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Mamoru Tanaka,
Hiromi Kataoka,
Motoshi Mabuchi,
Shiho Sakuma,
Satoru Takahashi,
Ryoto Tujii, Haruo Akashi,
Hiromi Ohi,
Shigenobu Yano,
Akimichi Morita,
Takashi Joh
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ABSTRACT: Background/Aim: Photodynamic therapy (PDT) is an attractive, minimally invasive modality for cancer therapy that utilizes the interaction of light and photosensitizer. To improve the efficacy of PDT, development of cancer specificity of the photosensitizer is needed. Cancer cells consume more glucose than normal cells. In this study, the efficacy of PDT using a newly developed photosensitizer, glycoconjugated chlorin (H2TFPC-SGlc), was compared with Talaporfin, which is clinically used in Japan.
Photosensitizers were administered to gastric and colon cancer cell lines, followed by irradiation of light, and the cell death-inducing effects were compared. Xenograft tumor mouse models were established and photosensitizer accumulation was assessed and antitumor effects analyzed.
In vitro, H(2)TFPC-SGlc was 30 times more cytotoxic to cancer cells than was Talaporfin. In vivo, H(2)TFPC-SGlc accumulation was higher in xenograft tumors and significantly suppressed tumor growth when compared with Talaporfin.
This novel glycoconjugated chlorin is potentially useful in PDT.
Anticancer research 03/2011; 31(3):763-9. · 1.73 Impact Factor
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ABSTRACT: The structure of the title compound, [Mo(2)(C(4)H(8)NO(2)S)(2)O(2)S(2)], has been redetermined. Besides obvious differences between the original [Drew & Kay (1971 ▶). J. Chem. Soc. A, pp. 1851-1854] and the current unit-cell parameters, some packing features of the structure are also different; these findings are the result of significant improvements in the precision and accuracy of the present structure analysis. The two Mo atoms in the dimeric complex have very similar distorted trigonal-bipyramidal environments. Each Mo atom is bonded to an S atom and to an N atom of an l-cysteine ester ligand, to a terminal O atom and to two S atoms which bridge to the adjacent Mo atom [Mo⋯Mo separation = 2.8191 (2) Å]. N-H⋯O(carbon-yl) and N-H⋯O(terminal) hydrogen-bonding inter-actions consolidate the crystal packing. During the synthesis, the originally employed l-cysteinate ligand has been converted to the l-cysteinate methyl ester ligand. Since this reaction does not take place without tin(IV) chloride, it is clear that tin(IV) chloride acts as a catalyst for the reaction.
Acta Crystallographica Section E Structure Reports Online 01/2010; 66(Pt 5):m573. · 0.35 Impact Factor
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ABSTRACT: A new water-insoluble Fe(3+)-TCAS[4]/TMPyP complex linked tetraanionic Fe(III)-thiacalix[4]arenetetrasulfonate (Fe(3+)-TCAS[4]) with tetracationic tetrakis(1-methylpyridinium-4-yl)porphine (TMPyP) via ionic interaction was prepared. The peroxidase-like catalytic activity of the Fe(3+)-TCAS[4]/TMPyP complex was investigated based on the dye formation reaction by oxidation of 4-aminoantipyrine and phenol with H(2)O(2) catalyzed by peroxidase. This Fe(3+)-TCAS[4]/TMPyP complex showed the highest activity in pH 5.5 acetate buffer solutions, and it was applied to the photometric determination of trace amounts of H(2)O(2). The calibration curve was linear over the range from 1.0 to 35 microg of H(2)O(2) in a 1.0 ml sample solution. Moreover, the method using glucoseoxidase and the Fe(3+)-TCAS[4]/TMPyP complex was applied to the determination of glucose, and the results were satisfactory even in control sera. The Fe(3+)-TCAS[4]/TMPyP complex can be applied to a practical sample, such as blood or urine, as an analytical reagent for the photometric determination of H(2)O(2) in place of peroxidase.
Chemical & pharmaceutical bulletin 12/2009; 57(12):1400-4. · 1.70 Impact Factor
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ABSTRACT: The title and the chemical names of the paper by Tabuchi, Takahashi, Gotoh, Akashi & Ishida [Acta Cryst. (2005), E61, o4215-o4217] are corrected.[This corrects the article DOI: 10.1107/S160053680801948X.].
