Faculty Profiles - ABE Takumi

Papers - ABE Takumi

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Direct C4-Benzylation of Indoles via Tandem Benzyl Claisen/Cope Rearrangements Reviewed

Takumi Abe, Yuta Kosaka, Miku Asano, Natsuki Harasawa, Akane Mishina, Misato Nagasue, Yuri Sugimoto, Kazuaki Katakawa, Shunsuke Sueki, Masahiro Anada, Koji Yamada

Organic Letters 21 ( 3 ) 826 - 829 2019.2

Total synthesis of pyrano[3,2-e]indole alkaloid fontanesine B by a double cyclization strategy Reviewed

Tomoki Itoh, Yuusuke Chiba, Shunsuke Kawaguchi, Yuki Koitaya, Yuuma Yoneta, Koji Yamada, Takumi Abe

RSC Advances 9 ( 18 ) 10420 - 10424 2019

Authorship：Last author,　Corresponding author Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry ({RSC})

<p>The regioselective synthesis of pyrano[3,2-<italic>e</italic>]indole alkaloid fontanesine B have been accomplished by C4 Pictet–Spengler cyclization and Bischler–Napieralski-type cyclization of a trichloromethyl carbamate.</p>

DOI： 10.1039/C9RA02321F

Biomimetic Synthesis of Iheyamine A from Spirocyclic Oxindoles Reviewed

Takumi Abe, Koji Yamada, Syuhei Satake

HETEROCYCLES 99 ( 0 ) 379 - 379 2019

Double "open and Shut" Transformation of γ-Carbolines Triggered by Ammonium Salts: One-Pot Synthesis of Multiheterocyclic Compounds Reviewed

Takumi Abe, Haruka Shimizu, Shiori Takada, Takahiro Tanaka, Mai Yoshikawa, Koji Yamada

Organic Letters 20 ( 6 ) 1589 - 1592 2018.3

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society

A novel cascade reaction of indole-2,3-epoxide equivalents with γ-carbolines by utilizing a double "open and shut" transformation to access multiheterocyclic compounds containing both isotryptamines and pyrimido[1,6-a]indoles has been developed. This strategy utilizes the in situ formation of a bulky quaternary ammonium salt via ammonium exchange, which undergoes Hofmann elimination/vinylogous Mannich/retro-Mannich/cyclization cascade sequences.

DOI： 10.1021/acs.orglett.8b00332

Dehydrative Mannich-Type Reaction for the Synthesis of Azepinobisindole Alkaloid Iheyamine A Reviewed

Takumi Abe, Koji Yamada

Organic Letters 20 ( 5 ) 1469 - 1472 2018.3

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society

A concise synthesis of the azepinobisindole alkaloid iheyamine A from an indole-2,3-epoxide equivalent has been achieved. This method features a formal C3 electrophilic reaction of an indole-2,3-epoxide equivalent with tryptamine to form a 3-aminoindoline and a novel In-catalyzed dehydrative Mannich-type reaction of the hemiaminal to give the azepinobisindole core.

DOI： 10.1021/acs.orglett.8b00330

Synthesis of Phaitanthrin E and Tryptanthrin through Amination/Cyclization Cascade Reviewed

Takumi Abe, Masaru Terasaki

Helvetica Chimica Acta 101 ( 2 ) e1700284 2018.2

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley Blackwell

Phaitanthrin E was biomimetically synthesized from methyl indole-3-carboxylate and methyl anthranilate or anthranilic acid using the ester group as an activating group. The reaction proceeds through NCS-mediated dearomatization/TFA-catalyzed protonation of indolenine/C(2) amination/Et3N-promoted aromatization and cyclization in one-pot procedure. This method is capable of converting simple biomass materials to phaitanthrin E. The synthesis not only allows assessment of antiproliferative activity, but also affords experimental support for the hypothetical biosynthetic pathway of phaitanthrin E. The resulting phaitanthrin E derivatives were evaluated for in vitro antiproliferative activity against human colorectal cancer cells (DLD-1). The biogenetic intermediate of phaitanthrin E showed higher antiproliferative activity than the natural product, phaitanthrin E. Furthermore, a concise synthesis of tryptanthrin is also accomplished from indole-3-carbaldehyde and methyl anthranilate using the aldehyde group as an activating group.

DOI： 10.1002/hlca.201700284

Nazarov cyclization of an indolyl vinyl ketone promoted by acetyl chloride and sodium iodide: Formal synthesis of Bruceolline e Reviewed

Takumi Abe

Heterocycles 96 ( 3 ) 490 - 500 2018

Authorship：Lead author,　Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Institute of Heterocyclic Chemistry

An acetyl chloride/NaI-mediated Nazarov-type cyclization of an indolyl vinyl ketone was developed to give a cyclopenta[b]indole in high yield. An acyl Finkelstein reaction is a key feature for this unprecedented Nazarov-type cyclization.

