研究者詳細 - 門田　功

論文 - 門田　功

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Stereoselective Synthesis of the Proposed C79-C104 Fragment of Symbiodinolide

Hiroyoshi Takamura, Takayuki Fujiwara, Yohei Kawakubo, Isao Kadota, Daisuke Uemura

Chemistry - A European Journal 22 ( 6 ) 1979 - 1983 2016年2月

Inside Back Cover: Stereodivergent Synthesis and Stereochemical Reassignment of the C79-C104 Fragment of Symbiodinolide (Chem. Eur. J. 6/2016)

Hiroyoshi Takamura, Takayuki Fujiwara, Yohei Kawakubo, Isao Kadota, Daisuke Uemura

Chemistry - A European Journal 22 ( 6 ) 2183 - 2183 2016年2月

Stereodivergent Synthesis and Stereochemical Reassignment of the C79-C104 Fragment of Symbiodinolide

Hiroyoshi Takamura, Takayuki Fujiwara, Yohei Kawakubo, Isao Kadota, Daisuke Uemura

Chemistry - A European Journal 22 ( 6 ) 1984 - 1996 2016年2月

Convergent synthesis of the EFGH ring system of ciguatoxin CTX3C 査読

Isao Kadota, Yuki Sato, Naoya Fujita, Hiroyoshi Takamura, Yoshinori Yamamoto

TETRAHEDRON 71 ( 37 ) 6547 - 6558 2015年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

Convergent synthesis of the EFGH ring segment of ciguatoxin CTX3C was investigated by using the intramolecular allylation of an alpha-chloroacetoxy ether and/or O,S-acetal, and subsequent ring-closing metathesis. A new method for the preparation of gamma-alkoxyallylstannane is also described. (C) 2015 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2015.04.106

Stereodivergent Synthesis and Relative Stereostructure of the C1–C13 Fragment of Symbiodinolide

Hiroyoshi Takamura, Hiroko Wada, Mao Ogino, Takahiro Kikuchi, Isao Kadota, Daisuke Uemura

The Journal of Organic Chemistry 80 ( 6 ) 3111 - 3123 2015年3月

STEREOCONTROLLED SYNTHESIS OF THE C1-C7 FRAGMENT OF ENIGMAZOLE A 査読

Takayuki Kishi, Yuka Fujisawa, Hiroyoshi Takamura, Isao Kadota

HETEROCYCLES 89 ( 2 ) 515 - 522 2014年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

An enantio- and stereoselective synthesis of the C1-C7 fragment of enigmazole A is described. The three asymmetric centers of the molecule were constructed efficiently by using Evans chiral auxiliary protocol.

DOI： 10.3987/COM-13-12905

IMPROVDED SYNTHESIS OF THE A-E RING SEGMENT OF CIGUATOXIN CTX3C 査読

Kengo Shiroma, Hiroki Asakura, Tokihiro Tanaka, Hiroyoshi Takamura, Isao Kadota

HETEROCYCLES 88 ( 2 ) 969 - 973 2014年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

The improved synthesis of the A-E ring segment of ciguatoxin CTX3C was performed via a highly convergent approach based on intramolecular allylation-RCM methodology.

DOI： 10.3987/COM-13-S(S)106

Stereoselective synthesis of the C79-C97 fragment of symbiodinolide

Hiroyoshi Takamura, Takayuki Fujiwara, Isao Kadota, Daisuke Uemura

BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY 9 1931 - 1935 2013年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：BEILSTEIN-INSTITUT

Symbiodinolide is a polyol marine natural product with a molecular weight of 2860. Herein, a streamlined synthesis of the C79-C97 fragment of symbiodinolide is described. In the synthetic route, a spiroacetalization, a Julia-Kocienski olefination, and a Sharpless asymmetric dihydroxylation were utilized as the key transformations.

DOI： 10.3762/bjoc.9.228

Total synthesis, structural elucidation, and structure-cytotoxic activity relationship of (-)-gummiferol 査読

Takamura Hiroyoshi, Wada Hiroko, Lu Nan, Ohno Osamu, Suenaga Kiyotake, Kadota Isao

Journal of Organic Chemistry 78 ( 6 ) 2443 - 2454 2013年3月

記述言語：英語掲載種別：研究論文（学術雑誌）

<p>A highly stereoselective and stereodivergent synthesis of two possible diastereomers of (-)-gummiferol was achieved, wherein the stepwise epoxidation and Cadiot-Chodkiewicz reaction were utilized for the construction of the diepoxide moiety and triacetylene part, respectively. Detailed comparison of their <sup>1</sup>H and <sup>13</sup>C NMR data and specific rotation with those of the natural product unambiguously elucidated the absolute stereostructure of gummiferol. In addition, the cytotoxic activity of the synthesized gummiferol, its stereoisomers, and its truncated analogues was evaluated, which clearly indicates that (1) the absolute configuration of the diepoxide moiety has little influence on the cytotoxic activity against human cancer cells and (2) the triacetylene unit is the crucial structural element required for exerting the cytotoxic activity.</p>