Acta Crystallographica Section E Structure Reports Online 01/2009; 65(Pt 3):e11. · 0.35 Impact Factor
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ABSTRACT: Heterodinuclear [(Ni (II)L)Ln (III)(hfac) 2(EtOH)] (H 3L = 1,1,1-tris[(salicylideneamino)methyl]ethane; Ln = Eu, Gd, Tb, and Dy; hfac = hexafluoroacetylacetonate) complexes ( 1.Ln) were prepared by treating [Ni(H 1.5L)]Cl 0.5 ( 1) with [Ln(hfac) 3(H 2O) 2] and triethylamine in ethanol (1:1:1). All 1.Ln complexes ( 1.Eu, 1.Gd, 1.Tb, and 1.Dy) crystallized in the triclinic space group P1 (No. 2) with Z = 2 with very similar structures. Each complex is a face-sharing dinuclear molecule. The Ni (II) ion is coordinated by the L (3-) ligand in a N 3O 3 coordination sphere, and the three phenolate oxygen atoms coordinate to an Ln (III) ion as bridging atoms. The Ln (III) ion is eight-coordinate, with four oxygen atoms of two hfac (-)'s, three phenolate oxygen atoms of L (3-), and one ethanol oxygen atom coordinated. Temperature-dependent magnetic susceptibility and field-dependent magnetization measurements showed a ferromagnetic interaction between Ni (II) and Gd (III) in 1.Gd. The Ni (II)-Ln (III) magnetic interactions in 1.Eu, 1.Tb, and 1.Dy were evaluated by comparing their magnetic susceptibilities with those of the isostructural Zn (II)-Ln (III) complexes, [(ZnL)Ln(hfac) 2(EtOH)] ( 2.Ln) containing a diamagnetic Zn (II) ion. A ferromagnetic interaction was indicated in 1.Tb and 1.Dy, while the interaction between Ni (II) and Eu (III) was negligible in 1.Eu. The magnetic behaviors of 1.Dy and 2.Dy were analyzed theoretically to give insight into the sublevel structures of the Dy (III) ion and its coupling with Ni (II). Frequency dependence in the ac susceptibility signals was observed in 1.Dy.
Inorganic Chemistry 08/2008; 47(13):5736-45. · 4.60 Impact Factor
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ABSTRACT: Four anthracene and four acetylene units are used to construct a chiral pi-conjugate macrocycle, the chirality of which is due to the restricted rotation about acetylenic axes. Enantiomers were readily resolved by chiral HPLC and racemized slowly even at 70 degrees C.
Organic Letters 03/2008; 10(3):417-20. · 5.86 Impact Factor
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ABSTRACT: In the crystal structure of the title compound, [Co(H(2)O)(6)](2)(C(24)H(12)O(16)S(8))·H(2)O, the thia-calix[4]arenetetra-sulfonate (= TCAS(4-)) anions adopt a cone-type conformation with an additional water mol-ecule as a guest mol-ecule in the hydro-phobic cavity. The TCAS(4-) anions are arranged in layers in an up-down fashion. These anionic layers alternate with cationic layers consisting of rather regular octahedral cations (symmetry m). Several medium O-H⋯O hydrogen-bond inter-actions exist between the aqua ligands of the [Co(H(2)O)(6)](2+) cations and the O atoms of the sulfonate groups. In addition to the two crystallographically different Co atoms, two S and four O atoms are situated on mirror planes.
Acta Crystallographica Section E Structure Reports Online 01/2008; 64(Pt 6):m797-8. · 0.35 Impact Factor
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ABSTRACT: The reaction of [Mo3S4(H2O)9]4+ (1) with hydrotris(pyrazolyl)borate (Tp) ligands produced [Mo3S4Tp3]Cl x 4 H2O ([3]Cl x 4 H2O) in an excellent yield. An X-ray structure analysis of [3]Cl x 4 H2O revealed that each molybdenum atom bonded to the Tp ligand. We report four salts of 3, [3]Cl x 4 H2O, [3]tof x 2 H2O, [3]PF6 x H2O, and [3]BF4 x 2 H2O in this paper. The solubility and stability of the chloride salt in organic solvents differ completely from those of the other salts. We have also prepared a new compound, [Mo3OS3Tp3]PF6 x H2O ([4]PF6 x H2O), via the reaction of [Mo3OS3(H2O)9]4+ (2) with KTp in the presence of NH4PF6. All the molybdenum atoms bonded to Tp ligand. 1H NMR signals corresponding to nine protons bonded to three pyrazole rings in one Tp were observed in a spectrum (at 253 K) of [3]BF4 x 2 H2O. It shows that cluster 3 has a 3-fold rotation axis in CD2Cl2 solution. Twenty-one 1H NMR signals corresponding to twenty-seven protons bonded to nine pyrazole rings in three Tp ligands were observed in a spectrum (at 233 K) of [4]PF6 x H2O; obviously, 4 has no 3-fold rotation axis, in contrast to 3. The short CH...mu3S distance caused large upfield chemical shifts in the 1H NMR spectra of 3 and 4. The reaction of 3 with metallic iron in CH2Cl2 produced [Mo3FeS4XTp3] (X = Cl (5), Br (6)). X-ray structure analysis of 5 has revealed the existence of a cubane-type core Mo3FeS4. Complex 3 functions as a metal-complex ligand for preparing a novel mixed-metal complex even in nonaqueous solvents. The cyclic voltammogram of 5 shows two reversible one-electron couples (E(1/2) = -1.40 and 0.52 V vs SCE) and two irreversible one-electron oxidation processes (E(pc) = 1.54 and 1.66 V vs SCE).
