Faculty Profiles - YAMAGUCHI, Shigehiro

Papers - YAMAGUCHI, Shigehiro

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Monitoring Fluorescence Response of Amphiphilic Flapping Molecules in Compressed Monolayers at the Air-Water Interface Reviewed

Waka Nakanishi, Shohei Saito, Naoki Sakamoto, Akihiro Kashiwagi, Shigehiro Yamaguchi, Hideki Sakai, Katsuhiko Ariga

CHEMISTRY-AN ASIAN JOURNAL Vol. 14 ( 16 ) page： 2869 - 2876 2019.8

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

The air-water interface, which is the boundary of two phases with a large difference in polarity, gives a distinct environment compared with bulk water or air. Since the interface provides a field for various biomolecules to work, it is important to understand the molecular behaviors at the interface. Here, polarity-independent flapping viscosity probes (FLAP) equipped with hydrophobic/hydrophilic substituents have been synthesized and studied at the air-water interface. In situ fluorescence (FL), which is related to the internal motion and orientation, of three different FLAPs were investigated at the interface, and the internal motion of the molecule was indicated to be suppressed at the interface. In addition, the molecular response was compared with that of conventional viscosity probes (molecular rotors), which indicates the different behaviors of FLAP probably due to the distinct molecular orientation as well as molecular motion.

DOI： 10.1002/asia.201900769

A photostable fluorescent marker for the superresolution live imaging of the dynamic structure of the mitochondrial cristae Reviewed International journal Open Access

Chenguang Wang, Masayasu Taki, Yoshikatsu Sato, Yasushi Tamura, Hideyuki Yaginuma, Yasushi Okada, Shigehiro Yamaguchi

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Vol. 116 ( 32 ) page： 15817 - 15822 2019.8

Language：English Publishing type：Research paper (scientific journal) Publisher：NATL ACAD SCIENCES

Stimulation emission depletion (STED) microscopy enables ultrastructural imaging of organelle dynamics with a high spatiotemporal resolution in living cells. For the visualization of the mitochondria! membrane dynamics in STED microscopy, rationally designed mitochondrial fluorescent markers with enhanced photostability are required. Herein, we report the development of a superphotostable fluorescent labeling reagent with long fluorescence lifetime, whose design is based on a structurally reinforced naphthophosphole fluorophore that is conjugated with an electron-donating diphenylamino group. The combination of long-lived fluorescence and superphotostable features of the fluorophore allowed us to selectively capture the ultrastructures of the mitochondria! cristae with a resolution of similar to 60 nm when depleted at 660 nm. This chemical tool provides morphological information of the cristae, which has so far only been observed in fixed cells using electron microscopy. Moreover, this method gives information about the dynamic ultrastructures such as the intermembrane fusion in different mitochondria as well as the intercristae mergence in a single mitochondrion during the apoptosis-like mitochondrial swelling process.

DOI： 10.1073/pnas.1905924116

Structurally Constrained Boron-, Nitrogen-, Silicon-, and Phosphorus-Centered Polycyclic pi-Conjugated Systems

Masato Hirai, Naoki Tanaka, Mika Sakai, Shigehiro Yamaguchi

CHEMICAL REVIEWS Vol. 119 ( 14 ) page： 8291 - 8331 2019.7

Language：Japanese Publisher：AMER CHEMICAL SOC

Incorporation of main group elements into the it-conjugated frameworks is a sophisticated strategy to alter the fundamental nature of the parent conjugated pi systems, giving rise to attractive electronic and photophysical properties that are otherwise inaccessible with classic carbon- or metal-based materials. Out of all irconjugated heterocycles, those that are structurally constrained by tethered aryl substituents surrounding the main group center deserve a great deal of attention because not only do they commonly possess the maximum efficiency of it -conjugation and intermolecular interaction, but they also enjoy remarkable thermal and morphological stabilities that are especially crucial for solid-state performances. In certain cases, elucidation of the behavior of such compounds may additionally provide sufficient perspective toward graphene materials doped with main group elements, which are widely considered as potential next -generation optoelectronic materials. In this review, we will specifically focus on historical developments of structurally constrained polycyclic it -electron systems particularly of those with boron, nitrogen, silicon, or phosphorus atoms annulated directly into the center of 2r -conjugated systems.

