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961.
962.
Preferential 5‐Methylcytosine Oxidation in the Linker Region of Reconstituted Positioned Nucleosomes by Tet1 Protein
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Seiichiro Kizaki Tingting Zou Dr. Yue Li Dr. Yong‐Woon Han Dr. Yuki Suzuki Prof. Dr. Yoshie Harada Prof. Dr. Hiroshi Sugiyama 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16598-16601
Tet (ten–eleven translocation) family proteins oxidize 5‐methylcytosine (mC) to 5‐hydroxymethylcytosine (hmC), 5‐formylcytosine (fC), and 5‐carboxycytosine (caC), and are suggested to be involved in the active DNA demethylation pathway. In this study, we reconstituted positioned mononucleosomes using CpG‐methylated 382 bp DNA containing the Widom 601 sequence and recombinant histone octamer, and subjected the nucleosome to treatment with Tet1 protein. The sites of oxidized methylcytosine were identified by bisulfite sequencing. We found that, for the oxidation reaction, Tet1 protein prefers mCs located in the linker region of the nucleosome compared with those located in the core region. 相似文献
963.
Anisotropic Expansion of an M2L4 Coordination Capsule: Host Capability and Frame Rearrangement
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Masahiro Yamashina Tsubasa Yuki Dr. Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Michito Yoshizawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4200-4204
Anisotropic expansion of a spherical M2L4 coordination capsule through the elongation of the ligand led to a new M2L′4 capsule. The expanded capsule provides an elliptical cavity encircled by polyaromatic frameworks with large openings and thereby can encapsulate elliptical fullerene C70 and monofunctionalized fullerene C60 in high yields. In addition, selective formation of a new M2L2L′2 capsule occurs by mixing the original M2L4 and expanded M2L′4 capsules in a 1:1 ratio upon addition of C60 or monofunctionalized C60 as a template molecule. 相似文献
964.
Hideki Tomita Christoph Mattolat Sebastian Raeder Seiji Sasada Yuki Higuchi Kunisuke Takezawa Takayoshi Muramatsu Tetsuo Iguchi Klaus Wendt 《Hyperfine Interactions》2010,196(1-3):169-176
Stable isotope analysis using Laser Ablation Assisted Resonant Ionization Mass Spectrometry (LA-RIMS) is discussed. For the case of the 87Sr/86Sr isotope ratio measurements with a single color two-photon excitation scheme, the mass discrimination effects, which occur in LA-RIMS, are analyzed and a precision of 0.6% was extracted. For preparation of LA-RIMS on Hf isotopes, a novel two-color resonant excitation scheme with subsequent non-resonant ionization has been established using a high repetition-rate Ti:Sapphire laser system. 相似文献
965.
966.
Thin film capacitors with a thickness of 200 nm were prepared on SrTiO3 (1 0 0), (1 1 0) and (1 1 1) single crystal substrates at a temperature of 973 K by pulsed laser deposition (PLD) using a KrF excimer laser in an O2-O3 atmosphere with a gas pressure of 1 Pa using an X7R sintered target. As a result, perovskite BaTiO3 solid solution films were obtained. In the X7R thin films on (1 0 0) and (1 1 0) SrTiO3, only diffraction peaks with strong intensities from BaTiO3 (1 0 0) and (1 1 0), respectively, were observed. X7R films on SrTiO3 (1 1 1) were grown epitaxially oriented to the crystal plane direction of the substrate by inserting an initial homoepitaxial SrTiO3 layer with a thickness of 4 nm. The X7R/SrTiO3 film capacitors yielded a large volumetric efficiency of 50 μF/mm3 and a temperature coefficient of capacitance (TCC) of −1.3% to 1.3% which satisfies the EIA standard specifications for X7R. 相似文献
967.
Seunghee Jung Yuki TsukudaRie Kawashima Takumi IshikiAyaka Matsumoto Aya NakaniwaMiho Takagi Takuya NoguchiNobuyuki Imai 《Tetrahedron letters》2013
Acetaminophen analogues containing α-amino acid and fatty acids were easily synthesized in 77–99% yields from the corresponding mixed carbonic carboxylic anhydrides of α-amino acid and fatty acids using aniline derivatives in aqueous MeCN. 相似文献
968.
Harada T Hiraoka Y Kusukawa T Marutani Y Matsui S Nakatsugawa M Kanda K 《Organic letters》2003,5(26):5059-5062
Bis-BINOLs 7a-c in which two BINOL units are tethered by phenylenebis(ethynyl) groups react with titanium tetraisopropoxide (2 equiv) to form intramolecular dimeric titanium(IV) aggregates 2a-c. Of these, 2a,b with an o-phenylenebis(ethynyl) tether are stable in the presence of excess titanium tetraisopropoxide. Complex 2a exhibits a relatively high enantioselectivity in asymmetric addition of diethylzinc to an aldehyde. [structure: see text] 相似文献
969.
Yamashita M Ohta N Shimizu T Matsumoto K Matsuura Y Kawasaki I Tanaka T Maezaki N Ohta S 《The Journal of organic chemistry》2003,68(4):1216-1224
The first total synthesis of (+/-)-Linderol A, a hexahydrodibenzofuran constituent of Lindera umbellata bark, with potent inhibitory activity on the melanin biosynthesis of cultured B-16 melanoma cells, was achieved through 19 steps of reaction in 6.6% overall yield, in which the critical step was a tandem reaction of a 3-ethoxycarbonylcoumarin derivative with dimethylsulfoxonium methylide to yield the 2-ethoxycarbonylcyclopenta[b]benzofuran-3-ol derivative. 相似文献
970.
The main object of this paper is the mean square I
h
(s) of higher derivatives of Hurwitz zeta functions (s, ). We shall prove asymptotic formulas for I
h
(1/2 + it) as t + with the coefficients in closed expressions (Theorem 1). We also prove a certain explicit formula for I
h
(1/2 + it) (Theorem 2), in which the coefficients are, in a sense, not explicit. However, one merit of this formula is that it contains sufficient information for obtaining the complete asymptotic expansion for I
h
(1/2 + it) when h is small. Another merit is that Theorem 1 can be strengthened with the aid of Theorem 2 (see Theorem 3). The fundamental method for the proofs is Atkinson's dissection argument applied to the product (u, )(v, ) with the independent complex variables u and v. 相似文献