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101.
Yoshio Hamashima Sadao Yamamoto Tadatoshi Kubota Katsuya Tokura Koji Ishikura Kyogi Minami Fumihiko Matsubara Masaaki Yamaguchi Ikuo Kikkawa Wataru Nagata 《Tetrahedron letters》1979,20(51):4947-4950
Synthesis of optically active 3′-nor-type 1-oxacephems from 6-APA was described. -Nitrobenzyl 7β-amino-3-chloro-7α-methoxy-1-oxa-3-cephem-4-carboxylate was also prepared. 相似文献
102.
Reaction of the laterally lithiated (S)-4-isopropyl-2-(2-methoxy-6-methylphenyl)oxazoline with p-tolualdehyde gave an inseparable mixture of the addition products in low diastereoselectivity. However, the (S,S)-product cyclized to the corresponding 3,4-dihydroisocoumarin faster than the (S,R)-product on silica gel, which allowed to be produced both enantiomers of 8-methoxy-3-(p-tolyl)-3,4-dihydroisocoumarin in moderate to good optical purity [S-enantiomer: 75% ee; R-enantiomer: 96% ee]. This procedure was applied to the short-step synthesis of optically active 3,4-dihydroisocoumarin natural products such as (R)-8-hydroxy-3-(1-tridecyl)-3,4-dihydroisocoumarin and (R)-phyllodulcin. 相似文献
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105.
The complexes with long alkyl chains {[Fe(C16-trz)3](ClO4)2}n (1), [Fe(C15-BPT)2(NCS)2] (2), [Fe(C16-salen)Cl] (3), [Fe(C16-salmmen)Cl] (4), K[Fe(C16-salen)(CN)2] (5), K[Fe(C16-salmmen)(CN)2] (6), Na[Fe(C16-salmmen)(CN)2] (7), [Mn(C16-salen)Cl] (8), [Ni(C16-salen)] (9), [Cu(C16-salen)] (10) were synthesized (C16-trz = 4-hexadecyl-1,2,4-triazole, C15-BPT = N-(3,5-di-2-pyridinyl-4H-1,2,4-triazol-4-yl)-hexadecanecarboxamide, C16-salen = N,N-bis[4-(hexadecyloxy)salicylidene]ethylenediamine, C16-salmmen = N,N′-bis[4-(hexadecyloxy)salicylidene]-1,2-diaminopropane). Langmuir–Blodgett (LB) films of compounds 1–10 were prepared (Scheme 1). The transfers of the molecules from onto the gas–water surface to glass substrate were confirmed by UV–Vis spectra. The second harmonic generation (SHG) were estimated for the LB films formed by the metal complexes. The SHG was observed for the complexes with the long alkyl chains in LB film. The order of the intensity for the SHG related with the number of unpaired d electrons or the d electron configurations. 相似文献
106.
Katsuya Ikegami Masato Morifuji Hideki Momose Masahiko Kondow 《Physica E: Low-dimensional Systems and Nanostructures》2006,33(2):381-387
In order to investigate formation process of electronic quantum states in a confined system, we simulate motion of a wavepacket state and show how an eigenstate is formed due to coherence of electronic wave from the viewpoint that an eigenstate arises as a result of self-interference of a moving electron. Numerical results for a Hénon–Heiles potential in which chaotic motion can occur in the classical mechanics indicate that electronic eigenstates can arise even when motion of an electron is non-periodic. The results show that, in the quantum mechanics, periodicity is unnecessary for the formation of eigenstates. 相似文献
107.
Takeda Masuo Wang Junhu Nishimura Tatsuru Suzuki Katsuya Kitazawa Takafumi Takahashi Masashi 《Hyperfine Interactions》2004,156(1-4):359-364
Hyperfine Interactions - We have examined the 155Gd Mössbauer spectra at 12 K for 25 complexes having different coordination numbers and different ratios of coordinating oxygen to nitrogen... 相似文献
108.
Yutaka Wada Yoshio Seike Nobuyuki Tsuboi Katsuya Hasegawa Kiyokazu Kobayashi Makihito Nishioka Keiichi Hori 《Proceedings of the Combustion Institute》2009,32(2):2005-2012
Tetra-ol glycidyl azide polymer (GAP) is one of the best candidates for the solid fuel of gas hybrid rocket system because of self-combustibility, better mechanical property and high heat of formation, and comprehensive understanding of combustion phenomena is indispensable for such an application. Combustion model of GAP, which is one-dimensional three-phase mode combustion model, was developed by Beckstead et al. and they applied it to tri-ol GAP successfully. We have applied this model to tetra-ol GAP as an initial attempt, and numerical simulation showed that maximum temperatures in the gas phase exceeded those of experimental results significantly, and calculated burning rates were much higher than strand burner data, thus, modification of the model taking account of combustion incompleteness was found to be necessary. Combustion residues of GAP were investigated, and those were found to be composed of soot (black color), and high viscosity residue (HVR), and yellow powder which was only observed at high pressures. These residues were analyzed by means of SEM and FTIR, and mass balance was also measured. Modifications of combustion model were made taking the residue analysis results into account as Blow Off Mechanism. Simulated final temperature in the gas phase and burning rate are lowered effectively and coincide well with experimental data adjusting kinetic parameters. 相似文献
109.
Kazuo Sasazawa Yuko Yamada Akiko Fujisawa Toshikazu Saitoh Katsuya Ueno Kazuya Oharu Hideo Sawada 《Colloid and polymer science》2005,283(7):812-816
Self-assembled fluorinated molecular aggregates formed by fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomers, N,N-dimethylacrylamide oligomers, and acrylic acid oligomers in methanol could selectively recognize fluoresceins as guest molecules to form a new class of fluorinated aggregates-fluorescein nanocomposites. These fluorinated fluorescein nanocomposites that are obtained exhibit an extraordinarily enhanced light absorption (max ca. 440 nm) compared to that (maxs 452, 480 nm) of the parent fluorescein in the absence of fluorinated aggregates. 相似文献
110.