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101.
Shindo K Kumagai G Takano M Sawada D Saito N Saito H Kakuda S Takagi K Ochiai E Horie K Takimoto-Kamimura M Ishizuka S Takenouchi K Kittaka A 《Organic letters》2011,13(11):2852-2855
C15-Substituted 1α,25-dihydroxyvitamin D(3) analogs were synthesized for the first time to investigate the effects of the modified CD-ring on biological activity concerning the agonistic positioning of helix-3 and helix-12 of the vitamin D receptor (VDR). X-ray cocrystallographic analysis proved that 0.6 ? shifts of the CD-ring and shrinking of the side chain were necessary to maintain the position of the 25-hydroxy group for proper interaction with helix-12. The 15-hydroxy-16-ene derivative showed higher binding affinity for hVDR than the natural hormone. 相似文献
102.
Akamine Y Yasui-Furukori N Kojima M Inoue Y Uno T 《Journal of separation science》2010,33(21):3292-3298
A simple and sensitive column‐switching HPLC‐UV method was developed for the simultaneous determination of aripiprazole, a novel atypical antipsychotic drug, and its active metabolite, dehydroaripiprazole in human plasma. Aripiprazole, its active metabolite and 7‐[5‐[4‐(3‐chloro‐2‐methylphenyl)‐1‐piperazinyl]pentyloxy]‐3,4‐dihydro‐2(1H)‐quinolinone (OPC‐14558) as an internal standard were extracted from 1 mL of plasma using a mixture of chloroform/n‐heptane (3:7, v/v), and the extract was injected into a column I (TSK BSA‐ODS/S precolumn, 5 μm) for cleanup and column II (C18 STR ODS‐II analytical column, 5 μm) for separation. Peaks were detected with an UV detector set at a wavelength of 254 nm, and the total time for chromatographic separation was ~20 min. Mean absolute recoveries were 74.0 and 74.7% for aripiprazole and dehydroaripiprazole, respectively. Intra‐ and inter‐day CVs were less than 7.5 and 7.1% for aripiprazole concentrations ranging from 2 to 600 ng/mL, and 9.2 and 4.5% for dehydroaripiprazole concentrations ranging from 2 to 160 ng/mL. The validated concentration ranges for this method were 1–500 ng/mL and the limits of detection were 0.5 ng/mL for both aripiprazole and dehydroaripiprazole. This method was applied to pharmacokinetic study in human volunteers and patients taking aripiprazole. 相似文献
103.
Midori A. Arai Prof. Dr. Mina Sato Keisuke Sawada Takahiro Hosoya Masami Ishibashi Prof. Dr. 《化学:亚洲杂志》2008,3(12):2056-2064
Chromones and flavonoids are important bioactive compounds. We envisioned that new heterocyclic‐substituted chromones or flavonoids might act as new bioactive compounds. To obtain diverse molecules, we developed an efficient one‐pot synthesis by Michael aldol reaction of chromone and flavonoid derivatives bearing heterocyclic units. The 2,3‐heterocyclic‐substituted chromones were obtained in one step. Moreover, the use of substituted benzaldehydes and subsequent addition of heterocyclic aldehydes gave 3‐pyridyl‐substituted flavones. We also examined these one‐pot reactions in the solid phase. To introduce an additional point of diversity into the molecules, Suzuki–Miyaura coupling was performed. Furthermore, we identified the cytotoxicity of the synthesized compounds against cancer cells (PANC1 and HeLa cells). Several compounds were cytotoxic to these cancer cells. 相似文献
104.
Kazumasa Honda Hiroshi Yamawaki Makoto Matsukawa Midori Goto Takehiro Matsunaga Katsutoshi Aoki Masatake Yoshida Shuzo Fujiwara 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):m319-m321
In the crystal structure of the title compound, [Fe(H2O)6](C6H2N3O7)2·2H2O, the centrosymmetric cationic iron complexes and picrate anions form separate stacks extending along the b axis. No picrate species ligate to the metal cation. Picrate ions are linked to one another in the stack via short intermolecular C⃛C contacts of 3.083 (4) and 3.055 (4) Å. Variable‐temperature X‐ray diffraction measurements performed between room temperature and 93 K showed a linear decrease of the lattice parameters, suggesting that there is no phase transition. 相似文献
105.
