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111.
Kawamura K Horikiri H Hayakawa J Seki C Yoshizawa K Umeuchi H Nagase H 《Chemical & pharmaceutical bulletin》2004,52(6):670-674
Chemical syntheses of three kinds of potential metabolites of TRK-820, a potent kappa-opioid receptor agonist, were described. One of the potential metabolites 2, 17-N-dealkylated TRK-820, was synthesized starting from noroxycodone through 8 steps in 21% total yield. Glucuronidation of intermediate 10 and compound 1, the free base of TRK-820, was carried out stereoselectively to give 3-O-beta-D-glucuronides 15 and 16 in good yields, respectively. Syntheses of potential conjugated metabolites 3 and 4 were accomplished through 10 steps and 2 steps in 11% and 43% total yields, respectively. Among the potential metabolites of TRK-820, compounds 2 and 4 were identified as metabolites in human hepatocytes. The results of pharmacological studies of compounds 2, 3, and 4 are described. 相似文献
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Dr. Yuya Ashida Akihito Egi Dr. Kazuya Arashiba Prof. Dr. Hiromasa Tanaka Taichi Mitsumoto Dr. Shogo Kuriyama Prof. Dr. Kazunari Yoshizawa Prof. Dr. Yoshiaki Nishibayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(25):e202200557
A series of chromium-halide, -nitride, and -dinitrogen complexes bearing carbene- and phosphine-based PCP-type pincer ligands has been newly prepared, and some of them are found to work as effective catalysts to reduce dinitrogen under atmospheric pressure, whereby up to 11.60 equiv. of ammonia and 2.52 equiv. of hydrazine (16.6 equiv. of fixed N atom) are produced based on the chromium atom. To the best of our knowledge, this is the first successful example of chromium-catalyzed conversion of dinitrogen to ammonia and hydrazine under mild reaction conditions. 相似文献
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T. Ishikawa T. Sekiguchi K. Yoshizawa K. Naito M.L.W. Thewalt K.M. Itoh 《Solid State Communications》2010,150(37-38):1827-1830
Isoelectronic beryllium (Be) pair centers in silicon have been studied by photoluminescence spectroscopy under a magnetic field. The photoluminescence of the bound-exciton recombination at this center shows that the number of Zeeman split peaks is the smallest for the magnetic field applied along a direction. This result provides direct evidence that the Be pairs orient themselves in directions. The values of the hole and electron in this bound exciton determined by fitting of the Zeeman diagrams support the shallow acceptor character of this isoelectronic center. 相似文献
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The palladium-catalyzed hydrophenoxycarbonylation of internal alkynes by phenol and carbon monoxide was successfully realized by Pd(OAc)2/dppp catalyst system in the co-presence of Zn dust. 相似文献
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Dr. Masahiro Yamashina Sho Matsuno Dr. Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Michito Yoshizawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14147-14150
The methyl group is a small substituent, usually showing relatively weak or no interactions with other functional groups and metal ions. Herein, we present the recognition of the number of methyl groups on synthetic and natural aromatic compounds (i.e., benzene and xanthine derivatives, respectively) by the 1 nm‐sized polyaromatic cavity of a coordination capsule in water. Detailed competitive encapsulation experiments as well as X‐ray crystallographic analysis revealed that multiple guest–host CH3–polyaromatic interactions in the confined nanospace are key driving forces for the high selectivity. 相似文献
120.
Anisotropic Expansion of an M2L4 Coordination Capsule: Host Capability and Frame Rearrangement 下载免费PDF全文
Masahiro Yamashina Tsubasa Yuki Dr. Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Michito Yoshizawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4200-4204
Anisotropic expansion of a spherical M2L4 coordination capsule through the elongation of the ligand led to a new M2L′4 capsule. The expanded capsule provides an elliptical cavity encircled by polyaromatic frameworks with large openings and thereby can encapsulate elliptical fullerene C70 and monofunctionalized fullerene C60 in high yields. In addition, selective formation of a new M2L2L′2 capsule occurs by mixing the original M2L4 and expanded M2L′4 capsules in a 1:1 ratio upon addition of C60 or monofunctionalized C60 as a template molecule. 相似文献