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161.
162.
Fullerene cyclopentadienide (PhCH(2))(2)Ph(3)C(60)(-) and indenide (PhCH(2))(2)PhC(60)(-), each bearing two different organic groups, were efficiently synthesized through regioselective reactions of 1,4-(PhCH(2))(2)C(60) with an organocopper reagent (PhMgBr/CuBr.SMe(2)) or a Grignard reagent (PhMgBr) followed by deprotonation with KO(t)()Bu. 相似文献
163.
A direct preparative route to benzoyltrimethylsilane has been found by the reaction of benzoyl chloride with hexamethyldisilane in the presence of a specified palladium(II) complex as catalyst. 相似文献
164.
The pharmacokinetic study of 67Ga-citrate (67Ga) following intravenous (i.v.), subcutaneous (s.c.) and intraperitoneal (i.p.) injection was performed in anesthetized rats using the repeated blood sampling method by cannulation technique into the external jugular vein. The disappearance of 67Ga from the blood following i.v. and s.c. injection was best fit a three-exponential equation. There was no significant difference between the areas under the curves following i.v. and s.c. injection of 67Ga. In the case of i.p. injection, the disappearance of 67Ga from the blood was described by a two-exponential equation. However, the maximum blood radioactivity was very low, and the disappearance rate of 67Ga from the blood was extremely slow compared to the other routes of injection. The conclusion from these results was that s.c. injection was as suitable as i.v. injection, but i.p. injection was not appropriate for the distribution study of 67Ga such as scintigraphy or autoradiography. However, i.p. route may be available for a special experiment which needs the long-time retention of 67Ga in the blood. 相似文献
165.
Tetsuo Suami Hiroaki Sasai Kazuhiro Matsuno Nobuo Suzuki Yoshimasa Fukuda Osamu Sakanaka 《Tetrahedron letters》1984,25(40):4533-4536
Tunicamycins and their eight analogs have been synthesized by condensation of a N-acetyl-D-glucosamine derivative and an anomeric chloride of tunicaminyl uracil, followed by deprotections and N-acylation. 相似文献
166.
Selective flow-injection determination of methanol in the presence of ethanol based on a multi-enzyme system with chemiluminescence detection 总被引:2,自引:0,他引:2
Yoshiie Sekine
Masayasu Suzuki
Toshifumi Takeuchi Eiichi Tamiya Isao Karube 《Analytica chimica acta》1993,280(2):179-184A highly selective flow-injection system was developed for the determination of methanol. The system consisted of three immobilized enzymes with luminol chemiluminescence detection. First, methanol was oxidized in the presence of alcohol oxidase to yield formaldehyde and hydrogen peroxide. The hydrogen peroxide produced was then destroyed by catalase. The formaldehyde formed in the first stage was further oxidized by NAD+-formaldehyde dehydrogenase. The NADH formed was oxidized by 1-methoxy-5-methylphenazinium methylsulphate (1-MPMS), and finally the reduced 1-MPMS was spontaneously oxidized and hydrogen peroxide was produced. The concentration of the hydrogen peroxide produced, which was proportional to the initial concentration of methanol, was determined by luminol chemiluminescence. The determination range was from 0.1 to 100 mg l−1 and the response time was less than 2 min per sample with a relative standard deviation of less than 3%. The system showed good selectivity for methanol; the response was ca. 50 times higher than for ethanol. 相似文献
167.
A unique family of 1,3,8,10-tetrahydro-2,9-diazadibenzo[cd,lm]perylenes (THDAP) was prepared through a new synthetic strategy. Completion of the synthesis was achieved in several steps from commercially available perylene-3,4,9,10-tetracarboxylic dianhydride via reactions between 3,4,9,10-tetra(chloromethyl)perylene and primary amines. The successful use of a variety of primary amines in the reactions indicated that the synthetic approach provides a rich opportunity to produce new functionalized perylene derivatives. 相似文献
168.
169.
Production of micron-sized monodispersed composite polymer particles by seeded polymerization utilizing the dynamic swelling method 总被引:1,自引:0,他引:1
In order to develop the seeded polymerization technique utilizing the dynamic swelling method (DSM) proposed by authors for
the production of micron-sized mono-dispersed “composite” polymer particles consisting of two kinds of polymers, the seeded
polymerization for the dispersion of ethyl methacry-late (EMA)-swollen PS particles prepared utilizing DSM was carried out.
Monodispersed PS/poly(ethyl methacrylate) (PEMA) composite particles having 7 μm in diameter were produced by the addition
of NaCl to lower the solubility of EMA in medium and by the addition of CuCl2 as a water-soluble inhibitor to depress the by-production of submicron-sized PEMA particles.
Received: 16 July 1996 Accepted: 10 October 1996 相似文献
170.
Nagao S Hirai Y Suzuki A Yamamoto Y 《Journal of the American Chemical Society》2005,127(12):4146-4147
A 19F NMR study on the acid-alkaline transition in sperm whale myoglobin reconstituted with a perfluoromethyl heme, 13,17-bis(2-carboxylatoethyl)-3,8-diethyl-2,12,18-trimethyl-7-trifluoromethylporphyrinatoiron(III), demonstrated that the thermodynamics of the transition is predominantly controlled by the stability of acidic form. 相似文献