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101.
RhI‐Catalyzed Intramolecular Carbonylative C−H/C−I Coupling of 2‐Iodobiphenyls Using Furfural as a Carbonyl Source 下载免费PDF全文
Takuma Furusawa Prof. Dr. Tsumoru Morimoto Dr. Yasuhiro Nishiyama Dr. Hiroki Tanimoto Prof. Dr. Kiyomi Kakiuchi 《化学:亚洲杂志》2016,11(16):2312-2315
Synthesis of fluoren‐9‐ones by a Rh‐catalyzed intramolecular C?H/C?I carbonylative coupling of 2‐iodobiphenyls using furfural as a carbonyl source is presented. The findings indicate that the rate‐determining step is not a C?H bond cleavage but, rather, the oxidative addition of the C?I bond to a RhI center. 相似文献
102.
Ade Arsianti Hiroki Tanimoto Tsumoru Morimoto Anton Bahtiar Tatsuo Takeya Kiyomi Kakiuchi 《Tetrahedron》2012,68(13):2884-2891
A novel polyhydroxylated 18-membered analogue of antimycin A3 was synthesized. Our synthesis commenced with Boc-l-threonine and was achieved by way of one-pot homocoupling/ring-closing olefin metathesis reaction cascade and Sharpless asymmetric dihydroxylation. The analogue exhibited a greater anticancer activity against HeLa cells, breast MDA-MB-231 cells, and prostate PC-3 cells compared to the original antimycin A3. 相似文献
103.
Heta Y Kumaki K Hifumi H Citterio D Tanimoto A Suzuki K 《Photochemistry and photobiology》2012,88(4):876-883
Novel photochromic amphipathic molecules, KMR‐AZn (Gd‐DTPA‐AZCn), composed of hydrophilic Gd‐DTPA and hydrophobic alkylated azobenzene were prepared. In aqueous environment, KMR‐AZn indicated self‐assembly. The resulting aggregates were demonstrated to be able to include a hydrophobic drug substitute (hydrophobic fluorescent dye) into the internal core, and to release the included compound upon photoirradiation within 10 min through the influence of azobenzene photoisomerization. This micellar MRI contrast agent exhibited three‐ to four‐fold higher r1 relaxivity (r1 = 14.5–16.5 mm ?1 s?1, 0.47 T at 40°C) than the widely applied small molecule contrast agent Gd‐DTPA (Magnevist®r1 = 4.1 mm ?1 s?1, 0.47 T at 40°C). This dual functionality of encapsulated compound release and increased MR imaging contrast indicates that KMR‐AZn is a potential candidate for application as a lipid‐based MRI‐traceable drug carrier. 相似文献
104.
Hiroki Tanimoto 《Tetrahedron letters》2007,48(36):6267-6270
The stereoselective total synthesis of (+)-galanthamine (+)-1 starting from d-glucose is described. The cyclohexene ring in (+)-1 was prepared in an optically active form from d-glucose using Ferrier’s carbocyclization reaction, and the critical quaternary carbon was stereoselectively generated via chirality transfer based on the Claisen rearrangement of a cyclohexenol. The dibenzofuran skeleton was effectively constructed by the bromonium ion-mediated intramolecular cyclization of a cyclohexene possessing a phenolic ether function. After the introduction of a carbon-carbon double bond, the Pictet-Spengler type cyclization, followed by the reduction of the amide function completed the chiral synthesis of (+)-1. 相似文献
105.
106.
