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101.
Manabu KuroboshiTomotake Yano Shogo KamenoueHiromu Kawakubo Hideo Tanaka 《Tetrahedron》2011,67(32):5825-5831
Electroreduction of triphenylphosphine dichloride in acetonitrile was performed successfully in an undivided cell fitted with an aluminium sacrificial anode and a platinum cathode, wherein Al3+, which was electrogenerated at the anode would react as a Lewis acid with triphenylphosphine dichloride to afford tetra-coordinate chlorotriphenylphosphonium species and subsequent two-electron reduction at the cathode would give triphenylphosphine. One-pot transformation of triphenylphosphine oxide to triphenylphosphine was achieved successfully by the treatment of triphenylphosphine oxide with oxalyl chloride and subsequent electroreduction. In a similar manner, some tetra-coordinate triphenylphosphonium species derived from triphenylphosphine oxide were reduced electrochemically to triphenylphosphine in moderate yields. 相似文献
102.
Masayori Hagimori Fumiko Hara Naoko Mizuyama Takeshi Fujino Hideo Saji Takahiro Mukai 《Molecules (Basel, Switzerland)》2022,27(4)
Zinc is an essential trace element involved in many biological activities; however, its functions are not fully understood. To elucidate the role of endogenous labile Zn2+, we developed a novel ratiometric fluorescence probe, 5-(4-methoxyphenyl)-4-(methylsulfanyl)-[2,2′-bipyridin]-6-amine (6 (rBpyZ)) based on the 6-amino-2,2′-bipyridine scaffold, which acts as both the chelating agent for Zn2+ and the fluorescent moiety. The methoxy group acted as an electron donor, enabling the intramolecular charge transfer state of 6 (rBpyZ), and a ratiometric fluorescence response consisting of a decrease at the emission wavelength of 438 nm and a corresponding increase at the emission wavelength of 465 nm was observed. The ratiometric probe 6 (rBpyZ) exhibited a nanomolar-level dissociation constant (Kd = 0.77 nM), a large Stokes shift (139 nm), and an excellent detection limit (0.10 nM) under physiological conditions. Moreover, fluorescence imaging using A549 human lung adenocarcinoma cells revealed that 6 (rBpyZ) had good cell membrane permeability and could clearly visualize endogenous labile Zn2+. These results suggest that the ratiometric fluorescence probe 6 (rBpyZ) has considerable potential as a valuable tool for understanding the role of Zn2+ in living systems. 相似文献
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108.
Kato N Sakayanagi M Nakayama T Nishimura H Ogamo A 《Journal of chromatography. A》2002,973(1-2):159-166
A novel detection method for 21 different anions by thin-layer chromatography is presented. Anions on the target plate form salts with amine in a developing solvent and are visualized after staining with citric acid-acetic anhydride reagent as white spots contrasting against a pale red-pink background. This method has particularly high sensitivity for anions of chlorate, sulfate, phosphate, chromate and dichromate (0.02-0.05 microg). The method is demonstrated to efficiently detect toxic arsenite in curry sauce as an example application. The proposed method offers highly efficient indirect detection for a wide range of anions, and serves as a purification procedure for the preparation of anionic sample solutions for other analytical methods. 相似文献
109.
Shinozuka K Matsumoto N Suzuki H Moriguchi T Sawai H 《Chemical communications (Cambridge, England)》2002,(22):2712-2713
A chimeric oligoDNA composed of a natural beta-anomeric oligonucleotide portion and an unnatural alpha-anomeric oligonucleotide portion forms an alternate stranded triplex possessing enhanced thermal stability compared to the triplexes composed of the parental oligomers. 相似文献
110.
Liquid crystal induced circular dichroism (LCICD) measurements were made to investigate the pretransitional phenomena in the SA phase just above the SA-S*C and SA-S*CA phase transitions of both the first and the second order. The pretransitional LCICD in SA was observed in the second order phase transition to S*c and S*cA, suggesting the existence of a dynamic helical structure in SA. Such behaviour disappears when the transition is of the first order. It seems that the handedness of the dynamic helix in SA is the same as that in S*c even when the lower temperature phase is S*cA. This is explained as a result of a dominant contribution of ferroelectric soft mode. 相似文献