ORCID Profile
0000-0002-4122-3345
Current Organisation
Osaka Research Institute of Industrial Science and Technology
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Publisher: American Chemical Society (ACS)
Date: 08-2010
DOI: 10.1016/J.JASMS.2010.04.005
Abstract: A new approach to the visualization of fatty acids in mouse liver and retinal s les has been developed using silver nanoparticles (AgNPs) in nanoparticle-assisted laser desorption/ionization imaging mass spectrometry (nano-PALDI-IMS) in negative ion mode. So far, IMS analysis has concentrated on main cell components, such as cell membrane phospholipids and cytoskeletal peptides. AgNPs modified with alkylcarboxylate and alkylamine were used for nano-PALDI-IMS to identify fatty acids, such as stearic, oleic, linoleic, arachidonic, and eicosapentaenoic acids, as well as palmitic acid, in mouse liver sections these fatty acids are not detected using 2,5-dihydroxybenzoic acid (DHB) as a matrix. The limit of detection for the determination of palmitic acid was 50 pmol using nano-PALDI-IMS. The nano-PALDI-IMS method is successfully applied to the reconstruction of the ion images of fatty acids in mouse liver sections. We verified the detection of fatty acids in liver tissue sections of mice by analyzing standard lipid s les, which showed that fatty acids were from free fatty acids and dissociated fatty acids from lipids when irradiated with a laser. Additionally, we applied the proposed method to the identification of fatty acids in mouse retinal tissue sections, which enabled us to learn the six-zonal distribution of fatty acids in different layers of the retina. We believe that the current approach using AgNPs in nano-PALDI-IMS could lead to a new strategy to analyze basic biological mechanisms and several diseases through the distribution of fatty acids.
Publisher: American Chemical Society (ACS)
Date: 20-11-2003
DOI: 10.1021/LA035435P
Abstract: Three-dimensional porphyrin-monolayer-protected gold clusters with different chain lengths (MPCs) have been prepared to examine the structure and photophysical properties, in comparison with self-assembled monolayers (SAMs) of the porphyrins on a flat gold surface. The three-dimensional porphyrin MPCs exhibit electrochemical and photophysical properties that are much closer to those of a porphyrin reference compound in solution than those of two-dimensional porphyrin SAMs on the flat gold surface. The three-dimensional architectures of porphyrin MPCs with large surface area have improved the light-harvesting efficiency relative to the corresponding porphyrin SAM on the two-dimensional flat gold surface. Time-resolved single photon counting fluorescence and transient absorption spectroscopic studies have demonstrated that undesirable quenching of the porphyrin excited singlet state via energy transfer to the gold surface of the three-dimensional MPCs is much suppressed, as compared to the quenching of the porphyrin SAMs on the two-dimensional flat gold surface. Both the quenching rate constants of the porphyrin excited singlet state by the surfaces of bulk gold and gold nanoclusters reveal weak chain length dependence of the energy transfer quenching.
Publisher: MDPI AG
Date: 08-2022
Abstract: Five triphenyltriphenylamines with various substituents were investigated as precursors for near-infrared absorbing materials. Cyclic voltammetry (CV) studies showed that they all give stable radical cations in solution. The radical cations obtained by one-electron chemical oxidation of these compounds show strong absorption in the near-infrared region, and the position of the absorption is strongly influenced by the substituent. DFT (density functional theory) calculations suggest that the introduction of stronger electron-donating substituents would result in a smaller HOMO–SOMO energy gap and thus a larger long wavelength shift, which is consistent with the experimental results. On the other hand, strong electron-withdrawing substituents increase the HOMO–SOMO energy gap, resulting in a short wavelength shift. The position of the near-infrared absorption peak of the triphenylamine radical cation can be controlled to the longer or shorter wavelength direction depending on the substituent. A molecular design of near-infrared absorbing dyes utilizing the electronic effects of substituents is described.
