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161.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(11):2993-2996
Simple cyclic disulfides under high tension mediate the uptake of giant substrates, that is, liposomes and polymersomes with diameters of up to 400 nm, into HeLa Kyoto cells. To place them at the surface of the vesicles, the strained disulfides were attached to the head‐group of cationic amphiphiles. Bell‐shaped dose response curves revealed self‐activation of the strained amphiphiles by self‐assembly into microdomains at low concentrations and self‐inhibition by micelle formation at high concentrations. Poor colocalization of internalized vesicles with endosomes, lysosomes, and mitochondria indicate substantial release into the cytosol. The increasing activity with disulfide ring tension, inhibition with Ellman's reagent, and inactivity of maleimide and guanidinium controls outline a distinct mode of action that deserves further investigation and is promising for practical applications. 相似文献
162.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(18):5183-5187
A novel and catalyst‐free multicomponent reaction with cyclic tertiary amines, electron‐deficient aryl halides or heteroaromatic halides, and Na2S enabled by facile C−N bond cleavage of the cyclic tertiary amines was developed. This direct and operationally simple method can be applied with a wide range of functional groups and provides an efficient and rapid approach to potentially drug‐like products containing amine, azaarene, thioether, or phenol ether functionalities in good to excellent yields. The utility of this method was demonstrated by the rapid synthesis of the analgesic ruzadolane. 相似文献
163.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(31):9274-9278
The ternary iron‐group thiospinels of metal diindium sulfides (MIn2S4, M=Fe, Co, Ni) with a vertically aligned nanosheet array structure are fabricated through an in situ solvothermal method on F‐doped tin oxide (FTO) substrates, which are employed as one type of platinum (Pt)‐free counter electrodes (CEs) in structure‐dependent dye‐sensitized solar cells (DSSCs). A DSSC assembled with ternary CoIn2S4 CE achieves an photoelectric conversion efficiency (PCE) of 8.83 %, outperforming than that of FeIn2S4 (7.18 %) and NiIn2S4 (8.27 %) CEs under full sunlight illumination (100 mW cm−2, AM 1.5 G), which is also comparable with that of the Pt CE (8.19 %). Putting aside that the interconnected nanosheet array provides fast electron transfer and electrolyte diffusion channels, the highest PCE of CoIn2S4 based DSSC results from its largest specific surface area (144.07 m2 g−1), providing abundant active sites and the largest electron injection efficiency from CE to electrolyte. 相似文献
164.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(42):13283-13286
The construction of all C(sp3) quaternary centers has been successfully achieved under Ni‐catalyzed cross‐electrophile coupling of allylic carbonates with unactivated tertiary alkyl halides. For allylic carbonates bearing C1 or C3 substituents, the reaction affords excellent regioselectivity through the addition of alkyl groups to the unsubstituted allylic carbon terminus. The allylic alkylation method also exhibits excellent functional‐group compatibility, and delivers the products with high E selectivity. 相似文献
165.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(38):11703-11706
The first highly enantioselective iridium‐catalyzed allylic alkylation that provides access to products bearing an allylic all‐carbon quaternary stereogenic center has been developed. The reaction utilizes a masked acyl cyanide (MAC) reagent, which enables the one‐pot preparation of α‐quaternary carboxylic acids, esters, and amides with a high degree of enantioselectivity. The utility of these products is further explored through a series of diverse product transformations. 相似文献
166.
利用再发射技术能够有效测量早期辐射驱动对称性。2011年在神光Ⅱ激光装置上,采用Bi替代靶,通过改变靶丸的支撑方式和优化探测器配置,利用分幅相机获得较高信噪比的Bi球表面再发射图像。利用实验结果获得了入射流不对称性P2分量随时间的变化,对比两种腔长的黑腔,P2分量随时间的变化存在明显差别。两种腔P2分量随时间的变化趋势与采用视角因子模拟的结果基本一致。 相似文献
167.
The rapidity densities at mid-rapidity and the transverse momentum distributions for strange hadrons produced in pp collisions are analyzed using the modified PACIAE model by considering the effect of inelastic (re)scattering processes s→gg and gg→s in parton (re)scattering. The calculated results of the transverse momentum spectra of the strangeness fitting with data measured by STAR and ALICE Collaborations can be improved, especially at large transverse momentum levels. This demonstrates that the effect of inelastic (re)scattering processes of s→gg and gg→s is not negligible at RHIC and LHC energy levels. 相似文献
168.
For the more general parabolic Monge-Ampère equations defined by the
operator $F(D^2u + σ(x))$, the existence and uniqueness of the admissible solution to
the third initial-boundary value problem for the equation are established. A new
structure condition which is used to get a priori estimate is established. 相似文献
169.
170.
Sivan Louzoun‐Zada Qais Z. Jaber Micha Fridman 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(44):15730-15740
The ratio between the dose of drug required for optimal efficacy and the dose that causes toxicity is referred to as the therapeutic window. This ratio can be increased by directing the drug to the diseased tissue or pathogenic cell. For drugs targeting fungi and malignant cells, the therapeutic window can be further improved by increasing the resolution of drug delivery to the specific organelle that harbors the drug's target. Organelle targeting is challenging and is, therefore, an under‐exploited strategy. Here we provide an overview of recent advances in control of the subcellular distribution of small molecules with the focus on chemical modifications. Highlighted are recent examples of active and passive organelle‐specific targeting by incorporation of organelle‐directing molecular determinants or by chemical modifications of the pharmacophore. The outstanding potential that lies in the development of organelle‐specific drugs is becoming increasingly apparent. 相似文献