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1.
D3h‐Symmetric Porphyrin‐Based Rigid Macrocyclic Ligands for Multicofacial Multinuclear Complexes in a One‐Nanometer‐Sized Cavity 下载免费PDF全文
Yohei Ohkoda Akane Asaishi Tomoya Namiki Tomoaki Hashimoto Midori Yamada Koichiro Shirai Yuta Katagami Dr. Tomoaki Sugaya Prof. Makoto Tadokoro Prof. Akiharu Satake 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(33):11745-11756
The one‐step synthesis of D3h‐symmetric cyclic porphyrin trimers 1 composed of three 2,2′‐[4,4′‐bis(methoxycarbonyl)]bipyridyl moieties and three porphyrinatozinc moieties was achieved from a nickel‐mediated reductive coupling of meso‐5,15‐bis(6‐chloro‐4‐methoxycarbonylpyrid‐2‐yl)porphyrinatozinc. Although cyclic trimers 1 were obtained as a mixture that included other cyclic and acyclic porphyrin oligomers, an extremely specific separation was observed only for cyclic trimers 1 when using columns of silica gel modified with pyrenylethyl, cyanopropyl, and other groups. Structural analysis of cyclic trimers 1 was carried out by means of NMR spectroscopy and X‐ray crystallography. Treatment of an η3‐allylpalladium complex with a cyclic trimer gave a tris(palladium) complex containing three η3‐allylpalladium groups inside the space, which indicated that the bipyridyl moieties inside the ring could work as bidentate metalloligands. 相似文献
2.
Midori Kobayashi Hitoshi Awoki Yoshimi Nakazaki Gisaku Nakamura 《Graphs and Combinatorics》1989,5(1):243-244
In this paper, a perfect one-factorization ofK
36 is given, which is factor-1-rotational. 相似文献
3.
In the presence of CuCN, reaction of γ,γ-dialkoxyallylic zirconium species 1 with imines proceeded at the γ-position of 1 to give gem-dialkoxyhomoallylic amines 3 in high yield. In this reaction, γ,γ-dialkoxyallylic zirconium species 1 acts as an α,β-unsaturated acyl anion equivalent. 相似文献
4.
Yoko M. NAKAO Takashi MIYAWAKI Shinji YASUNO Kazuhiro NAKAO Sachiko TANAKA Midori IDA Masakazu HIRATA Masato KASAHARA Kiminori HOSODA Kenji UESHIMA Kazuwa NAKAO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2012,88(8):454-461
Objective: To investigate the significance of intra-abdominal fat area (IAFA) on new onset of individual components of the metabolic syndrome: high blood pressure, dyslipidemia, or hyperglycemia. Methods: We conducted a longitudinal study using checkup data of a hospital from 1994 to 2010. Of 25,255 subjects, we examined 1,380 Japanese, who underwent computed tomography to measure IAFA and had no metabolic syndrome components at baseline. Results: During 3.6 years of the mean follow-up period, one of metabolic syndrome components occurred in 752 subjects. Of three components, high blood pressure was more prevalent. The multiple Cox regression analysis disclosed that IAFA is significantly associated with onset of metabolic syndrome components (HR: 1.05 per 10 cm2, 95%CI: 1.03–1.07). This finding was independent of BMI, and significant even in non-obese individuals with body mass index <25 kg/m2. Conclusions: MERLOT study demonstrates that IAFA is an independent predictor for new onset of individual components of the metabolic syndrome, even in non-obese healthy Japanese. 相似文献
5.
Rinta Sato Dr. Kosuke Suzuki Midori Sugawa Prof. Dr. Noritaka Mizuno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(39):12982-12990
Polyoxometalates (POMs) with heterodinuclear lanthanoid cores, TBA8H4[{Ln(μ2‐OH)2Ln′}(γ‐SiW10O36)2] ( LnLn′ ; Ln=Gd, Dy; Ln′=Eu, Yb, Lu; TBA=tetra‐n‐butylammonium), were successfully synthesized through the stepwise incorporation of two types of lanthanoid cations into the vacant sites of lacunary [γ‐SiW10O36]8? units without the use of templating cations. The incorporation of a Ln3+ ion into the vacant site between two [γ‐SiW10O36]8? units afforded mononuclear Ln3+‐containing sandwich‐type POMs with vacant sites ( Ln1 ; TBA8H5[{Ln(H2O)4}(γ‐SiW10O36)2]; Ln=Dy, Gd, La). The vacant sites in Ln1 were surrounded by coordinating W? O and Ln? O oxygen atoms. On the addition of one equivalent of [Ln′(acac)3] to solutions of Dy1 or Gd1 in 1,2‐dichloroethane (DCE), heterodinuclear lanthanoid cores with bis(μ2‐OH) bridging ligands, [Dy(μ2‐OH)2Ln′]4+, were selectively synthesized ( LnLn′ ; Ln=Dy, Gd; Ln′=Eu, Yb, Lu). On the other hand, La1 , which contained the largest lanthanoid cation, could not accommodate a second Ln′3+ ion. DyLn′ showed single‐molecule magnet behavior and their energy barriers for magnetization reversal (ΔE/kB) could be manipulated by adjusting the coordination geometry and anisotropy of the Dy3+ ion by tuning the adjacent Ln′3+ ion in the heterodinuclear [Dy(μ2‐OH)2Ln′]4+ cores. The energy barriers increased in the order: DyLu (ΔE/kB=48 K)< DyYb (53 K)< DyDy (66 K)< DyEu (73 K), with an increase in the ionic radii of Ln′3+; DyEu showed the highest energy barrier. 相似文献
6.