Publisher: IEEE
Date: 04-2016
Publisher: MDPI AG
Date: 02-06-2022
Abstract: Four triphenylamines with extended π-systems were synthesized. Cyclic voltammetry (CV) measurements showed that they gave radical cations, which are stable in solution. Radical cations obtained upon one electron chemical oxidation showed strong absorption in the near-infrared region. The radical cations of the naphthalene-substituted derivatives show a maximum absorption wavelength above 1000 nm and are classified as NIR-II dyes. Molecular design rules of novel near-infrared absorbing dyes are described.
Publisher: Walter de Gruyter GmbH
Date: 12-2009
Abstract: A size-controlled synthesis of gold nanoparticles has been developed by the thermolysis of AuCl(SMe 2 ) in the presence of alkylamines at 120 °C. In the procedure, the key intermediate was [Au(NH 2 R) 2 ]Cl, detected by electrospray ionization (ESI) mass spectrometry. This thermally unstable intermediate was reduced by alkylamines under mild conditions to produce alkylamine-capped gold nanoparticles. The average diameters of the gold nanoparticles could be regulated in a range from 4.3 to 6.1 nm by applying primary alkylamines with alkyl chains of different lengths. Larger gold nanoparticles with diameters from 10 to 22 nm were prepared by a combination of alkylamines and alkylcarboxylic acids with various lengths of the alkyl chains. The gold nanoparticles were characterized by transmission electron microscopy (TEM), UV/Vis absorption spectroscopy, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), gas chromatography/mass spectroscopy (GC/MS), and thermogravimetric and differencial thermal analyses (TG/DTA)
Publisher: International Union of Crystallography (IUCr)
Date: 14-07-2020
DOI: 10.1107/S2056989020009317
Abstract: In the title compound, C 24 H 15 Cl 2 N 3 O 2 , one quinoline ring system is essentially planar and the other is slightly bent. An intramolecular O—H...N hydrogen bond involving the hydroxy group and a pyridine N atom forms an S (5) ring motif. In the crystal, two molecules are associated into an inversion dimer with two R 2 2 (7) ring motifs through intermolecular O—H...N and O—H...O hydrogen bonds. The dimers are further linked by an intermolecular C—H...O hydrogen bond and four C—H...π interactions, forming a two-dimensional network parallel to (001).
Publisher: American Chemical Society (ACS)
Date: 28-06-2003
DOI: 10.1021/JP034920Q
Publisher: International Union of Crystallography (IUCr)
Date: 10-09-2019
DOI: 10.1107/S2056989019012350
Abstract: The reaction of bis(3-oxo-1,3-diphenylprop-1-enolato-κ 2 O , O ′)zinc(II), [Zn(dbm) 2 ], with tris[4-(pyridin-3-yl)phenyl]amine (T3PyA) in tetrahydrofuran (THF) afforded the title crystalline coordination polymer, {[Zn(C 15 H 11 O 2 ) 2 (C 33 H 24 N 4 )]·C 4 H 8 O} n . The asymmetric unit contains two independent halves of Zn(dbm) 2 , one T3PyA and one THF. Each Zn II atom is located on an inversion centre and adopts an elongated octahedral coordination geometry, ligated by four O atoms of two dbm ligands in equatorial positions and by two N atoms of pyridine moieties from two different bridging T3PyA ligands in axial positions. The crystal packing shows a one-dimensional polymer chain in which the two pyridyl groups of the T3PyA ligand bridge two independent Zn atoms of Zn(dbm) 2 . In the crystal, the coordination polymer chains are linked via C—H...π interactions into a sheet structure parallel to (010). The sheets are cross-linked via further C—H...π interactions into a three-dimensional network. The solvate THF molecule shows disorder over two sets of atomic sites having occupancies of 0.631 (7) and 0.369 (7).
