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171.
N Yoshinari Y Nagao A Yokoi A Igashira-Kamiyama T Konno 《Dalton transactions (Cambridge, England : 2003)》2012,41(37):11259-11262
The reactions of an S-bridged trinuclear palladium(ii) complex, [Pd(3)(d-pen-N,O,S)(3)] (d-H(2)pen = d-penicillamine), with ethylenediamine (en) and racemic (R,R/S,S) 1,2-cyclohexanediamine (chxn) in water gave mononuclear palladium(ii) complexes, [Pd(d-pen-N,S)(en)] (1) and [Pd(d-pen-N,S)(chxn)] (2), respectively. Of two diastereomers, [Pd(d-pen-N,S)(R,R-chxn)] (2(R)) and [Pd(d-pen-N,S)(S,S-chxn)] (2(S)), possible for 2, 2(S) was exclusively isolated in a high yield. 相似文献
172.
Y. Hayami H. Ichikawa A. Someya M. Aratono K. Motomura 《Colloid and polymer science》1998,276(7):595-600
The surface tension of aqueous solutions of tetradecyl-trimethylammonium chloride (TTAC) and decyltrimethylammonium chloride
(DeTAC) were measured as a function of temperature at concentrations below and above the critical micelle concentration under
atmospheric pressure. The entropy and energy of adsorption from the monomeric state and from the micellar state and also the
entropy and energy of micelle formation for TTAC were evaluated and compared with those of dodecyltrimethyl-ammonium chloride
(DTAC). The values of ΔM
W
s and ΔM
W
u for TTAC and DTAC systems show that the micelle formation is driven by the entropy at low temperatures and by the energy
at high temperatures.
Received: 9 December 1997 Accepted: 4 March 1998 相似文献
173.
Kazuyoshi Nakamura Asako Uemoto Toyoko Imae Conxita Solans Hironobu Kunieda 《Journal of colloid and interface science》1995,170(2)
The stability and size control of reverse vesicles have been investigated for a sucrose monoalkanoate/hexaethylene glycol hexadecyl ether/decane/water system. The stability is highly dependent on the surfactant mixing ratio, amount of added water, and vesicle size. The size distribution of reverse vesicles produced by simple mixing is very large, but larger vesicles can be removed by means of the extrusion method and reasonably homogeneously size-distributed reverse vesicles can be obtained. If a probe-type ultrasonicator is used, the reverse vesicles obtained are homogeneous and of very small size (50-70 nm in diameter) and they are considered to be of the unilamellar type. 相似文献
174.
Yoshinori Katsuyama Takayuki Kurokawa Tatsuo Kaneko Jian Ping Gong Yoshihito Osada Norishige Yotsukura Taizo Motomura 《Macromolecular bioscience》2002,2(4):163-169
The inhibition of germination and development of zoospores originating from Laminaria angustata originated on various kinds of hydrogels is studied. The effects of the water content of the gel (the degree of swelling), the electrical nature (neutral, positive charge, negative charge), the charge density, the counterions of hydrogels on the inhibition of zoospore germination and development of gametophytes are phenomenologically investigated. Among the gels investigated, poly(acrylic acid) (PAA) gel showed a dramatic inhibition to germination, and might serve as a novel, environmentally safe inhibitor of zoospore adhesion. 相似文献
175.
176.
Md. Chanmiya Sheikh Shunsuke Takagi Asako Ogasawara Masayuki Ohira Ryuta Miyatake Hitoshi Abe Toshiaki Yoshimura Hiroyuki Morita 《Tetrahedron》2010,66(12):2132-3975
The reaction of N-(3-phenylpropionyloxy)phthalimide (1a) and N-tosyloxy (5a,b) derivatives with nucleophiles was examined and found to give the products via Lossen-type rearrangement. In order to obtain the scope of this reaction mechanism, further studies the reaction of several N-sulfonyloxyimide derivatives with various nucleophiles under similar conditions were carried out and found to afford the corresponding same types of products in high yields. 相似文献
177.
Treatment of (NH4)[Au(D‐Hpen‐S)2](D‐H2pen = D‐penicillamine) with CoCl2·6H2O in an acetate buffer solution, followed by air oxidation, gave neutral AuICoIII and anionic AuI3CoIII2 polynuclear complexes, [Au3Co3(D‐pen‐N,O,S)6]([ 1 ]) and [Au3Co2(D‐pen‐N,S)6]3? ([ 2 ]3?), which were separated by anion‐exchange column chromatography. Complexes [ 1 ] and [ 2 ]3? each formed a single isomer, and their structures were determined by single‐crystal X‐ray crystallography. In [ 1 ], each of three [Au(D‐pen‐S)2]3?metalloligands coordinates to two CoIII ions in a bis‐tridentate‐N,O,S mode to form a cyclic AuI3CoIII3 hexanuclear structure, in which three [Co(D‐pen‐N,O,S)2]? octahedral units and six bridging S atoms adopt trans(O) geometrical and R chiral configurations, respectively. In [ 2 ]3?, each of three [Au(D‐pen‐S)2]3? metalloligands coordinates to two CoIII ions in a bis‐bidentate‐N,S mode to form a AuI3CoIII2 pentanuclear structure, in which two [Co(D‐pen‐N,S)3]3? units and six bridging S atoms adopt ∧ and R chiral configurations, respectively. 相似文献
178.
