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961.
Toshio Ito Nobuya Tomiyoshi Koki Nakamura Shizuo Azuma Makoto Izawa Fumio Maruyama Mitsutoshi Yanagiya Haruhisa Shirahama Takeshi Matsumoto 《Tetrahedron》1984,40(1):241-255
The total synthesis of dl-coriolin has been achieved in a stereoselective way. The key tricyclic intermediate was synthesized from dicyclopentadiene through a route which involved an SN2 reaction at a neopentylic position. 相似文献
962.
Hitoshi Ito Yumi Ohki Yuhei Watanabe Hiromi Sunaga Isao Ishigaki 《Radiation Physics and Chemistry》1993,42(4-6):597-600
Relative sensitivities of endospores of Bacillus pumilus E601, B. subtilis IAM1069, B. megaterium S31 and B. brevis S5 to gamma rays, converted X rays (bremsstrahlung) and electron beams were examined in order to estimate the conditions in which converted X rays kill Bacillus spores. The radiation sensitivities to gamma rays and electron beams of each strain dried on glass fiber filter without additives were found to be almost equivalent, and D values were obtained as follows: 1.5–1.6 kGy for B. pumilus, 1.4–1.5 kGy for B. subtilis, 1.9–2.0 kGy for B. megaterium and 1.6–2.0 kGy for B. brevis. The radiation sensitivities of endospores of each strain to electron beams were slightly lower than those to gamma rays in the dry condition with additives of 2% peptone + 1 % glycerin on glass fiber filters. The increase of radiation resistance in the presence of additives was also observed with X rays, and it was on an intermediate level between those with gamma rays and electron beams. In the dry condition using cellulose filter paper, only the radiation resistances of B. megaterium and B. brevis in the presence of additives B. megaterium and B. brevis in the presence of additives were increased. 相似文献
963.
The title axially dissymmetric organosilicon compound is obtainable in optically pure from by synthesis of the racemate followed by resolution with a chiral poly(triphenylmethyl methacrylate) column. The structure has been established by spectroscopic and single crystal X-ray diffraction methods. 相似文献
964.
965.
Separation of radioactive metabolites in cultured tea cells fed with [14C]phenylalanine was conducted using high-speed counter-current chromatography. Among seven components obtained our studies focused two metabolites, i.e. (-)-epicatechin and D,L-catechin. The specific radioactivity of (-)-epicatechin was 212.01 KBq/mg, amounting to 8.5% of the total radioactivity of ethyl acetate extract while that of D,L-catechin was 1.0006 MBq/mg or 5.4% of the total. 相似文献
966.
Hojo H Matsumoto Y Nakahara Y Ito E Suzuki Y Suzuki M Suzuki A Nakahara Y 《Journal of the American Chemical Society》2005,127(39):13720-13725
Peptide thioester corresponding to a MUC2 tandem repeat unit, which retains seven GalNAc moieties, was prepared by the Fmoc method followed by the low TfOH treatment to remove benzyl groups at the carbohydrate portions. The glycosylated peptide thioester was then consecutively joined by the activation of a thioester group by silver ions to obtain a MUC2 tandem repeat model composed of 141 amino acids with 42 GalNAc moieties. 相似文献
967.
K. Sueki K. Akiyama Y. L. Zhao I. Ito Y. Ohkubo K. Kikuchi M. Katada H. Nakahara 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(1):159-164
We made systematic studies of lanthanoid metallofullerenes on the following three properties using the radiochemical method: (1) the relative production yields of metallofullerene species, (2) variation of the HPLC retention time among M(III)@C82 species, and (3) the effects of the reactor irradiation on the survival yields of each metallofullerene species. The production yields of M@C82 relative to La@C82 were found to decrease as the atomic number of M became larger and as the number of atom ratio, M/C, in the carbon rod became larger. On the other hand, the production yields of M1M2@C82, relative to that of LuM@C82 were found to increase for the larger atomic number. The retention time for the M(III)@C82 species in the Buckyprep column was found to become slightly longer for the larger atomic number but it becomes abruptly larger for Gd, and Tb by about 5%. The overall effects of the reactor irradiation on the survival yields (or retention yields) of M@C82 species were found to be (19.7±2.1)%. 相似文献
968.
Highly regioselective transformations of the acyclic α,ω-terpenediols and their diacetates to the monoacetates using lipase were accomplished. The acetylation of the α,ω-terpenediols gave regioselectively the ω-monoacetates 3, whereas the α-monoacetates 2 were obtained by hydrolysis of the α,ω-diacetates. 相似文献
969.
Using a cross-axis coil planet centrifuge, glycoproteins were separated from fermentation media of Morchella esculenta (L.) by high-speed counter-current chromatography. The performance of the apparatus was optimized with four standard proteins including pepsin, lysozyme, ovalbumin and hemoglobin and a polymer phase system composed of 12.5% (w/w) polyethylene glycol 8000 and 25% (w/w) potassium phosphate in distilled water at various pH values. Separations were performed by eluting the lower phosphate-rich phase at a flow-rate of 1.0 ml/min. Under the optimized conditions three glycoprotein components in Morchella esculenta (L.) were resolved within 6 h. 相似文献
970.
Tani K Tohda Y Takemura H Ohkita H Ito S Yamamoto M 《Chemical communications (Cambridge, England)》2001,(19):1914-1915
Syn- And anti-[3.3](3,9)carbazolophanes, which are suitable model compounds for sandwich and partial-overlap excimers, respectively, have been synthesized and characterized; the structures of both singlet and triplet carbazole excimer have been described. 相似文献