Publisher: World Scientific Pub Co Pte Lt
Date: 11-2011
DOI: 10.1142/S1088424611004178
Abstract: Multiple photosynthetic reaction centers have successfully been constructed using a supramolecular complex of zinc porphyrin dendrimer [D(ZnP) 16 ] with pyridylnaphthalenediimide (PyNIm) in benzonitrile. The apparent formation constant determined from the fluorescence quenching of the singlet excited state of porphyrin moieties by PyNIm is significantly larger than that determined from the UV-vis spectral change. This indicates that efficient energy migration occurs between the porphyrin units of the dendrimer prior to the electron transfer from the singlet excited state of zinc porphyrin to PyNIm. The charge-separated (CS) state has been successfully detected as the transient absorption spectrum in the laser flash photolysis. The CS lifetime of in the supramolecular complex of D(ZnP) 16 with PyNIm was determined to be 0.83 ms at 298 K.
Publisher: International Union of Crystallography (IUCr)
Date: 18-09-2020
DOI: 10.1107/S2056989020012529
Abstract: In the title molecule, C 48 H 33 N, the central N atom shows no pyramidalization, so that the N atom and the three C atoms bound to the N atom lie almost in the same plane. The three para -phenylene rings bonded to the N atom are in a propeller form. All of the naphthalene ring systems are slightly bent. In the crystal, molecules form an inversion dimer, through two pairs of C—H... π interactions, which further interacts with the adjacent dimer via another two pairs of C—H... π interactions, forming a column structure along the a axis. There are no significant interactions between these column structures.
Publisher: IOP Publishing
Date: 14-06-2018
Publisher: IEEE
Date: 04-2015
Publisher: American Chemical Society (ACS)
Date: 09-2006
DOI: 10.1021/LA0600245
Abstract: Monodispersed silver nanoparticles capped by long-chain alkyl carboxylates were prepared by the reaction of silver carboxylate with tertiary amine at 80 degrees C for 2 h. This approach is a unique, size-controlled synthetic method for the large-scale preparation of silver nanoparticles. Long-chain alkyl carboxylate derived from a precursor acts as a stabilizer to avoid the aggregation of silver nanoparticles and to control particle size. In addition, amine plays an important role both as a reagent to form a thermally unstable, amine-coordinated intermediate, bis(amine)silver(I) carboxylate, and as a mild reducing agent for the intermediate to produce nanoparticles at a low temperature. The silver core and carboxylate-capping ligand of silver nanoparticles were characterized by various techniques such as transmission electron microscopy, optical absorption spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, gas chromatograph mass spectroscopy, and thermogravimetric and differential thermal analysis. The diameter of the nanoparticles can be strongly influenced by the alkyl chain length and the structure of the carboxylate. The average diameters of the silver nanoparticles were controlled to less than 5 nm in the case of silver carboxylate with a single alkyl chain length of 13 or 17 carbon atoms. On the contrary, the average diameters of silver nanoparticles became large and polydisperse in the case of silver carboxylate with a chain length of 7 carbon atoms or a branched chain. In comparing triethylamine with trioctylamine, there was no obvious effect to regulate the size distribution of the nanoparticles because they could not function as a capping ligand of the nanoparticles due to their weak coordination to silver. In addition, the heat treatment of silver nanoparticles in solution rather than in the solid state was effective for the growth of particles while maintaining narrow size distributions.
Publisher: International Union of Crystallography (IUCr)
Date: 15-02-2022
DOI: 10.1107/S2056989022001530
Abstract: In the title compound, [ZnBr 2 (C 22 H 19 ClN 4 O)], the Zn II atom adopts a distorted square-pyramidal coordination geometry, formed by two bromido ligands and three N atoms of the bis(pyridin-2-ylmethyl)amine moiety in the pentadentate ligand containing quinolinol. The Zn II atom is located well above the mean basal plane of the square-based pyramid. The apical position is occupied by a Br atom. The O and N atoms of the quinolinol moiety in the ligand are not coordinated to the Zn II atom. An intramolecular O—H...N hydrogen bond, generating an S (5) ring motif, stabilizes the molecular structure. In the crystal, the molecules are linked by intermolecular C—H...Br hydrogen bonds, generating ribbon structures containing alternating R 2 2 (22) and R 2 2 (14) rings. These ribbons are linked through an intermolecular C—H...Br hydrogen bond, forming a two-dimensional network sheet.
