechanism of the homo-condensation of carbaldehydes 5a,d to the indazole derivatives 8-13 is proposed, and as an example the structure of 3,7-bis(dimethylamino)-1,6-dimethylpyrazolo[3,4-f]indazole-4,8(1H,6H)-dione (9) has been confirmed by X-ray analysis.

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Published online: 6th January, 2016

Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)42
Formal Total Synthesis of Artocarpin

Isao Mizota, Kana Taniguchi, and Makoto Shimizu*

*Department of Chemistry for Materials, Graduate School of Engineering, Mie University, 1577 Kurimamachiya-cho Tsu, Mie 514-8507, Japan

Abstract

A formal total synthesis of artocarpin was achieved via selective demethylation, iodination, followed by Suzuki-Miyaura coupling reaction of the key flavone derivative. It took only 7 steps in the overall yield of 55% starting from commercially available 3,5-dimethoxyphenol.

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Published online: 3rd December, 2015

Communication | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)54
Unexpected Highly Chemoselective Nucleophilic Substitution Reaction of 4-Dimethylamino-2-methoxy-3-trifluoroacetylquinoline with Various Nucleophiles

Etsuji Okada,* Mizuki Hatakenaka, Yoshinori Takezawa, and Keisuke Iwakuni

*Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan

Abstract

Aromatic nucleophilic substitution reaction of 4-dimethyl- amino-2-methoxy-3-trifluoroacetylquinoline with various nucleophiles (NuH) such as amines, thiols, and alcohols proceeded chemoselectively to give the corresponding Me2N-Nu exchanged products, 2-methoxy-3-trifluoroacetyl- 4-quinolylamines, sulfides, and ethers without any formation of MeO-Nu exchanged products in spite of the common knowledge that alkoxy group is the better leaving group than amino group.

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Published online: 1st December, 2015

Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)55
Synthesis of 7,7′-Linked-bis-indoles via 7-Tryptamines

Hakan Kandemir, Ibrahim F. Sengul, Christopher R. Gardner, Eryn L. Werry, Melissa L. Barron, Michael Kassiou, Naresh Kumar, and David StClair Black*

*School of Chemistry, The University of New South Wales, Sydney 2052, Australia

Abstract

The synthesis of 7-tryptamines was accomplished via the reduction of 7-nitrovinylindoles which were developed by the condensation of indole-7-carbaldehydes with nitromethane and ammonium acetate. 7-Tryptamines were subsequently used for the construction of 2,3-disubstituted and 3-substituted 7,7-linked-bis-indoles.

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