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131.
S. Nakajima H. Hayashi K. OHSHIMA K. Yamazaki Y. Kubo N. Samejima Y. Kakiuchi Y. Shindoh H. Koshimizu I. Sakata H. Yamauchi 《Photochemistry and photobiology》1987,46(5):783-788
Abstract Mono-DPTA-ethyleneglycol-Ga-deuteroporphyrin (MDEGD) was synthesized, by coordinating non-radioactive Ga in the porphyrin ring and connecting DTPA (diethylene-triamine-N,N,N,N,N,-pentaacetic acid) to its side chain. By labeling with 111In , chemicals for scintigraphy were developed. They were applied to Syrian golden hamsters with implanted pancreatic gland cancers and C57-black mice with Lewis lung cancer to enable tumor imaging and biodistribution examination. A comparative study was also conducted with [67 Ga]citrate. In the resultant data, [111 In]MDEGD showed larger tumor/lung, tumor/kidney and tumor/blood ratio with [67 Ga]citrate. The affinity of [n In]MDEGD in inflammatory tissue was much lower than that of 67 Ga citrate. [111 In]MDEGD lost its photosensitivity. 相似文献
132.
133.
1-(2-Pyridylamino and 2-pyrimidinylamino)naphthalene (abbreviated as Hpyn and Hpmn, respectively) and 2-(p-toluidino)quinoline (Htlq) were directly cycloaurated with Na[AuCl4] to give [AuCl2L] (L = pyn, pmn, or tlq). These complexes were characterized spectroscopically and the square planar structure of [AuCl2(pmn)] was determined by X-ray analysis. The naphthalene ring was aurated at position 2, forming a six-membered auraheterocycle with concomitant coordination of the pyrimidine-N atom. The trans influence of the carbon donor was clearly reflected in the Au–Cl bond lengths; 2.372(2) trans to C and 2.275Å trans to N. Similar square planar structures were suggested for the other two complexes. 相似文献
134.
Yuji Shinohara Tsuyoshi Nakajima Satoshi Suzuki 《Journal of Molecular Structure》1999,460(1-3):231-244
Using a semi-empirical molecular orbital method, PM3, and 2-propanol as an example, the dehydration and the dehydrogenation processes of alcohol on oxide catalysts were studied. The catalysts addressed here were four kinds of oxides (Al2O3, SiO2, ZnO, CdO) whose reaction selectivities had been experimentally determined. The usual models consisting of a surface metal ion, several oxide ions and an isopropoxy group were used in calculations. For the dehydration, heats of formation of the models were calculated at each point of the process where the distance between a β-hydrogen of the group and a basic site (i.e. oxygen of the group or a surface oxide ion) or a metal ion was gradually shortened, or where the length of the C–O bond of the group was gradually increased. A reasonable dehydration mechanism was estimated by comparing activation energies calculated from the transitions of the heats of formation. The most probable dehydrogenation mechanism was also estimated in a similar way by gradually making an -hydrogen close to a surface oxide ion, the metal ion or a surface proton. It was concluded that the dehydration proceeds by scission of the C–O bond of the group after its oxygen was attacked by some electrophile on the surface and that the dehydrogenation proceeds by a mechanism in which an -hydrogen of the group was extracted by the metal ion.
Based on the dehydration mechanism thus deduced, alkoxy groups generated by adsorption of the primary, secondary and tertiary alcohols on SiO2 were calculated in order to estimate the activation energies of their decompositions. In result, the order of the energies was found to be in good agreement with that of the decomposition rates experimentally determined by Kitahara. This agreement gives support to the validity of the mechanism deduced for the dehydration of alcohol. 相似文献
135.
H Kimata K Nakajima H Suzuki T Koide S Yamamoto T Narita 《Chemical & pharmaceutical bulletin》1991,39(12):3327-3330
To study the thrombolytic effect of tissue plasminogen activator (t-PA) on cerebral emboli, we characterized cerebral embolization in stroke-prone spontaneously hypertensive rats (SHRSPs) and Wistar Kyoto rats (WKYs). [125I]Fibrin clot particles (20-100 microns diameter) were injected twice at an interval of 90 min into the left internal carotid artery of WKYs and SHRSPs. After each injection, spontaneous embolus dissolution was monitored with a gamma-ray detector placed on the head of the embolic rats. Embolus dissolution was spontaneously generated in 15 min after the injection of fibrin clots. In WKYs, 21% and 42% of the clots were dissolved 30 and 90 min after the second embolization, respectively. On the other hand, the spontaneous embolus dissolution in SHRSPs was significantly lower than that of WKYs, indicating that the endogenous fibrinolytic ability of SHRSPs is less potent than that of normotensive rats. The intravenous administration of t-PA at doses of 75, 250 and 750 micrograms/kg caused a dose-dependent embolus dissolution in SHRSPs. Furthermore, systematically applied t-PA produced embolus dissolution without causing systemic plasminogen activation, fibrinogen breakdown or bleeding. In conclusion, the intravenous administration of t-PA produces selective embolus dissolution without systemic fibrino(geno)lysis in a cerebral embolic SHRSP. 相似文献
136.
