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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: 24th June, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13487
Catalyst-Free Synthesis of 1-Phenylnaphtho[2,1-b]furan Derivatives under Microwave Irradiation

Baolong Wang, Jinfu Zhang, Jianhong Liao, Yiyuan Peng, and Hua Zheng*

*School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, 122 Luoshi Road,Wuhan,Hubei 430070, China

Abstract

An environmentally benign and efficient method has been developed for the synthesis of naphtho[2,1-b]furan from (E)-(2-nitrovinyl)benzene and naphthalen-2-ol in brine media under catalyst-free conditions through microwave-assisted technology. The advantages of this process are that it is catalyst-free, has an easy work-up, provides good yields, and uses brine as the solvent which is considered to be relatively environmentally benign.

Supporting Info. (2.5MB)PDF (993KB)

Published online: 24th June, 2016

Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13483
Synthesis, Characterization and Cytotoxicity Evaluation of Some Novel Pyrazole, Pyrimidine and Isoxazoloe Drivatives Containing Benzothiazole Moiety

Khaled. S. Mohamed,* Hala M. Refat, and Nada A. H. Mohamed

*Engineering Chemistry Department, Higher Institute for Engineering and Technology, New Damietta, New Damietta 34518, Egypt

Abstract

The 2-(2-benzothiazolyl)-3-(2-methoxy-1-naphthyl)acrylonitrile (3) was used as precursor for the synthesis of some novel pyrazole, isoxazole, pyrimidine derivatives and other related products containing benzothiazole moiety via the reaction of compound 3 with appropriate chemical reagents. The structures of the newly synthesized products were confirmed by elemental analyses, IR, 1H-NMR, 13C-NMR and mass spectral data. These compounds were screened for their antitumor activities. Compound 7 displayed promising in vitro antitumor activity in the four cell lines assay.

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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: 20th June, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13470
DABCO-Catalyzed Green Synthesis of Thiazole and 1,3-Thiazine Derivatives Linked to Benzofuran

Sobhi M. Gomha, Mohamed G. Badrey, and Wael A. A. Arafa*

*Department Of Chemistry, Fayoum University, Fayoum 12975, Egypt

Abstract

An eco-friendly and simple procedure for the reaction of 2-(1-(benzofuran-2-yl)ethylidene)hydrazinecarbothioamide with arylidenemalononitriles and hydrazonoyl halides catalyzed by using sterically hindered organic base, 1,4-diazabicyclo[2.2.2]octane (DABCO) was described. This new protocol has the advantage of good yields and short reaction times. The structure of the newly synthesized compounds was elucidated via elemental analyses and spectral data.

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Published online: 20th June, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13482
Two New 2-Arylbenzofurans from the Stems of Nicotiana tabacum and Their Bioactivities

Pei-Song Yang, Wei Zhang, Xiao-Feng Shen, Xin-Lin Wang, Chao Li, Xiao-Wei Gong, Xu-Dong Zheng, Dong-Lai Zhu, and Jia-Qiang Wang*

*School of Chemical Science and Technology, Yunnan University, Kunming 650091, China

Abstract

Two new 2-arylbenzofurans, 4-(7-methoxy-3,5-dimethyl-benzofuran-2-yl)phenol (1), 4-(6-methoxy-3,5-dimethylbenzofuran-2-yl)-phenol (2), together with two known 2-arylbenzofurans (3 and 4) were isolated from the stems of Nicotiana tabacum. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1-4 were tested for their anti-TMV and cytotoxicity activities. The results showed that compound 2 exhibited high anti-TMV activities with inhibition rates of 36.4% at the concentration of 20 μM. This rate is higher than that of positive control. Compounds 1-4 showed moderate-to-weak cytotoxicities against some tested human tumor cell lines with IC50 values in the range of 2.2–8.4 μM.

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Published online: 20th June, 2016

Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13491
One-Pot and Three-Component Synthesis, Characterization and Biological Evaluation of Some New 1,2,4-Triazine-coumarins

Guang-cheng Wang,* Jing Wang, Dian-xiong He, Xin Li, Juan Li, and Zhi-yun Peng

*College of Chemistry and Chemical Engineering, Jishou University, Jishou University, Jishou 416000, China

Abstract

A series of 1,2,4-triazine-coumarins were prepared by a one-pot, three-component condensation of 1,2-diarylethane-1,2-diones, thiosemicarbazide and 2-coumaryloxy-methyloxiranes using K2CO3 as a catalyst in aqueous medium. This three-component reaction offers several advantages such as simple procedure, environmentally friendly and high yields. The resulting products were characterized by 1H NMR, 13C NMR and melting points. Furthermore, all newly synthesized compounds were evaluated for their α-glucosidase inhibitory activity. As a result, the majority of the screened compounds displayed potent inhibitory activity with IC50 values in the range of 32.57±0.21 to 148.77±3.23 μM, when compared to the standard acarbose (IC50 = 876.14±2.46 μM).