DOI： 10.1021/acs.chemrev.8b00637

Planarized B,N-phenylated dibenzoazaborine with a carbazole substructure: electronic impact of the structural constraint

Mikinori Ando, Mika Sakai, Naoki Ando, Masato Hirai, Shigehiro Yamaguchi

ORGANIC & BIOMOLECULAR CHEMISTRY Vol. 17 ( 22 ) page： 5500 - 5504 2019.6

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

A B,N-diphenyl-5,10-dihydro-dibenzo-1,4-azaborine, in which both phenyl groups on the boron and nitrogen atoms are planarized to generate a carbazole substructure, was synthesized. The structral constraint around the boron and nitrogen atoms alters the pi-conjugation mode and thus the photophysical and electrochemical properties. Specifically, this structurally constrained dibenzoazaborine showed an intense blue emission with a narrow full width at half maximum. One of its derivatives exhibited near infrared absorption in the one-electron-oxidized state.

DOI： 10.1039/c9ob00934e

Optimization of Aqueous Stability versus pi-Conjugation in Tetracationic Bis(triarylborane) Chromophores: Applications in Live-Cell Fluorescence Imaging

Stefanie Griesbeck, Matthias Ferger, Corinna Czernetzi, Chenguang Wang, Ruediger Bertermann, Alexandra Friedrich, Martin Haehnel, Daniel Sieh, Masayasu Taki, Shigehiro Yamaguchi, Todd B. Marder

CHEMISTRY-A EUROPEAN JOURNAL Vol. 25 ( 32 ) page： 7679 - 7688 2019.6

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

The stability of tetracationic triarylboranes in dilute aqueous solution was investigated by tuning the steric demand of the linker in a (para-(N,N,N-trimethylammonio)xylyl)(2)B-(linker)-B(para-(N,N,N-trimethylammonio)xylyl)(2) structure. With increasing steric bulk of the linker, namely 1,4-phenylene, 2,2 '''-(3,3 '''-dimethyl)-5,2 ':5 ',2 '':5 '',5 '''-quaterthiophene, 9,10-anthracenylene, and 4,4 '''-(5 '-(3,5-dimethylphenyl))(5 ''-(3 ''',5 '''-dimethylphenyl))-2 ',2 ''-bithiophene, the stability of the compounds increased. The anthracene-based chromophore, compound 3M is water-stable for at least 48 h, is nontoxic to cells and exhibits an exceedingly high fluorescence quantum yield of 0.86 in water making it an ideal candidate for confocal live-cell imaging of lysosomes.

DOI： 10.1002/chem.201900723

Tuning the pi-bridge of quadrupolar triarylborane chromophores for one- and two-photon excited fluorescence imaging of lysosomes in live cells Open Access

Griesbeck Stefanie, Michail Evripidis, Wang Chenguang, Ogasawara Hiroaki, Lorenzen Sabine, Gerstner Lukas, Zang Theresa, Nitsch Joern, Sato Yoshikatsu, Bertermann Ruediger, Taki Masayasu, Lambert Christoph, Yamaguchi Shigehiro, Marder Todd B.

CHEMICAL SCIENCE Vol. 10 ( 20 ) page： 5405 - 5422 2019.5

Seeded Polymerization of an Amide-Functionalized Diketopyrrolopyrrole Dye in Aqueous Media

Soichiro Ogi, Natsumi Fukaya, Arifin, Bastian Bjerkem Skjelstad, Yuh Hijikata, Shigehiro Yamaguchi

CHEMISTRY-A EUROPEAN JOURNAL Vol. 25 ( 30 ) page： 7303 - 7307 2019.5

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

The self-assembly of an amide-functionalized dithienyldiketopyrrolopyrrole (DPP) dye in aqueous media was achieved through seed-initiated supramolecular polymerization. Temperature- and time-dependent studies showed that the spontaneous polymerization of the DPP derivative was temporally delayed upon cooling the monomer solution in a methanol/water mixture. Theoretical calculations revealed that an amide-functionalized DPP derivative adopts an energetically favorable folded conformation in the presence of water molecules due to hydration. This conformational change is most likely responsible for the trapping of monomers in the initial stage of the cooperative supramolecular polymerization in aqueous media. However, the monomeric species can selectively interact with externally added fragmented aggregates as seeds through concerted pi-stacking and hydrogen-bonding interactions. Consequently, the time course of the supramolecular polymerization and the morphology of the aggregated state can be controlled, and one-dimensional fibers that exhibit a J-aggregate-like bathochromically shifted absorption band can be obtained.