Publisher: Society of Materials Science, Japan
Date: 2015
DOI: 10.2472/JSMS.64.414
Publisher: Physical Society of Japan
Date: 15-02-2013
Publisher: American Chemical Society (ACS)
Date: 2004
DOI: 10.1021/JP036382N
Publisher: International Union of Crystallography (IUCr)
Date: 05-04-2022
DOI: 10.1107/S2056989022003383
Abstract: The title compound, C 33 H 33 N 3 , is a carbazolophane, which is a cyclophane composed of two carbazole fragments. It has a planar chirality but crystallizes as a racemate in the space group P -1. The molecule adopts an anti -configuration, in which two carbazole fragments are partially overlapped. Both carbazole ring systems are slightly bent, with the C atoms at 3-positions showing the largest deviations from the mean planes. The dihedral angle between two carbazole fragments is 5.19 (3)°, allowing an intramolecular slipped π–π interaction [ Cg ... Cg = 3.2514 (8) Å]. In the crystal, the molecules are linked via intermolecular C—H...N hydrogen bonds and C—H...π interactions into a network sheet parallel to the ab plane. The molecules of different sheets form other C—H...π interactions, thus forming a three-dimensional network.
Publisher: IOP Publishing
Date: 05-2013
Abstract: We have successfully printed wires of 5 µm line widths and spaces in copper nanoparticle ink with a super-inkjet printer. The wires show resistivity as low as 8.1 µΩ·cm after sintering at 250 °C in an extremely low oxygen atmosphere generated by an oxygen pump. To our knowledge, this is the first report of micron-scale copper wiring formed by a direct printing method without any masks or templates.
Publisher: International Union of Crystallography (IUCr)
Date: 14-07-2023
DOI: 10.1107/S2056989023005959
Abstract: In the title compound, [Na(C 22 H 19 N 4 O 4 S)(CH 3 CN)] n , the Na I atom adopts a distorted square-pyramidal coordination geometry, formed by one N and one O atom of the qunolinol moiety in the ligand, two O atoms of sulfonate moieties of two adjacent ligands and the N atom of the coordinated acetonitrile solvent. The Na I atom is located well above the mean basal plane of the square-based pyramid. The apical position is occupied by a sulfonate O atom of a neighboring ligand. Three N atoms of the bis(pyridin-2-ylmethyl)amine moiety in the ligand are not coordinated by the sodium atom. The molecule forms an intramolecular bifurcated O—H...[N(tertiary amine),N(pyridine)] hydrogen bond, generating S (6) and S (5) rings. In the crystal, four molecules are linked by four Na—O(sulfonato) bridged coordination bonds, forming a supramolecular centrosymmetric tetramer unit comprising an eight-membered ring, and generating a two-dimensional network sheet. The molecules of different sheets form intermolecular C—H...O hydrogen bonds, and thereby a three-dimensional network structure.
Publisher: Royal Society of Chemistry (RSC)
Date: 2008
DOI: 10.1039/B808433E
Abstract: A simple method for specific colorimetric sensing of aqueous mercury(II) has been developed by using a gold nanoparticle supported by triethylene glycol ligand (Au:S-EG(3)). The unusual kinetic behavior of the sensing process of Hg(2+) and the TEM images of the Au core, as well as the electrospray ionization mass spectroscopic analysis of the analyte solution, have led us to propose a new color changing mechanism that involves ligand abstraction from a gold surface by Hg(2+).
