We designed a series of 2-methylpyrimidine derivatives as new BCR-ABL inhibitors using scaffold-hopping strategy.These synthetic compounds exhibited significant inhibition against a broad spectrum of Bcr-Abl mutants including the gatekeeper T315I mutant.Compound 7u showed very potent kinase inhibitory activities against Bcr-Abl WT,Bcr-Abl E255K,Bcr-Abl Q252H,Bcr-Abl G250E and Bcr-Abl T315I,with IC50 values of 0.13 nM,0.17 nM,0.24 nM,0.19 nM and 0.65μM,respectively.This compound also displayed anti-proliferation activity against K562 cell line with an IC50 value of 1.1 nM,thus representing a new lead for further optimization. 相似文献
We demonstrate here a novel method for the design of liquid crystals (LCs) via the cyclization of mesogens by flexible chains. For two azobenzene-4,4′-dicarboxylate derivatives, the cyclic dimer, cyclic bis(tetraethylene glycol azobenzene-4,4′-dicarboxylate) (CBTAD), shows LC properties with smectic A phase, while its linear counterpart, bis(2-(2′-hydroxyethyloxy)ethyl azobenzene-4,4′-dicarboxylate (BHAD), has no LC phase. The difference is ascribed to the shackling effect from the cyclic topology, which leads to the much smaller entropy change during phase transitions and increases the isotropic temperature greatly for cyclics. In addition, the trans-to-cis isomerization of azobenzene groups under UV-light is also limited in CBTAD. With the reversible isomerization of azobenzene groups, CBTAD showed interesting isothermal phase transition behaviors, where the LC phase disappeared upon photoirradiation of 365 nm UV-light, and recovered when the UV-light was off. Combined with the smectic LC nature, a novel UV-light tuned visible light regulator was designed, by simply placing CBTAD in two glass plates. The scattered phase of smectic LC was utilized as the “OFF” state for light passage, while the UV-light induced isotropic phase was utilized as the “ON” state. The shackling effect outlined here should be applicable for the design of cyclic LC oligomers/polymers with special properties.
Journal of Thermal Analysis and Calorimetry - As high heat dissipation has increasingly become the primary factor restricting the capability of electronic elements, and the high temperature of the... 相似文献
This paper describes a novel approach to detect Cd(II) using the combination of the differential pulse anodic stripping voltammetry and magnetic nanoparticle based dispersive solid phase microextraction as an efficient, green and accurate method. Currents of Cd(II) increased linearly in the range from 75 to 2000 ng L−1 Cd(II) with a detection limit of 21.6 ng L−1. The RSD values of 2.6 and 6.0 % for 1.00 and 0.10 μg L−1 respectively showed that proposed method has an acceptable repeatability. Recovery values between 92.3 and 98.6 % showed that this approach can be successfully used for determination of Cd(II) in water samples. 相似文献
Continuum generation from normally dispersive ultrahigh-numerical-aperture fibers deteriorates in relatively short times, limiting its application as a practical optical source for high-resolution optical coherence tomography. We find that reversible light-induced structural modification of fiber optic materials, rather than permanent optical damage, is responsible for this deterioration. By examining how the optical properties of corresponding light-induced waveguides depend on pumping wavelength, we isolate a waveguide that is beneficial for stable continuum generation. The performance deterioration due to the formation of other waveguides can be reversed by overwriting them with this particular waveguide. 相似文献
Journal of Structural Chemistry - We report a comprehensive study of the effect of the chemical structure of boron carbonitride films on the variability of their functional characteristics. The... 相似文献
Here,the selective adsorption behaviors of guest molecule COR in two hexamer host grids were investigated by means of scanning tunnelling microscope(STM).The assembled structures of small functional organic molecules TTBTA and TATBA were thermodynamically stable.Interestingly,the introduction of the guest molecule COR destroyed the original hexamer structure of TTBTA and combined with it to form a new triangular host-guest system.Different from TTBTA,the introduction of the guest molecule COR did not affect the six-membered ring structure of TATBA.Furthermore,the co-assembly structure of TTBTA/TATBA/COR was established and the guest molecule COR showed preferential adsorption to the TATBA host grid.Density functional theory(DFT) calculations had been performed to disclose the mechanism of the involved assemblies. 相似文献
We report three‐dimensional (3D) nanoporous graphene with preserved 2D electronic properties, tunable pore sizes, and high electron mobility for electronic applications. The complex 3D network comprised of interconnected graphene retains a 2D coherent electron system of massless Dirac fermions. The transport properties of the nanoporous graphene show a semiconducting behavior and strong pore‐size dependence, together with unique angular independence. The free‐standing, large‐scale nanoporous graphene with 2D electronic properties and high electron mobility holds great promise for practical applications in 3D electronic devices. 相似文献
Recent experiments have shown the coexistence of both large unoxidized and oxidized regions on graphene oxide (GO), but the underlying mechanism for the formation of the GO atomic structure remains unknown. Now, using density functional calculations, 52 oxidation pathways for local pyrene structures on GO were identified, and a kinetic profile for graphene oxidation with a high correlation between oxidation loci was proposed, which is different from the conventional view, which entails a random distribution of oxidation loci. The high correlation is an essential nature of graphene oxidation processes and can be attributed to three crucial effects: 1) breaking of delocalized π bonds, 2) steric hindrance, and 3) hydrogen‐bond formation. This high correlation leads to the coexistence of both large unoxidized and oxidized regions on GO. Interestingly, even in oxidized regions on GO, some small areas of sp2‐hybridized domains, similar to “islands”, can persist because of steric effects. 相似文献