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Published online: 17th June, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13497
Oxidative Synthesis of Isoxazoline-N-oxide from Optically Active Nitro Alcohols

Takaaki Moriyama, Takuji Kawamoto, Hidemitsu Uno, and Akio Kamimura*

*Department of Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, , Japan

Abstract

Treatment of optically active 6-nitrohex-1-en-3-ols with Ag2O and iodine under basic conditions resulted in an oxidative intramolecular cyclization reaction to give isoxazoline-N-oxide along with bicyclo[3.1.0]hexane. The stereoselectivity and chemoselectivity of the reaction depended on the configuration of the stereogenic center adjacent to the alkenyl group. The structure was determined by X-ray crystallographic analyses as well as coupling constants from NMR data. Stereochemical preferences in the transition structure of the reaction are discussed.

Supporting Info. (1.7MB)PDF (389KB)

Published online: 13th June, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13437
Preparation and Electrochemical Behavior of N-Substituted Phenothiazine Oxide

Hideki Hayashi* and Take-aki Koizumi

*Organic Materials Laboratory, Nagoya Municipal Industrial Research Institute, 3-4-41, Rokuban, Atsuta-ku, Nagoya 456-0058, Japan

Abstract

The chemical properties of promazine oxide (Prom-O) and promazine (Prom) were compared. Cyclic voltammetry (CV) experiments showed a higher oxidation potential of Prom-O compared to that of Prom. The results of CV measurements also suggested the potential applicability of Prom-O as an n-type semiconductor.

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Published online: 9th June, 2016

Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13467
A Simple and Convenient Synthesis of Isolated Fused Heterocycles Based on: 6-Phenyl-2-thioxo-2,3-dihydropyrimidin-4(5H)-one and 5-Acetyl-6-phenyl-2-thioxo-2,3-dihydropyrimidin-4(5H)-one

Mohamed Ahmed Mahmoud Abdel Reheim,* Ibrahim Saad Abdel Hafiz, and Mohamed Ahmed Elian

*Department of Chemistry, Faculty of Science, Suez Canal Univeristy, Arish 45511, Egypt

Abstract

The reaction of 6-phenyl-2-thioxo-2,3-dihydropyrimidin-4(5H)-one 1 with acetylchloride in acetic anhydride in the presence of sodium acetate afforded 5-acetyl-6-phenyl-2-thioxo-2,3-dihydropyrimidin-4(5H)-one 2 which reacted with bromine, hydrazine hydrate, phenylhydrazine, cyanothioacetamide, aldehydes and (malononitrile/sulfur) to give 2-thioxo-2,3-dihydropyrimidine derivatives 4, 7a,b, 8, 10 and 11 respectively. In the present investigation 6-phenyl-2-thioxo-2,3-dihydropyrimidin-4(5H)-one 1 was reacted with chloroacetylchloride yielded the corresponding compound 13. Compound 1 was reacted with some electrophilic reagents such as (benzylidene cyanothioacetamide derivatives, 2-cyano-2-cyclopentylethanethioamide, 2-cyano-2-cyclohexylethanethioamide and aromatic diazonium salts) to give compounds 23, 27a,b and 35 respectively. The newly synthesized heterocycles were characterized on the basis of their chemical properties and spectral data.

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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: 9th June, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13499
A Convenient Synthetic Route for Substituted 1-(Aryldiazenyl)Imidazo[1,5-a]Pyridine

Mustafa M. El-Abadelah,* Hamdallah A. Hodali, Monther S. Zreid, Firas F. Awwadi, Mohammed M. Abadleh, and Wolfgang Voelter

*Department of Chemistry, Faculty of Science, The University of Jordan, Amman 11942, Jordan

Abstract

In the presence of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), model 2-(N'-aryl)picolinohydrazonamides 7, 8 (derived from interaction of the respective ethyl glycinate and (2-pyridyl)methylamine with the particular hydrazonoyl chloride) underwent didehydrogenation with concomitant heterocyclization to deliver the corresponding 1-(aryldiazenyl)imidazo- [1,5-a]pyridines 9, 10. Structures of the latter bicyclic systems are deduced from spectral data and confirmed by X-ray diffraction analysis of the Pd-complex 11, derived from 9.