Abstract. A photoreceptor system, “mycochrome”, is involved in a blue and near UV reversible photo-reaction which in turn plays an important role in the photocontrol of conidial development in Alternaria tomato, Botrytis cinerea and Helminthosporium oryzae. Conidial development was controlled by alternating exposures to blue and near UV light with the final response being determined by the final light received. When the final light was near UV a conidium developed; when it was blue, conidiation was inhibited and a “sterile” conidiophore was formed. The effects of the two lights were alternatively reversible. Blue and near UV reversible photoreaction was also found in a light-minus-dark difference spectrum of an intracellular particulate fraction isolated from dark-grown mycelia of A. tomato, and two pigments, PB (blue absorbing type) and PNUV (near UV absorbing type), were contained in that photoreaction. PB was tightly bound to the particulate fraction and PNUV was either soluble in the cytoplasm or very loosely bound to the particulate fraction. Blue and near UV reversible photoreaction occurred only under the coexistence of PB and PNUV. That is, a dip in the near UV region and peak absorbance in the blue region was induced by irradiation with near UV light; however, both conditions were partially dissipated with a subsequent irradiation of blue light. These absorbance changes were revers-ibly repeated by alternating doses of blue and near UV light. When molecular oxygen was introduced after exposure to near UV light, peak absorbance in the blue region rapidly disappeared, and these absorbance changes were repeatedly reversible. Similar results were obtained by treatment with sodium hydrosulfite and molecular oxygen. Thus, it was concluded that the mycochrome system suggested in photo-conidiation was consistent with certain active substances showing blue and near UV reversible absorbance changes and caused by photooxidation reduction reaction. 相似文献
137.
Takeshi SasakiHirotsugu Takizawa Kyota UhedaTakahiro Yamashita Tadashi Endo 《Journal of solid state chemistry》2002,166(1):164-170
Two new high-pressure phases of binary boron-sulfur compounds, B2S3-II and B2S3-III, were synthesized at 3-6.2 GPa. A single crystal of B2S3-III was grown and the structure was determined (tetragonal, space group I41/a, a=16.086(2) Å, c=30.488(4) Å; V=7888(1) Å3, Z=100, R=3.0% and Rw=2.8% for 3047 observed data [I>3.00σ(I)]. The structure of B2S3-III consists of two kinds of macrotetrahedra built up from 20 and 34 BS4-tetrahedra. These macrotetrahedra connect each other to form an interpenetrating zincblende-type structure by sharing BS4-tetrahedra at the corners of those. B2S3-III is anticipated having a rather disordered structure. From the UV-Vis diffuse reflectance spectrum, the optical band gap of B2S3-III was estimated to be 3.7 eV. 相似文献
138.
Stereocontrolled alkynylzirconation of unactivated alkynes was achieved by the reaction of an alkyne with Cp2ZrEt2 and alkynyl halide in this order. After hydrolysis of the alkynylzirconation product, trisubstituted enyne derivatives were obtained in good yields. Functionalized enynes were also prepared by the reaction of the alkynylzirconation products with a variety of electrophiles. Subsequent addition of the second alkynyl halide to the alkynylzirconation products provided an in situ protocol for bisalkynylation of alkynes into (Z)-enediynes in good yields. 相似文献
139.
Okada T Yamanaka K Hirose Y Goto Y Tani T Inagaki S 《Physical chemistry chemical physics : PCCP》2011,13(17):7961-7967
The excited state characteristics of phenylene (Ph)-bridged periodic mesoporous organosilica (PMO) powders with crystal-like and amorphous wall structures are investigated. Crystal-like Ph-PMO has a molecular ordering of the bridging organic moieties with intervals of 0.76 and 0.44 nm parallel and perpendicular to the mesochannel direction, respectively, whereas amorphous Ph-PMO has no molecular-level periodicity in the wall. Fluorescence from the exciton and excimer of the Ph moieties and the defect center in the silicate network were detected at room temperature, but fluorescence from the excimer and the defect center were not detected at 77 K for crystal-like Ph-PMO dispersed in a methanol/ethanol mixed solvent. The decay curve of the exciton fluorescence of crystal-like Ph-PMO at room temperature was analyzed successfully using a one-dimensional diffusion model quenched by the defect center and the excimer site. The results were discussed in comparison with those for the crystal-like biphenylene-bridged PMO reported in the preceding paper (Yamanaka et al., Phys. Chem. Chem. Phys., 2010, 12, 11688-11696). The existence of excited states with various conformations including ground state dimers or aggregates of the Ph moieties was suggested for amorphous Ph-PMO. It was clearly apparent that the differences in the excited state dynamics reflected the differences in the molecular-level structure in the wall. 相似文献
140.
Tutorial review: to achieve molecule-based spintronic devices, an organic conducting magnet that exhibits both conductivity and magnetism in a cooperative manner must be constructed. As a building block for such new materials, a spin-polarized donor radical, which serves as a molecular "spin-filter" in its singly oxidized state, was designed and synthesized. The resistivity of ion radical salts of selenium-substituted, tetrathiafulvalene-based spin-polarized donor radicals decreased substantially in the presence of a magnetic field, thus indicating cooperative conductivity and magnetism. 相似文献