Publisher: AIP Publishing
Date: 12-2014
DOI: 10.1063/1.4903234
Publisher: Springer Science and Business Media LLC
Date: 13-10-2011
Publisher: IOP Publishing
Date: 22-06-2016
Abstract: Crosslinked albumin films, to which L929 cells do not attach by nature, acquire the L929-cell-adhesion capability by irradiation of an atmospheric-pressure plasma jet (APPJ) of He gas. The number of attached cells was 2.6 × 10 4 cells/cm 2 after the APPJ irradiation for 180 s, while conventional UV photolithography, which was performed in our previous work, required 2 h to obtain the same order of magnitude of the number of attached cells. The contact angle of s les decreased steeply from 105 to 38° in the first 10 s irradiation, but decreased quite gradually from 38 to 32° with increasing irradiation time from 10 to 180 s. In contrast to the nonlinear variation in the contact angles, the number of attached cells almost linearly increased from 4.5 × 10 3 to 2.6 × 10 4 cells/cm 2 with increasing treatment time. X-ray photoelectron spectroscopy of the s les indicated that hydrophilic functional groups of C–C=O gradually formed with increasing APPJ irradiation time up to 180 s. These results suggest that the cell-adhesion capability of the crosslinked albumin films is not simply explained by the decrease in contact angle but also by the formation of oxidized functional groups on the surface. The effects of UV and vacuum UV light from APPJ were negligible, which indicates that the formation of oxidized functional groups on the surface is not caused by photon-assisted surface reactions but by reactions involving chemically active species supplied from APPJ.
Publisher: The Chemical Society of Japan
Date: 05-06-2020
DOI: 10.1246/CL.200161
Publisher: Elsevier BV
Date: 08-2006
DOI: 10.1016/J.JCIS.2006.03.041
Abstract: Controlled thermolysis of silver alkylcarboxylates with primary alkylamines was investigated as a facile synthetic method of silver nanoparticles. A series of silver alkylcarboxylates, C(7)H(15)COOAg, C(13)H(27)COOAg, and C(17)H(35)COOAg, have been prepared and the thermolysis of those silver alkylcarboxylates in the presence of various alkylamines, C(8)H(17)NH(2), C(12)H(25)NH(2), and C(18)H(37)NH(2), with no use of solvent was conducted at 120 or 180 degrees C for 5 h, providing spherical silver nanoparticles stabilized by alkylcarboxylates and alkylamines. The size and dispersibility of nanoparticles depend on the alkyl chain length of the precursors, alkylcarboxylates and alkylamines.
Publisher: Royal Society of Chemistry (RSC)
Date: 2003
DOI: 10.1039/B309588F
Publisher: American Chemical Society (ACS)
Date: 06-10-2005
DOI: 10.1021/CM0515000
Publisher: American Chemical Society (ACS)
Date: 08-2004
DOI: 10.1021/JP048404R
Publisher: International Union of Crystallography (IUCr)
Date: 31-03-2022
DOI: 10.1107/S2056989022002973
Abstract: The molecule of the title compound, C 16 H 14 N 2 O, contains an essentially planar indole ring system and a phenyl ring. In the crystal, the molecules are linked by a weak intermolecular C—H...O hydrogen bond and C—H...π interactions, forming a one-dimensional column structure along the b- axis direction. These columns are linked by other C—H...π interactions, forming a two-dimensional network structure.
Publisher: IOP Publishing
Date: 13-06-2013
Publisher: Elsevier BV
Date: 2022
Publisher: Wiley
Date: 24-06-2004
Abstract: A meso,meso-linked porphyrin trimer, (ZnP)3, as a light-harvesting chromophore, has been incorporated for the first time into a photosynthetic multistep electron-transfer model including ferrocene (Fc) as an electron donor and fullerene (C60) as an electron acceptor, to construct the ferrocene-meso,meso-linked porphyrin trimer-fullerene system Fc-(ZnP)3-C60. Photoirradiation of Fc-(ZnP)3-C60 results in photoinduced electron transfer from both the singlet and triplet excited states of the porphyrin trimer, 1(ZnP)3* and 3(ZnP)3*, to the C60 moiety to produce the porphyrin trimer radical cation-C60 radical anion pair, Fc-(ZnP)3*+-C60*-. Subsequent formation of the final charge-separated state Fc+-(ZnP)3-C60*- was confirmed by the transient absorption spectra observed by pico- and nanosecond time-resolved laser flash photolysis. The final charge-separated state decays, obeying first-order kinetics, with a long lifetime (0.53 s in DMF at 163 K) that is comparable with that of the natural bacterial photosynthetic reaction center. More importantly, the quantum yield of formation of the final charge-separated state (0.83 in benzonitrile) remains high, despite the large separation distance between the Fc+ and C60*- moieties. Such a high quantum yield results from efficient charge separation through the porphyrin trimer, whereas a slow charge recombination is associated with the localized porphyrin radical cation in the porphyrin trimer. The light-harvesting efficiency in the visible region has also been much improved in Fc-(ZnP)3-C60 because of exciton coupling in the porphyrin trimer as well as an increase in the number of porphyrins.