DOI： 10.1002/chem.201901382

Organic Letters 2.0: A New Beginning

Erick M. Carreira, Kuiling Ding, Margaret Brimble, Hung-wen Liu, Pauline Chiu, Nuno Maulide, Kavirayani R. Prasad, Zhenfeng Xi, Sarah E. Reisman, Shigehiro Yamaguchi, Tobias Ritter, Jin-Quan Yu

ORGANIC LETTERS Vol. 21 ( 1 ) page： 1 - 4 2019.1

Negative fluorescence anisotropy of phosphole oxide-based dyes in nematic liquid crystals Reviewed Open Access

Takuya Ohzono, Tetsuo Yatabe, Chenguang Wang, Aiko Fukazawa, Shigehiro Yamaguchi

COMMUNICATIONS CHEMISTRY Vol. 1 page： 52 2018.9

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：NATURE PUBLISHING GROUP

It is important to understand how solute molecules align in anisotropic media such as liquid crystals and biological membranes. Alignment of fluorescent probes used in polarised fluorescence microscopy is of interest because anisotropy of the medium is indirectly estimated through the fluorescence intensity originating from the transition dipole moments fixed on the molecule. Here we report fluorescence anisotropies of a series of phosphole oxide-based dyes with an elongated pi-conjugated system, along which the transition dipole moment lies, in nematic liquid crystals. We observe that as the number, size and rigidity of substituents protruding from the pi-conjugated plane increase, the transition dipole moment tends to tilt away from the nematic director over the magic angle, similar to 54.7 degrees, showing conspicuous negative fluorescence anisotropy. Analysis of molecular shapes suggests that the substitutions modulate the interaction with the nematic mean field, impacting the direction of the principal molecular axis aligned with the nematic director.

DOI： 10.1038/s42004-018-0055-6

Phosphorus-containing fluorophores for bio-imaging

Yamaguchi Shigehiro

ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY Vol. 256 2018.8

End-Capping pi-Conjugated Systems with Medium-Sized Sulfur-Containing Rings: A Route Towards Solution-Processable Air-Stable Semiconductors Reviewed

Aiko Fukazawa, Yusuke Toda, Masahiro Hayakawa, Anna Sekioka, Hiroyuki Ishii, Toshihiro Okamoto, Jun Takeya, Yuh Hijikata, Shigehiro Yamaguchi

CHEMISTRY-A EUROPEAN JOURNAL Vol. 24 ( 44 ) page： 11503 - 11510 2018.8

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

The sulfur-containing nine-membered heterocycle thiacyclononene (TN) was evaluated as a new type of end-capping group for pi-conjugated systems. A systematic study on TN-capped -oligothiophenes (TNnTs; n=4-7) revealed that the capping with TN, which adopts a bent conformation, imparts the resulting oligothiophenes with drastically increased solubility at approximately 140 degrees C and high electrochemical stability, whereas the electronic structure remains virtually unperturbed. The even-numbered oligothiophenes TN4T and TN6T form characteristic offset herringbone-type packing structures on account of the steric repulsion between the TN rings and the presence of intermolecular nonbonding S center dot center dot center dot S interactions. This packing mode in combination with the high solubility enabled the solution-process fabrication of field-effect transistors based on TN6T, which exhibited a high performance without degradation even upon exposure to air.

DOI： 10.1002/chem.201802656

Donor-pi-Acceptor Type Unsymmetrical Triarylborane-Based Fluorophores: Synthesis, Fluorescence Properties, and Photostability

Masato Ito, Emi Ito, Masato Hirai, Shigehiro Yamaguchi

JOURNAL OF ORGANIC CHEMISTRY Vol. 83 ( 15 ) page： 8449 - 8456 2018.8

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

A two-step synthesis to prepare tricoordinate organoboron compounds bearing three different aryl groups has been developed. After the first aryl substitution to an aryl boronic ester took place, the intermediate species, that is, bis(diarylborinate) species, was isolated as an air- and moisture-stable solid, which allowed the second aryl substitution to carry out in a selective manner. Subsequently, a series of unsymmetrical triarylboranes possessing a sterically bulky aryl group, triarylamine moiety, and para-functionalized phenyl ring was synthesized. Not only did these triarylboranes exhibit remarkable solvent-dependent fluorescence as expected for donor it acceptor (D-pi-A) systems, they were also accompanied by profound persistence against photoirradiation especially for that bearing a 1,3,5-tri-tert-butylphenyl ring. This survey exemplifies that sufficient electronic and steric modification is key to construct photostable D-pi-A type triarylborane-based fluorophores.