DOI： 10.1021/jo302665c

Total Synthesis of Two Possible Diastereomers of (+)-Sarcophytonolide C and Its Structural Elucidation

Hiroyoshi Takamura, Kohei Iwamoto, Eiji Nakao, Isao Kadota

ORGANIC LETTERS 15 ( 5 ) 1108 - 1111 2013年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

Stereoselective and parallel total syntheses of two possible diastereomers of (+)-sarcophytonolide C have been accomplished. Macrolactonization and transannular ring-closing metathesis (RCM) were the key transformations. Detailed comparisons of their H-1 and C-13 NMR data and specific rotation with those of the natural product allowed the absolute configuration of (+)-sarcophytonolide C to be determined.

DOI： 10.1021/ol400157s

SYNTHESIS OF THE E RING SEGMENT OF CIGUATOXIN CTX3C VIA THE NEGISHI COUPLING OF CYCLIC KETENE ACETAL TRIFLATES 査読

Kengo Shiroma, Hiroyoshi Takamura, Isao Kadota

HETEROCYCLES 86 ( 2 ) 997 - 1001 2012年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

Stereocontrolled synthesis of the E ring segment of ciguatoxin CTX3C was performed via the Negishi coupling of cyclic ketene acetal triflates. Transformation of 8-membered lactones to the corresponding ketene acetal triflates was found to be affected by the protective groups of the substrates.

DOI： 10.3987/COM-12-S(N)117

Stereoselective synthesis of the C94-C104 fragment of symbiodinolide 査読

Hiroyoshi Takamura, Kosuke Tsuda, Yohei Kawakubo, Isao Kadota, Daisuke Uemura

Tetrahedron Letters 53 ( 33 ) 4317 - 4319 2012年8月

記述言語：英語掲載種別：研究論文（学術雑誌）

Stereoselective synthesis of the C94-C104 fragment of symbiodinolide which is a polyol marine natural product with a molecular weight of 2860 has been accomplished. The synthetic route features Achmatowicz rearrangement and RuO 4-catalyzed dihydroxylation for the construction of the tetrahydropyran moiety and the dithiane addition to the aldehyde for the introduction of the side chain. © 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2012.06.005

A convergent synthesis of the right-hand fragment of ciguatoxin CTX3C 査読

Hiroyoshi Takamura, Takashi Abe, Naoki Nishiuma, Rie Fujiwara, Takahiko Tsukeshiba, Isao Kadota

TETRAHEDRON 68 ( 10 ) 2245 - 2260 2012年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

A convergent synthesis of the right-hand fragment of ciguatoxin CTX3C was investigated. The first and second generation stereocontrolled syntheses of the LM ring fragment were achieved via spiroacetalization as a key step, respectively. The polyether framework of the HIJKLM ring fragment was constructed in a convergent manner by using intramolecular allylation, ring-closing metathesis, and stereoselective hydrogenation to form the 36-methyl substituent as the key transformations. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2012.01.071

Convergent Synthesis of the HIJKLM Ring System of Ciguatoxin CTX3C 査読

Hiroyoshi Takamura, Naoki Nishiuma, Takashi Abe, Isao Kadota

ORGANIC LETTERS 13 ( 17 ) 4704 - 4707 2011年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

The HIJKLM ring system of ciguatozin CTX3C was synthesized in a convergent manner. The key steps were a conjugate addition/alkylation sequence, spiroacetalization, intramolecular allylation, ring-closing metathesis, and hydrogenation to form the 36-alpha-methyl substituent.

DOI： 10.1021/ol2019136

Total synthesis and absolute configuration of (-)-gummiferol 査読

Hiroyoshi Takamura, Hiroko Wada, Nan Lu, Isao Kadota

Organic Letters 13 ( 14 ) 3644 - 3647 2011年7月

記述言語：英語掲載種別：研究論文（学術雑誌）

Stereoselective synthesis of two possible diastereomers of (-)-gummiferol was accomplished by the stepwise epoxidation and Cadiot-Chodkiewicz reaction as the key transformations. Detailed comparison of their 1H and 13C NMR data and specific rotation with those of the natural product led to the absolute structural elucidation of (-)-gummiferol. © 2011 American Chemical Society.

