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191.
Pramanik S Nakamura K Usui K Nakano S Saxena S Matsui J Miyoshi D Sugimoto N 《Chemical communications (Cambridge, England)》2011,47(10):2790-2792
We found that Hoogsteen base pairs were stabilized by molecular crowding and a histone H3-mimicking peptide, which was not observed for Watson-Crick base pairs. Our findings demonstrate that the type of DNA base pair is critical for the interaction between DNA and histones. 相似文献
192.
Discrimination between 5-hydroxymethylcytosine and 5-methylcytosine by a chemically designed peptide
Nomura A Sugizaki K Yanagisawa H Okamoto A 《Chemical communications (Cambridge, England)》2011,47(29):8277-8279
An artificial phosphopeptide recognized the difference between methylated and hydroxymethylated cytosines in DNA. The Sp1 zinc finger peptide substituted by phosphotyrosine effectively discriminated between 5-methylcytosine, 5-hydroxymethylcytosine ((hm)C) and unmethylated cytosine. The DNA recognition properties of the peptide differ from those of other chemicals that detect (hm)C. 相似文献
193.
Paptchikhine A Itto K Andersson PG 《Chemical communications (Cambridge, England)》2011,47(13):3989-3991
A range of 1,2,4-trisubstituted cyclohexadienes obtained from the Birch reaction were hydrogenated asymmetrically to produce synthetically valuable chiral compounds in high enantio- and diastereoselectivity. 相似文献
194.
Sakurai K Fukumoto T Noguchi K Sato N Asaka H Moriyama N Yohda M 《Organic letters》2010,12(24):5732-5735
The 3D structures of an antitumor glycosylsterol OSW-1 and its closely related congener were investigated by NMR studies and an X-ray crystallographic analysis. The disaccharide moiety was found as a structural scaffold for the formation of a hydrophobic cluster by the biologically required functionalities. 相似文献
195.
Taishiro Nakagawa Takashi Ishihara Hideaki Yoshida Takashi Yoneya Kaori Wakamatsu Toshihiko Kadoya 《Journal of separation science》2010,33(1):37-45
The aim of this study was to classify the retention time of recombinant human monoclonal antibodies (rhMAbs) in hydroxyapatite chromatography with sodium‐phosphate gradient elution according to their physicochemical properties. We analyzed 37 rhMAbs and found that (i) the structures of both the constant and variable regions affected retention time, (ii) the number of basic amino acid residues in the variable region, particularly in the heavy chain, correlated well with retention time, and (iii) this correlation was more pronounced (e.g. r2=0.87 for 18 κ IgG1 rhMAbs) when the surface accessibility of those residues are taken into account. These findings provide a useful guide for investigators and purification‐process developers working with monoclonal antibodies. 相似文献
196.
New polymer-supported phosphonate reagents have been prepared and evaluated for the synthesis of Z-α,β-unsaturated esters. High Z-selectivity was obtained using the reagent having two o-t-BuC6H4 groups. 相似文献
197.
Masakuni Tako Takeshi Teruya Yukihiro Tamaki Kaori Ohkawa 《Colloid and polymer science》2010,288(10-11):1161-1166
Synergistic gelation of dilute (0.1% total gums) mixed solutions of xanthan and galactomannan isolated from seeds of Delonix regia was investigated. Gelation occurred in a mixed solution of xanthan and galactomannan at 0.1% total gums at room temperature (25 °C). The flow curves of mixed solutions of native xanthan and galactomannan showed plastic behavior. The maximum elastic modulus was obtained when the ratio of the xanthan to galactomannan was 2:1 at room temperature (25 °C). The largest elastic modulus was observed in the mixture solution of deacetylated xanthan. However, a small elastic modulus was obtained in the mixture with depyruvated xanthan. The results obtained supported the interaction mechanism between xanthan and galactomannan (locust bean gum) previously proposed, and the pyruvate methyl groups might also take part in the interaction. 相似文献
198.
Ken-ichi Kato Kaori Ito-Akita Hiroyuki Ohno 《Journal of Solid State Electrochemistry》2000,4(3):141-145
Poly(ethylene oxide) (PEO) oligomers having alkali metal thiolate groups on the chain ends (PEO
m
-S−M+) were prepared as an ion conductive matrix. The molecular weight of the PEO part (m) and the content of the thiolate groups in the molecule were changed to analyze the effect of carrier ion concentration in
the bulk. In a series of potassium salt derivatives, PEO350-SK showed the highest ionic conductivity of 6.42 × 10−5 S/cm at 50 °C. In spite of a poor degree of dissociation which was derived from the acidity of the thiolate groups, PEO
m
-SM showed quite high ionic conductivity among other PEO/salt hybrids. PEO
m
-SM had glass transition temperatures (T
g) 20 °C lower than other PEO/salt hybrids. Lowering the T
g was concluded to be effective in providing higher ionic conductivity for PEO-based polymer electrolytes.
Received: 30 April 1999 / Accepted: 20 June 1999 相似文献
199.
Takeishi K Sugishima K Sasaki K Tanaka K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(22):5681-5688
A novel intramolecular hydroacylation of 5- and 6-alkynals leading to alpha-alkylidenecycloalkanones was accomplished by using cationic a rhodium(I)/BINAP complex. For all cyclizations described, a single (E)-olefin isomer was obtained. At elevated temperature, hydroacylation and double bond migration of 5- and 6-alkynals proceeded in a one-pot reaction to give cycloalkenones. An intramolecular hydroacylation of a 7-alkynal was unsuccessful. This method represents an attractive new route to highly functionalized alpha-alkylidenecycloalkanones and cycloalkenones. 相似文献
200.
Kaori Sugiki Yasushi Narushima Hiroshi Yabe 《Journal of Optimization Theory and Applications》2012,153(3):733-757
In this paper, we propose a three-term conjugate gradient method based on secant conditions for unconstrained optimization
problems. Specifically, we apply the idea of Dai and Liao (in Appl. Math. Optim. 43: 87–101, 2001) to the three-term conjugate gradient method proposed by Narushima et al. (in SIAM J. Optim. 21: 212–230, 2011). Moreover, we derive a special-purpose three-term conjugate gradient method for a problem, whose objective function has
a special structure, and apply it to nonlinear least squares problems. We prove the global convergence properties of the proposed
methods. Finally, some numerical results are given to show the performance of our methods. 相似文献