DOI： 10.1021/acs.joc.8b01015

Mechanochromic Luminescent Tetrathiazolylthiophenes: Evaluating the Role of Intermolecular Interactions through Pressure and Temperature-Dependent Raman Spectroscopy Open Access

Mosca S., Milani A., Pena-Alvarez M., Yamaguchi S., Hernandez V., Ruiz Delgado M. C., Castiglioni C.

JOURNAL OF PHYSICAL CHEMISTRY C Vol. 122 ( 30 ) page： 17537 - 17543 2018.8

A Highly Photostable Near-Infrared Labeling Agent Based on a Phospha-rhodamine for Long-Term and Deep Imaging Reviewed International journal Open Access

Marek Grzybowski, Masayasu Taki, Kieko Senda, Yoshikatsu Sato, Tetsuro Ariyoshi, Yasushi Okada, Ryosuke Kawakami, Takeshi Imamura, Shigehiro Yamaguchi

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Vol. 57 ( 32 ) page： 10137 - 10141 2018.8

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

Various fluorescence microscopy techniques require bright NIR-emitting fluorophores with high chemical and photostability. Now, the significant performance improvement of phosphorus-substituted rhodamine dyes (PORs) upon substitution at the 9-position with a 2,6-dimethoxyphenyl group is reported. The thus obtained dye PREX 710 was used to stain mitochondria in living cells, which allowed long-term and three-color imaging in the vis-NIR range. Moreover, the high fluorescence longevity of PREX 710 allows tracking a dye-labeled biomolecule by single-molecule microscopy under physiological conditions. Deep imaging of blood vessels in mice brain has also been achieved using the bright NIR-emitting PREX 710-dextran conjugate.

DOI： 10.1002/anie.201804731

Electronic Properties of Substitutionally Boron-Doped Graphene Nanoribbons on a Au(111) Surface Reviewed Open Access

Eduard Carbonell-Sanroma, Aran Garcia-Lekue, Martina Corso, Guillaume Vasseur, Pedro Brandimarte, Jorge Lobo-Checa, Dimas G. de Oteyza, Jingcheng Li, Shigeki Kawai, Shohei Saito, Shigehiro Yamaguchi, J. Enrique Ortega, Daniel Sanchez-Portal, Jose Ignacio Pascual

JOURNAL OF PHYSICAL CHEMISTRY C Vol. 122 ( 28 ) page： 16092 - 16099 2018.7

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

High-quality graphene nanoribbons (GNRs) grown by on-surface synthesis strategies with atomic precision can be controllably doped by inserting heteroatoms or chemical groups in the molecular precursors. Here, we study the electronic structure of armchair GNRs substitutionally doped with di-boron moieties at the center, through a combination of scanning tunneling spectroscopy, angle resolved photoemission, and density functional theory simulations. Boron atoms appear with a small displacement toward the surface, signaling their stronger interactions with the metal. We find two boron-rich flat bands emerging as impurity states inside the GNR band gap, one of them particularly broadened after its hybridization with the gold surface states. In addition, the boron atoms shift the conduction and valence bands of the pristine GNR away from the gap edge and leave unaffected the bands above and below, which become the new frontier bands and have a negligible boron character. This is due to the selective mixing of boron states with GNR bands according to their symmetry. Our results depict that the GNR band structure can be tuned by modifying the separation between di-boron moieties.

DOI： 10.1021/acs.jpcc.8b03748

A planarized B-phenyldibenzoborepin: impact of structural constraint on its electronic properties and Lewis acidity

Naoki Ando, Tomokatsu Kushida, Shigehiro Yamaguchi

CHEMICAL COMMUNICATIONS Vol. 54 ( 41 ) page： 5213 - 5216 2018.5

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

A B-phenyldibenzo[b,f]borepin planarized with two methylene bridges was synthesized. The structural constraint on the B-phenyl group resulted in a bathochromic shift of the absorption and fluorescence properties as well as enhanced Lewis acidity. A donor--acceptor type derivative based on this scaffold exhibited intense fluorescence irrespective of the solvent polarity.