pH‐Controlled Multiple Chiral Inversion That Induces Molecular Dimerization in a Gold(I)–Cobalt(III) Coordination System with L‐Cysteinate 下载免费PDF全文
Pei‐Shan Lee Dr. Asako Igashira‐Kamiyama Dr. Naoto Kuwamura Dr. Nobuto Yoshinari Prof. Takumi Konno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(22):6646-6649
Herein, a unique coordination system that exhibits multiple chiral inversions and molecular dimerization in response to a subtle pH change is reported. Treatment of (Δ)2‐H3[Au3Co2(L ‐cys)6] (H3[ 1 a ]) with [Co3(aet)6](NO3)3 (aet=2‐aminoethanethiolate) in water at pH 7 gave a 1:1 complex salt of [Co3(aet)6]3+ and [ 1 a ]3?, retaining the AuI3CoIII2 structure and chiral configurations of [ 1 a ]3?. Similar treatment at pH 9 led to not only the inversion of all of the chiral CoIII and S centers but also the dimerization of [ 1 a ]3?, giving a 2:1 complex salt of [Co3(aet)6]3+ and (Λ)4(R)12‐[Au6Co4(L ‐cys)12]6? ([ 2 ]6?). When dissociated from [Co3(aet)6]3+ in solution, [ 2 ]6? was converted to (Λ)2(R)6‐[Au3Co2(L ‐cys)6]3? ([ 1 b ]3?) with retention of the chiral configurations. 相似文献
179.
Asako Yamayoshi Yohei Matsuyama Mikihiko Kushida Akio Kobori Akira Murakami 《Photochemistry and photobiology》2014,90(3):716-722
DNA methylation and demethylation significantly affect the deactivation and activation processes of gene expression significantly. In particular, C‐5‐methylation of cytosine in the CpG islands is important for the epigenetic modification in genes, which plays a key role in regulating gene expression. The determination of the location and frequency of DNA methylation is important for the elucidation of the mechanisms of cell differentiation and carcinogenesis. Here we designed a psoralen‐conjugated oligonucleotide (PS‐oligo) for the discrimination of 5‐methylcytosine (5‐mC) in DNA. The cross‐linking behavior of psoralen derivatives with pyrimidine bases, such as thymine, uracil and cytosine has been well discussed, but there are no reports which have examined whether cross‐linking efficiency of psoralen with cytosine would be changed with or without C‐5 methylation. We found that the cross‐linking efficiency of PS‐oligo with target‐DNA containing 5‐mC was greatly increased compared to the case of target‐DNA without 5‐mC, approximately seven‐fold higher. Here we report a new aspect of the photocross‐linking behavior of psoralen with 5‐mC that is applicable to a simple, sequence‐specific and quantitative analysis for the discrimination of 5‐mC in DNA, which can be applicable to study the epigenetic behavior of gene expressions. 相似文献
180.
Targeting Cancer with PCPA‐Drug Conjugates: LSD1 Inhibition‐Triggered Release of 4‐Hydroxytamoxifen 下载免费PDF全文
Yosuke Ota Dr. Yukihiro Itoh Asako Kaise Dr. Kiminori Ohta Prof. Yasuyuki Endo Dr. Mitsuharu Masuda Dr. Yoshihiro Sowa Prof. Toshiyuki Sakai Prof. Takayoshi Suzuki 《Angewandte Chemie (International ed. in English)》2016,55(52):16115-16118
Targeting cancer with small molecule prodrugs should help overcome problems associated with conventional cancer‐targeting methods. Herein, we focused on lysine‐specific demethylase 1 (LSD1) to trigger the controlled release of anticancer drugs in cancer cells, where LSD1 is highly expressed. Conjugates of the LSD1 inhibitor trans‐2‐phenylcyclopropylamine (PCPA) were used as novel prodrugs to selectively release anticancer drugs by LSD1 inhibition. As PCPA‐drug conjugate (PDC) prototypes, we designed PCPA‐tamoxifen conjugates 1 a and 1 b , which released 4‐hydroxytamoxifen in the presence of LSD1 in vitro. Furthermore, 1 a and 1 b inhibited the growth of breast cancer cells by the simultaneous inhibition of LSD1 and the estrogen receptor without exhibiting cytotoxicity toward normal cells. These results demonstrate that PDCs provide a useful prodrug method that may facilitate the selective release of drugs in cancer cells. 相似文献