DOI： 10.3987/COM-18-13866

Synthesis of Indoloquinazoline Alkaloids Using Cascade Reactions Reviewed

Abe Takumi

Journal of Synthetic Organic Chemistry, Japan 76 ( 8 ) 802 - 809 2018

Authorship：Lead author,　Last author,　Corresponding author Language：Japanese Publisher：The Society of Synthetic Organic Chemistry, Japan

<p>We describe the total synthesis of indolo[2,1-b]quinazoline alkaloids tryptanthrin (1a), candidine (2), phaitanthrins A (3), B (4), C (5), cruciferane (8), and cephalanthrin A (9) using oxidative cascade sequences as the key step. Phaitanthrin E (7a) was synthesized by a novel methodology that features a concise approach involving the intermolecular condensation and intramolecular aryl C-H amination mediated by Cu-complexes to construct the indolo[2,1-b]quinazoline core. Moreover, an acid catalyzed one-pot synthesis of phaitanthrin E (7a) via intermolecular amination/intramolecular cyclization cascade using NCS was also developed.</p>

DOI： 10.5059/yukigoseikyokaishi.76.802

Radical Cyclizations of Aryl Bromides for Synthesis of Cyclopenta[b]Indoles from Vince Lactam Reviewed

Takumi Abe, Tsuyoshi Morita, Koji Yamada

HETEROCYCLES 97 ( 0 ) 141 - 141 2018

An Ullmann N-arylation/2-amidation cascade by self-relay copper catalysis: one-pot synthesis of indolo[1,2-a]quinazolinones Reviewed

Takumi Abe, Yuka Takahashi, Yuki Matsubara, Koji Yamada

ORGANIC CHEMISTRY FRONTIERS 4 ( 11 ) 2124 - 2127 2017.11

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

We have developed a self-relay copper(I)-catalyzed Ullmann N-arylation/2-amidation cascade to form functionalized indolo[1,2-a]quinazolinones in one-pot from easily available indoles with 2-bromobenzamides. This novel transformation features a tandem process of Ullmann-type coupling, activation of indolenine, and 2-amidation in the presence of a single copper catalyst. In addition, among the substituents of indoles at the C3 position, methyl carboxylate could act as an activating group in this Ullmann N-arylation/2-amidation cascade.

DOI： 10.1039/c7qo00549k

C4 Pictet-Spengler Reactions for the Synthesis of Core Structures in Hyrtiazepine Alkaloids Reviewed

Takumi Abe, Tomohiro Haruyama, Koji Yamada

SYNTHESIS-STUTTGART 49 ( 18 ) 4141 - 4150 2017.9

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：GEORG THIEME VERLAG KG

The hyrtiazepine alkaloids are a family of bisindole natural products that have the azepinoindole backbone. We developed a biomimetic approach by constructing the azepinoindole core in a one-pot manner through 1,4-diazabicyclo[2.2.2]octane/2,2,2-trifluoroethanol (DABCO/TFE) promoted Pictet-Spengler reaction onto the C-4 position of tryptophan. This strategy allowed the synthesis of common key structures of these families. The key intermediate can be converted into the 3H-pyrano[2,3-b:5,6-e']diindol intermediate present in hyrtimomines A and B, as well as the azepinoindole core present in fargesine.

DOI： 10.1055/s-0036-1588438

2-Hydroxyindoline-3-triethylammonium Bromide: A Reagent for Formal C3-Electrophilic Reactions of Indoles Reviewed

Takumi Abe, Takuro Suzuki, Masahiro Anada, Shigeki Matsunaga, Koji Yamada

ORGANIC LETTERS 19 ( 16 ) 4275 - 4278 2017.8

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

A novel indole-2,3-epoxide equivalent, 2-hydroxyindbline-3-triethylammonium bromide, was found, to be a convenient reagent for formal C3-electrophilic reactions of indoles with various nudeophiles. By taking advantage of the nudeophilie character of the oxygen of the 2-hydroxyindo-line the interrupted retro-Claisen interrupted Feist - Benary reactions, with 1,3-dicarbonyl compounds Were efficiently achieved.

DOI： 10.1021/acs.orglett.7b01940

A copper-catalyzed Ritter-type cascade via iminoketene for the synthesis of quinazolin-4(3H)-ones and diazocines Reviewed

Takumi Abe, Koshiro Kida, Koji Yamada

CHEMICAL COMMUNICATIONS 53 ( 31 ) 4362 - 4365 2017.4

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

We have developed a copper-catalyzed Ritter-type reaction/cyclization cascade of anthranilic acids and nitriles, affording the quinazolin-4(3H)-ones. The cascade proceeds through a Ritter-type reaction capturing the iminoketene intermediates by nitriles. Furthermore, we found a novel Ritter-type reaction/condensation/intramolecular anti-Markovnikov hydroamination cascade, providing access to functionalized diazocines in one-pot.

