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991.
A novel bichromophoric conjugate integrating a NO photodonor and a DNA intercalator in its molecular skeleton, allows the light-controlled NO delivery nearby DNA and amplifies NO release via effective photoinduced energy transfer mechanism. 相似文献
992.
Magazù S Maisano G Migliardo F Benedetto A 《The journal of physical chemistry. B》2008,112(30):8936-8942
In the present work an operational recipe for the mean square displacement (MSD) determination, highlighting the connection between the self-distribution function and average statistical values, is presented. The determination of the MSD and of its contributions associated with different mechanisms, together with their thermal behavior, is performed by evaluating the self-distribution function derived by elastic incoherent neutron scattering (EINS). The approach is tested on EINS data collected by the backscattering spectrometer IN13 (ILL, Grenoble, France) on two model systems such as dry myoglobin in trehalose and poly(ethylene glycol) with mean molecular weight M(w) = 400 (PEG 400). 相似文献
993.
Zinellu A Sotgia S Usai MF Zinellu E Lepedda AJ Deiana L Formato M Carru C 《Analytical and bioanalytical chemistry》2008,391(8):2865-2868
We describe a new ultra-rapid capillary electrophoresis method with UV detection for analysis of the disaccharides obtained
after enzymatic depolymerization of plasma chondroitin sulfates. The free reducing groups of the released carbohydrate molecules
are derivatized with 2-aminoacridone by reductive amination in the presence of cyanoborohydride. The fluorotagged products
can be separated by short-end injection capillary electrophoresis in a capillary with an effective length of 10.2 cm. The
migration times of Δdi-0S and Δdi-4S were 0.95 and 1.81 min, respectively. We compared the proposed method with UV detection
to a reference CE-LIF assay by measuring plasma chondroitin sulfate in 94 subjects. The described assay for total plasma CS
measurement may, owing to the high throughput and the fast analytical times, be a good tool for routine studies both in research
and in clinical applications. 相似文献
994.
We have synthetized medium-sized cyclophanes and macrocycles containing phosphonic groups, directly linked to the aromatic rings of the phanes or as pendant arms,for use as specific receptors for the selective complexation of neutral guests or for complexing lanthanides, as luminescent sensors and for diagnostic bioassays in medicine.Furthermore, because it would be of great interest for biochemistry as well as for pharmacological studies to dispose of preorganized rigid chiral hosts for biorelevant molecules we designed inter alia, some new chiral macrocycles capable of a triple binding mode and we used them for constructing macrocycles that could also be of interest for chiral recognition and chiral separations. Thus, in this paper we shall review the salient aspects of some macrocycles synthetized in our laboratory, all possessing the phosphonate moiety and a spirobisindanol scaffold and able to act as complexing agents for cations and organic substrates. In particular, we shall describe their NMR characterization, their stereochemistry in solution and in the solid state, and their use as chiral receptors for biorelevant molecules. Chiral HPLC resolution of some of them is also reported. 相似文献
995.
996.
Poletto L Villoresi P Benedetti E Ferrari F Stagira S Sansone G Nisoli M 《Optics letters》2007,32(19):2897-2899
Extreme-ultraviolet pulses, produced by high-order harmonic generation, have been spectrally selected by a time-delay-compensated grating monochromator. Temporal characterization of the harmonic pulses has been obtained using cross-correlation method: pulses as short as 8 fs, with high photon flux, have been measured at the output of the monochromator. 相似文献
997.
998.
Güell M Martín N Altable M Filippone S Martín-Domenech A Solà M 《The journal of physical chemistry. A》2007,111(24):5253-5258
Substitution of a H atom by an alkyl group on the terminal carbon of the alkyne moiety of 1,6-fullerenynes has a strong impact on the products of the reaction undergone by this species after thermal treatment. While the reaction of 1,6-fullerenynes bearing an unsubstituted alkyne moiety results in the cycloaddition of the alkyne group to the fullerene double bond leading to cyclobutene-fused derivatives, the presence of an alkyl substituent leads to the formation of allenes. In the present work, we have performed an exhaustive theoretical analysis of all possible reaction mechanisms leading to cyclobutene-fused derivatives and allenes to offer an explanation of the reactivity differences observed. The results obtained show that formation of cyclobutene-fused derivatives occurs through a stepwise diradical reaction mechanism, while allene formation proceeds through a concerted way involving an uncommon intramolecular ene process. For the 1,6-fullerenynes bearing a substituted alkyne, the ene reaction path leading to allenes has an energy barrier somewhat lower than the stepwise diradical mechanism for the cyclobutene-fused derivative formation, thus explaining the outcome of the reaction. 相似文献
999.
1000.
Giuseppe C. Pappalardo Salvatore Gruttadauria 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):1-4
Abstract Barriers to rotation about C[sbnd]C and C[sbnd]N bonds in 2-, 3- and 4-thioamidopyridine have been calculated by the CNDO/2 method. Comparisons between computed and experimental data are used to assess reliability of the calculations. 相似文献