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991.
A concise total synthesis of (-)-mersicarpine from a known cyclohexanone was accomplished. The azepinoindole core was constructed by a DIBAL-H-mediated reductive ring-expansion reaction of oxime. 相似文献
992.
Three-component allylation and cyanation utilizing a ketone and an N-methoxyamine are reported. The high nucleophilicity of the N-methoxyamine and high electrophilicity of the corresponding iminium ion enable the concise synthesis of α-trisubstituted amines in a single step. 相似文献
993.
Synthesis of the indenotryptoline bisindole alkaloid, BE-54017, was accomplished using osmium-promoted cis-dihydroxylation of maleimide as a key step. After optical resolution, the absolute configuration of this molecule was determined by comparing its optical rotation and HPLC profile to those obtained for BE-54017 derived from enantiopure cladoniamide A, whose stereochemistry has been reported previously. BE-54017 with the correct absolute stereochemistry induced apoptosis of epidermal growth factor (EGF)-stimulated EGF receptor overexpressing A431 cells and inhibited vacuolar-type H(+)-ATPase (V-ATPase). 相似文献
994.
Living anionic polymerization of tert‐butyl acrylate initiated by 1,1‐diphenylhexyllithium is conducted in a flow microreactor system in the presence of lithium chloride. A high degree of control over the molecular weight distribution is achieved under easily accessible conditions, for example at ?20 °C. The subsequent reaction of a reactive polymer chain end with an alkyl methacrylate in an integrated flow micoreactor system leads to the formation of a block copolymer with a narrow molecular weight distribution.
995.
Kishi R Fujii H Kishimoto S Murata Y Ito S Okuno K Shigeta Y Nakano M 《The journal of physical chemistry. A》2012,116(17):4371-4380
We develop novel calculation and analysis methods for the dynamic first hyperpolarizabilities β [the second-order nonlinear optical (NLO) properties at the molecular level] in the second-harmonic generation based on the quantum master equation method combined with the ab initio molecular orbital (MO) configuration interaction method. As examples, we have evaluated off-resonant dynamic β values of donor (NH(2))- and/or acceptor (NO(2))-substituted benzenes using these methods, which are shown to reproduce those by the conventional summation-over-states method well. The spatial contributions of electrons to the dynamic β of these systems are also analyzed using the dynamic β density and its partition into the MO contributions. The present results demonstrate the advantage of these methods in unraveling the mechanism of dynamic NLO properties and in building the structure-dynamic NLO property relationships of real molecules. 相似文献
996.
Sugahara T Kobayashi Y Tani A Inoue T Ohgaki K 《The journal of physical chemistry. A》2012,116(10):2405-2408
To investigate the molecular interaction between guest species inside of the small and large cages of methane + propane mixed gas hydrates, thermal stabilities of the methyl radical (possibly induced in small cages) and the normal propyl and isopropyl radicals (induced in large cages) were investigated by means of electron spin resonance measurements. The increase of the total amount of the normal propyl and isopropyl radicals reveals that the methyl radical in the small cage withdraws one hydrogen atom from the propane molecule enclathrated in the adjacent large cage of the structure-II hydrate. A guest species in a hydrate cage has the ability to interact closely with the other one in the adjacent cages. The clathrate hydrate may be utilized as a possible nanoscale reaction field. 相似文献
997.
Ide Y Kagawa N Sadakane M Sano T 《Chemical communications (Cambridge, England)》2012,48(44):5521-5523
Photocatalytic mineralization of aqueous formic acid and phenol on pure TiO(2) under sunlight irradiation was substantially accelerated to give a reliable photocatalytic efficiency by conducting the reactions in the presence of a CO(2) sorbent, amine-containing SBA-15, placed in the gas phase of the reactor. 相似文献
998.
Bastakoti BP Inuoe M Yusa S Liao SH Wu KC Nakashima K Yamauchi Y 《Chemical communications (Cambridge, England)》2012,48(52):6532-6534
We report synthesis of hollow calcium phosphate (CaP) nanospheres with high surface area by using block copolymer micelles as templates. The obtained CaP nanospheres exhibit very high biocompatibility, showing great promise for intracellular bio-applications in future. 相似文献
999.
K Ino Y Kanno T Nishijo T Goto T Arai Y Takahashi H Shiku T Matsue 《Chemical communications (Cambridge, England)》2012,48(68):8505-8507
This report describes the electrochemical detection of a redox component in droplets using a local redox cycling-based electrochemical (LRC-EC) chip device consisting of 256 sensors. The time-course analyses showed that the redox compound in the droplet was dynamically changed during droplet evaporation or mass transfer through a water/oil interface. 相似文献
1000.
Jiang X Ishizumi A Suzuki N Naito M Yamauchi Y 《Chemical communications (Cambridge, England)》2012,48(4):549-551
Vertically aligned fluorescent polymer arrays with poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO) are prepared by simple drop-casting onto mesoporous alumina film. The obtained PFO arrays exhibit anisotropic photoluminescence (PL) along the orientation of the main chains. 相似文献