Publisher: American Chemical Society (ACS)
Date: 22-12-2015
DOI: 10.1021/ACS.LANGMUIR.5B03958
Abstract: We discovered the unique cell adhesive properties of ultraviolet (UV)-irradiated albumin films. Albumin films prepared using a cross-linking reagent with epoxy groups maintained native albumin properties, such as resistance to cell adhesion. Interestingly, the cell adhesive properties of films varied depending upon the UV irradiation time specifically, cell adhesiveness increased until 2 h of UV irradiation, when the cell number attached to the film was similar to that of culture dishes, and then cell adhesiveness decreased until 20 h of UV irradiation, after which the surface returned to the initial non-adhesive state. To elucidate the molecular mechanisms underlying this phenomenon, we examined the effect of UV irradiation on albumin film properties. The following changes occurred in response to UV irradiation: decreased α-helical structure, cleavage of albumin peptide bonds, and increased hydrophilicity and oxygen content of the albumin film surface. In addition, we found a positive correlation between the degree of cell adhesion and the amount of fibronectin adsorbed on the film. Taken together, UV-induced changes in films highly affect the amount of cell adhesion proteins adsorbed on the films depending upon the irradiation time, which determines cell adhesion behavior.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7SM00284J
Abstract: The recent growing interest in the applications of gold nanowires (AuNWs) as flexible materials has raised the fundamental issue of how their mechanical properties are related to their morphology. In this work, to address this issue, the systematic synthesis of AuNWs, their structural analysis, and their rheological investigation were demonstrated. The structural analysis of AuNWs was performed based on TEM observations and light-scattering experiments. From these observations, it was found that the length of AuNWs varies from nanometer to micrometer depending on the reaction time while a constant width of 1.6 nm is maintained. On the basis of static light-scattering experiments and a wormlike chain model, the structural parameters of AuNWs during their growth were successfully obtained. When the contour length of AuNWs reached around 5 μm, the AuNW solution showed non-Newtonian behavior and appeared to behave as a gel. Dynamic viscoelasticity measurements indicated that such viscous behavior is responsible for entanglement between AuNWs. It is concluded that AuNWs are analogous with conventional polymers in terms of both their structure and their rheological behavior.
Publisher: Elsevier BV
Date: 08-2021
Publisher: Wiley
Date: 17-06-2004
Publisher: Royal Society of Chemistry (RSC)
Date: 2012
DOI: 10.1039/C2CC31078C
Abstract: A triarylamine-functionalized terpyridine ligand formed a highly coordinated complex with europium tris(β-diketonate), which displayed reversible ''ON-OFF'' luminescence switching coupled with a ligand redox process of triarylamine/triarylaminium cations.
