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21.
22.
Yokokita Takuya Yano Shinya Komori Yukiko Haba Hiromitsu 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):1127-1134
Journal of Radioanalytical and Nuclear Chemistry - To investigate sulfate complex formation of Rf, we performed batch-wise ion-exchange experiments of its homologues Zr and Hf and its pseudo... 相似文献
23.
Folding of Synthetic Homogeneous Glycoproteins in the Presence of a Glycoprotein Folding Sensor Enzyme 下载免费PDF全文
Dr. Simone Dedola Dr. Masayuki Izumi Dr. Yutaka Makimura Dr. Akira Seko Dr. Akiko Kanamori Dr. Masafumi Sakono Prof. Dr. Yukishige Ito Prof. Dr. Yasuhiro Kajihara 《Angewandte Chemie (International ed. in English)》2014,53(11):2883-2887
UDP‐glucose:glycoprotein glucosyltransferase (UGGT) plays a key role in recognizing folded and misfolded glycoproteins in the glycoprotein quality control system of the endoplasmic reticulum. UGGT detects misfolded glycoproteins and re‐glucosylates them as a tag for misfolded glycoproteins. A flexible model to reproduce in vitro folding of a glycoprotein in the presence of UGGT in a mixture containing correctly folded, folding intermediates, and misfolded glycoproteins is described. The data demonstrates that UGGT can re‐glucosylate all intermediates in the in vitro folding experiments, thus indicating that UGGT inspects not only final folded products, but also the glycoprotein folding intermediates. 相似文献
24.
Development of a New Benzylating Reagent Spontaneously Releasing Benzyl Cation Equivalents at Room Temperature 下载免费PDF全文
Dr. Kohei Yamada Yuichi Tsukada Yukiko Karuo Dr. Masanori Kitamura Prof. Dr. Munetaka Kunishima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(38):12274-12278
A new O‐benzylating reagent, that is, 4‐(4,6‐diphenoxy‐1,3,5‐triazin‐2‐yl)‐4‐benzylmorpholinium trifluoromethanesulfonate (DPT‐BM), has been developed. Benzyl cation equivalents are generated from DPT‐BM by dissolving the compound in a solvent at room temperature under non‐acidic conditions. The benzylation of various alcohols by using a combination of DPT‐BM and magnesium oxide provided the benzyl ethers in good yields. 相似文献
25.
Yukiko Moriizumi Hajime Fukuda Seiya Tanaka Daisuke Tanaka Kazukiyo Nagai 《Journal of polymer science. Part A, Polymer chemistry》2020,58(18):2586-2602
This study aimed to determine the solubility and temperature dependence of methanol and ethanol vapor caused by the difference in the substituents of polyhedral oligomeric silsesquioxane (POSS)-containing polymethacrylate membranes and the spacer length between the backbone and POSS backbone. Vapor sorption of methanol and ethanol was measured at 25°C, 35°C, and 45°C for three kinds of POSS-containing polymer membranes, namely, poly(methacryl isobutyl POSS), poly(methacrylate isobutyl POSS), and poly(methacryl phenyl POSS). The primary structures of the three POSS-containing polymer chains were columnar. The solubility of alcohol vapor on the POSS-containing polymer membranes followed the mechanism of solid adsorption and not the general dissolution diffusion. The sorption amount at all three temperatures was related to the surface area of the cylindrical primary structure and the solid adsorption property of the alcohol molecule of the POSS substituent. The sorption amount increased because of the large surface area and adsorption property of alcohol molecules. Although a typical glassy polymer shows exothermic mixing and a rubbery polymer displays endothermic mixing, the sample with the POSS substituent of isobutyl group exhibited an unusual behavior of endothermic mixing despite being a glassy polymer. 相似文献
26.
Yukiko Kamiya Fuminori Sato Keiji Murayama Atsuji Kodama Susumu Uchiyama Hiroyuki Asanuma 《化学:亚洲杂志》2020,15(8):1266-1271
Serinol nucleic acid (SNA) is a promising candidate for nucleic acid‐based molecular probes and drugs due to its high affinity for RNA. Our previous work revealed that incorporation of 2,6‐diaminpurine (D), which can form three hydrogen bonds with uracil, into SNA increases the melting temperature of SNA‐RNA duplexes. However, D incorporation into short self‐complementary regions of SNA promoted self‐dimerization and hindered hybridization with RNA. Here we synthesized a SNA monomer of 2‐thiouracil (sU), which was expected to inhibit base pairing with D by steric hindrance between sulfur and the amino group. To prepare the SNA containing D and sU in high yield, we customized the protecting groups on D and sU monomers that can be readily deprotected under acidic conditions. Incorporation of D and sU into SNA facilitated stable duplex formation with target RNA by suppressing the self‐hybridization of SNA and increasing the stability of the heteroduplex of SNA and its complementary RNA. Our results have important implications for the development of SNA‐based probes and nucleic acid drugs. 相似文献
27.
Masayuki Tomiya Takeshi Fukushima Tadahiro Ogaya Yukiko Sone Shogo Mitsuhashi Toshimasa Toyo'oka 《Biomedical chromatography : BMC》2010,24(6):569-573
The levels of kynurenic acid, an endogenous antagonist of α7 nicotinic acetylcholine and N‐methyl‐D ‐aspartate receptors, were measured in microdialysis samples obtained from the prefrontal cortices of rats using column‐switching high‐performance liquid chromatography with fluorescence detection. When the perfusate was constantly infused at a rate of 1.0 μ/min, the in vitro recovery of kynurenic acid through the dialysis membrane was approximately 20.4%, and the precision was within 1.31%. Endogenous kynurenic acid in the microdialysis sample was clearly detected using column‐switching high‐performance liquid chromatography. As an application study, N‐acetyl‐L ‐aspartic acid, an endogenous metabolite and precursor of N‐acetyl‐L ‐aspartyl‐L ‐glutamic acid, which is an agonist of metabotropic glutamate receptors, was infused for 120 min through the microdialysis probe. The kynurenic acid level significantly increased during the infusion of N‐acetyl‐L ‐aspartic acid, suggesting that kynurenic acid might have some association with N‐acetyl‐L ‐aspartic acid in vivo. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
28.
29.
Nine new secoiridoid glucosides from Jasminum nudiflorum 总被引:2,自引:0,他引:2
Takenaka Y Tanahashi T Taguchi H Nagakura N Nish T 《Chemical & pharmaceutical bulletin》2002,50(3):384-389
Phytochemical study of the leaves of Jasminum nudiflorum has led to the isolation of nine new secoiridoid glucosides, jasnudiflosides F-L (1-7), nudifloside D (8) and isooleoacteoside (9). The structures of these compounds were elucidated on the basis of chemical and spectroscopic evidence. 相似文献
30.
Shimizu Y Shiokawa N Yamamoto N Kozuma M Kuga T Deng L Hagley EW 《Physical review letters》2002,89(23):233001
Propagation of a light pulse through a high-Q optical microcavity containing a few cold atoms (N<10) in its cavity mode is investigated experimentally. With less than ten cold rubidium atoms launched into an optical microcavity, up to 170 ns propagation lead time ("superluminal"), and 440 ns propagation delay time (subluminal) are observed. Comparison of the experimental data with numerical simulations as well as future experiments are discussed. 相似文献