DOI： 10.1021/ol201301b

Stereocontrolled synthesis and structural confirmation of the C14 - C24 degraded fragment of symbiodinolide 査読

Hiroyoshi Takamura, Yuichiro Kadonaga, Isao Kadota, Daisuke Uemura

Tetrahedron 66 ( 38 ) 7569 - 7576 2010年9月

記述言語：英語掲載種別：研究論文（学術雑誌）

The C14-C24 fragment of symbiodinolide possessing the 17R/18R/21R absolute configuration, which was obtained as one of the degraded products of symbiodinolide, and its diastereomer possessing the 17R/18S/21R absolute stereochemistry were synthesized stereoselectively from cis-2-butene-1,4-diol, respectively. The detailed comparison of the synthetic products with the degraded product in the spectroscopic data confirmed unambiguously that the stereostructure of the C14 - C24 fragment was 17R, 18R, and 21R. © 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2010.07.045

A new method for the stereoselective construction of angular methyl group of fuzed cyclic ethers 査読

Isao Kadota, Takayuki Kishi, Yuka Fujisawa, Yuji Yamagami, Hiroyoshi Takamura

TETRAHEDRON LETTERS 51 ( 30 ) 3960 - 3961 2010年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

A convenient method for the stereoselective construction of angular methyl group of fuzed cyclic ethers is described. Reactions of mixed thioacetals with Me(2)Zn/Zn(OTO)(2) afforded the corresponding methylated products in good yields. Various protective groups such as MOM ether, benzylidene acetal, TBS ether, and pivaloyl group were stable under the reaction conditions. (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2010.05.109

Total synthesis of brevenal 査読

Hiroyoshi Takamura, Yuji Yamagami, Takayuki Kishi, Shigetoshi Kikuchi, Yuichi Nakamura, Isao Kadota, Yoshinori Yamamoto

TETRAHEDRON 66 ( 29 ) 5329 - 5344 2010年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

The convergent total synthesis of brevenal, a non-toxic brevetoxin antagonist, has been achieved. The ABC ring segment and the E ring precursor were connected by the intramolecular allylation followed by ring-closing metathesis to furnish the pentacyclic ether compound. An alternative route to the key synthetic intermediate, a pentacyclic ether core, was also examined. The right- and left-hand side chains were introduced by Wittig and Horner-Wadsworth-Emmons reactions, respectively, to furnish brevenal (1). (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2010.05.069

Stereoselective synthesis of the C14-C24 degraded fragment of symbiodinolide 査読

Hiroyoshi Takamura, Yuichiro Kadonaga, Isao Kadota, Daisuke Uemura

TETRAHEDRON LETTERS 51 ( 19 ) 2603 - 2605 2010年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD

Symbiodinolide is a polyol macrolide isolated from the marine dinoflagellate Symbiodinium sp. in 2007. The C14-C24 fragment of symbiodinolide possessing the 17R/18R/21R absolute configuration, which was obtained as one of the degraded products of symbiodinolide, was synthesized stereoselectively from cis-2-butene-1,4-diol. The detailed comparison of the synthetic product with the degraded product in the spectroscopic data confirmed that the stereostructure of the C14-C24 fragment was 17R, 18R, and 21R. (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2010.03.014

38 ブレベナールの全合成(口頭発表の部)

山神雄司, 菊池重俊, 中村祐一, 岸敬之, 高村浩由, 門田功, 山本嘉則

天然有機化合物討論会講演要旨集 ( 51 ) 223 - 228 2009年9月

記述言語：日本語出版者・発行元：天然有機化合物討論会

Brevenal (1), a new family of marine polycyclic ether, was isolated from the Florida red tide dinoflagellate Karenia brevis by Baden and co-workers in 2004. This compound inhibits the binding of tritiated dihydrobrebetoxin-B to the voltage-sensitive sodium channels in a concentration dependent manner and acts as a nontoxic brevetoxin antagonist. Moreover, a significiant improvement of tracheal mucus velocity was observed in an animal model asthma. As well as the novel biological activities, the unique structural features have attracted attention of synthetic chemists. In 2006, the first total synthesis and structure revision of 1 were reported by Sasaki and co-workers. In this paper, we wish to report eht recent results and our efforts on the total synthesis of brevenal (1). The ABC ring segment 3 was prepared from the known compound 7 the B-alkyl Suzuki-Miyahara coupling of the phosphate 11 and the alkylborate from the iodine 5. Direct methylation of the O,S-acetal 16 was performed by using Me_2Zn/Zn(OTf)_2 in highly stereoselective manner. The ABC ring fragment obtained and the known alchol 4 were connected by our own synthetic strategy including the intramolecular allylation of α-acetoxy ether followed by ring-closing metathesis to furnish the pentacyclic ether 2. The right hand diene was introduced by the Nicolaoua's protocol. Construction of the left hand side chain, highly substituted dienyl moiety, was archieved by the modified Horner-Wadsworth-Emmons reaction with the phosphonate 33, newly developed, to afford the dienyl ether 34 as the sole product. A seris of functional transformation and deprotections of 34 furnished brevenal (1). The synthetic 1 exhiibited physical and spectroscopic data identical to those reported previously.

DOI： 10.24496/tennenyuki.51.0_223

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