Inorganic Chemistry 08/2006; 45(14):5429-37. · 4.60 Impact Factor
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ABSTRACT: The reaction of [Mo(3)S(4)(H(2)O)(9)](4+) (1) with [(CpRhCl(2))(2)] afforded a novel rhodium-molybdenum cluster, [{Mo(3)RhCpS(4)(H(2)O)(7)(O)}(2)](8+) (2). X-ray structure analysis of [2](pts)(8).14H(2)O (pts(-) = CH(3)C(6)H(4)SO(3)(-)) has revealed the existence of a new oxo-bridged twin cubane-type core, (Mo(3)RhCpS(4))(2)(O)(2). The high affinity of the CpRh group for sulfur atoms in 1 seems to be the main driving force for this reaction. The strong Lewis acidity of the CpRh group in intermediate A, [Mo(3)RhCpS(4)(H(2)O)(9)](6+), caused a release of proton from one of the water molecules attached to the molybdenum atoms to give intermediate B, [Mo(3)RhCpS(4)(H(2)O)(8)(OH)](5+). The elimination of two water molecules from two intermediate B molecules, followed by the deprotonation reaction of hydroxo bridges, generated the twin cubane-type cluster 2. The formal oxidation states of rhodium and molybdenum atoms are the same before and after the reaction (i.e., Mo(IV)(3), Rh(III)). The Mo-O-Mo moieties in [2](pts)(8).14H(2)O are nearly linear with a bond angle of 164.3(3) degrees, and the basicity of the bridging oxygen atoms seems to be weak. For this reason, protonation at the bridging oxygen atoms does not occur even in a strongly acidic aqueous solution. The binding energy values of Mo 3d(5/2), Rh 3d(5/2), and C 1s obtained from X-ray photoelectron spectroscopy measurements for [2](pts)(8).14H(2)O are 229.8, 309.3, and 285 eV, respectively. The XPS measurements on the Rh 3d(5/2) binding energy indicate that the oxidation state of Rh is 3+. The binding energy of Mo 3d(5/2) (229.8 eV) compares with that observed for [1](pts)(4).7H(2)O (230.7 eV, Mo 3d(5/2)). A lower energy shift (0.9 eV) is observed in the binding energy of Mo 3d(5/2) for [2](pts)(8).14H(2)O. This energy shift may correspond to the coordination of an oxygen atom having a negative charge to the molybdenum atom.
Inorganic Chemistry 06/2005; 44(10):3494-8. · 4.60 Impact Factor
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Yukinari Sunatsuki,
Hiromi Ohta,
Masaaki Kojima,
Yuichi Ikuta,
Yoshiyuki Goto,
Naohide Matsumoto,
Seiichiro Iijima, Haruo Akashi,
Sumio Kaizaki,
Françoise Dahan,
Jean-Pierre Tuchagues
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ABSTRACT: The [Fe(II)(H(3)L)](BF(4))(2).3H(2)O (1) complex was synthesized, where H(3)L (tris[[2-[(imidazole-4-yl)methylidene]amino]ethyl]amine) is a tripodal ligand obtained by condensation of tris(2-aminoethyl)amine and 4-formylimidazole (fim) in a 1:3 molar ratio. Starting from 1, a series of complexes, [Fe(II)(H(1.5)L)](BF(4))(0.5) (2) (=[Fe(II)(H(3)L)][Fe(II)(L)]BF(4)), [Fe(H(1.5)L)]BF(4) (3) (=[Fe(II)(H(3)L)][Fe(III)(L)](BF(4))(2)), [Fe(III)(H(3)L)](BF(4))(3).fim.H(2)O (4), and [Fe(III)(L)].2.5H(2)O (5), has been synthesized and characterized. The single-crystal X-ray structure of each complex has been determined. The Fe(II) compound, 2, and a mixed valence Fe(II)-Fe(III) compound, 3, involve formally hemi-deprotonated ligands, H(1.5)L. The structure of 3 consists of a homochiral two-dimensional assembled sheet, arising from the intermolecular hydrogen bonds between [Fe(II)(H(3)L)](2+) and [Fe(III)(L)](0) (3). All but 5 exhibit spin crossover between low-spin (LS) and high-spin (HS) states. This is a rare case where both Fe(II) and Fe(III) complexes containing the same ligand exhibit spin-crossover behavior. Magnetic susceptibility and Mössbauer studies showed that 3 has three accessible electronic states: LS Fe(II)-LS Fe(III), HS Fe(II)-LS Fe(III), and HS Fe(II)-HS Fe(III). Compounds 1-3 show the light-induced excited spin-state trapping effect at the Fe(II) sites upon irradiation with green light. The solution magnetic properties, electronic spectra, and electrochemical properties of 1, 4, and 5 were also studied.
