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In the present work, a theoretical study of five bipyrazolic-type organic compounds, 4-{bis[(3,5-dimethyl-1H-pyrazolyl-1-yl)methyl]-amino}phenol (1), N1,N1-bis[(3,5-dimethyl-1H-pyrazol-1-yl)methyl}]-N4,N4-dimethyl-1,4-benzenediamine (2), N,N-bis[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]aniline (3), 4-[bis(3,5-dimethyl pyrazol-1-yl-methyl)-amino]butan-1-ol (4) and ethyl4-[bis(3,5-dimethyl-1H-pyrazol-1-yl-methyl) aminobenzoate] (5), has been performed using density functional theory (DFT) at the B3LYP/6-31G(d) level in order to elucidate the different inhibition efficiencies and reactive sites of these compounds as corrosion inhibitors. The efficiencies of corrosion inhibitors and the global chemical reactivity relate to some parameters, such as EHOMO, ELUMO, gap energy (DeltaE) and other parameters, including electronegativity (chi), global hardness (eta) and the fraction of electrons transferred from the inhibitor molecule to the metallic atom (DeltaN). The calculated results are in agreement with the experimental data on the whole. In addition, the local reactivity has been analyzed through the Fukui function and condensed softness indices.

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Design of single‐site catalysts with catalytic sites at atomic‐scale and high atom utilization, provides new opportunities to gain superior catalytic performance for targeted reactions. In this contribution, we report a one‐pot green approach for in situ implanting of single tungsten sites (up to 12.7 wt.%) onto the nodes of defective UiO‐66(Zr) structure via forming Zr‐O‐W bonds under solvent‐free condition. The catalysts displayed extraordinary activity for the oxidative removal of sulfur compounds (1000 ppm S) at room temperature within 30 min. The turnover frequency (TOF) value can reach 44.0 h−1 at 30 °C, which is 109.0, 12.3 and 1.2 times higher than that of pristine UiO‐66(Zr), WO3, and WCl6 (homogeneous catalyst). Theoretical and experimental studies show that the anchored W sites can react with oxidant readily and generate WVI‐peroxo intermediates that determine the reaction activity. Our work not only manifests the application of SSCs in the field of desulfurization of fuel oil but also opens a new solvent‐free avenue for fabricating MOFs based SSCs.

Aptamers are widely used in numerous biochemical, bioanalytical, and biological studies. Most aptamers are developed through an in vitro selection process called SELEX against either purified targets or living cells expressing targets of interest. We report here an in vivo SELEX in mice using a PEGylated RNA library for the identification of a 2′-F RNA aptamer (RA16) that specifically binds to NCI-H460 non-small-cell lung cancer cells with an affinity (KD) of 9 ± 2 nM. Interestingly, RA16 potently inhibited cancer cell proliferation in a dose-dependent manner with an IC50 of 116.7 nM. When tested in vivo in xenografted mice, RA16 showed gradual migration toward tumor and accumulation at tumor site over time. An in vivo anti-cancer study showed that the average inhibition rate for mouse tumors in the RA16-treated group was 54.26% ± 5.87% on day 16 versus the control group. The aptamer RA16 adducted with epirubicin (RA16-epirubicin) showed significantly higher toxicity against targeted NCI-H460 cells and low toxicity against non-targeted tumor cells. Furthermore, RA16-epirubicin adduct exhibited in vivo anti-cancer efficacy, with an inhibition rate of 64.38% ± 7.92% when administrated in H460 xenograft mouse model. In summary, a specific bi-functional RNA aptamer RA16 was selected targeting and inhibiting toward NCI-H460 in vitro and in vivo.