Publisher: American Chemical Society (ACS)
Date: 10-08-2010
DOI: 10.1016/J.JASMS.2010.08.002
Abstract: Glycosphingolipids (GSLs) are hiphilic molecules consisting of a hydrophilic carbohydrate chain and a hydrophobic ceramide moiety. They appear to be involved primarily in biological processes such as cell proliferation, differentiation, and signaling. To investigate the mechanism of brain function in more detail, a more highly sensitive method that would reveal the GSL distribution in the brain is required. In this report, we describe a simple and efficient method for mapping the distribution and localization of GSLs present in mouse brain sections using nanoparticle-assisted laser desorption/ionization imaging mass spectrometry (IMS). We have developed and tested gold nanoparticles (AuNPs) as a new matrix to maximize the detection of GSLs. A matrix of AuNPs modified with alkylamine was used to detect various GSLs, such as minor molecular species of sulfatides and gangliosides, in mouse brain sections these GSLs were hardly detected using 2,5-dihydroxybenzoic acid (DHB), which is the conventional matrix for GSLs. We achieved approximately 20 times more sensitive detection of GSLs using AuNPs compared to a DHB matrix. We believe that our new approach using AuNPs in IMS could lead to a new strategy for analyzing basic biological mechanisms and several diseases through the distribution of minor GSLs.
Publisher: The Chemical Society of Japan
Date: 05-11-2007
DOI: 10.1246/CL.2007.1348
Publisher: World Scientific Pub Co Pte Lt
Date: 12-2006
DOI: 10.1142/S1088424606000740
Abstract: The nitrogen of pyridylnaphthalenediimide ( PyNIm ) coordinates to the metal center of zinc tetraphenylporphyrin ( ZnTPP ) to form a donor-acceptor complex: ZnTPP-PyNIm . Formation of the ZnTPP-PyNIm complex was probed by UV-vis, fluorescence and NMR spectra. The fluorescence of ZnTPP is strongly quenched and the fluorescence lifetime is shortened significantly in the complex. The transient absorption spectrum of the charge-separated state ( ZnTPP •+ - PyNIm •- ) is successfully detected by laser flash photolysis measurements of the ZnTPP-PyNIm system in benzonitrile. The charge-separated state of the complex produced by the photoinduced electron transfer has the longest lifetime, (450 μs) at 288 K, ever reported for donor-acceptor systems linked covalently or non-covalently in solution. However, when benzonitrile is replaced by benzene, the triplet excited state ( 3 ZnTPP* ), rather than the charge-separated state, is formed upon laser excitation of the ZnTPP-PyNIm complex, due to the lower energy of ( 3 ZnTPP* ) compared to the charge-separated state in benzene.
Publisher: International Union of Crystallography (IUCr)
Date: 06-10-2020
DOI: 10.1107/S2056989020013146
Abstract: The title crystalline compound, [Cu 2 (NCS) 2 (C 9 H 16 N 2 ) 2 ], was obtained from the reaction of copper(I) thiocyanate (CuSCN) with ( N -prop-2-en-1-yl)piperidine-1-carbothioamide as a chelating and bridging thiourea ligand in chlorobenzene. The Cu 2 S 2 core of the dimeric molecule is situated on a crystallographic inversion centre. The copper atom is coordinated by a thiocyanate nitrogen atom, each sulfur atom of the two thiourea ligands, and the C=C double bond of the ligand in a distorted tetrahedral geometry. The dimers are linked by N—H...S hydrogen bonds, forming a network extending in two dimensions parallel to (100).
Publisher: World Scientific Pub Co Pte Lt
Date: 05-2007
DOI: 10.1142/S1088424607000412
Abstract: A supramolecular ferrocene-zinc porphyrin-pyridylnaphthalenediimide triad is formed by coordinating the pyridine entity of pyridylnaphthalenediimide with the zinc ion of a ferrocene-zinc porphyrin dyad in benzonitrile. The fluorescence of the zinc porphyrin moiety is efficiently quenched by photoinduced electron transfer from the singlet excited state of the zinc porphyrin moiety to the naphthalenediimide moiety. This is followed by subsequent electron transfer from the ferrocene moiety to the zinc porphyrin radical cation to produce the final charge-separated state, ferricenium ion-zinc porphyrin-naphthalenediimide radical anion, which is successfully detected as a transient absorption spectrum in the laser flash photolysis. The decay of the charge-separated state obeys first-order kinetics irrespective of the initial concentration of the charge-separated state to afford a long lifetime (320 μs). This is the first ex le of a supramolecular triad that has a long lifetime as compared with the charge-separated state lifetime of the component dyad.
