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441.
Kasmi-Mir S Djafri A Paquin L Hamelin J Rahmouni M 《Molecules (Basel, Switzerland)》2006,11(8):597-602
A rapid and easy solvent free one-pot synthesis of 5-arylidene-2-imino-4-thiazolidinones by condensation of the thioureas with chloroacetic acid and an aldehyde under microwave-irradiation is described. 相似文献
442.
We report on the rapid production, characterization, and spectral properties of highly uniform, ultra narrow semiconductor (ZnS, ZnSe, CdS, CdSe) nanorods and nanowires by microwave irradiation. Quantum-confinement effects are manifested in the light absorption and the PL of the rods and wires. The uniformity of the rods and of the wires is demonstrated in their spontaneous assembly into highly ordered 2D supercrystals. We also observed the stepwise growth of the rods originating from nearly spherical nuclei. 相似文献
443.
444.
Samy A. El-Daly Khalid A. Alamry Abdullah M. Asiri Mahmoud A. Hussein 《Journal of luminescence》2012,132(10):2747-2752
The photophysical properties such as electronic absorption, molar absorptivity, emission spectra, fluorescence quantum yield and fluorescence lifetime of N,N′-bis(4-pyridyl)-3,4:9,10-perylene bis(dicarboximide) (BPPD) have been measured in different solvents. Both electronic absorption and fluorescence spectra are not sensitive to medium polarity, while the fluorescence quantum yield (?f) is solvent dependent. The ground state geometry has been computed by using density functional theory (DFT), the transition from HOMO to LUMO from perylene core with maximum absorption at 512 nm and HOMO–LUMO energy difference equal 2.53 eV. BPPD dye undergoes molecular aggregation to dimmer or higher aggregates in dimethyl sulfoxide (DMSO). Crystalline solids of BPPD gives excimer-like emission at 676 nm. The fluorescence quenching of BPPD is also studied using hydrated ferric oxide nanoparticle (FeOOH), and the Stern–Volmer rate constants (Ksv) were calculated as 8×106 and 9.2×106 M?1 in ethanol and ethylene glycol, respectively. 相似文献
445.
Cécile Bousch Brandon Vreulz Kartikey Kansal Ali El-Husseini Dr. Samy Cecioni 《Angewandte Chemie (International ed. in English)》2023,62(49):e202314248
Glycan recognition by glycan-binding proteins is central to the biology of all living organisms. The efficient capture and characterization of relatively weak non-covalent interactions remains an important challenge in various fields of research. Photoaffinity labeling strategies can create covalent bonds between interacting partners, and photoactive scaffolds such as benzophenone, diazirines and aryl azides have proved widely useful. Since their first introduction, relatively few improvements have been advanced and products of photoaffinity labeling remain difficult to detect. We report a fluorinated azido-coumarin scaffold which enables photolabeling under fast and mild activation, and which can leave a fluorescent tag on crosslinked species. Coupling this scaffold to an α-fucoside, we demonstrate fluorogenic photolabeling of glycan-protein interactions over a wide range of affinities. We expect this strategy to be broadly applicable to other chromophores and we envision that such “fluoro-crosslinkers” could become important tools for the traceable capture of non-covalent binding events. 相似文献
446.
3,5-Diethoxycarbonyl 1,2,4-diazaphospholes and arsoles undergo N-alkylation by reaction with alkyl vinyl ether, sulfur ylides, and diazocompounds, owing to the acidity of the NH group. © 1995 John Wiley & Sons, Inc. 相似文献