We prepared nickel oxide (NiO) thin films with p-type Cu dopants (5 at%) using a sol–gel solution process and investigated their structural, optical, and electrical characteristics by X-ray diffraction (XRD), atomic force microscopy (AFM), optical transmittance and current–voltage (I–V) characteristics. The crystallinity of the NiO films improved with the addition of Cu dopants, and the grain size increased from 38 nm (non-doped) to 50 nm (Cu-doped). The transmission of the Cu-doped NiO film decreased slightly in the visible wavelength region, and the absorption edge of the film red-shifted with the addition of the Cu dopant. Therefore, the width of the optical band gap of the Cu-doped NiO film decreased as compared to that of the non-doped NiO film. The resistivity of the Cu-doped NiO film was 23 Ω m, which was significantly less than that of the non-doped NiO film (320 Ω m). Thus, the case of Cu dopants on NiO films could be a plausible method for controlling the properties of the films. 相似文献
106.
107.
Heavy metal immobilization in aqueous solution using calcium phosphate and calcium hydrogen phosphates 总被引:1,自引:0,他引:1
Sugiyama S Ichii T Fujisawa M Kawashiro K Tomida T Shigemoto N Hayashi H 《Journal of colloid and interface science》2003,259(2):408-410
This study examines the possibilities for removing heavy metal cations from water with calcium phosphate, calcium hydrogen phosphate, and calcium dihydrogen phosphate at 293 K. It was reported that immobilization of aqueous heavy metal cations, which is known to be one of the characteristic properties of calcium hydroxyapatite, proceeded favorably with these phosphates. Calcium phosphate, calcium hydrogen phosphate, and calcium dihydrogen phosphate could favorably remove Pb2+ from aqueous solution. Calcium hydrogen phosphate also removed aqueous Cu2+, Co2+, and Cd2+, whereas these cations were not immobilized by calcium phosphate and calcium dihydrogen phosphate. A contribution of the dissolution-precipitation mechanism to immobilization with these phosphates is suggested. 相似文献
108.
109.
Reduced osteoblastic population and defective mineralization in osteopetrotic (op/op) mice 总被引:6,自引:0,他引:6
Sakagami N Amizuka N Li M Takeuchi K Hoshino M Nakamura M Nozawa-Inoue K Udagawa N Maeda T 《Micron (Oxford, England : 1993)》2005,36(7-8):688-695
Osteopetrotic (op/op) mice fail to exhibit bone remodeling because of a defective osteoclast formation due to a lack of macrophage colony-stimulating factor. In this study, we investigated the femora of op/op mice to clarify whether the osteoblastic population and bone mineralization are involved in osteoclasts or their bone resorption. The op/op mice extended the meshwork of trabecular bones from the chondro-osseous junction to the diaphyseal region. In the femoral metaphyses of op/op mice, intense alkaline phosphatase (ALPase)-positive osteoblasts were observed on the metaphyseal bone in close proximity to the erosion zone of the growth plates. Von Kossa's staining revealed scattered mineralized nodules and a fine meshwork of mineralized bone matrices while the wild-type littermates developed well-mineralized trabeculae parallel to the longitudinal axis. In contrast to the metaphysis, some op/op diaphyses showed flattened osteoblasts with weak ALPase-positivity, and the other diaphyses displayed bone surfaces without a covering by osteoblasts. It is likely, therefore, that the osteoblastic population and activity were lessened in the op/op diaphyses. Despite the osteopetrotic model, von Kossa's staining demonstrated patchy unmineralized areas in the op/op diaphyses, indicating that a lower population and/or the activity of osteoblasts resulted in defective mineralization in the bone. Transmission electron microscopy disclosed few osteoblasts on the diaphyseal bones, and instead, bone marrow cells and vascular endothelial cells were often attached to the unmineralized bone. Osteocytes were embedded in the unmineralized bone matrix. Thus, osteoclasts appear to be involved in the osteoblastic population and activity as well as subsequent bone mineralization. 相似文献
110.
Efficient Asymmetric Hydrogenation of α‐Acetamidocinnamates through a Simple,Readily Available Monodentate Chiral H‐Phosphinate 下载免费PDF全文
Dr. Xiang‐Bo Wang Dr. Midori Goto Dr. Li‐Biao Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(13):3631-3635
An air‐stable, simple (RP)‐mentylbenzylphosphinate, readily available in large quantities, can efficiently induce the rhodium‐catalyzed asymmetric hydrogenation of α‐acetamidocinnamates with high enantioselectivity (up to 99.6 % ee). Intramolecular hydrogen bonding plays an important role in this asymmetric induction. 相似文献