Inorganic Chemistry 08/2004; 43(14):4154-71. · 4.60 Impact Factor
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ABSTRACT: Dinuclear [(NiL)Gd(hfac)(2)(EtOH)](H(3)L = 1,1,1-tris(N-salicylideneaminomethyl)ethane, Hhfac = hexafluoroacetylacetone), trinuclear [(NiL)(2)Gd(NO(3))], and tetranuclear [(NiL)Gd(CH(3)CO(2))(2)(MeOH)](2) complexes, were prepared by treating [Ni(HL)] with [Gd(hfac)(3)(H(2)O)(2)], Gd(NO(3))(3).6H(2)O, and Gd(CH(3)CO(2))(3).4H(2)O, respectively, in the presence of Et(3)N. All the complexes show that ferromagnetic interactions occur between the Ni(II) and Gd(III) ions.
Chemical Communications 06/2004; · 6.17 Impact Factor
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ABSTRACT: Crystal structure of zwitterionic trimethylammoniopropane sulfonate (Z1-Methyl) was determined by single-crystal X-ray diffractometry. Z1-Methyl crystallized in the monoclinic system, space group P2(1), with a = 6.3639(2), b = 10.9237(4), c = 8.1505(4) A, beta = 111.078(2) degrees, V = 528.69(4) A3, Z = 2. An inter-molecular ionic association was observed in the crystal. The shortest distance between the methyl protons of the trimethylammonium group and the oxygens of the sulfonate group was 2.51(2) A.
Analytical Sciences 06/2003; 19(5):805-6. · 1.25 Impact Factor
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ABSTRACT: Reaction of [(3-C4H7)2Rh(CH3CN)2]PF6(3-C4H7 = -methallyl) with [n-Bu4N](VO3) gives a new 3-allyl cluster [n-Bu4N]2[{(3-C4H7)2Rh}2 (V4O12)] (I) which is readily converted into a diene cluster, [n-Bu4N]2 [{(4-C8H14)Rh}2(V4O12)] (II) (C8H14=2,5-dimethyl-1,5-hexadiene) by reacting with CO or P(OEt)3;I andII have been characterized crystallographically.
Journal of Cluster Science 11/1991; 2(4):291-296. · 0.92 Impact Factor
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ABSTRACT: Magnetic susceptibilities of the tetranuclear cluster complexes [Mo3FeS4(H2O)10](CH3C6H4SO3)4·7H2O (1) and [Mo3NiS4(H2O)10](CH3C6H4SO3)4·7H2O (2) containing molybdenum ions of the 4d transition metals and the Fe or Ni ion of the 3d transition metals are measured at temperatures from ∼2 to 270 K. The magnetic susceptibilities are analyzed on the basis of the vector model formalism of Kambe. We used the models containing four metal ions Mo3(IV,III,III) and Fe(II), and Mo3(IV,III,III) and Ni(II), respectively. The exchange integrals are estimated as J1(Mo–Mo)/kB=−25 K and J2(Mo–Fe)/kB=−75 K for 1, and J1(Mo–Mo)/kB=−35 K and J2(Mo–Ni)/kB=−60 K (A(Mo)=1.1, k(Mo)=60%, A(Ni)=1.2, k(Ni)=100%; A is the parameter for orbital-angular momentum, k is an orbital reduction factor) for 2. These parameters are in excellent agreement with the experimental data of the magnetic susceptibilities of both cluster complexes.
Inorganica Chimica Acta.
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ABSTRACT: Reaction of the cubane-type cluster [Mo3CuS4(H2O10]4+ (4) with concentrated aqueous ammonia afforded a novel twin-cubane-type cluster [{(NH3)6(H2O)(OH)Mo3CuS4(O)}2]Cl4·8H2O (2). X-ray structure analysis of 2 revealed that two cubane-type Mo3CuS4 cores were bridged by two oxygen atoms. The cores are related to each other by a center of symmetry. X-ray photoelectron spectroscopy measurement of the Cu bonding energy (934.0 cV) indicates that the oxidation state of copper atom is + 1. On the basis of these results, the formal oxidation state Mo3(IV,IV,IV) is ascribed to each of the cubane-type Mo3CuS4 moieties.
Inorganica Chimica Acta. 282(1):50-54.
