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[reaction: see text] Novel rod-shaped polycyano-oligo(phenyleneethynylene)s were synthesized by Pd cross-coupling reaction. Polycyano groups were found to greatly improve the emission efficiency (Phi(f)) of OPEs. By the end donor modification, we achieved the creation of very intense blue light-emitting fluorophore with the SMe group (Phi(f) = 0.972, log epsilon 4.89, lambda(em) 455 nm) and very intense yellow light-emitting fluorophore with the NMe(2) group (Phi(f) = 0.999, log epsilon 4.75, lambda(em) 555 nm). Contrasting Phi(f) solvent dependency of 6 and 7 and a linear relationship between Phi(f) and sigma(p)-X over the whole region of sigma(p)-X were also found. 相似文献
113.
Akine S Taniguchi T Matsumoto T Nabeshima T 《Chemical communications (Cambridge, England)》2006,(47):4961-4963
Complexation of linear hexaoxime ligand H6L with Zn2+ and Mn+ (= La3+, Ba2+) afforded a tetranuclear single metallohelicate [LZn3M]n+, whose inversion rate can be modulated by the central metal Mn+. 相似文献
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Kobayashi T Nakanishi H Nishizawa NK 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(9):900-913
Higher plants utilize various mechanisms to maintain iron homeostasis. To acquire sparingly soluble iron from the rhizosphere, graminaceous plants synthesize natural iron (III) chelators known as mugineic acid family phytosiderophores (MAs). Recent research has uncovered various genes involved in iron uptake and translocation, as well as factors regulating the expression of these genes, especially in rice. Manipulation of these molecular components is used to produce transgenic crops with enhanced tolerance to iron deficiency, or with a high seed iron content. Since iron homeostasis is closely linked to that of other mineral elements, an understanding of this phenomenon will serve as the basis for the production of crops with low concentrations of toxic metals and transgenic plants for phytoremediation. 相似文献
118.
Matsuya Y Kawaguchi T Ishihara K Ahmed K Zhao QL Kondo T Nemoto H 《Organic letters》2006,8(20):4609-4612
Hybrid compounds of macrosphelides and epothilones, both of which are natural macrolides having a 16-membered skeleton, were designed and synthesized using a ring-closing metathesis (RCM) strategy. Some of these hybrids were found to exhibit notable apoptosis-inducing activity against human lymphoma cells with higher potency than parent natural macrosphelides, and to be a promising lead compound for development of a new antitumor agent. 相似文献
119.
H. Matsubara M. Takaki T. Uesaka S. Shimoura N. Aoi M. Dozono T. Fujii K. Hatanaka T. Hashimoto T. Kawabata S. Kawase K. Kisamori Y. Kikuch Y. Kubota C. S. Lee H. C. Lee Y. Maeda S. Michimasa K. Miki H. Miya S. Noji S. Ota S. Sakaguchi Y. Sasamoto T. Suzuki L. T. Tang K. Takahisa H. Tokieda A. Tamii K. Yako Y. Yasuda N. Yokota R. Yokoyama J. Zenihiro 《Few-Body Systems》2013,54(7-10):1433-1436
Spectroscopy for neutron-rich nuclei 9He and 12Be has been performed by means of heavy-ion double charge exchange (HIDCX) (18O, 18Ne) reaction on stable target nuclei 9Be and 12C, respectively. Several clear peaks in 12Be at low excitation energy region even above neutron separation energy have been observed in one-shot measurement, whereas no prominent signals of 9He have been observed owing to the small cross section. It is shown that the HIDCX reaction is a new powerful spectroscopic tool for study of unstable neutron-rich nuclei. 相似文献
120.
Shotaro Hayashi Minami Sakamoto Fumitaka Ishiwari Takanori Fukushima Shin-ichi Yamamoto Toshio Koizumi 《Tetrahedron》2019,75(8):1079-1084
Here we report the facile derivatization of a cyano-substituted stilbene into higher π-extended analogues. The cyano-substituted stilbene, which serves as a synthetic scaffold, has a bromo group and a formyl group on its 4- and 4′-position of the phenylene rings and thus readily undergoes selective transformation into other functional groups using various simple organic reactions. The resultant π-conjugated molecules that contain a cyano-substituted stilbene skeleton exhibit fluorescence in solution and in the solid state. 相似文献