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The effect of zephiramine on the chelate formation and extraction of some divalent metals with oxine is reported. In the presence of zephiramine, the non-extractable 1:2 zinc— and cadmium—oxine chelates as well as the extractable 1:2 nickel— and manganese—oxine chelates become highly coordinated ternary complexes, M(Q)3 (zeph), which are easily extracted into 1,2-dichloroethane. Copper is easily extracted into 1,2-dichloroethane as Cu(Q)2, which is not affected by zephiramine. 相似文献
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Noriki Kutsumura Kota Shibuya Hitoshi Yamaguchi Takao Saito 《Tetrahedron letters》2017,58(43):4099-4102
Regioselective elimination of a vicinal bis-triflate having an adjacent ether oxygen functional group has been developed. Considered in the context of our studies of the regioselective elimination of vicinal dibromide, the key to the mechanism involves the electron-withdrawing inductive effect of the neighboring oxygen functional group. Aliphatic vinyl triflate was shown to be effective in Suzuki–Miyaura cross coupling compared with corresponding aliphatic vinyl bromide. 相似文献
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We examined low-temperature synthetic route based on the amorphous nature of giant species to succeed to prepare Cs blue bronze (Cs0.3MoO3), which has never obtained by usual high-temperature methods, at ca. 680 K. Solid solutions (K1−xRbx)0.28MoO3 and (Li1−xNax)0.9Mo6O17 were also obtained at lower temperatures (ca. 670 K). For the latter system consisting of non-isostructural end members, Li0.9Mo6O17-structure type solid solution was formed even when 0.25<x<0.70, unlike the case by the usual high-temperature methods. Metastable mixed oxides Ln2Mo3O9 (Ln=La, Gd) were obtained, but not as single phases. 相似文献
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Akitami Ichihara Noriki Nio Yoshihiko Terayama Ryoji Kimura Sadao Sakamura 《Tetrahedron letters》1979,20(39):3731-3734
Various 2-alkyl-2-butenolactones were simply prepared from cyclopentadiene-maleic anhydride adducts through the retro-Diels-Alder reaction. The procedure was applied for the synthesis of dehydrolappaol A dimethyl ether. 相似文献
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Noriki Kutsumura 《Journal of carbohydrate chemistry》2013,32(5):377-385
An amino‐sugar, N‐demethylossamine, was efficiently synthesized from D‐threonine, two stereogenic centers of which were directly used as those at the C‐4 and 5 positions of the target sugar. In addition, the glycosylation study indicated that reaction of the acetate 7 with cyclopentanol under Lewis acid conditions, provided the desired α‐L‐glycoside 9α. 相似文献
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Takumi Yamauchi Takuya Takeda Masaki Yanagi Noriki Takahashi Azusa Suzuki Yoshio Saito 《Tetrahedron letters》2017,58(2):117-120
We synthesized various C2-naphthylethynylated 8-aza-7-deaza-2′-deoxyadenosines 1a–1c as novel environmentally sensitive fluorescent (ESF) purine nucleosides. In particular, the N,N-dimethylamino-substituted derivative 1c exhibits a remarkably high solvatochromicity (Δ = 111 nm). 1c-containing oligodeoxynucleotide (ODN) probes clearly discriminated an apurinic/apyrimidinic site (AP site) in the complementary strand via a change in emission wavelength and intensity when hybridized with a target ODN. 相似文献
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Setsuo Mitsuda Taro Nakajima Motoyoshi Yamano Keiichirou Takahashi Hiroe Yamazaki Kazuya Masuda Yoshiaki Kaneko Noriki Terada Karel Prokes Klaus Kiefer 《Physica B: Condensed Matter》2009,404(17):2532-2534
Magnetic oxide CuFeO2 is a magnetoelectric multiferroic with new type of spin–polarization coupling different from that in the spin-current mechanism, where magnetic field-induced or nonmagnetic impurity-induced proper helical magnetic ordering generates a spontaneous electric polarization parallel to the helical axis. Using a CuFe1−xGaxO2 sample with x=0.035, in which the single ferroelectric phase is realized below TN8 K in zero magnetic field unlike CuFe1−xAlxO2, we have performed pyroelectric current, thermally stimulated current (TSC) and polarized neutron diffraction measurements to study a memory effect that the electric polarization is partially preserved even for 2nd-cooling from above TN without poling electric field. It was found that the charge trapped during 1st-cooling with poling electric field, which is released as TSC on heating, plays an important role in the memory effect. 相似文献
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Noriki Kutsumura Shohei Toguchi Masatoshi Iijima Osamu Tanaka Izumi Iwakura Takao Saito 《Tetrahedron》2014
DBU-promoted HBr-eliminations of a variety of vicinal dibromides having an adjacent heteroatom (F, O, or N) under mild basic conditions and relevant theoretical calculations were carried out. These HBr-eliminations proceeded more or less regioselectively, and all associated calculation results agreed with the experimental facts. This work suggests that the HBr-elimination selectivity is an effect of the electronegativity of the neighboring heteroatoms themselves rather than the electron-withdrawing effects of the entire heterofunctional group. 相似文献