DOI： 10.1039/c7cc01406f

Concise Syntheses of Hyrtioreticulins C and D via a C-4 Pictet-Spengler Reaction: Revised Signs of Specific Rotations Reviewed

Takumi Abe, Koji Yamada

JOURNAL OF NATURAL PRODUCTS 80 ( 2 ) 241 - 245 2017.2

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

The first syntheses of hyrtioreticulins C and D via a Pictet Spengler reaction at the C-4 position of the indole rings are described. The synthesis proceeds in only two steps from commercially available starting materials. In this Communication, the structures of the natural products were confirmed. Furthermore, we revise the signs of the specific rotations of hyrtioreticulins C and D.

DOI： 10.1021/acs.jnatprod.7b00008

One-pot synthesis of fused 2-pyridones from heteroarylacrylic acid via curtius rearrangement & microwave-assisted thermal electrocyclization Reviewed

Takashi Nishiyama, Noriyuki Hatae, Kaori Hayashi, Manami Obata, Kimiko Taninaka, Masahiro Yamane, Shota Oda, Takumi Abe, Minoru Ishikura, Satoshi Hibino, Tominari Choshi

Heterocycles 95 ( 1 ) 251 - 267 2017

Publishing type：Research paper (scientific journal)

©2017 The Japan Institute of Heterocyclic Chemistry. We investigated the one-pot synthesis of several fused 2-pyridone ring systems based on a Curtius rearrangement, followed by a microwave-assisted thermal electrocyclization of a 2-aza-6?-electron system including isocyanate. We synthesized seven heterocyclic compounds containing a fused 2-pyridone ring. In these results, the one-pot synthesis of fused 2-pyridone ring system 5 from (E)-acrylic acids 1 under microwave irradiation conditions was more effective than the conventional reaction conditions in terms of the yield and the reaction time.

DOI： 10.3987/COM-16-S(S)13

SYNTHESIS OF (+/-)-CEPHALANTHRIN A USING BAEYER-VILLIGER OXIDATION

Takumi Abe

Heterocycles 95 ( 1 ) 2017

Amination/Cyclization Cascade by Acid-Catalyzed Activation of Indolenine for the One-Pot Synthesis of Phaitanthrin E Reviewed

Takumi Abe, Koji Yamada

ORGANIC LETTERS 18 ( 24 ) 6504 - 6507 2016.12

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

We have developed a concise one-pot synthesis of phaitanthrin E derivatives, where simple starting materials undergo an acid-catalyzed intermolecular amination/intramolecular cyclization cascade.

DOI： 10.1021/acs.orglett.6b03466

Concise synthesis of carbazole-1,4-quinones and evaluation of their antiproliferative activity against HCT-116 and HL-60 cells Reviewed

Takashi Nishiyama, Noriyuki Hatae, Teruki Yoshimura, Sawa Takaki, Takumi Abe, Minoru Ishikura, Satoshi Hibino, Tominari Choshi

EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY 121 561 - 577 2016.10

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER

We report a convenient synthesis of carbazole-1,4-quinone alkaloid koeniginequinones A and B using a tandem ring-closing metathesis with the dehydrogenation reaction sequence under an O-2 atmosphere as an important step. Using this method, carbazole-1,4-quinones substituted at the 5-, 6-, 7-, and/or 8-positions have been synthesized. Moreover, 24 compounds, including koeniginequinones A and B, have been evaluated for their antiproliferative activity against HCT-116 and HL-60 cells, and the 6-nitro analog exhibited the most potent activity against both tumor cell types. (C) 2016 Elsevier Masson SAS. All rights reserved.

DOI： 10.1016/j.ejmech.2016.05.065

Synthesis of (±)-Cephalanthrin A using Baeyer-Villiger Oxidation

Takumi Abe

Heterocycles 2016.6

A ONE-POT SYNTHESIS OF PHAITANTHRIN E THROUGH INTERMOLECULAR CONDENSATION/INTRAMOLECULAR ARYL C-H AMINATION CASCADE Reviewed

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

HETEROCYCLES 92 ( 6 ) 1132 - 1136 2016.6

Language：English Publishing type：Research paper (scientific journal) Publisher：PERGAMON-ELSEVIER SCIENCE LTD

A one-pot synthesis of phaitanthrin E starting from methyl indole-3-carboxylate and isatoic anhydride through intermolecular condensation/intramolecular aryl C-H amination cascade was developed.

DOI： 10.3987/COM-16-13465

Other Link： http://orcid.org/0000-0003-1729-1097

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