DOI： 10.1039/c8cc02837k

A far-red emitting fluorescent probe for cytosolic Ca2+ion based on phospha-fluorescein scaffold

Ogasawara Hiroaki, Taki Masayasu, Sato Yoshikatsu, Yamaguchi Shigehiro

ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY Vol. 255 2018.3

Near infrared two-photon-excited and -emissive dyes based on a strapped excited-state intramolecular proton-transfer (ESIPT) scaffold Reviewed Open Access

Naoya Suzuki, Kayo Suda, Daisuke Yokogawa, Hirotaka Kitoh-Nishioka, Stephan Irle, Akihiro Ando, Luis M. G. Abegao, Kenji Kamada, Aiko Fukazawa, Shigehiro Yamaguchi

CHEMICAL SCIENCE Vol. 9 ( 10 ) page： 2666 - 2673 2018.3

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

Fluorophores that can undergo excited-state intramolecular proton transfer (ESIPT) represent promising scaffolds for the design of compounds that show red-shifted fluorescence. Herein, we disclose new near infrared-emissive materials based on a dialkylamine-strapped 2,5-dithienylpyrrole as an ESIPT scaffold. The introduction of electron-accepting units to the terminal positions of this scaffold generates acceptor-pi-donor-pi-acceptor (A-pi-D-pi-A) type pi-conjugated compounds. Following the ESIPT, the electron-donating ability of the core scaffold increases, which results in a substantially red-shifted emission in the NIR region, while increasing the oscillator strength. The electron-accepting units play a vital role to achieve intense and red-shifted emission from the ESIPT state. The strapped dialkylamine chain that forms an intramolecular hydrogen bond is also essential to induce the ESIPT. Moreover, an extended A-pi-D-pi-A skeleton enables two-photon excitation with the NIR light. One of the derivatives that satisfy these features, i.e., borylethenyl-substituted 5, exhibited an intense NIR emission in polar solvents such as acetone (lambda(em) = 708 nm, phi(F) = 0.55) with a strong two-photon-absorption band in the NIR region.

DOI： 10.1039/c8sc00066b

Seeded Polymerization through the Interplay of Folding and Aggregation of an Amino-Acid-based Diamide

Soichiro Ogi, Kentaro Matsumoto, Shigehiro Yamaguchi

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Vol. 57 ( 9 ) page： 2339 - 2343 2018.2

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

Amino acid based diamides are widely used as a substructure in supramolecular polymers and are also key components of polypeptides that help to understand protein folding. The interplay of folding and aggregation of a diamide was used to achieve seed-initiated supramolecular polymerization. For that purpose, a pyrene-substituted diamide was synthesized in which pyrene is used as a tracer to monitor the supramolecular polymerization. Thermodynamics and time-dependent studies revealed that the folding of the diamide moiety, via the formation of intramolecular hydrogen bonds, effectively prevents a spontaneous nucleation that leads to supramolecular polymerization. Under such out-of-equilibrium conditions, the addition of seeds successfully initiates the supramolecular polymerization. These results demonstrate the utility of such amino acid based diamides in programmable supramolecular polymerizations.

DOI： 10.1002/anie.201712119

A far-red fluorescent probe based on a phospha-fluorescein scaffold for cytosolic calcium imaging

Hiroaki Ogasawara, Marek Grzybowski, Riho Hosokawa, Yoshikatsu Sato, Masayasu Taki, Shigehiro Yamaguchi

CHEMICAL COMMUNICATIONS Vol. 54 ( 3 ) page： 299 - 302 2018.1

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

The far-red emissive fluorescent probe CaPF-1 based on a phospha-fluorescein scaffold enables the detection of cytosolic calcium ions in living cells. The probe can be excited in the red region (lambda(abs) = 636 nm) and exhibits a sufficiently high fluorescence turn-on response in the far-red region (lambda(em) = 663 nm) upon complexation with calcium ions. The hydrophilic and anionic characteristics of this phospha-fluorescein fluorophore allowed the cytosolic localization of CaPF-1. Moreover, it was possible to visualize histamineinduced calcium oscillation in HeLa cells using CaPF-1.

DOI： 10.1039/c7cc07344e

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