PDF (2.7MB)

Published online: 9th June, 2016

Short Paper | Regular issue | Prepress
DOI: 10.3987/COM-16-13498
Intramolecular 1,3-Dipolar Cycloaddition of Diazido-terminal Dialkynes: Synthesis of New Polyoxyethylene Fused exo-Bis(1,2,3-triazolo-1,4-oxazines)

Nejib Hussein Mekni*

*Organic Structural Chemistry Laboratory, Synthesis and Physico-Chemical Studies, Department of Chemistry, University of Tunis El-Manar, 2092 Tunis, Tunisia

Abstract

The synthesis of new tetraheterocyclic 1,5-disubstituted exo-heterocyclic polyoxyethylene bis(1,2,3-triazolo-1,4-oxazine) is achieved through nucleophilic azide ion ring opening reaction on polyoxyethylene dioxiranes, followed by an O-propargylation, then thermal uncatalyzed 1,3-dipolar intramolecular cycloaddition.

PDF (1.1MB)

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: 3rd June, 2016

Review | Regular issue | Prepress
DOI: 10.3987/REV-16-842
Development of Solvent-Driven Iron-Catalyzed Reactions

Toshiyuki Itoh*

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

Abstract

The possibility of solvent-driven iron-catalyzed reactions has been investigated using ionic liquids and acetonitrile as key solvents. Three iron-catalyzed reactions, the intramolecular cyclization of cyclopropane dithioacetals, the [2+2]-cycloaddition of (trans)-anethole, and the [2+3]-type cycloaddition of styrene derivatives with 1,4-benzoquinone, were first developed using acetonitrile as solvent in the presence of 3~5 mol% of Fe(ClO4)3Al2O3 or Fe(BF4)26H2O under air conditions. In particular, we found the rapid cycloaddition of iron-catalyzed [2+3]-type cycloaddition of styrene derivatives with 1,4-benzoquinone when the reaction was carried out in an ionic liquid which contained [PF6] or [Tf2N] anion. Homo-coupling reaction of aryl or alkynyl Grignard reagent was next discovered using 1 mol% of FeCl3 as catalyst and the reaction also proceeded very rapidly in an ionic liquid. We also found that 3~5 mol% of Fe(ClO4)2Al2O3 or Fe(BF4)26H2O-successfully catalyzed Friedel-Crafts type alkylation of indoles or pyrroles with vinyl ketones or α-aryl-β-silylalcohol. In particular, the reaction of chiral α-aryl-β-silylalcohol with indole using Fe(ClO4)3nH2O as catalyst proceeded with retention of the configuration of stereochemistry of the hydroxyl group. Then, we discovered the first example of iron-catalyzed enantioselective C-S bond formation via Michael addition of thiols to (E)-3-crotonoyloxazolidin-2-one using 10 mol% of Fe(BF4)2/Pybox. We further demonstrated that Fe(ClO4)3Al2O3-catalyzed the Nazarov type cyclizations of thiophene, pyrrole, indole, benzofuran, and benzo[b]thiophene derivatives using ionic liquids as solvent. Solvents have been recognized as a by-player in chemical reactions in the process of “optimization of reaction conditions”. However, further investigation of the solvent-driven iron-catalyzed reaction will allow discovery of useful reactions for organic syntheses.

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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: 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.

PDF (996KB)

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.

PDF (351KB)

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.

PDF (392KB)

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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Published online: 27th November, 2015

Paper | Regular issue | Prepress
DOI: 10.3987/COM-15-13324
P-Stereogenic Diphosphacrowns: Facile Incorporation of Aromatic Rings

Ryosuke Kato, Hiroyuki Watanabe, Yasuhiro Morisaki,* and Yoshiki Chujo*

*Applied Chemistry for Environment, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan

Abstract

P-Stereogenic diphosphacrowns containing naphthalene and pyridine rings were synthesized. Facile incorporation of aromatic rings, and chains of different lengths, into the diphosphacrown skeleton was achieved by altering the electrophile in our previously reported synthetic method. Pyridine-containing diphosphacrown exhibited chiral recognition ability for chiral ammonium salts and carboxylic acids. This is the first example of chiral recognition using P-stereogenic diphosphacrowns. 1H and 31P NMR spectra indicated that the nitrogen, oxygen, and chiral phosphorus atoms contributed to the chiral recognition cooperatively.

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Published online: 17th November, 2015

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)63
Synthesis of Noroxymorphone By N-Demethylation/ Intramolecular Acylation of Oxymorphone Catalyzed By Iron(II) Chloride

Mary Ann A. Endoma-Arias, Ales Machara, D. Phillip Cox, and Tomas Hudlicky*

*Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way St. Catharines, Ontario, L2R 3K4, Canada

Abstract

Oxymorphone was converted to its 3,14-diacetate and subjected to Fe(II)/t-BuOOH-catalyzed N-demethylation that occurred with concomitant acyl migration from the C-14 hydroxyl to the N-17 nitrogen. The resulting diacetyl compound was hydrolyzed in dilute sulfuric acid to noroxymorphone in good yield.