R. B. Morgunov E. V. Kurganova Y. Tanimoto A. S. Markosyan A. V. Kazakova N. D. Kushch É. B. Yagubskiĭ A. D. Dubrovskiĭ G. V. Shilov 《Physics of the Solid State》2007,49(5):905-911
The magnetic properties of new radical cation salts (BEDT-TTF)2[CuMn(dca)4] (I) and (BEDT-TTF)2[Mn(dca)3] (II) [where BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene and dca = N(CN2)] are investigated using superconducting quantum interference device (SQUID) magnetometry and electron paramagnetic resonance (EPR) spectroscopy. It is established that, at temperatures below 25 K, both salts are characterized by antiferromagnetic deviations from the paramagnetic behavior. The Weiss constants for compounds I and II are determined to be ?5 and ?10 K, respectively. The corresponding correlations in the structure of compound I are short-range correlations and do not lead to a change in the effective spin equal to 5/2. It is found that the widths of the EPR lines attributed to the BEDT-TTF conducting sublattice correlate with the widths of the EPR lines associated with the magnetic sublattice of the Mn(dca) 3 ? counterion in the structure of salt II. This correlation suggests that the antiferromagnetic ordering in the magnetic sublattice of compound II affects the spin-lattice relaxation in the BEDT-TTF sublattice. The dependence of the magnetic moment on the magnetic field for compound II at a temperature of 2 K is typical of weakly frustrated uniaxial antiferromagnets and exhibits a kink in a magnetic field of 20 kOe, which corresponds to spin-flop transitions. 相似文献
107.
Ryuji Tanimoto 《Journal of Pure and Applied Algebra》2008,212(10):2284-2297
Let R be a PID. This article gives an algorithm for computing the kernel of a locally finite iterative higher derivation of a finitely generated R-domain. 相似文献
108.
Kanki A Tamada T Higaki A Noda Y Tanimoto D Sato T Higashi H Ito K 《Magnetic resonance imaging》2012,30(3):356-360
The aim was to clarify whether enhancement effects of the liver parenchyma in the hepatobiliary phase (HP) of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MR imaging were correlated with the morphological grading of the severity in cirrhosis. A total of 62 patients with chronic hepatitis or cirrhosis underwent Gd-EOB-DTPA-enhanced MR imaging. Relative enhancement (RE) of liver parenchyma was calculated from signal intensity (SI) measurements obtained at precontrast images (SIpre) and 20-min postcontrast HP images (SIpost) as: (SIpost-SIpre)/SIpre. Morphological MR grades of severity in cirrhosis were divided into four groups. Then, RE of liver parenchyma and morphologic MR grading were correlated. Regarding the morphologic severity of cirrhosis, the numbers of patients with MR grade 1, 2, 3 and 4 were 14 (23%), 7 (11%), 28 (45%) and 13 (21%), respectively. The mean REs of liver parenchyma in each group of MR morphologic grade 1, 2, 3 and 4 were 0.71±0.21, 0.62±0.16, 0.70±0.22 and 0.77±0.18, respectively. There was no significant correlation between the MR grading of morphologic severity and the RE of liver parenchyma at 20-min HP. Hepatic parenchymal enhancement in the HP of Gd-EOB-DTPA-enhanced MR imaging did not necessarily decrease according to the severity of morphologic changes in cirrhosis. This fact may suggest that the hepatic uptake of Gd-EOB-DTPA depends on the preserved hepatocytes function rather than the severity of morphologic changes in cirrhosis. 相似文献
109.
110.
Sarri G Singh DK Davies JR Fiuza F Lancaster KL Clark EL Hassan S Jiang J Kageiwa N Lopes N Rehman A Russo C Scott RH Tanimoto T Najmudin Z Tanaka KA Tatarakis M Borghesi M Norreys PA 《Physical review letters》2010,105(17):175007
The expansion of electromagnetic postsolitons emerging from the interaction of a 30 ps, 3×101? W?cm?2 laser pulse with an underdense deuterium plasma has been observed up to 100 ps after the pulse propagation, when large numbers of postsolitons were seen to remain in the plasma. The temporal evolution of the postsolitons has been accurately characterized with a high spatial and temporal resolution. The observed expansion is compared to analytical models and three-dimensional particle-in-cell results, revealing a polarization dependence of the postsoliton dynamics. 相似文献