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571.
The equilibrium structures and relative stabilities of BN-doped fullerenes C70−2x(BN)x (x=1–3) have been studied at the AM1 and MNDO level. The most stable isomers of C70−2x(BN)x have been found out and their electronic properties have been predicted. The calculation results show that the BN substituted fullerenes C70−2x(BN)x have considerable stabilities, though they are less stable than their all carbon analog. For C68BN, the isomers whose BN is located in the most chemically active bonds of C70 (namely B and A) are among the most stable species, of which B is predicted to be the ground state. The stabilities of C68BN decrease and the dipole moments increase with increasing the distance between the heteroatoms. For C66(BN)2, the lowest energy species is the isomer in which the B–N–B–N bond is formed; For C64(BN)3, the most stable species should have three BN units located in the same hexagon to form B–N–B–N–B–N ring. The ionization potentials and the affinity energies of the most stable species of BN-doped C70 are almost the same as those of C70 because of the isoelectronic relationship. The ionization potentials and affinity energies depend on the relative position of the heteroatoms in C68BN, the chemical reactivities of the isomers whose heteroatoms are well separated should differ significantly from their all carbon analog. 相似文献
572.
Rico Schwarz Elisabeth R. D. Seiler Sina Sender Anahit Pews-Davtyan Hugo Murua Escobar Dietmar Zechner Matthias Beller Christian Junghanß Burkhard Hinz 《Molecules (Basel, Switzerland)》2022,27(3)
The treatment of cancer is one of the most important pharmacotherapeutic challenges. To this end, chemotherapy has for some time been complemented by targeted therapies against specific structures. PDA-66, a structural analogue of the inhibitor of serine–threonine kinase glycogen synthase kinase 3β SB216763, has shown preclinical antitumour effects in various cell lines, with the key pathways of its anticancer activity being cell cycle modulation, DNA replication and p53 signalling. For the monitoring of anticancer drug treatment in the context of therapeutic drug monitoring, the determination of plasma concentrations is essential, for which an LC-MS/MS method is particularly suitable. In the present study, a sensitive LC-MS/MS method for the quantification of the potential anticancer drug PDA-66 in human plasma with a lower limit of quantification of 2.5 nM is presented. The method was successfully validated and tested for the determination of PDA-66 in mouse plasma and sera. 相似文献
573.
In this study, a sonochemical route for the preparation of a new Hf-MIL-140A metal–organic framework from a mixture of UiO-66/MIL-140A is presented. The sonochemical synthesis route not only allows the phase-pure MIL-140A structure to be obtained but also induces structural defects in the MIL-140A structure. The synergic effect between the sonochemical irradiation and the presence of a highly acidic environment results in the generation of slit-like defects in the crystal structure, which increases specific surface area and pore volume. The BET-specific surface area in the case of sonochemically derived Zr-MIL-140A reaches 653.3 m2/g, which is 1.5 times higher than that obtained during conventional synthesis. The developed Hf-MIL-140A structure is isostructural to Zr-MIL-140A, which was confirmed by synchrotron X-ray powder diffraction (SR-XRD) and by continuous rotation electron diffraction (cRED) analysis. The obtained MOF materials have high thermal and chemical stability, which makes them promising candidates for applications such as gas adsorption, radioactive waste removal, catalysis, and drug delivery. 相似文献