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21.
The photoinduced persistent intramolecular charge‐transfer state of 4‐carbazolyl‐3‐(trifluoromethyl)benzoic acid was confirmed. It showed a higher catalytic activity in terms of yield and selectivity in the photochemical reduction of alkyl halides compared to the parent carbazole. Even unactivated primary alkyl bromides could be reduced by this photocatalyst. The high catalytic activity is rationalized by considering the slower backward single‐electron transfer owing to the spatial separation of the donor and acceptor subunits.  相似文献   
22.
Oleamide is an interesting compound, which shows various pharmacological activities including the inhibitory effect of gap junction formation. Recently, the studies of the gap junction have been some of the hot topics in biology and its inhibitors have become more useful tools [Cravatt, B. F.; Garcia, O. P.; Siuzdak, G.; Gilula, N. B.; Henriksen, S. J.; Boger, D. L.; Lerner, R. A. Science1995, 268, 1506-1509; Cravatt, B. F.; Lerner, R. A.; Boger, D. L. J. Am. Chem. Soc.1996, 118, 580-590; Guan, X; Cravatt, B. F.; Ehring, G. R.; Hall, J. E.; Boger, D. L.; Lerner, R. A.; Gilula, N. B. J. Cell Biol.1997, 139, 1785-1792; Boger, D. L.; Patterson, J. E.; Guan, X.; Cravatt, B. F.; Lerner, R. A.; Gilula, N. B. Proc. Natl. Acad. Sci. U.S.A.1998, 95, 4810-4815; Ito, A.; Morita, N.; Miura, D.; Koma, Y.; Kataoka, T. R.; Yamasaki, H.; Kitamura, Y.; Kita, Y.; Nojima, H. Carcinogenesis2004, 25, 2015-2022]. However, many reports suggest that the functionalizations of oleamide to retain its biological activity were difficult [Boger, D. L.; Patterson, J. E.; Guan, X.; Cravatt, B. F.; Lerner, R. A.; Gilula, N. B. Proc. Natl. Acad. Sci. U.S.A.1998, 95, 4810-4815; Ito, A.; Morita, N.; Miura, D.; Koma, Y.; Kataoka, T. R.; Yamasaki, H.; Kitamura, Y.; Kita, Y.; Nojima, H. Carcinogenesis2004, 25, 2015-2022]. The synthesis of the functionalized oleamide derivatives, whose biological activity is not blocked, has become attractive in both the biological and chemical fields.Herein, by linking the fluorophore to the oleamide by alkyl chains, we synthesized the fluorescently tagged oleamide whose biological feature is similar to that of oleamide. Moreover, we also synthesized other bioactive derivatives tagged by other groups such as the sugars and biotin via alkyl chain linkers.  相似文献   
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24.
Recently, Masanobu Kaneko introduced a conjecture on an extension of the derivation relation for multiple zeta values. The goal of the present paper is to present a proof of the conjecture by reducing it to a class of relations for multiple zeta values studied by Kawashima. In addition, some algebraic aspects of the quasi-derivation operator on Qx,y〉, which was defined by modeling a Hopf algebra developed by Connes and Moscovici, will be presented.  相似文献   
25.
Summary: Protein chips are important tools for high-throughput analysis of biological events. We have developed a novel method to prepare a protein-based hydrogel, that is, a “Three-Dimensional Nano-structured Protein Hydrogel” (3-D NPH), which is composed of protein and polymer nano-particles. The 3-D NPH could be easily prepared by dispensing a protein and polymer mixture on a substrate. Surprisingly, gold particles conjugated with protein A diffused into the 3-D NPH which was made of mouse IgG through the pores. We have shown that the protein chips made with our 3-D NPH method has tremendously improved sensitivity in detecting protein-protein interactions compared with that of direct protein immobilization methods.  相似文献   
26.
TextThe Bowman–Bradley theorem asserts that the multiple zeta values at the sequences obtained by inserting a fixed number of twos between 3,1,,3,1 add up to a rational multiple of a power of π. We establish its counterpart for multiple zeta-star values by showing an identity in a non-commutative polynomial algebra introduced by Hoffman.VideoFor a video summary of this paper, please click here or visit http://www.youtube.com/watch?v=LpqA2OJ6vP8.  相似文献   
27.
In this paper, we systematically study several classes of maximal singular integrals and maximal functions with rough kernels in F_β(S~(n-1)), a topic that relates to the Grafakos-Stefanov class. The boundedness and continuity of these operators on Triebel-Lizorkin spaces and Besov spaces are discussed.  相似文献   
28.
Multilinear Singular and Fractional Integrals   总被引:2,自引:0,他引:2  
In this paper, we treat a class of non-standard commutators with higher order remainders in the Lipschitz spaces and give (L^v, L^q), (H^p, L^q) boundedness and the boundedness in the Triebel- Lizorkin spaces. Our results give simplified proofs of the recent works by Chen, and extend his result.  相似文献   
29.
Littlewood-paley operators on the generalized Lipschitz spaces   总被引:3,自引:0,他引:3  
Littlewood-Paley operators defined on a new kind of generalized Lipschitz spaces 0 ,p are studied. It is proved that the image of a function under the action of these operators is either equal to infinity almost everywhere or is in 0 ,p , where –n<<1 and 1<p<.  相似文献   
30.
We introduce an algebraic formulation of the cyclic sum formulas for multiple zeta values and for multiple zeta-star values. We also present an algebraic proof of cyclic sum formulas for multiple zeta values and for multiple zeta-star values by reducing them to Kawashima's relation.  相似文献   
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