Jonatas de Oliveira S. Silva Prof. Mércia V. S. Sant'Anna Dr. Ava Gevaerd MSc. Jéssica B. S. Lima MSc. Michael D. S. Monteiro Dr. Sanny W. M. M. Carvalho Dr. Eliana Midori Sussuchi 《Electroanalysis》2021,33(10):2152-2160
This study introduces modified carbon paste electrodes with carbon nitride nanosheets (CNNS) and outlines their application for the determination of hydroxychloroquine sulfate (HCQ) in tablets and synthetic urine samples. CNNS were synthesized by hydrothermal route (200 °C, 10 h) using melamine and citric acid as their precursors. The carbon nitride nanosheets-based electrode (CNNS/E) presented a linear dynamic range for HCQ (LDR), ranging from 10.0 nmol l−1 to 6.92 μmol l−1, and detection (LOD) and quantification limits (LOQ) of 0.16 nmol l−1 and 0.52 nmol l−1, respectively. LOD and LOQ were calculated by the equations: LOD=3(Sd/b), and LOQ=10(Sd/b). The modified sensor presented excellent relative standard deviations for parameters such as repeatability (2.39 % and 1.87 %) and reproducibility (3.22 % and 2.32 %) in HCQ oxidation peaks (1 and 2). The CNNS/E has not shown significant variations in its anodic signal intensity in the presence of some organic and inorganic substances. It is worth bearing in mind that CNNS/E can be easily manufactured and the sensor has the lowest HCQ detection limits reported so far. The proposed sensor was successfully applied for HCQ determination in tablets and synthetic urine, showing good recovery values and an error of 0.60 % about comparative method in tablet samples, assuring the quality of the method. 相似文献
7.
Midori Ishihara 《Tetrahedron》2007,63(6):1474-1480
Aldehydes were converted to the corresponding 2-imidazolines and 2-oxazolines in good yields by the reaction with ethylenediamine and aminoethanol, respectively, using molecular iodine and potassium carbonate. Moreover, primary alcohols were directly converted to the corresponding 2-imidazolines and 2-oxazolines via aldehydes in one-pot manner with ethylenediamine and aminoethanol, respectively, using molecular iodine and potassium carbonate. 相似文献
8.
O-Glycosylations using thiomethyl glycosides as donors were compared under both frozen and unfrozen conditions. In the presence of MeOTf as a promoter, enormous rate acceleration was observed when the glycosylation was conducted in p-xylene below its freezing point. 相似文献
9.
Yutaka Maeda Prof. Akiko Sagara Masahiro Hashimoto Yuya Hirashima Katsuya Sode Tadashi Hasegawa Prof. Makoto Kanda Midori O. Ishitsuka Dr. Takahiro Tsuchiya Dr. Takeshi Akasaka Prof. Toshiya Okazaki Prof. Hiromichi Kataura Prof. Jing Lu Prof. Shigeru Nagase Prof. Seiji Takeuchi 《Chemphyschem》2009,10(6):926-930
Reversible and non‐bonding interaction between SWNTs and ODCB is observed from the analyses of visible near‐infrared absorption data and Raman spectroscopies (see spectra). The solvent effect on SWNTs effectively controls the electronic structure of SWNTs under homogeneous conditions.
10.
Hironao Nakayama Masako Nakahara Erina Matsugi Midori Soda Tomoka Hattori Koki Hara Ayuki Usami Chiaki Kusumoto Shigeki Higashiyama Kiyoyuki Kitaichi 《Molecules (Basel, Switzerland)》2021,26(1)
Ferulic Acid (FA) is a highly abundant phenolic phytochemical which is present in plant tissues. FA has biological effects on physiological and pathological processes due to its anti-apoptotic and anti-oxidative properties, however, the detailed mechanism(s) of function is poorly understood. We have identified FA as a molecule that inhibits apoptosis induced by hydrogen peroxide (H2O2) or actinomycin D (ActD) in rat pheochromocytoma, PC12 cell. We also found that FA reduces H2O2-induced reactive oxygen species (ROS) production in PC12 cell, thereby acting as an anti-oxidant. Then, we analyzed FA-mediated signaling responses in rat pheochromocytoma, PC12 cells using antibody arrays for phosphokinase and apoptosis related proteins. This FA signaling pathway in PC12 cells includes inactivation of pro-apoptotic proteins, SMAC/Diablo and Bad. In addition, FA attenuates the cell injury by H2O2 through the inhibition of phosphorylation of the extracellular signal-regulated kinase (ERK). Importantly, we find that FA restores expression levels of brain-derived neurotrophic factor (BDNF), a key neuroprotective effector, in H2O2-treated PC12 cells. As a possible mechanism, FA increases BDNF by regulating microRNA-10b expression following H2O2 stimulation. Taken together, FA has broad biological effects as a neuroprotective modulator to regulate the expression of phosphokinases, apoptosis-related proteins and microRNAs against oxidative stress in PC12 cells. 相似文献