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Published online: 4th November, 2015

Communication | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)61
Natural Product Inspired Enantioselective Synthesis of Hexahydro-Aza-Pentalenones

Pierre-Yves Dakas, Herbert Waldmann, and Kamal Kumar*

*Chemical Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn Str. 11 44227, Germany

Abstract

An asymmetric synthesis of structurally complex hexahydro-aza-pentalenones embodying four consecutive stereogenic centers including two quaternary centers, one of which is an all-carbon-quaternary center, was developed with an enantioselective [3+2] cycloaddition reaction of azomethine ylides and substituted cyclopentenones.

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Published online: 30th October, 2015

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)53
Practical Synthesis of Tricyclic Lactam Model of Antitumor Renieramycin-Saframycin Natural Products

Masashi Yokoya, Akiya Fujino, Ayako Yaguchi, Miku Yamazaki, and Naoki Saito*

*Department of Medicinal Chemistry, Pharmaceutical Chemistry, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan

Abstract

A practical synthesis of the tricyclic lactam model compound of antitumor renieramycin-saframycin natural product starting from 2-hydroxy-4,5-dimethoxy-3-methylbenzaldehyde in eleven steps was described. A tosyl group was used for protection of a phenol during this transformation. The overall yield of the target compound was 23%.

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Published online: 30th October, 2015

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)32
Unsymmetrical Phthalocyanines With One TTF unit and Octylthio or Octylsulfonyl Groups: Their Optical and Electrochemical Properties

Takeshi Kimura,* Jasmin Kang, and Shidsuko Nakajo

*Center for Instrumental Analysis, Iwate University, 4-3-5 Ueda, Morioka, Iwate 020-8551, Japan

Abstract

Unsymmetrical phthalocyanines fused with a TTF unit and six octylthio or six octylsulfonyl groups were prepared by the reaction of a mixture of phthalonitrile fused with a TTF unit and 4,5-di(octylthio)- or 4,5-di(octyl- sulfonyl)phthalonitrile. The optical and electrochemical properties of the products were determined by UV-vis absorption spectra, cyclic voltammetry, and ESR spectra.

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Published online: 30th October, 2015

Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)45
New Synthesis of Antitumor Drug Cabozantinib

Gerhard Laus, Erwin Schreiner, Sven Nerdinger,* Volker Kahlenberg, Klaus Wurst, Stefan Vergeiner, and Herwig Schottenberger

*Sandoz GmbH, Biochemiestrasse 10, 6250 Kundl , Austria

Abstract

The heterocyclic antitumor drug cabozantinib was synthesized by condensation of 4-(6,7-dimethoxyquinolin-4-yloxy)aniline and methyl 1-(4-fluorophenylcarbamoyl)cyclopropanecarboxylate in the presence of two equivalents of sodium methoxide and azeotropic removal of methanol. In turn, the key intermediate methyl 1-(4-fluorophenylcarbamoyl)cyclopropanecarboxylate was prepared from 4-fluoroaniline and dimethyl 1,1-cyclopropanedicarboxylate in the presence of one equivalent of sodium methoxide. Four crystal structures of intermediates and a byproduct were determined.

Supporting Info. (156KB)PDF (4.7MB)

Published online: 29th October, 2015

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)13
Chemical Reactivity and Application of 4-Alkylidene-3H-pyrazol-3-ones: Synthesis and Antifungal Activity of Polysubstituted Pyrazoles

Hiroshi Maruoka,* Masataka Hokao, Nobuhiro Kashige, Eiichi Masumoto, Fumi Okabe, Reiko Tanaka, Fumio Miake, Toshihiro Fujioka, and Kenji Yamagata

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

Abstract

Chemical reactivity and application of 4-alkylidene-3H-pyrazol-3-ones are described. Furthermore, twelve of the newly synthesized O-substituted pyrazoles were evaluated for their antifungal activity in vitro against Candida albicans and Saccharomyces cerevisiae.

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Published online: 26th October, 2015

Short Paper | Special issue | Prepress
DOI: 10.3987/COM-15-S(T)33
Ring-contractive and -Closing Skeletal Rearrangement of 1,1’-Binaphthalene-2,2’-Diamines (Binams) Induced by An Iodine-Containing Oxidant: Synthesis of Spiro[Benzo[e]Indole-1,1'- inden]-2-Amines and Application to An Aiee-active Bf2 Complex

Masato Okazaki, Kosuke Takahashi, Youhei Takeda, and Satoshi Minakata*

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

Abstract

An iodine-containing oxidant-induced ring-contractive and -closing skeletal rearrangement of 1,1’-binaphthalene-2,2’-diamines (BINAMs) to afford spiro[benzo[e]indole-1,1'-inden]-2-amines has been discovered. Furthermore, a spiro product was successfully transformed into a novel luminescent spirocyclic BF2 complex.

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