Publisher: International Union of Crystallography (IUCr)
Date: 04-11-2016
DOI: 10.1107/S2056989016017217
Abstract: In the title compound, C 15 H 18 N 2 O 3 , the coumarin ring is essentially planar, with an r.m.s. deviation of 0.012 Å. An intramolecular O—H...N hydrogen bond forms an S (6) ring motif. The piperazine ring adopts a chair conformation. In the crystal, a C—H...O hydrogen bond generates a C (4) chain motif running along the c axis. The chain structure is stabilized by a C—H...π interaction. The chains are linked by π–π interactions [centroid–centroid distance of 3.5745 (11) Å], forming a sheet structure parallel to the bc plane.
Publisher: American Chemical Society (ACS)
Date: 07-2003
DOI: 10.1021/OL0349256
Abstract: [reaction: see text] Photoexcitation of a zinc imidazoporphyrin-fullerene dyad with a short linkage results in formation of the charge-separated state by photoinduced electron transfer. The charge-separated state has a lifetime of 310 micros in benzonitrile at 278 K, which is the longest lifetime in solution ever reported for electron donor-acceptor-linked dyads.
Publisher: The Chemical Society of Japan
Date: 09-2000
DOI: 10.1246/CL.2000.1054
Publisher: Springer Science and Business Media LLC
Date: 06-04-2010
Publisher: Royal Society of Chemistry (RSC)
Date: 2011
DOI: 10.1039/C1CC11725D
Abstract: Multiple photosynthetic reaction centres have successfully been constructed using supramolecular complexes of zinc porphyrin dendrimers [D(ZnP)(n): n = 4, 8, 16] with fulleropyrrolidine bearing a pyridine ligand (C(60)py). Efficient energy migration occurs completely between the ZnP units of dendrimers prior to the electron transfer with increasing the generation of dendrimers to attain an extremely long charge-separation lifetime.
Publisher: Elsevier BV
Date: 11-2005
Publisher: The Chemical Society of Japan
Date: 15-11-2010
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1NR07971A
Abstract: Helically aligned fused carbon hollow nanospheres on multiwalled carbon nanotubes are formed as a new form of helical structure with optical activity and chiral spaces showing chiral discrimination ability without the attachment of chiral compounds.
Publisher: Elsevier
Date: 2008
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2019
DOI: 10.1161/ATVBAHA.119.313093
Abstract: n-3 polyunsaturated fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have beneficial effects on atherosclerosis. Although specific salutary actions have been reported, the detailed distribution of n-3 polyunsaturated fatty acids in plaque and their relevance in disease progression are unclear. Our aim was to assess the pharmacodynamics of EPA and DHA and their metabolites in atherosclerotic plaques. Apolipoprotein E-deficient (Apoe −/− ) mice were fed a Western diet supplemented with EPA (1%, w/w) or DHA (1%, w/w) for 3 weeks. Imaging mass spectrometry analyses were performed in the aortic root and arch of the Apoe −/− mice to evaluate the distribution of EPA, DHA, their metabolites and the lipids containing EPA or DHA in the plaques. Liquid chromatography-mass spectrometry and histological analysis were also performed. The intima-media thickness of atherosclerotic plaque decreased in plaques containing free EPA and EPAs attached with several lipids. EPA was distributed more densely in the thin-cap plaques than in the thick-cap plaques, while DHA was more evenly distributed. In the aortic root, the distribution of total EPA level and cholesteryl esters containing EPA followed a concentration gradient from the vascular endothelium to the media. In the aortic arch, free EPA and 12-hydroxy-EPA colocalized with M2 macrophage. Administered EPA tends to be incorporated from the vascular lumen side and preferentially taken into the thin-cap plaque.
Location: Japan
No related grants have been discovered for Yukiyasu Kashiwagi.