The luminescence dynamics of a polypyridyl ruthenium II [Ru(phen)2(ip)]2+ and 5,10,15,20- tetraphenylporphyrin (H2TPP) dyad have been measured by using time-resolved fluorescence spectroscopy. The transient luminescent spectra of the dyad show an ultrafast energy transfer within 300 ps after pho- toexcitation of the [Ru(phen)2(ip)]2+ at 453 am. However, no energy transfer has been observed as the excitation wavelength is 400 nm, corresponding to the absorption peak of H2TPP. The origin of the energy transfer from [Ru(phen)2(ip)]2+ to H2TPP has been analyzed according to the FSrster energy-transfer theory.
Three-dimensional quantitative structure-activity relationship (3D-QSAR) and docking studies of a series of novel dioxopyrrolinyl-amino-pyrimidine derivatives, which are potential dual inhibitors mediating a transcriptional activation towards protein-1 (AP-1) and nuclear factor kappa B (NF-κB), have been carried out. The QS, AR models established by comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) show a good predictive ability with cross-validated coefficients q2 of 0.644 and 0.636, respectively. The docking result shows that there are quite lower average values of the flexible and rigid energy scores on the selected binding sites, meanwhile, it further shows that the binding sites just fall on the joint regions between AP-1 (and NF-κB) and DNA. The reason that these analogues have inhibition function towards AP-I and NF-κB is that their existence on these joint regions can effectively prevent free AP-I and NF-κB from binding to DNA. These results can offer a valuable theoretical reference to the pharmaceutical molecular design as well as the action mechanism analysis.
QIAN Li LIAO Si-yan MIAO Ti-fang SHEN Yong ZHENG Kang-cheng